P\ Contract No. W-7405-eng-26 Reactor Division MSRE DESIGN AND OPERATIONS REPORT PART I DESCRIPTION OF REACTOR DESIGN R. C. Robertson JANUARY 1965 OAK RIDGE NATTONAL LABORATORY - Osk Ridge, Tennessee ' operated by UNION CARBIDE CORPORATION for the U.S. ATOMIC ENERGY COMMISSION ORNL-TM-728 _fl—'w o - e S TATIT P —— > el Y s'y B Unclassified gl Fhoto 71114 Reactor Vessel in Transport Jig Prior to Installation. , iv e -~ - oM o« \O o O w ¢ O 8B = .0 D Ry [ i i W | ! | | i -\ M. i | | ( - PREFACE The report on the Molten-Salt Reactor Experiment (MSRE) has been arranged into twelve major parts as shown in the General Index. Each of these covers a particular phase of the project, such as the design, safety analysis, operating procedures, etc. An attempt has thus been made to avoid much of the duplication of material that would result if separate and independent reports were prepare& on each of these major aspects. Detailed references to supporting documents, working drawings, and other information sources have been made throughout the report to make 1t of meximum value to ORNL personnel. Each of the major divi- sions of the report contains the bibliographical and other appendix information necessary for that part. The final volumes of the report, Part XII, contain the rather ex- tensive listings of working drawings, specifications, schedules, tab- bulations, etc. These have been given a more limited distribution. Most of the reference materigl is available through the Division of Technical Information Extension, Atomic Energy Commission, P. O. Box 62, Oak Ridge, Tennessee. For material not available through this source, such an inter-Iaboratory correspondence, etc., special arrange- ments can be made for those having & particular interest. None of the information contained in this report is of a classi- fied nature. - ?"l A C A" vii ACKNOWLEDGMENT The list of biographical references provides an indication of ORNL Personnel contributing most valuably to the MSRE literature, and thus to this report. Either directly, or indirectly, all of the forty to fifty engineers and scientists in the Reactor Division assigned to the MSRE project helped to prepare this material. Personnel in the Chemistry, Metallurgy, Physics, Engineering and Maintenance, and Instrumentation and Controls Divisions of the Iaboratory also made extensive contributions. In this broad-based team effort it is impossible to single out individuals more deserving to be mentioned here than others. (¥ re X, i C T ix GENERAL INDEX This report is one of a series that describes the design and opera- tion of the Molten-Salt Reactor Experiment. All the reports are listed below. ORNL-TM-728~ ORNL-TM-T729 ORNL-TM-T30% ORNL-TM-T31 ORNL-TM-T732% ORNL-TM-733 ORNL-TM-Q0T¥* ORNL-TM-908%%* ORNL-TM-909%* ORNL-TM-910%* *Tssued. MSRE Design and Operations Report, Part I, Description of Reactor Design by R. C. Robertson MSRE Design and Operations Report, Part 11, Nuclear and Process Instrumentation, by J. R. Tallackson ' MSRE Design and Operations Report, Part III, Nuclear Analysis, by P. N. Haubenreich and J. R. Engel, B. E. Prince, and H. C. Claiborne MSRE Design and Operations Report, Part IV, Chemistry and Materials, by F. F. Blankenship and A. Taboada MSRE Design and Operations Report, Part V, Reactor Safety Analysis Report, by S. E. Beall, P. N. Haubenreich, R. B. Lindauer, and J. R. Tallackson MSRE Design and Operations Report, Part VI, Operating Limits, by S. E. Beall and R. H. Guymon MSRE Design and Operations Report, Part VII, Fuel Handling and Processing Plant, by R. B. Lindasuer MSRE Design and Operations Report, Part VIII, Operating Procedures, by R. H. Guymon MSRE Design and Operations Report, Part IX, Safety Procedures and Emergency Plans, by R. H. Guymon MSRE Design and Operations Report, Part X, Maintenance Equipment and Procedures, by E. C. Hise and R. Blumberg *¥¥These reports will be the last in the series to be published ORNL-TM-911%* ¥ MSRE Design and Operations Report, Part XI, Test Program, by R. H. Guymon and P. N. Haubenreich MSRE Design and Operations Report, Part XII, Lists: Drawings, Specifications, Line Schedules, Instrument Tabulations (Vol. 1 and 2) vy . i xi CONTENTS Page PREFACE . ticvveevrenncsnnnss et etaerraeseanns sesssaneesos ceee v Acmmm ........ l...... ................... * & & 9 b 9 ® & o B 9 0 e Vii GENERAL INDEX .voieecnrecnoceeconansananns Cecercteasranase cesreane ik LISTOFFIGIJRES S v e e se s be st s s tesebtee e e s a0 e TR EE R E R TS mll LIST OF TABIES .ivvvecervrveneesnacsoceass crvesas srccesrnsssnns xxix 1. INTRODUCTION .....c.... Cetteseiaisacsitinetarraaeas ceesenns 3 2. GENERAL DESCRIPTION ....c.evnee. Ceereecaaas et eeneraancanne 7 2'1 Tm o & & & ® 28 & F 00 9 0 8 R P S BT 48 TR R 0SB .0.““........'...... 7 2.2 " Loca‘tion * ¢ 8 & 5 &0 09 " O e 0Pt 2 E O S E P EES R * 8 o & 5 5 & 0 08 & e '7 2.3 TFuel and Coolant Salts .......... sesesaesscsascsace s 7 2.4 Equipment and Processes ........ ceecens trecene cesecns 9 2.4.1 ReaCtor ....vveieiennnincnns Ceeceteacanecas .- 9 2'04-2 Fuel Pmp te 0 s 00 ® e e s s e e race ¢t s o9 s e 6 & 0 0 st e s 12 2.4.3 Heat EXChANEEY .v.veeeeveesscosanacans e 14 2.4,4 Coolant Pump ...... Ceeeresseseaana ceccans ceos 14 2.4.5 Radiator ....cvieeee- Cersenes Ceereceernenonns 14 2.,4.6 Draln Tank Systems «...ceeeece. eereseeraasanc 17 2.4.7 Piping and Flanges ....eceeescescarescncsanae 17 2.4.8 Heatlrs .v.ieeeeeeen. Meecseriaesensetasecnnns 19 2,4.9 ‘Materials ....... Ceeresssens e ieeas ceennas .o 19 2.4.10 Cover- and Off-Gas System ceviaes cereesasnans 19 - 2,4.11 Instrumentation and Control Systems ......... 21 2.5 Fuel ProCesBing ..iceieeeineneerossscascssncncnssosnss 23 2.6 Plant Arrangement .c...eeeeeeeesscnecvecoscssccconcnens 24 BOSITE 0 s a8 9 @ ..7."...'7‘ oooooooooooooo & s % 3 00 e e n T O S QB O 2 bR e 2'7 4. PLANT -.-oooooc...-.n.o.oor-nuoo'oopono.noo.--‘o....o. ------- 35 . 4.1 Geneml..Dt'rllttiIID.O.-."...‘,.Q.... lllllllll * o2 5 00 » 35 4‘2 Offlces -..........l........... . 0 » ®* 4.0 ® . ® - ® & 38 4.3 Building ...... * " o 8 5 & 8 e o 8 ¢ & e d * 2 & 8 9 & . &0 * P & & 80 . 38 4.3.1 . Reactor Cell ..ecvvee.. teeeseeans ecessenerase 43 493.2 Drain T&nk cell ® 9 & 6 B 3 ¢ &% 4B S 80 S8 4 S ¢ F TS B E P FES 47 4,3.3 ' Coolant Cell and Coolant Drain Tank Cell .... 51 ‘QBA-;fixfialEmummntmmm..Hr”.“.”.“.”.” 53 4.3.5 Pm Room ..‘C..'I.Qll...t'.‘...l...‘.“.-... 54 4,3,6 Service Tunnel ...... cestacreseseesessasanees 54, 4,3,7 Transmitter Room.and-Electric>Service Aress . 55 4,3.8 Auxiliary CellB ..ciceeeeeescescssanccnsonses 55 4.3.9 High-Bay Containment Enclosure .......ecceeee 56 4.3.10 Maintenance Control ROOM ...veeeeovovoncss .oe 58 xii Page 4.4 Off-Gas ATea ......iiveiiiiiiiiiiiiann. Ceerierieaaes 58 4.5 BtECK ATEE «iiiieieeririoearoneotssonatrtsrnenernonss o . 60 4.6 Vapor-Condensing Tanks ..... Ceesectcsanaeans teossscas 60 4.7 :Blower House ..... treeescacann et etir ittt ananos . 60 4.8 Store Room and Cooling Tower ........ Cheeirecene coes 61 4.9 Diesel HOUSE ....veevesonss Cescecaennn Cereenees s ces 61 4.10 Switch House and Motor Generator House ........ ceveas 62 4,11 Inlet Air Filter HOUSE s.vevvvrrenvennnnnn et 62 FUEL CIRCULATING SYSTEM .vvveveerscannsas Ceeeeeeaaaes ceeves 63 5.1 "Layout ...eceveen ceseceteeeernnnne cesncsnnn tresssscan 63 5.2 _Flowsheet ........ Ceesasens Ceersintaaens ceerean ciesanes 66 5.3 Reactor Vessel and Core Cecretaetseern e ceeean cecee 75 5.3.1 Description ....cccieeuene Gt eieteitrteecatannn 75 5.3.2 Graphite ......... Cieceticinersarannana R 86 5.3.3 Fluid Dynamics, Temperature Dlstrlbutlon and Solids Deposition .....cv.veevnven ceesses 20 5.3.3.1 General .....ceceecevnen tesetonaann .90 5.3.3.2 Model Studies ........... ctescerean ol 5.3.3.3 Overall Pressure Drop Across Reactor ......vvvee cereareronens . 91 5.3.3.4 Flow Distributor .......cecvveevn.. 93 5.3.3.5 Cooling Annulus ......vcveven. e 93 5.3.3.6 Lower Head ....c.iveeecececennoccns 96 5.3.3.7 COTE tuiiviviereneseneennncanes ceaee 98 5.3.3.8 Upper Head ........... e rereeees .o 103 5.3.4 Reactor Access Nozzle, Plug, and Strainer ... 104 5.3.5 Control Rods .c...vveenene Cheeeaaeaean ceaeeen 106 . 5.3.5.1 Introduction ............. ceanaen .. 106 5.3.5.2 Description ...c.ceeiieriicncancann .o 107 5.3.5.3 Control Rod Worth .veevievsecnnnnns 112 5.3.6 Graphite Sampler ......... Ceserarsctsrasnne . 113 5.3.7 Mechanical Design of Reactor Vessel ......... 118 5.3.8 Tubes for Neutron Source and Special De- tectors teviienrrieiininseanns teesiseesanas . 121 5.3.9 Support ........ testenanes Ceceseesssseresanen 122 5.3.10 Thermsal Shield ......... Ceecscseanns cesteanas . 125 5.3.10.1 Structural .............. e eeaann . 127 5.3.10.2 C00LliNg .vevevieresneeocnoosaonnnss 129 5.3.10.3 Mechanical Desigh ..c.evveere. 130 5.3.10.4 Shielding Considerations ....ceees. 130 5.3.11 Heaters ....... cresneen et etet et ches 131 5.4 Puel Circulating Pump ..c...... Ceceeanane ceveees ceses 133 -)' i - 5t5 -z 5.6 ‘!_ | u:ur xiii Description ....... e iefirtercatsarertencensnne 5.4,1.1 - Rotary-Element Assembly ........... 5\4.102 ‘Pump BOWl R E R R R RN R EEEREERE] - 5.4,1.3 Drive Motor ........... Cheseresians 5.4.1.4 Lubricating-0il System ............ 5'.40105 OilcatCh Ta.nk oooooooooooo YRR Hydraulics ..... Cecssessstetassaasstactscastnn Mechanical Design Considerations ............. 5.4.3.1 Volute and IMpellers ceceeeeeeeees. 5'403.2 Shaft ........... * 4 0 8 &6 89 B - * - 5.4.3.3 Bearings ...c.eeeercieneeen Ceetnees 5.4.3.4 Pump Bowl and NOZZ1€S ....oevevenn. Thermal-Stress Design Considerations ........ Pump Supports .......... rescaavatenns vesenras Heaters ..... Crestsseretararssaesaccconanaree Fuel-Pump Overflow Tank .veeeieenccscnoass ‘o 5.4.7.1 OVerflow PiDE veeveeernrencasaconns 5\4.7.2 OverflOW T&nk * 6 0% s e ¢ P 8P 0PI RS T - 5.4I7.3 Ta!lksupport ® 5 & & 4 v b ¢ & e 9 e *® s B v &8 Fuel Heat ExXchanger .....cciiveiernncecenseoenneaasas . Description sovveveinennne. testsateseseane s . Design Considerations ............... veseseen - .5.5.,2.1 Heat Transfer ........... cesessenee 5.5.,2.2 Pressure Drops «e...cecevenn ceeasan 5.5.,2.3 Stresses .e..... Cieeesceansaesanans . 5.5.2.4 Vibration ....ceevevennn cheesencana SUPPOTrtE t.vieivcnnnnernereannnnnnsn cesvenne oo ‘Heaters ....... evees Cesecesasteettasenenans . rimary’Circulating System.Piping,’Supports, Heaters, Insulation, Freeze Flanges and Freeze Valves TR eR S A AP RS e T SR e e 88 4SS S PSS Piping ...’.'....I..O. ......... ® 8 x & O B S O ¢ v - Piping Stresses and Flex1billty'Analysis ceee " BUPPOrtS scesiensenss Freeze Flanges ;.};........................., 5.6. .l FLlONEEE vetiitirecenecctncnrenconns 5. .2 Ring Gasket ..... cresiersasaas veses 5, .3 Balt SCreen ...ceveveeceroconenaens - 5,6. 44 Cla.mps ceisesvssrareses sescsranacen 5.6.4.5 Clamping Frame ...... sieteransans .o 5.6.4.6 Gas Leak Rates During Thermal Cyeling vv.veveeerenenrenoccnnsnno Loading and Stresses ....ccveveeces Page 136 137 139 143 144 147 149 151 151 151 152 152 154 155 155 158 158 158 160 162 162 168 168 169 170 171 171 172 173 173 174 175 178 180 181 182 183 184 187 188 5.6.5 Freeze ValWesS cevveieeeennnesaosasosnsannsea .o 5.6.5.1 General Description ........... viee 5.6.5.2 Definitions of "Deep Frozen, Frozen, Thawed" ......c.eevuennn . 5.6.5.3 ThermoCouples .....icoeceeveecennens 5.6.5.4 Freeze Valve 103 .....veveiveeenens 5.6.5.5 TFreeze Valves 104, 105 and 106 . 5.6.5.6 Freeze Valves 107 108, 1Q9, 110, 111 and 112 ....ciieiinnnnonn 5.6.5.7 PFreeze Valves 205 and 206 ....v.ve. 5.6.6 Pipe Insulation and Heaters ..e.iviineereneeas 5.6.6,1 General Description and Design Considerations ....veeveeceecesea . 5.6.6.2 Pipe Heaters ....... eratessane veene 5.6.6.3 "Thermal Insulation ....ceeveeese . 5.6.6.4 Pipe Line Thermocouples ........... FUEL DRAIN TANK SYSTEM .evievecatntnceeanensosssnanssnnneenns 6.1 General Description and Layout ........ccveveceesenns 6.2 Flowsheet .....ceeencecnccescccnnosnan eeseastacaseseea . 6.3 Drain Tanks Nos. 1l and 2 ......... Cecesisssinrcanseane 6.3.1 Description..c.ccvirrircecanann . fieeercene 6.3.2 DesSign eeviiiieinrincvancnenan ceereenscaasans 6.3.3 Decay Heat Removal System ................... 6.3.4 Drain Tank Electric Heaters and Tnsulstion .. 6.3.5 Supports for Drain Tanks .e.veveieesnens sees 6.4 PFuel FIush Tank ....cceceeeccncacses teeenceee Ceeeiane 6.5 Salt-Transfer Pipe Line Supports cesrasesssseecsnen . SAMPLER-ENRICHER SYSTEM ¢ v coveneeeeresisacesasonosassneses 7.1 Brief Description of Operation ............ cees e . 7.2 Design Criteria .......... Gt et e tseer ettt eeeaananens 7.2.1 Sampling ........c.0c... Ceves et satacnernnnnne 7.2.2 Enriching ....veeeeneeereeseencanns . .o 7.2.3 Poisoning .......cec0nnn.e cesrereee teseseenna 7.2.4 Addition of Contamina.nts e tereeaen Cerecnes 7.2.5 ‘Containment ...... C e et eseet et ene et rnenan 7.2.6 Stresses .....v... reeteeeaas Creceecasecrenas 7.3 Description of Equipment .....evveivieereennrenes beos 7.3.1 Capsules ....vcavee cietssnencns . o cecennan 7.3.1.]1 Bampling Capsules ....... ceceiaas . 7.3.1.2 Enriching Capsule ..... Creterreanea xiv Page 190 190 193 193 194 196 198 201 205 205 - 208 215 218 220 220 222 226 226 234 234 237 238 240 242 244 244 245 . 245 246 246 246 247 247 247 247 249 iy o -, & {0 N -y iH Page 7.3.2 Capsule Latch and Latchkey ....eecvivvnnennnns 249 7.3.2.1 LatChKey ..oveeveennennsecnsesnnneae 250 7.3.2.2. Latch ..c..uiiieiiiiiiineienenennen. 250 7.3.3 Cable ...viiiiinienennannnns Creareterareeseenns 250 7.3.4 Pump Bowl Equipment ........ feetecanas Ceerenan 250 7.3.4.1 Capsule Guide Cage ...uviseviennanns 250 7.3.4.2 Lower Latch StOD e.eeevcoceeneenns .o 252 | 7.3.4.3 Baffle ......... Ceteectestcananaanns 252 7.3.5 Transfer TUbe cev.iivirirtrrvnnerorsassonsassoss . 252 7.3.5.1 Expansion JOInt ..i...ieceieennesions 252 7.3.5.2 Bleeve ...civvvriannss BT 254 , 7.3.5.3 Upper Terminus .e..eivesveescesanoas 254 7.3.6 Operational and Maintenance Valve BOX «.vvvnnn 254 7.3.6.1 Valve BOX «..vviuiennneennosnencnnnns 255 7.3.6.2 Valves vovvevenvernnnns Cveeeeseranee 256 7.3.7 Transfer BOX «..veeeesceceennns e reeeeieeiaeea 256 7.3.7.1 Capsule Access Chamber ......c.cvees 258 7.3.7.2 Capsule Drive Unit and Box ........ . 259 7.3.7.3 Transfer Box Layout and Con= truction ........ 000 setrasenn. 260 7.3.7.4 Manipulator ...... M ereemeresesananns 260 7.3.7.5 Viewing Ports and Periscope ........ 261 7.3.7.6 Cepsule Removal Valve .............. 262 7.3.7.7 Capsule Removal Tube Assembly ...... 262 7.3.8 Capsule Transporting Equipment ..........cvu.. 263 7.3.8.1 Sample Transport Container ......... 263 7.3.8.2 Transport Container Removal Tool ... 263 7-3-803 Tr&nSPOI‘t C&Sk AR R R RN “ s 00 264 7.4 ’ containmént ;.0.‘.'.‘.‘.Il‘lh.'.l“..‘........l..‘“ll."‘.' 264 : 7;5 Shielding -.a-'-eeioonoooii._oo-nhou.‘---oaoocb-o‘-oo-u'.o-- . 267 . 7.6 SLresses ...iciiiiiiiiiiiiananaans eeeensiveacenee ceese 267 7.7 Cover-~Gas and Leak-Detection System ceescnassraes creene 269 7c8 Off"'G&S SYS'tem oooi ----- o.i..c...ootlo.td00.‘0.0.00.000 271 - 7‘8-1' SyStemNOCl r.-;'.'._..."._...... oooooo .dd‘o'-;oc'u..o 27-]- 7?8.2 SystemNO 2 !......I..0.0....i."“.'.......I.. 273 L 783 EXhB.uSt HOOd ..'..‘...",.'.' ------- o.;ooonot-.f.-oo 273 R 719 EleCtrical ..4-0.--.---....0--.---.'- --------------- seesn 274 7.10 Coolant-Salt Sampler-Enricher System',..._ ..... eerene . 274 COOLANT-SALT CIRCULATING SYSTEM «..vvvvnvnenn.. e 277 8.1 Layout and General Description .................. P 277 8.2 Flowsheet ......iieeeveneces Ceeee e Crtareesnnnaanann 279 10' xvi 8.3 Coolant-Salt Circulating Pump .e..veveeencenss eeees ‘o 8.3.1 Description ....... e erueraraens e, .. 8.3.2 HydrauliCS .ueeieeeeecsonecnaonas et raeaene . 8.3.3 OUresSes .u.vieveressencntsoroasocsntsnsccnna 8.3.4 . Pump SupportsS .v.eecicicnceraanas cevesaanans . 8.3.5 Heaters ....vcivivieennecenannas e tersseseeae 8.3.6 Thermal Insulation ................ reveses . 8.4 Radiator ......c...... C et teetieeaeeetee e 8.4.1 DescriPtion veiietnneneeerenarencasasonsanns . | 8.4. 1.1 COLL vvivninnnrenreennnnnnanencannns 8.4.1.2 Enclosure and Insulstion .......... : 8.4.1.3 Doors and Door Mechanism .......... 8.4.1.4 Cooling Air Blowers, Ducting and Dampers ......oeveeaes ceiseessenas 8.4.2 SLress ..eiieiecrcnenciannanen ettt 8.4.3 PerfOrmANCE ...vivierenreroneiesocosoannannns 8.h.4 Heablers ..uviiiiiinnrinnneeennenas Cee s ca e 8.5 Cell Wall Penetrations for Lines 200 and 201 ........ 8.5.1 Reactor Cell Sleeve ..... el et 8.5.2 Anchor Sleeve .........ccveuuos cenerns s eeeaae 8.5.3 Shielding .ec.ereereccerencsacscasecsanannonos 8.5.4 Heaters and Insulation .......... e v 8.6 Secondary Circulating System Piping and Supports . 8.6.1 1Piping Stresses and Flexibility Analysis .... 8.6.2 Coolant-Salt Piping Supports ........cci0vvun. COOLANT-SALT STORAGE SYSTEM cevvvcvcvrerssn eee e .o 9.1 Layout and General Description ............ v ree e 9.2 Flowsheet ...ciiiiierererenroreresrserasssnstonnnanssns 9.3 Coolant-Salt Drain Tank .....v.vveveceecconnes . . 9.3.1 Tank ® 4% & & ® & 5 ¢ e 9 & & 50 v 2 H s e b eSS o * 4% B 9 9 e B 8 e 9.3.2 Supports and Weigh Cells ............ ceereee . 9.3.3 Electric Heaters and Insulation ............. 9.3.4 Thermocouples coeeeveceennens e teeerans . 9.4 Coolant-Salt Transfer Line 203 ......vievevcorerennns 9.4.1 Upper Flange on Line 203 ....ovvivvernnnnnnn. 9.4.2 Lower Flange on Line 203 .......... Ceiacenaan COVER~GAS SYSTEM .0 ieecenconaorosnasearonnnoeas seernvvena 10.1 Layout and General Description ........eciveveaees e 10.2 System Requirements .......iciuieveenerenrnnrsnnennns . 10.3 Flowsheet ....... Ceeeeas Gt et eeteanetieenasenenans e . Page 285 285 289 289 289 291 291 291 292 292 297 297 299 300 300 308 309 309 309 310 310 311 312 312 315 315 316 318 318 319 321 322 323 323 323 325 325 325 327 {Yy}) * 11. X 12. ¥ : xvii 10.4 Helium Supply ..e.ceveverens, cessesaasnass cecestennn 10.5 Dryers cevevececas e eaen Nt eesascsscertseressaenaa .o 10.6 Preheaters .....cevevesenns Cecesesereseans Ceeens oo 10.7 Oxygen Removal Units ......... O eesseeeses 10.8 Treated-Helium Storage Tank .c.ceevevecesoceoncncnns 10.9 Bubblers for Indicating the Salt Levels in the Fuel and Coolant Pump Bowls Overflow Tank .eeeeece. "10.9.1 Layout and General Description ........seaes '10.9.2 Containment Tank .....cceceeeees P 10.10 Piping, Valves, and AppurtentnCes .eceeeocoevesscnss LEAK DETECTOR SYSTEM 4 vt v evvevesocnecnsaseessesssesaeasnsns 11.1 Nayout and General Description ............ ieesrenas 11.2 Flowsheet .........0... et seeteassecssannen teesacnas . 11.3 Headers ....eevsss crsssersevansa Ceerttiereetnanriene 11.4 VAlVEE tveeevenesctostoassasescsssossnnnnesns sesseene llo5 Disconnects S 8 0 5 8 S 0P B PRt AE N eSS Tt As e . = 11.6 Tocel Leak Detectors ...ivievvivovscncans tesesersens OFF-GASDISPOS-ALSYSIM .-.0....;0.00.0...Q...'.'.O;tl..l.rfi.v 12.1 lLayout and Genersl Description .......... e 12.2 FlOWSheet ...... .lllll...l...'...-.‘.l...‘I‘..O..C'l. 12.3 Holdup VOlumes ......ccveesan veesestoanne chssesneras 1204 Off-GaS Charcoal Beds oooooooooooooo ‘.o.oootoccpoo-.- 12.4.1 Main Charcoal BeAS seveeeeeereenerosnarssnns 12.4.2 Auxiliary Charcoal BedS .e.ivevevrenncsccnas 12.5 Piping, Valves and Filters .......... e eeeeeaenenas 12.5.1 Piping cveveorsecrecscessesensassnsnnsscssons 12.5l2 vah]-ves e 8 e s 90 .0..!"...00‘0............... 12-5-3 Filters ..;NcQ.o-(;}o.ooooo..}-.oooc;..t-.c- . 12.5.3.1 Porous Metal Filter in Line 522 .. 12.5.3.2 Porous Metal Filter in Lines | 524, 526, 528, and 569 .......... CONTAINMENT VENTILATION SYSTEM .;;...;.....f...;...;....f. 13.1 Layout and Genersal Description «v..eeeeene. eeeaeeens 13.2 Flowsheet ..u.cviiiieelioscsnnnseisncecarcacsonssens 13.3 Description of Equipment ....,.....;;......' ..... eee 13 3 l InletfiAir Filter Houseloo-.oto-o-dao;.q;tono l_13 3 l l House ;o(.f..oooooo.o-;o1;;;,ooo-o 13 3 l 2 Heating COilS oo-o-uo-orfiq-o;---o 13 3.1.3 Air-Supply Filters ....cceceensnss 3.3.1.4 LOUVETrS ...cvvencennsn reesseassens 13 3.1.5 Dampers and Ducts ....vvveviireres Page 332 232 333 334 336 337 337 338 339 344 344 349 352 353 353 355 356 359 361 368 369 369 374 376 376 376 377 377 377 383 183 387 391 391 391 392 392 392 392 14, 15. 13.3.2 Liquid-Waste Tank Blower .....ccieeeeevoses 13.3.3 Vent HOUBE ..ivvereinerassssosresavsssnsansans 13.3.4 Pilter Pit ... ieeivvrovrsacnccnnnas esessne 13.3.4.1 Roughing Filter ..... .. ceenne 13.3.4.2 Absolute Filters ..c...ece.. cens 13.3.5 StACK FANS cvvevvevonnnennnconnans cens . 13.3.6 St8CK ceeevrroncccncnnscanse et cesene .o 13.4 Criteria ..... et eecaerorrecsecteccensttetartesatanne LIQUID WASTE SYSTEM . ccveerencsessccssssasssceossssenssasns 14.1 Layout and General Description ........ccieeveniens . 14.1.1 Liquid Waste Cell ........ecuuvunnn Ceeenans 14.1.2 Decontamination Cell ...... cesecceraisenns 14.1.3 Remote Maintenance Practice Cell .......... 14.1.4 Sump ROOMm «.vvvvvnninnnenrnrennceinronnnnns 14.2 FlOWShEEh .vveeveecasoarsscossassssavsanasassasnansasa 14.3 Description of Equipment ......ccceveeioenanennannns 14.3.1 Liquid Waste Storage Tank .......ccccevevean 14.3.2 Waste Filter ....cieiieerenerecesennsnnanns 14.3.3 Waste PUMD ccvverrrrarocssanonnensasasaans . 14.3.4 Sump PUMPS ceevverecatosncacancessessansanea 14.3.5 Pit PUBIP eveecvonvcccscnscncnarosensosasses 14.3.6 Jet PUMPS cvvevveercvoacencnnans Ceeeienaene . 14.4 Design Criteria ...co..... ceeeone e cerieenen COOLING WATER SYSTEM .o.uuevnrnianrensanssnennsencsnesnennns 15.1 Layout and General Description .e....ocieeecieenanns 15.2 FLOWSHEEE vvveeenetcecsraocoaassacaoscnsssossssnssensse 15.2.1 Potable and Process Water ............ . . 15.2.2 Cooling Tower Water System ........c.v00.... 15.2.3 Treated Water System .....vociiiiiinnnnn.. . 15.2.4 Condensate SysStem ....c.ceeeeeeevencascasen 15.3 Description of Equipment .....ccecceecncasveasosrsoass 15.3.1 Condensate Storage Tank No. 1 ........vv0. . 15.3.2 Condensate Storasge Tank No. 2 ...... cieenes 15.3.3 Treated Water Surge Tank ........ Ceeeeee ces 15.3.4 Cooling TOWer ......ecevecanss eeeesssestones 15.3.5 Treated Water Cooler ........iiiieteenanes 15.3.6 Treated Water Circulating Pumps ....... . 15.3.7 Cooling Tower PUMPS ..cvivvevevncenas ceieena 15.3.8 Steam Condenser for Condensate System ..... 15.3.9 Space CoOlers ....civevevtoccnssassancans .o xviii Page 393 393 393 393 394 39 394 396 397 397 397 397 398 398 398 404 404 404 405 405 405 405 405 408 408 410 410 412 413 416 416 416 417 417 417 418 418 420 420 420 LY (o o g o - S e Y P! 16. 17. 18. 19. 15.3.10 15,3.11 Treated Water Filter xix 15.3.9.1 Coolant Cell Coolers ...ccveeevee 15.3.9.2 Reactor and Drain Tank Cell Space CoOlers sieiveraaacas hese Piping, Valves and Appurtenances .......... 15.3.10.1 PiPiNG +'rvvvnvrnrencnnrencencans 15.3.10.2 Valves ..... 15.3.10.3 Backflow Preventers ceceseeneens 15.3.10.4 Strainer COMPONENT COOLING SYSTEMS «evvvvvrvnearancanns cheeeaanes .. 16.1 General Description and Layout ........ crressenenaas 16.1.1 Circulating Gas System .......... e . 16.1.2 Cooling Air Supply ...eoce.e. ceeseernsaanen . 16.2 Flowsheet ...oveeeen. e tereerneaeae. crvnnas cenees 16.3 Description of Equipment ......ce0veee.s ceseees cesee 16.3.1 Gas Blowers CCP-1 and CCP-2 and Con- _ tainment Tanks ........... tessscnana sescas 16.3.2 Air Blower, CCP-3 ...... Cireeeesacns ceeraas 16.3.3 Gas Cooler, GC ....... ret i esecasiensuoces .o 16.3.4 Valves ......... cessasaanes cisrencans cessea 16.3.5 Piping .evvvveevcannas cecesereacasnes cesees CONTAINMENT ......cceeeeee eetetesssatsavrseseenstsssnenenens 17.1 General Design Considerations ...... , cesesssenus 17.2 Reactor and Drain Tank Cells .....ceeevevecccnes coee 17.2.1 Cell Leak Rate .......... Heesasvecssssnnesns 17.2.2 Cell AUmMOSPhETe . sieeerescnnsssoarsacsscsss 17.2.3 Penetratlons end Methods of Sealing ....... 17.3 Vapor Condensing System ;..:..,..........,. ......... BIOLOGICAL SHIELDING e eeereereeieeeeans certettenenaesens . 18. 1 General Description......,:_ ....................... ‘o ELECTRICAL. SERVICES .......,...' ......... Ceesanans P 19.1 - General Descrlption Crsesasieses s eerecsrnssasnene s - 19,2 Transmission Lines and Substation crcasaan sesecssees 19.3 Emergency Diesel-Generators .....c..cieeceveencenees . 19.3.1 'DleSél-Generator'Units ‘No. 3 end No. 4 .... -19.3.2 Diesel-Generator Unit No. 5 eeeceene cisesses 19.4 Process Electrical Circuits .. 19.4.1 Switchgear Equipment ® 9 & ¢ & 0 & & 58P SO OB s s A s e 0D Page 420 423 423 423 423 424 424 4217 428 428 428 430 430 434 434 436 436 436 438 439 439 440 441, 441 442 449 450 453 454 459 460 460 461 462 462 19.5 19.6 19.7 19.4.1.1 TVA Switchgear Bus and Current- Limiting Reactor ........... cene 19.4.1.2 Switchgear Bus No. 3 ....ccven .o 19.4.1.3 Switchgear Bus No. 4 ...... ceeees 19.4.1.4 Switchgear Bus No. 5 .veivivenens 19.4.2 Motor-Control Centers .u...ceveeceenensesans- 19.4.2.1 TVA Motor Control Centers ....... 19.4.2.2 Generator No. 3 Motor-Control : Center ...vvivieececnctecencnces 19.4.2.3 Generator No. 4 Motor-Control Center .i.viiivieirreesnrasvessns .. 19.4.2.4 Generator No. 5 Motor-Control Center ..... teeresiesoaieatanes . Building Service Circuits ......ccivivvieensns creaes . 19.5.1 Building Service Panel No. 1 .......0.. ceens 19.5.2 Building Service Panel No. 2 .....ceiececens Direct-Current Electrical Systems ............. caoens 19.6.1 Battery, M-G Set and Distribution Panel for 250-v DC System ....cvvvecinininnenens . 19.6.1.1 AC-DC, 125-kw, 250-v Motor- Generator Set MG-=1 ....cecevvene 19.6.1.2 Battery .....c.ciiiiiiiinenns oo 19.6.1.3 Distribution Panel ....cecee0v.. .. 19.6.2 Battery, M-G Set and Control Panel for 48-v DC System ..civvvevecrenasessess cereean 19.6.2.1 AC-DC, 3-kw, Motor-Generator Sets evieveinennriannes ceeceseans 19.6.2.2 Battery for 48-v System ceserenoe 19.6.2.3 Control Panel for 48-v System ... 19.6.3 = DC-AC 25-kw Motor-Generator Set MG-4 and Connected Load ........ e cesecsceseacennss .o Heater Control Circuits .. ierie it eieereoeronnoasns . 19.7.1 Circuit Breaker Panels G5-1A, G5-lC G5-1D, T2-V and T2-W cccvirererinvennnnssns 19.7.1.1 Transformers G5-1A and G5-lC 112.5-KVa cevenvene . . cens 19.7.1.2 Transformers G5-1D, T2-V and T2-W 75-kva *P e G I eSS BPIEBEIBRESSESS 19.7.1.3 Circuit Breakers ......co0000 cees 19.7.2 Circuit Breaker Panels G5-BB, T1-A, T1-B, Tl-C, T2"Y and G'5—2Y ------------- 4 00 cane . Page 462 465 465 465 467 467 467 467 471 471, 471 471 476 476 476 476 477 477 477 477 477 477 479 479 479 479 480 480 - \ ot xxi ié.?.B - Circuit Breaker Panels G5-2X and Drain Line 103 Heater Circuit .e......... ® s 8 e 080 19.7.3.1 Saturable REACEAT vvveennnnns ‘e 19.7.3.2 Special 25-kva High-Current Transformer .....cecoeeveces . 19.7.4 Heater Control Panels and Equipment ..... | 19.7.4.1 Type 136 "Poverstat” ........... 19.7.4.2 Type 1256 "Powerstat" .......... 19.7.4.3 Motor-Operated Type 1256-1035 "Powerstat” ........ et eeeene 19.7.4.4 Induction Regulator ............ 19.7.4,5 Three-Phase 30-kva Transformer . - 19,7.4.6 . Single-~Phase 10-kva Trans- S i o5 4 17} of - J Ceereenes 19.7.4.7 Heater Breaker Panels .....c.... 19.7.5 Heater ILeads .....ceves. heeescceneransns ‘e 19.8 Cell Wall Penetrations for Electrical Ieads ........ 19.8.1 Sheathed Cables .,...... G eeetrecaesenen vass 19.8.2 Cable Sleeves ...... Cecieerertececans Cenes 19.8.3 Reactor Cell Penetration Plug and Sleeve .o 20. BUILDING SERVICES beeataeae e st enterteseceenscacnanes 20,1 POtabLe Waber vu.veeerereenenrennereonneeranoanss ces 20.2 Process Water .............. bes s et sessseersene . 20,3 Bullding Lighting .........e.000ven secsasses vesens . 20,4 PenCing ..veieeieciceriniseeraeacsasssnnsanas sereann 20.5 Steam Supply cececeecoonn.. seesersaaneas ceterenanens 20.6 Roof, Foundation and Floor Dralns teserecrearanann .o 20-7 SBIlit&ry DiSPOSal S 99 S0 99 O ST EE e BN s 0 0 9 080 e 2008 AiI' Conditioners R R R N R 20.9 Fire Protection System .......... enaann “ereecsseose APPENDIX v vennsnsenneenssonesnesescaineensnnnss AT ceeenn . ‘List of References Used inPart I eovenne e e . Abbreviatlons s e b e ctsasesssestacsnas st asarasnsnsasna s beos Equipment and Location Abbreviations ceeseesavenes . Symbols Used on- MSRE Process Flowsheet® ............ Cereaene Synibole Used in MSRE Drawing Identification Number . ....... Page - 480 480 481 481 481, 490 490 490 493 493 493 494 502 502 502 506 506 506 508 508 508 209 509 509 509 513 515 526 529 532 534 «~ - PFig Fig. Fig. Fig. ‘Fig. Fig. - Fig. Fig. Fig. Fig. Figi " Figo Fig. _Fig, Fig. Fig. Fig. 'Fig, Fig. ~ Fig. Fig. . Fig. Fig. Fig. Fig. Fig. TR.1 2.2 2.3 2.4 2.5 2.6 3.1 3.2 3.3 . 3.4 3.5 4.1 4.2 4.3 4.4 4.5 4.6 4.7 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 xxiii LIST OF FIGURES Reactor Vessel in Transport Jig Prior to Instal- ~ lation . Construction Photograph MSRE Reactor Cell MSRE Flow Diegram Reactor Vessel MSRE Fuel Pump Primary Heat Exchanger Radiator Coil and Enclosure Fuel-Salt Drain Tank ORNL:Area Map ‘Plot Plan Molten Salt Reactor Experiment Building 7503 Potable Water Supply to MSRE - Electrical Distribution System to MSRE Steam Supply to MSRE Front View of Building 7503 Rear View of Building 7503 During MSRE Construction Plan at 852-ft Elevation - Plan at 840-f£t Elevation - Elevstion Bulilding 7503 | : Shield;Block Arféngement at Top of Reactor Cell ‘Block Arrangemgnt on Top of Drain Tank Cell Reactor Cell Plan - | Reactor Cell Elevation *Fuel-Salt\System;Process;Flowsheet . Cross:Sectidn?MSRE“ReactoriVessel and. Access : Nozzle \ ' " Elevation of Cohtrol,30d~DriVE‘HbuSings Typical Graphite'SfiringerlArrangement Lattice Arrangement at Control Rods Graphite-INOR-8 Sample Assembly Full-Scale_Model of Reactor Vessel Page iii iv 10 13 15 16 18 28 31 33 34 36 37 39 40 41 45 50 64 65 67 76 77 80 82 83 92 Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 5.10 5.11 5.12 5.13 5.14 5.15 5.16 5.17 5.18 5.19 5.20 5.21 5.22 5.23 5.24 5.25 5.26 5.27 5.28 5.29 5.30 5.31 5.32 . 5.33 5.34 2.35 6.1 6.2 XXiv Pressure Drop Through Reactor Core Centerline Velocity Distribution in Volute of MSRE Full-Scale Model of Core Flow Distribution in Reactor Core Fuel Passages at Total Flow Rate of 1200 gpm in Full-Scale Model Control Rod Poison- Element Control Rod and Drive Assembly Diagram of Control Rod Drive Schematic of Reactor Access Shown Ready for Re- moval of Specimen Assembly Work Shield for Graphite Sampler Criteria for Establishing Static Design Stresses in INOR-8 Reactor Vessel Hanger Rods Thermal Shield Prior to Installation Exterior View of Fuel Pump Showing Flange Bolt Extensions Fuel-Salt Pump Bridge and Impeller Seal Clearances Lubricating 0il System Flowsheet Hydraulic Performance of Fuel Pump Fuel Pump Support Fuel Pump Overflow Tank Primary Heat Exchanger Subassemblies Tube to Tube-Sheet Joint in MSRE Primary Heat Exchanger Freeze Flange and Clamp Freeze Flange Clamping Frame Showing Assembly and Disassembly Freeze Valve and Line 103 Freeze Valve and Lines 107, 108, 109, 110 Freeze Valve and Lines 111 and 112 Freeze Valve and Lines 204 and 206 Removaeble Heater for 5-in. Pipe Fuel Drain Tank System Process Flowsheet Fuel Processing System Flowsheet Page 9% 95 99 108 109 111 115 117 120 123 126 134 140 145 150 156 159 163 167 179 185 195 199 200 202 204 223 227 o ) \b‘ ¥4 Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig, Fig. Fig. Fig. 6.3 6.4 7.1 7.2 7.3 7.4 7.5 7.6 7.7 8.1 8.2 8.4 8.5 8.6 8.7 8.8 8.9 10.1 10.2 10.3 11.1 11.2 1103 V' 11.4 11.5 12.1 12.2 Fuel Drain Tank Steam Dome Bayonet Assembly Bayonet Cooling Thimble for Fuel Drain Tank Sampling (léft) and Enriching (right) Capsules Sampling Capsule Cable Latch Schemetic Representation Fuel-Salt Sampler- Enricher Dry Box Capsule Access Chamber Trensfer Cask for Sampler-Enricher Transport Container Effect of Thickness on Effectiveness of Sampler Shielding Flow Diagram of Cover-Gas, Off-Gas and Leak Detection Systems for Sampler-Enricher Coolant-Salt System Process Flowsheet Performance Curves for Coolant-Salt Pump Radiator Coil Configuration Radiator Tube Matrix Radiator Tube Supports Characteristies of Radiator Duct Annulus Fans Radiator Air Flow Characteristics Radiator Air Flow Characteristics at Various Steps in Load Regulation Estimated Performance of Both Radiator Supply Alr Fans Operating in Parallel Flow Diagram of Cover-Gas System Cover-Gas System Process Flowsheet Oxygen Removel Unit Cover-Gas System General Routing of Leak DetectoriLines ‘Schematic Diagram of Leak-Detected Flange Closure Method of Utilizing One Leak Detector Line to Serve Two. Flanges in Series = = - Leak Detector System Process Flowsheet ‘Leak»Detector System.Block Disconnects with Yoke Schematic Diagram of Off-Gas System Off-Gas System Process Flowsheet Page 231 232 248 221 253 257 265 268 270 280 290 293 294 295 301 303 304 306 326 328 335 346 347 - 348 350 354 360 363 Fig. Fig. Fig. 'Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. 12.3 12.4 12.5 12.6 12.7 13.1 13.2 14.1 15.1 15.2 15.3 15.4 15.5 17.1 19.1 19.2 19.3 19.4 19.5 19.6 19.7 19.8 19.9 20.1 XxXvi Activity of Fission-Product Isotopes of Xenon and Krypton In Pump Bowl Off-Gas Estimated Charcoal Bed Temperatures as Function of Flow Rate Through the Bed Concentration of Xenon and Krypton at Off-Gas Stack Outlet Maximum Estimated Temperature in First Section of Charcoal Bed vs Pipe Diameter Porous Metal Filter in Off-Gas Line 522 Schematic of Air Flow Diagram Containment Ventila- tion System Stack Fan Performance Curves Liquid Waste System Process Flowsheet Cooling Water System Process Flowsheet Characteristic Curves — Treated Water Circulating Pumps Characteristic Curves — Cooling Tower Water Circu- lating Pumps Cross Section Backflow Preventers in Water Lines 819 and 890 Capacity of Backflow. Preventers in Water System Diagram of MSRE Vapor-Condensing System Simplified One-Line Diagram of Electrical Supply System Process Equipment Electrical Distribution System Building Services Electrical Distribution System Location of Equipment in Switch House Typical Schematic Diagram for Type 136 Powerstat Typical Schematic Diagram for Type 1256-1035 Powerstat Motor-QOperated Motor-Operated Induction Regulator Male and Female Electrical Disconnects for Heater Leads Inside Cells Typical Electrical Lead Penetration of Reactor Cell Wall Water Services to Building 7503 Page 370 371 372 375 385 395 399 411 419 421 425 426 445 455 456 458 463 482 491 492 495 505 507 ™ Fig. 20.2 Schematic Diagrem Building 7503 Drainage System Fig. Fig. A.l A.2 Xxxvii - Symbols Used on MSRE Process Flowsheets Symbols Used on MSRE Process Flowsheets Page 510 532 533 M}‘?t 2! Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table = @™ O MDNWN WD ERE WM Moo v owow H O . o n o l._J 5.12 5,13 6.1 6.2 6.3 6.4 7.1 8.1 8.2 8.3 xxifi / LIST OF TABLES Composition and Physical Properties of the Fuel, - Flush, and Coolant Salts Composition and Properties of INOR-8 Reactivity Requirements Reactor Cell Penetrations Drain Tank Cell Penetrations Auxiliary Cell Dimensions Distribution of Helium Supply to Fuel Pump Reactor Vessel and Core Design Data and Dimensions Properties of MSRE Core Graphite — CGB Summary of Reactor Physics Data Fuel-Salt Circulation Pump Design Data Lubriceting-0il System Design Data Lubricating 0il Properties Estimated Stresses in MSRE Fuel-Pump Shaft (psi) Design Data for Primary Heat Exchanger Variable Spring Supports for Fuel and Coolant Selt Piping Inside Reactor Cell MSRE Freeze Valves MSRE Pipe Line Heaters Thermal Insulation on.MaJor'MSRE Selt Piping Design. Data for Drain Tanks No. 1 and 2 ’Design Data for Condensers in Drain Tank Heat Re~ - moval Systems - , . Design Data for Fuel System.Flush Salt Tank _,Salt Transfer Pipe Line Supports B Helium: Supply Lines and Restrictors in. Fuel-Salt Sampler-Enricher System Coolant-Salt Circulating Pump Radiastor Design.Data . | Possible Steps for Controlling Heat Removal Rate from the Radlator Page 20 22 48 52 57 70 78 87 101 135 146 148 153 164 177 191 209 216 229 236 24 243 272 286 296 307 Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table Table - Table Table Table Table Table Table Table Table Table Table Pable Table 8.4 9.1 10.1 10.2 10.3 11.1 12.1 12.2 12.3 12.4 12.5 13.1 14.1 14.2 15.1 15.2 15.3 16.1 16.2 16.3 19.1 19.2 19.3 19.4 19.5 19.6 19.7 19.8 19.9 XXX Coolant Cell Salt Piping Supports Design Data for Coolant-Salt Drain Tank Cover Gas System Hand Valves Cover Gas System Check Valves Cover Gas System Control Valves and Regulators Ieak Detector System Headers Design Data Off-Gas Disposal System .. Atom Flow Rate Emerging from Fuel Pump Bowl Off-Gas System Air-Dperated Valves Off-Gas System Check Valves | Off-Gas System Hand Valves Estimated Containment Ventilation System Air Flow Rates During Normal Reactor Operations (cfm) Lines Emptying into Sump in Room Sump Ejector Characteristics Equipment Cooled by Cooling Tower Water Equipment Cooled by Treated Water Design Data Reactor and Drain Tahk Cell Spacte Coolers Gas-Cooled Components . Air-Cooled Components Component Cooling System Valves Switchgear Bus and Bresker Data Connections to Switchgear Bus No. 3 Equipment Connections to TVA Motor Control Centers Equipment Connections to Motor Control Center G-3 Equipment Connections to Motor Control Center G-4 Equipment Connections to Motor Control Centers G-5-1 and G-5-2 | Connections to Building Service Panel No. 1- Connections to Lighting Distribution Panels 1A ~ i . and 1Al Connections to Building Service Panel No. 2 19.10 Heater Control Panels Page 314 320 340 - 341 342 351 357 373 378 379 380 384 403 406 409 409 422 429 431 437 464 466 468 469 470 472 473 474 475 483 " 1 r*. (ol Table Table Table Table ‘xxxi 19.11 Heater Electricsl Lead Cell Wall Penetrations 19.12 Summary of Flectrical Lead Penetrations in Reactor Cell - 19.13 Summary of Electrical Lead Penetrations in Drain Tank Cell 19.14 General Cable Company MI Caeble Numbers Page 1496 503 503 503 41 MOITEN-SALT REACTOR EXPERIMENT PART T DESCRIPTION OF RFACTOR DESIGN Volume I —ti, v &) C o % 1. INTRODUCTION The Molten-Salt Reactor Experiment (MSRE) was underteken by the Oak Ridge National Laboratory to demonstrate that the desirable features of the molten-salt concept could be embodied in a practical reactor that could be constructed and maintained without undue difficulty and one that could be operated safely and reliably. Additional important objectives were to provide the first large-scale, long-term, high-temperature tests in a reactor environment of the fuel salt, graphite, moderator, and high- nickel-base alloy (INOR-8). Operating data from the MSRE should provide important informetion regarding the feasibility of large-scale molten- salt reactors. Molten-salt reactors were first investigated as a means of providing a compact high-temperature power plant for nuclear-powered aircraft. In 1954 an Aircraft Reactor Experiment (ARE) was constructed at ORNL which demonstrated the nuclear feasibility of operating a molten-salt-fueled reactor at high temperature. Fuel entered the ARE core at 12000F and left at 15OOOF when the reactor power level was 2.5 Mw. Immediately after the successful operation of the ARE, the Aircraft Reactor Test (ART) was started at ORNL as part of the Aircraft Nuclear Propulsion Program (ANP). This test was discontinued in 1957 when the ANP Program was revised, but the high promise of the molten-salt reactor type for achieving low electric power generating costs in central power stations led ORNL to continue parts of the basic study programs. Features of the molten-salt concept which.deéerve special mention with regard to its future propecté_are: - ' : | 1. The fuél is fluid at.reattor temperatures, thus. eliminating the extra costs éssoéiated with the fabrication, handling, and reprocessing of solid fuelfelements.,.Burnup in the fuel is not limited by radiation damage or reactivity loss. The fuel can be reprocessed continuously in a side stream for removal of fission products, and heW-fiSSionable ma- terial cen be added while the reactor is in opération. 4 O 2. Molten-salt reactors can operate at high temperatures and pro- “w duce high-pressure superheated steam to achieve thermal efficiencies in the heat-power cycle equal to the best fossil~fuel-fired plants. The relatively low vapor pressure of the salt permits use of low pressure containers and piping. 3. The negative temperature coefficient of the reactor and the low excess reactivity are such that the nuclear safety is not primarily dependent upon fast-acting control rods. 4y, The fuel salt has a low cross section for the parasitic ab=~ sorption of neutrons, and when used with bare graphite as the moderator, - very good neutron economies can be achieved. Molten-salt reactors are | thus attractive as highly efficient converters and breeders on the Th-%333 cycle. 3 5. The fluoride salts used as the fluid fuel mixture have good thermal and radiation stability and do not undergo violent chemical re- actions with water or air. They are compatible with the graphite moder- ator -and can be contained satisfactorily in a specially developed high- nickel alloy, INOR-8. The volumetric heat capacity, viscosity, thermal conductivity, and other physical properties are also within desirable ranges. | 6. Use of relatively high circulation rates and temperature dif- ferences results in high mean power density, high specific power, and low fuel inventory. ' & These attractive features of the molten-salt reactor concept are partially offset by the disadvantages that: 1. The fuel salt mixture melts at about BhGPF, so means must be provided for maintaining all salt-containing portions of the system above this temperature. 2. The fluoride salts react with oxygen to precipitate fuel con- stituents as oxides. Although zirconium tetrafluoride is included in the salt mixture so that ZrO2 must be taken to prevent the fuel from being contaminated with air, water, will precipitate in preference to U02, care or other oxygen-containing materials. 3. The radiocactivity in any fluid-fuel system is in a mobile form, ‘” and special provisions must be taken for containment and maintenance. - LY During the period 1957-60, investigations were carried out at ORNL on the fuel salt chemistry, metallurgy of containment materials, the de- sign of salt-circulating pumps, and on remote maintenance techniques. The results of this work lent additional encouragement, and in 1959 studies were made by H. G. MacPherson® and L. G. Alexander 93_5;,2, pertaining to the applicability of the molten-salt concept to central power station reactors. The studies resulted in a proposal3 to the AEC for construction of a molten-salt experiment to investigate remasining areas of uncertainty that could be resolved only by actually building and operating a molten- salt reactor. In April, 1961, ORNL received a directive from the AEC to design, construct, and operate the Molten-Salt Reactor Experiment (MSRE), the subject of this report. Early in the design phases it was decided that the MSRE was to have as its primary purpose the investigation of the practicality of the molten- salt concept for central power station applications. As such, the MSRE was envisioned as a straightforward-type of installation, uncomplicated by the inclusion of experimental apparatus which might Jjeopardize relisble, long~term operation. It was also necessary that the MSRE be of a large- enough capecity for the experimental findings to be meaningfully extrapo- lated to the full-scale plants. It was decided that a reactor of 10 Mw thermal output would satisfy the criterion. | Conversion of the 10 Mw of heat to useful electricity was not con- sidered to be necessary to demonstrate the concept, so existing blowers and stack were used to dissipaté the heat to the atmosphere. Containment requirements dictated a'double barrier between the highly radiocactive fuel salt and the environment, and a salt very similar to the fuel salt in com- position and physiéal properties was chosen to transport the heat.from the fuel salt to air-cooled surfaces. | An expanded plant layout was adopted in order to provide access to equipment and to facilitatecmaintenance,operations, The MSRE was installed in an existing building in the 7503 Area at ORNL that was constructed spe- cifically-for>the ARE and ART. This arrangement provided some savings and expedited construction in that the building included a containment vessel which, with modification, was suitable for the MSRE. A significant amount of usable auxiliary equipment was also on hand, including air blowers and a stack for dissipation of heat to the atmosphere, emergency diesel- electric power supply, heavy-duty cranes, etc. Shop, office, washroom, and control room spaces were also available, and some of the heavy con- crete shielding was adaptable to the MSRE. Fitting the MSRE design to the existing facilities required numerous design compromises, but no ex- treme difficulties were encountered. Construction of the MSRE officially started in July, 1961, although much of the advance thinking and preliminary design work were well under way by that time. Major building modifications were started in 1961 and were completed by the end of 1962. Iack of funds and late delivery of the graphite moderator delayed installation of major equipment until early 1964 . The installation was scheduled for completion in the early summer - of 1964, and the target date to achieve criticality was set for the end of that year. v, 2. GENERAL DESCRIPTION 2.1 Type The Molten-Salt Reactor Experiment (MSRE) is a single-region, un- clad, graphite-moderated, fluid-fuel type of reactor with a design heat generation rate of 10 Mw. The circulating fuel is a mixture of lithium, beryllium, and zirconium fluoride salts that contains uranium or thorium and uranium fluorides. Reactor heat is transferred from the fuel salt to a similar coolant salt and is then dissipated to the atmosphere. 2.2. location The Experiment is located in the 7503 Area of the Oak Ridge National Iaboratory, Oak Ridge, Tennessee. The site is about one-half mile south of the main Iaboratory buildings, in a wooded, secluded bend of the Clinch River that is reserved for special reactor installations. 2.3 Fuel and Coolant Salts The composition and physical properties of various fuel and coolant salts are given in Table 2.1. Favorable neutron absorption and chemical and physical properties were important requirements for the compositions selected. Beryllium fluoride is used to obtain & low melting point. Lithium fluoride (99.99% 117 in both fuel and coolant salts) imparts good fluid flow properties to the mixture. Zirconium fluoride protects the fuel salt against precipitation of UO2 from contamination by air and moisture. Fuel salts containing throium are of interest for future large- scale thorium breeder reactors. The first experiments in the MSRE will be run with partially enriched uranium because there are fewer uncer- tainties concerning the chemical behavior of that fuel. Iater the reactor will be operated with the highly enriched uranium fuel and then with the thorium-uranium fuel. Table 2.1 Composition and Physical Properties of the Fuel, Flush, and Coolant Salts5 Fuel Salt Thorium— Highly En- Partially En- Flush and Uranium riched Uranium riched Uranium Coolant Salt Composition, mole % LiF (99.99+% 117) 70 66.8 65 66 BeFp 23.6 29 29.1 3k ZI‘FLI_ 5 5 - ThFu 1 0 -- UFh 0.4 0.2 0.9 -- Physical Properties, at 1200°F 1200°F 1200°F 1060°F Density, 1b/ft3, at 1200°F 140 130 13k 120 Viscosity, 1b/ft-hr 18 17 20 2h Heat Capacity, Btu/lb-°F 0.45 0.48 0.47 0.53 (at 1200°F) (at 1200°F) Thermal Conductivity, Btu/hr® (°F/ft) 3,21 3,2 3,2 3.5 Liquidus Temperature, °F 84o 840 840 850 = 2.4 Equipment and Process The major items of equipment in the MSRE are shown on a simplified flowsheet in Fig. 2.1. The fuel-salt-circulating system is the reactor primary system. It consists of the reactor vessel where the nuclear heat is generated, the fuel heat exchanger in which heat is transferred from fuel to coolant, the fuel circulating pump, and the interconnect- ing piping. The coolant system is the reactor secondary system. It consists of the coolant pump, a radiator in which heat is transferred from coolant salt to air, and the piping between the pump, the radiator, and the fuel heat exchanger. There are also drain-tank systems for con- taining the fuel and coolant salts when the circulating systems are not in operation. 2.4.1 Reactor The reactor vessel is a 5-ft-diam by 8-ft-high tank that contains 8 55-in.-diam by 64-in.-high graphite core structure. A cutaway draw- ing of the reactor is shown in Fig. 2.2. Under design conditions of 10 Mw of reactor heat, the fuel salt enters the flow distributor at the top of the vessel at 1175OF and 20 psig. The fuel is distributed evenly around the circumference of the vessel and then flows turbulently down- ward in a spiral path through a l-in. annulus between the vessel wall and the core can. The wall of the vessel is thus cooled to within about 5OF of the bulk temperature of the entering salt. The salt loges its rotational motion in the straightening vanes in the lower plenum and turns and flows upward through'the graphite matrix in the core can. The graphite matrix is an éssembly of vertical bars, 2 in. by 2 in. by about 67 in. long. Fissioning of‘235U in the fuel occurs as it flows in 0.4-in. by 1.2-in. channels that are formed by grooves in the sides of the bars. There are about 1140 of these passages. :The nominal core volume within the 55-in.-diam by 64-in.-high core structure is 90 ft3, of which 20 ft3 is fuel and 7O ft3 is graphite. At 10 Mw, and with no fuel absorbed by the graphite, 1.4k Mw of heat is generated in the fuel outside the nominal core, 0.6 Mw is generated in the graphite, and 8.0 Mw is generated in the fuel within the core. This 10 REMOTE MAINTENANCE CONTROL ROOM UNCLASSIFIED ORNL-DWG 63-1209R REACTOR CONTROL ROOM LW . REACTOR VESSEL . HEAT EXCHANGER . FUEL PUMP . FREEZE FLANGE . THERMAL SHIELD . GOOLANT PUMP DO LGN Fig. 2.1. MSRE Flow Diagram. RADIATOR . COOLANT DRAIN TANK . FANS . DRAIN TANKS FLUSH TANK CONTAINMENT VESSEL . FREEZE VALVE 11 UNCLASSIFIED ORNL-LR-DWG 61097R FLEXIBLE CONDUIT TO CONTROL ROD DRIVES SAMPLE ACCESS POR » w 2 3 x < © 2 J o o o ACCESS PORT COOLING JACKETS REACTOR ACCESS PORT FUEL OUTLET CONTROL ROD THIMBLES CORE CENTERING GRID FLOW DISTRIBUTOR GRAPHITE-MODERATORY, STRINGER FUEL INLET REACTOR CORE CA REACTOR VESSEL MODERATOR ANTI-SWIRL VANES SUPPORT GRID VESSEL DRAIN LINE Reactor Vessel. Fig. 2.2. 12 corresponds to an average fuel power density of 1k kw/liter in the nominal k=¥ core. The maximum fuel power density is 31 kw/liter. Flow in the coolant channels is laminar, but both the graphite and the fuel have good thermal conductivities, so the maximum temperature of the graphite is only about 60°F above the mixed mean temperature of the ad jacent fuel. The nuclear average and the maximum temperatures, respec- tively, of the graphite are estimated to be about 1255OF and l3OOOF. The temperature of the fuel leaving the hottest channel in the core is about 1260°F. | Fuel leaves the top of the reactor at 12250F and | psig through the side outlet of a special fitting designed as an access port for insertion of graphite and metal samples and for three 2-in.-diam control rod thimbles. The poison elements in the control rods are short hollow cylinders of gadolinium oxide 1 in. in diameter, clad with Inconel and arranged on a flexible Inconel hose to permit passage through two bends that form an offset in each thimble. The contrcl rods and drives are cooled by circu- lation of cell atmosphere through the flexible hoses and thimbles. A l-l/2-in.-diam outlet line is provided at the bottom of the reactor vessel for discharging salt to the drain tanks. 2.4.2 Fuel Pump The fuel salt from the reactor flows directly to the centrifugal sump-type pump shown in Fig. 2.3. The pump has a vertical shaft and overhung impeller and operates at & speed of 1160 rpm to deliver 1200 gpm at a discharge head of 49 ft. The pump bowl is about 36 in. in di- amter, and the pump and T5-hp motor assembly is about 8 ft high. Devices are provided in the pump bowl to measure the liquid level as a means of determining the inventory of salt in the system. Small capsules can be lowered into the bowl to take a 10-g sample of salt for analysis or to add 120 g of fuel to the system. About 65 gpm of the pump output is circulated internally to the pump bowl for release of en- trained or dissolved gases from the salt. Helium flows through the gas space in the bowl at a rate of about 200 ft3/&ay (STP) to sweep the highly radioactive xenon and krypton to the off-gas disposal system. The helium also acts as a cover gas to ex- ~ clude air and water vapor. \ n! e t ' UNCLASSIFIED ORNL-LR-DWG-56043-BR A, 5 A ,'\g;;/ égikQ\ A h SHAFT WATER N= J COUPLING COOLED MOTOR l SHAFT SEAL (See Inset) BT e 4 _ == "7 : — T LEAK DETECTOR LUBE OIL IN Y NN ¥ LUBE OIL BREATHER BALL BEARINGS (Face to Face) BEARING HOUSING BALL BEARINGS GAS PURGE IN (Back to Back ) SHAFT SEAL (See Inset) SHIELD COOLANT PASSAGES (In Parallel With Lube Oil) SHIELD PLUG GAS PURGE OUT (See Inset) LUBE OIL OUT SEAL OIL LEAKAGE DRAIN LEAK DETECTOR SAMPLER ENRICHER {Out of Section) (See Inset) BUBBLE TYPE LEVEL INDICATOR GAS FILLED EXPANSION SPACE NON STRIPPER (Spray Ring) SPRAY OPERATING LEVEL To Overflow Tank FIG. 23. MSRE FUEL PUMP €T 14 The pump is equipped with ball bearings that are lubricated and gfij' cooled with oil circulated by an external pumping system. The oil is confined to the bearing housing by mechanical shaft seals. A helium purge enters below the lower seal. A small part of this helijum flows up- ward along the shaft and leaves just below the lower seal, carrying with it any oil vapors that leak through the seal. The remainder flows down- ward along the shaft to the pump bowl and subsequently to the off-gas system. This prevents radioactive gases from reaching the oil. Cooling oil is also circulated through a metal block above the pump bowl which shields the lubricating oil and the pump motor. The motor and the bearing shaft and impeller assembly are remova- ble separately to facilitate maintenance. An overflow tank of 5.5-ft3 volume is installed below the pump to provide sufficient volume for free expansion of salt under all foreseen conditions. 2.4.3 Heat Exchanger Salt discharged by the fuel pump flows through the shell side of the horizontal shell-and-tube heat exchanger shown in Fig. 2.4, where it is cooled from 1225°F to llT5OF. The exchanger is about 16 in. in diameter and 8 ft long and contains one hundred sixty-three l/2-in.-OD U-tubes with an effective surface of 259 ftz. The coolant salt circu- lates through the tubes at a rate of 850 gpm, entering at 1025OF‘and leaving at 1100°F. 2.4.% Coolant Pump The coolant salt is circulated by a centrifugal pump identical in most respects to the fuel pump. The pump has a (5-hp, 1750-rpm motor and delivers 850 gpm against a head of 78 ft. 2.4.5 Radiator The radiator is shown in Fig. 2.5. Seven hundred square feet of cooling surface is provided by 120 tubes 0.75 in. in diameter by 30 ft long. Cooling air is supplied to the radiator by two 250-hp axial blowers with a combined capacity of 200,000 cfm. Salt enters the radi- ator at 1100°F and leaves at 10250F. The temperature rise of the air - is 200°F at design power. To guard against freezing the salt in the ‘EJ , e\ 15 UNCLASSIFIED ORNL-LR-DWG 52036R2 FUEL INLET 1/2-in.-0D TUBES THERMAL-BARRIER PLATE TUBE SHEET COOLANT INLET 16.4-in. OD x 0.2-in. WALL x 8-ft LONG FUEL OUTLET Fig. 2.4. Primaery Heat Exchanger. UNCLASSIFIED ORNL-LR-DWG §5841R2 PENTHOUSE E RADIATOR TUBES COOLANT PUMP 16 F “ww i £ A e llil\fin‘iéwpfid TN WIRE ROPE SHEAVE 4 / Oin) FIRST FLOOR BLDG. 7503 (ELEV. 852 ft - AIR INLET DUCT Radiator Coil and Enclosure. Fig. 2.5. .E*' 17 radiator tubes on suddefiireduction of reactor power, quick-closing doors are provided to shut offhfhe air flow, and the radiator is heated by electrical heaters inside the enclosure. The opening of the doors can be adjusted, and some of the air can be bypassed around the radiator to regulate the heat removal rate. 2.4.6 Drain Tank Systems Four tanks are provided for safe storage of the salt mixtures when they are not in use in the fuel- and coolant-salt circulating systems. Two fuel-salt drain tanks and a flush-salt tank are connected to the reactor by means of the fill and drain line. One drain tank is provided for the coolant salt. A fuel drain tank is shown in Fig. 2.6. The tank is 50 in. in diameter by 86 in. high and has a volume of about 80 ft3, sufficient to hold in a non-critical geometry all the salt that can be contained in the fuel circulating system. The tank is provided with a cooling system capable of removing 100 kw of fission-product decay heat, the cooling being accomplished by boiling water in 32 bayonet tubes that are inserted in thimbles in the tank. The flush-salt tank is similar to the fuel-salt tank except that it has no thimbles or cooling system. New flush salt is like fuel salt but without fissile or fertile material. It is used to wash the fuel circulating system before fuel is added and after fuel is drained, and the only decay heating is by the small quantity of fission products that it removes from the equipment. The coolant-salt tank resembles the flush-salt tank, but it is 40 in. in diameter by 78 in. high and the volume is 50 ft3. The tanks are provided with devices to indicate high and low liquid levels and with weigh cells to indicate the weight of the tanks and their contents. 2.4.7 Piping and Flanges The major components in the salt circulating systems are inter- connected by 5-in. sched-4O piping. Flanged joints between units in the primary system facilitate removal and replacement of components by remotely operated tools. These flanges, called freeze flanges, utilize WATER DOWNCOMER INLETS BAYONET SUPPORT PLATE STRIP WOUND FLEXIBLE HOSE WATER DOWNCOMER GAS PRESSURIZATION AND VENT LINES FUEL SALT SYSTEM FILL AND DRAIN LINE SUPPORT RING BAYONET HEAT EXCHANGER THIMBLES (32) 2. FUEL SALT SYSTEM FILL AND DRAIN LINE Fig. 2.6. INSPECTION, SAMPLER, AND LEVEL PROBE ACGESS TANK FILL LINE Fuel-Salt Drain Tank. UNCLASSIFIED ORNL-LR-DWG 61719 STEAM DROME CORRUGATED FLEXIBLE HOSE STEAM RISER FUEL SALT DRAIN TANK TANK FILL LINE THIMBLE POSITIONING RINGS ~t ] | “i 19 a frozen salt seal between the flange faces as,wéll as a conventional O-ring-type joint to form a helium—buffered, leak-detected type of closure. . | The £ill end drain lines are 1-1/2-in. sched-L4O piping and contain the only "valves" that come in contact with salt. The valves, called freeze valves, have no moving.parts, unmodulated flow control being achieved by freezing or thawing salt in a short, partially flattened section of pipe that can be heated and cooled. 2.4.8 Heaters 'Al] parts of the salt-containing systems are heated electrically to maintain the salts above the liquidus temperature of 84O to 850°F. The equipment is preheated before salt is added and the heaters are energized continuously during reactor operation to make sure that there is no uncontrolled freezing in any of the piping and that the salt can be drained when necessary. The total capacity of the heaters is about 1930 kw, but the actual power consumption is somewhat less than half of this. About 300 kw of heat can be provided by the diesel electric emergency power supply. - 2.4.9 Materials The salt-containing piping and equipment are made of INOR--& special high-nickel and molybdenum.alloy having a good resistance to attack by fuel and coolant salts at temperatures at least as high as 1500°F. The mechanical properties are superior to those of many austen- itic stainless steels, and the alloy is weldable by estab1ished'?ro4' cedures. - The chemical composition and some of the physical properties are given in Table.2.2; Most of‘theVINOR equipment was designed for 1300°F and 50 psig, with an allowable stress of 2750 psi. - Stainless steel piping and valves were used in the helium supply and in the off-gas systems. - 2.4.10 Cover- and Off-Gas Systems A helium cover-gaSVSYSfém prbtécfis fihérbxygen-sénsitive fuel from contact with air or moisture. Commerical helium is suppled in a tank truck and is passed through & purification system to reduce the oxygen and water content below 1 ppm before it is admitted to the reactor. 20 Table 2.2. Composition and Properties of INOR-8 Chemical Properties: Ni 66-71% Mn, max 1.0% Mo 15-18 Si, max 1.0 Cr 6-8 _ Cu, max 0.35 Fe, max 5 B, max 0.010 c 0.04-0.08 W, mex 0.50 Ti + Al, max 0.50 P, max .0.015 S, max 0.02 Co, max 0.20 Physical Properties: Density, 1b/in.> 0.317 Melting point, °F 2470-2555 Thermal conductivity, Btu/hr-fto(F/ft) at 1300°F 12.7 Modulus of elasticity at ~1300°F, psi 24.8 x 106 Specific heat, Btu/lb-°F at 1300°F 0.138 Mean coefficient of thermal expansion, 67 70-1300°F range, in./in.-°F 8.0 x 10 Mechanical Properties: Maximum allowable stress,> psi: at 1000°F 17,000 - 1100°F 13,000 1200°F 6,000 1300°F 3,500 %ASME Boiler and Pressure Vessel Code Case 1315. 21 systems. A flow of 200 ft5/day (STP) is passed continuously through the fuel pump bowl to transport the fission product gases to activated charcoal adsorber beds. The radioactive xenon is retained on the charcoal for a minimum of 90 days, and the krypton for 7-1/2 days, which is sufficient for all but the 85 8 tained well within tolerance, the effluent gas being diluted with 21,000 Kr to decay to insignificant levels. The “Kr is main- cfm of air, filtered, monitored, and dispersed from a 3-ft-diam by 100-ft steel-containment ventilation stack. The cover-gas system is also used to pressurize the drain tanks to move molten salts into the fuel and coolant circulating systems. Gas from these operations is passed through charcoal beds and filters before it is discharged through the off-gas stack. 2.4,11 Instrumentation and Control Systems Nuclear and process control are both important to the operation of the MSRE. The reactor has a negative temperature coefficient of 6.4 to 9.9 x 107 (Ak/k)/oF, depending on the type of fuel that is being used. - The excess reactivity requirements are listed in Table 2.3, and they are not expected to exceed U4 x 1072 Ak/k at the normal operating temper- . ature. The three control rods have a combined worth of 5.6 to 7.6 % Ak/k, depending upon the fuel composition. Their major functions are to elimi- nate the wide temperature varietions that would otherwise accompany changes in power and xenon poison level and to make it possible to hold the reactor suberitical to a temperature 200 to 300°F below the normal operating,temperature. - They have some safety functions, most of which are concerned with the startup of the reactor. Rapid action is not re- quired of the control rods; however, a magnetic clutch is provided in the drive.train to permit the rods to drop into the thimbles with an ac- celeration of 0.5 g as a convenient way of providing insertion rates that are‘more'fapid than the removal rates. Burnup and growth of long- lived fission product poisons'is compensated by adding fuel through the sampler enricher. Complete shutdown of the reactor is accomplished by “draining the fuel. -When the reactor is operated at power levels above a few hundred kilowatts, the power is controlled by regulating the air flow, and 22 Table 2.3. Reactivity Requirements Reactivity, % Nk/k Loss of delayed neutrons by circulating fuel 0.3 Entrained gas 0.2 Power coefficient (from rise in graphite temperature) -0.1 Xenon poisoning (steady state at 10 Mw) —0.7 Samarium-149 transient -0.1 Burnup (120 g of fuel) -0.1 Margin for operation of control rods —0.4 Total -1.9 Uncertainty in estimates (primarily xenon) Total (+)=1.0 to (=)=0.L —2.9 to -1.5 ) 25 thereby the rate of heat removal, at the radiator. The power level is determined by measuring the flow rate and temperature difference in the coolant salt system. . The control rods operate to hold the fuel outlet temperature from the reactor constant, and the inlet temperature is per- mitted to vary with power level. At low power the control rods operate to hold the neutron flux constant, and the heat withdrawal at the radi- ator or the input to the heaters on piping and equipment is adjusted to keep the temperature within a specified range. - Preventing the salts from freezing, except at freeze flanges and vaelves, and protecting the equipment from overheating, are among the most important control functions. Over one thousand thermocouples are installed throughout the fuel and coolant salt systems, and about three- fourths of these serve indication, alarm, or control functions. The heating and cooling equipment is controlled to maintain temperatures ~ (throughout the systems) within specified ranges. Digital computer and data handling equipment are included in the instrumentation to provide rapid compilation and analysis'of the process data. This equipment has no control function but gives current infor- mation about all important variables and warns of abnormal conditions. 2.5 Fuel Processing ‘Batches of fuel or flush salt which have been removed from the reactor circulating system can be processed in separate equipment to per- mit their reuse or to recover the uranium. - Salts that have been contaminated with oxygen to the saturation point (aboutJSQ ppm_dffO2), and thus tend to precipitate the fuel constituents as oxides, can be treated with a hydrogen-hydrogen fluoride gas mixture to femove the oxygenfas water vapbr., These salts can then be reused. A salt batch unacceptably contaminated with fission products, or one in which.itfis:desirable:to_drastically change the uranium content, can be,treatefi.with‘fluorine-gas to separate the uranium from the.carrier salt by vblamilization of UFg. In some instances the carrier salt will be discarded; in others uranium of a different enrichment, thorium, or other constituents will be added to give the desired composition. 24 The processing system consists of a salt storage and processing s tank, supply tanks for the H2, HF, and F2 ature-(75OOF) sodium fluoride adsorber for decontaminating the UF6’ treating gases, a high temper- several low-temperature portable adsorbers for UF6, a. caustic scrubber, and associated piping and instrumentation. All except the UF6 adsorbers are located in the fuel processing cell below the operating floor of Bldg. 7503, as shown in Fig. L.k. . After the uranium has been transferred to the UF6 adsorbers, they are transported to the ORNL Volatility Pilot Plant at X-10, where the UF6 is transferred to product cylinders for return to thefififipjpfbdudtion plants. 2.6 Plant Arrangement The general érrangement of Building 7503 is shown in Fig. 4.3. The main entrance is at the north end. Reactor equipment and major auxil- lary facilities occupy the west half of the building in the high-bay area. The east half of the building contains the control room, offices, change rooms, instrument and general maintenance shops, and storage areas. Additional offices are provided in a separate building to the east of the main building. Equipment for ventilating the operating and experimental areas is located south of the main building. A small cooling tower and small " buildings to house stores and the diesel-electric emergency power equip- ment are located west of the main building. | The reactor primary system and the drain tank system are installed in shielded, pressure-tight reactor and drain tank cells, which occupy most of the south half of the high-bay area. These cells are connected by an open 3-ft-diam duct and are thus both constructed to withstand the same design pressure of 40 psig, with a leakage rate of:less than 1 vol § per day. A vepor-condensing system, buried in the ground south of the building, is provided to keep the pressure below 40 péigfldufing the maximum credible accident by condensing the steam in vapors that are discharged from the reactor cell. When thé reactor is operating, | ‘;;} the reactor and drain tank cells are sealed, purged with nitrogen to o 25 obtain an atmfiephere that is less than 5% oxygen, and maintained at about 2 psi below afmospheric pressure.’ The reactor cell is a carbon steel containment vessel 24 ft in di- ameter and 33 £t in overall height. The top is flat and consists of two layers of removable concrete plugs and beams, fef-a total thickness of 7 £ft. A thin stainless steel membrane is installed between the two layers of plugs and welded to the wall of the steel vessel to provide a tight seal during opefation. ' The reactor cell vessel is located within & 30-ft-diam steel tank. The annular space is‘filled with a magnetite sand and water mixture, and there is‘e minimum of 2 £t of concrete shielding around the outer tenk. In additien to this shielding the reactor vessel is surrounded by & lh-in.-thick steel-and-water thermal shield. - The drain tank cell adjoins the reactor cell on the north. It is a 17-1/2-ft by 21-1/2-ft by 29-ft-high rectangular tank made of rein- forced concrete and lined with stainless steel. The roof structure, in- cluding the membrane, is similar to that of the reactor cell. The coolant cell abuts the reactor cell on the south. It is a ‘shielded area with controlled ventilation but is not sealed. ‘The blowers that supply cooling air to the radiator are installed in an existing blower house along the west wall of the coolant cell. Rooms containing suxiliary and service equipment, instrument trans- mitters, and electrical equipment are located along the east wall of the reactor, drain tank and coolant cells. Ventilation of these rooms is controlled, and some are provided with shielding. The nerth half of the building contains several small shielded cells in which the ventilation is controlled, but which are not gas-tight. These cells are used for storing and processing the fuel, handling and storing liquid wastes, and storing and decentaminating reector equip- ment . | | ) The high-bay area of the buildlng over the cells mentioned sbove is lined with metal, has all but the smaller 0pen1ngs sealed, and is pro- vided with air locks. Ventllatlon is controlled and the area is normally operated at slightly below atmospheric pressure. The effluent air from 26 this area and from all other controlled-ventilation areas is filtered, and monitored before it is discharged to the atmosphere. The contain- ment ventilation equipment consists of a filter pit, two fans, and a 100-ft-high fuel stack. They are located south of the main building and are connected to it by a ventilation duct to the bottom of the re- .actor cell and another along the east side of the high bay. The vent house and charcoal beds for handling the gaseous fission products from the reactor systems are near the southwest corner of the main building. The carbon beds are installed in an existing pit that is filled with water and covered with concrete slabs. The vent house and pit are also controlled-ventilation areas. Gases from the carbon beds are discharged into the ventilation system upstream of the filter. Maintenance of equipment in the fuel circulating and drain tank systems will be by removal of one or more of the concrete roof plugs and use of remote handling and viewing equipment. A heavily shielded maintenance control room with viewing windows is located above‘the operating floor for operation of the cranes and other remotely con- trolled equipment. This room will be used primarily when e large num- ber of the roof plugs are removed and a piece of highly radicactive equipment is to be transferred to a storage cell. Equipment in the coolant cell cannot be approached when the re} actor is operating, but since the induced activity in the coolant salts is short lived, the coolant cell can be entered for direct maintenance shortly after reactor shutdown. 27 3. BSITE The Molten-5alt Reactor Experiment is located in Melton Valley about one-half mile southeast of the main X-10 area of the Oak Ridge National Laboratory, Oak Ridge, Tennessee. The site can be approached from either the northeast or southwest on the asphalt-surfaced 7500 Road. A location map is shown in Fig. 3.1. It may be noted that in the plot plan, Fig. 3.2, and on all con- struction drawings, that the long axis of the building has been taken as the reference, or plant, north. The true north lies about 300 east of this.* The brief descriptive remarks made here regarding the MSRE site are sufficient only to outline some of the factors influencing design of the experiment. The meteorology, climatology, geology, hydrology, seismology, and the general suitability of the location from a safety standpoint are discussed in detail in theéSafgty Analysis Report, Part V, of this report. )7} ' The location is a safe one for construction of reactor equipment, as is evidenced by the several other reactors installed in the area and the fact that the ARE and the 60-Mw(thermal) ART experiments were approved for the same site. The terrain consists of wooded hills and vaileys. The elevation of the MSRE site is about 850 ft above sea level. Haw Ridge, which lies between the MSRE and the main X-10 area, has an average elevation along the top of about 980 ft. The Clinch River (Melton Hill Reservoir) lies two or more miles to the east and south and marks the boundary of the ORNL reservation. The eight or ten square miles included in this bend of the river are also occupied by six other ORNL reactor installations. These are, in most instances, separated from each other by intervening hills and distances of one~half mile or more. The installations include the Tower Shielding Facility, the Health Physics Research Reactor (HPRR), *¥In most instances this report gives compass directions only to in- dicate a general relationship, and the distinction between plant north and true north is not important. In general, unless otherwise stated, the directions given are referred to plant north. Should the reader have need for exact compass bearings, care should be taken to identify the north used in a particular reference or drawing. 28 UNCLASSIFIED ORNL-LR-DWG 4406R TO ORGDP ~5 mile WHITE WING MELTON GATE HILL DAM Fig. 3.1. ORNL Area Map. a’ 29 [~ cooLme WATER jj TOWER x x—I MELTON V:LLEY DRIVE w,,_,a'goo N N [ N T T > == IDIESEL ) ) T SV \ | | 7T X //// f ‘ N-18,800 \x 2 \é_UTILITY . 7] BUILDING . 2 Ve |7 2 x % \ N %/////////////////% x SUPPLY AIR Z / ! FILTER HOUSE 7 / 7 2 ’ \ 2 o t A 7 : e \ DIESEL cfif'sNgRATOR SWITCH 4 | : 2277727277 7 et W4 \ MAINTENANCE % /_4 OFFICE BUILDING/ X CONTROL ROOM / % / \ . | 2 L, // x % T Z \ \ Z/STORES é ?B*l‘_gl\}g%n % L "\ 2222 ///////////’;/;///”///////// A, 1 18.800 ' RN — STAGK Y% X FILTER _vAPOR ’l‘ ) \ CHARCOAL PIT CONDENSING \ BED CELL ] SYSTEM \\- ] N-18,500 \ T . ol \umfi—'*‘*-‘flh“ *”” VENTI-.L—J;(M* VENTILATION YENTH BLOWERS " ////,/””f” FlG. 3.2 PLOT PLAN : MOLTEN SALT REACTOR EXPERIMENT A BUILDING 7503 15400 ~ ’//’ 30 the High-Flux Isotope Reactor (HFIR), and the associated Trans-Uranium Facility (TRUF), the Experimental Gas-Cooled Reactor (EGCR), and the now dismantled Homogeneous Reactor Experiment (HRE-2, or HRT). The direction of the prevailing wind is from the southwest, but close to the ground in Melton Valley during the night, or in stable con- ditions, the wind tends to be from the northeast regardless of the di- rection of the gradient wind. Very strong winds aloft, however, do con- trol the direction and velocity of the valley wind. A frequently en- countered condition is for up-valley light air movement from the south- west during the day followed by a down-valley movement at night.9’lO The soil is largely Conasauge shale, and there are no persistent limestone beds in the area to cause rapid movement of underground water through solution channels or caverns. The shale is relatively imper- meable to water, and such ground flow as might exist is probably limited to a few feet per week. OSurface water has a natural drainage to the south into a small spring-fed tributary of Melton Branch, which in turn, empties into Whiteoak Creek.9’:LO Only one or two very slight earthquakes occur per year in the Tennessee Valley, and it has been judged highly improbable that a major shock will occur in the Oak Ridge area for several thousand years.9’10 The MSRE is supplied with potable water from the X-10 distribution system. The source of the water is the Clinch River. After treatment the water is stored in a T-million-gal reservoir located near the Y-12 Plant. This supply serves the main laboratory complex and also furnishes water to a 16-in. line which makes a complete loop to the south of X-10 to supply the several reactor sites, as shown in Fig. 3.3.¥ Two 1.5- million-gal tanks, with maximum water level of 1055 ft elevation, are located at the top of Haw Ridge as part of this loop system. The MSRE normally receives water through a 12-in. main laid along 7500 Road to the east of the MSRE reactor Building 7503 and joining the 16-in. loop where it crosses the road. An existing 6-in. line along the same road to the west of Bldg. 7503 serves as an alternative supply line. The total available capacity probably exceeds 4000 gpm. Building services . ¥See ORNL Dwg F-46902 for complete layout of the X-10 water supply system. o Unclassified ORNL-IWG 64-8806 a 2 E:Am RESERVOIR o w N :' (e onone l/ - __J([:F/ / L BORATORY AREA/ OAK RIDGE |socnnouous ] CYCLOTRON - BUILDING 7500 a—MELTYON VALLEY ACCESS ROAD MOLTEN SALT REACTOR HEALTH PHYSICS / + RESEARCH REACTOR ACCESS ROAD \k Lo */ SOUTHERN REGIONAL f WASTE DISPOSAL AREA P -——-—-—_ =l , HIGH FLUX ISOTOPE REACTOR - / -/"'é_fl'ncu e * T / [ AEC - TVA FENCE l ¥ \\ . .~ Figure 3.3. Potable Water Supply to MSRE Te 32 and the fire protection system draw directly from the potable supply. Process water also comes from the same supply, but a backflow preventer is installed in the process water line to protect the potable water system. The MSRE is supplied with electric power from the 154-kv TVA system through a substation located Jjust north of the main X-1l0 area, as shown in Fig. 3.4. The 13.8-kv transmission line from the substation to the MSRE (ORNL Circuit 234) skirts the western side of X-10 along First Street. A 13.8-kv feeder line from another 154 to 13.8-kv transformer at the same substation (ORNL Circuit 294 ) passes to the east of X-10 to supply the HFIR area. This line passes close to the MSRE, and the two circuits are connected together through automatic transfer switches on poles at the MSRE so that each can serve as an alternative to the other. The MSRE is normally supplied through Circuit 234. The 13.8-kv, 3-phase, 60-cycle input to the MSRE serves process equipment through a new 1500-kva, 13.8 kv to 480 v, transformer located on the west side of Bldg. 7503. An existing bank of three 250-kva, 13.8 kv to 480 v, transformers on the east side of the building supplies the building lighting, air conditioning, and other general purpose loads. Diesel-driven generators serve as an additional source of emergency power. These were originally installed for the ARE and the ART. There are two 1200-rpm engine-generator sets of 300-kw capacity and one set with a generator name-plate rating of 1200-kw but having a continuous duty, limited by the size of the diesel engine, of 300 kw. The total emergency generating capacity for the MSRE is thus 900 kw. These units, together with the air compressors and compressed air tanks used for starting the large engine and the batteries for starting the two smaller units are housed in a generator house just west of Bldg. T7503. Saturated steam at about 250 psig is supplied to the MSRE through a 6-in. main from the X-10 power plant as shown in Fig. 3.5. There is no condensate return. The chief uses for the steam are building heat and a few distillation processes. Sanitary disposal facilities consist of a septic tank and a drain- age field west of the building. ') v (= SOUTHERN AEGIONAL WASTE DISPOSAL AREA AEC - TVA FENCE — Juaonnonv AREA/ / %)/ eSS Z 2///{{,,, o~ / % 294 138 K- w BUILDING T500 - = MOLTEN SALT REACTOR i._ %fi HIGH FLUX ISOTOPE REACTOR * + MAIN RESERVOIR 5 / JEE%///// 7/ OAK RIDGE ISOCHRONOQUS CYGLOTRON 138KV g RESERVOIR a—MELTON VALLEY ACCESS ROAD ) DRIVE ' + HEALTH PHYSI SICS /fa——— RESEARCH REACTOR ACCESS RO&D YALLEY Louwr .OA' ~— N E LYY P Unclasgsified ORNL-IWG 64-8807 § 181 Kv SUBSTATION § § o ~~ : : ’ W w . . Iz \\; EXPERIME GAS COOLED ¢ Figure 3.%. Electrical Distribution System to MSKE £e Unclassified ORNL IWG 64-8808 v, - i g // SOUTHERN REGIONAL WASTE DISPOSAL AREA ‘_’__._—l————_ 7 /// , / E//// O EEm ] \ /— r m‘\l . X 7\ \\n C-TVvA FENCE / i (‘;ETH!L CHURCH e 7 a—MUELTOR YALLEY ACCESS ROAD VALLEY MOLTEN SALT REACTOR HEALYH PHYSICS RESEARCH REACTOR ACCESS ROAD I HIGH FLUX 1S0TOPE REACTOR L 1 / L[N / & > < Nm—ITm k. Ty < » - Figure 3.5. Steem Supply to MSRE e 35 4, PLANT 4.1 General General views of Bldg. 7503 are shown in Figs. 4.1 and 4.2, Sincé some of the building spaces serve no functions which are clearly related to the requirements of the MSRE, attention is again called to the fact that the 7503 Area was originally constructed for the ARE and later modified for the ART. It was not occupied between cancellation of the ART in 1957 and the present usage. Although some accommodations in the MSRE design were necessary to fit the experiment into the existing structures, considerable savings in time and expense were gained by their use. Office, control room, shop and washroom spaces could be used almost without change, and the heat rejection equipment, which included axial blowers, ducting and stack, were a valuable asset. The existing con- tainment vessel height was increased by about 8-1/2 ft, and the shield- ing walls, roof plugs, cell Wail penetrations, supports, and other structural features were extensively modified. Considerable excavation was needed within the high bay to make room for the drain tank cell. In modifying the existing buildings for the MSRE, the areas were divided into five classifications (see Ref. 11 for detailed description): Class I. These areas have high radiation levels at all times once the reactor has operated at power and highly radiocactive fuel or Wastés have been handled in the equipment. They include the reactor céll,‘drain tank cell; fuel prbcessing cell, liquid waste cell, charcoal bed pit, etc. The equipment in these areas must withstand relatively - high radiation levels and in most:cases must be maintalned by remote maintenance methods. Direct maintenance will be possible in the fuel processing3and 1iquid’waste cells,,but the equipment must first be decontaminated. - Clasé'II;- Areas in this classification are not accessible when _fuel sa1t'is in the primary circulating system but can be entered with- in a short time after the salt has been drained. The coolant salt area, vhich includes the radiator, coolant pump, and coolant-salt drain tank, are in this category. The west tunnel and the unshielded areas of the Pig. 4.1. Front View of Building 7503. { Unclassified Photo 66849 9¢ o Fig.. 4.2. Rear View Building 7503 During MSRE Construction. Unclassified Photo 663986 LE 38 blower house are other examples. Equipment in these areas can be re- paired by direct approach. Class III. These are areas that are accessible during periods of low-power operation of the reactor, such as the special equipment room and south electric service area, but cannot be entered if the power is above 1 Mw., The equipment in these areas can he inspected and repaired without draining the reaétor. Class IV. These are areas that are accessible or habitable at all times except under the conditions described in Class V, below. These areas include office spaces, control rooms, etc. Class V. The maintenance control room will be the only habifiable areas during maintenance operations when large, radioactive components are being removed from the reactor cell. The rest of the MSRE site must be evacuated. This shielded room contains remote control units for the cranes and TV cameras. L,2 Offices Offices for the operational personnel are located in Bldg. 7503 (see Section 4.3). Administrative and supporting personnel are located in Bldg. 7509, which adjoins Bldg. 7503 on the east side. Bldg. 7509 is a new one-story, 43-ft x 87-ft concrete-block building equipped with central air conditioning. The main entrance for visitors to the MSRE is at the east end of this building. 4.3 Building Above grade, Building 7503 is constructed of steel framing and asbestos cement type of corrugated siding with a sheet metal interior finish., Reinforced concrete is used in almost all cases below the 850-ft elevation. Floor plans at the 852- and 840-ft levels are shown in Figs. 4.3 and 4.4, The general location of equipment is also shown in Fig; 4.3, An elevation view is shown in Fig. 4.5, The west half of the building above the 852-ft elevation is about 42 £t wide, 157 ft long, and 33 ft high. This high, or crane, bay area houses the reactor cell, drain tank cell, coolant salt penthouse, and most of the auxiliary cells (see Section 4.3.9). UNCLASSIFIED ORNL-DWG 64-8726 BUILDING 7509 (OFFICES) 7 INSTRUMENT STORE ROOM OFFICE OFFICE OFFICE OFFICE INSTRUMENT SHOP CHANGE OFFICE ROOM NUCLEAR SHAFT AUXILIA CONTROL ROOM MAIN ; \ CONTROL / DATA ROOM ROOM ) HOT SAM - CHANGE ROO ENRICHE EQUIP STORAGE R . PRACTICE CELL LIQUID LL REMOTE MAINT. CONTROL ROOM DECONTAMINATION CELL EL PROCESSING CELL Fig. 4.3. Plan at 852-ft Elevation. 6¢ UNCLASSIFIED ORNL DWG. 863-4347 9 E - OFFICE FUEL PUMP BATTERY ROOM LUBE OIL MAINTENANCE SHOP CHEMICAL SERVICE LABORATORY TUNNE PUNP OIL SYSTEM D 10 FILTERS AND STACK CELL VENTILATION AND BLOCK VALVE ¢ SPECIAL ||TRANS EQUIP. ROOM 0 £Q STORAGE TO VAPOR MAINTENANCE PRATICE CELL CELL :: HEAT sv:;::‘: B COOLANT SALT 1QUID WASTE DRAIN TANK CELL FUEL SALY FUEL SALT ADDITI AT) FUEL FLUSH TANK DRAIN NO, 2 TANK FUEL DRAIN TANK NO. 1 gHERMAL BLOWERS HIELD REACTOR CELL ANNULUS BLOWER ®ELEC. SERVICE AREA BELOW HOUSE RADIATOR BLOWERS Fig. 4.4. Plan at 840-ft Elevation. s ! { O% UNCLASSIFIED ORNL DWG. 64-597 3 AND #O-TON /%~ CRANES —-——== COOLANT SALT PUMP REACTCR CELL FUEL SALT ANNULUS SHIELD LIQUIL WASTE CELL +]DECONTAMINATION DRAIN TANK CELL RADIATOR BYPASS Duct PROC COOLANT SALT DRAIN TANK ACTOR VESSEL THERMAL SHIELD DRAIN LINE FUEL DRAIN TANK NO. 2 Fig. 4.5. Elevation Building 7503. 9 42 The eastern half of the building above the 852-ft elevation is 38 ft wide, 157 ft long, and about 12 ft high. Offices for operational personnel are located along the east wall of the north end. The main control room, auxiliary control room, and a room used for the logger, computer, and for the shift supervisor on duty are located across the hall on the western side. The large hall provides ample space for an observation gallery. Windows behind the control panel enable the operating personnel to view the top of the reactor cell and other operating areas of the high bay. The change rooms are located near the center of the building. The southeastern corner is used for an instrument shop, instrument stores and offices for instrument depart- ment supervisory personnel. Most of the western half of the building at the 840 level is occupied by the reactor cell, drain tank cell, and auxiliary cells. The emergency nitrogen-cylinder station is located against the west wall in the northwest corner of this level. Switch boxes used in the heater circuits are located across the aisle between columns A and C (see Fig. 4.3). Behind these switch boxes is an 8-ft x LO-1/2-ft pit with a floor elevation of 831-1/2 ft. This pit contains heater circuit induction regulators with some heater transformers mounted above. It is accessible from the 840-ft level by stairs located at the east end. Additional induction regulators and rheostats are located at column line C between columns 2 and 3. The heater control panels and thermocouple scanner panels are located along column line C between columns 3 and L. The batteries for the 48- and 250-volt DC emergency power supply are in an 18-ft x 18-ft battery room in the northeast corner. The motor generators and control panels for the 48-v system are in an area west of the battery room. The main valves and controls for the fire pro- tection sprinkler system are installed along the north wall. A maintenance shop area is provided between columns 2 and 4. The process water backflow preventer is installed on the east wall between columns 2 and 3. The area between column lines 4 and 6 houses the main lighting breakers, switch boxes and transformers, the intercom control panel, . G 43 water heater and air conditioners for the main control room and transmitter room, as well as & lunch room and meeting room for main- tenance personnel. The transmitter room located between column lines 5 and 6 is described in Section 4.3.7. The service room, a 16-ft by 27-ft room, located at the northeast corner of the 840-ft level, serves as a small chemistry laboratory and access to the service tunnel (Section 4.3.6). The instrument panels for the fuel and coolant lube oil systems are located in this area. 4.3.1 Reactor Cell _ | The reactor cell, shown in Fig. 4.9, is a cylindrical carbon steel vessel 24 ft in dlameter and 33 ft in overall height (extending from the 819 to 852-ft elevation), with a hemispherical bottom and a flat top. The lower 24-1/2 £t (819 to 843-1/2-ft elevation) was built for the ART in 1956, It was designed for 195 psig at 565°F and was tested hydro- statically at 300 psig.12 The hemispherical bottom is 1 to 1-1/L in, thick., The cylindrical portion is 2 in. thick except for the section that contains the large penetrations, where it is 4 in. thick. This vessel was modified for the MSRE in 1962 by lenghtening the cylindrical section 8-1/2 ft (843-1/2 to 852-ft elevation). Several new penetrations were instelled, and a 12-in. section of 8-in. sched-80 pipe closed by a pipe cap was welded into the bottom of the vessel to form a sump. The extension to the vessel was 2 in. thick except for the top section, which was made as a 7-1/k-in. by 1lh-in. flange for bolting the top shield beams in place. The flange and top shield structure were designed for 40 psig, measured at the top of the cell. Both the - original vessel and the extension were made of ASTM A20l, Grade B, fire- box quality gteel. Material for the extension was purchased to speci- fication ASTM A300 to obtain steel with good impact properties at low temperatfire. Steel for the original vessel was purchased to specifi- cation ASTM A201. : , All the welds on the reactor cell vessel were inspected by mag- netic particle methods if ‘they were in carbon steel, or by liquid penetrant methods if they were in stainless steel. All butt welds and penetration welds were radiographed. After all the welding was completed, - the vessel was stress relieved by heating to 1150 to 1200°F for 7~l/2 hr. 4y Calculated stresses in the vessel were well below those permitted by ASME Boiler and Pressure Vessel Code Case 1272N-3.(u9) Allowable stresses for ASTM A-201 Grade B steel were taken és 16,500 psi for general membrane stresses, 24,750 for general membrane plus-general bending plus local membrane stresses, and 45,000 psi forfcémbined primary and secondary stresses.(l5) The top of the cell is constructed of two layers of 3-1/2-ftwthick, reinforced concrete blocks, with a stalnless steel membranerbetween, as shown in Figure 4.6. The top layer is ordinary concrete with a density of 150 lb/ft5, and the bottom layer is magnetite concrete with a density of 220 1b/ft5. Blocks in both layers run east and west. To aid in remote maintenance, the bottom layer is divided into three rows of | blocks. Blocks in the outer rows are supported on one end by a 1l3-in. by b-in.-channel iron ring welded to the inside of the cell wall. The cavity in the channel is filled with steel shot to provide shielding for . the:-cracks betwken edges of the blocks and the cell wall. One-half-inch steel plate stiffeners are installed at 9° intervals. The top of the channel is at the 848-1/2-ft elevation. | Two beams provide the rest of the support for the bottom layer of blocks. These beams were built of 36-in. WF 150-1b I-beams with angle iron and steel plate stiffeners. The cavities were filled with con- crete for shielding. The beams rest on a built-up support.plant assembly, which is welded to the side of the cell at the 847-ft~7-in. elevation. Offsets 6-1/L-in. by 26 in, are provided in the ends of the bottom blocks to fit over the support beams. Guides formed by angle iron assure proper alignment. Several of the bottom blocks have stepped plugs for access to selected parts of the cell for remote maintenance. These are described in Part X. The sides of the blocks are recessed 1/2 in. for ih in, down from the top. With blocks set side by side and with a 1/2-in. gap between, a 1-1/2-in. slot is formed at the top. One-inch-thick steel plate 12 in. high is placed in the slots for shielding. The ll-gage, ASTM-A2LO 304 stainless steel membrane is placed on top of the bottom layer of blocks and is seal-welded to the sides of the cell. Cover plates are provided over each access plug. These are bolted to the membrane and are sealed 45 ORNL DWG, 64598 —~— - ) e olo olo \ O‘E"J __-u.?___c.) T 1T TN i =k N —\ N N\ P& / / frtme e, 4 D4 w~ N o’ o —— - — -.\, s N \ ] \ : \ O\N\L JI//////O TR Z%|° NG et L= | S s = .fl-é—-—o o g/ ™~ ) PLAN ES‘L%DOWN ',RONE‘ \-SUPPORT BEAM ACCESS SHIELDING PLUGS " INSERT SHIELDING ELL WALL SECTION "XX" ANNULUS Fig. 4.6. Shield Block Arrangement at Top of Reactor Cell. 46 by neoprene O-rings. A l/8-in. layer of masonite is placed on top of \EJ the membrane to protect it from damage by the top layer of blocks. The top blocks are beams that reach from one side of the cell to the other. The ends of these blocks are bolted to the top ring of the cell by use of fifty 2-1/2-in. No. U NC-2 studs, 57-1/% in. long, made from ASTM-A320, Grade L7, bolting steel. These studs pass through holes that were formed by casting 3-in. sched-40 pipes in the ends of the blocks., Cold-rolled steel washers, 9 in. by 9 in. by 1 in. thick, and standard 2-1/2-in. No. 4 NC-2 nuts are used on each stud. " A removable structural steel platform (elevation 823-1/2 ft at top) forms a floor in the reactor cell vessel and a base for supporting ma jor pieces of equipment. The reactor cell vessel is installed in another cylindrical steel tank that is referred to here as the shield tank. This tank is 30 ft in diameter by 35-1/2 ft high (elevation 816-1/2 to 852 ft). The flat bottom is 3/L in. thick, and the cylindrical section is 3/8 in. thick. The shield tank sits on a reinforced concrete foundation that is 34-1/2 ft in diameter by 2-1/2 ft thick. The reactor vessel cell is centered in the shield tank and supported by a 15-ft-diam by 5-ft- high cylindrical skirt made on l-in.-thick steel plate reinforced by appropriate rings and stiffeners. The skirt is Jjoined to the hemispheri- cal bottom of the reactor cell in a manner that provides for some flexi- bility and differential expansion and is anchored to the concrete foundation with eighteen 2-in.-diam bolts. From elevation 816-1/2 to 846 ft, the annulus between the shield tank and the reactor cell vessel and skirt is filled with magnetite ~: sand and water for shielding. The water contains about 200 ppm of a chromate-type rust inhibitor, Nalco-360. A L-in.-diam overflow line to the coolant cell controls the water level in the annulus. The region beneath the reactor cell vessel inside the skirt con- tains only water, and steam will be produced there if a large quantity of salt is spilled into the bottom of the reactor cell. An 8-in.-diam vent pipe is provided to permit the steam to escape at low pressure.(lu) This pipe connects into the skirt at the Jjunction with the reactor cell _ and extends to elevation 846 ft where it passes through the wall of o the shield tank and terminates as an open pipe in the coolant cell. - 47 From elevation 846 to 852 ft, the annulus between the reactor cell and shield tank is filled with a ring of magnetite concrete. The con- crete ring improves the shielding at the operating floor level and provides some stiffening for the top of the reactor cell vessel. The concrete ring is supported off the wall of the shield tank, and the reactor cell wall is free to move through the ring and to expand and contract relative to‘the'shield tank. Numérous penetrations are required through the walle of the reactor cell and shield.tank to provide for process and service piping, electrical and instrument leads, and for other accesses. The penetrations are L- to 36-in.-diam pipe sleevés welded into the walls of the reactor cell and the shield tank. Since the reactor cell will be near 150°F when the reactor is operating, and the temperature of the shield tank may at times be as low as 60°F, bellows weré incorporated in most of the sleeves to permit rfidial and axial movement of one tank reiative to the. other without producingfiekcessivéwstress;- The bellows are covered with partial sleéves to prevent the.sand'from packing tightly'around them. - | e Several other lines are installed in the penetrations diré¢tiy o with welded seals at one or both ends, or they are grouped in plugs which are filled with concrete and inserted in the penetrations. The major openings are the 36-in.-diam neutron instrument tube and drain tank interconnection and the 3%0-in.-diam duct for ventilating the cell whenlmaintenance is in progress. The original tank contained several other 8-in.-and 24-in,-dlam penetrations, and they were either removed or closed and filled with shielding. The penetfations, their sizes and functions are listed in Table L.l. 4,%,2 Drain Tank Cell The drain tank cell shown in Fig. 4.3 is 17 £t, 7 in. by 21 ft, 2-1/2 in.,'with the corners beveled at 45° angles for 2-1/2 ft. The flat floor is at the 81hk-ft elevation, and the stainless steel membrane between the two layers of top blocks is at the 838-ft-6-in. elevation. The open pit extends to the 852-ft elevation. The cell was designed for 40 psig and when completed in 1962, it was hydrostatically tested at 48 psig (measured at the elevation of the membrane at 838-1/2 f£t). ,.,..-..,,.. R ot e e g Table 4.1. Reactor Cell Penetrations MSRE Approximate Location Reactor Cell in the Reactor Cell - Penetration | Pefifiiiiiion gflfifi:i Identification El?gzgion (N = d%tgef.) Access Area Si?i£.§D Shield;: X R-L Reactor Leak Detectors 836 15 S. Elec. Serv. Area 24 Magnetite grout CII "R-3 Electrical 83k 30 S. Elec. Serv. Area 2k Magnetite grout III R-2 Electrical 836 L5 S. Elec., Serv. Area 2L Magnetite grout IV R-1 Thermbcofiples 834 60 S. Elec., Serv. Area 2L ‘Magnetite/grout ’V_ R Instrumentation 836 5 S. Elec. Serv. Area | 2k Magnetite grout VI | Sampler Offgas (918, 542) 87 110 High Bay I Fuel Sampler VII Sampler (999) | 847 115 High Bay 6 Steel plates VIII S-1 FP (590, 703, TOk, TO6) 836-9" 125 Service Tunnel 18 Sand and weter from anm X Neutron Instrument Tube 834 -5" 145 High Bay 36 Water in penetration X o FP Level (592, 593, 596) 8Ll 6" 155 SER L ‘Tube filled with magnet: XT 8-3 FP (516, 519, 524, 606) 836-9" 160 SER 18 Tube filled with sand a XTI -4 Component Coolant Air (91T) 829-10" 165 SER 6 Lead in anmulus XIII | Coolant Salt to HX (200) 840-10" 170 Coolaent Cell 2k Steel except for pipe a pany Water Lines (830, 831) 839-9" 185 Coolant Cell 8 Steel shot except for si XV " Spere 839-9" 200 Coolant Cell 8 . Steel shot except for si XVI | Water Lines (8, 845) 839-9" 205 Coolant Cell 8 Steel shot except for st XVIX Water Lines (838, 846) 839-9" 210 Coolant Cell 8 Steel shot except for si XVIIT Water Lines (840, 84l) 839-9" 220 Coolant Cell 8 Steel shot except for st XIx Coolant Salt to Radiator (201) 837 220 Coolant Cell 24 Steel except for pipe‘az XX offgas (522) 839-9" 225 Coolant Cell. 6 Steel shot except for s XXT ortgas (561) 839-9" 230 Coolant Cell 6 Steel shot except for s XXII ' Cell Exhaust Duct (930) 824-10" 2l5 CDT Cell 30 Steel plate in reactor ¢ XXITT R-T Thermocouple 836 325 West Tunnel 2k Magnetite grout XTIV Drain Tank Cell Inter- 825.2" 330 Drain Tank Cell 36 None needed connection (103, 333, 521, 561, 920) 48 Reference Drawings g (General References: EGGD-4OTO4, 41487, 41489, 41k9o) DKKD-40976, EBBD-41863, EBBD-41864, DIJD-5549L, DIJD-4O4S5 DKKD~40976, EBBD-41863, EBBD-4186L, EMMZ-56230, EMMZ-56246 DKKD-40976, EBED-41863, EBBD-41864, EMMZ-56230, EMMZ-56246 DKKD-40976, EBBD-41863, EBBD-41864, DHHB-55567 DKKD-49976, EBBD~41863, EBBD-41864, DHHB-55567 DKKD-40973, DKKD-LO9Th DKKD-409T3, DKKD-4O9T4, DBBC-U1339 lus DKKD-4OT1T, EKKD=-40T35 DKKD-4OT16, EKKD-4OT15, EHHA-41796 te grout DKKD-409T3, DKKD-409T5, BGGD-55411, EJID-55428 1 water from annulus DKKD-4OT18, EKKD-LOT3T, EGGD-55411 . DKKD-4OT14, EGGD-55411 i heaters EKKD-4OT11, EGGZ-55498 raight~through pipes DKKD-4OTLO, DKKD-4OTL1 raight-through pipes DKKD-4OT4EO, DKKD-LOTLL raight-through pipes DKKD-4OTHO, DKKD-4OTLL raight-through pipes DKKD-40T40, DKKD-4OT4L raight-through pipes DKKD-4OT4O, DKKD-4OT4L 1 heaters DKKD-40T12, EGGZ-55498 ralght~-through pipes DKKD~-40T40, DKKD-4OTUL raight-through pipes DKKD-4OTUO, DKKD-4OTHL 211 DKKD-40T10, EKKD-LOTAS DKKD-40976, EBBD-41863, EBED-4186Y4, DHHB-5556T EKKD-40T13 49 The bottom and sides have a 3/16-in.-thick stainless steel liner backed up by heavily reinforced concrete, magnetite concrete being used vhere required for biological shielding. The liner is welded to an angle-iron grid work at approximately 8-in. spacing, with 1/2-in. plug welds. The angle irons are welded to reinforcement rods embedded in the concrete. Vertical columns ifi the north and south walls are welded to horizontal beams embedded in the concrete of the cell floor, The tops of the columns are welded to horizontal 36-in. WF 160 I-beams at elevation 842 £t 1 in. to 842 £t 4-3/8 in. by welding a 1-1/kL-in, plate to the web of the beam. Eighty-two 3-1/k-in. by 4-1/2-in. by 10-in. steel keys are wedged into this slot to hold down the top blocks. The top of the cell is constructed using two layers of reinforced concrete blocks with an 1l-gauge (A-204, 304 stainless steel) membrane between. Both layers of blocks are ordinary concrete (density 150 1b/ft3). The bottom layer is 4 ft thick and the top layer is 3-1/2 ft thick. | The block arrangement shown in Fig. 4.7 was selected to facilitate remote maintenance. One side of the lower blocks, which run east and west, is supported by a ledge at an elevation of 834-1/2 ft. The other side of these and the ends of the north-south blocks are sup- ported by beams that extend from the east to the west side of the cell. These beams are built up of 2k-in., 105.9-1b I-beams with angle iron and steel plate stiffeners. 'The cavities are poured full of concrete for shielding. These rest on a built-up support plate assembly, which is welded to the side of the sfainless steel liner and is anchored ~into the concrete walls. Offsets, h—l/h in. by 25-1/2 in., are pro- -vided in'the ends of the bottom blocks to fit over the support beams. "Vfi grooves formed by angle‘irons assure proper alignment. The sides of fihe,botfom blocks are recessed 1/2 in. for 14 in. down from the top. With two blocks side by side, with a 1/2-in. gap between the sides at the bottom, a 1-1/2-in. slot is formed at the top. One-inch steel plates, lBQin. high are put into the slots to provide biological shielding. 50 ORNL-IWNG 64-8809 Unclassified > . _ I TImes Ao L o [v3] Q o wd W o x AT Tt T 13 — \\ e et e \\nl. e A .I.II.I.VMJ \.III'-*[T]]!III —— e v | S— — - j m 0 h N w - < M~ - __ln.lv - N N ~N - < o 0N W N 0 © - -— n N N N —_—te o L e — — ) ] -] e II.I.IJI-II.' Jllll. it e e et IlllJ.llIl.l.l - ¥ » o " © o0 o O 3 Y N A A== N ot e e et Y e L L L/ / lllll 8¢l | | gel | 1 0] ~/ 0N " -r-“»hr ._"L..L.::-L. llx xfl PLAN KEYS e o O= a< >l wno = x x s N £Loxr odal &3 K — L — ‘V." . a2t a8y 42 - ;f‘“‘“. SUTUIE FREELE FLANGE 26" t | . o' O » Y —a “f f 9 1‘ A b fi & i H v 3 ¥ ¥ ) b Unclassified ORNL DWG 64-8811 -; £ . 5 i s t 4, et L : Yorw Seieo i i """ o \h —GRAEWTE SATPLER STANDE P WS & h et .ot — SPace cooLee | — 0 sene5d ot se0-8 = . § favaaaTon F3I T e i s o Y WV Al » T R e R i T e e LT Y et . G 66 5.2 Flowsheet | | * A detailed process flowsheet of the fuel circulating system is shown in Fig. 5.3 (ORNL Dwg. AA-A-MOSBO).15 An explanation of the symbols used on the flowsheet is given in the Appendix. The data sheets,16 the 17 ‘ line séhedule, and the instrument application dlagrams supply the supplemental information needed for detailed study of the flowsheet. Thermocouple information is tabulated on ORNL Dwg. A-AA-B-40511 (51 sheets). _ In the following discussion of the process flowsheet shown in Fig. 5.3, detailed.descriptions of the reactor, heat exchanger, and pump are re- v gerved for Secs. 5.3, 5.4, and 5.5. The instrumentation and controls are mentioned in this secfion only to the extent necessary to explain the flowsheet. A detailed description of the instrumentation, including - the interlocking controls, etc., is given in Part II. During operation of the reactor, fuel salt is circulated through the fuel system at a rate of 1200 gpm. The base pressure in the system is 5 psig-wthe pressure of the helium cover gas at the surface of the salt in the pump bowl. At design conditions of 10 Mw power level, fuel enters the reactor at 1175°F and 35 psig, flows through the reactor vessel‘ and the reactor core, and leaves at 1225°F and 7 psig. It flows through line 100 to the suction of the fuel pump and is discharged by the pump through line 101 to the heat exchanger. The fuel enters the shell side of the heat exchanger at 1225°F and 55 psig and leaves at 1175°F and v 355 bsig. Coolant salt is circulated through the tubes, entering at 1025°F and T7 psig and leaving at 1100°F and 47 psig. Fuel from the heat ex- changer'is returned to the reactor vessel through line 102. The pipe lines in the circulating system are all 5-in. sched-4O INOR-8 pipe, and the flow velocity is about 20 ft/sec. The total volume of salt in piping and primary circulating system equipment under normal operating conditions is about 73 ft5. Line 10% is provided to drain the contents of the fuel salt through freeze valve 103 into the fuel drain tank system. An overflow tank under the pump bowl, and connected to the bowl through line 520, provides 5.5 f’p3 of additional volume for expansion of salt and for protection against J 10 ENRICHER SAMPLER RE VISIONS - ' i..(..c/c,_g) on SEE DCN 2491 SEE DCH 2681 COOLANT PUMP MOTOR T SEE DCN FUEL TS SamE——— ' PUMP I O%CL'IAL . MOTOR :cc)— - : . EAEE R SIS S '\ eo- ‘ l_senwcs Sira ' : I / | I TUNNEL SEE DWE. D-AAA-40008 -8 1CC/Dav orL SPECIAL ROOM 8 PSIG FUEL PUMP 7C OFF (F SYSTEM TRANSMITTER ROOM DRAIN /] ‘_\ | O DRAIN SYSTEM I FREEZE ST S LR REVNONS COMPONENT COOLING SYSTEM COMPONENT mOLING FUMP DATA 00T N ;-40-8 |.! 40 s_j ?25-78 SeEnee— SE— DRAIN "?ANK CELL I 1O FUEL DRAIN TANK SYSTEM 6 FLANGE PAS WITH 4 REMOTE L EAK DETECTOR LINES ON Tw TO THERMAL SHIELD AUTO-RESISTANCE HEATING | UG __l& =t EAX DETECTOR SERVES 2 FLANGES THROUGH CONNECTING J- TURING Eq—-REMOTE GAS LINE MISCONNECT —-F‘QIG — Nomm. L/ HEAT EX {(HXx) REACTOR CELL | | | ‘ _ AT . | coouxml THIS DRAWING REFL AS BUILT CHANGES ‘ . r— ' ‘ CELL FUTURE FLANGES - : _ FF-200 & ' ' o : 1025°F MCLTEN SALT FEACTOR EXPERIMENT FUEL SYSTEM PRCCESS FLOW - SHEET OAK RIDGE NATIONAL LASORATORY UNION. CARBIDE NUGLEAR ComPaNY 13143 e | D-aA-2-40880 FIGURE 5.3 68 overfilling of the system. The drain and overflow lines are 1-1/2-in. & sched-40 INOR-8 pipe. The reactor‘vessel is installed in a stainless steel thermal shield that supports the reactor vessel and forms the outer wall of the reactor furnace. The thermal shield is 16 in. thick and contains about 50% steel and 50% water, which absorbs most of the neutron and gamma ray leakage from the reactor. Water circulates through the shield at a rate of 100 gpm and removes 180 kw of heat. It enters through line 844 and leaves through line 845, with an estimated maximum temperature rise of 12°F. The treated wéter supply is described in Sec. 15. A nmuclear instrument thimble penetrates the wall of the reactor cell vessel, the outer wall of the thermal shield, and terminates at the inner wall. This:thimble is filled with water and contains two compensated.ion chambers, two fission chambers, and three safety chambers for monitoring | the nuclear performance of the reactor. u o The inside of the thermal shield is lined with 6 in. of high tempera- ture insulation, and the annulus between the reactor vessel and the in- sulation contains 126 vertical tubular heaters. The heaters are divided | between three circuits with a total capacity of 60 kw. - | Temperatures are monitored at 48 locations on the reactor vessel and ‘ top head assembly, most of which have spares, giving a total of 80 thermo- couples (see ORNL Dwg. D-HH-B h0528). Temperatures at 25 of these locations are scanned continuously and are used as & gulde to_control the operation - of the heaters. " A flanged nozzle on the top of the reactor vessel passes through the top of the thermal shield and provides access to the core for the control - rod thimbles and for insertion of graphite and metal specimens for irradi- atidn. The access nozzle and plug are cooled by gas to provide frozen salt seals in the annulus between them and in the sample port annulus. ' Gas coolant is supplied through lines 961, 962, and 96% at a rate of 10 ~ scfm through each and is discharged directly to the cell atmosphere. Gas coolant for the three control rods is supplied at a rate of 15 scfm through line 915 and is discharged to the cell atmosphere through line 956. Va.lves are provided in the inlet and outlet lines to block the flow and o prevent fuel salt from being discharged into the cell if a thimble il develops a leak. 1 69 The system for circulating the cooling gas, which 1s.>95% nitrogen and <5% oxygen (and is also the atmosphere in the reactor and drain tank cells), is described in Sec. 16, _ The sample port in the access nozzle opens into the graphite sampler housing. This is & steel tank in which the atmosphere can be controlled to prevent the reactor and the samples from being contaminated by oxygen and moisture as the samples are transferred into and out of the core. The transfer must be done with the reactor shut down and drained. Line 918 ventilates the sampler housing to the reactor offgas system. Dry helium or nitrogen is supplied to the housing through the seals on the cover. _ Line 100 connects the outlet of the reactor vessel to the suction of the fuel pump. Thermocouples near the entrance to line 100 are used for alarm and control circuits and to sense the reactor outlet temperature, which is recorded and logged on the data logger. Line 100 has & ffeeze flange joint (FF-100). The buffer zone of the ring joint seal is supplied with helium and monitored for leakage through line 410. Three pairs of thermocouples are installed on the flanges with one thermocouple of each palr serving as a spare. Thermocouples at two locations are connected to temperature switches to annunciate an alarm if the temperature falls below & preset value (see Instrument Application Diagram, Part II, or ORNL Dwg. D-AA-B-40500). The leak detector and thermocouple installations on FF-100 are duplicated on all other freeze flanges in the reactor system. A pipeline heater of k-kw capacity and a spare are installed between the reactor vessel and FF-100. A similar heater of h4-kw capacity is installed on the horizontal section of the pipe between FF-100 and the pump bowl. The vertical éection'of.pipe beneath the‘pump bowl is in the pump furnace. The pipeline heaters, described in detail in Sec. 5.6.k, are small furnaces that are assenbled from ceramic heaters and reflective insulation and are made to be easily removable for maintenance. Thermo- couples are attached to the pipe under each heater unit to monitor the temperature and are used as a gulde to control the heaters. The fuel pump is a vertical sump-type pump that circulates 1200 gpnm of salt against a head of 49 ft when operated at a speed of 1150 rpm. 70 About 65 gpm is recirculated internslly into the pump bowl, 15 gpm along the shaft and 50 gpm in a spray into the gas space, for removing krypton and xenon. The liquid level in the pump bowl is determined by means of two bubblers. Helium is introduced near the bottom of the pump bowl through lines 593 and 596. Line 592 is a reference line that connects to the expansion volume in the pump bowl near the top and is purged with. helium to prevent back diffusion of radiocactive gases. Signals from the level indicators are monitored continuously, logged on the data logger, and used for alarm and control circuits. The main purge of helium through the pump bowl enters through line 516 just below the lower shaft seal in the beafing housing. Most of the gas flows downward through the labyrinth between the shaft and the shield block in the neck of the bowl to prevent large amounts of radiocactive gas from reaching the seal. This helium combines with the helium from the bubblers and carries the radioactive gases out of the pump house through line 522. Line 522 is enlarged from 1/2-in. pipe to 4-in. pipe to provide a holdup volume of 6 £t and one hour of delay for the decay of the short-lived radiocactive isotopes before the gas leaves the reactor cell and enters the offgas disposal system. The helium supply system is described in Sec. 10.4. The offgas system is described in Sec. 12. The distribution of helium to the pump is listed in Table 5.1, below. Table 5.1. Distribution of Helium Supply to Fuel Pump Pump bowl bubblers Line 593 0.37 liter/min Line 596 0.37 liter/min 1300 liter/day Line 592 0.15 liter/min Pump bowl purge - Line 516 Down shaft annulus 2.3 liter/min 3400 liter/day Oout line 524 0.1 liter/min Overflow tank bubblers Line 599 0.37 liter/min | Line 600 0.37 liter/min 1300 liter/day Line 589 0.15 liter/min Total 6000 liter/day Th > o 71 Line 521 connects the pump offgas line to the gas lines in the drain tank system to equalize the gas pressures in the drain tanks during normal operation and facilitate the transfer of gas between systems during a reactor drain. A small amount of.helium that enters the pump bowl through line 516 flows upward through the labyrinth, combines with a small amount of oil that leaks through the lower shaft seal, and the mixture passes out of the reactor cell through the lead-shielded (1—1/2) line 52% to the oil catch tank located in the special equipment room. After leaving the oil catch tank, the gas flows on to the offgas system through line 524, which is fitted with a pressure reducing capillary, a filter, and a flow indi- cating instrument. Signals from this instrument initiate an alarm if the flow is outside a specified range. The maximum height of the liquid level in the pump bowl is limited by overflow into line 520, which connects to a 5_.5-f‘t3 tank beneath the pump. This tank is provided with helium bubblers that operate through lines 599 and 600 and reference line 589, Indication of high level in the overflow tank causes the reactor system to be drained. Helium leaves the over- flow tank through line 523, which connects to line 522. Valves HCV-523 and HV-523 are used to block the vent line so that the overflow tank can be pressurized through the bubbler lines and salt can be discharged to the pump bowl. Line 999 connects the pump bowl to the sampler enricher. Capsules are used to remove samples of fuel from the pump bowl through this 1-1/2-in. line;-and small slugs of fuel may also be added through it. The sampler enricher is described in detall in Sec. 7.0. The lower two-thirds of the pump bowl, the overflow line end tank, and the vertical section of the suction line to the pump are installed in the pump furnace. The furnace is divided-into an upper zone around the pump bowl and a lower zone around the:overflOW tank. The upper zone has nine ~ vertical tubular heaters with a total of 22.5-kw capacity, and the lower zone has five3simi1ar;‘but'longer;-heaters with a total of 22.5-kw capacity. There are 22 thermocouples and spares on the pump, eight thermocouples on the overflow tank, and two thermocouples on line 100 inside the furnace, for use in monitoring the temperatures and controlling the heaters. 72 The upper part of the pump bowl is not cooled by the circulating fuel salt and must therefore be cooled by gas circulated over the outer surface of the pump bowl to remove the heat generated by absorption of beta and gamma radiation. The cooling gas is supplied through 3-in. line 903 at a maximum flow rate of 40O scfm. The gas flow is confined by a shroud around the bowl and is discharged to the cell atmosphere. Temperatures of the top of the pump bowl and the flanged neck are used in controlling the flow of coplant. 0il is used to cool and lubricate the pump bearings and to cool the shield block in the neck of the pump bowl. Lubricating oil for the bearings enters the top of the bearing housing through line 703 at = rate of 4 gpm, and coolant for the shield block enters through line TO4 at a rate of 8 gpm. 0il leaves the shield block through line 707 and passes through an ejector where it induces flow of oll from the bearings through line 705. The combined flow leaves the pump through line 706. The temperature of the oll supply is 150°F and the return temperature is 160°F. Line 590 is a breather pipe that connects the top of the lubri- cating oil supply tank to the topmost passages in the bearing housing to equalize the pressure between the two points. Details of the lubricating oil system are discussed in Sec. 5.4.1.4. Temperatures in the oil system on the pump are monitored by two thermocouples on the outlet oil lines. The fuel pump is driven by a 75-hp, 1150-rpm, 440-v, three-phase electric motor. The motor is installed in a steel housing that will con- tain oil and radioactive gases if either or both were to leak through the upper seal in the bearing housing. The motor is cooled by 5 gpm of process water that is circulated through a coil on the outside of the housing. Water enters the coil through line 830 and leaves through line 831. A microphone, XdbS, permits pump noises to be monitored in the control room. The electrical input to the pump motor is instrumented for voltage, . current, and power readings. The motor speed is monitored and motor tem- peratures are measured by a thermocouple (with spare). All the lines to the pump bowl have flanged joints, and the pump is assembled by means of two large flanged Jjoints. The ring-joint seals on the flanges are connected to the leak detector system {see Sec. 11.0). & Ly ¥ a 73 Fuel salt flows from the pump to the heat exchanger through line 101. The line is provided with a freeze flange joint FF-101. There are two pipeline heaters, one of 4-kw and the other of 5-kw capacity, on the section of line between the pump and the flange, and one 4-kw heater be- tween the freeze flange and the heat exchanger. Thermocouples are attached to the pipe under each heater to monitor the temperature and are used as a gulde to control the heaters. The fuel heat exchanger is of the horizontal shell-and-tube type with the fuel salt in the shell and the coolant salt in the tubes. The exchanger has three electrical heater units that are similar in construc- tion to those used on the pipelines but are considerably larger. The total heater capacity is 30 kw. Sixteen thermocouples are distributed between ten locations on the heat exchanger shell and nozzles. Fuel salt leaves the heat exchanger and returns to the reactor inlet through line 102. Coolant salt enters through line 200 and leaves through line 20l. Freeze-flange disconnects FF-200 and FF-201 are installed in those lines close to the exchanger. Line 102 contains FF-102 to Join the heat exchanger and reactor vessel, The vertical section of line 102,'directly below the heat exchanger, is heated by three calrod heaters that are attached perma- nently and have a capacity of 6 kw. Three spare heaters with an addition- al 6 kw capacity are installed on this section of line. The horizontal section of the line to the freeze flange has three removable pipeline heaters with a total of 16 kw capacity. One pipeline heater of 4 kw capacity is provided between FF-102 and the thermal shield. The temperatures on line 102 are monitored by eleven thermocouples distributed between five locations. Four of the thermocouples are in- - stalled near the location where the line enters the thermal shield and - serve to indicate the fuel temperature at the inlet to the reactor for all control and safety purposes. , ,Sélt'is introduced into the'primary circulating system or drained from 1t through'line 103, which runs from the bottom of the reactor vessel in the reactor cell to the drain tanks in the drain tank cell. The line has a freeze valve, FV-103, to provide "on-off" control of the salt flow. The valve is located within the reactor furnace so that in T4 the emergency situation of loss of electrical power, the residual heat in the furnace will be sufficient to melt the salt in the valve and cause the system to drain. A cooling gas stream of 25 to 75 scfm is supplied through line 919 and directed against the valve to maintain a frozen plug of salt. A 1.5-kw electrical heater is installed on the valve to effect a quick thaw under normal circumstances. The freeze valve has three thermocouples, each with a spare, to monitor and control the operation of the cooling gas and the heater. Line 103 is insulated and heated by passing an electric current through the pipe wall. The heating capacity is 0.3 kw/ft, resulting in a total load of 17 kw. The line temperatures are monitored by twelve thermocouples. at + AL RL4i 8 X 7 . IR MR / /7 /] LARIARIILMLY & 75 5.3 Reactor Vessel and Core A summary description of the reactor vessel and core is given in Section 2.4.1, and a simplified drawing is shown in Fig. 2.2. The general location of the reactor within the containment vessel is shown in Figs. h.4~and 4.5, 5.%.1 Deseription | f The reactor vessel is 58 in. ID and about 9% in. high. Cross ‘ : sectionel views of the vessel, access nozzle, and core are shown in Figs. 5.4 and 5.5, and the principal dimensions are given in Table 5.2. It fias designed for a pressure of 50 psig at 1300°F, using an allowable stress of 2750 psi for the INOR-8 alloy used for fabrication of all salt- containing portions (see Section II of Ref. 18, Ref. 19, and ORNL Specification JSf80-122). The properties of the INOR-8 are summarized in Table 2.2 and described in detail in Part IV. The vessel has two 58-in.-1ID torOSpherical ASME flanged and dished heads 1 in. thick. The wall thiéknessrbf the cylindrical portion is 9/16 .in., except for the top 16 in;Q which is 1 in. thick. The extra thickness is needed in the upper section to allow for 84 holes, 3/t in. in diameter, located with variable,SPacing around the top of the vessel to dis- tribute the incoming salt evenly around the circumference. Salt is delivered to the holes through a flow distributor, half-circular in cross section, and with an inside radius of about 4 in. (see Fig. 2.2), The 6-in.-diam inlet to the distributor is arranged tangentially to the vessel, and the holes enter the vessel at an angle of 30° with a tangent to the outer surface to impart a spiraling flow to the salt as 1t moves downward through the reactor-vessel-wall cooling annulus. Turbulent flow is promoted in this 1l-in.-wide annulus between the vessel wall.and the outside of the core can to improve the cooling of the wall (see ORNL Dwgs. D-BB-B-4LO4LOT7 and D-BB-B-40401). The salt then flows into the bottom head, which contains 48 swirl-straightening vanes extending radially 1l in. toward the center of the vessel. These vanes are fabricated of 1/8-in,-thick INOR-8 plate. Elimination of the swirl in the bottom head reduces the radial pressure gradient and promotes mdre even flow distribution through the core. COOLING GAS Unclassified ORNL IWG 64-8812 INLET & il COOLING GAS H*\\‘. “OUTLET “'4’74' ¥ ~ s COOLING GAS INLETS~, # 3 o ' a} 7 NG M y OOLING GAS OQUT . :n;g;g ? : | A H W1 | R d) . I | A 77T TTT T 7777277, 2777727777777 7L 77 sl | 7777777 _ vl BRI i THERMAL SHIELD COVER L | K . (WATER-COOLED) ”: i I 11 ke ! . [ '1 i |L~Frozen saLT sead R | I - AL ']I ! N -4 ‘\ é i | : HiTE i | THERMAL INSULATION 4: : i ) b .: E \ . . rrreeedxerzd | LS - s?f”frflflz 7 L~ - B ’ p ’ > ‘ L7 "fl I ] :: i w“ ya r/ / L z V\X/\ TR TTT 7 *’“1 ol [ % f TR .‘.(__. u.}.,‘d__;l__.[_-.. o X . — _.__ m WE?E -L ’, e e K _._.p._‘_.g...__.ag. .-‘.{}_&Lx\_ || de E il g SALT OUTLET To T BOTTOM OF NOZZLE PLUG E{ ] e ! SALT OUTLET TO MY B - ‘ NN ! . | \ N ) ! N | | | . i ; ’ UTLET STRAINER ‘ ] CONTROL ROD AND . 3 REMOVABLE GRAPHITE (I HANGER THIMBLE (3) , ,_.‘{1 i o] e - o STRINGERS (5) - RODS (12) b — c GRAPHITE 1 s csmggms ] . - ; BRID : o ‘ Pl A-A{\/\M"‘"“H T T P ™~y ,\.",.\!”_/\:g P |4 GRAPHITE w2 B . Bl RETA‘NER . . . . ) : . . . . . . . . ‘ E : RING Tl 1 SUPPORT % LUG (36) - A-SALY INLETY ! 7 DISTRIBUTOR | ! ) 1 | I 1 l ! ! N z' | | | ‘ 1 | GRAPHITE AND m™EAATAD i VESSEL — ! = | A CORE CAN 1 1K RESTRICTOR I RING ) s olhe . T I¥ 1ol Je |+ ¢ ol el 161,30 14 wili ¢ GRID SUPPORT PLATES R TR N TN T Ty FILL AND DRAIN LINE 2\ A DRAIN LINE HOOD ST ORAIN TUBE 2 Fig. 5.4. CROSS SECTION MSRE REACTOR VESSEL AND ACCESS NOZZLE GRALKIC JCALL - LNSHED e F s T a b INUR-8 SAMPLE ASSEMBLIES (3) GRAPHITE STRINGERS 513 FULL SIZE 104 FRACTIONAL - SIZE 9L GRAPHITE LATTICE BLOCKS ANT{-SWIRL VANES (48) ; ‘,“‘v 'g“,) Unclassified ORNL MG 64-8813 COOLANT GAS CONTROL ROD DRIVE MOTOR Housme‘_'\ DRIVE HOUSING SUPPORT BOX GRAPHITE SAMPLER STAND PIPE NO. 1§ CONTROL ROD DRIVE HOUSING NO. 3 NT gas LIFTING BAIL X__REACTOR CELL LETS o | ROOF PLUGS T@fl faal fi ] __ELECTRICAL , : Ort LEADS PLUG | ! i | | ) I :"!] : ' % ' , ' | ! | [ T | ; - il *a |: ' E : \I ] . ] ! N j 1 | ! | | i E ! : i i % : | - : i ! : : [ : | * | : | g ; CONTROL ROD DRIVE ! 1 /‘Housme NO. { ) | o | "M | | | | | L | | | I CONTROL ROD DRIVE | ! /HOUSING NO. 2 | | ! | | e / | | ' | | ! i { OUTLINE OF STAND PIPE | | NO. 2 WHEN IN PLACE l ! | | : | t | ' | ] | : ! ! | | | 1 | i i | B 5 W ] : o | i — 1 . ! i ; | l : | : : ! ! l ' i E 1 I | MAAMTDNAL DA e s 0 et 1 e, P e e e S . THIMBLE NO. 3 COOLANT GAS OUTLETS REACTYOR ACCESS PLUG FLANG Fig. 5.5. CONTROL ROD GUIDE ROLLERS | CONTROL ROD CONTROL ROD -THIMBLE NO. { THIMBLE NO. 2 THERMOCOUPLE DISCONNECTS SEARKIC SCALE - Micaks .ill..‘.’." Elevation of Control Rod Drive Housings. . mmig - = i 78 Table 5.2. Reactor Vessel and Core Design Data and Dimensions T) { A Construction material INOR-8 Inlet nozzle, sched-40, in., IPS 5 : Outlet nozzle, sched-40, in., IPS 5 : t Core vessel ; 0D, in. 59-1/8 (60 in. max) ID, in. 58 y Wall thickness, in. 9/16 Overall height, in. (to ¢ of 5-in. nozzle) 100-3/L - » Head thickness in. 1 Design pressure, psi 50 Design temperature, °F 1300 " Fuel inlet temperature, °F 1175 Fuel outlet temperature, °F 1225 Inlet Constant area distributor Cooling annulus ID, in. 56 l Cooling annulus OD, in. 58 : Graphite core | ; Diameter, in. 55-1/L v Number of fuel channels (equivalent) | 11ko . Fuel channel size, in. 1.2 x 0.4 , Core container I4, in. 0D, in. Wall thickness, in. Height, in. (rounded corners) 55-1/2 56 1/4 68 L 79 The reactor vessel 1-1/2-in. sched-40 drain line extends about 2-3/k in. into the inside of the vessel at the centerline and is covered with a protective hood to prevent debris on the bottom of the vessel from dropping into the opening. A l/2-in.-diam tube is nounted through the wall of the portion of the drain line protruding inside the vessel to allow the salt to drain completely (see ORNL Dwg. D-BB-B-40405). This tube extends through the drain line (103) and the freeze valve, FV-103. The core can, or shell, is 55-1/2 in. ID and 67-15/16 in. high and was rolled from 1/4-in.-thick INOR-8 plate (see ORNL Dwg. D-BB-B- Lok10). The can is supported, and also held down when salt is in the reactor, by a ring at the top of the can which is bolted to 36 lugs welded to the inside wall of the reactor vessel. The can, in turn, supports the graphite used és a moderator material in the reactor. The properties of the graphite are discussed in Section 5.3.2. The reactor core is formed of 513 graphite core blocks, or stringers, each 2 x 2 in. in cross section and about 67 in. long, overall, mounted in a vertical close-packed array, as shown in Figure 5.6 and ORNL Dwg D-BB-B-40L416. In addition there are 104 fractional-sized blocks at the periphery. Half-channels are machined in the four faces of each stringer to form flow passages in the assembly about 0.4 by 1.2 in. in cross section. There are 1108 full-sized passages and, counting fractional sizes, the equivalent total of 11ho full-sized passages. The dimensions of these flow channels were chosen to provide a passage that would not be blocked by small pieces of graphite and also to obtain a nearly optimum ratio of fuel to graphite in the core. The volume fraction of fuel is 0.225; the mass of fissionable material in the reactor is near the minimum, and the effect of the fuel soaking into the pores in the graphite is small.20 When not buoyed up by being'immersed in the fuel salt, the vertical graphite stringers rest on a lattice of graphite blocks, about 1 by 1-5/8 in. in cross section, laid horizontally in two layers at right angles to each other (see ORNL Dwg. D-BB-B-40420). Holes in the lattice blocks, with 4®-30' taper and 1.040 in. in smallest diam- eter, accept the 1.000-in.-diam doweled section at the lower end of 80 UNCLASSIFIED ORNL-LR-DWG 56874 R PLAN VIEW TYPICAL MODERATOR STRINGERS SAMPLE PIECE FIG. 5.6. TYPICAL GRAPHITE STRINGER ARRANGEMENT 81 each stringer with sufficient clearance to allow both angular and lateral displacement. The upper horizontal surfaces of the graphite lattice bars and stringers are tapered so that salt will not stand on them after a reactor drain. The lattice blocks are supported by a grid of 1/2-in. thick INOR-8 plates, set on edge vertically, and varying in height from about 1-5/8 in. at the core periphery to about 5-9/16 in. at the center. (See ORNL Dwg D-BB-B-40413). This supporting grid is fastened to the bottom of the core can and moves downward as the can elongates on a temperature rise. The regular pattern of the graphite stringers in the core is disrupted at the center where the control rod thimbles and the graphite and INOR-8 samples are located, see Figure 5.7. The control rod thimbles are supported from above and the samples are supported from below when no salt is in the reactor. The INOR-8 and graphite samples are contained in three baskets in the lattice position shown in Figure 5.7. Each basket can be withdrawn independently of the others. A basket must be in place at each of the three locations during reactor operation, however. Each basket is formed of 1/32-in.-thick INOR-8 plate, perforated with 3/32-in.-diam holes. The top fitting is drilled with 1/8-in.-diam holes on 1/4-in. centers for circulation of the salt and is provided with a T-shaped lifting bail. This bail permits the sample removing tool to rotate as well as 1lift the basket for better maneuverability. The upper portiofi of the basket assembly extends from 1/2 to l-in. into the fuel- salt outlet strainer and is held in position by it. The lower end of the basket is provided with an INOR-8 fitting, also drilled with 1/8-in. diam holes, which, in conjunction with the other two baskets, forms a dowel to fit into the lower graphite lattic blocks in the same manner as the graphite stringers previously described. Each basket contains four 0.250-in.-diam x 5-1/2-ft long samples of INOR-8 and five graphite sample bars, 0.250 in. x 0.470 in., as shown in Figure 5.8. The graphite bars are divided into samples of varying length (up to about 12 in.), which laid end to end total about 5-1/2 ft. The 82 TYPICAL FUEL PASSAGE NOTE: STRINGERS NOS. 7, 60 AND 6t (FIVE) ARE ZN\ ) O \.\\'I 7 Unclassified ORNL IWG 64-8814 |_~CONTROL ROD |_——GUIDE TUBE “\—GUIDE BAR \ REACTOR ’\ N {/csnrem.ma ’ \ AN - N ),/’\ | SMANTHZAN , THREE GRAPHITE AND AT e / INOR-8 REMOVABLE /] SAMPLE BASKETS 15 R\fi.’EACTOR CENTERLINE Fig. 5.7. Lottice Arrangement at Control Rods. 83 i e b T L g S N i i et £ GT88-¥9 DMI TNYHO PaTITSSBTOUN W T e S e A\ K o &'y i et i b e e e i e g 84 arrangement of the baskets and contents is exPerimental in nature and t :) will be varied during operation of the MSRE, ‘ The sample baskets are held down by a cup mounted on a 5/16-in. diam rod which is an extension of the nozzle access plug, as shown in Figure 5.4, The cup rests on the T-shaped lifting bails. A thermocouple is installed on the hold-down rod to indicate the salt temperature 1eaving.the reactor. In addition to the graphite samples in the baskets, the five graphite stringers at the center of the core can be removed, although with considerable more difficulty. The location of these stringers is indicated in Figure 5.7. The five stringers are of a special design (Types 7, 60 and 61 on ORNL Dwgs D-BB-B-kOh16, 40418 and LOS8L). They - are 2-in. x 2-in. in cross section but are 64-1/2 in. long rather than the 62-1/8 in. of the average stringer. Théy do not have the dowel section at the bottom and the hole for the hold-down rods and they rest - directly on the INOR-8 supporting.grid rather than on the graphite lattice blocks. The lattice blocks do not extend across the five stringer locations, the bpening thus providéd through the blocks per- mitting insertion of a viewing device through the core to permit obser- vation of the lower head should this.prove desirabie. Each of the five strifigers is drilled and tabped with a 3/b-in. 6 Acme thread on the upper end for an INOR-8 lifting knob, or stud, which can engage a Snaptite quick-disconnect coupling. 'They are pre- - vented from floating in the fuel salt by 1/8 in. x 1/2 in, hold-down bars welded to the strainer assembly at a level even with the top of the graphite core. (See ORNL Dwg E-BB-B-lLOSQB). The graphite core matrix is sufficiently unrestrained so that on a temperature rise the induced stresses due to expansion of the graphite will be minimized. The coefficient of expansion for the graphite is 1.3 to 1.7 x lO-6 in./in.-°F, whereas for INOR-8 it is 7.8 x 10-6 in./in.-°F (in the 70-1200°F range). This difference causes the core can to move 3/16 in. radially away from the graphite core bloéis on héatup of the reactor. To prevent an excessive amount of salt flow in the annuluar space thus created, an INOR-8 restrictor ring, 1/2 x 1/2 x 54-1/2 in. ID, surrounds the bundle of graphite stringers at the bottom (see ORNL Dwg. D-BB-B-MOAET). The stringers are restrained from excessive ‘ y;) 85 movement at the top by a graphite retainer ring, 1 x 2 x 53-1/L in, ID. This ring, in turn, is held in place\by an INOR-8 retainer ring, 3/ x 3/4 x 53-1/4 in. ID (see ORNL Dwg. D-BB-B-L0OL28 for both rings). At the top of the graphite blocks a centering bridge holds a row of stringers in position on two diameters at right angles to each other. This bridge helps to prevent shifting of the entire stringer assembly (see ORNL Dwg. D-BB-B-4oh2h). A 5/16-in.-diam INOR-8 rod passes through a 0.010-in.-wall-thickness bushing placed in a 0.375-in.-diam hole in the dowel section at the bottom of each graphite stringer. These rods alsc pass through the INOR-8 grid-supporting structure and prevent each graphite stringer from floating in the fuel salt. If & graphite stringer were to break in two, the top portion would tend to float away and leave a relatively stagnant pocket of fuel salt which might reach a higher temperature than desired. The effect of this on the reactivity and on the tempera- tures in the reactor has been studied.* To guard against this eventu- ality, a 1/16-in.~-diam INOR-8 wire is passed through a 1/8-in.-diam INOR-8 insert about 1 in. from the top of each graphite stringer, fastening the tops together and to the core can. To prevent possible overheating in a region that might otherwise have been stagnant, about Eh gpm of the salt entering the reactor is diverted into the region just above the core-can support flange in the annulus between the pressure vessel and the core can. This is accom- plished through 18 slots or channels, 0.2 by 0.2 in., cut in the core- can flange. These slots are machined at an angle of 30° to promote better miximg in the reglon. In addition, a by-pass flow of 3-22 gpm of salt will pass through the annular clearances at the core can support 39 , 'The salt leaves the reaefor,eore_and,flows throughrthe upper head to_fhe lO-in.,nozzierepening; 'It is diverted through a 5-in. ¥If a graphite stringer were to break in two near the center of the core and the upper half floated away, the reactivity increase would be 0.004% 8k/k for each 1 in. of stringer replaced by the fuel. If the entire central stringer were replaced by fuel, the reactivity in- crease would be only 0.13% 8k/k and no power or temperature excursion of consequence should result. 86 opening in the side of the nozzle to flow to the fuel circulating pump. The 10-in. nozzle also serves as an access port and support for the three control rods and for taking and placing of the four graphite- sample rods in the core matrix. A strainer made from 16-gage INOR-8 plate, with a staggered pattern of 3/32-in.-diam holes on 9/6k-in. centers, is built into the top head and access plug assembly to prevent large chips of graphite from circulating with the fuel salt. The control rods are discussed subsequently in Section 5.3.5 and the graphite sampler in Section 5.3.6. 5.3.2 Graphite A moderator is desirable in & molten-salt type reactor to achieve good neutron economy and low inventory of fissile material. It is particularly desirable that the moderator be used without cladding in order to obtain high breeding or conversion ratios. Graphite is compatible with molten salt, making it possible to design the MSRE with & heterogeneous type core, using unclad graphite as the moderator. A 2 by 2-in. cross section was adopted for the graphite core stringers in the MSRE largely because it was believed that this was about the largest size of high-density low-permeability graphite of reactor grade that could be made avallable within a reasonable amount of development time.eo The graphite for the MSRE was ordered from the National Carbon Company (New York),“' the only bidder, to ORNL Specification MET-RM-1. The graphite is a special grade, given the designation "CGB" by the National Carbon Company, and new techniques and facilities were re- quired to produce it. The graphite mapufactured for the MSRE satisfied all the requirements of the specifications except for freedom from cracks and spalls. Some of this graphite was examined and tested, and the actual requirements of the MSRE were carefully restudied, with the result that material with some cracks and spalls was accepted for use in the reactor.22 The physical and mechanical properties of the MSRE graphite are summarized in Table 5.3. The graphite 1s discussed in detail in Part IV, but some of the features, particularly those relating to the design, are briefly mentioned here. Trradiation Data: (Exposure: 1.65 x 102t Shrinkage, % With y 1080°C -0.09 nvt, 0.1 Mev) 87 3 - Teble 5.3. Properties of MSRE Core Graphite - CGB Physical Properties: Bulk density, g/cm’ 1.83 - 1.89 Porosity Accessgible (to kerosene), % 7.9 Inaccessible, 9.8 Total, % 17.7 Thermal conductivity, Btu/ft-hr-°F With grain at 68°F (calculated) 116 Normal to grain at 68°F (calculated) 63 * Temp. coefficlent of expansion, in./in.°F = With grain at 68°F 0.56 x 1966 < Normal to grain at 68°F 1.7 x 10 Specific heat, Btu/lb-°F Q°F 0.14 = 200°F 0.22 600°F 0.33 1000°F 0.39 1200°F 0.42 Matrix coefficient of permeability to 3 x 107 helium at 70°F, cm®/sec Salt absorption at 150 psig, vol % 0.20 Mechanical Strength (et 68°F): Tensile strength, psi With grein 1500 - 6200 ih#OO avg) i Normal to grain 1100 - 4500 (3200 avg) Flexural strength, psi . - With grain 3000 - 5000 (4600 avg) . Normel to grain 2000 - 3650 (3400 avg) Modulus of eleasticity, psi With grain ' 3 x 106 6 e Normal to grain 1.5 x 10 | Compressive strength, psi 8600 Chemical Purity: Ash, wt % 0.0005 - Boron, wt % 0.00008 Venadium, wt % 0.0009 Sulfur, wt % 0.0005 Oxygen, cc of ed/100 cc graphite 6.0 1 grain Across grain = 650 - T700°C -0.354 -0.24 +0.10 to -0.07 88 Use of unclad graphite in the MSRE required that the graphite be compatible with the fuel salt, fission products, and INOR-8. The graphite must not introduce prohibitive amounts of contaminants, such as oxygen, into the system. Purther, the graphite must not disintegrate or undergo excessive dimensional changes and distortion. Its thermal conductivity should not decrease too much with time. A most important characteristic is that the penetration of salt into the voids in the graphite be a minimum, since this degree of salt permeation determines the graphite temperature both during operation and after shutdown. The extent of absorption of fission-product 135 gases is of concern in that the Xe contributeg§ significantly to the poison fraction.25 Both in-pile and out-of-pile loop and capsule tests demonstrated that there need be no concern for solution of the graphite by the salt, and that there are no apparent corrosion problems.eu Other tests demonstrated that the disintegration of the graphite does not occur with or without chemical additions of fission products, either in or out of a radioactive environment.23 Although the temperatures are not thought high enough to cause the graphite to carburize the INOR-8, where the two are in direct contact and there is any likelihood of failure of the INOR-8 due to embrittlement, an INOR-8 insert has been placed be- tween the load carrying piece and the graphite. The graphite will be carefully heated in dry helium to desorb water vapor after installation in the reactor. A purge salt will be thoroughly circulated through the primary system to remove all but trace amounts of oxygen before any fuel salt is introduced. It is estimated that the oxygen in compounds in the CGB graphite and in the oxide film on the INOR-8 surfaces, does not exceed about 130 Ppm of the purge salt, by weight. The purge salt, on an as-received basis, is estimated to contain no more than 200 ppm of oxide ion; thfis, the salt, with its oxide saturation 1imit of about 1000 ppm, can reduce the oxygen in the primary system to satisfactory levels before the uranium- bearing salt is added.25’ 26, 27 The thermal conductivity of the graphite will probably decrease by about a factor of three, based on data taken in high-temperature i “‘ . # »} 1 0 89 | irradiation tests. This loss was taken into account in the reactor design and an even greater reductien could be tolerated without encountering undue difficulties.25 Shrinkage in the graphite will occur in proportion to the inte- grated fast neutron flux. The radial flux gradient in the core will cause the inner stringers to shorten at a greater rate, resulting in the top of the graphite core matrix gradually becoming slightly dished. Based on data taken on similar graphite, the axial shrinkage rate of a stringer located at the point of maximum flux in the MSRE for one year of operation at the 10-Mw reactor power level was estimated to be 0.1k in./yr. The radial shrinkage was estimated to be roughly one-half of that in the axisl direction. The radial flux gradient in the core will cause uneven shrinkage in each stringer, and the resulting unsymmetrical distribution of stresses will tend to bow the stringers outward to give a slight barrel shape to the core. The maximum bowing effect was esti- mated to be about 0.1 in./yr for a stringer at the point of maximum flux and with continuous operation at 10 Mw, The widening of the fuel passages, and other related effects of graphite shrinkage, were studied from the nuclear standpoint and found to amount to changes in the reac- tivity effect of less than 0.66 Ak/k per year of full-power operation, and are not of conseQuence.eB’ 23 The nuclear aspects of graphite shrinkage are discussed in detail in Section 14.2 of Part III. In designing the graphite stringers for stresses induced by tem- perature gradients, it was decided to 1imit the rate of temperature rise to about 609F/hr. Preheating is accomplished by circulation of helium in the primary system, using ‘the fuel pump as an inefficient blower. Heat is 1ntroduced through use of the electric resistance heaters installed throughout the primary and secondary systems.30 Even though the MSRE graphite has a density of about 1.87,. it con- tains about 16% by volume of total voids and % by volume of voids that are interconnected and accessible from the surface. The graphite, as produced for the MSRE, however, has pore openings that average less than 0.3 u in’ dlameter " Slnce the salt does not wet the graphite, the surface tension and contact angle are such as to limit the salt penetration to less than the-permitted amount of 0.5% by volume of the graphite at 165 i %0 | - psia. The heat produced in the graphite by this quantity of fuel salt ‘E! 4 under full-power conditions of 10 Mw increases the average graphite tem- perature by about 1°F.51 Fission products entrapped in the graphite with the salt will continue to generate heat after the remainder of the fuel salt has been drained from the reactor. With the cooling medium thus withdrawn, and with no other means of heat removal effective, it has been estimated that the temperature rise of the graphite would be less than 100°F in 48 hr.”° Despite the considerable amount of preliminary-tesfing expended & in development of a graphite for use in the MSRE, it is recognized N that some uncertainties exist that can be resolved only by operation - of the rea.ctor.55 The behavidr of the graphite will be monitored by periodic removal and examination of samples placed near the center of the core. Full-sized pieces located in the core adjacent to the samples can be examined in place by means of a periscope, or can be withdrawn infrequently for hot-cell examination by removing the reactor vessel access nozzle plug and control rod thimble assembly. 5.5.3 Fluid Dynamics, Temperature Distribution, and Solids Deposition 5.3.3.1 General. A general description of the flow through the reactor vessel and core is given in Section 5.3.1. Models were used to investigate the fluid dynamics and heat trans- . fer within the reactor vessel, but prior to these studies, several decisions were made early in the project to lnitiate the design efforst. One of these was to choose a right cylindrical shape for the vessel, mainly because of the ease of manufacture and because the flow pattern could be fairly well predicted. Preliminary studies of the vessel size as a function of the critical mass required:indicated anEQUAL RPM {-TO-1 GEARS AlIR IN\ 5% ~=-SPROCKET CHAIN SN A S N O S AL S S SIS S S ik I I I I | | [ | I i t I I | | | | | | | | | | | | i ¥ Jfi” REACTOR VESSEL GELL | B ASSSSSSN J e THIMBLE REAGTOR GORE l e — POISON ELEMENTS [ 1yl «—-TEMPERATURE ;v 1400°F ||~ POSITION INDICATOR AIR FLOW RESTRICTOR —=— AIR DISCHARGE - RADIAL PORTS E Fig. 5.15. Diagram of Control Rod Drive. 112 The control rods are heated principally by the absorption of fission capture and fission-product decay gamma rays and the absorp- tion of recoil kinetic energy of the products of reaction.lLs The poison elements are cooled by 15 scfm of cell atmosphere gas (95% NQ’ 5% 02) supplied at 150°F through line 915 to the flexible positioning hose of each rod (&5 scfm per rod), the gas returning upwards around the canned poison sections to be exhausted to the reactor containment cell atmosphere. The gas discharge temperature is estimated to be about 1100°F and the poison elements may operate at a maximum tempera- ture of about 1350°F. Complete loss of cooling air with the reactor at full power would cause the maximum temperature in the control rod to rise to about 1500°F. A positive-position indicator is provided for the lower end of the rod which permits recalibration of the position-indicating de- vices, which are related to the upper end of the rod, should there be variations in the length. The accuracy of rod position indication needed for safe reactor operation was established as *0.2 in.h6 Development tests indicated that variations in length greater than this could be expected when dropping the rods in simulated scram conditions at operating temperatures. Positive indication of position of the lower end is provided by the cooling gas flow down the center of the flexible hose. A nozzle with radial ports is attached to the bottom end and a restrictor, or throat, is welded to the guide bar cage at a known point near the bottom of the thimble. When the nozzle passes through the throat, the change in pressure drop in the gas flow through the rod assembly is readily apparent and gives a position indication to within less than 0.1 in. the position-indicating instruments can be calibrated against this known position of the lower end of the rod. (See Figure 2.2, p. 49, Ref, 122.) 5.3.5.3 Control Rod Worth. Each of the three rods, when fully inserted and the other two completely withdrawn, has a worth of 2.8% Ak/k.* When all three rods are completely inserted, the total worth is 6.7% Ak/k.¥ At the maximum withdrawal rate of 0.5 in./sec, normally limited to one rod at a time, the change in reactivity is 0.04% (Lk/k)/sec.* Simultaneous insertion of all three rods at a $* » flég 113 rate of 0.5 in./sec causes a change in reactivity of 0.09% (Ak/k)/sec.* These and other control rod constants are summarized in Table 5.4. A discussion of the nuclear aspects of the rods is given in Part III. Instrumentation is described in Part I1I. 5.%3.6 Graphite Sampler One of the objectives of the MSRE is to investigate the behavior of the unclad graphite moderator in the reactor environment. Thus, the reactor was designed for periodic removal of graphite specimens from near the center of the core. The samples are exposed to much the same salt velocity, temperature, and nuclear flux as the graphite stringers which make up the core matrix. The specimens can be with- drawn only when the reactor is inoperative and the fuel salt is drained from the primary circulating system. When & sample is removed for analysis, it must be replaced by another sample in ofder to maintain the same flow pattern through the core. The three graphite sample baskets mounted vertically within a stringer position and the five removable stringers at the center of the core have been described in Section 5.3.1. The small baskets can be removed or replaced more or less routinely through the sample access nozzle (4o be described subsequently). Access to the five stringers is obtained through removal of the entire reactor-vessel- access-nozzle plug assembly. While this i1s accomplished through a special work shield provided for the purpose, it is not a routine procedure. . o As shown in Figs. 5.4, the graphite'-sa.mple‘ access plug fits into the"sa'mple access nozzle. The INOR-8 plug is 1.610 in. ID x 2.375 in. OD x 46-13/32 in. long and terminates at the top in a T-in. flange. The flange is fltted with a h -in. -diam O- -ring closure. The bottom of the plug 1s contoured to help dlrect the flow of - fuel salt to the gide outlet of the 10-in. reactor-vessel nozzle The plug is cooled by cell atmosphere gas (95% Né,_ % O ) introduced at the center through a l/2-1n sched-ho stalnless steel pipe (see Fig 5.4 ). (This *¥For thorium-containing and partially enriched fuel salt. For control rod data with highly enriched fuel, see Table 5.k. 114 cooling tube has a two-bolt flange at the top to permit it to be with- drawn from the graphite sample access nozzle during maintenance or sampling procedures and temporarily replaced with a metal-sheathed heater of the "Firerod" type. This arrangement assures melting of any residual salt to permit withdrawal of the sample access nozzle and its attached hold-down rod and cup.) The cooling-gas flow is adjuéted during reactor operation to freeze fuel salt in the 1/8- to 1/4-in. tapered anmilus between the plug and the nozzle to obtain a seal. The O-ring closure is buffered and leak-detected with helium. The INOR-8 graphite-sample access nozzle is 2.421 in. ID x 2.875 in. OD x 39-17/32 in. long, and is welded to the closure for the 10-in. reactor-vessel access nozzle, as shown in Fig. 5.4, A flange at the upper end bolts to the mating flange on the sample access plug with an O-ring joint (previously mentioned) and also bolts to the graphite- sampler standpipe. The standpipe connections is through a 10~in.-diam by 8-in.-long stainless steel bellows, which permits relative movement of the standpipe and the reactor vessel. Two different graphite-sampler standpipes are available for joining the reactor access nozzle to the opening in the reactor-contain- ment roof plug. The one left in place, and designated "No. 1," is used when taking one of the small graphite-sample assemblies. Standpipe No. 2, which will be described subsequently, is used when removing and replacing the 2 by 2-in. graphite stringers. Standpipe No. 1 is fabricated of stainless steel and is 19-3.4 in. ID x 20 in. OD x 8 ft 10-1/8 in. high. All joints and connections are gas-tight, and the standpipe is provided with purge and off-gas con- nections, As indicated in Figs. 5.4, 5.5, and 5.16 the upper end of the standpipe is bolted to a 40-in.-diam stainless steel liner set into the lower magnetite concrete roof plug. The lower end of the standpipe is fitted with the bellows extension which is bolted to the graphite- sample access nozzle. During normal power operation the liner opening is closed with a magnetite-concrete plug 35-1/2 in. thick, 41-1/2 in. OD, and weigh- ing about 6000 1b. 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The 5-1/2- ‘:) ft-thick ordinary concrete shield block, or roof plug, would cover these openings during reactor operation. When taking a graphite sample, with the reactor shut down and drained of fuel salt, the upper shield block is taken away, the mag- netite concrete plug is removed from the top of the liner, and a 3-ft- high working shield is installed by placing it on the lower shield block above the opening. This working shield (see Fig. 5.17) has walls of L-in.-thick lead, is canned in stainless steel, and weighs about 8250 1b. A gas-tight seal is made by its weight bearing on two Teflon O-ring seals on the bottom periphery (see ORNL Dwg. D-BB-C- 40657). A work plug inserted in the top of the working shield is 12 in. thick and contains & 3-in.-diam, heavy plate-glass viewing port, tool openings, illuminating light, and purge and off-gas connections. The work plug sits on Teflon gaskets to make a gas-tight,seal;' The plug can be rotated by a gear and piniofi arrangenent (see. ORNL Dwg. E-BB-C-40646) . | The 40-in.-diam liner in the lower roof plug and the 20-in.-diam graphite-sampler standpipe No. 1 are not concentfic'but1have circum- ferences which are almost tangent. The crescent-shapéd qpening thus provided to one side of the standpipe gives acéess to the control-rod- drive meéhanisms. Maintenance 6f this equipment can be aCcomplished - through the work shield, The shield can also be used to élear thé equipment from the 10-in. reactor-vessel access nozzle to remove the five graphite stringers at the center of the core or to'view the lowver head of the vessel. | In brief, the procedure for taking a graphité samplé is as follows, 1T~ BB First, the upper concrete shield block is removed and the 40-in.-diam concrete plug is taken out of the lower shield block. The work shield is then placed over the standpipe opening, a specimen assembly in an unexposed sample holder with a top cover, an empty‘specimen holder with no top cover are placed'in the standpipe in the wells provided. The standpipe is then carefully purged with nitrogen or helium gas until the atmosphere is acceptable for entry into the reactor circulating system. Working with remotely operated tooling through the work plug, ' ;) UNCLASSIFIED ORNL-DWG. 64-6745 117 WORK PLUG DRIVE GEARS WORK PLUG WORK SHIELD LEAD GLASS VIEWING WINDOWS [} S S ) ! %;/fi == TOOL BUSHING WORK SHIELD FOR GRAPHITE SAMPLER FIG. 3.17 118 the sample access plug is unbolted from the sample access nozzle flange in the bellows extension at the bottom of the standpipe. The 1/2-in. cooling-gas lines are disconnected from the access plug by use of the quick-disconnect couplings. The access plug, with its attached hold- down rod, is then withdrawn and set aside in the rack provided in the standpipe. A special tool can then be inserted through the graphite- sample access nozzle to the top of the core to engage and withdraw | one of the exposed graphite-sample assemblies. This is placed in the empty specimen holder and the top cover front the unexposed specimen holder installed on it. The unexposed specimen assembly is then inserted into the core, and the access plug is replaced. The stahd- pipe is purged of radiocactive gases to the off-gas system. After a suitable decay period the graphite sample is transferred to a special carrier for transport to the analytical laboratory in the X-10 area. Should it be necessary to remove and replace any of the five 2 by 2-in. stringers from the center of the core, the reactor would be shut down and drained, the upper roof block would be removed, the round plug in the lower roof block would be lifted and set aside, and the work shield, with its work plug, would be set in place. Stand- pipe No. 1 would then be disconnected, which also necessitates discon- nection and removal of the control-rod-drive assemblies. After setting the working shield aside, the overhead crane would be used to 1lift standpipe No. 1 and to set standpipe No. 2 in place., This standpipe is 34-1/2 in. OD and is fabricated of 1ll-gage stainless steel. The top flange of the standpipe attaches to the lower roof block in the same manner as standpipe No. 1. The lower end attaches to the 10-in. access nozzle flange. Then, by working with special tooling through the work plug, the plug in the 10-in. access nozzle would be removed and the 2 by 2-in. graphite stringers would be withdrawn from the core matrix. 5.3.7T Mechanical Design of Reactor Vessel The reactor-vessel-shell and head thickness requirements were determined by the rules of the ASME Unfired Pressure Vessel Code, Section VIII.h7 119 The vessel design conditions were taken as 50 psig and 1300°F. The allowable stress used in the various computations was 2750 psi. The allowable stress for INOR-8 changes with temperature as shown in Fig. 5.18. The stress values shown in this figure are for wrought and annealed sheet, plate, piping and tubing, and do not apply to weld or cast metal. However, tests have shown welds to have properties as good as the parentrmetal. The allowable stresses used in the design of the reactor were based on the lowest value obtained from any of the following criteria:55 1. One-fourth of the minimum specified tensile strength, adjusted for temperature variation. As shown in Fig. 5.18 this criterion was controlling in the O - 200°F range. 2. Two-thirds of the minimum specified yield strength, adjusted for temperature variation. This criterion established the allowable stress in the 200 - 900°F range. 3. Four-fifths of the stress to produce rupture in 100,000 hr. In the temperature range of 900 - 1030°F this factor was controlling. L, fTwo-thirds of the stress to produce a creep rate of 0.1% in 10,000 hr. This criterion established the allowable stress above 1030°F, which is the range for which the pressure vessel must be designed. The first three of the above criteria correspond to standard practices (see Ref L7, Appendix Q, p 174). A safety factor of two- thirds was applied in the fourth criterion to allow for variation between batches of material and other uncertainties. In 1962 the ASME code committees accepted INOR-8 (Hastelloy N) as a material of construction for unfired pressure vessels. The allowable stresses under the code exceed those used in the MSRE design by about 20%. The curves of Fig. 5.18 show that the allowable stresses drop from 6000 psi at 1200°F to 1900 psi at 14OO°F and emphasize the need to maintain effective cooling of the pressure-stressed portions of the system. Under normal operating conditions the wall of the pressure vessel is estimated to be no hotter than 1180°F, the lower head 1190°F, and the upper head 1230°F. A design temperature of 1300°F was taken in order to provide some additional margin. The low allowable stress Stress - psi in thousands 120 Unclassified ‘ ORNL ING 64-8818 0 | | | i o [ 1/4 TS ol 2/3 YS :I: ) -l— 2/3 0.1 CRU — 4/5 RS = N - — - . — —— e - . | — R —— \ 20 — — .\‘-' S— ~ \—l—- * e— o — — 15 Q\ \ S \ Ty, \ ~N \ . 10 \ \\ 8 \ \l — = = 1/4 Tensile Strength (TS) \\ \ 6= —.— - 2/3 Yield Strength (¥5) N T e ———— 4/5 Rupture Strength (].05 hrs) (RS) \ bb— —--—~ 2/3 0.1 Creep Rate Unit (CRU) A \ —teeremeees Meximum Alloweble Stress \ \ 3 — \ N 2 \ 1 0 200 4oo 600 800 1000 1200 1400 Temperature - °F Figure 5.18. Criteria for Establishing Static Design Stresses in INOR-8. 121 of 2750 psi used for design is based on the long-term creep properties of the material at leOOF, but it is to be noted that even at lBOOOF the tensile strength and yield strength of the material are still above 20,000 and 20,000 psi, respectively. This implies that short exposures to abnormally high temperatures would not produce complete failure of the equipment. Estimates of the thicknesses of the material required were based on standard formulae.18 In all cases the actual thicknesses used were greater than those calculated to be required. Estimates of the stresses at the nozzles were based on early predictions of the forces and moments imposed by the piping system.18 Since the calculated stresses were 53 well within the acceptable range, the values were not revised to correspond with thé nozzle reactions obtained by more refinéd analyses of the piping systems. The portions of the reactor pressure vessel receiving special study were the upper and lower heads, the shell, the inlet nozzle and flow distributor, and the outlet nozzle. The INOR-8 core grid support bars were also investigated. Stresses induced by possible thermal gradients were considered in all cases. The stresses imposed on the reactor support lug by the support rod were found to be less than two-thirds of the yield stress but higher than the allowable two-thirds of the 0.1% CRU (Creep Rate Unit). As a result, it can be anticipated that a small amount of creep could -occur, increasing the contact area and rapidly lowering the contact stress to within an'acceptableifange (see page 48, Ref. 18). The graphite lattice blocks were designed on the basis of bending stress estimates at points of maximum moment. The calculated stresses were less than 100 psi (see page 38, Ref. 18). 5.3.8 Tubes for'Neutrdn_Source and.SE§cial Detectors Thimbles are provided in the thermal shield for a neutron source and for two special neutron detectors for use primarily during the critical experiments.' The inherent source of neutrons in the unirradi- ated fuel from reactions between the alpha particles emitted by the . . a2 . . i uranium, primarily 3)+U, and the beryllium, fluorine, and lithium nuclei will be 3 to 5 x lO5 neutrons per second. This is adequate for 122 safety purposes; but a stronger source is desirable for following the approach to criticality, and an antimony beryllium or polonium beryllium 9 neutron source of about 10“ neutrons per second will be provided for this purpose. The source will be inserted in a thimble made from a 1-1/2-in. sched-40 pipe, 9-1/2 ft long, located in plug No. 1 in the west- northwest sector of the thermasl shield (see ORNL Drawing EQDD-B-hO726). The source pipe is protected from damage by the l-in.-diam steel balls filling the thermal shield by a surrounding half-section of 8-in. sched-40 stainless steel pipe. The location in the thermal shield was chosen because the temperature will be low, so any standard source can be used without concern for its thermal properties, The source is on the opposite side from the nuclear instrument thimble and near the inner wall of the thermal shield. The source will be placed in a cage and will be lowered or raised by a simple arrangement of a small, braided, wire cable fastened to the cage and extended to the operating floor level. The two tubes for the special neutron detectors are similar to the source tube but are 2-in. sched-10 pipe and are located in the northeast and southeast sectors of the thermal shield. The chambers in these tubes are intended for use only during the critical experi- ments and the early power experiments. Use of the neutron source during startup of the reactor is dis- cussed in detail in Part III and Part VIII. The fission chamber instrumentation is described under Instrumentation, Part IT. 5.5.9 Support The reactor vessel is supported from the top removable cover of the thermal shield by twelve hanger-rod assemblies. As shown in Fig. 5.19, the bottoms of these assemblies are pinned to lugs welded to the reactor vessel just above the flow distributor. The tops 6f the assemblies are pinned to the support plates in the cover. The cover is supported by the thermal shield assembly, which, in turn, rests on the I-beams of the major support structure in the containment vessel. The thermal shield will be described subsequently in Section 5.5.11, 123 Unclassified ORNI, DWG 64-8819 Y IPZL PP L L Ll Thermal Shield Cover 1-1/4 in. Dia Pin / 3\<3(>( >(><>( _Yd e X /,(\ Xx/ L 6 NC Threads (Right Hand) 1-1/4 in. Dia INOR-8 |/ Hanger Rods (12) ~ 3 1no—.1 ~ 24 in. e 3/4-in. Thick / INOR-8 Support Lug Welded to - . Vessel — p—3-3/8 1n 1-1/% in. Dia INOR-8 Pin . Figure 5.19. Reactor Vessel Hanger Rods 124 Since the reactor vessel is not accessible when in position inside kfij the thermal éhield, the vessel will be attached to the thermal shield cover in a Jjob cutside the reactor cell. All adjustments, attachment of thermocouples, etec., including final inspection, will be completed before the reactor and cover assembly is lowered into position. Maint- enance on the reactor, other than that which can be accomplished through the reactor access nozzle, requires lifting of the cover and the attached reactor from the reactor cell. The twelve hanger rods are 1-1/4 in. in diameter and about 24 in, long. They are threaded for 3 in. on each end (opposite hands) with 1-1/2-in. 6-NC threads, and are fabricated of INOR-8. A hex section | 5 in the center is for applying a wrench in the turnbuckle arrangement to level the reactor and to distribute the load evenly between the hanger rods. The support brackets, or lugs, welded to the reactor vessel, are fabricated of INOR-8 and are, for the most part, of 3/L-in. plate. The centerline of the pin hole is about 1-3/8 in. from the wall of the vessel. The pin is 1-1/4 in. in diameter and is made of INOR-8 (see ORNL Drawing D-BB-B-4LO4LOT). The support arrangement is such that the reactor vessel can be considered to be anchored at the support lugs. The portion of the vessel below this elevation is free to expand downward on a temperature rise with essentially no restraint. Expansion of the portion above the elevation of the support lugs creates forces and moments - -on the F connecting piping which are considered in the flexibility analysis of the piping, as discussed in Section 5.6.2, following. < The temperature and stress distributions in the hanger rods were estimated using derived equations and analog computer solutions.sh’55 The reactor vessel and contents weigh about‘50,000 lb, giving a static stress of about 2000 psi per rod. The top end of the rods are cooled by conduction to the water-cooled thermal-shield cover and are assumed to be at about 200°F. Assuming the lower end of the rods to be at a maximm of 1250°F, and the gamma heating to be a maximum of 0.23 w/cec, the combination of the thermal stress due to the temperature gradient - and the static load is a maximum at the cool end. This value is 7350 -’ O N w3 " i} 125 psi and is well within the allowable stress of 24,000 psi for INOR-8 at 200°F., At the hot end the estimated combined stress is ~2700 psi, which is within the allowable stress of 3500 psi at 1300°F. The maximum temperature occurs about 1/2 in. from the reactor vessel and is estimated to be about 1280°F; the combined stress at this point was determined to be 2500 psi. 5.3.10 Thermal Shield The primary functions of the thermal shield, which might be more properly called the "internal shield," are to reduce the radiation damage to the reactor containment vessel and to cell equipment, to serve as part of the biological shielding, and to provide a support for the reactor vessel. It is estimated that the thermal shield reduces the tdtal neutron dosage inside the containment vessel by a factor of a.bc:xu’c'lo,+ and attenuates the gamma irradiation by a factor of about 105. - The shield is a vater-cooled, steel- and water-filled container completely surrounding the reactor vessel. A general exterior view of the thermal shield before installation is shown in Fig. 5.20. The shield is about 10.4 £t OD by 7.8 ft ID and 12.5 £t high overall. The 14-in.-wide annular space is filled with l-in.-diam carbon steel balls..‘The shield cooling water circulates through the interstitial spaces. Including the 1l-in.-thick plate, of which the thermal shield is primafily'constructed, the shield is 16 in. thick, 50% of which is iron and 50% is water. Type 304 stainless steel is used as the con- struction material because fast neutron irradiation of the inner wall could raise the nil ductility.temperature (NDT) of carbon steel above fhe_operating temperature in less than one year of full-power operation. The,suppoft-structure, however, is constructed of carbon steel. The weight of the. COmplete”thermal-shield, including the water, is esti- mated to be about 125 tons. The cooling-water system is designed to 'remove “about ‘600 kv of heat ut the actual cooling load is estimated | to be considerably less than thls. - Six separate pieces make up the thermal shield assembly: +the base, the cylindrical sectlon, three removable sections, or plugs, and the removable top cover. The plugs fill the slots in the cylindrical section through which the reactor fill and drain line, the fuel-salt inlet line L7 Thermal Shield Prior to Installation. .20. 5 Fig ey 127 to the reactor, and the fuel-salt outlet line must pass as the reactor is lowered into position. The base and cylindrical section are per- manently installed in the reactor cell. [See ORNL Dwgs E-BB-D-40729 (elev), E-BB-D-40730 (plan), and E-BB-D-40724 (assembly and gectionsfl 5.3.10.1 Structural. The base is essentlally a flat, rectangular tank about 18 in. deep which rests on & grid of radial beams at the bottom of the reactor cell (see ORNL Dwg. E-KK-D-40723). The base supports the entire thermal shield and the reactor vessel and is the anchor point in the fuel piping system. The base is welded to the radisl support beams to prevent shifting. The base contains fifteen 8-in., 20-1b/ft, wide-flange, carbon steel I-beams (ASTM A-36) arranged in two layers, with the six beams in the bottom layer at right angles to the nine beams in the top layer. The beams are welded to each other at all intersections and to the 5/h-in.—thick 304 stainless steel top and bottom plates, the former béing accomplished by 2-in.-diam plug welds on about 15-in. centers. The 3/4-in.-thick 304 stainless steel gide plates are welded to the ends of the support grid beams. Attached to, and part of, the base is a vertical section formed to fit the inside curvature of the bottom hemispherical head of the reactor cell vessel. The outer hemispheriéal plate, the inner semicircular plate, and the inner conical-shaped "skirt" plate of this vertical pro- Jection aré 1-in.-thick 304 stainless steel. The projection is internally reinforced with six 3/k-in.-thick radial web plates. The cylindrical section 1s fabricated of l-in.-thick 30k stainless steel and is 151 in. high, 125 in. OD, and 93 in. ID. The lh-in.-wide annulus is divided into %0° Ségments'by twelve l-in.-thick radial reinforcing web plates. The'plafes are perforated with 2-in.-diam holes in a pattern td promote'éffidient circulation of the cooling water. The anmilus is filled with approximately 70 tons (475 ft3) of 1-in.-dlam carbon steei balls,_arouhd which the cooling water circulates. A large cutout in the bottom of the cylinder fits over the vertical projection on the base, mentioned abové, The cylinder is slotted in three places'to accommodate the réactor fuél;salt inlet (line 102), the fuel-salt outlet (line 100), and the reactor fill and drain line (1ine 103). A 37-1/4-in.-ID pocket is provided in the side of the 128 cylinder for the neutron instrument tube. At two points near the inner surface of the thermal shield, at about the northeast and south- east positions, 2-in. sched-10 pipes about 10 ft long are mounted vertically to serve as thimbles for the special neutron detector lnstru- mentation. These tubes extend about 8 in. above the top of the thermal shield. The portion of the thimble inside the shield is separated from the l-in. steel balls by a semicircular section of 8-in. pipe. A similar arrangement at the west-northwest position, but using a 1-1/2-in. sched-40 pipe, serves as the neutron source tube (see Section 5.3.8). The three plugs that slip vertically into the slots in the cylindrical portion are primarily constructed of 1l-in.-thick 304 stainless steel plate. The portions that fit over the fuel inlet and outlet lines include semicircular sections of 20-in. pipe.' The plugs are also filled with 1l-in.-diam carbon steel balls. Each plug is pro- vided with 1/2-in. sched-40 cooling-water connections at the top, the inlet pipe dipping on the inside to near the bottom of the plug. The thermal shield cover is fabricated of l1-in.-thick 304 stain- less steel plate and is about 79-3/4 in. OD by 16 in. thick. A 22-5/8-in.-diam hole through the center is provided by a 22-in.-long section of 24-in. sched-40 pipe; the reactor access nozzle passes through this opening. The cover is divided into 30° segments by twelve l-in.-thick radial reinforcing web plates. These plates project beyond the circumference of the cover for about 4 in. and rest on the top surface of the cylindrical portion. The projections, which carry the weight of the cover and the reactor vessel, are reinforced with 3/8 in. plate on each side to give each a total bearing surface about l—5/h in, wide by 4 in. long. The web plates are perforated with 3/L-in.-diam holes spaced to promote efficient circulation of the cooling water. Each of the wedge-shaped segments in the cover between the radial plates contains four l-in.-thick carbon steel plates, spaced about 1l-in. apart, to serve as shielding. At the outer circumference of the cover are sixty-three vertical 2-in. pipe penetrations through which the reactor furnace heaters are inserted (see Section 5.3.11). At about the northwest position on the 3 129 cover, a 1/4-in.-thick rolled plate sleeve, 5-3/4 in. ID, provides access to the heaters at the freeze valve on the drain line, FV-103. Two nozzles ofi2-in. sched-4o pipe serve as the cooling-water inlet and outlet connections. 5.3,10.2 Cooling. The thermal shield is cooled by a flow of about 100 gpm of treated water containing potassium nitrite and potassium borate as corrosion inhibitors.' (The treated cooling-water-system water chemistry is discussed in Section'15.2.3). Water is supplied to the thermal shield through the 2-1/2-in. line 84k, It flows in series through the base, the cylindrical portion, and then through the cover.56 At appropriate points, water is withdrawn from the cylindriceal portion in l/2—in. plpes to flow through one of the three plugs,.after which 1t returns to the cylindrical portion. The cooling water enters the base through a 2-1/2-in. pipe on the north side and flows through the base to the south side and upward through the vertical projection of the base, The water is then con- ducted through the 2-~1/2-in. line 844-A to the bottom of the cylindrical portion. The water moves around the li-in.-wide annular space in a counter-clockwise direction (viewed from above), flowing through 2-in.- diam holes in the radial web plates, which are spaced to give the great- est circulation rate near the top of the shield. Three l/2-in, pipe connectlions at the top withdraw some of the water for circulation through the plugs, after which it is returned to the cylindricél portion (see ORNI, E-BB-D-4072k4). " The water leaves the cylindrical part of the thermal shield throfigh the 2-1/2-in, line 844-B and flows to the cover. The water flow inkthe'cover is in & counter-clockwise direction (viewed from above) and follows a serpentine course as a result of the spacing of the 5/h-in.-diam.holes'in the radial web plates (see ORNL Dwg. E-BB-D-40727). The water leaves the top cover through a 2-1/2-in. pipe (1ine 845). - | ' | | ‘ - The cooling-water system was designed to remove about 600 kw (2 x 10° Btu/hr) of heat. At a flow rate of 100 gpm, the temperature rise of the water flowing through the thermal shield is about L402°F. In case of loss of water flow, the heat capacity of the material in At 130 the shield is such that the reactor operation could continue at the 10-Mw reactor power level for about 3 hr before the water tempera- ture would rise sufficiently to create a vapor pressure exceeding the design value of 20 psig.57 5.5.10.3 Mechanical Design. The vessel was designed in accordance with the provisions in the ASME Unfired Pressure Vessel Code, Section VIII, k5 It was hydrostatically tested at 32 psig at room temperature.58 A 1/2-in. relief valve, set at 20 psig, is incorporated in the cooling- water supply system. As a further protection, the cooling-water circu- lating pump has a pressure-actuated cutoff switch in the discharge set at 22 psig. 5.3.10.4 Shielding Considerations. Radiation damage to the steel in the containment vessel wall is not considered to be a significant N problem unless the fast neutron (»1 Mev) exposure exceeds lO]‘8 n/e 2.59 - This would be an exposure corresponding to 10 yr of operation at a 10-Mw reactor power level with the containment vessel exposed to a fast flux of 5 X lO9 n/cmz-sec. The thermal shield has a total thickness of 16 in, 50% of which is Fe and 50% is H,0, & 12-in. gap between the reactor and the shield, and an estimated escaping neutron flux of about 1.5 x 10° n/ca*-sec.”? The biological shielding required in the roof above the reactor is not materially reduced by the presence of the thermal shield in that the aforementioned 22-5/8-in.-diam hole through the center of the thermal-shield cover permits direct impingemént of radiation from the 1 reactor vessel over a fairly wide area of the roof plugs. The thermal shield does, however, make an important reduction in the amount of s biological shielding needed at the coolant-salt penetrations of the containment vessel wall. | As previously stated, the cooling-water system is capable of removing 600 kw of heat. The nuclear heating in the thermal shield is expected to contribute to less than 100 kw of heat. The amount of heat transmitted from the reactor furnace to the thermal shield through the thermal insulation is estimated to be less than 50 kw. 1, 131 5.3.11 Heaters The 1l-in.-wide annular space between the thermal insulation on “the inside of the thermal shield and the reactor vessel wall is heated by electrical resistance-type heaters to form a furnace. A total of about 68 kw of heat can be supplied by one-hundred twenty six lengths of 3/8-in. by 0.035-in.-wall-thickness Inconel tubing, each 8 ft T-1/2 in. to 9 £+t 11 in. long, through which the current is passed (see ORNL Dwg. E-MM-B-56225). This furnace provides the heat to the reactor vessel during warmup and maeintains the vessel at temperature during low-power operation. The reactor furnace heater tubing is in the form of sixty-three U-tubes, which are arranged in nine removable sections of seven U-tubes each. Each of the U-tubes is inserted in a 2-in.-OD by 0.065-in,-wall- thickness 304 stainless steel thimble, which is suspended from the top cover of the thermal shield. The tops of the thimbles extend about 6 in. above the top cover and are flared to about 2-3/8 in. in diameter to facilitate insertion of the heater U-tubes. The centers of the thimbles are about 2.615 in., from each other and about 1-7/8 in. from the insulation can. The distance between the centers of the legs of the U-tubes is 3/4 in. The U-tube assemblies are suspended from the junction box for each assembly. The junction boxes are fabricated of 1l-gage 30k stainless steel, are about 4 in. by 4 in. in cross section and about 18 in. long, and are curved longitudinally to thé segment of -a circle about 37-1/2'in.'in radius. The.junction boxes sit on top of the. thimbles which pass through the thermal shield cover. Each Junction box is provided with a lifting bail at the center of gravity to permit vithdrawal of the seven U-tube assemblies as a complete unit. The seven U~tubes in each section are electrically connected in series so that each Jjunction box has but two electrical power leads. The lead wire inside the Jjunction box is solid No. 10 Alloy 99 soft- temper nickel, insulated with'fish-spine ceramic beads (Saxonburg Ceramic Company Part No. P-897). The lead wires are connected to a male plug mounted on top of the junction box. The matching female socket is fitted with a lifting bail to facilitate remote manipulation. 132 The socket is connected by cables to the terminal boxes mounted on the support structure. The top 31-1/2 in. of each heater U-tube leg is constructed of solid Inconel rod, 3/8 in. in diameter, and therefore does not heat to as high a temperature as the lower tubular portion., The solid rod is formed at the top to electrically connect the U-tubes in series. Abvout 27 in. of the upper portion of each U-tube assembly is stiffened by being incased in & 1-5/8-in.-0D by 0.065-in.-wall- thickness 304 stainless steel tube. Ceramic insulators (American Lava Company, Type A) position the U-tube legs within this tube. Ceramic standoff insulators of the same material are also spaced at regular intervals along the lower legs of the U-tubes to prevent their contact with the thimble walls. The U-tubes in five of the sections are about 12 ft long overall, including the solid portions, and those in the remaining four sections are about 1 ft shorter. The short tubes are required in the southwest quadrant of the furnace where the thermal shield is shortened by the proximity to the curved wall of the containment vessel. Thé U~-tubes in each section are staggered in length by.ul/E in., with the longest U-tube in the center of the array of seven. This arrangement facili- tates insertion of the U-tubes into the thimbles. The electrical input to the reactor furnace heaters is controlled manually in response to indicated temperature readings. There are three controllers, each serving three junction boxes, or sections. The electrical circuits for the power supply to the heaters is described in Section 19.7. The reactor heaters are not connected to the Diesel- driven emergency power sypply. | The annulear space between the reactor furnace and the thermal shield wall is thermally insulated to a built-up thickness of 6 in. with "Careytemp 1600°F" block insulation, covered with 16-gage 304 stainlgss steel sheet, on the side, bottom, and top (see Section 5.6,6.3); : a b Wy N 133 5.4 Fuel Circulation Pump The fuel-salt circulation pump is a centrifugal sump-type pump with an overhung impellér. It is driven by a T5-hp electric motor at ~1160 rpm and has a capacity of about 1200 gpm when operating at a head of 48.5 ft. The 36-in.-diam pump bowl, or tank, in which the pump volute and impellef are located, serves as the surge volume and expansion tank in the primary circulation system. A small tank located beneath the pump and connected to it through an overflow line provides additional volume for expansion of fuel under abnormal conditions. A general description of the pump was given in Section 2.6.2 and Fig. 2.3, which is a simplified cross-sectional drawing of the pump. Figure 5.21 is an exterior view ofrthe pump. The basic data for the pump are summariied in Table 5.5. The general location of the fuel circulation pump and overflow tank within the reactor cell is indi- cated in Figs. 4.4 and 4.5. The sampler-enricher system, which can add or withdraw small quantities of fuel salt from the pump bowl via line 999 is described in Section T and is not included in this discussion of the pump. All parts of the pump in contact with the fuel éalt are fab- ricated of INOR-8, The pump is of a design similar to those used extensively at ORNL for circulation of molten salts and liquid metals. The pump was first tested at simulated reactor conditions of speed, flow and head using water in a circulating loop.60 It was subsequently tested with molten salt at reactor‘éonditions, including thoée'of pressure‘and temperature. - The fuel and cbolant salt pumps‘were maéhinéd and assembled at the machine shops of the Y-12 Plant in Oak Ridge. Castings for the volutes and 1mpellers were made at General Alloys Company (Boston) The ASME dished heads for the pump bowls, or tanks, were fabricated at Lukins Steel Company (Phlladelphia) from INOR-8 material furnished by ORNL. The pump motors were purchased from Westinghouse Electric Corporation (Buffalo). 5 The présSure vessels and the seals needed where the electric leads pass through the vessel, or "can," were obtained by Westinghouse by subcontract with Emil Vondungen Company (Buffalo). Fabrication of the drive motors was covered by ORNL speci- 134 ye! L = H ) 0 a 1 & o Photo 66693 4 {a, Exterior View of Fuel Pump Showing Flange Bolt Exten- Fig. 5.21. sions. *y 135 Table 5.5. Fuel-Salt Circulation Pump Design Data e Design flow: pump outpgp¢ gpm 1200 internal bypaés, gpm | 65 Head at 1200 gpm, ft 418.5 Discharge pressure, psig ~55 Intake pressure, psig av'?' Impeller diameter, in. : 11.5 Speed, rpm 1160 Intake nozzle (sched 40), in. IPS 8 Discharge nozzle (sched 40), in. IPS 5 Pump bowl: diameter, in. %6 height, in, 15 Volumes, £t ’ Minimum starting and normal operating h.1 (including volute) Maximm operating , 5.2 Maximum emergency (includes space above vent) 6.1 Normal gas volume 2.0 Overall height of pump and motor assembly, £t 8.6 Design conditions: pressure, psig 50 | temperature, °F 1300 Motor Rating, hp 7> Supply, v (alternating current) | 480 Sterting (locked rotor) current, amp | 450 Tyfie - ' s . . SBquirrel-cage induction NEMA class I - ‘B~ Lubrication - ~ California Research Corporation NRRG-159 Electrical insulation Class H 'VDesign radiation dosage for | 2 x 1010 + electrical insulation, r , Estimated rediation level, r/nr - 107 Overflow tank volume, £t | 5.k 136 6L , 65 fications. Testing of the completed pumps was performed by personnel of the ORNL Reactor Division. Complete assemblies of motors and rotating parts were provided for four pumps--two for the fuel- salt system and two for the coolant-salt system--in order to have a spare pump on hand for each system. The pressure-containing parts, which include the drive-motor housing, the bearing housing, pump bowl, lubrication reservoir, lubri- cant passage, nozzles, the overflow tank, etc., were all designed in accordance with Section VIII of the ASME Boiler and Pressure Vessel Codeu7 and Code Interpretation Cases 12701\1LL8 and 1273N50 for primary vessels. A lubricating-oil system is required for each pump. The oil- circulation pump, cooler and storage tank, and filter are located in the secondarily shielded tunnel area outside the reactor cell. The lubrication system is described in Section 5.4.1.%, following. In order to prevent salt from getting into the gas and lubricant passages, etc., on too high a level in the pump bowl, an overflow pipe leads to a catch tank located directly beneath the pump. This overflow tank is described in Section 5.4.7. | Other auxiliary systems are the cooling water, which is circulated in a coil around the pump-motor vessel, the cover gas, and the cooling gas, which is directed around the exterior of the upper portion of the pump bowl. The pump is designed to operate at a synchronous speed of ~1160 rpm. If it proves desirable to conduct experiments in the MSRE other than design flow rates, the pump speed can be changed by varying the frequency of the electrical input to the motor through use of a motor-generator set, which can be brought to the MSRE site and operated on a truck-trailer unit. 5.4.1 Description The fuel-salt pump consists of three principal assemblies: (1) the rotary-element assembly, which includes the rotating shaft and impeller, the bearing housing and bearings, the shield block, and the impeller cover plate and upper labyrinth subassembly; (2) the pump bowl, which contains the volute and has inlet and outlet nozzles; and (3) the drive-motor assembly.6 at ¥y 137 The motor can be removed by unbolting it from the bearing-housing upper flange. A splined coupling joins the motor shaft to the pump drive shaft so that the motor can be withdrawn. The fotary-element assembly can be removed by unbolting the lower bearing-housing flange from the pump-bowl flange. Each of the twenty-four bolts in this flange has an extension with universal Jjoints which allow the bolts to be turned with simple socket wrenches with extension handles operated from directly above the unit (see ORNL Dwg. F-RD-9830-F).¥ Both the flanges mentioned above have ring-joint leak-detected closures. All water cooling lines, gas lines, lubricating-oil lines, etc., which serve the removable motor and rotary-element assemblies, have specilal disconnect couplings to facilitate disengagement using remotely operated tooling. 5.4.1.1 Rotary-Element Assembly. The rotary-element assembly consists of the 347 stainless steel bearing housing, which is about 8 in. in dlameter by 23 in. long and has a 29-1/2-in.-diam flange at the upper end and a 23%-in.-diem flange at the lower end. The pump shaft, which is ~3 in. in diameter by 48 in. long, passes through this housing and is supported by ball bearings. The upper bearing is an SKF-T31L7BG angular contact type in a face~to-face duplex configuration which absorbs both radial and thrust forces. The lower bearing is an SK-7219G angular contact type in a back-to-back duplex configuration which absorbs radial forces and provides additional stiffness for the shaft. The impeller is overhung about 22 in. beneath the lower bearing. Both bearings are lubricated and cooled to an operating temperafiuré of about 150°F by a lL-gpm flow of oil supplied through line 703 and leaving via line 706. The lubrication system will be déscribed'subséquently in Section 5.4.1.4. Contact—type seals are located above and below the bearings to confine the oil to the lubrication system. The seals have stationary graphitar rings (U. S. Carbon Company) supported on flexible stain- less steel bellows (Rovertshaw-Fulton Gombany) that bear against case~hardened, low carbofi steel rings mounted on the pump shaft. *0ORNL drawings for the MSRE pumps have a different numbering system than that used for all other MSRE drawings. 138 The seal assemblies were manufactured in the machine shops of the Y-12 Plant in Oak Ridge. The seals are of the balanced-piston type and are designed to operate normally with & pressuré on the lubricant side 2 to 8 psi higher than that in the pump bowl, which is at about 5 psig. Under these conditions the lower seal can accept, without opening, pressure transients in the pump bowl as high as 65 psia or as low as 1 psia. | A catch basin located above the coolant passages in the shield plug (to be described subsequently) collects any lubricant that leaks past the lower shaft seal. This seepage is conveyed from the reactor cell through 1iné 524 to an oil catch tank. The gas that accompanies the oil seepage is disposed of through the off-gas system. The amount of oil leakage, which is estimated to be less than 40 cc/day, can be measured and compared to the reduction of the oil in tpe lubrication system reservoir. At this rate of oil loss the system could operate for more than a year before an o0il addition to the oil 67 reservolr would be necessary. The oil catch tank, however, is limited 90 days storage capacity for the same leak rate. The gas pressure on the lubricant (upper) side of the lower shaft seal is maintained equal to that in the gas space above the‘oil level in the lubrication system reservoir located in the tunnel area by interconnection through the breather pipe (line 590). The gas pressure on the lower side of this seal is that of the helium cover gas in the pump bowl, or normally about 5 psig. Helium gas is introduced into the pump-shaft annulus Jjust below the lower shaft seal through line 516 at a maximum rate of 0.084% scfm. A small part of this gas flows out through line 524 to prevent migration of oil vapor to the fuel salt in the pump bowl; the rémainder flows down the annulus to prevent the migration of radiocactive gases and particulates from the salt region into the lower shaft-seal a.rea68 and sérves as the main flow of sweep gas for removal of fission product gases from the pump bowl. The pressure drop in the gas flow through the pump from line 516 to 524 is about 0.25 in. H, conditions. The offgas system will be described subsequently in Section 12. O at design flow at " 159 An INOR-8 shield block, which is 13 1/2 in. in diameter by ~8 in. thick and has a hole at the center for the pump shaft, is bolted to the bottom of the lower bearing housing flange. This block provides some shielding for the oil in the bearing housing and for the pump motor against irradiatioh by the fuel salt in the pump bowl. It is withdrawn as part of the rotary element assembly. The block is cooled by an 8-gpm flow of oil supplied through line 704 and leaving with the lubricating oil through line 706. The cooling oil flows through grooves 1/4 in. deep by 3/U4 in. wide, spiraling from the % in. to 10 1/2 in. in dismeter on the upper surface of the plug. The estimated heat to be removed to maintain the lower shaft seal temperature to an acceptable value is about 18,000 Btu/hr.69 The 11.5-~in.-diam impeller is keyed to the lower end of the INOR 8 pump shaft and retained by a bolt tack welded in place. A slinger ring is located on the shaft Jjust above the impeller. The pump shaft speed is sensed continuously with a magnetic reluctance pickup (Electro Point 721280) utilizing an interrupter gear that is integral with the lower portion of the shaft coupling (see ORNL Dwg. F-983%0-62). The output of this pickup (SI FP-E) is transmitted to a speed indicator, the control circuit and alarm system, and to the data logger. The direction of rotation can also be sensed by the pickup. Labyrinth-type seals are used on the impeller inlet shroud (lower labyrinth) and on the impeller support shroud (upper labyrinth) as shown in Fig. 5.22. The upper labyrinth is integral with the impeller cover plate, which is sealed to the volute with a 1/4-in. OD INOR-8 O-ring about 12.75 in. ID. Labyrinth seals are also pro- vided on the shaft at each of the aforementioned contact seal assemblies. 5.4.1.2 Pump Bowl. The pump bowl, or tank, is about 36 in. in diameter and 17 in. high at the centerline. It is formed of two INOR-8 ASME dished heads with a wall thickness of 1/2 in. The normal fuel salt level in the bowl is about 11 in. from the bottom, measured at the centerline. The pump volute is an Allis-Chalmers 8- by 6-in. Type SSE (Allis- Chalmers Dwg. 52-423-L98) with 5/8-in. wall thickness. The 8-in.-IPS —OI"—O.OSO UNCLASSIFIED ORNL-DWG. 6§4-6902 BRIDGE ) TUBE — PUMP VOLUTE A UPPER LABYRINTH IMPELLER N COVER PLATE A SLINGER 3 TOP EDGE IMPELLER E‘. - OF IMPELLER R PUMP BOWL -~ \ DISCHARGE NOZZLE ,,jq,’ DISCHARGE ' SHAFT e VOLUTE 7 - 0.250 - CLEARANCE BAFFLE T B PUMP BOWL WALL S #— IMPELLER INLET SHROUD — VOLUTE W DISCHARGE 0.02% | LOWER LABYRINTH (a) CLEARANCES AT IMPELLER SEALS (b) BRIDGE FIG.5.22. FUEL-SALT PUMP BRIDGE AND IMPELLER SEAL CLEARANCES DISCHARGE TUBE o7t *y 141 sched-40 inlet nozzle on the bottom of the bowl is concentric with the centerline of the pump. The volute entry nozzle and the impelier' inlet opening are also 8 in. in diameter. The pump discharge from the volute is through a special thimble, 5 in. ID by 7 in. long, having spherically shaped ends. (See ORNL Dwg. D-2-02-054-10065-A). spherical portions fit into similarly shaped seats in the volute and in the pump-bowl discharge nozzle (see Fig. 5.22). This bridge tube provides the flexibility needed to absorb the three-dimensional relative motions between the volute and the bowl and at the same time allows only a small bypass flow through the Jjoints back into the pump bowl.. A second bypass flow, called the "fountain flow, " escapes through the clearance between the top side of the impeller and the pump casing, and thence through the clearance between the pump shaft and the pressure breakdown bushing. With the clearances shown in Fig. 5.22, the fountain flow is estimated to be about 15 gpm (ref 60, p 27). A third bypass flow, termed the "stripper flow," of about 60 gpm is taken from the pump-bowl discharge nozzle into a ring of 2-in.-diam pipe encircling the vapor epace inside the pump bowl on a radius of about 15-1/2 in. This distributor has regularly spaced holes, half about 1/16 in. and half 1/8 in. in diemeter, oriented about 30° from the horizontal and pointing downward toward the center of the pump bowl. The holes are about 1 in. above the normal fuel-salt level in the bowl. The bypass filow is: sprayed from these holes into the bowl to promote the release of fission product gases to the vapor space. The.efficiency of this stripping action is. estimated to be sufficient to reduce the 15%e poison level in the reactor to less that 2% in Ak/k. The in- fluence of residence-time dégtribution on fission product decay in the pump'bowl was-investigated, and the efficiency of ‘Xenon removal and the effectiveness of the purge gas system were studied prior to completion of the pump design. mn gas in the pump discharge (line 101) during preoperational filling of the system with molten salt., This gas, after venting into the bowl, is withdrawn through line 521. »12 The same spray holes serve as vents for the 142 The bypass flows circulate downward through the pump bowl and re- enter the impeller. The spray entrains a considerable volume of cover gas in the liquid, and the tendency for this entrainment to enter the pump is largely controlled by a baffle on the volute. Tests indicated that the liquid returning to the impeller will contain 1 to 2 vol % of gas. A 1-1/2-in. vertical sched-40 nozzle is provided at the top of the pump bowl to allow a capsule to be lowered into the salt in the bowl to take a sample or to add small amounts of enriched fuel. A cap- sule guide and latch stop inside the pump bowl positiofis the sample capsule.sg The sam@ler-énricher system is described in Section 7. The liquid ievel in the pump bowl is sensed by bubbler-type probes. One of the 1/2-in.-IPS bubbler tubes (line 596) extends about 3-7/8 in. below the centerline of the pump volute, or a min. of 6-1/8 in. below the salt level in the bowl. The other (line 593) extends to about 1-15/16 in. below the centerline of the volute. A third 1/2-in. connection (line 592) at the top of the pump bowl provides the reference pressure as helium gas 1is bubbled through the two tubes. Through previous cali- bration, the helium pressures can be converted to liquid level; also the difference in pressure between the two probes at different levels may possibly be translated into approximate salt densities. The bubbler system is further described in Section 10.9.1. A pump-bowl overflow pipe (line 520) releases salt to the overflow tank in event the salt level in the circulation system becomes too high.75 The lower portion of the pump bowl is cooled by the flow of fuel salt. Above the liquid level, however, heat produced at a rate of about 15 kw through beta and gamma absorptions would tend to overheat the metal and would cause undesirably high thermal stresses unless cooling is provided. The top portion of the bowl is fitted with a shroud that is spun from 305 stainless steel and is about 38 in. in diameter; a space 1/4 in. to 1 in. wide is provided between the shroud and the pump-bowl surface through which cooling gas can be direéted (see ORNL Dwg. E-47296). The estimated quantity of cooling gas (95% N, 5% 02) required is about 400 cfm (S’.T.‘P).'_(J+ %y 143 5.4.1.3 Drive Motor. The pump drive motor is a Westinghouse totally enclosed, water-cooled, explosion~proof, NEMA Design "B," speclal-purpose, squirrel-cagé induction motor of_75-Hp capacity. It is rated at 480 v and normelly has a starting (locked rotor) current demand of 450 amp. The starting torque is slightly less than 135% of full-load torgue, and the pull-out torque is slightly less than 200% of the full-load torque. It is planned that the motor will normally run at synchronous speed of ~M160 rpm. Operation at different speeds can be obtained by varying the frequency of the electric power supply through use of & motor-generator set which can be brought to the MSRE site. The drive motor is directly connected to the pump shaft through a modified flexible coupling (Thomas Flexible Coupling Company Cat. No. 263 DBZ; also see ORNL Dwg. D-2-02-054-9848). This type of coupling does not require lubrication. The motor shaft is splined to slip into the coupling to facilitate removal of the motor. | The electrical insulation used in the motor is Class "H", designed for 150°F ambient conditions and & radiation dosage of 2 x 107 r before mechanical breakdown and a total dosage of 2 x lOlO r before electrical breakdown!” (also, see ref 66, p 52). The background radiation in the region of the pump motor was estimated to be in the order of lO5 u rad/hr.76 A three-conductor, mineral-insulated, copper-covered cable connects the motor to a three-prong plug‘that can be inserted into a receptacle by a remotely operated manipulator tool of the type described in Section 19.7.5. ‘The electrical lead seal through the pressureétight mptoffhousing is a ceramic type. = 8 | ' vThé motor housing, or can, is surrounded by a water coil through which abOut'S-gpm'of,tfeated, demineralized water is introduced through the 1-in.'sched-40 pipe (line 830) and leaves through line 83. The 11/16-in. OD x 1/16-in. wall thickness stainless steel tubing is heliarc welded to the can using stalnless steel filler rod. The lower end of the motor casing is flanged and is bolted to the top flange of the béaring-houSihg assembly by use of a ring-joint leak- detected type of closure. The motor casing is fabricated of ASTM A-201 Grade A carbon steel to meet the requirements of the ASME Boiler and 144 | 4 Pressure Vessel Codeh7 and must pass a mass spectrometer leak test with “? a leak rate of less than 1 x 10~8 cc of helium per second (STP). | 5.4.1.4 Lubricating-0il System. The oil system serves te lubri- cate and cool the pump bearings and to cool the ghield plug located between the bearings and the pump bowl. The fuel-salt pump and the coolant salt pump have separate lubricating-oil systems, but they are intercon- nected so that one system could Serve both pumps in an emergency situation. Each lubricating-oil system consists basically of a water-cooled oil reservoir, two centrifugal pumps connected in parallel, and an oil filter as shown in the lubrication system flowsheet, Fig. 5.23 (ORNL Dwg. D-AA- A-40885). The equipment is located in the east tunnel (see Fig. 4.4), which is a secondarily shielded area. The design data for the lubrication system are presented in Table 5.6. The lubricating oil is a turbine-grade, paraffinic base, 100% straight mineral oil having a viscosity at 100°F of 66 SSU. Other lubricating-oil properties are shown in Table 5.7. The lubricating- oil specifications are discussed in reference 77. Investigation of the o0il temperature after cessation of the oil flow in an accidental situation determined that the temperature.would not exceed about 500°F, the approximate condition at which oil damage would become appreciable, until about 10 min after the oil flow stopped.78 The oil reservoir is a carbon steel tank, 22 in. in diameter by 32 in. high, with ASME dished heads 1/4 in. thick. The tank is surrounded by eight turns of a water-cooled coil of 1l-in.-diam copper tubing. The ' required water flow rate is about 10 gpm of 85°F water. The -inside surface of the tank is provided with passageways, about 2 in. by 3/8 in., | = to direct a 50-gpm bypass flow of oil from the pump against the tank wall at an average velocity of about 21 fps. The overall heat-transfer coefficient is estimated at 230 Btu/hr-ft2—°F, and the maximum heat- removal rate at 41,000 Btu/hr (see ref 66, p 57). The oil reservoir is provided with a liquid-level indication, LI-OTI, the output of which is fed to the data logger and the slarm system., In event of a drop in oil level, indicating an oil leak past the lower shaft seal of the pump, the flow controi valve FSV-T703 auto~ | matically stops the flow of oil to the pump. Alarms are also provided ‘EJ A ~ 145 A e < D B jl ” - - : - | LUBRICATING Ol (NT— (733) 1-40-8 BREATHER COMBECTION-— (ggg i SHIELD COOLANY OIL IN— !'{rofl S I—Tuae & ICOOLANT dbuss) - o 12 OPM AT 130 *F—, i-40-§ =~y oIL w'p..} 158 —t p—A—A A ————F# 4 2 . MATCH | LINES ARE QUICK DISCONNECT Y T ‘ TO Ol HAND PumP SYSTEM ONLY F——_— xVTI M' LTURN OIL TERCONNECT| ION CONNECTING LINES SUPPLY OIL IN RCMCTIG‘ 70 OIL SYSTEM FOR COOLANT PUMP (5108) ysi3a cvmis L~ HELI FRN LONE 10 (B35~ I - x N N ] VALVE C— —— une seo m CHECK LUBE Ol PACKAGE . onm cr:u. . s 9 SERVICE TUNNEL ¥ z ‘r"'—l-flo-‘ OIL SUPPLY TANK DATA & z & Ve wavERiAlL __camson sTeer § - g o —p—> HEIGHT 32 ‘ . 0o, 22 | ‘ BESIGN PRES: re : g “"‘" DESION_TEMPERATURE 200°F b roa) <] . OPERATING YOLUME 22 BAL, : vre2C LINE BLOWOUT COOLING TY & ; QUICK DISCONNECTS p ‘ . e ' V704 2-40-! (763) P T4 ’ | (764) vyvre [ (822} 2 OIL FILTER OF1 I E— et QUICK DISCONNECT CONNECTION . NOTE : WATER OUT (vee2) @—N——T0 PORTABLE CONTAINER ; L CINING TOWER o '3740 5™ 3 1.FUEL AND COOLANT PUMP OIL SYSTEMS ARE IDENTICAL EXCEPT FOR LINE AND EQUIPMENT NUMBERS. COOLANT SYSTEM NUMBERS ARE SHOWN IN PARENTHES!S. _2_ALL LEAK DETECTION FOR LUBE OIL SYSTEM | | 13-40-8 1S LOCAL. TUBING 15 NOT CONNECTED TO THE REMOTE LD SYSTEM IN THE TRANSMITTER WATER IN veZtA N (vB23m) (vezsa} (FIA 23 ’ 5. THIS DRAWING REFLECTS i AS BUILT COOLING_WATER SYSTEM loaa-a-a0any ’ : , DIL SYSTEM FOR FUEL PUMP INSTRUMENT ] ‘ i CHANGES APPLICATION DIAGRAM D-As-A-40504 " oATE _9-22-64 | [ COOLANT SYSTEM D-AA-A-4088¢ ] ! FUEL SYSTEM DAA-A-408 80 m % P i LT, -, OAK RIDOE NATIONAL LABORATORY \» /W(o- L] > 28\, i e [0 v TA iR © B AT LANT PUMPS [T2956 | C | SEE PEN 2930 » hlelioms e M.S.R.E T 8 | SEE DCN_ 266! 4 /L owtn = . 2 M. a9 T Loz pow pasi (oG )TN Dam W + NONE s0m 4330 | |o-aa-a-40888-c n s c o T " TING DEIGN 18 THE PROPERTY OF UMON CARMMOR NUCLEAR COMPANY = DIVISION OF UinbN CARIMDE CORPORATION ‘.1‘:';""‘""..2 FIGURE 5.23 __ 146 Table 5.6. Lubricating-0il System Design Data ‘01l supply temperature, °F 140°F 0il flow to pump bearings, gpm L Coolant oil flow to shield plug, gpm 8 0il seepage through shaft seals (max), cc/day 40 Outside dimensions lube oil package (1 x wxh), in. 100 x 34 x 50 Estimated weight, empty, lb. 2200 0il reservoir | Operating volume, gal | 22 Total volume, gal 43 Volume of oil in system, gal 3l Tank height, in. 32 Tank outside diamefer, in. 22 | Material ASME SA-201 Grade A carbon steel Allowable stress, psig 13,750 Design pressure, psig | 75 Design temperature, °F 200 Heat removal capacity, Btu/hr 41,000 0il circulating pumps (2) (Allis-Chalmers 2 x 1.5, Type MH) Capacity of each, at 160 ft head, gpm 60 Motor (Type TENV Frame CMK-718), hp 5 Power input (rated), kw at 220 v 5.25 Speed, rpm, and impeller diam, in. 3500, 6-5/8 in. Design pressure, psig ' 210 Design temperature, °F 225 0il filter Type Cuno EFS Size, in. " 2-1/h by 8 Material Carbon steel Residence times In reactor cell, sec 18 In coolant cell, sec 15 -3 » & © - 147 for high oll temperature, low oil flow rates, or high lube oil pump motor temperature. | A blanket of helium gas is maintained over the oil in the reservoir tank. The helium supply line (1ine 513) and the off-gas vent (line 535) are provided with pressure-control valves (PCV-513 A-1 and A-2) to maintain the gas pressure at about 7 psig. The gas flow rate is essentially zero. The top of the oil reservolr tank is vented to the bearing housing on the fuel pump through line 590. The helium pressure above the salt in the pump bowl is about 5 psig. Two 5-hp Allis-Chalmers "Electric-Cand" centrifugal oil pumps, 2x1,5, type MH, are connected in‘parallel, either one of which has sufficient capacity if used alone. The pump motor is cooled by a small internal by-pass oil stream. About 50 gpm of the pump output is returned to the oil reservoir as a bypass flow to promote heat transfer at the tank wall. The oil filter is a standard Cuno EFS filter using carbon steel filter elements. Radiation monitors (RIA-OTI) are located in each lubrication system to detect contamination of the oil or the blanket helium gas, The 1ubricating-dil system equipment is compactly arranged into a "package" which can be conveniently shielded with lead bricks. The valves have extension handles passing through the lead shield. Sampling nozzles are located on oil lines external to the package for periodic sampling of the oil for both radiation and thermal damage. 5.4.1.5 0il Catch Tank. Lubricating oil seeping past the lover shaft seal of the pump is pipe& from the reactor cell through 1/2-in. line 524 to an oil catch.tank located in the special equipment room. The portion of the line inside the reactor cell is shielded to reduce the amount of induced activity in the oil. ?he catch tank is fabri- cated of a 46-1/2-in.-long section of 2-in. sched-40 pipe topped by & 20-in.-long section of 8-in. sched-40 pipe. The top portion catcheé gross leakage while the lower portion, holding 0.7 gal, pro- vides sensitivity for a level indicator, LIA-524., This level instru- ment, and those on the lubricating-oil supply tanks, provide for close inventory of the lubricating oil. Details of the tank are shown on ORNL Dwg. E-GG-C-41518. Table 5.7. 148 Lubricating 0il Properties Nature of base oil Type of base oil Gravity, API Viscosity SSU at 100°F, sec 8sU at 210°F, sec Flashpoint, °F Firepoint, °F Thermal conductivity, Btu-ft/ftZ-hr-°F Heat capacity, Btu/1lb-°F Specific gravity Equivalent grade Y-12 Plant Equivalent commercial grade (UCNC) 100% straight mineral Paraffinic 34.8 66 36 320 34T 0.076 0.45 0.85 Turbine oil, Gulfspin 35 Code DJ by 4‘11 149 The rate of oil loss from the system is estimated to be less than 40 cc/day.67 In event the oil catch tank cannot hold the accumu- lated oil for a satisfactory operating period, a 55-gal stainless steel drum is provided in the coolant drain cell to which the catch tank can be drained through line 720 during reactor shutdown. This drum may vent through the valve to the off-gas system through line 525 during draining. A small amount of helium gas leaves the pump with the oil. A capillary flow restrictor in the gas line downstream of the oil ecatch tank limits the flow to less than 0.07 liters/min. This restrictor is preceded by a sintered disc filter, and followed by a flow indicator, FIA-52Lk, Line 524 continues as l/2-in. pipe through the coolant salt drain cell to the vent house instrument box. The gas is vented through the off-gas system described in Section 12 following. 5.4.2 Hydraulics The MSRE fuel-salt pump has an 8-in. by 6-in. volute-impeller combination. These sizes were selected on the basis that this provided a reasonable hydraulic capability and were sufficiently standard so that existing patterns could be used in making the INOR-8 impeller and volute castings. Hydraulic performance data were determined on prototype pumps over a wide range of flow and head conditions and at several speeds, using 1l1-in.- and 13%-in.-diam impellers.6o A design pump speed of 1150 rpm was selected, and the impeller diameter was established as 11-1/2 in. The hydraulic performance data are summarized in Fig. 52k. It may be noted that at the design speéd of 1150 rpm and design flow rate of 1200 gpm the developed head is 48.3 ft. The pump efficiency under these conditions is 80-85%. The flow startup times for the primary circulation system were estimated using assumed motor accelerating torques (which are nearly constant up to about 60% of speed), and it was found that 50% of full flow is attained after about 3/4 sec, 75% after 1-1/4 sec, 90% after 1-3/4 sec, and 100% is reached in about 3 sec. ” H ,TOTAL HEAD (ft) 60 50 40 30 20 150 ¥ UNCLASSIFIED ORNL-DWG 64-3398 R IMPELLER DIAM: 11Y; in. CONSTANT MOLTEN-SALT TEMPERATURE: 1200°F ~¢ RESlSTANCE‘ \.. \ /, \. - \\450 - 7( / sl rpm y - o L Ty \ ’ -~ /41030 s 7/ ~e y / /‘ ™ o —— \‘l / 860 / T~ 7 Z ~ - —— “ \ ) —— .< . ./ A7~ < / P~ 4 ~ - /‘ e 800 P “;o/ ~ PUMP HYDRAULIC T ™~ BALANCE LINE - . 200 400 €00 800 1000 1200 1400 1600 s a, FLOW RATE {gpm) Figure 5.24. Hydraulic Performance of Fuel Pump. iy e i 151 Coastdown tests determined that about 10 sec are required for the pump motor tb stop after the electrical supply is interrupted (seev ref 80 p 47 and ref 60 p 31). Tests of the prototype pump (with 13-in,-diam impeller) indicated that when the liquid level in the pump was lowered to h-l/Elin. below the centerline of the volute, increased amounts of entrained‘gas were present in the pump discharge. At about 5-1/2 in. below the volute centerline, the-system flow was cut about in half; and at 6-1/2 in., the flow was reduced essentially to zero (ref 60, p 31). The prerotation baffle shown in Fig. 2.3 at the pump inlet has the effect of increasing the head at the lower range of flows when operating at a constant speed (ref 60, p 15). At the most efficient operating conditions, when the various losses in the impeller and volute are at a minimum, the pressure distribution in the volute is essentially uniform, and the net radial force on the impeller is near zero. When operating at higher or lower flow rates at the same pump speed, the volute pressure distribution becomes non- uniform and produces a radial force on the impeller and a resulting deflection of the shaft. (The impeller is overhung about 22 in; below the lower bearing.) Tests of the prototype MSRE fuel pump indicated that a running clearance of 0.025 in. in the lower labyrinth (see Fig. 5.22) would provide for all reasonably anticipated conditions of "off- design'" operation of the pump.81 5.k.3 Mechanical-Design.Considerétions Design of the rotary elements involved computation of shaft siresses, deflections, natural frequendy, bearing life éXpectancy, flange bolting requirements, etc. Design of the pump bowl, or tank, required calcu- lation of the wall thickness,'stresseé,'the'flange requirements, and the reinforcement needed at noZzleé,'etc;"‘ | ~ 5.4.3.1 Volute and Impellers. The maximum stress in the volute will be at shutoff flow conditions at 1160 rpm and is estimated to be 2560 péi'ifi bending (ref 66, p 21):7 The maximum impeller stress is at the keyways and is estimated to be about 2000 psi. 5.4.3,2 Shaft. The impeller horsepower at rated conditions is 47.5 hp, based on a pump efficiency of 80% and a pump speed of 1150 - Vi 152 rpm. Assuming a radial thrust on the impeller of l95,lbf (see Section 5.4.2), the net axial thrust is 1130 b, downward. Some of the calcu- lated stresses are summarized in Table 5.8 (ref 66, pp 28-30). The maximum shaft deflection at the end of the impeller was esti- mated to be 0.0110 in., based on the above-mentioned radial thrust (ref 66, p 31). The natural frequency of the shaft was predicted to be at 2850 rpm, which is well above the design operating speed of 1160 rpm (ref 55, p 33). 5.4.3.3 Bearings. The SKF catalog data were adjusted for MSRE " operating conditions, and a 1life expectancy of 300,000 to 500,000 hr for t the pump bearings was predicted (ref 66, p 32). 5.4.3.4 Pump Bowl and Nozzles. Using standard equations from the ASME Boiler and Pressure Vessel Code, Section VIII,lLS the wall thickness tr required for the pump-bowl ASME torispherical heads was determined to be 0.438 in.; based on an allowable stress for the INOR-8 of 3600 psi. The actual thickness used is 1/2 in. (ref 66, pp 16-21). A reinforced area is provided at the 8-in. suction-nozzle opening to provide material in excess of 140% of that needed to maintain the stresses within the allowable limits. The 1-1/2-in. sched-40 fuel- sampling-enricher nozzle is also reinforced. The discharge nozzle requires an elliptical opening 6 in. by 7 in. The weld fillet in the knuckle region at this nozzle is enlarged to provide some excess re- inforcement. The upper nozzle is 13.625 in. ID and does not require ‘ extra reinforcement (ref 66, pp 16-21). . The stress in the pump bowl due to the discharge nozzle reaction & wag determined to be of little concern. The stress in the 23%-in.-diam pump-bowl flange, which is designed for 50 psi and 300°F, were found to be about 13,290 psi, using standard methods of combining stresses (ref 66, p 23). Stresses in the pump bowl due to axial loading only were analyzed and found to be about 5000 psi.82 The bearing-housing upper flange, which is 27—1/2 in. -in diameter and has an assumed operating temperature of 150°F, has calculated stresses of 14,720 psi (ref 66, p 34). “y 2 153 Table 5.8. Estimated Stresses in MSRE Fuel-Pump Shaf (psi) Sheer stress in lugs of impeller stud Tensile stress in threaded portion of impeller stud Shear stress from combined bending and torque at lower bearing Torsional shear stress in shaft at impeller hub Shear stress in keys Bearing stress at keys Shear stress in shaft at plane through bottom of ‘bore in end of shaft ‘ Stress in spline at motor end of shaft 2270 3380 1420 2325 1340 2680 1730 55 o 13 154 5.4.4 Thermal-Stress Design Considerations The MSRE fuel pump is subjected to relatively high thermal stresses at operating conditions because nuclear heating can raise the tempera- ture of some parts above the 1225°F inlet éalt temperature and because of the relatively large temperature gradient between these parts and, say, the top flange of the pump, which is only at about 180°F. The eyclic nature of these stresses as the reactor power level is varied requires that they be evaluated on a strain - fatigue basis to determine the extent of relief that can be expected due to thermal.relaxation in . the materials. , The temperature distributions in the pump bowl were calculated for various conditions of reactor power, salt temperature, and cooling-gas flow over the outside top portion of the bowl, using the Generalized Heat Conduction Code (G-H.T)85 (see also ref 66, p 36). The thermal- stress distributions were calculated for heatup from room temperature to 1200°F, power changes from zero to 10 Mw, and loss of cooling gas, using the general procedures of Stanek.8)+’85 and Witt86’87. In these studies it was assumed that the MSRE would undergo one hundred heatup cycles and five hundred power-change cycles. It was further assumed the allowable number of cycles as determined from the fatigue curves for INOR-8 should exceed the anticipated number of cycles by a factor of at least 1.25. The estimated thermal-fatigue life was found to be adéquate, and the calculation indicated that the cooling-gas flow rates could be varied over a broad range with small effect.88 (See also ref 66, p 37) . The sampler-enricher connection line (line 999) to the fuel pump bowl is subjected to thermal stresses due to the axlal temperature gradient in the line and also to the pump movements caused by the thermal expansions in the primary circulation system. The stresses caused by the piping reactions in the sampler line were estimated to be 7580 psi in bending and 1940 psi in shear. These stresses fiere combined with the pipe reaction stresses and compared to the strain-cycle data. A usage factor of 0.367 was obtained, which provides a margin of safety greater than two when compared to the maximum permissible value of 0.8 89 o for the usage factor. Ry ax 155 5.4.5 Pump Supports To provide the flexibility needed in the primary-circulation-system piping to maintain the stresses within the allowable limits, it is necessary that the heat exchanger and the fuel-salt pump be allowed to move in certain directions as the system is heated. (The reactor is fixed in position and an anchor poinf for the piping.) Because of the degrees of freedom needed, and the amount of expected movemenfi, the fuel-pump support equipment is relatively complicated (see Fig. 5.25). The fuel pump is bolted to a 2-1/2-in.-thick plate that is mounted on two sets of 2-in.-diam rollers, allowing the pump to move in a horizontal plane. (See ORNL Dwgs. E-CC-C-41L450 and D-CC-C-41511). The rollers travel on a spring-supported'parallel-link framework that permits the pump to rise vertically from the cold to the hot position. ‘The pump is restrained from rotation about any axis. Three 3-3/k-in.- diam by 4-in. stainless steel, NaK-filled, double bellows, with orificé plates betwéen the bellows, act to dampen the vibrations induced by the pump-shaft rotation. The entire pump assembly is carried by two 8-in. horizontal I-beams. 20 When the primary system is brought up to operating temperature, the pump moves about 0.4 in. horizontally in the north-south direction,91 about 0.3 in. in the east-west direction, and about 0.8 in. vertically. As stated above, there is no rotation of the pump assembly, 5.4.6 Heaters The lower half of the pump bowl, & 3-ft-long section of suction piping and thé S:in.790° bend at the*bbttom of the piping section, and the overflow tank are all heated in a common furnace, which is about 51 in. OD by 66 in. high. - o The heatlng elements are. 3/#-1n ~diam straight tubes of 304 stain- less steel, contalning ceramic p051t10ned re51stance heating elements at the lower ends and having the trade name "Firerod" (Watlow Manu- factufing Company). Five of the rods are abofit 84ft long overall, with a heated length of about 5 ft, which extend all the way from the terminal boxes to the bottom of the basket. Nine of the rods are about 7 ft long with a heated length of 4 ft. The heater rods slide 96T Figure 5.25. Fuel Pump Support %4 a » 157 into 1-in.0D 304 stainless steel tubes (0.065 in. wall thickness). (See ORNL Dwg. E-MM-B-51604). The long and short heater rod are arranged, with but one exception, into removable assemblies of one long rod and two short ones. Each of these groups of three rods has a terminal box, or housing, at the upper end which has a lifting ball, and in which the electrical power and thermocouple connections are made at a terminal block. The nine shorter heater rods, called the "upper portion," are connected as one electrical circuit and have a total heating capacity of 6.5 kw. The five long rods, or "lower portion," are another circuit and have a capacity of 12 kw. The 51-1/2-in.-OD furnace has & 5-in.-thick layer of‘"Careytemp 1600°F" block insulation (Philip Carey Manufacturing Company), covered with 20-gage 304 stainlese steel sheet, The bottom of the furnace is similarly insulated and covered. The top insulation is 2-1/2 in, of "Fiberfrax" blanket, "Type XIM," and is also covered with stainless steel sheet. The top of the insulated portion of the basket is Just below the bottom of the cooling-gas shroud on the top half of the pump bowl. Gas for cooling the overflow tank can be supplied through a pipe at the bottom of the furnace although such cooling should not be necessary. Supports for the tanks pass through insulated sleeves and bellows in the bottom also. (See ORNL Dwg., E-MM-B-51606). The furnace is suspended from the fuel-pump support plate and moves with the pump. The heater rods have collars which also rest on the support plate. | The terminal box for therthrée rods in each group is connected by three No. 12 wires with insulating beading to a 30-a, 600-v, 3-pole male_plug provided with g 1lifting bail. This plug can be pulled upward by remotely operated tools from the female unit located on the support structure to disconnect the heater wiring for removal of & heater unit or for other maintenance 0pérations. Thé power input to eéch heater circuit is manually controlled in response to the temperature-indicat- ing instrumentation. - The heater control circuits are described in Section 19. Hh 158 5.4.7 Fuel-Pump Overflow Tank Abnormally high salt levels in the fuel-pump bowl might result from ¥y, overfilling, from temperature excursions while operating, or from un- usually high gas entraimment in the circulating salt. An overflow pipe and catch tank prevent the salt level from becoming high enough to allow salt to enter the gas and lubricant passages of the pump. 5.4.7.1 Overflow Pipe. The overflow line is a 1-1/2-in. sched-40 INOR-8 pipe passing through the bottom of the pump bowl and extending @ to 1-1/2 in. above the normal operating level in the bowl, i.e., to an elevation of about 840 ft 3 in. The pipe extends downward from the bowl, A as line 520, and makes three turns in a coil about 29 in. in diameter « before entering the overflow tank located directly beneath the pump bowl (see ORNL Dwg. E-CC-C-56419). The line is contained entirely . within the pump furnace and does not require a heating Jjacket. 5.4.7.2 Overflow Tank. The overflow tank is a torus-like vessel surrounding the tapered section of the pump intake pipe. It is located entirely within the pump furnace, but is not structurally connected to it. The tank is 30 in. OD x 18 in. ID x 27-3/% in. high overall. The tank wall thickness is 1/2 in., and the annular space between the straight walls of the cylindrical portion is 5 in. wide. The ends are closed with heads dished to a 2.5 in. radius, as shown on ORNL Dwg. D-CC-C-56418. The salt storage volume is 5.4 £t-, The INOR-8 vessel ‘ is designed for a pressure of 50 psig at 1400°F and in accordance with . the ASME Unfired Pressure Vessel CodeuT and Cases 1270N-5h8 and 12738-7"°. : The overflow pipe (line 520) enters the top of the tank and dips to within less than 1/2 in. of the bottom. A 1/2-in.-deep dimple is pressed in the lower tank head at the exit opening of the overflow pipe to permit more complete removal of the tank contents. The liquid level in the tank is measured by two helium bubbler lines and one reference pressure line in an arrangement similar to that used in the pump bowl. Helium is supplied through lines 599 and 600 in 1/k in.-0D tubing enclosed in 1/2-in. sched-40 pipe, the tubing Q;Q terminating about 15 in. from the overflow tank with the flow continuing 5 LY Fig. 5.26. Fuel Pump Overflow Tank. Unclassified Photo 70698 66T 160 in the pipe. As in the pump bowl,.the helium supply lines have a surge volume inside and at the top of the tank in the form of a curved portion of 1-1/2-in. pipe. This volume would prevent salt from backing up into unheated portions of the helium supply lines in event of a pressure surge in the salt system. The helium bubbler lines dip to within about 1/2 in. of the bottom of the tank. | The top of the overflow tank is vented to the bff-gas system through & 1/2-in. sched-40 pipe connection, line 523. A 1/4-in.-OD tubing con- ” nection (1ine 589) is made to line 523 to provide the reference pressure for the bubbler liquid-level indication. Line 523 continues through the control valve HCV-523, which can be closed to pressurize the over- flow tank with helium to force the fuel salt from the tank back to the fuel-pump bowl through line 520. Normally, valve HCV-523 1s open to vent the gases from the upper portion of the overflow tank. Line 523 joins the off-gas line 521 from the fuel-pump bowl upstream of the holdup volume in the reactor cell. 5.4.7.3 Tank Support. The overflow tank is located directly beneath the fuel-pump bowl. Three l/2-in.-diam rods with clevis ends suspend the tank from the pump support during initial installation or maintenance operations. Normally, these rods carry no load, and the tank is supported from below by a flat plate mounted on the lower end of three l-in.-diam 304 stainless steel rods. The plate rests on three spring-mounted balls (Mathews Conveyers Company, Type 501) which allow the tank to move laterally in any direction. While connected to the fuel pump only through the overflow line, there may be some displace- ment forces as the pump shifts position with temperature changes. The overflow tank remains at a fixed elevation, the flexibility of the over- flow pipe accommodating the 0.8-in. vertical displacement of the fuel- pump bowl with temperature changes (see ORNL Dwg. D-CC-C-56420). The three l-in.-diam stainless steel support rods mentioned above pass through the pump furnace insulation through corrugated stainless steel bellows welded to the rods at the top of the bellows and with the bottom of the bellows welded to the furnace casing. The clearance between the rods and the furnace bottom allows for relative movement of the tank within the furnace, and the bellows prevent the chimney effect from inducing a flow of cell atmosphere gas through the furnace. o w b o ? ® ok ] 16l If the overflow tank must store a large amount of fuel salt that has a relatively high internal-heat-generation rate, it may be necessary to cool the overflow tank. A 1-1/2-in. connection is provided at the furnace bottom through which cell atmosphere gas can be supplied from the component cooling system. A 3-in.-diam stainless steel bellows in this connection provides a spring-loading on a sliding metal-to-metal flat-plate Jjoint to allow relative movement of the furnace and the gas supply line connection (see ORNL E-CC-C-56419). -5 h 162 5.5 TFuel Heat Exchanger ’a The fuel heat exchanger is used to transfer heat from the fuel salt to the coolant salt. The location of the exchanger in the reactor containment vessel is shown in Figs. 4.4 and 4.5. The relationship of the heat exchanger in the primary system flowsheet is discussed in the preceding Section 5.2 and shown in Fig. 4.6. The physical prop- erties of the fuel and coolant salts are summarized in Table 2.1. With the exception of the furnace-brazing of the tube-to-tubesheet joints, the heat exchanger was fabricated in the machine shops of the v Y-12 Plant. The furnace-brazing was performed at the Wall Colmonoy 2 Company (Detroit). All this work was covered by ORNL specifications.2?95:%% 5.5.1 Description LH] The heat exchanger is a horizontal, shell and U-tube type, with the fuel salt circulating in the shell and the coolant salt in the tubes (see Figs. 2.4 and 5.27). It is of all-welded construction and is fabricated of INOR-8 throughout, except for the back-braze alioy used in the tubesheet Jjoints. The overall dimensions and'design data are given in Table 5.9. (See ORNL Dwg. D-EE-Z-40850) . The shell is ~16 in. OD and about 8 ft 3 in. -long, including the 8-3/h-in.-long coolant salt header and the ASME flanged and dished heads at the ends (see ORNL Dwg. D-EE-A-40874). The shell is 1/2 in. ¢ thick in both the cylindrical portion and the heads. The fuel enters & at the U-bend end of the shell through a 5-in. sched-40 nozzle, near the top of the dished head. A 1/hk-in.-thick baffle on the inside prevents direct impingement on the tubes. The fuel salt leaves through a 7-in.-x B 5 in. reducer nozzle at the bottom of the shell at the tube-sheet end. To prevent vibration at the higher flow rates due to the clearance between the tubes and the baffle plates, INOR-8 rods, 0.166-in. x 1/4-in., are inserted, or "laced", between the tubes. The rods are used at each baffle plate, with one set inserted in the horizontal direction and the other at an angle of 60°. The rods fit snugly into the spaces between the tubes and effectively restrain each tube from transverse motion relative to the others. The horizontal v rods are tack welded in place at each end. The inclined rods are tack ' ‘Ej welded at least on one end, and on both ends where accessible. The 163 e Primary Heat Exchanger Subassemblies. Fig. 5.27. w 164 b Table 5.9. Design Data for Primary Heat Exchanger ‘Efi Th, Construction material Heat load, MW Shell-side fluid Tube-side fluid Layout Baffle pitch, in. Tube pitch, in. Active shell length, ft Overall shell length, ft Shell diameter, in. Shell thickness, in. Average tube length, ft Number of U-tubes Tube size, in. Effective heat transfer surface, ££2 Tubesheet thickness, in. Fuel salt holdup, ft7 Design temperature: shell side, °F tube side, °F Design pressure: shell side, psig tube side, psig Allowable working pressure:¥* shell side, psig tube side, psig Hydrostatic test pressure: shell side, psig tube side, psig Terminal temperature: fuel salt, °F coolant, °F Effective log mean temperature difference, °F Pressure drop: shell side, psi tube side, psi Nozzles: shell, in. (sched-kLoO) tube, in. (sched-i40) Fuel-salt flow rate, gpm Coolant-salt flow rate, gpm INOR-8 10 Fuel salt Coolant salt 25% cut, cross- baffled shell with U-tubes 12 0.775 triangular ~6 ~8 16 1/2 1h - 159 1/2 OD; 0.0k2 wall ~2504 1-1/2 6.1 1300 1300 25 90 s 75 125 800 . 1335 1225 inlet; 1175 outlet 1025 inlet; 1100 outlet 133 2l 29 5 5 1200 (2.67 cfs) 850 (1.85 cfs) " ", » ¥Based on actual thicknesses of materials and stresses allowed by - ASME Code. ~F b O {4 165 rods are left out at locations where neither end could be fastened. For this reason, rods are used in the horizontal direction only at the stub baffle plate and at the lower portion-of the baffle at the fuel inlet end of the exchanger. The rods at these two locations are 0.171-in. x 1/4-in. and 0.17k~in. x 1/4-in., respectively. The tubes are also restrained at the U-end of the tube bundle by rods inserted in two directions through the five outermost rows of tubes. Two 1-1/2- in.-wide INOR bands are used to hold the rods in position. One of the bands, which is slotted to accept the ends of the rods, is inserted horizontally into the tube bundle. The other band is wrapped around the outside and has the ends of the rods tack welded to it. BSee ORNL Dwgs 103%29-R-001-E and 10329-R-002-E.¥ Six 25% cut baffles of 1/L4-in. plate, spaced at 12-in. intervals, direct the fuel-salt flow across the tube bundle (see ORNL Dwg. D-EE-A-L0866). A barrier plete, similar to thé baffle plates but with no cutaway segment, is located 1—7/8 in. from the tubesheet to provide a more or less stagnant layer of fuel salt and reduce the temperature difference across the tubesheet. The baffles and the barrier plate are held in position by spacer rods, screwed and tack-welded together, to the tubesheet, and to each baffle. A divider separates the entering and leaving coolant-salt streams in the coolant header. It is fabricated of 1/2-in. plate and extends from the tubesheet to the dished head a maximum distance of about 12 in.; it is welded only to the dished head. It is positioned by guide strips on the shéll'wall, and a gfoove in the edge fits over & l/h-in. pointed, horizontal projection on the tubesheét. This arrangemeht provides a labyrinth-type seal between the channels without stiffening the tube- sheet. - | | The divider prevents use of & horizontal row of tubes at the exact centef'of the tubesheet. Also,'in'arfanging'the U-tube bundle into a configuration that could‘be assembled,'it was necéSsary to leave out the nifie tubes'én'the horizontal'fofi immediafely above and below the center. These holes are not drilled in the tubesheet. To maintain fuel- salt velocity distributions in the shell and also to keep the fuel-salt inventory to & minimum, solid rods of INOR-8, 1/2 in. in diameter, are used at these locations in the tube bundle. ¥Development drawing numbers, 166 There are 159 tubes, 1/2 in. OD by 0.042 in. wall thickness, affording a total heat transfer surface of ~254 ft2, The tubes are arranged on a 0.775-in. equilaterial triangular pitch. The tube- sheet is 1-1/2 in. thick. The holes through the tubesheet had trepanned grooves on both sides of the sheet. The grooves on the coolant-salt side were to permit the tube-to- tubesheet we1d595 to be made.between the tube and a lip of about equal wall thickness. The groove has an overall depth of 0.090 in., is 0.068 in. wide, and leaves a 1lip of 0.042 in. (see Fig. 5.28). The tubes were expanded at the tip end into the holes before welding; after welding, the tube openings were reamed to the inside diameter of the 96 tubes. ) fi The tubesheet holes had trepanned grooves on the fuel;salt side to permit back-brazing of the joints. These grooves were 0.100 in. deep, 0.100 in. wide, and with a lip of 0.025 in. (ref 94) (see Fig. 5.28). This groove held an 82% gold - 18% nickel brazing ring prior to furnace- brazing.97 The brazing operation consisted of holding the assembly between 1850 and 1885°F for 60 min in & hydrogen atmosphere having a dewpoint temperature below -80°F,9LL and a flow rate of 345 ft3/hr. Both the heating rate and the cooling rate for the brazing cycle were limited to 300°F/hr. Three 3/32-in.-diam equally spaced holes were drilled from the bottom of the braze-ring trepan to communicate with the 0.0015 to 0.003%-in. annular space between the tube and the tube- sheet hole, to permit the braze metal to flow into this space during the furnace brazing.98 An excess of the braze filler metal was provided to assure complete filling of the void and enough to form a fillet between the tube wall and the full thickness of the trepan lip. Visual examination of these fillets after brazing gave an indication that each braze void was completely filled.98 There was no apparent distortion of the tubes, and the metal was bright and clean. Ultra- | sonic inspection by use of a Lamb-wave probe, with a 3/32-in.-diam flat-bottomed hole as a standard, indicated some porosity but no open channels in the brazed joints. After fabrication the unit was hydrostatically tested to 1335 psig on the tube side and 806 psig on the shell side. The shell side was T i» 167 Unclassgified ORNL DWG 64-8820 b N 0.025 in. 0.100 in._.' I. . o % 7 Fé?é;i“fii: T (INOR-8) % : | ///////// o 0.0015 - 0.003 in. A L N\ S 0.100 in in. Clearance o 7 @ TTL‘?g//fi"éfiani ' g// 5 0 + 2 OohinR N~ /////////////// | o ‘ Io.ol+2 in. —-||—- ' —-| |-— 0.068 in. ‘__1 Figure 5.28. Tube to Tube-Sheet Joint in MSRE Primary Heat Exchanger. 1e8 pressurized first and maintained at 800 psi while the tube side was pressure 92,99 A helium mass spectrometer leak test was applied, with the tested. shell-side pressure less than 5 microns abs and the tube-side pressurized with helium to 100 psig. There were no leaks. The heat exchanger is installed horizontally, pitching toward the fuel-salt outlet at a slope of about 3°., Each U-tube is oriented so that the coolant salt will also drain. The supports are described in Section 5.5.3. The unit weighs about 2060 1b when empty and 3500 1lb when filled with both fuel and coolant salts. The fuel-salt holdup is ~6.1 £t3, and the coolant-salt holdup is about 3.7 ft°. The shell is surrounded by electric heating units of about 30 kw total capacity, as described in Section 5.5.k. In normal operation, the coolant-salt pressure will be maintained at a slightly higher value than the fuel-salt pressure so that coolant salt will flow into the fuel system if a leak develops. 5.5.2 Design Considerations The heat exchanger was designed for low holdup of salts, simplicity of construction, and moderately high performance. The space limitations within the containment cell required a fairly compact unit. A U-tube configuration best satisfied this requirement and also minimized the thermal-expansion problems in the exchanger, From the heat transfer standpoint, it was better to pass the fuel salt through the shell and the coolant salt through the tubes, since the fuel-salt volume flow rate is larger. The shell side also presents less opportunity for retention of gas pockets during filling operations. A further consideration in this respect was that the fuel-salt system operates at a slightly lower pressure than the coolant-salt system and there was a small savings in the required shell thickness. 5.5.2.1 Heat Transfer. The behavior of molten salts as heat transfer fluids had been investigated prior to design of the MBRE.IOO There was good agreement between measured values of the tube-side coefficients by Amos et al.loo and calculated values based on the generalized formula of Sieder and Tate.lOl The heat transfer design conditions are given in Table 5.9, and the physical properties of the fuel and coolant salts are given in Table 2.1. *q " 169 The mean At for a true cofintercurrent heat exchanger would be 137°F. A correction factor of 0.96 was applied to include the effects of a single-pass shell, which reduced this value to the 133°F shown in Table 5.9 (see Section VI, Ref 18). | Film coefficients were assumed to be constant on both sides of the tube wall. The velocity in the tubes is about 12.1 fps and the Reynold's modulus about 9060, giving a film coefficient of about 4900 Btu/hr-ft2-°F.* The pressure drop in the tubes was estimafed to be about 2.2 psi/ft.* (See Section VI, Ref 18) The film coefficient on the shell is estimated to be 3200 Btu/ft2-hr-°F for a Reynold's modulus of 13,000. The overall heat transfer coefficient is about 1100 Btu/hr-ft2-°F. The resistance to heat flow is about equally divided between the tube-side film, the tube wall, and the shell-side film. The overall coefficient makes an allowance of about 10% for possible "scale" deposits on the tu.bes.18 In estimating the overall capacity, or rating, of the heat ex- changer, the active length of the tubes was taken as the straight portion between the thermal barrier plate and the last baffle, since experience indicates that the heat transfer coefficient in the bends of U-tube-type exchangers is considerably less than in the straight sections. On this basis the effecfive area 1s 259 ftg, which is about 8% more than the calculated requirement for 10-Mw capacity. This extra amount, plus the "dirty tube" allowance, affords a margin of about 20% on the conserva.tive:side.18 5.5.2.2 Pressure Drops. The estimated total pressure drop on the shell side was estimated to be 22 psi at 1200 gpm.l02 Preliminary testing of the compléte exchanger indicated a pressure drop of almost twice this amount, primarily due to the inlet and outlet losses. The shell was lengthened by l-in. to.make room for an inlet impingement baffle, four tubes were removed (leaving a total of 254), and the baffle stay rods which_partially'blocked-the fuel-salt exit nozzle opening were eliminated. Subsequent testing indicated a total pressure drop at 1200 gpm of 25-30 psi.lT! ¥These values, given in Ref 18, are based on a coolant-salt circu- lation rate of 83%0 gpm rather than the rated conditions of 850 gpm. The greater velocity afforded by the latter will increase the calculated values of the film coefficients and the overall coefficient slightly. formulae 170 The estimated tube-side pressure drop was 29 psi at 850 gpm. Tests on the 25h4-tube exchanger indicated a value fif about 30 psi.lr{7 5.5.2.3 Stresses. The thickness of the shell was determined from the formulae of the ASME Unfiréd Pressure Vessel Code, Section VIII.hT The heat exchanger was designed for pressures of 55 psig on the shell side and 90 psig on the tube side at 1300°F (see Section V, p 2, Ref. 18). Except for thermal stresses in the tubes, the stresses were limited to 2750 psi. Taking into considerationlthe actual thick- nesses of material used and the higher stresses permitted by the Code, the allowable working pressures are 75 psig.for the shell side and 125 psig for the tube side at 1300°F. The tube wall thickness was based more on the weldipg requirements than on pressure-stress considerations.. Experience.héd indicated that wall thicknesses of less than 0.04 in. had more of a tendency to crack at the tube welds; therefore the tube wall thickness was more or less arbitrarily fixed at 0.042 in. This provides considerably more strength than is needed to contain the design pressure. The stresses developed in the tubes due to one leg of the U being hotter than the other are not excessive and are largely self-adjusting. The thermal stress due to the temperature difference across the tube wall 1s estimated to be a maximum of 10,000 psi and is greatest in the U-bends where the fuel salt is hottest. Under normal operating conditions the tube wall in this region will not exceed 1150°F. The stress for 0.1 CRU is about 10,000 psi at 1150°F so there should be no concern for the life of the tubes unless the reactor is operated through a large number ofiCycies between zero and full povwer at higher temperatures. . e The thickness of the tubesheet was determined by standard‘TEMA 105 to be 1.5 in. for a pressure of 55 psi across the sheét'and a pressure stress of 2750 psi. This pressure differential aésumes ‘ that the coolant salt is at 65 psig and the fuel salt is at 10 psig = (no flow condition). The thermal barrier plate on the shell side is | estimated to limit the temperature difference across fhe tubesheet-toli less than 20°F (see Section V, p 18 of Ref 18); The baffle on the coolant-salt side is kept separate from the tubesheet in order to avoid large localized stresses. by ne 171 5.5.2.4 Vibration. Development testing of the heat exchanger as constructed to the original design indicated excessive vibration of the tubes at the rated flow rate. The design was then modified to include an impingement baffle on the fuel-salt inlet and installation of "lacing" rods to restrain lateral movement of individual tubes. Subsequent testing showed that the noise due to the tube vibration had been eliminated.ll 5.5.3 Supports The heat exchanger is connected to the reactor vessel and the pump by short and stiff piping, so one of the primary considerations in de- signing the supports for the heat exchanger was that it must be allowed to move with but little restraint when the system is heated and cooled. The coolantiéalt lines attached to the heat exchanger have sufficient flexibility in looping around the reactor cell space to substantially reduce the reactions on the heat exchanger nozzles due to thermal expansioh in these lines. The heat exchanger rests on two INOR-8 saddle supports that are welded to the shell about 46 in. apart. The INOR-8 legs on which the saddles are welded are of different heights to give the shell a pitch of about 3° toward the fuel-salt outlet end. The legs are bolted to a carbon steel frame, about 30 in. wide and 10 ft 8 in. long, fabricated of 6-in. I-beams. This frame is installed horizontally and rests on four 3-in.-diam rollers (see ORNL Dwg. E-EE-D-L1492)., The support bracket for each of the rollers has a 2-15/16-in.-diam pin inserted in & thrust bearing, which carries the vertical loed and permits the ;rollers to be self-aligning. The thrust bearings are mounted on top of the Grinnel¥* spring hanger assemblies having adjustable spring tension, load indicator ahd scale. The special tension adjustment bolt can be turned by use of remotely operated tools from above (see ORNL Dwg- D-DD-thlh9l); The spring hanger assemblies rest on a fixed support structure of 8-in, I-beams. (See Section XI, Ref 18). The arrangement of supports allows the heat exchanger to move horizontally in a north-socuth direction on-the rollers, and to move vertically and rotate against the spring actions. A small amount of . 172 east-west horizontal translation (very little should be required) can be accommodated by the frame slipping laterally on the rollers to the "least-loaded" position. Piping reactions on the heat exchanger nozzles are shown on ORNL Dwg. D-EE-Z-40852 and are discussed in Section 5.6. 5.5.4 Heaters | The salts in the primary heat exchanger are képt’molten by electric resistance heaters installed outside the shell. The heater units are arranged in three sections and are essentially identical to the removable heaters applied to the 5-in. straight sections of salt piping (see Section 5.6.6.2) except that they are designed for the 16-in. OD shell. The heaters are cbnnected in three separate circuits, each three-phase, 208-v, 10-kw, to give a total heat input capacity of 30-kw. The thermal insulation is similar to that used on the pipe sections. (See Mirror Insulation Company Dwg G-108-A). ta Nyt sl 173 5.6 Primary Circulating System Piping, Supports, Heaters, Insulation, Freeze Flanges and Freeze Valves. 5.6.1 Piping With the exception of a transition piece at the pump suction, all the primary circulating system piping is fabricated of 5-in., sched L0 seamless INOR-8 pipe. Flanges are provided between the three major pieces of equipment in the loop to facilitate their removal and replace- ment. These "freeze" flanges are described subsequently in Section 5.6.k. Forged elbows are used in the piping where space did not permit use of longer radius bends. The system includes one 90° bend, one bend of about 30°, three 90° elbows, one 57° elbow and one 34° elbow. All piping in the circulating system pitches downward at 3° to cause drainage towards the reactor. (The drain line from the bottom of the reactor, line 103, pitches at about 3° to drain toward the fuel drain tanks.) The piping between the reactor discharge nozzle and the fuel-salt pump suction nozzle, line 100, is welded to the reactor nozzle and extends almost horizontally, with & slight bend, approximately 6 ft to a freeze flange, FF-100; from this flange it bends slightly in the horizontal plane and turns upwards 90°, terminating in the pump nozzle transition piece. This special conical section is approximately 32 in. long and rolled from 3/8-in. INOR-8 plate. It is required to meke the transition from the 5-in. pipe in line 100 to the 8-in. nozzle on the pump bowl. A 5-in. x 6-in. eccentrlc reducer is used at the pump dlscharge nozzle. See ORNL Dwgs E-GG-B-40700, E-GG-B- 40701 and E- GG-E-41866. Line 101 1s welded to the pump discharge nozzle and extends horlzontally about b 1/2 ft where it makes a 90° bend in the horizontal plane and 301ns the freeze flange FF 101, which is close-coupled to the heat exchanger inlet nozzle. Line 102 drops vertically from the outlet at ‘the underside of the heat exchanger a distance of about 5-1/2 ft to a 90° elbow and then runs horizontally through a sweeping 90°fbend to the freeze flange, FF-102; ffom this flange it continues horizontally through a slight bend to the reactor inlet nozzle. 17k The pump bowl overflow line is described in Section 5.4.7.1 and the drain pipe, line 103, is discussed in Section 6. 5.6.2 Piping Stresses and Flexibility Analysis The reactor vessel is suspended from the stationary top cover of the thermal shield and is thus fixed in position and the anchor point for.the piping in.the primary circulating system. The circulating loop is rather compact, with short relatively stiff lengths of 5-in. pipe con- necting the equipment. To avoid use of bellows-type expansion joints to relieve stresses due to thermal expansion, the heat exchanger and fuel ~pump supports were designed to allow relatively free movement. The fuel pump mount allows the pump to move on rollers in the hori- zontal plané and a parallel-link framework, supported on springs, permits vertical movement from the cold to the hot position (see Section 5.4.5). The pump bowl is thus restrained from rotation about any axis. The heat exchanger supports permit it to move horizontally in two directions on rollers and to move vertically and rotate about its longi- tudinal axis by acting against the spring supports, as described in Section 5.5.3. . The sustained stresses in the piping, i.e., those due to internal pressure and weight of the equipment and contents, were estimated using conventional relationshipsh7 and found to be less than the allowable stress of 3,500 psi at 1300°F. 10 Flexibility analyses were made on the primary circulating system piping using the IBM Modification of Pipe Stress Program, SHARE, No. GS 5812.9l Estimates were based on a reactor power level of 10 Mw when the primary piping is between 1175°F and 12250F, the coolant-salt piping is between 1025°F and 1100°F, and the reactor vessel and heat ex- changer are at about 1200°F. TFor every anticipated reactor bperating condition the maximum stresses were calculated to be well below the al- * loweble stress range of 32,125 psi, as determined from the Code of Pressure *See p 96, ref 106. Based on 8, = £(1.25 S8+ 0.25-8,_), where S allowable stress range, psi; f is stress reduction factor, taken to bé unity for less than 7,000 full temperature cycles over expected life; S is allowable stress in cold condition, taken as 25,000 psi (see ref 16)$ and is allowable stress in hot condition, taken as 3,500 psi at 1300°F (see Tef 16). L ¥ | e 175 C s 106 . C Piping, ASA B3l.1l. The maximum stress in the piping system was estimated to be 7,700 psi, which occurs at the coolant-salt inlet nozzle 9l Calculated movements of the pump from the cold to the hot condition at 10 mw were: Ax (N-S8) = 0.401 in.; Ay (E-W) = 0.335 in.; and Az (vert) . 91 | = 0.826 in. to the heat exchanger. 5.6.3 Supports There are ten supports on major piping inside the reactor cell, three on the fuel-salt piping and the remainder on the coolant-salt lines. Rigid supports can be used at one location in the fuel-salt system and at two places in the coolant-salt piping; at all other locations the piping rests on spring-loaded mountings. The supports for drain line 103 are described with the drain tank cell salt transfer line supports, Section 6.28. The spring.supports are Bergen Pipe Support Corporation (New York, N.Y.) units, Mod&l VS-3F, in sizes 3, 5, 6, 7 and 8. The spring setting in each is variable to adjust the support to the piping load, as will be discussed subsequently. A short column of 3-in. sched 4O pipe rests on the spring support and carries a 10-in. x 10-in. x 1/2-in.-thick steel plate at the top.” Nine 1-in.-diam steel balls (Mathews Type 101) are mounted on top. of the plate, A similar horizontal plate, which rests on top of the balls, is welded to a bracket arrangement extending through the thermal insulation at the bottom of the pipe. These plates, with the ex- ception of the plate at support S- 2 are installed parallel with the slope ~ of the pipe at each location. The supporting arrangement. thus allows freedom of movement of the piping in the horizontal plane, provides a variable spring force 1n the vertical direction, and by supporting from below, allows the piping to be removed for maintenance Operations Without disturbing the support structure. (See ORNL DWgs E-GG-E- h1886) | The support loads and the movements of the piping were estimated u51ng the methods given the Bergen Pipe Support Corporation Catalog No. 59. o7 These values, for both the fuel-salt and the coolant- salt piping inside the reactor cell are summarized in Table 5.10. The follow1ng 107 weights were assumed in making the estimates: 176 5-in. sched 40 INOR-8 pipe 15 1b/ft Weight of salt in pipe¥* 21 " Thermal insulation 3 " Electric heaters 5 " Support frame 0 " Freeze flange and clamp 290 " Clamp frame 212 " The movements listed in Table 5.10 are for uniform heatup of the system to 1300°F. The values for actual operation may differ slightly. In most instances the springs will exert upward forces on the plping when the system is cold. These forces approximately equal the weight of the salt in the effected portion of the system. | , | A description of the forces on a typical support, 5-3 on line 201 in the coolant-salt piping, will explain the operation. The spring in this support is initially compressed 1-11/16 in. and a‘plug is inserted to maintain the spring in this position. The spring scale pointer will read 608 1bs. The support is then placed in position and the empty pipe load of 397 1lbs 1s rested on it. Since the pipe will expand l/h in. upwards when heated, a second spacer 1-7/16 in. long is substituted for the first one. The spring will then exert the full 608 1lbs force against the pipe, with a resultant upwards force on the pipe of 211 pounds. As the system is heated, but still empty of salt, the pipe expands upwards and the spring also expands the 1/4 in. maximum travel allowed by the 1-7/16-in. travel stop spacer piece. The spring scale will then read 581 1lbs, but no force greater than the 397 lbs weight of the plpe can be exerted because of the travel stop. When the system is filled with salt, an additional 18%4 1bs must be carried by the support; the total piping load of 581 1lbs is thus counter balanced by the spring setting of 561 1bs.107 The variable spring support, S-10, for line 101 is compressed when the system is cold in order for it to give full support after the pipe has moved 3/8 in. upwards to the hot position. The cold spring setting is 188 1bs and it supports & weight of 180 1lbs at operating conditions. *In estimating the weight of the salt in a pipe, a density of 150 lbs/ft5 Qfi) was used in both fuel and coolant-salt systems, since the difference in ' the weights amounted to but 4 1lbs/ft of pipe. | " b n - ¢ o Table 5.10 Variable Spring Supports for Fuel and Coolant-Salt Piping Inside Reactor Cell upport Line Support Load Support Load Pipe Hanger Type Spring No. No. (Pipe Empty) (Pipe Full) Movement and Size No. Setting Remarks 5-1 100 - - 1/8" Down | Rigid Support | No Spring %gfofifbiggggrzftgigz /e §-2 102 234 1bs 316 1bs 3/8" Down | PSTESD gS5F o3k 1ps | Ineert stop fo ;?gignfown- 5-3 201 397 1bs 581 1bs 1/ up | PEIECR IS | gog aps | BSCTY :ZOE/EOii%mit upvard S-1 201 42 1bs 503 1bs 1/8" up | POrESD gSEF 514 1bs | [0SCTY izof/goiifmit upward 5-5 201 347 1bs 468 1bs €0.06" Up | Rigid Support | No Spring nghogozggioig ;gp:e flush 5-6 200 277 1bs 372 1bs 3/8" Up Be;f:g ZSBF 394 1bs i?:ig; igog/goiifmit upward 5-7 200 42k 1bs 683 1bs /ht up | BEIESR ST ) mi5 apg | RSeTY §§°f/fi°iifmit upvard o [ an | wome | te e w | BT | | e o e 5-9 200 301 1bs 389 1bs <0.05" UP | Rigid Support | No spring 3§§h°gozzggog§ zgpze flush $-10 101 10% 1bs 140 1bs 3/8" Up Be;fj: §S5F 148 1bs ifiizrzrzzgf o ;}gizn?P' LLT 178 The piping between the heat exchanger and the reactor, line 102, also has a variable spring support, S5-2. As the system is heated the net thermal expansion of line 102 is downward about 3/8 in. The support is installed with a spring setting of 23 lbs, which is 82 1bs less than the calculated hot position loading of 316 lbs. During system heatup, the 3/8-in. downward expansion of the pipe exerts a force of 17 lbs and com- presses the spring to the stop. The unit then acts as a rigid support and when fuel salt is added to the system there is no further spring deflection. Supports S-1 on line 100, S~5 on line 201, and S-9 on line 200, each carry the weight of a freeze flange. Since the movement of the pipe at these particular support points is negligible, rigid-type supports are used. The piping supports in the coolant cell are described in Section 8.6.2 and those in the fuel drain tank cell in Section 6.5. 5.6.4 Freeze Flanges Mechanical-type joints are provided in the 5-in. piping in the fuel and coolant-salt systems inside the reactor cell to permit the ma jor equipment to be disconnected and removed for maintenance or re- placement. The locations of the five flanged Jjoints are shown in the flowsheet, Figure 5.3. The so-called "freeze flange" type of Jjoint was adopted be- cause of its proven reliability in providing tight connections with zero salt leakage and insignificant gas leakage under all anticipated thermal cycling conditions. It is also a Jjoint in which the salt does not contact the ring-joint gasket, an important factor in that residual salt would be difficult to remove with remotely-operated tooling. Salt particles in the ring joint could cause corrosion of the seating surfaces when the salt is exposed to moisture and air and thus make the joint difficult to reseal to the necessary leak tightness. There is also an advantage to keeping the salt out of the ring joint in that there is less scatter of salt particles as the flanges are separated. Figure 5.29 shows a sectional view of a typical flange and clamp assembly (also see ORNL Dwg. E-GG-C-40610). The 23-in.-diam flanges are held together by two semi-circular spring steel clamps which are forced around the circumference of the flanges. The spring action rh ' 179 UNCLASSIFIED ORNL-LR-DWG 63248R2 FLANGE CLAMP GAP WIDTH BUFFER CONNECTION {(SHOWN ROTATED) MODIFIED R-68 RING GASKET FROZEN #%g-in. R SALT SEAL 0.050-in. GAP WIDTH | -R{TYP) SLOPE {:4 (TYP) 5-in, SCHED-40 PIPE — ittt . — - - - - Fig. 5.29. PFreeze Flange and Clamp. 180 exceeds the piping code106 requirements for gasket loading in pro- viding more than 136,000 1b of clamping force and also affords a more constant gasket loading during thermal cycling than would be obtainable with more rigid fastenings; such as bolting. The arrangement also was amenable to design of equipment and tooling for remote assembly and disassembly of the joint from above. Hydraulically operated jacking tools are lowered into the cell to provide the five to ten tons of force required to install the clamps. Once installed, no external force is required to keep the clamps in place. The same Jacking tools are used for separating the clamps and the forces required are only slightly less than those needed for installation. A clamping frame is provided for each of the five flange installations inside the cell but the jacking tools, etc., are interchangeable and may be used at each location.¥* 5.6.4.1 Flanges. The flanges are fabricated of INOR-8 and are about 23-1/8 in. OD and 1.484 in. thick when measured through the thickest portion of a flange face. They are the welding-neck type. The male flange has a guide ring, 5.798-5.802 in. diam by 1.248-1.252 in. long, welded into the face on the same centerline. The outside of the guide ring is tapered at 15° so that as the flange faces are brought together during assembly operations the ring will enter a similarly shaped opening in the female flange to guide the two together in correct alignment (see ORNL Dwg D-GG-C-40611 and 40612). In each case the male flange is installed facing "uphill" in the salt piping, all of which slopes at 3° to promote drainage. A groove, 0.344 in. wide x 0.25 in. deep x 20.375 in. pitch diam, is machined to close tolerances in the face of both the male and female flanges to accommodate the ring gasket. The flange faces are also machined in the vicinity of the grooves to serve as gaging surfaces. Either the male or the female flange is drilled with a 3/32-in.-diam hole through the bottom of the groove for the helium buffer gas and leak-detection connection. The flange half selected *¥Due to crowded conditions, the flange in line 100 may require a special offset jacking tool. L "% 181 is the one judged to be less likely to require removal. The hole is trepanned on the back side of the flange for the welding of a 1/8-in. sched-40 pipe. The connection is made at a point on the flange which falls between the two semi-circular spring clamps (see ORNL D-GG-C-L0615). The sliding surfaces for the clamps on the backs of the flanges have first a 6° and then a 3° slope to draw the flanges tightly together, and then a remp with 0° slope to make the clamps self-retaining. These surfaces have a machined finish (32 RMS micro-in.) and are care- fully contoured to provide the required gasket loading with a minimum of surface galling or stress concentrations. A graphite-alcohol lubri- cant, "Nearlube," is applied to the flanges before applying the clamps. As indicated in Fig. 5.3%2, a clearance of 0.030 in. is provided between the flange faces at the outer circumference to take care of tolerances in machining of the ring gasket and groove and also to allow for deformation of the flange under internal pressure loading, a condition which tends to close the clearance gap at the outer edge. A groove, or line, is cut around the circumference of each flange disc to serve as a reference mark for the optical alignment of piping inside the reactor cell. The outside edge of both the male and female flanges has two projecting lugs, or ears, horizontally 180° apart, which are used in the disassembly operation to be described subsequently. As shown in ORNI, Dwgs D-GG-C-LO611 and L0612, these ears are about 1.625 in. wide and project about 1-1/4 in. 7 | ‘ Flange loadings, stresses,‘afid,deformations are discussed separately under Sections 5.6.4.6 and 5.6.4.7, following. 5.6.4.2 Ring Gasket. The ring gasket.is fabricated of . nickel (ASTM B-160). This material was selected because it is sufficiently softer than INOR-S to seat properly and has & similar coefficient of thermal expansion* to remain tight after thermal ecyeling. The ring has a pltch diameter of 20.375 in. (% 0.002 in.) and has the inner and outer edges rounded to a radius of 0.155-0.157 ¥The coefficient of thermal expansion for Ni at L00°F is 5.66 x 1076 in./in.-°F; for INOR-8 the value is 6.45 x 10-6 in./in.-°F in the T0-400°F range. 182 in. The ring is machined to the close seating lolerances required through use of a special jig furnished to the manufacturer, as shown on ORNL Dwg D-GG-C-4061k. In common with other leak-detected ring Jjoings in the MSRE, the gasket seats on both sides of the groove to form two sealed spaces which are buffered with helium and monitored for leakage. A 1/16-in.- diam hole is drilled through the ring in two places to allow the sealed and buffered spaces to communicate. | The inside surface of the ring is drilled with eight equally- spaced 1/16-in.-diam holes, about 5/32 in. deep, to accept the re- taining pins on the salt screen, to be described subsequently. The inside surface of the ring also has a "notch" 0.062 in. deep and to & radius of 1 in. at the bottom and two side-by-side identical notches at the top to engage the remotely operated tool used to maneuver the ring during maintenance (see ORNL Dwgs D-GG-C-40611 and L4061kL). A small 304 stainless steel bracket is fastened with flush-headed screws to the outside of the seal ring at the top. This bracket supports a l-in.-long horizontal pin formed from a 304k stainless steel 1/4 in. x 20 UNC bolt which has the top portion of the threads ground away. This pin is inserted in a l/h~in. tapped hole at the top of the male flange when the ring is to be positioned for reassembly of the joint. The lack of threads on top of the pin allows it to be slipped into the hole, but when released, the threaded portion prevents it from slipping out, thus retaining the ring in position for mating of the two flange faces. All the male flanges are made with a similar tapped hole on the bottom to allow them to be installed either side up and thus provide more interchangeability of parts (see ORNL D-GG- C-406LT). 5.6.4.3 8alt Screen. The 0.050-in.-wide clearance between the male and female flange faces contains a. salt-retaining screen formed of 0.015-in. OD INOR-8 wire on a 20-by-20 to the inch mesh., Salt entering the cavity solidifies on the screen, the uninsulated flanges being cooled by loss of heat to the cell atmosphere. No other source of cooling is required. e by 1 1] U 183 At & salt temperature of 1200°F, the freeze point is about 5-5/8 in radially from the center of the pipe. This distance decreases about 11/16 in. for every 100°F decrease in bore temperature.lo8 The screen helps somewhat in preventing the salt from moving radially outwards, but, more importantly, when the Joint is disassembled, provides a con- venient means of removing the frozen salt as an intact cake. Undue scattering of salt particles is thus avoided. The flange faces have very little salt adhering to them. The outer edge of the screen has eight equally spaced radial pins, 1/16 in. diam by 3/4 in. long, which engage the aforementioned holes in the seal ring to join the two units together for convenience in handling. The outside edge of the screen has a 3-in.-wide by 3/k-in. notch at the top and a 1-1/U-in.-wide by 3/4-in. notch at the bottom to allow access for the ring gasket holding tool mentioned above. (See ORNL Dwg D-GG-C-LO617) 5.6.4.4 Clamps. The clamping rings are fabricated of No. 4130 heat-treated steel forgings made to ORNL Specification 81-180, and as shown on ORNL Dwg D-GG-C-40616. After welding, the clamp assemblies are quenched from 1550°F and tempered at 800°F to obtain a surface hardness of 380 BHN. This material was proven to have a sufficiently high yield strength to provide the necessary clamping load, and with the hardened surfaces, to be sufficiently compatible with the INOR-8 to minimize galling. The clamping rings are more or less U-shaped in cross section, with the base portion about 1 in. thick and the legs tapering to 5/8 in. in thickness at the ends. The clearance between the legs is 2.908 in. (#0.010 in.). The semi-circular pleces have the inside corners rounded to arj/h-in. radius and are contoured to prevent digging in and galling of the INOR-8 flanges at these points (see ORNL Dwg D-GG-C-40616) . | | Right and left hand guide ears are welded to both the upper and lower clamp halves. These ears are also fabricated of No. 41%0 steel and are heat treated along with the clamps. Each ear is formed of two more or less identical pieces with a 1/8-in. gap in between. This arrangement was proven necessary to prevent stiffening of the 184 backbone of the clamp at the ear location, with subsequent overstressing or galling of the sliding surfaces at these points. The ears have a 1-5/8-in. by 2-1/32-in. opening through which the clamping-frame guide bars pass, as will be explained in Section 5.6.4.5, to follow. | The top and bottom halves of the clamp are each drilled with a l-5/8-in.—diam hole to permit passage of the 1-1/2-in.-diam load transmitting rod on the clamping frame, as described below, 5.6.4.5 Clamping Frame. The clamping frame assembly is shown schematically in Fig. 5.30 and on ORNL Dwg E-GG-C-40610. The frame allows the clamps to be moved as a unit into position around the mating flanges and then serves as a leverage point for applying hydraulic jacks on each side of the clamps to draw them together. Since the frame encircles the pipe, it must remain inside the reactor cell after assembly of a Jjoint. For storage it is moved along the pipe to a supporting rack. The clamping frame is about 33-5/8 in. wide by 55-1/2 in. high and is 7 in. thick. It is fabricated, in most part, of ASTM A285 Grade C steel. The upper and lower pieces of the assembly are Jjoined by 1-1/2 x 2 x 34-in.-long guide bars on each side. The upper and lower ends of these two bars have 1-3/8-in.-long oblong holes through which a §/h—in.—diam pin is mounted to provide a freedom of movement of the upper and lower elements to make the clamps self-aligning. The inside of the rods at mid-height have two projecting lugs to engage the lugs on the outer rims of the flanges, as mentioned above. A 1-1/2-in.-diam rod extends downward about.10 in. from the center of the upper element, or beam, of the frame and a similar rod extends upward from the lower beam, both rods passing through the holes in the respective semi-circular clamps. The purpose of these rods is to transmit the load, or force, when removing the clamps. Brass pads are brazed on the ends of the rods to avoid injury to the flanges. The distance between the ends of the rods is about 1/4 in. greater than the overall diameter of the flange discs. To install the frame it is first moved from the storage rack using the liftingeyes on the upper clamp. In this position, the upper beam will drop down until its ears bear against the clamp ears. 4. & Guide 11 Representation of Clamp Operator Tool o, Clamp Beam ) Y 71 * T\ L/ Putting Both Clemps On ng Lower Clamp Unclassified ORNL DWG 64-8821 ¢8T — 1 - ng Upper Clamp Figure 5.30. Freeze Flange Clamping Frame Showing Assembly and Disassembly. 186 The lower clamp also drops down with its ears bearing against the lower guide-rod-pin joint housing. The frame is then moved horizontally along the pipe and lifted into position with the lugs on the flange rims between the two lugs on the frame guide bars. The clearance between the lugs is about 5/52 in. so that close alignment is not required. The upper clamp is then lowered, as indicated in Fig. 5.30, so that the bottom end of the upper load-transmitting rod rests on the top of the flange, the clearance in the pinned joints on the guide bars allowing the necessary movement. The hydraulically operated Jacking tools are then applied to each side, the jaws of this tool closing around the top of the upper clamp ear and the bottom of the lower clamp ear., The Jjacks are operated simultaneously, drawing the clamps into position. The pressure to the jacks can be varied as required to draw the clamps on evenly. The force required on each side is 12,000 to 24,000 1b, depending on the condition of the sliding surfaces, the sum of the dimensional tolerances, etc. In disassembly of a Jjoint, the lower clamp is removed first. The jaws of the jacking tool are placed above the ears on the lower clamp and below the lower pin Jjoint housing, as shown in Fig. 5.30. The lower load-transmitting rod will push against the bottom of the flanges and transmit the Jjacking force, with no load being carried by the pin joints on the guide bars. Unequal distribution of the friction between the clamp and the flanges may cause one side of the clamp to tend to "get ahead" of the other, an action which is self- multiplying. The resulting forces tending to move the frame out of vertical, i.e., rotate about the flange, are counteracted by the lugs on the flange rims bearing against the lugs on the guide bars. Since the first rotational movement takes the "slack” out 6f the pinned gulide bar joints, the position of the pin in the slotted holes serves as an indication to the operator that the jacking force on one side of the clamp should be reduced. If sufficient imbalance occurs to move the guide bars to the limit of their travel in the pinned joint, the end of the bar butts against the housing to transmit the load rather than acting through the pin. L LE 4 M 187 The upper clamp is then removed, using the jacking tool as shown in Fig. 5.30. The upper load-transmitting rod is effective in this case and, again, the guide rods and pins carry little of the load. The force required to remove a clamp is only slightly less than that needed to install it. After both clamps have been loosened, the upper clamp and frame assembly can be raised and moved horizontally out of the way. Once the flanges have been separated by more than 2 to 3 in., the frame could be removed from the reactor cell, should this be desirable. | A detalled description of operation of the clamping frame and associated tooling is giveh in Maintenance Procedures, Part X. 5.6.4.6 Gas Leak Rates During Thermal Cycling. Changes in gasket loading, and thus the gas leak rate, occur during temperature cycling. This is due to the differences in the coefficients of thermal expansion of the flange material (INOR-8), the ring gasket (nickel), and the flange clamps (No. 4130 carbon steel). The resiliency of the clamps, however, causes the load on the gasket %o be more constant than if more rigid fastenings were used. | Even if excess temperatures existed at a freeze flange, allow- ing the salt to come in contact with the ring joint gasket, no salt leakage would occur. (Some damage might be done to the ring sesl, however.) Thus, the only manner in which salt could leak would be for gross failure and separation of the flange faces. Tests of early models of the freeze flanges demonstrated, however, that gas - leakage could be encountered.lo9 VFor'this reason, the development tests were primarily concerned with measurements of helium gas leak- age from the leak-detected buffer zones. | Tests of the effect of thermal cycling on gas tightness showed that the MSRE flange design maintained acceptable gas seals under high temperature:(about 1300°F), under repetitive cycling (in which the'fémperature was raised from 150°F to 1300°F and returned to 150°F in a 24-hr cycle, for more than 100 cycles), and under severe tempera- ture transients (100°F/min for six minutes). (See p 10 ref 110) The joints displayed the desirable characteristic of having a smaller 188 gas leak rate at the higher temperatures than at lower. After %6 ‘thermal cycles, typical leak rates were 2.6 x lO“6 ce/sec in the cold condition and 0.39 x 10'6 cc/sec in the 1300°F condition (see p U5 ref 108). The effect on the leak rate of the interchangeability of parts was investigated (see p 41 ref 108). Two female flanges were thermal cycled several times and then mated with new (uncycled) male flanges and gasket rings to simulate the situation which might exist in the replacement of a major component in the reactor cell. Both pairs sealed satisfactorily, even after subsequent extensive thermal cycling. ‘ A gasket ring with an octagonal cross section was found to seal better than one with an oval cross section, but both performed more than adequately (see p 43 ref 108). 5.6.4.7 Loading and Stresses. The clamping force which can be exerted by the clamps was estimated to be between 136,500 1lb and 241,200 1b, depending upon the combinations of tolerances that could exist in the fit of the various parts.lll The gasket loading re- quired for proper seating was calculated using the method outlined in Par UA-4T of Section VIII of the ASME Unfired Pressure Vessel CodehT, and estimated to be about 28,800 1p MY thus capable of seating the ring gaskets with ample reserve for The clamps are withstanding pipe stresses and internal pressure. The force required to drive the clamps onto the flanges is a maximum just as the legs of the clamp slide onto the ramp with 0° slope. This force was estimated to be 24,750 1lb for each side of the clamp (if the clamping force is 241,200 1b), or a total of 49,500 1b for each of the clamp halves.lll This estimate assumes a coeffici- ent of friction between the clamp and the flange of 0.15, a value which is ample in most cases but could be exceeded if gallinglshould occur. Under maximum clamping effort, the maximum stress in the clamp was estimated to be about 90,500 psi, and the maximum clamp deflection 0.092 in. The clamp is forged and heat treated to have a yield 111 - strength of greater than 100,000 psi. A i q 189 The mechanical stresses in the flange due to axial loadings resulting from thermal expansion in the piping systems were found to be less than %000 psi. 1z This value includes the effect of internal pressure. The total axial loading resulting from a stress of LOOO psi is 17,200 1b (based on 6-in. OD by 0.204-in. wall thickness tubing)}. The allowable axial loading on the flange wailgstimatedlll using methods developed in the Sturm-Krouse study, and based on an sllowable working stress range of 30,000 psi,* a value of 86,936 1b obtained. The flange is thus capable of withstanding the axial loadings with a factor of safety or more than four. The flange internal thermal stresses were analyzed both analytically and by photoelastic studies to determine the stress concentration factors.l]_'5 (These estimates were based on 6-in. 0D tubing, but are applicable.) These studies indicated that the stresses could be higher than the elastic limit and that plastic strain could exist. Development tests proved that both radial and transverse strains occur, the former causing & reduction in the bore dismeter, and the latter a distortion of the plane surface of the face., One test showed that after 36 thermal cycles the female flange bore decreased by 10 | mils and the male bore by 30 mils. No permanent distortion was noted on the outer surfaces of the flanges (after 30 cycles) but the "out-of -flatness" of the interior face of the female flange increased from 14 mils to a value of 18 mils. No warpage was detected in the msle face. These strains are Jjudged te be of such magnitude that a large number of strain cycles could be applied_witheut failure.n3 Further, the differences between the deformations of the faces at 1300°F and at 850°F (the salt liquidus temperature) are not sufficiently great that "excess" salt could be trapped between the flange flaces to cause ebnormally high stresses or distortions. Thus, the plastic strain rthat occurs is small and flanges of the design used in the MSRE have ,undergone more than 100 thermal cycles (probably equivalent t0 10 to 15 years of normal MSRE operation) with no significant leakage, or defor- - mations of'c:onsequem:e.:Lll ¥As indicated in the footnote, Section 5.6.2, a more recent value for the stress range is 32,125 psi. 190 5.6.5 .Freeze Valves 5.6.5.1 General Description. The flow of salt in the MSRE drain, fill and processing systems is controlled by freezing or thaw- ing a short plug of salt in a flattened section of l—l/2-in. pipe, called a "freeze valve." This arrangement was adopted for the MSRE because of a lack of a mechanical-type valve with a proven reliability in molten-salt service.* The freeze valve concept, on the other hand, has a good record of satisfaétory application.' While mechanical-type valves would have the advantage of faster action and ability to modu- late the flow, the freezing and thawing times for the freeze valves are satisfactorily short and the "on-off" type of flow control does not impose any particular handicap. There are a twelve freeze valves in the MSRE. All are fabri- cated of l-l/2—in. pipe. Six are installed in l»l/E-in. lines and six in 1/2-in. lines. As may be noted in Table 5.11, one freeze valve is located in the reactor drain and fill pipe, line 103, and is inside the reactor furnace. Six of the freeze valves are in the fuel drain tank cell, three are in the fuel processing cell, and two are in the coolant cell. Figure 5.32 shows the general arrangement at a freeze valve. The valve illustrated is used at FV-10k, 105 and 106, but with the exception of the flat-plate heaters, is also typical of wvalves 107 through 112. Electric heat is applied, either directly or indirectly, to thaw a valve and to keep it in the open condition. A stream of cooling gas¥** or air is used to cool the pipe section to freeze a salt plug and positively stop the salt flow. Some system gases may diffuse through the frozen plug but the seepage through the valve is inconsequential to operation of the MSRE. A 4} ¥Preliminary investigations at ORNL of Kenametal seats and poppets, electrically-driven actuators, etc., indicated that a mechanical- type valve for molten-salt service may be practical provided that a satisfactory stem seal could be devised with reasonable effort. *¥*Cell atmosphere gas, consisting of about 95% N, and 5% 05. = ¥ ) w/ » 191 Table 5.11 MSRE Freeze Valves Freeze | " Cell in Line S Coclant Gas Freeze | Thawing Time, min Time Temperatur Valve - Line Function which FV Size Type of Heater and Insulatiod Supply | Ges Flow, scfm | Time, ill Re- ing s ¥ Line No.| ' is in. IPS ¥ cas | Tine Tigh H’l el Min With | Without | o° o | Thawing: | n . . b olding * Power Htr. On |Freezing Located : ‘ No. Rate Rate Fover gen, min. Gas On - . ‘ ' Calrod around hor. flat sectiofl; a b Down to 103 | Reactor drain and fill Reactor 1-1/2 | Zog Plow shroud with insulation. | 2 | 0 70 15° | <30 5 < 10 - 1100 | U450, ,. ' . Fuel Drain Insulated gas flow box with | c " Down to 104 Flush tank drai? and ?i;l , Tank 1"1/2 removable flat-plate ceramle }_ Nfi 908 35-70 15 - <10 <20 > 30 750b , —| heaters on adjacent piping. Re- 1 Drain Tenk No. 2 drain and fuel el | 1-1/2 | movable exterior imsulation, t;’ N, | 909 " " - - - - " " 2 . IR vhich heaters are attached, 106 Drain Tank No. 1 drain and' - Fuel Drain covers both heaters and freeze i N‘ 910 " " - - - - " " | £i11 - e Tank valve section. oA 2 | 107 Transfer to fuel processing Fueéagiain 1/2 & Nz o1 " " - _ _ - " " ) . ) ) s Fl.lel Drain . . - : :,r . . 1 " - - - - " n 108 ‘Transfer to fuel processing Tank 1/2 Insulated gas flow box with per- ‘Né 912 ———— . » 3 manently-instalied curved plate . ‘ Fuel Drain Co : " 109 Transfer to fuel processing Tank 1/2 ceramic heaters on adjacent ; N2 913 n - - - - L n ' . o : T piping. Exterior insulation . | Fuel covers piping heaters and freezer " l;o' Transfer to fuel s#oFage Processing 1/2 section. Spare heaters are ind . Adr %69 " - - - - " " : : . _ stalled. ! 111. C : . . F‘u.el 7 : ' " It - - - - 1"t " : Transfer to portable cans Processing 1/2 Air | 929 112 | Transfer to salt disposal Fuel 1/2 Mr | o2k " " - - - - " " Processing ' - ” Coolant Calrod around hor. flat section; | | 20k Coolant system drain Drein '1-1/2 | no shroud and no insulation on’ Mr| 906 25 15 <15 <5 <25 > 30 : freezer section. Adjacent pipe Co Coolant - has pema.nently-insta.lled curved _ " " " " " " " n 206 Coolant sysfiem drain - Drain 1-1/2 plate ceramic heaters and insul. Ax 07 ; > Gredtef than. d Deep frozen, no gas flow req'd ' £ Abour 20 in. from center < Less ‘than. "« Not appliceble, or not important. a Cell atmosphere gas (95% N, - 5% 02) b High rate, or freezing gas flow. ¢ Low raté, or holding gas flow. e Thermocouples listed are only those with "FV" prefix. | i it e e of valve on leg without pot. At tee between freeze ~velves 105 and 106. es, F Thermocouple Numbers® . Freeze reezing: At At 5 in. Neaxb At Valve Iégld:cl)ng Gas Off | Center |Shoulders [From Ends ¥ Pots Line No. s On k50 up | Less than _ 28, 2B | 1A, 1B to 650, 450 34, 3B none none none 103 c | 750 up~ | Less thay 1A, 1B T _ " " 24, 2B éfi; %g Ak, B4 | 64, 685 54, 5B | 105 " " 2A, 2B %‘fi’ Jgg Ak, B+ | nome | 54, SB | 106 ) " n 1A, 1B bA, 5B 24, 2B 34, 3B A, B4 none éa 68 | 107 o " lA, 1B SA, 5B " " lA; 1B 5A, 5B 24, 2B 34, 3B A, B4 none. | £ A 6B 109 " u 14, 1B 94, 5B 24, 2B 34 3B Ak, Bh none 65, 6B 110 " " 24, 2B %‘i’ ég A4, Bd | nome | 5A, 5B | 111 3 " " 24, 2B Jéi’ %g A, B4 | none | 5a 5B | 112 s " " 2A, 2B éfi: ;g Ak, Bh none | 54, 5B 20k 7 " " 24, 2B ;‘fi’ %‘g Ak, B4 none none 206 3 192 The valve "body" in each case consists simply of a flattened section of the piping about 2 in. long. The shaping was done at room temperature using a forming die in a hydraulic press. Each section was dye-checked after forming, although there was no evidence of a tendency for cracking. Sections identical to those used in the MSRE were tested through more than 200 freezetthaw cycles without evidence of over-stressing or cracking. All the freeze sections, with the exception of the one in line 103, are installed with-the flat faces in a horizontal plane. A cooling gas flow of 15 to 55 scfm will freeze a valve, initially at 1200°F, in 15 to 30 minutes. The gas flow is then reduced to 3 to 7 scefm to maintain the valve in the frozen con- dition (i.e., with the salt below 850°F) but limiting the growth of the frozen plug to the freeze valve sectlon. To allow longer plugs could cause unacceptably long thawing times and/or present . the opportunity to thaw the center section of the plug while the ends remain solid, thus perhaps overstre831ng the plpe wall. _ | In most cases a shroud, or box, is used to direct the flow of cooling gas around the freeze valve ‘section and to prevent the gas from cooling nearby heated surfaces. The fihermal insulation arrangement at the freeze valve helps establish the freezing and thawing times. The time allowed depends upon the particular ap- plication. For example, the freeze valve ih line 103 is designed to melt the plug in about 5 mlnutes, while others may take sub- 'stantlally longer . Short vertical lengxhs of L-in. NPS piping are placed at most freeze valves to form syphon breaks, or "pots," which insure that ample salt will remain in the freeze valve section after a salt trans- fer to provide a full and solid frozen plug. Where freeze valves are installed in 1/2-in. lines, the pipe size changes to 1-1/2 in. at the reservoir. 7 | | ) Design-and development of the freeze valves did not lend it- self to analytical treatment of the stresses, heat tranefer, ete., because of the irregular shape of the section and the unpredictable temperature distributions. The MSRE freeze valves, therefore, are — TN 0o o in @ 193 the result of development testing, primarily with regard to the arrange- ment of the heaters and coolers to attain the required freezing and thawing times, and to provide stations that could be maintained with remotely-operated tooling. 114 5.6.5.2 Definitions of "Deep Frozen, Frozen and Thawed". These terms were defined to have the following m.ee.nings:115 a. Deep Frozen. The salt plug is frozen, and will remain so, even on logs of electric power, cooling gas supply, etc. The heaters on the freeze valve are off, and mey be off on piping adjacent to the valve. The cooling gas may or may not be supplied to the valve. b. Frozen. Heaters on the valve are off but the heaters on adjacent piping are on, the plug remaining frozen by the cooling action of the gas stream. These valves will thaw in a specified time if the electric power fails (causing loss of the gas flow and power to the heaters) and will remain thawed for at least 20 minutes. c. Thawed. Electric heaters on adjecent piping and/or on the valve are on; the cooling gas flow is off. If electric power fails, the valve remains thawed for at least 30 minutes. 5.6.5.3 Thermocouples. In general, two thermocouples are attached on the upper surface at the center of each freeze valve section; two are attached to the upper surface of each "shoulder" (the transition between the round pipe and the flattened section), and one couple is attached to the bottom of the pipe at each end about_sfin.afrom'the centerline of_fihe freeze valve. Thermocouple locations are shown on ORNL Dvg D-HH-B-LO543, and the thermocouple numbers are 1isted in.Table 5.11. It is to be noted in this table that only those couples with an "FV" prefix are listed and that near- by thermocouples having‘llne;numberrdesignations_are‘notfilncluded. ~The chromel—alumel, mineral-insulated thermocouples have Inconel sheaths 1/8 in. dlam, and ere attached by welding the sheath to the ground surface of a weld-deposited INOR-8 pad, about 3/8 in. square by 1/16 in. thick, on the process piping. All the installed thermocouples are used in the circultry. About half, those with an "A" suffix, lead to control modules, and the others, with & "B" suffix, are used irn the monitoring circuits. If a spare 194 should be needed, a monitoring couple can be diverted for that purpose. Some thermocouples provide the signal for two amplifiers, one for the low temperature setpoint and the other for the high setpoint. If the temper- ature at the center section of a freeze wvalve rises above l}OOOF, or falls below a set value, an alarm will be sounded.116 The absolute value of the control setpoint temperature depends upon the freeze valve function, the type of heaters and insulation, etc., so that study of each thermocouple installation is needed in the field to make final settings. The nominal setpoint temperatures are given in the thermocouple tabulation, ORNL Dwg D-AA-B-L0511. 5.6.5.4 Freeze Valve 103. This freeze valve is in the reactor drain and fill line and is located within the reactor furnace adjacent to the reactor vessel. Tt is frozen, and maintained frozen, by a cooling jet of gas directed against it. It thaws quickly when the gas flow is interrupted due to the residual heat within the pipe wall. The 1 1/2-in. sched 40 INOR-8 drain line is flattened for a distance of about 2 in. to a flow area 1/2 in. wide, giving it outside cross sectional dimensions of 0.79 x 2 1/2 in., overall. The shoulders of the flattened section make an angle of about 300 with the pipe axis. The valve is installed with the flattened faces in the horizontal plane, as shown in Fig. 5.31 and on ORNL Dwg E-GG-C-L0603. (If the flattened faces had been mounted vertically, special precautions would have been required to eliminate the gas pocket tending to exist in the projection of the flattened section above the top of the pipe, an effect found to encourage porosity of the frozen plug.) The valve is surrounded by a 2-3/I x 2-in. long x 1-3/L-in. high shroud fabricated of 1/16-in.-thick INOR-8 sheet. One end of this shroud is welded to the process pipe and the other to a 4-in.-diam bellows about 13/16 in. long, having two convolutions, and fabricated of 20-gage INOR-8 sheet. The other end of the bellows is welded to the process pipe. The bellows allows for differential expansion due to the shroud operating at a lower temperature than the pipe wall. iy fs‘ T0 DRA\N TANKS L THERMOCOUPLES COOLING GAS THERMAL SHROUD INSULATION COOLING GAS A ’-- m;é \ - ‘,'-‘."'. '{ I} il "" ALY ) TR o CLOPREAEE A ¥ '0'.‘; \ ot~ ‘ %l \ A R WO B OO0 BT OB i COOLING GAS OUTLET FIG. 5.31. FREEZE VALVE IN LINE THERMOCOUPLE 103 BELLOWS N UNCLASSIFIED ORNL-DWG. 64-6898 ) To REACTOR —— i /f.\\\\(\\\\\\‘\i\\\\\‘\-\\\\\‘\(\\\\q\\@.?. _________ A VESSEL ./V AT — T %" 0.D. TUBE | o H ' “THeErRMocoupLe > !%" DRAIN LINE ' SHEATHED THERMOCOUPLES 196 The cooling gas enters the shroud from the side through a 5/h-in. s OD tube, and leaves through a similar pipe on the opposite side. The shroud is made concave on the top and bottom, as shown on ORNL Dwg E-GG-C-L40603, to increase the gas velocity and improve the heat trans- fer in those areas to obtain more rapid freezing of the salt plug at the center of the flow area. The freeze valve and shroud assembly are enclosed in a 20-gage stainless steel box about 8 in. wide x 5 in. high x 6 in. long, filled with Fiberfrax wool thermal insulation. (See Section 5.6.6.3.) - Two sheathed thermocouples are installed on the top outside flat- tened face of the valve, the sheathes passing through sleeves in the side plates of the shroud. Two thermocouples are also located on the top shoulder of the valve opposite the bellows end, and two couples are located on top of the pipe immediately adjacent to the bellows, as shown on ORNL Dwgs D-HH-B-4O543 and E-GG-C-40603. A Calrod heater, 0.315 in. diam with Inconel sheath, of 1500-watt capacity, is formed into a saddle shape and fits over the top of line 103 between the freeze valve box and the electrical connection to the line used for resistance heating between the reactor and the drain tanks. The saddle-type heater is removable with special tooling from above through a special standpipe arrangement, as shown on ORNL Dwg D-GG-C-L40604. The heater may be needed to prevent the pipe from be- coming too cool in the vicinity of the electrical connection lug, and is not directly assoclated with operation of the freeze wvalve. - The valve can be frozen by the 68 scfm jet of cooling gas in less 115 When the temperature of the shoulders of the wvalve - than %0 minutes. reaches about 6800F, the cooling gas flow is reduced to about 15 scfm; at 65OOF all gas flow would be cut off. When the temperature rises slightly above 6500F, the holding air would be resumed and if the temper- ature reaches 850°F the blast air flow of 68 scfm is again turned on. 5.6.5.5 Freeze Valves 104, 105 and 106. These freeze valves are located in the fuel-salt drain tank cell in the 1 1/2-in. salt transfer lines. One or more are thawed when salt is to be transferred, + L . 197 or when flush or fuel salt is being circulated in the reactor system, but are deep frozen at all other times. S The flattened sections on the process piping for these valves are essentially as described for FV-103, above, except that the flat sides are mounted in the horizontal plane. The general featureé of the cooling gas shroud, or box, are indicated in the sketch, Figure 5.34, The cross sectional»shapes of the shroud and/the process plpe at the center of the freeze valve are very similar. The shroud is 2-1/8 in. long, measured along the axie of the pipe, and has maximum overall dimensions of 2-5/16 in. high and 3-7/8 in. wide. The end pieces are fabricated of 1/8-in.-thick INOR-8 plate and are welded - to the process pipe. The outside shell, which is welded around the end pieces, consists of two layers of 0.024-in.-thick INOR-8 shim stock separated by two thickness of 1/8-in,-thick Fiberfrax in- sulating paper, Type 970-H. Additional details are shown on ORNL Dwg D-GG-C~-55509. The cooling gas is introduced at the bottom of the shroud through 1/2-in. OD x 0.042-in. wall thickness INOR-8 tubing. The gas circulates inside the shroud around the ffeeze valve section and leaves through a similar 1/2-in. OD tube at the bottom, the inlet and outlet openings being separated by a 1/8-in.-thick baffle. The inlet gas tubing has a 6-in.-long, 316 stainless steel, corrugated flexible connector welded in it to provide for relative movement of the process pipe and the-gas supply line. The~gaS-discharge pipe terminates about 8 in. below the freeze valve, ‘the gas discharging into the cell atmosphere. The thermocouple leads are brought into the shroud through:the exit gas tube. Two chromel—alumel, minersl-insulated thermocouples with 1/8-in. OD Inconel sheaths are applied to built-up pads on the top of the center section, os.indicated in Figure.5.32.. Two thermo- couples are also attached to pads on top of each shoulder outside the cooling gas shroud. _ ' ‘, _ | The cooling gas shroud: is enclosed in the removable heater- insuletion units for the process lines, see Section 5.6.6, following. The 3/4-in.-thick flat-plate ceramic heaters (Cooley Electric Mfg. Corp., 198 Indiangpolis) are arranged on the sides . .and top of the procéss piping, are attached to the insulation assembly and are removable with it. The heaters at FV-104 consist of two sections, FV-104-1, made up of six heater elements with a total capacity of 2.4 kw (at 230 v); and FV-104-3, containing three elements with a total capacity of 2 kw (at 115 v). The heaters at FV-105 are arranged in three sections: FV-105-1 has six heater elements with total capacity of 2.4 kw (at 230 v), FV-105-3 has three heaters and a total capacity of 2.0 kw (at 115 v), and FV-105-4 has three heaters with total capscity of 1.95 kw (at 115 v). Freeze valve 106 has two heater sections: FV-106-1 has six elements and a total capacity of 2.0 kw (at 230 v), and FV-106-3 has three elements and a total capacity of 2.0 kw (at 115 v). As shown on the Mirror Insulation Company5Dwgs G-118B and G-118¢C, the heater plates are not applied for a distance of about 2 in. along the pipe at the cooling shroud, due to the lack of space. Sufficient heat is obtained by conduction along the process pipe to thaw the freeze valve. Also, see ORNL Dwg E-MM-A-51660. Heaters on the piping adjecent to FV-104, 105 and 106 are on at all times during reactor operation. A valve is thawed by cutting off the cooling gas flow. While freezing and thawing times are not critical in the operation of the MSRE,]'15 the observed time is less than 10 minutes with electric power available and less than 20 min when relying only on the residual heat in the systemn. A cooling gas flow of 15 scfm through the cooling shroud will freeze a salt plug in less than 30 minutes. When the temperatures of the shoulders of the valve are indicated to be less than 750°F, the cooling gas flow is reduced to about 3 scfm to hold the plug frozen. Should the temperature climb to about 820°F, the high flow rate will be resumed. If the temperature falls below 650°F, the gas flow will be stopped altogether to prevent the formation of too large a frozen zone. | 5.6.5.6 Freeze Valves 107, 108, 109, 110, 111 and 112. These freeze valves are installed in salt transfer lines in the fuel drain tank and fuel processing cells. Although direct maintenance is not possible in the drain tank cell, FV-107, 108 and 109 were not provided fa UNCLASSIFIED ORNL-DWG. 64-6899 ———— ALL THERMOCOUPLES NOT SHOWN. N, s 7 T \\-‘\’ < \\\ ~\\ \\k’ N \i \\ NOTE N THERMAL INSULATION COOLING GAS SHROUD THERMOCOUPLES A\ A \h A / 7 H 1! ! ! | § i ’..--..._.._7,—,‘___ / / s / - s M COOLING GAS INLET COOLING GAS OUTLET THERMOCOUPLES FIG. 5.32 FREEZE VALVE IN LINES 107,108,109 & |10 66T 200 NOTE o o ALL THERMOCOUPLES & TF=] NOT SHOWN. -~ ~ o=l 1 g7 S s e .{ ”~ ™ Al 41178 N él v ’:- ! = i THERM oN : INSULA 4 i /E N ,/,’:3, |= T A %\ 1 COOLING GAS—* INLET \; i ~ ~ | R ~ 1 ) | T S 4 ~ ~ COOLING GAS QUTLET THERMOCOUPLES FIG. 5.33. FREEZE VALVE IN LINES & 112 ‘w o §y S UNCLASSIFIED ORNL-DWG. 64-6200 B 2 . . - . ~ - o 201 with removable heater and insulation sections, as were FV-10L4, 105 and 106, which are also in the drain tank cell, because the non-removable type heaters were simplier and more economical to install. Lines 107, 108 and 109 are not essential to reactor'operation, and, in most cases, if a line fails to thaw properly, an alternate route can be used for transfer of the salt. A further consideration is that the heaters at FV-107, 108 and 109 are seldom used, the valves remaining in the deep frozen condition for long periods, and could be reasonably assumed to require no maintenance during the life of the MSRE. The freeze valves in the sealed drain tank cell use cell atmosphere gas for cooling whereas FV-110, 111 and 112 are in the fuel processing cell and use air as the coolant. As may be noted in Figure 5.32, freeze valves 107, 108, 109 and 110 have pots, or reservoirs, on each side of the valve. Freeze valves FV-11l and 112 have a pot on one side only as shown in Figure 5.33. The transition from l/2-in. pipe size to the l-l/2-in. NPS freeze valve section is made at the reservoirs. The dimensions of the flattened section of l-l/2-in. pipe are as described for FV-103%, Section 5.6.5.4, above. The construction of the cooling gas shrouds, the freezing and thawing times, and the thermocouple locations, are essentially the same as listed for FV-10h4 in Section 5.6.5.5, above, and in Table 5.11. The heat for thawing of freeze valves 107 through 112 is conducted along the pipe walls from the permanently-installed curved-plate ceramic pipe line heaters on each side of the freeze valve section. The pipe line heaters are described and listed in Section 5.6.6, following. 5.6.5.7 Freeze Valves 204 and 206. These two freeze valves are located in the drain and fill lines for the coolant-salt system and thus are not part of the primary circulating system. They are described here, however, to complete the section on freeze valves. Both freeze valves are located in the coolant cell, and both must be thawed to completely drain the coolant-salt circulating system. The flattened section of l;l/E-in. pipe at each freeze valve is the same as described for FV-103, Section 5.6.5.4. The 1500-w UNCLASSIFIED ORNL-DWG. 64-6901 THERMAL NOTE INSULATION ALL THERMOCOUPLES NOT SHOWN. ERMOCOUPLES . NN ., o CERAMIC ELECTRIC RESISTANCE HEATING ELEMENTS A N . CERAMIC ELECTRIC RESISTANCE CALROD HEATING ELEMENT HEATER HEATERS LEADS HEATERS COOLING AIR THERMOCOUPLES INLET COOLING AIR INLET FIG. 5.34. FREEZE VALVE IN LINES 204 &8 206 1" ! PN c0e 1 ! ' v 203 (at 110 v) Calrod heater unit is identical to the one used on FV-103 (see ORNL Dwg E-GG-C-L0603) except that the flat sides of the valves are-in the horizontal plane and the heaters are applied from the side, FV 204 and 206 being approchable for direct maintenance a short time after reactor shutdown. Curved-plate ceramic heaters are applied to the process piping on each side of the freeze valves, as shown on Dwg E-MM-Z-L47489. The thermal insulation on the outside of the line heaters is 3-in. of Careytemp 1600°F (Philip Carey Mfg. Company). No thermal insulation is used around the center sections of the freeze valves. No cooling gas shrouds are used. The cooling air is supplied through the B/M-in. lines 906 and 907, each of which branches at a tee beneath its freeze valve into two 3/8-in. steel pipes discharging about 5/8 in. from the top and bottom outside surfaces of the valve. See ORNL Dwg D-GG-E-41885 and Figure 5.35. Two thermocouples are welded on the side of the center of the flattened section of each valve, and two are applied to each shoulder. In addition, single couples are installed about 5 in. upstream and downstream of each valve, and two are on the reservoir pot located between the two valves. Thermocouple locations are shown on ORNL Dwg D-HH-B-40543, | o When the valves are to be thawed the cooling air supply is stopped and the center héater is turned on until the temperature measured at the center of the valvefis_greater than 1,000 - l,lOO°F. A frozen valve will thaw'iniieSS than 5 minutes. Without electric power the valves will thaw in less than 25 min, by conduction of heat, and will remain thawed for 30 min or more. .The center heatef, if on, is turned off before the valves are to be frozen. A coolihg-flow of 25 scfm'of’air will freeze a solid 'salt plug in less than 15 min in either FV 20k or 206. After the temperatures of the,shoulders of the valves reach about T50°F, the air flofi is reduced to a holdihg fateof 5 scfm. Should the tempera- ture of the center of the valve climb above ‘750°F the high air flow rate will be resumed. Below 650°F the valves are deep frozen and all air flow is cut off. L 204 FEMALE DISCONNECT ¢ TERMINAL BOX WITH MALE DISCONNECT REMOVABLE LAP JOINT CLOSURE Fig. 5.35. Removable Heater for 5-in. Pipe. ‘. UNCL ASSIFIED - PHOTO 70759A i f» b £ - & 205 5.6.6 Pipe Insulation and Heaters 5.6.6.1 General Description and Design Considerations. All salt-containing lines ifififhe MSRE are thermally insulated and provided with electrical heaters capable of maintaining the salt above the ligquidus temperature of 850°F. The heaters can be broadly classified into the removable and permanent types. The former are defined as those with the thermal _insulation and heaters arranged into an integral unit that can be re- moved and replaced by remotely-operated tooling as illustrated in Figure 5.35. The types, which use more conventional materials and methods of installation, are defined as those which would require direct approach for maintenance, although in some instances this would not be possible because of the activity level. All such per- manent heaters have spare heating elements installed and connected ready for use except for minor out-of-cell changes. Some of the heaters at the more inaccessible sections of piping have excess installed capacities so that they may be operated at re- duced voltage to promote longer heater l1ife. In general, vertical lines require about twice the heater capacity needed for horizontal pipes. The heaters are supplied with either single phase 115-v, single phase 208 and 230-v, or three-phase 208-v power, and some are connected in series and some in parallel, all as dictated by the heater requirements and the nature of the electrical supply equip- ‘ment alréady'on hand in Building 7503'at the start of the MSRE project. The maximum amperage, total power per heater, and the watts per £t of pipe length, as listed on the drawings and in Table 5.12, are béséd bn the“current-carrying'capaéityiof the electrical supply eqfiipmént and not-fipon the power that can be délivered to each pipe section without excessive hefifing of the materials. Such values mist be determined in the field during preliminary testing. of the reactor. o R AR : ' The thermal insulation can be divided into (1) the metallic, multiple-layéf reflective type, and (2), the low thermal conductivity ceramic fiber or expanded silica types. The reflective insulation 206 has the important characteristic of not dusting, and is used on all salt lines in the reactor cell, with the exception of line 103. The low conductivity types, as installéd, have a lower heat loss per ft of pipe. In selecting the materials, consideration was given to the resistance . to radiation damage, accumulation of long-lived induced activity, and to compatability with other materials in the system. Almost all the removable heaters use reflective type insulation. (The removable heaters at FV-104, 105 and 106 use the ceramic fibef type). Almost all per- manent heaters use expanded silica insulation. - At least one thermocouple is provided on the piping for each heater unit. Anticipated "cold spots" in the piping have additional couples. With the exceptions noted below, all the pipe line heaters on the portions of the fuel and coolant-salt piping within the reactor ceil are of the removable type. See Table 5.12. These heaters have resistance wire embedded in flat ceramic plates and are arranged at the top and sides of the piping. All the removable heaters in the reactor cell use multi-layer reflective type insulation. The vertical leg of piping in line 102 just below the primary heat exchanger is very difficult to reach with remotely-operated tools. The heaters for this section are a tubular type strapped to the pipe. A set of spare heater elements is also installed. This portion of piping would be removed with the heat exchanger if repairs are needed. These heaters on line 102 have reflective: > type insulation. | The portions of lines 100 and 102 that pass through the thermal shield of the reactor also have removable type heater-insulation units, as described above, but since access to them would require lifting of the thermal shield plugs, each ceramic heater element is provided with a duplicate set of resistance wires in the plates. Line 103 is heated by passing an electric current through the pipe wall itself. Non-removable, expanded silica insulation is applied over the resistance-heated length, including the portion inside the drain tank cell., See Section 5.6.6.2, following. , ‘ * > 207 Lines 104, 105 and 106 in the fuel-salt drain tank cell have re- movable heater-insulation units such as those used in the reactor cell. The heaters on lines 107, 108 and 109 in the drain tank cell see little service since the freeze valves in these lines are deep frozen most of the time., In most part, these three lines have permanent tubular-type heaters. Although they should be maintenance-free during the life of the MSRE, duplicate spare heaters are installed. The portion of the fuel-salt transfer line 110 located in the drain-tank cell also has permanent tubular-type heaters, but, since this line is used more often than 107, 108 and 109 (although still infrequently), it is provided with two sets of spare heaters in each pipe section. The section of line 110 in the fuel processing cell, and lines 111 and 112 in this cell, have permanent heaters and expanded silica in- sulation. The equipment in the fuel processing cell will require decontamination before approach for direct maintenance, therefore spare heater elements are provided. | | Some sections of the piping in lines 107 through 112, such as adjacent to the freeze valves and at the drain tank furnace walls, require a greater concentration of heat than is available from the tubular heaters. Permanent curved-plate ceramic heaters are used at these points.* See Table 5.12. Direct maintenance can be used on the coolant-salt piping in the coolant cell a short time after reactor shutdown. Tubular-type heaters are strapped to the piping and covered with expanded silica insulation. The penetrations through the reactor containment vessel wall for the coolant salt lines 200 and 201 are provided with ceramic plate heaters having spare heating wires. These heaters, and the low-conductivity thermal insulation used with them, can be removed by‘manipulation from £he éoolant cell end of the pene- tration, but they cannot be as readily approached for direct maint- enance as the other coolant cell equipment. *The energy input on & 1/2-in. NPS horizontal pipe is about 750 watts/ft from a ceramic plate type heater and about 200 watts/Tt from a tubular type. 208 5.6.6.2 Pipe Heaters. The process piping is heated by three methods: (1) ceramic plate and (2) tubular type heaters applied to the piping, and (3) resistance heating of the pipe wall with an electric current. The heaters are listed in Table 5.12 for each of the sections of piping. The coolant-salt piping has been included in this section to complete the discussion of heaters and insulation.. (1) Ceramic Plate Heaters. These heaters consist of nichrome resistance wire embedded in a ceramic plate about 3/4 in. thick to form either flat plates 1/2-cylinder, or 1/k-cylinder shapes curved . to fit the pipes. These "Thermoshell" elements, manufactured by the Cooley Electric Manufacturing Company (Indianapolis) are used in a variety of sizes, but the flat plates are typically about 5 in. wide x 12 in. long. (See heater schedules on ORNL Dwgs E-MM- A-51601 and 40833, 51661). As indicated in Table 5.12, some ceramic plates have spare resistance wires. The ceramic plates are largely composed of sodium atoms, but small amounts of thorium, leading to 25jPa. after irradiation, can 'cause significant activity in the elements after long exposure. The resistance heating wires are primarily nickel and chromium with small amounts of cobalt. Induced activity, due to formation of 5800 from the nickel and 6000 from the natural cobalt, probably will re- strict direct handling of heater units removed from the reactor cell.118 . (2) Tubular Heaters. These heaters are of the "Calrod" type, - as furnished by the General Electric Company. The Inconel sheaths are 0.315 in. OD. The lengths and capacities vary, as shown in Table 5.12. The No. 12 wire extension leads are insulated with ceramic beads, as shown in detail on ORNL Dwg E-MM—B-5167. (3) Resistance Heating. Drain line 103 is heated by passing a heavy electric current at 18 v through the pipe walls. The 25-kva h20/18-v transformer to supply the current is located in the south- west corner of the drain tank cell. Leads from this transformer are connected at about midpoint in the line, which is in the drain tank cell near to the transformer; The current flows from this connection k;; to each end of the line. Electrical connections are made about 12 in. L44 Table 5.12. MSRE Pipe Line Heaters Maximum Values Based on Elec. Heater Supply System Equipment Heater Length Number Total Watts Number Location (in.) Typea Heaters Voltsb Amps Watts per ft Remarks REACTOR CELL® H100-1 R outlet to FF1l00 11-7/16 c 230 16.5 3800 4000 Duplicate spare installed H100~2 FF-100 to FP furnace 5-3/8 C 115 24,3 2800 6250 - H101-1 FP to FF-101 27-13/16 C 6 208, 13.9 5000 2000 Connected with H102-% H101-2 FF-101 inlet 13-1/2 C 230 17.4 Looo 3550 - H101-3 AX inlet 5-1/2 C % 115 2%.5 2700 4100 - H102-1A Vertical line from HX 60 T 212 ) 2120 1275 Duplicate spare installed H102-1B Vertical line from HX 52 T 3 212 % 28.0 1840 1275 Duplicate spare installed H102-1C Vertical line from HX 56 T 212 ) 1970 1275 Duplicate spare installed H102-2A Horizontal line to 20 c 6 208,3p 11.1 4000 2400 - FF-102 H102-2B Horizontal line to 20 C 6 208,3¢ 11.1 4000 2400 - Fr-102 H102-3 Horizontal line to 2l C 6 208,3p 11.1 L4000 2000 Connected with H101-1 FFr-102 H102-4 FF-102 inlet 8-3/16 c 3 230 11.7 2700 4000 - H102-5 FF-102 to R 11-7/16 c 3 230 16.5 3800 4000 Duplicate spare installed H200-1 Adjacent cell wall 15 C 3 230 17.4 L0oo - H200-2 Cell wall to FF-200 24 C 6 208,30 11.1 L4000 2000 Connected with H200~3% & 4 H200-3 Cell wall to FF-200 30 C 6 208,30 13.9 5000 2000 Connected with H200-2 & 4 H200-4 Cell wall to FF-200 N C 6 208,3p 11.1 4000 2000 Connected with H200-2 & 3 H200-5 Cell wall to FF-200 27 c 6 208,5¢ 1%.9 5000 2200 Connected with H201-8 H200-6 Cell wall to FF-200 30 C 6 208,5¢ 13.9 5000 2000 - H200-7 Cell wall to FF-200 30 C 6 208,3f 13,9 5000 2000 - H200-8 Cell wall to FF-200 30 c 6 208,30 13.9 5000 2000 - 602 i) Table 5.12, (continued) Maximum Values Based on Elec. Supply System Equipment Heater Heater Length Number Total Watts Nurber Location (in.) Type Heaters Volts Amps Watts per ft Remarks H200-9A Wall to FF-200 20 o 6 208, 3¢ 11.1 hooo 2400 Connected with H200-9B, H200-9B Wall to FF-200 20 c 6 208, 3@ 11.1 4oo00 2400 - 4A & 4B H200-10 Wall to FF-200 2k ¢ 6 208, 3¢ 11.1 L4000 2000 Connected with H201-3 H200-11 Ad jacent FF-200 23-3/16 ¢ 6 208 19.2 Looo 2075 - H200-12 HX inlet lo c 3 115 26.9 3100 7500 - H201-1 Ad jacent FF-201 23-3/16 C 6 208 19.2 L4000 2075 - HX side. H201-2 Ad jacent FF-201 11-3/16 C 3 230 16.1 3700 2000 - HX side. H201l-3 FF-201 to cell wall 30 C 6 208, 3 1%3.9 5000 2000 Connected with H200-10 H201-4A FF-201 to cell wall 20 c 6 208, 33 11.1 4000 2k00 ) Connected with H200-9A, H201-4B FF-201 to cell wall 20 c 6 208, 3p 11.1 4oc00 2400 ) Connected with ggo%—gfi, H201-5 FF-201 to cell wall 30 o 6 208, 3¢ 13.9 5000 2000 - 98 & OA H201l-6 FF-201 to cell wall 2l C 6 208, 3¢ 11.1 4000 2000 - H201-7 FF-201 to cell wall 30 c 6 208, 3¢ 13.9 5000 2000 - H201-8 FF-201 to cell wall 30 C 6 208, 3¢ 13.9 5000 2000 Connected with H200-5 ‘H201-9 FF-201 to cell wall 25 c 6 208 24,0 5000 2000 - DRAIN TANK CELL LINE HEATER UNITS® Hio4-1 At FFT 10-1/2 N 3 115 11.3 1300 1500 - H104-2 FFT to FV-10h4 30 ¢, 6 230 19.6 L4500 1800 - H104-3 FFT to FV-10h4 30 Cy 6 230 26.0 6000 2L00 - H104-4 At FV-10k4 30 Cy 6 230 19.6 4500 1800 - H104~5 FV-104k to line 103 10-1/2 Cy 3 115 14+.8 1700 1950 - Hi04-6 FV-104 to line 103 12 3 115 17.4 2000 2000 - H104-7 At line 103 30 8 230 26.0 6000 2400 Duplicate spare installed 0T1¢ Table 5.12. (Continued) Maximum Values Based on Elec. Supply System Equipment Heater Heater Length Number b Total Watts Number Location (in.) Type Heaters Volts Amps Watts per ft Remarks H1.05-1 At FD-2 10-1/2 Cy 3 115 11.3 1300 1500 - H105-2 FD-2 to FV-105 30 c, 6 230 19.6 L4500 1800 - H105-3 FD-2 to FV-105 30 Cy 6 230 17.4 kooo 1600 - H105-4 At FV-105 12 Cy 3 115 17.4 2000 2000 - H106-1 At FD-1 10-1/2 Cy 3 115 11.3 1300 1500 - H106-2 FD-1 to FV-106 30 ¢, 6 230 19.6 L4500 1800 - H106-3 At FV-106 28 Cy 6 230 26.0 6000 2500 - H106-4 FV-106 to line 103 12 c, 3 115 8.7 1000 1000 - H107-1 At TFT b Co 2 57.5 4. 35 250 50 Duplicate spare installed H107-2-1 FFT to FV-107 62 T 1 ko ) 7.26 750 187 Duplicate spare installed H107-2-2 FFT to FV-107 32 T 1 1ko ) 280 187 Duplicate spare installed H107-3A,3B Ad@acent flange h 02 2 57.5) 8.7 250 750 Dupl%cate spare ?nstalled 3C, 3D, Adjacent flange L Co 2 57.5) 250 750 Duplicate spare installed H108-1 At FD-2 4 Cs 2 57.5 4,35 250 750 Duplicate spare installed H108-2-1 FD-2 to FV-108 L T 1 140 ) 460 185 Duplicate spare installed H108-2-2 FD-2 to FV-108 50 1 140 % 9.25 550 185 Duplicate spare installed H108-2-3 FD-2 to FV-108 32 1 140 ) 275 185 Duplicate spare installed H108-3A,3B Adjacent flange b C, 2 57.5) 8.7 250 750 Duplicate spare installed -3C,3D Adjacent flange L Co 2 57.5) 250 750 Duplicate spare installed H109-1 At FD-1 Y Co 2 57.5 4,35 250 750 Duplicate spare installed H109-2-1 FD-1 to FV-109 4l T 1 ko ) 460 185 Duplicate spare installed H109-2-2 FD-1 to FV-109 50 T 1 140 ; 9.25 550 185 Duplicate spare installed H109-2-3 FD-1 to FV-109 32 T 1 140 ) 275 185 Duplicate spare installed H109-3%A,3B Ad@acent flange Y CE 2 57.5) 8.7 250 750 Dupl?cate spare %nstalled -3C,3D Adjacent flange L Co 2 57.5 250 750 Duplicate spare installed T1C Table 5.12, {continued) Maximum Values Based on Elec, Supply System Equipment Heater Heater Length Number Total Watts Number Location (in.) Typea Heaters Voltsb Amps Watts per ft Remarks H110-1-1 FV-108 to 1line 110 50 T 1 140 550 185 Duplicate spare installed H110~-1-2 FV-109 to line 110 50 T 1 140 1 7.9 550 185 Duplicate spare installed H110-2-1 AdJjacent FV-107 g8 T 1 156 ) 1600 230 Two duplicate spares H110-2-2 FV-107 to cell wall 98 T 1 156 g 28.0 1600 230 Tigsziéiigate spares H110-2-% FV-107 to cell wall Th T 1 156 ) 1150 230 installed H110-3-1 FV-107 to cell wall s T 1 230 ) 2500 500 Two duplicate spares H110-3-2 At cell wall ' T 1 230 3 Y 50 se0 installed COOLANT CELL LINE HEATER UNITS® H200-13-1 CP to sleeve 86 T 3 170,39 ) 5000 820 - H200-13-2 CP to sleeve 86 T 3 170, 3¢ g 5000 820 - H200-13-3 CP to sleeve 86 T 3 170,38 ) 35 5000 820 - H200-13-4 CP to sleeve 86 T 3 170, 39 g (80.8) 5000 820 - H200-13-5 CP to sleeve T 3 170,30 ) 820 - H200-13-6 CP to sleeve Ly T 3 170,3p ; 2000 820 - H200~-14A,B Wall sleeve 12 C, 2 230 600 600 Duplicate spare installed H200-14C,D Wall sleeve 12 Co 2 230 600 600 Duplicate spare installed H200-14E,F Wall sleeve 12 Co 2 230 i 10.4 600 600 Duplicate spare installed H200-1L4G,H Wall sleeve 12 Co 2 230 ) 600 600 Duplicate spare installed H200-15A,B Wall sleeve 12 02 2 115 13 1500 1500 Duplicate spare installed H201-10A,B Wall sleeve 12 02 2 115 13 1500 1500 Duplicate spare installed H201-114,B Wall sleeve 12 Co 2 230 ) 600 600 Suplicate spare installed H201-11C,D Wall sleeve 12 Co 2 230 3 10.4 600 600 Duplicate spare installed H201-11E,F Wall sleeve 12 Co 2 230 ) 600 600 Duplicate spare installed H201-11G,H Wall sleeve 12 Co 2 230 ) 600 600 Duplicate spare installed [AYY Table 5.12. (continued) Maximum Values Based on Elec. Supply System Equipment . Heater Heater Length Number o Total Watts Number Location _ (in.) Type Heaters Volts Amps Watts per ft Remarks H201-12-1 i T 3 150,3p 960 640 - H201-12-2 § Th T 3 150, 3¢ ; 3200 640 - H201-12-3 § g1 cve to radiator 56 T 3 150,30 ) 3800 640 - H2OL-12-4 . ) enclosure 86 T 3 150, 3¢ (85) 3800 640 - H201-12-5 % 86 T 3 150, 3¢ 3 3800 640 - H201-12-6 ) 86 T 3 150,3¢ ) 3800 640 - H201-13-1 In rediator enclosure 82 TR 3 230 ) 6.5 185 275 - H201-13-2 In radiator enclosure 82 TR 3 230 3 ' 1875 275 - H202-1-1 CR outlet pipe 50 T 3 11.9 1670 Loo Duplicate spare installed H202-2-1 CR to CP 62 T 3 170,5¢ %280 820 - H202-2-2 CR to CP Ly T 3 170,30 ) 2000 820 - H202-2-3 CR to CP 86 T 3 170,38 ) 35 5000 820 - H202-2-4 CR to CP 86 T 3 170, 3¢ % (80.0) 5000 820 - H202-2-5 CR to CP 86 T 3 170, 30 5000 820 - H202-2-6 CR to CP 86 T 3 170, 3@ 2 5000 820 - H203%-1A-1E¥ CDT Fill line 86 T 1 91 470 80 Duplicate spare installed H203-1F CDT Fill line L T 1 91 } 28 470 80 Duplicate spare installed H203-2 Fill line adjacent hi T 1 140 3.3 462 185 Duplicate spare installed to CDT H20k-1-1 Line 201 to FV-204 T T 2 201 ) i:it 1375 275 Duplicate spare installed H204-1-2 Line 201 to FV-20k T T 2 221 ) page 1375 275 Duplicate spare installed ¥ Typical for 1A through 1E. £1¢ Table 5.12. (continued) Maximum Values Based on Elec, Heater Supply System Equipment Heater Length 5 Number b Total Watts Number Location (in.) Type Heaters Volts Amps Watts per ft Remarks H20L4-1-3 Line 201 to FV-204 Th T 2 221 ) 1375 275 Duplicate spare installed H204-1-4 Line 201 to FV-20k T4 T 2 221 ; 28 1375 275 Duplicate spare installed H204-1-5 Line 201 to FV-204 56 T 2 221 ) 687.5 275 Duplicate spare installed H204-~2-1 FV-204 & FV-206 to CDT S0 T 3 132 0.0 510 170 Duplicate spare installed H20L4-2-2 FV-204 & FV-206 to CDT Th T 3 132 ’ 850 170 Duplicete spare installed H205-1-1 Line 201 to line 202 Th T 1 140 ) 1.2 1100 150 Duplicate spare installed H205-1-2 Line 201 to line 202 56 T 1 140 ; ’ 650 140 Duplicate spare installed H206-1-1 Line 202 to FV-206 62 T 2 2k ) 1120 280 Duplicate spare installed H206-1-2 Line 202 to FV-206 62 T 2 2Ll % 1120 280 Duplicate spare installed H206-1-3 Line 202 to FV-206 62 T 2 2kl ) 20,2 1120 280 Duplicate spare installed H206-1-4 Line 202 to FV-206 62 T 2 2kl g 1120 280 Duplicate spare installed H206-1-5 Line 202 to FV-206 32 T 2 2hl ) 1120 280 Duplicate spare installed 8 - removable heater unit with 3 segments (top and each side), ceramic elemenis. Duplicates have double element in each segment. C; - Removable heater unit, three flat ceramic elements (top and side). C2 - Fixed 90° curved ceramic elements, T - tubular heaters, non-removable.¥ TR - triangular, non-removable, bSingle phase unless otherwise indicated. * Each tubular heater includes a 7-in. non-heated length . at each end. The watts/ft is based on heated length, Reference Drawing E-MM-A-51601. dReference Drawing E-MM-A-51661. ®Reference Drawing E-MM-A-4%0833, »Te + 4 215 from the intersection with line 104 and just inside the reactor furnace on the other end. These connections are made by welding the lug to the pipe. The return electrical connection from the pipe ends is routed along the pipe as a single-No. 4 wire mineral-insulated cable 0.699 in. OD laid in special brackets about 4 in. above the line 103 insulation. See ORNL Dwg E-MM-A-562L0. 5.6.6.3 Thermal Insulation. Primary considerations in the selection of the pipe line insulation were the tendency of the materials to dust, the resistance to radiation damage and long- term activation, the thermal conductivity, and the presence of organic materials causing thermal deterioration or incompatability with other materials in the system. The multi-layer reflective type of insulation presents fewer dusting problems as compared to the low-conductivity type and is used almost exclusively in the reactor cell, although the stainless steel does contain some cobalt which will become radiocactive. The reflective units have a higher heat loss than the latter, however, as illustrated by the fact that horizontal sections of 5 in. pipe with reflective insulation require, on the average, about 2,000 watts/ft of energy input whereas similar pipe sections with ex- panded silica insulation require about 600 watts/ft. Some compromises were necessary in selection of the low-conduc- tivity insulation in that the good thermal conductivity and mechanical properties must be coupled with good resistance to spread of air borne contamination. Many mineral wool fibers contain significant cobalt or organic materials. Both the ceramic fiber and the expanded silica types selected for use in the MSRE are fired at 1200°F for about four hours before installation to drive off small amounts of volatile sulfur and chloride compounds. The types of insulation and the thicknesses used are listed in Table 5.13. (1) Reflective Insulation. Reflective insulation is used in all but a few of the removable heater units. The typical reflective unit, as manufactured by the Mirror Insulation Company (Lembertville, New Jersey) consists of a removable section, which surrounds the top and sides of the pipe, and a permanent bottom section which Table 5.13 THERMAL INSULATION ON MAJOR MSRE SALT PIPING Ni;E:r Lifi? ;;ge Location Ti?i;i::ifn::. Removable Type Remarks 100 5 Reactor cell Y Yes Reflective - 101 5 Reactor cell L Yes Reflective - 102 5 Reactor cell L Yes Reflective Vertical section beneath heat exchanger is non-removable. 103 5 Reactor and fuel DTC¥* 3 No Expanded silica |[Pipe is resistance-heated. 10k 1-1/2 Fuel drain tank cell L Yes Reflective Removable units at freeze 105 1-1/2 Fuel drain tank cell 4 Yes Reflective Iitzizt?fizf ceramic fiber 106 1-1/2 Fuel drain tank cell L Yes Reflective 107 1/2 Fuel drain tank cell 3 No Expanded silica 108 1/2 Fuel drain tank cell 3 No Expanded silica 109 1/2 Fuel drain tank cell 3 No Expanded silica 110 1/2 Fuel DTC and FPC* 3 No Expsnded silica 111 1/2 Fuel processing cell 3 No Expanded silica 112 1/2 Fuel processing cell 3 No Expanded silica 200 Reactor cell L Yes Reflective Insulation outside reactor cell 201 Reactor cell Y Yes Reflective isiz?ngzefiggiii:S:xP'd' silica. 202 5 Coolant cell b No Expanded silica 203 1/2 Coolant cell 3 No Expanded silica 20U 1-1/2 Coolant cell 3-1/2 No Expanded silica 205 1/2 Coolant cell 3 No Expanded silica 206 1-1/2 Coolant cell 3-1/2 No Expanded silica ¥ DIC = Drain tank cell; FPC = Fuel processing cell. *¥% For insulation details see ORNL Dwg E-MM-Z-56235, 9T¢ » 4 [ Ak" 217 is attached to the structure below the pipe and supports the top section. The heater plates are mounted in clips in the top section and are re- movable with it. Application of heat to only the top and sides was demonstrated to give satisfactorily even temperature distribution to the pipe contents. (The thermocouples for measuring the pipe wall temperature are, for the most part, attached to the bottom of the pipe). Starting at the inside, the first layer of reflective metal is 16 gage 310 stainless steel. The next layer is a sheet of pure silver 0.002 in. thick. The following nine layers are 321 stainless steel, 0.006 in. thick, arranged about 0.36 in. apart to provide a total thickness for the assembly of about 4 in. The outside surface is 18 gage 304 stainless steel. The removable units have a lifting eye at the top for handling with remote tooling. Life tests on the heater-insulation units covering six months of continuous operation at 1400°F indicated about a 10% increase in the heat loss due to change in the emissivity of the surfaces. The units showed good resistance to warping. (See p 30 ref 117). (2) Ceramic Fiber Insulation. "Fiberfrax", a product of the Carborundum Company (Niagra Falls) is used in the paper form in the freeze valve cooling gas shrouds, and in the blanket and bulk forms, at such points as the removable heaters at FV 104, 105 and 106. The ceramic fiber is about 51.2% A1203 and 47.8% 810, (by weight) and is recommended for temperatures up to 2300°F. The thermal conductivity of the blanket and bulk forms, when packed to & density of 6 1bs/ft5, is 1.2k Btu-in./hr-"F-fte at 1000°F and 1.89 at 14OO°F. The Fiber- frax paper used in the MSRE is Type 970-JH, which contains no organic binder. The paper has a thermal conductivity of 0.73 Btu-in./hr-ft2-°F at 1,000°F and 0.95 at 14OO°F. Activation analyses after 16 hrs in a newtron flux of T x 10T n/cm?—sec indicated that the lhOLa, with & LO-h half-life, and the 21‘1\13., with 15-h half-life measured 24 hours 2 3isintegrations per sec-gm and after irradiation, gave 2.72 x 10 1.87 dis/sec-gm, respectively. (See p 48 ref 108). These values indicate relatively good resistance to long-lived activation as compared to most inorganic, low-dusting, high-temperature insulation with low thermal conductivities. 218 (3) Expanded Silica Insulation. The expanded silica insulating material used in the MSRE is reinforced with inorganic fibers and has the trade name "Careytemp 1600", and is marketed by the Philip Carey Manufecturing Company (Cincinnati). The thermal conductivity is listed as 0.76 Btu-in./hr-fte-?F at 1,000°F. It is recommended for use up to 1600°F. It contains no inorganics, has a low hygroscopicity, and has | good resistance to dusting. Irradiation with neutrons for 16 hrs at 3 a flux of 7 x 10ll n/cm?-sec gave activations of 3,06 x 10” dis/sec-gm for the 40-h half-life lho.La., l1.12 x 101l dis/sec-gm for the 85-4 h6Sc, 5.02 x 107 for the 45-d *“Fe, and 8.57 x 10' for the 15-h e, (See p 48 ref 108). The insulation is applied to the piping over the tubular heaters in 1/2-cylinder molded shapes. It is then covered with asbestos -finishing cement and glass cloth, and a bonding adhesive to give a glazed finish. 5.6.6.4 Pipe Line Thermocouples. Since the pipe line thermo- couples are intimately associated with installation and operation of the heaters and the insulation, they are briefly described here. See Part II for a detailed description of the couples and the associated circuitry. Thermocouples are installed at the bottom of the pipe at each heater unit in the reactor and drain tank cells, and at the more important "cold spots." These spots, such as where pipe hangers are attached, may have lower than average temperatures and are there- fore of particular interest. As shown on Dwg E-HH-B-41713%, and in the thermocouple tabulation, ORNL Dwg D-AA-B-40511, many of the couples on the reactor cell piping are provided with spares. The coolant-salt piping also has a thermocouple at each heater unit and at some of the cold spots, but very few sfiares are provided since this piping is accessible for maintenance. An exceptioh to this is lines 204 and 206, which have spare couples at several points because of the importance of knowing the condition of the line. The penetrations of the coolant-salt piping through the reactor containment vessel wall have thermocouples on the bottom of the pipe spaced 12 in. apart. Each of these points is provided with a'spare_ couple. See ORNL Dwg E-HH-B-L40537. 219 In all cases, except as noted below, the thermocouples are mineral- insulated chromel-alumel wires in a 1/8-in. OD Inconel sheath. The couple junction is welded to the end of the sheath, as described in ORNL Spec MSR 63-40, and illustrated on ORNL Dwg D-GG-C-55509. An INOR-8 strip, l/h-in. wide x 0.015 in. thick, is shop-welded to the end of the sheath. With the exception of the 1/2-in. NPS piping, the ends of this strip are field-welded to pads, formed by welding, on the process piping. The ends of the couples on 1/2-in. piping are attached to a 1/8-in. high projection, formed by welding, on the out- side of the pipe, and the thermocouple sheath is strapped to the pipe. The same straps are used on all pipe sizes where it is necessary to fasten the sheath to the pipe at points other than at the ends. The INOR-8 banding material is l/h in. wide and fastened by a patented - "Wraplock" process. The duplex thermocouple sheaths described above are not used on the reactor vessel discharge piping at the fuel pump inlet, line 100. This set of three couples, and the associated spare, for measuring this important temperature, use two single-wire 1/16-in. OD Inconel sheaths, with the welded couple Jjunction made at the ends. Another set of these "safety" couples is used in line 202 at the radiator out- let. These single-wire couples also use 1/16-in. 0D sheaths but are not attached in the manner described above. Removable thermocouples are used in thermowells at this point (202 A-1 through D-1) and at the thermowell in the radiator inlet, line 201, to measure the At in the coolant-salt flow through the radiator. The thermocouples for;line 103 are a special case in that an “electric current flows through the pipe wall. The thermocouple . sheath is insulated from the pipe with ceramic beads exéept for about 1/4 in. at the end. The junction is an ungrounded type. 220 6. FUEL DRAIN TANK SYSTEM 6.1 General Description and Layout The MSRE primary circulating system is provided with two fuel drein tanks and & flush salt tank. The drain tanks are used to store the fuel salt vwhen it is dralned from the reactor. Either of the two drain tanks can store the entire salt content of the primsry circulating éystem. The flush salt tank is used to store the salt, which is circulated through the primary system to clear it of oxides and other contaminants before the enriched salt is added. (In addition, a fuel storage and reprocessing tenk is located 1in the fuel processing cell. This tank is described in the chemical processing portion of this report, Part VII.) The geometry of the fuel-salt drain tanks is such that the concen- tration of uranium in the MSRE fuel salt (see Table 2.1) cannot produce a critical mass under any conditions.119 A fourfold increase in con- centration would be necessary for criticality. Although studies have 1nd1ceted %2 that 1n equilibrium cooling of salt mixtures the last phase to freeze may contain about three times the uranium concentration in the original mixture, it is unlikely that the salt in the tanks will freeze, in that this would require an electric power outage of more than 20 hr, or that gross segregation of the concentrated phase could take place in a large-sized tank having so many thimbles on which initial solidification would take place., ®> The risk of criticality can be eliminated altogether by dividing a fuel-salt charge between the two drein tanks. One tenk will be kept empty for this contingency. | The two drain tanks and the flush salt tank are located in the drain tank cell, which is Just north of the reactor cell and connected to it by & short 36-in.-diam tunnel. The drain tank cell is constructed of heavily reinforced concrete, lined with stainless steel, and of the general dimen-~ - sions givéfi_in Section 4.3.2. The layout of the equipment in the cell is indicated in Figs. 4.4 and 4.5, and is shown in more detail in ORNL Dvg. E-GG-D~h1512l The arrangement was primarily influenced by thesreqnirement that“all maintenance operations be performed from overhead. Other con- siderations were the arrengement and flexibility of the piping, and the »; &7 i 4 & 1 221 relative elevations so that the reactor could drain by gravity. The drein line from the bottom of the reactor vessel, line 103, branches inside the drain tank cell into three lines which lead to the two drain tenks and to the flush salt storage tank. The fuel salt lines from these tanks, vwhich permit interchange of salt with the fuel process- ing afea, conbine into & single pipe, line 110, before leaving the drain tank cell. Each of the six lines mentioned has a freeze valve, as described in Section 5.6.5. The three branches of the reactor drain and £ill1 1line, line 103, reduce from 1-1/2-1n. sched-4O to l-in. pipe where each passes through the tank heating furnace and msekes a loop about 44 in. in diemeter, encom- passing about 340°, then enters the respective tank through the top head. This loop provides the flexibility needed to prevent pipe reaction forces due to thermal expansion from overly affecting the tank weigh cells used to judge the salt inventory. The loops also reduce the thermal stresses in the piping. Each tank is provided with an electrically heated furnace to main- tain the contents in a molten condition. Portions of the salt lines are provided with removable heater units and others have permanently installed Calrod-type heating units, as described in Section 5.6.6. The reactor drain line 103 is unique in the reactor system in that it 1s heated by passage of an electric current through the pipe wall itself. The drain line is heated by this method from & point at the reactor furnace wall to about 1 ft from the branch point inside the drain tank cell, a distance of ebout 6k £t, and requires sbout 17 kw. The 25-kva high-current elec- trical transformer, 420 to 18 v, is located in the drain tank cell (see ,__Section 19.7.3. 2) It has been- estimated that, on opening of the freeze valve in line 103, eleven to thirteen minutes are required for sufficient salt to drain from the primary system'to leave the reactor core reglon one~-fourth ¢ empty. 123 About 30 min is required for all the salt to drain, The two drain tanks are each provided with a heat removal system of 100-kw capaéity} This rate of heat dissipation is required for the first 80 hr after shutdown; sbout 50 kw is needed in 80- to 500-hr period.12lL The heat removal system consists of 32 thimbles, 1.9 in. in diameter, .y 222 immersed in the salt, and contelning bayonet tubes in which water is = eveporated. The gsteam from the tubes is collected in a steam drum located gbove each tank and piped to condensers outside the drain tank cell. The condensate is returned by gravity in & closed cycle. Transfer of the salt from one part of the systein to another is accom- plished by pressurization with helium gas. The gas 1s admitted at the top of the tanks through lines 572, 57k, and 5T6. All salt lines enter near the top of the tanks and have dip tubes to the bottom. The tanks are provided with weigh cells, as described in Pert IT. Provisions are made to cut the piping to permit replacement of the - drain tanks and freeze valves. ILines 104, 105, and 106 can be cut and . rejolined later by & brazed-on sleeve applied at the cut, using remotely operated tooling developed at ORNL. Thls special equipment is described - in Part X. Lines 107, 108, and 109 have one-half of a 150-1b, slip-on, ring-joint flange instelled in them. If & tank is removed, the line leading to the flange involved is cut on the tank side of the flange. The replacement tank can have & mating flange, or, as seems most likely, a blank flange can be bolted in place. If the line is blanked off, lines 104, 105, and 106 can be used to interchange the salt between the tanks by manipulation of the sppropriate freeze valves. The salt can then be transferred to the fuel storage tank through whichever of lines 107, 108, and 109 remain. A The steam drum liquld-level lines have cone-sealed, single~bolt, yoke * type discomnect couplings, which were designed and developed at ORNL, and are described in Part II. The gas lines have special 4-bolt flanged dis- connect joints installed in the horizontal position to facllitate remote maintenence. Detailed discussions of the maintenance procedures are given in Part X. | » 6.2 Flowsheet The process flowsheet for the fuel drain tank system is shown in Fig. 6.1 (ORNL Dwg. D-AA-A-40882), More detailed information is available . in the data sheets ,16 the line schedules ,17 and the thermocouple tabu- k,» lation, ORNL Dwg. D-AA-B-40511. The instruments and controls are described ’ = T ¢ CELL AR . COOLER #3 TO FUEL STORAGE _TANK r_ RRAIN TANK CELL " =19 SCFM . EACH—~—_ ELECTRICAL SERVICE AREA g DRAIN TANK CONDENSER DATA STRUCTURAL MATERIAL $10E TusE S1DE FLuID » TO REACTOR k} Q0T IN §-40-f TO0 VAPOR SYSTEM | CTw - o 1-40-88 | o FEED ) ' 79 GAL. WATER TANK (FWT-1} I 2.1 G INMENT - LOSURE NO. 304 85 STEAM WATER . 30sq, 1, 130PS5 F TO DUCT 937 VIA 840 LEVEL HALL 1 iooT-s8 HELIUM FROM LINE 501 l" — N ELECTRICAL SERVICE AREA $oor ni-ss CONTAIMMENT l ENCLOSURE NO. & DRAIN TANKX DATA DESIGN COOLING RATE 100 KW DRAIN TANK CELL AUTORESISTANCE REATING LUS I 1-155CFm FEED WATER 79 GAL. (Fwr-2) FLUSH TANKX 1 4 T35 FUEL PUMP TO AUXILIARY CHARCOAL BED L 2 DRAIN TANK CELL LEGEND P3G . —— NORMAL L /M | F VALVE POSITIONS ARE FOR NORMAL REACTOR OPERATION (H) 1S L HEATER CONTROL CIRCUIT & THIS DRAWING AS BUILT CHANGES THIS DESIGN 8 THE PROPERTY OF UNION CARBIDE NUCLEAR COMPANY — DLYVISION OF REFERENCE DRAWINGS DWS. 0. OAK RIDOR NATIONAL LABORATORY FUEL DRAIN TANK SYSTEM PROCESS FLOW SHEET M. E D-AA-A40802-C FIGURE 6.l NONE JOR . 4334,0 CARBIDE CORPORATION Tuirt STTves s e 204 in Part XI, and operating procedures are given in Part VIII. As shown in the flowsheet, Fig. 6.1, the fuel drain tanks, FD-1 and FD-2, and the fuel flush tank, FFT, are provided with 1 in./1-1/2-in. sched-40 lines 106, 105, 10k, respectively, to permit interchange of the fuel salt with the primary circulating system., Each of these three lines includes a freeze valve for positive, non-modulating control of the salt flow. The freeze valves are simply flattened sections of 1-1/2-in, sched - 40 pipe, which can be either heated by electric heating elements or cooled by & jet of cell atmosphere gas. The freeze valves are described in Section 5.6.5.5. | : The main Supply for the freeze valve coollng gas is the 2-in. sched-40 line 920, which branches into 3/k-in. lines 908, 909, 901, to supply each freeze valve. These three lines are provided with control valves and remote hand-operated regulators. A éhort, vertical cylinder of L-in. pipe is included in the salt piping on the tank side of each valve to form a reservoir which assures that the freeze valve section will be filled with salt. Either freeze valve FV-105 or 106 is always thawed during operation of the reactor to permit ready. drainage of the circulating system into one of the drain tanks. The other valve is operated in a frozen conditlon such that the heat stored in the adjacenf piping and heater box will cause the valve to thaw on loss of heater electrical power and coclant flow. All other valves on the drain tank system, FV-10T7 through 110, are deeply frozen and will remain éo even on loss of power. The times required for freezing and thawing are indicated in Table 5.11, Helium gas pressurization and vent lines control the transfer of salt from one part of the system to another. The tops of the draln tanks and flush tanks are vented to the top of the fuel-salt circulating pump bowl ‘through the 1/2-in. sched-lO pipes, lines Sil, 545, and S46. Each of these lines contains a pneumatically actuated control valve which can be positioned from a remote location by a hand-operated regulator. The three lines combine to form 3/h-in. line 521 leading to the pump bowl. This vent line not only permits transfer of the cover gas as the salt is belng exchanged between the primary circulating system and the storage -y & i - 225 tanks, but provides a large gas "cuchion" so that the overpressure in the pump bowl can be more evenly maintained.’ The gas line from the top of each tank- is connected to the charcoal beds through lines 573, 575, and 577. These lines contain control valves with remote hand regulators and combine to form 1/2-in. line 561 leading to the off-gas system. - | Helium for the cover gas and pressurization is supplied at about 4O psig through the 1/2-in. line 517 to-the pressure control valve PCV-51T, which delivers the gas at about- -Sorps:lg._.'bo the branch-pipes, lines 572, 57k, is installed upstream of PCV-517 t0o limit the rate at which the fuel can be transferred to the reactor. When the reactor system is about two- thirds full, this rate is 1/2 £43 of salt per minute. The three branch lines have check valves. and-pneumatically-actuated control valves po- sitioned by hend regulators. The.three lines are also provided with pressure transmitters for the recorders and the alarm system. Vent lines 582, 584, and 586 from the transmitters contain floating diaphregm seals vhich would store any ges that might escspe a lesking transmitter. These lines vent to line 588, a 1/h-in. OD tube, leading to the radiation monitors RIA 596A and 59613, and then to line 937 and the off-gas dis- charge stack. e ~ Decay heat 1s removed from the drained fuel salt in FD-1 and FD-2 by bayonet-type, boiling-water cooling :bubes. The steam drum, or dome, above each drain tank separates the weter.from the steam-water mixture dis- charged from the tubes, and recycles. the-water to the tubes. - The saturated steem 1s transported by 3-in. sched-hO stainless steel pipes, "11nes_ 80k end 805, to condensers, DrC-1-and DI‘C-E ‘located in the west tunnel ares. The condensers are cooled by.procegs. water c:!.rculated through lines 810 end 811, and 812 and 813.. Condensate flows by gravity from the condensers to. feedwater storage tanks _located benea‘bh the condensers via 1-in. lines 878 and 879 ‘Water 1s recirculated- £rom the feedwater tenks by gravity feed to the steam drum through l-in, sched-koO stainless steel pipes , lines 806 end 807. Valves ICV-806 and LIC-807, for these valves are connected to the steam drum but are located in the transmitter room. The maximum rate of feedwater flow is sbout 2.1 gpm. When the decay heat generation " the decay'hea£ removal system in Section 6.3.3, following. , QE; 226 is low, intermittent operation of. the..cooling system 1s required. To . - reduce the cooling rate to:zero; the water. flow 1is shut off and the tubes allowed to evaporate to dryness. -Steam from-the X-10 plant is condensed to provide water for the heat removal system. Both the condensers and the feedwater tanks are vented to the vapor condensing system.through lines 808, 809, 888, and 889. These lines join to form 1-in. line 338, vhich leads to line 980 connecting the vapor-condensing system to the primary containment. The top of each steam drum 1s vented to its respective condenser through lines 804 and 805. - ' - The 1/2-in. sched-i0 pipes, lines 107, 108, and 109, which dip to the bottoms of the flush tank, FFT, and the drain tanks, FD-1 and FD-2, are used to interchange salt between the tanks and the fuel processing cell. Each of these lines is provided with a freeze valve before they merge to form line 110, a 1/2-in. sched-4O pipe leading to the fuel storage tank, FST. The freeze valves and the Juncture with line 110 are shown on the fuel processing flowsheet, Fig. 6.2 (ORNL Dwg. AA-A-4088T) shown here for convenience. These freeze valves are equipped with the salt reservolrs at both ends of the flattened portion to assure salt in the valve at all times. The freeze valves are provided with thermocouples in an identical mapner with the valves on lines 10k, 105, and 106, described above., The 1 to 15 cfm (std) of cooling gas needed for the valves is supplied through lines 911, 912, and 913, which branch from line 920, previously mentioned. . " 6.3 Drain Tanks No. 1 and 2 6.3.1 Description Fuel drain tenk assemblies.No. 1 and 2, FD-1 and FD-2, are alike except_for,the nozzle orientations {see general assembly drawings ORNL Dwg. E-FF-A-L4O455 and E-FF-A-4OT31). A complete assembly consists of the tank-with supporting-skirt, thimbles, and steam drum with attached bayonet-type cooling tubes, as illustrated in Fig. 2.6. The tank gupports are described in Section 6.3.5 and the steam drum and other portions of ABSORBER DATA CONTROL CIRCINT - — —— VALVE CLOSES IF BLOWER POWER FANLS verTe ver3 ver2 —2" ATER PRESSURE ABSOABER CUBICLE U ——— . PREMEATER LOCATED 1N INSTRUMENT BAY i T} Y T 5 PRENEATER PLP | . CAUSTIC SCRUBBER hesy i d e ~ sy SODIUM FLUORIDE TRAP . . {SFT} L ________x X ____x ___§ _______§ ] CAUSTIC SCRURBER DATA SODIUM FLUGQRIDE TRAP DATA AREA QUTSIDE 7503 WEST OF DTC AC HF TRAP H, CYLINDERS My OR 80, CYLINDERS e ] IV!NT 10 | ATMOS, T I caustic - { i pim REACTOR FLA DUCT 940 FROM F, AMALYZER HIOH BAY AREA ABSOLUTE FILTER 48Q.F1T. SPARE CELL P FUEL STORAGE TANK {F3T) DAMPER (. &) FUEL PROCESSING CELL CONTROL M | 40 PSIG HELIUM 0. PROM LINE 500 j-eo-ss N WATER ROOM ] DRAIN TANK CELL R S—— AREA WEST OF FPC FROM CCA3 IN BLOWER WOUSE -40-3 PUIL LOADNG & STORASE SYITEM INSTRUMENT APPLICATION DIAGRAM AEFIBICR SAVRNES swe, M, OAK FIDoE NATIONAL LABORATORY FUEL PROCESSING SYSTEM PROCESS FLOW SHEET DdAA-40087-D FIGURE €.2 228 The drain tanks are 50 in. in diameter and about 86 in. high, not including the steam dome, and hold about 80.2 ft3) of salt contained in the primary circulating loop. The tare weight of a drain tank, including the steam drum, etc., is TOOO 1lb. The maximum weight is sbout 17,000 1b. Other dimensions of the tanks are given in Table 6.1. " The top head of each drain tank acts as a tube sheet for 33 thimbles of 1-1/2-in. sched-40 INOR-8 pipe, about T7-1/2 in. long, which extend into the tanks to about the elevation of the lower head welds. All but one of the thimbles project about 1ll in. above the upper head. The re- maining thimble is for thermocoupies. The 32 thimbles are evenly spaced 127 on two circles concentric with the centerline of each'tank, 20 on the outer circle, and 12 on the inner one. The thimbles serve as recept- ~acles for the bayonet-type cooling tubes and have flared openings at the upper end to facilitate insertion of the bayonets. It may be noted that two independent barriers, the thimble wall and the bayonet tube | wall, separate the fuel salt from the water. The annular gas space between the two walls 1s open to the cell atmosphere, which is continu- ously monitored for the presence of fuel salt, water, and the products of their reaction. | The fuel transfer lines 108 and 109 enter the drain tanks through the upper head flange and extend downward to a cup at the center of the lower head., This cup, which 1s fabricated of a 2-in. INOR-8 pipe cap welded to the outside of thw lower head, makes it possible to remove essentially all the salt from the tank, Lines 105 and 106, which are used to exchange fuel salt with the primary circulating system, enter through the top head of each tank and extend dowfiward, with a bend at the lower end, to terminate approximately 2-5/8-in. above the lower head, and near its center. The lower end of each of these pipes is closed, and a segment of the pipe wall is cut away - at the bottom end to provide an opening which does not draw salt from the bottom of the tank. This leaves a "heel" of about 1/2 ft3 of salt below the inlet to minimize the likelihood of transferring any solids from the bottom of the drain tank into the fuel circulating system. €7 e A % 5 229 Table 6.1. Design Date for Drain Tenks No. 1 and 2 Fuel Drain Tenks (two) Construction material Height (without coolant headers), in. ~ Diameter, in. (OD) Wall thickness. in. Vessel Dished head Volume at 1250°F, £t Total (excluding coolant.tubes) Fuel (min., normal f£ill conditions) Gas blanket (mex., normel £ill conditions) Heel and runback (min.) Design temperature, °F Design pressure, psi Cooling method Cooling rate (design), kw Coolant thimbles Number Construction meterial size, in. L Concentric feed tube (INOR-8) Steém riser (INOR-8) -~ INOR-8 86 50 1/2 3/k 80.2 T3.2 7.0 o 1300 65 Boiling water in double wall thinbles 100 32 mOR"B . 1-1/2 in. sched-ho 1/2 in. OD by 000’-"2" in. wall 1 in, IPS eched-k0 230 The above~-mentioned interior fuel-salt piping is held in position inside the tank by restraining brackets fabricated of 1/4-in.-diam INOR-8 rod. A nozzle 1s provided in the top head of each tank for installation of the level probes, ID-1 and ID-2. The probes are the singlefpdint; | conductivity type, and indicate whether the salt level is ahove or below points merking 5% and 90% of the salt volume. | A 3-in. pipe nozzle st the center of the head serves as an inspection port and can also be used for installation of a salt sampler. The closure for this nozzle is an eight-bolt blind flange with an integrasl ring-joint gasket provided with leak detection openings. A 1/2-in. nozzle on the top head serves as & common connection for helium cover-gas venting and pressurization lines 572 and 573 on FD-1, and for lines 5Tk and 575 on FD-2. The lines are provided with a large loop encircling the top of the tank, in much the same manner as the drain lines, to provide flexibility. The nozzle, the- short length of connected piping, and the disconnect flange are of INOR-8. (Beyond this point the lines are fabricated of stainless-steel.) The four-bolt disconnect flange is a l-in. size, but is drilled for 1/2-in. NPS, with a side out- let to permit installation in a horizontal position and easy access to the bolting from above. The INOR-8 steam drum and salt-cooling bayonets are an integral unit. The 32 bayonets are-fabricated-of l-in. sched-t0 INOR-8 pipe, as shown in Figs. 6.3 and 6.4, A 1/2-in. OD tube on the inside of each bayonet serves as the downcomer for the entering feedwater. The l-in. bayonet size increases to 1-1/2-in. pipe size above the elevation of the thimble openings, and.a 1l-1/2-in. corrugated, flexible Inconel hose is weldéd to each. (The corrugations are covered with stainless steel braiding.) The other end of each hose.is welded to 1-1/2-in. nozzles at corresponding positions on the bottom of the steam drums. The 1/2-in. downcomers have‘stripwouhd TIhconel flexible hoses in the same relative position. This flexible arrangement provides for the differences in radial thermal expansion between the drain tank upper head and the steam drum.¥* The weight of the steam-and-water-filled bayonets is not imposed on thé flexible hose couplings but is carried by a plate on vhich a collar ¥See Part 1V, Ref. 15, Moyers, J. C., et al., Drain Tanks. L ” L » s 231 | i 1 | i | Unclassified Photo 39404 (X Fig. 6.3. Fuel Drain Tank Steam Dome Bayonet Assembly. 232 UNCLASSIFIED ORNL-LR-DWG 60838A1 STEAM QUTLET FLEXIBLE HOSE » BAYONET SUPPORT PLATE 3 v ¥ - - - . WATER INLET - STEAM DOME LOWER HEAD I | | i | | | :__ | | | | Fig. 6.4. Bayonet Cooling Thimble for Fuel Drain Tank. # 4% 1) 3 233 welded to each bayonet tube rests,. This 1/L-in. 30k stainless steel plate is suspended from the steam drum by four 1/ h-in,-diem stainless steel wire csbles. The plate clears the tops.of the thimbles by 1/4k-in. so that none of the weight of the steam drum-end astteched beyonets is carried by the drain tenk itself (see Section 6.3.5, following). The 1-1/2-in. nozzles on the-bottom of the steam drums extend sbout 7 in. into the drums. The 1/2-in. downcomer tubes bend inside these nozzles and exit through the nozzle wall. The elevation of these exit openings alternates in adjacent thimbles on both bayonet ¢ircles, one-half being at 1 in, sbove the steam drum lower head and the other half at 5 in. (see ORNL Dwg. D-FF-A-40465). With this errangement, the water level in the drum may be adjusted to-take. ohe-half of the cooling thimbles out of service and thus obtain better control of the temperature of the salt stored in the tank. L The hB-in.-diam by 18-111, -h:lgh steam-drum has an 8-1n. pipe pene- tration through it at the .center (see Fig. 2.6 and ORNL Dwg, D-FF-A-LOWS6). The central openinge allow the 3«in, .inépection nozzle on the drain tank to extend ebove the steam drum.for-eccessibility. ILifting eyes on the top of the steam drum allow the drum and the attached bayonet tubes to be ralsed and set aside for-meintenance. on the drain tenks. The 3-in. steam outlet and the. l/ 2-1n‘;_, water inlet connéction nozzles on the steam drum are fabricated of INOR-8 between the drum and the bolted disconnect couplings. The mating flanges-and-the-remainder of the piping in the heat removal system ere. -3014» stainless- steel. . '.I'he 3-in. steam piping conteins a corrugated, bellow-type, - -stainless steel -expansion .joint in a horizontal run inside the drain. tenk. cell. -The. 1/2-in. water line has sufficient flexi'bility without use of an expansion Joint. The condensers and 'bhe feedwater tanks used in the heat removal systems are described 1n Section 6.3.3., . e : The drain-tank wall temperatuz?e».- is monitored by 20 thermocouples, Two of these are located bn the top .head -, é:b thé fuéi : éjrsfi_em dré-in and £i11 line; four are located on .the bottom head, two of which are at the center; the remaining 1k are distributed over the cylindrical tank wall. Two of the thermocouples on the wall are at the tank charging line. The data logging system is supplied with thermocouple readings from the fuel ~ 4 234 gystem £ill line, the tank charging line, the tank wall near the midplane, ‘ii . and at the center of the bottom. One of the tank wall thermocouples is connected to a temperature recorder and the remaining lead to a scanner which monitors and displays the values. The previously mentioned thermo- couple bayonet assembly, which is inserted into a thimble in the drain tank, carries five palrs of thermocouples distributed over its length, One of the lower of these couples is connected to the data logger and one, Just aebove midplane, has its output read on & temperature indicator. 6.3.2 Design - The drain tanks, thimbles, bayonet cooling tubes, steam drums, and all attachments welded to them, with the exception of the flexible hoses, are febricaeted of INOR-8 and generally in accordance with Specification MBR-62-3.125 The flexible hoses were fabricated of Inconel and meet the specifications of Section VIII of the ASME Unfired Pressure Vessel Code. *T e The drain tenks will withstand an internsl pressure of 65 psig and 1300°F in accordance with.the requirements of Section VIII of the ASME Unfired Pressure Vessel Code, for primary nuclear vessels.so The allowable stress in INOR-8 &t -1300°F was taken to be 3500 psi.16 The calculations for wall and -head thicknesses, etc.,-were based on standard relationships and are presented in Part IV of Ref. 18 and in Ref, 104. > Basic design data are shown in Table 6.1, Calculstions covering.differential thermal expansion between the drain tanks and steam drums,“énd transient and off-design operating con- ditions, are also given in.Pert IV.of Ref. 18, The drain tank and coolinéwsystem.was\designed for a coolling rate of 100 kw. Heat trensfer and hydraulic computations are given in Part IV, Ref. 18, » o { 6.3.3 Decay Heat Removal System The heat generated by the decay of fission products in the fuel salt stored in the drain tenks is removed by boiling water in bayonet tubes inserted in thimbles which are immersed in the salt. This arrange- . ment provides double barrier protection between the salt and the water. Ksj ow A 235 The saturated steam-water mixture from the beyonets is discharged into a steam drum, where the water is separated and recycled to the bayonete. The steam 1s condensed outside.thc.d:ainftank cell and the condensate returned by gravity through flow-control valves to the down- comeré in the basyonet cooling tubes. The relisbility of the system is enhanced by this simplicity of operation. The drain tanks, thinbles-bayonet tubes, and steam drums, all located in the drain tank cell, have been described in Section 6.3.1 The condensers and feedwater tanks are located in the west tunnel, an area which is not asccessible vhen the reactor is in operation but can de entered a chort time after shutdown. The two condensers are commerciel.shell and tube units, about 8-5/8 in., diem by T ft 10-1/2 in, long, with ebout 38 fta of surfece and a capaclty " of 300 kw. Other dimensions end date are givén in Tsble 6.2. The units meet the requirements of the ASME Unfired Pressure Vessel Code, Section VIII, for secondsry nuclear vessels.g9 The chell-side design pressure 1s 50 psig, although the steam will condense in the shell at essentially etmospheric pfésSuré. The .cooling water, or tube-side, design pressure 1s 150 psig. The shell, tubes, and~baffles are all febricated of 304 . steinless steel. The two cylindiical feedwster tenks are 36 in. in diemeter and sbout 24 in. high, including the ASME flanged and dished torispherical heads. Each has a volume of;dboutu10,5wft3. They .ere constructed of 304 stain- less steel, with a wall thickness of 3/16 in., in accordance with the requirements of Section VIII.of the ASME. Unfired Pressure Vessel Code, for secondary nuclear veSseis.#g-«Eadh,tank.is.supported'by four legs, and the bottom of-the,tgnkmisudbou$012 in. sbove floor level. A 1l-in. nozzle at the center of the lower-head serves ss both the condensate inlet and outlet, the tenks "floating" on lines 806 end 807. Both top and bottom heads have 1/2-1n;~nozzle87for\the level indicator connections, the top nozzle elso serving as & ventqur the teank., A 2-in. flanged nozzle is provided at the top of each tank as &an ihspeétion port. As previously mentioned a feedwater control valve in each heat removal system, ICV 806 and ICV 807, control the gravity flow of conden- sate from the condensers and feedwater tanks to the steam drums. These 236 Teble 6.2 Design Date for Condensers in Drain Tank Heat Removel Systems 1. 2. 3. k. 56 6. Construction materiel Shell, tubes, baffleg, and tube sheet Die., of shell Overall length No. of units required Heat transfer rate, cepacity Design pressure Shell side Tube side Test pressure Shell side Tube side , Operating pressure, shell side Design temperature Heat transfer surface No. of tubes Tube size Tube spacing Type 304 SS 8-5/8 in. T £t. 10-1/2 in. 2 300 kw 50 psig 150 psig T5 peig 225 psig 15 psisa 26T F 38 £° 19 "U" sheped 5/8 1n. 0. D. 13/16 in. triangular pitch -4 € o ” " oy s " « 237 pneumatically operated valves were selected to fail in the open position, since overheating the drain tanks is more serious than overcooling, par- ticularly in that the latter could be largely overcome by the electric heaters. By controlling the water level in the drums, the entrance openings at two levels in the bayonet tube downcomers permit the cooling capacity to be off, one-half off, or all in operation, thus affording control of the salt temperature in the drain tanks. The condenser shell spaces and the feedwater tanks are vented to the vapor-condensing system tanks, which are at essentially atmospheric pressure. The entering steam drives the air out. When the steam supply is cut off, air will be drawn in as the remaining steam condenses. All the water in the heat removal systems can be stored in the feed- water tanks. The water in the steam drums can be evaporated, using the drain tank heaters, and collected in the feedwater tanks. Design calculations are given in Part IV of Ref. 18, 6.3.4 Drain Tank Electric Heaters and Insulation The two drain tanks are heated by cylindrical "furnaces" surrounding the tank walls. The tank tops, bottoms, and heater units are enclosed in canned insulation units. The heaters for drain tank FD-1 have a total capacity of L46.9 kw and those for FD-2 a total capacity of 45.0 kw. The difference in heater capacity is due to the arrangement of heaters re- quired for the different nozzle locations on the two tanks. The tank wall heaters are arranged in removable vertical sections, or paneis, each about 2 3/8 in. thick (see ORNL Dwgs E-MM-B-5168L and 51685). The heaters are arranged into two groups, an upper and a lower, each gfoup being supplied with electric'power from a separate induction regulator (see heater schedule,-ORNL.Dwg-E;MM-B-51651). There are two ~widths of panels,'one covering about 35° of the tank circumference, and the other about 15°. On FD-1 there are six of the large penels, with a capacity of 3680 watts (at 230 v) each, and one of the smaller panels (1360 watts at 230 v), in the upper group of heaters. There are a simi- lar number in the lower group. Drain tank FD-2 has five of the larger units and three of the smaller in each of the upper and lower groups. 238 The heaters in each group are connected-in parallel to the wye- connected secondary of the power transformer. Unlike other heaters in the MSRE, one terminal of each of the drain tenk heaters ls grounded through the grounded center tap of the transformer wye. Each of the large panels contasins four heating elements consisting of curved ceramic plates in which the nichrome heating wire is embedded. The elements are mounted in stainless steel frames and enclosed in l6-gage 34T stainless steel to complete the panel assembly. Each panel has & 11ifting hook end seperate power and thermocouple disconnects (see ORNL Dwg. E-MM-B-51610). The outside of the heaters and the tank bottoms are insuleted with two 2-in,.-thick layers of expanded.silica (Careytemp 1l600°F - see Section 5.6.6.3) insulation. The high temperature side of the sheet metal cans for the insulation is febricated of ll-gage 347 stéinless steel. The low temperature, or outside, surface of the cans is 1l6-gage carbon steel. An insulated cover fits between the steam drum and the drain tank at an elevation just below the bayonet. tube .positioning plate. This location permits the primary system drain.end £ill lines to be inside the heated furnace. The 4-1/2-in,-thick cover 1s fabricated more or less in place and is an integral part of the steam drum and bayonet tube assembly. A 6-in,-wide iortion of the cover on the outer circumference consists of two 2-1in.-~thick layers of expanded silicae insulation. The remaining inner portion is insulated with ceramic fibers (Fiberfrax - see Section 5.6.6.3). This flexible type of insulation is. used becasuse it is easier to fit around the large nurber of bayonet cooling tubes. The insulated cover is canned in l6-gage 34T stainless steel on both sides. All of the drain tank heaters are designed for use and none sare connected as spares. The installed cepacity of sbout 45 kw for each tank, however, is greatly in excess of the 20-kw measured heat loss from & drain tank at 1200°F. The same tests indicated that ebout 34 kw is required to heat the tanks from 50 to 1150°F at a rate of 67°F per hour. 6.3.5 Supports for Drain Tenks Each of the two drain tenks ig supported by two columns resting on the drain tank cell floor (see ORNL Dwg. E-FF-D-41500). The supports 126. O -y A t », fiw 239 were designed for a load of,17,00071b.127 Each drain tank installation incorporates two pneumatic weigh cells for estimating the inventory of salt in the tanks. » ‘ Each drain tank is provided with a support skirt welded to the tank Just sbove the upper head- circumferentiel weld. Twelve type 316 stainless steel hanger rods, 3/4 in. OD by .15 in. long, are fastened by clevis- type couplings to this skirt and suspend the tank from'a support ring located at about the elevation of the bottom of the steam drum. This carbon steel support ring is ebout 53 in. OD x 6-1/2 in. wide x 8 in. deep, built up of steel plates, and has two 22-3/k-in.-long arms extending from it on opposite sides. Each of these arms is suspended by three hanger bolts, 1/2-in. OD by 38 in. long,-fabricated of carbon steelf, from a prneumatic weigh cell resting on. top of & support column. Each of these two weigh cells has a point support consisting of a bearing ball 3/t in. in diameter. The support columns are febricated of 5-in. sched-LO carbon steel pipe, except for the topv25min., vhich is k-in, sched-4O pipe, and rest on the drain tank cell floor. The columns pass through holes in the arms on the support ring with 1/k-in.. clearsnce on a diameter, an amount sufficient to allow proper-operation.of the weigh cells while at the same time to prevent the tank assenmbly from falling off the two support points. The long hanger bolts and the point. support arrangement reduces the horizontel leading on the weigh cells to a negligible amount. The steam drum end bayonet assembly also rests on the support ring mentioned sbove and is thus a part of the total loading indicated by the weigh cells, o To effect meintenance on & weigh cell or prior to removal of a drain tank ofrits'cobling system, the weight‘of the drain tank assembly must be removed from the weigh cells. To accomplish this, the end of each ‘support ring arm 1e equipped with a jack bolt which operates against a bracket on the supporting columns jJust below the axrm. A slight 1lifting of the arm by this bolt will permit unthreading of the three hanger bolts on each weigh cell. It may be desirsble to remove the weight from the *¥*ASTM A-193 Grade BT. 240 Jack bolts for example to prevent swaying during removal or replacement | . of the steam drum and beayonet assembly. To provide for this a collar is installed on each column just below the arm onto which the weight of the assernbly cen be lowered by backing off the jJack bolts, On initial installation, the bayonet tubes were lined up and guided into the thimble openings under shop conditions. Replacement of the steam drum - bayonet tube assembly in the radioactive drain tank cell environment requires use of a guide plate slipped over the lower end of the beyonets to align them for-entry into the thinble openings. The i thimbles have flared openings to assist in this operation. Once inserted, - the steam drum assenbly is lowered, with the guide plate slipping up the R bayonets, and the plate is left in place resting on the tops of the thimbles. Further description of maintenance procedures is given in a Part X. 6.4 Fuel Flush Tank | The flush-salt storage tenk is located in the drain tank cell, Fig. 4.4 and Fig. 4.5, and is used to store the salt used to cleanse the primary system prior to charging with fuel salt. The flush salt consists primarily of 66% 11'F end 34% Bth (see. Table 2.1 and Part IV). The flush-salt tank has the same dimensions a&s the fuel drain tanks (see Section 6.3, ebove) but is two inches shorter in overall height, The tank has a storsge capacity of 82.2 f‘t3, however, as compared to 80.2 ft3 in the drain tanks because of the absence of cooling thimbles. The materlals e of construction and the design criteria are the same as for }‘the drain tenks. The design data are summarized in Tsable 6.3. The design calcu- lations are presented in Part IV of Ref. 18. The flush salt tank 1s supported in the same manner as the drain tanks and is heated by an identical electric furnace arrangement having a capacity of 8.8 kw. The thermal insulation is arranged in essentially the same fashion. The tank temperature is monitored by 15 thermocouples. Two are on the top head and four are on the bottom head with two of the letter et the center., The other nine thermocouples are distributed over the tank wall surfaces, with two of these at the charging line. -~ The l-in, drain line 104 encircles the flush tank, FFT, at the top | “ " aw 241 Cooling methgd T Teble 6.3 Design Date for Fuel System Flush Salt Tank Construction material INOR-8 Height, in. ~8l Diameter, in. (0.D.) 50 Well thickness; in." | Vessel 1/2 < Dished head 3/4 - Volume, £t ( 1250°F) g . Total o C ~82,2 Flush salt (normal £ill conditions) 73.2 Gas blanket~(normasl £ill conditions) 9.0" ’ Design temperature, °F - 1300 Design pressure, psi 65 | None 242 to provide the flexibility needed for weigh cell operation, in en arrange- ment identical to that on the drain tenks., This line has a freeze valve, FV-th', and the salt transfer line to the fuel-processing eeli_ &lso has & freeze valve, FV-10T (see flowsheets, Fig. 6.1--ORNL Dwg. D-AA-Ak0882, and Fig. 6.2--0RNL-Dwg. D-AA-A-40887). The flush sgalt tank is vented to the fuel salt circulating pump bowl, via lines 576 and 546, and to the off-ges system, through lines 576 and 57T, each of which has pneumatically operated control valves actuated by hand-operated regulators located on the control panels. The two-point level :I.ndicat_ion system 1s identical to that used on the fuel drain tanks. | 6.5 Salt-Transfer Pipe Line Supports Drein line 103-is supported by nine constent-load Bergen supports, as shown in Table 6.4k. Three of these supports are located in the reactor cell and eix are in the drain tank cell. Pipe hangers (both mumbered S-5) support each end of a heem. passing through the opening between the reactor and drain tank cells to support that portion of line 103. Line 103 is anchored at the heating lug connection near the junction with line 104 in the drein tank cell. ) Line 104, 105, 106, and-110 each have one constant-load type pipe support. The 1/2-in. piping, lines 107, 108, and 109 are mounted in simple fixed pipe hangers; € » Teble 6.4 Salt Transfer Pipe Line Supports® MSRE Line Bergen Numbefb Preset Load® Maximum Hanger Maximum Calculated Support Numbexr Location and Type Tbs Movement, in. Pipe Movement.on Nunber Heating, in. S-3 103 About 1 ft outside CSH-1 D-1 100 1 - 1-1/8 thermal shield S-4 103 Between S~3 and S5-5 CSH-1 D=1 100 + 1 S-5e 103 About 5 ft from reactor CSH-L4 D-1 235 + 1 -1/2 cell wall 8-5° 103 About 6 in. from south CSH-I4 D-1 235 + 1 -1/2 wall drain tank cell S-6 103 Middle of south wall of CSH-1 D-1 119 1 -3/8 drain tank cell S-T 103 Southwest corner of CSH-1 D-1 121 + 1 -1/k drain tank cell N -8 103 Middle of west vall of CSH-1 D-1 127 £ 1 5/32 o drain tank cell §-9 103 At 90° bend on west wall CSH-1 D-1 115 + 1 -1/16 of drain tank celil 8-10 103 About T £t from west wall CSH-1 D-1 121 1 negl, of drain tank cell Anchor 103 About 3 £t 4 in., from - - - - east wall drain tank cell S-11 104 South of FV-10k CSH-5 D-1 365 + 1 -1/k S-12 106 North of FV-106 CSH-k D-1 2ko + 1 -1/k S-13 105 South of FV-105 CSH-4+ D-1 260 + 1 -1/4 TL 110 Near north wall of CSH-1 D-1 100 1 -1/2 drain tank cell See ORNL Dwg d Positive values are up; negative values dowm. a b Constant-load type supports Corporation (New York, N.Y. 5 Bergen Pipe Support ¢ Preset load is expected welight of pipe and contents. e S-5 hangers support each end of a beam which supports line 103 hetween reactor and drain tank cells. b T. SAMPLER-ENRICHER SYSTEM The MSRE includes provisions for dipping 10-g samples of salt ffom'both the fuel and coolant-salt pump bowls while the reactor is in operation. ©Shielded carriers are provided for transporting the samples to the analytical laboratory. Chemical analyses of the samples provide frequent observations of the behavior of the salts and, in the case of the fuel salt, of the uranium inventory in the system. The sample-~taking system may also be used during reactor operation to add up to 150 g of enriching salt (72 mole % LiF - 28 mole % UFh) per sample capsule, to compensate for the burnup of fissile material. ©Should 1 it become necessary, the same system may also be used to add a nuclear poison (IiéF-BeFé) to the fuel-salt circulating loop. (To make gross changes in the fuel-salt composition, it is necessary that it all be drained from the circulating system and transferred to the fuel-sglt processing cell.) The sampler-enricher systems for the fuel-salt and coolant salt systems operate on the same principle. The primary differences between the two stem from the fact that the radiocactivity level in the coolant salt is much less than in the fuel salt, that the containment of fission- product gases is not a problem, and that the equipment can be approached a short time after reactor shutdown for adjustment and maintenance. The * fuel-system sampler-enricher is described in Sections 7.1l through 7.9. The equipment for the coolant-salt system is briefly covered in Section T.10. T.1 Brief Description of Operation The sampler-enricher system consists of a 1-1/2-in,-diam transfer tube connecting the top of the pump bowl to a two-chambered, shielded transfer box on the operating floor level. A small copper capsule, fastened to the small wire cable by a special latch, is lowered through the tube into a cage beneath the surface of the salt in the fuel-pump bowl. The capsule, with its lb-cc sample (10 g of salt), is then pulled up through the tube, through two gate valves, and into the shielded Q;; P e 4n * 245 leaktight trensfer box. Using e simple manipulstor and a periscope, the sample capsule is unlatched from the ceble and transferred to a trensport conteiner gbout 1-3/8-in. in diemetertty 18-in. long. After the trensfer box has been purged, e.removal tool is inserted and the transport container is pulled up into e lead-shielded transport cask. This cask is then placed in & sealed container and teken to the ana- lytical chemistry facilities in the X~-10 Area of ORNL. Two or more berriers are provided at all times to guard ageinst escape of radiosctive gases or particulates. Eight inches of lead, or equivalent, shield the operator from radicactivity. A system of inter- locks in the sampler-enricher system prevents asccidental opening of valves, etc. A procedure in reverse of that described ebove is used for adding enriched salt to the system. A longer copper cepsule is used, holding 50 cc. This cepsule is lowered into the pump bowl where the enriched materiel quickly melts and drains through openings in the capsule as it 1s raised from the bowl, Poison material may be edded in essentielly the same manner, 7.2 Design Criterie The unique features of the sampler-enricher system--primarily the faect that the sample-transfer tube passes through both the primary and secondary containment barriers in the MSRE~-~-led to adoption of relatively stringent criteria for the design of the system.128 In summary these are* ' : 721 s_agp__g. The samples teken must be representative of the salt circuleting in | the.system, Tt may 8lso be desirable at times to teke separate semples in vhich the material floating on the surface of the salt in the pump | bofilibfedominatee. 'Each sample mist be easily removeble from the cep- ' sule, end 81l of it recovered for chemical enalysis. Approximately L cc (10 g) of salt must be isolated per sample, and the system must be capable of taking three samples per 24 hr for one year or more. During prenuclear runs, etc., the sampling may be more often. » 246 7.2.2 Enriching o About 30 cc (150 g) of enriching selt (72 mole % 'Lis - 28 mole g UF%;;i]; be ._e,d'ded per cepsule. Each 30-cc esddition will.-contain 90 g of U and./or thorium. The capsule mist drain completely, and re~ covery of the empty capsule must be assured. The enriching salt xmist enter the circulating fuel stream as & liquid, not as a solid. | | T.2.5 FPoisoning The system must be capeble of adding a nuclear poison to the fuel- salt-pump bowl at all times, including outages of the electrical power supply. o T.2.k Addition of Conteminents Belium gas introduced into the salt loops during sempling or en- riching operations must be of reactor grade. Portions of the system in contact with the salt must be febricated of INOR-8 or other materials that will not edd conteminants to the system. A dry inert gtmosphere mst be maintained around the sample at all times, ineluding transport to the snalytical lsboratory. (The capsule may be fired in a hydrogen atmosphere prior to use to remove the oxide film.) T.2.5 Containment Fission-product gases entering the sampling compartment mst be purged to the off-ges system prior to removal of & sample. The sample mist be sealed in e shielded container during transport, Por‘bions' of 3 the sempler system which could be contamineted by particles of salt mst be sesled from exposure to the atmosphere. Double conteinment mst be provided in such & manner that breasching of one barrier will not result in the release of radioactivity to the environment. All mechanicel seals and valves in the primary areas must be buffered with helium gas to a pressure higher than that in the reactor system, and leak-detection equipment must be provided. Any portion of the system not structurally strong, such as the flexible bellows, imxst — be buffered with gas under a pressure less than that in the primary | b & ) Ay i e 247 system, and the buffered space must be vented to the containment air system. Exhaust hoods must be provided in the operating floor areas where the sampler-enricher equipment is located. (For convenience, the containment areas in the sampler-enricher system were classified as follows: Portions of the primary contain- ment were designated l-a, 1-b, etc. Areas of secondary containment, such as the interior parts of the valve box, were designated 2-a, 2-Db, etec. The outer compartment of the transfer box, also a secondary con- tainment area during certain phases of the operating procedure, is designated 3-a, etc. See Fig. 7.3.) All portions of the primary and secondary contginment areas must be helium leak checked and the leak rate must be less than 1 x 10"8 std cc/sec. T.2.6 Stresses The sampler-enricher equipment must be designed for a pressure of at least 50 psig in primary containment areas and 40 psig in secondary containment regions. Design temperatures range from 12000F in the pump bowl to about 100°F at the transfer box. (The normal operating pressure is about 5 psig.) The calculated stresses in stainless steel must not exceed those allowed in the ASME Unfired Pressure Vessel Code, Section VIII,h7 and those in INOR-8 must conform to the allowable stresses shown in Table 2.2 and ASME Boiler and Pressure Vessel Code Case 1315. The primary containment must comply with ASME Code Case 1273 N-7°° and secondary confainment with Code Case 1272 N-S.ug 52 T.3 Description of Equipment 7.3.1 Capsules Two types of copper capsfilés.are used, one for sampling and one for adding enriched or poison material. " T.3.1,1 Sampling Capsule. As shown in Fig. 7.1, the sampling capsule is fabricated from a 3/L-in.-OD copper rod, drilled to 5/8-in. ID, with a rounded bottom. The solid copper top cap is also rounded to minimize the likelihood of becoming stuck in the transfer tube or 7.1. Sampling (Left) and Enriching (Right) Capsules. Unclgssified Photo 71333 8%c 42 249 velves. The cap is pinned to the capsule with & short length of l/8-1n. OD copper tubing. Two holes through the cap permit the 1/32-in,-OD twisted Tnconel wire latch csble to pass in end out to provide & T-in.- long loop connecting the capsule to the latchkey, to be described below. The overall length of the capsule, with end cap, is ebout 1-13/16 in, Holes, 180° apart, in the side of the capsule, sbout 0.88 in. sbove the bottom, end roughly elliptical in shape, 1/k by 3/8 in., with the major axis et right gngles to the axis of the capsule, permit the salt to enter the sampler after immersion in the salt in the bowl. The capsule volume below the level of the holes is gbout 4 cc. A new capsule must be used for each sample. 7.3.1.2 Enriching cap‘éfile. This capsule is also shown in Fig. T.l. It is febricated of 5/h-in.-0D by 0.035-in.-wall-thickness copper tubing. The bottom is spun shut on & redius of 5/8 in. The top is closed with a solid copper plug similar to that used on the sampling cspsule but with two 1/8-in.-OD copper tubes passing longitudinally through it. The molten enriched materiel (or.poison) is add.ed. to the capsule through one of these tubes, which extends sbout 1/k in. on the inside, end the dis- pleced inert gas is vented ‘through the other. After £illing, the 1/8-in,- OD tubes are cut off short &nd sealed. A hole is drilled through the cap at & right angle to the centerline for the 1/32'-'-111.-0D Inconel wires used to attach the latchkey. Nine 0.191-in.-dism holes are then drilled in the side of the capsule 1200 epart and et 1-1/k in., 2-1/2 in., and at 3-3/k in, from the bottom. A tenth hole, 0.221 in. in diemeter, is drilled in the bottom. The overa.ll length of “the. salt-addition tube is gbout 6-3/8 in, end it holds epproximately 30 cc, or sbout 150 g of salt (90 g 235‘8) On insertion into the pump bowl the salt melts and drains from the capsule. as it 1s lifted. out. A _z;ew.capsule is required for each salt addition. - Te 5.2 Cepsule Iatch and Le.tchkey A lsteh is provid.ed a.t the end of t.he csble which ra.ises and lowers the capsule t0 permit easy enga.gement and disengagement of the cgpsule from the cable. This latch does not come into contact with the salt. 250 7.3.2.1 latchkey. The 1/32-in.-diam Inconel wire attached to the top of each capsule, see above, is fitted with a brass (or bronze) letchkey ebout 3/16 in. OD by 1-5/8 in. long, overall. The key has an enlerged section at the upper end, 5/16 in. OD by about 3/8 in. long, to form & shoulder on the key which engages a notch in the latch, as shown in Fig. T7.2. The key is disengaged from the notch by grasping the latch wire with the remote manipulator fingers and lifting it - slightly es it is pulled forward and upwards. A new latchkey is re- quired for each sample taken. T+3.2.2 Latch. As shown in Fig. T.2, the stainless steel latch » et the end of the cable is 1-3/8 in. diam by sbout 2-1/2 in. long, and is tepered at the lower end to help guide it through the velves in the transfer tube, etc. A slot is provided in the tapered end for in- sertion and support of the latchkey, the shoulder on the key resting on the edges of the slot. The upper end of the latch is beveled to 35°, When the latch is in the full raised position, this beveled surface bears against a corresponding surface on the upper lstch stop in the capsule removal chamber, causing the latch to rotate on the ceble to the desired position with the slot opening facing the access port. The upper latch stop is described subsequently in Section 7.3.7.1. ] 0, & T+3.3 Csble The ceble used to lower and raise the cepsules through the trans- fer tube is a Teleflex, Inc. (North Wales, Pa.), Catalog No. 19553, 0.118-in.-dism by 25-ft-long 321 stainless steel cable. It is coated with e high-temperature lubricent supplied by Teleflex, Inc., The cable can operate under a 35-1b tension load without belng damaged. [ 4 T.3.4 Pump Bowl Equipment T.3.4.1 Capsule Guide Cage. A guide cege is provided inside the pump bowl to confine the capsule to its proper position in the pool of salt. As shown on ORNL drawing F-RD-9846-G, the cage is fabricated from five 1/4-in,-diem by 8-1/4-in.-long INOR-8 rods attached to a g) 1-1/8-in,~diem ring at the bottom. s L1 LA ] -\ 2-11/16 REF - CORE CAPSULE KEY/- Fig. 7.2. Sampling Capsule Cable Latch. Unclassified ORNL DWG 64-8822 CABLE COUPLING — SPRING POSITIONER LATCH STEM SLOT - 252 7.3.4.2 Iower Latch Stop. A stop is provided in the connection between the transfer tube and the capsule guide cage to prevent the < latch from entering the cage and coming into contact with the salt. The stop consists of a restriction tapering from 1-5/8 in. ID at the top to 1-1/16 in. ID at the bottom. The latch stop also serves to support the top ends of the rods for the guide cage. T.3.4.3 Baffle. A baffle plate surrounds the capsule guide cage to shield it from excessive salt velocities and, more importantly, to retard the aerosol of salt in the vapor space in the pump bowl from 4 entering the transfer tube. This baffle is & spiral-shaped INOR-8 plate, 1/8 in. thick by 8 in. high, curved to about 3 in. overall digmeter. " T.3.5 Transfer Tube A 1-1/2-in. sched-h0 pipe connects the top of the fuel pump bowl to the bottom of the maintenance valve in the sampler-enricher valve box located st the operating floor level (852-ft elev). (See Fig. 4.3.) The pipe, or transfer tube, is about 1l ft long, with two 35-1/20 by 15-in. radius bends at the top and botiom, with the central straight portion inclined at an angle of 54°30' with the horizontal. This is sufficient slope for the capsule to drop into the pump bowl by gravity alone (see Fig. 7.3). The transfer tube is fabricated of INOR-8 from the pump bowl to the expansion joint section, described below. The expansion joint and . the upper portions of the transfer tube are 304 stainless steel. 7.3.5.1 Expansion Joint. The transfer tube includes an expansion joint at about the mid point to provide the flexibility needed to ab~ sorb the movement of the pump bowl (see Section 5.4.5) relative to the fixed sampler-enricher station. The expansion joint section, or spool piece, is about 40-1/2 in. long (see ORNL drawing D-BB-C-U41337). The upper portion of the spool piece is a sliding fit into the lower portion, with a clearance of 0.003 to 0.007 in. Points of contact have ground No. 6 Stellite surfaces. A 321 stainless steel bellows, 3.3l in. OD x 2.65 in. ID x 7 in. long, with a 2-ply wall, each 0.005 in. thick, and g;; with 32 convolutions, is welded to the upper and lower portions of the L 4n &y 253 Unclggsified ORNL DWG 63-5848 % REMOVAL VALVE AND SHAFT SEAL PERISCOPE LIGHT N / CAPSULE DRIVE UNIT — LATCH-_| ACCESS PORT— CASTLE JOINT (SHIELDED ~ WITH DEPLETED URANIUM) AREA 4C (PRIMARY CONTAINMENT) — é:‘ ’ SAMPLE CAPSULE — ] B MANIPULATOR AREA 3A (SECONDARY CONTAINMENT) i _[ / ‘_ SAMé’(I)_-ETTRflél\éSPORT IR NTAIN LEAD SHIELDING o OPERATIONAL AND MAINTENANCE VALVES SPRING CLAMP DISCONNECT \ N—I-E % TRANSFER TUBE (PRIMARY CONTAINMENT )~y AREA 2B (SECONDARY CONTAINMENT) LATCH STOP — MIST SHIELD ! 0 ! 2 \-CAPSULE GLIDE FEET ” Figure 7.3. Schematic Represénta:bion Fuel-Sslt Sempler-Enricher Dry Box 254 spool piece to provide a leaktight joint. The bellows was manufactured by the Fairchild Instrument and Camera Company (El Cajon, Calif.). A permanently attached jack, operated by a system of bevel gears and roller chains motivated by a remotely operated tool from above, permits compression of the expansion joint for insertion between the flanges at the connection at each end. (See ORNL drawing D-BB-C-41365.) A po- sitioning jig for the spool piece provides proper alignment of the flanges during reinstallation. The flanges for the spool piece are, as are the other flanges in the transfer tube assembly, 4-1/L in. OD, integral O-ring, leak-detected units, with the mating faces held together by spring clamps which can be remotely removed by special tooling operated through the portable shield. Te3.5.2 Sleeve. The upper portion of the transfer tube passes through a sleeve as it crosses the annular space between the inner and outer reactor containment vessel walls. This 6-in. sched-4O pipe is about 5-1/2 ft long, overall, and is provided with a bellows-type ex- Pansion joint at the mid point to compensate for relative movement be- tween the walls of the two vessels (see ORNL drawing D-KK-D-409Th). Iead shielding fills the annular space between the sleeve and the trans- fer tube for a distance of 20 in. T+3.5.3 Upper Terminus. The upper end of the transfer tube passes through a box set into the concrete gt the operating floor level. The box, fabricated of a 5-in., section of ll-in. sched-10 pipe, is closed at the top by a 21-in,.,-diam by l-l/2-in.-thick flange bholted to a cor- responding flange on the top of the box with a double O-ring gasket, which can be leak detected. The transfer tube is welded to, and extends through, the flange. The 1-1/2-in. pipe terminates inside the valve box, described below, about 7-5/8 in. above the operating floor elevation of 852 ft in a 4-1/4-in.-0D integral O-ring flange having a spring-clamp closure. T.3.6 Operational and Maintenance Valve Box Two mechanically similar gate valves are located one above the other in a sealed valve box at the upper end of the transfer tube assembly. The upper--or operational-~valve is used during normal operation of the s » 4} -5 255 sampler-enricher systém__.»-. The lower-~-or maintenance~-velve is normally open and is closed only during maintenance on the upper portion of the sampler-enrichei‘ equipment, or in case of failure of the opergtional valve to seal prope:_:‘l&. | | 7.3.6.1 Valve Box. The valves are located in & box sbout 15 in, x 19 in. x 38 in. high. The 15-in. by 38-in. sides face north and south, and the 19-in., by 38-in, sides face east and west. The southern side of the box has a cover plate bolted to the box by 1/2-in. studs on ebout L-in. centers, and a neoprene .O-ri_ng gasket with metal-to-metal seats. The upper portion of this cover has en opening, which, in turn, is closed by another cover plate with a neoprene O-ring gasket and bolted down by the same 1/2-in. studs, the studs being longer at the top of the box to accommodate the two thicknesses of cover plates. The valve body is welded to the transfer tube and therefore the major portion of the weight of the valves and flanges is carried by the flange welded to the trensfer tube at the operating floor level. The valve operating stems pase through the box cover plate in bellows-sealed Joints. These joints segl the opening and also allow some lateral movement of the velve for alignment, The two seals, or Joints, are welded to the box cover plates, the lower one to the large Plate and the upper one to the smaller , outside cover plate. Vertical alignment of the valves and flenges is achieved by slotted holes in the cover plates, permitting vertical shifting of each cover plate (ebout 1/4 in,) relative to the flanges end to each other. Six 1-5/8-in.-d.iam ta.pped holes are provided in the 19 by 38-in. west face of the box, each 0pposite an operator for the spring clemps on the three velve flenges. The holes are normally closed stainless steel nuts, sbout 6 in. long, which extend through the lead shielding on the outside of the box. The nuts are provided with neoprene O-ring gaske‘bs. - . : - : ' o | ~ The valve box 1s febricated of 304 stainless steel. Two stiffeners “of 1/2-_1n.-thick by 3-in.-wide plate are equally spaced verticelly on the three sides of the box. The box was designed for a pressure of 40 psig at 100°F, although the normsl operating pressure is atmospheric. The box was hydraulically tested to 54 psig or pneumatically tested at 256 46 psig. It satisfactorily pessed a helium lesk check, with & maximm leakage of 1 x 1070 sta cc/sec (see Section 7.2.6). o « 7.3.6.2 Valves. The operational end maintenance velves are | 1-1/2-in., 150-1b stainless steel body, "Belloseal" gate valves manu- factured by The William Powell Company (Cincinnati). The valves are the double-sealing type, with No. 6 Stellite-to-Stellite metal seats. A helium pressure of 4O psig is maintained between the two sests when the valve is closed. The normal lesk rate through both seats is less than 1 std cc of helium per minute. The valve stems were modified by < cutting and inserting sbout 6 in. of extra length so that a second stainless steel bellows could be added to the stem seals. The valves are operated by "Limitorqpe," SMA-000, control motors located outside the valve box. The motors are for 220-v, 3-phase oper- ation and have an output torque of 2 ft-1b, which is geared to produce 50 £t-1b at & stem speed of 6 in./min. -On closing, the torque-limiting feature cuts off the drive when the valve is fully sested. The inter- locks in the sampler-enricher electrical system prevent operation of either valve motor while the cepsule is in the transfer tube. The motors draw power from the 25-kv motor-generator set which can be supplied with auxiliary battery power in event of failure of the normal supply. In addition, the valve stem drive can be shifted to manual operation for (w emergency closing of the valves. T.3.T Transfer Box . As g sample capsule is withdrawn through the transfer tube, it passes upward through the maintenance and operation valves in the valve box and then into é cgpsule asccess chamber located in the transfer box. As shown in Figs. 7.3 and 7.4, this box is located Just gbove the valve compartment. In addition to the access chamber, in which the sample capsule is disengaged from the lifting cable, the transfer box also contgins the cable drive box, the menipuletor, and the valve port for introducing the capsule transport container. The interior of the trans- fer box, sometimes referred to as the outer compartment, is & region of secondery conteinment when the operational and maintenance valves are ‘saj 257 » Capsule Access Chamber. 4 7 Fig 258 open. The capsule access chamber, or inner compartment (area l-c in Fig. 7.3), is a primary conteinment region at this time. Te3.T.1 Capsule Access Chamber. the transfer tube assembly is welded to the bottom of a bellows, which, in turn, has the top welded to the bottom of the capsule access chamber (see Fig. T.4). minor misalignment. each wall 0.00L4 in. thick. long, has eight convolutions, and was tested at 75 psig. facturer was Fairchild Instrument and Camera Company (El Cajon, Calif.). The bellows described above is housed in a guide gbout 5 in. diam by 5-3/h in. long, welded to the bottom of the capsule access chamber. The outside of the guide is provided with two neoprene O-ring gaskets and fits into a short cylinder in the top of the valve box. flanged joint above the operational valve is separated, this arrange- ment permits the capsule access chamber and cable drive unit to be with- drawn for maintenance through the top of the transfer box, as will be described subsequently. The 304 stainless steel capsule access chamber has a square cross section, about 4-1/2 in. on outside dimensions, is about 10-3/8-in. high, and has walls about 1/2-in. thick. and a door are provided on the south face. vhich are spring loaded to hold the door in the open position. in Fig. 7.4, the door is closed and clamped shut by three pneumatic cylin- ders on each side, operated by 75 psig helium, which are connected through pinned linkages in a toggle action to lock the door shut after the gas The door is opened by applying helium These same links swing the pressure has been released. pressure to the reverse side of the piston. The 1-1/2-in.~-diam upper end of This arrangement accommodates relative movement and The bellows is 2-ply 304 stainless steel, with It is 2.406 in, OD x 1.562 in, ID x 3 in. The manu- A 2-3/h-in, by 8-in.-high opening The door swings on hinges clamps out of the way when released to allow the door to swing open. The clamps are not attached to the door but have Stellited rounded noses wvhich bear against Stellite pads on the door. can exert a force of 300 1b on the door, are Knu-Vise Clamps, Catalog The clamps, each of which Number AODT-200, manufactured by the Lapeer Manufacturing Company (Detroit). space between the gaskets is buffered with helium when the door is closed. Two Buna-N gaskets are provided on the door opening, and the When the As shown & b 'y i 259 A three-way valve in the helium supply to the pneumatic cylinders vents the spent helium to the conteinment ventilation system. When the cgpsule is hoisted to the fully raised position, the beveled surface of the upper portion of the capsule latch contacts a similarly beveled surface on & stop mounted in the top of the capsule access chamber. As mentioned in Section T7.3.2.2, and shown in Fig. 7.2, this arrangement causes the latch to rotate on the ceble so that the notch faces the door opening. T+3.7.2 Capsule Drive Unit and Box. The electric-motor-driven reel which reises &nd lowers the capsule casble is located in & drive . unit box just gbove the capsule sccess chamber. The interior of the box communicates with the chamber and is thus also part of the primary conteinment. The box is sbout 8-3/6 in. x 14-1/8 in. x 11 in. high and is fabri- cated of 1/2-in.-thick 30k stainless steel plate (see ORNL drawing 10301 R-157-E). The box has a 1-1/2-in.-diam hole at the bottom through vhich the cable passes into the capsule access chamber, The box is designed for, and tested at, the seme pressures as the access chamber. The transfer box has an O-ring-gasketed cover bolted in place just ebove the drive unit box., After the flenge sbove the operational valve is separated, the lifting eyeé'in the top of the transfer box may be used to pull the drive unit box and the attached capsule access chamber as- sembly upwards through the'opening_for maintenance or replacement. . The capsnle'cdbie'drifie unit is a Teleflex, Inc. (North Wales, Pa.), Catalog No. 19553, drive with e storage reel holding 25 £t of csble. The cable is positively paid out end returned by & non-slip geer-driven wheel capable of‘éxefting735'1b'o£'force on the csble in tension and 20 1b in compression. (It is to béinoted,fhbfiever,'that the normal loading 1s but a emall fraction of these values and that the capsule Arops downward to the pump bow1'sole1y:by gravity.) As the cable moves upvard through the arive wheel, it winds onto a storage reel which is rspring-loaded to maintain & tension on the cable between the reel snd the drive wheel, The drive unit motor is a 115-v, single-phase, reversible, Jordan (Milwaukee) "Shaftrol” unit, Model SM-1l-W-3, 1/2 FIS, exerting 28 in.-l1b "~ 3 260 torque at 3-1/2 rpm output speed. It is provided with a built-in electric brake. One revolution of fhe motor reels in about 8 in. of cable. & A thresded shaft, gear-driven from the motor, moves a nut along it to contact limit switch arms. An upper limit, lower limit, end two inter- mediate points are provided. The upper and lower 1ifiit switches cut off the ceble drive motor while the intermediate positions are part of the interlock system. Two gear-driven synchro motors are incorporated into the drive unit to send signals to the "coarse" and "fine" position indi- cators on the operating panel. These show the capsule position to within < 1/8 in. of the actual point, T.3.7.5 Transfer Box Layout and Construction. The box that houses the capsule access chamber and the drive unit is a sealed lL-shaped con- tainer, with the vertical leg sbout 15 in. by 20 in. and 2k in, high, and the horizontal leg about 15 x 15 x 36 in. long (see Fig. T7.3). It is fabricated of 1/2-in.-thick 304 stainless steel plate. Reinforcing bars 1/2 in,-thick by 3-in.-wide are welded along the center lines on the 24-in,.-long sides. The design pressure is 40 psig at 100°F, the normal operaling pressure being atmospheric. The box was hydraulically tested at 54 psig or pneumatically at 46 psig. The helium lesk rate was less than 1 x 10'8 std cc/sec (see ORNL drawing 10301-R-150-E). The box, as secondary contaeinment, complies with the ASME Code Case 1272 N-5. The capsule access chamber is located in the north end of the box, in the vertical leg, with the drive unit mounted gbove it. The south end of the horizontal leg is fitted with a manipulstor and e quartz . viewing port. The upper portion of the horizontsl leg is provided with k9 another quartz port for the illumination system and with a valve port for insertion and removal of the sample-capsule-transport container. These devices ere described separstely in the sections that follow. T.3.7.4 Manipulator. A shielded manipulator extends through the wall of the transfer box. It is used to remove the capsule latchkey from the leatch and to 1lift the sample capsule from the access chamber to the capsule-transport contsiner, etc. As indicated in Fig. 7.3, the manipuletor hand has two fingers of the forceps type. These are asctuated by a push-pull rod extending through the arm to the handle, located out- \_J side the transfer box. A grip-type lever, which has a ratchet and pin, h T 261 or trigger, arrengement to lock it in any position, imparts the push- pull motion to the rod. The hand cen be rotated about 180° by turning - the arm. The insides of the fingers are padded with neoprene about .1/32 in. thick. The erm passes through the box wall in & Castle-type joint. The gide-to-side motion of the arm is provided by a vertically mounted 6—in.-diam'by 8-in.-high depleted uranium cylinder that is mounted on ball bearings at the top and bottom. This cylinder turns, with a clearance of sbout 1/64 in., in & depleted uranium housing fitted into the 1lh-in.-diam extension of the trensfer box. The up-snd-down motion of the hand is provided by a ball-bearing-mounted horizontal axle on &a 7-in.-diem by 1-1/4-in,-thick depleted uranium disk, which turns with ebout 1/64-in. clearance in a cutout in the ebove-mentioned cylinder. Thie gimbel arrangement allows full freedom of swinging motion of the arm to eny position within a cone of sbout 40° included sngle. The ef- fective shielding thickness of the depleted uranfum is 5 to 6 in. All ursnium pleces have hard chrome plating sbout 0,001 in. in thickness, The arm is sealed by & 2-ply-polyurethane, conical-sheped, corru- gated bellows, sbout 8 in. in diameter at the large end and tapering to gbout 1 in. in dismeter to the point where it is clamped at the "wrist" of the earm. Each ply is sbout 0.020 in. thick. The space between the inner and outer bellows 1s maintained below etmospheric pressure. Ef- fluent gas from the space passes to the containment ventllation system, where it is monitored for redioectivity. A cover can, or cap, is placed over the portion of the msnipulstor hendle extending outside the transfer box when the manipulstor is not in use, or if gas leekage is detected in the assembly. This stainless steel can is about 10 in. in diameter by 12 in, long end is joined to the mani- pulstor housing by "Conoseal”™ miltiple T-bolt latches (Catalog No. SOT65H) and uses & tdbe-type_gesket (Catalog No. 50887-10008). 'This can passes the seme lesk ‘checks as does the transfer box. The can also cen be used to eqpalize the pressure on the polyurethane bellows when the transfer box is under pressure or vacuum. T.3.7.5 Viewing Ports and Periscope. A lh-in.-dism viewing port is located on the front of the transfer box. The 1/2-in.-thick quartz lenms 262 is mounted in a pressure-tight, screwed fitting. A simple periscope, using two front-surface mirrors about 2-1/2 by 3 in. and lbcated about 3 £t apart in & 3-in.-square stainless steel box, is arranged at a con- venient height for an operator in the standing position. A knob at the top has a belt drive to adjust the viewing angle of the lower mirror, and the periscope can be rotated slightly to view the required portions of the box interior. The viewing port and the lower section of the periscope are inside the lead shielding which surrounds the transfer box. A hood prevents the operator from placing his face closer than about 7 in., from the upper mirror. A second quartz lens port, identical to the one described above, is located at the top of the transfer box in such a position that the 100-watt electric bulb placed outside the box illuminates the work srea. 7.3.7.6 Capsule Removal Valve. A 2-in. ball valve is located on the top of the transfer box for the removal and insertion of the semple- transport container. The seal assembly for the tube is described below. The valve is a Jamesbury Corporation (Worchester, Mass.) type DHV-33TT, with an air-actuated pneumstic cylinder operator No. O4 Model P-100. A h-way solenoid-operated valve controls the air flow to the cylinder and vents the air to the atmosphere. The valve is enclosed by the lead shielding asround the transfer box. T.3.7T.7T Capsule Removal Tube Assembly. The cepsule transport con- tainer is inserted into the removel valve through a seal assembly de- signed to prevent entry of air into the transfer box. The seal assembly also prevents the escgpe of contamingted gases from the box as the con- teiner is withdrawn. The segl is contained in a vertical stainless steel tube, 2.375-in.~ OD by 11-3/16 in. long, joined with 2-in. 11-1/2 NPT to the removal valve outlet. The upper portion is fitted.with a nylon bushing 3 in., long and with two guiding surfaces, 1.373 in. ID by 3/b4 in. long, at each end, through which the 1.367-in.-0D transport carrier tube slides. Immedi- ately beneath the guide bushing are two Parker No. 220 neoprene O-ring gaskets, 1—3/8.XJ,5/8:x1/8 in., mounted 1 in, apart. The space between the gaskets is drilled with a 1/16-in.-diam hole and provided with 1/4-in. 30,000-1b autoclave tubing fittings for the introduction of helium purge. & - s 2 & 263 A similar tubing connection is made benesth the O-ring seals for the connection to vacuum pump No. 2 or the helium supply (see ORNL drawing 10301-R-152-E). In operation, the transport container is first inserted into the seal until the lower end is below the two O-ring gaskets, the removal valve being closed. Helium is then introduced between the O-rings, and the space between the seals and the removel valve is evacuated by vacuum pump No. 2. After helium is introduced into the space, the removal valve mey be opened end the transport container inserted into the transfer box. It is to be noted that the removal tool is also & legktight fit into the capsule removel seal., 7.3.8 Capsule Trensporting Equipment After tegking a sample from the pump bowl, the sample capsule is pleced in a gas-purged leaktight compartment of a transport container. This container is then withdrswn from the transfer box up into a lead- shielded transport cask, using a specia.l t00l., The cask is then taken to the anelytical lsboratory. 7.3.8.1 Semple Transport Container. The sample capsules are trans- ported in & 30bk stainless steel container assembly, 1.367 in. OD by 18-13/16 in. long, maintained in a vertical position for both loading and shipping. fThe sample capsule rests in a compartment in the bottom, gbout 7/8 in. ID by 6 in. long., The .compartment fits inside the con- teiner, and vhen the conteiner is turned by & special tool, is joined to it by threeds at the bottom of the assembly. Double O-ring, neoprene ‘gaskets seal the joint. The bottom of the compartment is notched to fit over lugs on & poSitioning Jig in the bottom of the transfer box to keep the compartment from turning i-rhen the container is roteted to make or break the threaded joint (see ORNL drawing 10501—R-osofiE) 'I'he upper portion of the transport container is filled with an 8-1/l+-in.-1ong plug of lead for shielding in the transport cask, and the upper end has a vertical l/h-in. threa.ded. hole and transverse 5/16-in.- diam hole for a la‘tching pin, as will be discussed subsequently T7+.3.8.2 Transport Conteiner Removal Tool. The special tool used to insert and remove the transport container and to rotate it inside the 264 trensfer box is 1-3/8 in. in diameter by ebout 53 in. long. A 1/2-in.- N diem rod extending through the handle is threaded with 1/4 in., x 20 UNC - threads at the bottom to engage the threads at the top of the container. A T/16-in,.-wide slot on the bottom of the tool fits over a projecting lug on top of the carrier tube to prevent relative turning. The tool is long enough to extend through the transport cask, the removal velve on top of the transfer box, and into the box for joining to the tra.nsport container (see ORNL drawing 10301-R-050-E). | T.3.8.3 Transport Cask. The transport container, with the enclosed semple capsule, is drawn upward from the transfer box into a shielded trans- - port cask, as shown in Fig. 7.5. The removal tool, described gbove, is . then disengaged from the transport container. The cask consists of a 25-in. length of 18-in. sched-1l0 austenitic s stainless steel pipe with 3/8-in,~-thick flat plates welded to the ends. A 17-1/2-in. length of 2-in, sched-160 pipe at the center serves as the transport container compartment. Two lugs project from the top of the ~ cask at each side of the central hole. Each lug has a 5/16-in.-diem hole through which & spring-loaded latching pin operates to engage the corre- sponding hole in the lug at the top of the carrier tube. The pin is posi- tively locked in place to prevent accidental removal or spills from the cask (see ORNL drawing 10301-R-051-E). . The cask is completely filled with about 2250 1b of lead to provide a minimum of 8 in., of shielding in &ll directions. The opening at the % top of the transport conteiner is filled with a lead plug 8-1/14 in, long. * The bottom of the cask is closed with en 8-in.-thick sliding lead door. Lifting trunnione are provided on each side of the cask, which weighs a total of sbout 2500 1b. Three casks are available for the MSRE. T.4 Containment During all phases of operation, the sampler-enricher system pro- vides a minimum of two barriers to the escape of radiosctive pé.rticles and gases, Thus, failure of any one component will not result in the ’ release of dangerous amounts of contaminants, as is briefly reviewed U PP L Ll Stainless . Steel Can ook n Z NNS.VE\\ \\N\\\\\\\\\\\\\\\\\\\\u\\\\\\\\\\\\\E\.\\\\V\\ N cavers s e s aan e PLOOALOO00 ae e s T A e e b Sv e ea ey Unclassified ORNIL. DWG 64-8823 e amasy e " N avavssreasnereny v e nh AN R R e AR R e AN R A AR n e E s N eee st banane bt 0 - s P A s ranstterrngsens o e s s A e e N ae Y B e A n e d b e A SN NNt EE NS AEhO s e e s e ' . . ' . 265 A ST A o P el o it N T TP T P T I Tl S dL LT osrrraaseersoeunnsnny sraneesediee ey iy eyt irerany . 0 sy e e nar s s a e e ey enaeecyyrnneniay e bbbk e e e s b h e erry Trensfer Cask for Sempler-Enricher Trensport Conteiner. Retainer Letch s .-......c e n ey e S S aiseserrEaTateenenaieee e e e e b Sliding e i i e v rreany v \N\\\\.\:N\ Lol Ll L e e 5 Figure T.5. Le Iifting Trunions Container Receptacle 266 below. (For a detailed description of operation of the system, see Operating Procedures, Part VIII.) When the sampler-enricher system is not in use, the operational valve in the transfer tube is closed. The space between the two seating surfaces in the valve is buffered with helium gas at a pressure greater than that in the pump bowl. If leakage in the valve does occur, the cap- sule access chamber at the top of the transfer tube is sealed with double O-ring gaskets with the space between the gaskets buffered with helium gas. If leakage should occur from this chamber, or from any of the flanged "N Joints in the transfer tube connections, the escaped gases will be con- tained in either the transfer box or the valve box. These gases are moni- tored for radiosctivity before being discharged either to the auxiliary charcoal bed or to the containment ventilation system. In preparing to take a sample, after the transport container with the empty capsule has been placed in the removal valve seal assembly and purged of air, the removal valve on the transfer box is opened. At this point in the procedure, the operationsal valve and the access chamber door remaln sealed, providing the requisite double containment barrier. After the transport container and empty capsule are placed in the transfer box, the removal valve is closed and buffered with helium gas. (The transfer box may then be purged of any entering air should this be necessary.) When the access chamber door is opened to latch the empty cgpsule to the cable, the operational valve remains sealed. This valve and the transfer box thus constitute two blocks to the escape of activity. The access chamber door is closed and buffered with helium gas be- fore the operational valve is opened to lower the capsule into the fuel = pump bowl. The door and the transfer box are the double barrier at this point. After the sample has been tasken and moved to the transport container in the transfer box, in the reverse procedure to that outlined above, helium purge gas sweeps any fission-product gases from the transfer box to the auxiliary charcoal bed. At the completion of the sampling procedure, when the fuel salt is contained in a helium atmosphere inside the sealed transport container located in the transport cask, the cask is sealed in a gas-tight compartment £=J 4} 267 for shipment to the hot-cell facilities at the analytical laboratory. Double containment is thus provided during the transport phase. f.5 Shielding Preliminary estimates indicated that after extended operation of the MSRE at 10 Mw, one 10-g sample of the fuel salt would have a radi- ation level of gbout 200 r/hr at a distance of 12 in, In the design of the sampler-enricher shielding it was assumed that one such sample would be in the apparatus and that, in addition, the deposits of the decay daughters of the fission-product gases, particles of fuel salt, etc., would smount to about 200 r/hr. Figure 7.6 indicates the estimated ap~- proximate dose rate at the surface of the shielding for varying thick- nesses of lead. The outside of the sampler-enricher valve box, transfer box, etc., is shielded with a minimum thickness of 8 in. of lead, mostly in the form of stacked lead bricks. As described in Section T7.3.7.4, the mani- pulator is shielded with 6 in. of depleted uranium. During maintenance, with no sample in the apparatus and the radiocactivity due only to re- sidual contemination, it is estimated that 6 in. of lead shielding is sufficient after a lk~day decay period. The sleeve opening through the reactor containment vessel shielding, through which the transfer tube passes, requires special consideration. As mentioned in Section T.3.5.2, the annular space between the sleeve wall and the transfer tube is filled with a 20-in. length of lead. In addition, stacked blocks of borated polyethylene, lead bricks, etc., are used to attenuate and absorb the beam coming through the opening. 7.6 Stresses The stresses in the valve and transfer boxes were investigated * using standard relationships. The design pressure was LO psig at room * Private communication, Ralph D. Frey to R. B. Gallaher, December 1963. Dose Rate at Surface of Shield - mr/hr 5 0.5 0.3 0.2 0.1l Figure 7.6. < 268 Unclassified ORNL INMNG 64-8824 sec Cooling Time 6 7 8 9 10 11 Thickness of Lead - in. Effect of Lead Thickness on Effectiveness of Sampler Shielding. 27 269 temperature, and 18,750 psi was taken as the allowasble stress in 30k stainless steel. 2 The epplicable ASME Codes are listed in Section T.2.6. Reinforcing ribs are uéed for the sides and cover plates and the openings are reinforced vwhere required. Investigation of the transfer tube indicated & maximum bending stress of about 9200 psi at one end..129 TT Cover-Gas and Ieak-Detection System . Helium is used in the sampler-enricher system to purge the sealed compartments'of air or cbntaminaxed gases, to operate the pneumatic door latches on the capsule access chamber door, and to pressurize, or buffer, the space between the double gaskets used throughout. A drop in the | helium supply pressure to the latter, indicating a leak, actuates the various interlocks in the control circuits. 'As shown in Fig. 7.7 (Instrument Application Diagram, ORNL'drawing D-HH-B-40505), helium is supplied to the fuel and coolent salt sempler- enricher equipment at 250 psig through lines 509 and 515, respectively; from line 51k in the west tunnel area (see Section.10). With but few ex- ceptions, all'heiium lines in the sampler-enricher system are l/h-in.-OD by 0.083-in,-well-thickness stainless steel tubing with 30,000-1b auto- clave fittings. All hélium supply lines have double check valves to pre- vent backflow, | | At the fuel-salt sampler-enricher control board, line 509 divides into lines 650 and 674. The former has a pressure-reducing valve, PV-650, which furnishes helium at 75 psig to 3-way solenoid valves HSV-652 and HSV-653, éach of which supplies three of the pneumatic clamps to close and latch the capsule access chember door. After the doors are latched, the 3-way valves vent the spent helium to the containment ventilation system, a8 will be described subsequently. The doors are unlatched and opened by the admission of helium through HSV-651, & 3-way valve also supplied from line 650. Line 67&, mentioned above, is provided with helium through a pressure control valvé, PV~-509, which reduces the pressure to 4O psig and supplies two headers, 664 and 683, which have branch lines to the various seals, iy st 270 _ iyl ‘ i @ \ d——— 3 , \ — T i esan s }:':KHB e i “é'} (o O < O . ] e ; Laws 1] . L - TD CONTAVRMERT AR $YSTEM ™ = 1 ( T - —@3—— ser Dwe ¥ DAA-B- GoSIS .—._—..._._.._.M C6s oo p 1 RUFFER = o LEAX SETECTOR 4 X r u & ) @ 3) neaver '—_(':"-') - \ W NEADER *! : ¥ oy , e i N [—)4 Chor e & ! . X : \f‘“ 9 (R | | A r ™ g : LS / <55 @ i Z I ;A LN Py T s | pd T srone 2 ' gses 1 (MY ¢ ¥ 70 FUEL SALT SYSTEM P , reeefny ame ! Lo gt A 5 gt Y < Y ¥ WomeeB gke Sag ¥ DAAE 40500 - Y H teypeemed ey - . - ' ' Q‘ ‘ Nilae MY ] i i d 1 T Y A Ao j D oy . »-(:n}-\“'a 3 -3 LTS PRRISURE VRSSEL ’ vw"nutwh’ LAWP . ” o T INETER NG £ Lamp o222 - VACUUM PUMP %L S m f 12€ I8 & [SLLUMINATOR JE ;-.-.. ..... HNATIE )y ] 4 = ! a5l e ESr. . t .‘ . T T Y 17 ! : (i ‘::: CAEdY) o (Oy-mmerecmmnmaen A e - f,..... o3 “ T r ' : W--T '.---..: r ---------- A\u, : : L ! ! i e §TARL o M*‘G) ' /_;'_\ ' < t 2 . - e ] M e = o ——— - @) mmimzzzzoontiossmdireessemebiooooooooooooooooooo - it ) ) . . ¢ T os FNErEN % —T ; e g e L ———— - - — - —(fE )..% s o5 -4;','.)...@ i ATCAPIAYR 3 3 T . 5 = R || " Lo : - —-——'—":"“3}—‘ : sagn - f : LEr{iar-Sird "‘E‘ ; (% -l §5E > -"-"(lh""":';'l) @ - -.‘ Mg i.m-rr J. " . t & ~ [ } o x 5 ettt > »- -— ,‘,:;-@ Y ' ) i e ' - \ ‘ ] G e o= = — — =¥l -~ -~--4=ii. -~"" NOTES- : m @ \ . 5 ( TAun I1=AS FAR AS PRACTICAL, ALL EQUIPMENT . : MRS BEEN SHOWN IN ITS AREA LCCATION, . . : ,,,,, HWHERE THIS WAS N2T DONE, THE AREA - - -@"*m *", HAS_BEEN NCTED BY A £y@scriPr AS Cla. OTHER SYMESLS ARE PER o O.R. Nk CP-8EP-21y REV . - N i W eMN o8 -—=- Z:"I @ """"""" “ o l | -~ ‘ 4‘;:;_ GPERATICNAL 3 @' """ e T T ST T T T T T T T T T T arp--—-- . VALVE & : ooty & 2= % EcC e ———— ey - x o fmm=pe ~riio) @ ~riss> m A 2 ~ : " . rood S RE&. INSTRUMENT APPLICATION TABULATIEN §if '3:“_';":"““ “ el . _(_g‘c‘e_)________. < )___ _.”"‘ INSTRUIMENT FLOW PLAN_ SYMECLS oK cA87-2-1 - ] &/ - it i CONTAIMMBNT AIR SYSTEM = (NST, APPIL, DIAGRAM 13-Ad-J- 4OK/K “‘ss: 1 gl ; - vACUUM PUMP®L o 'E‘ e e <5 ymm e ---'@"*emfi-"@ir, CFF GAS SYSTIM - INST. APP'L. DIAGRAM D:AA-8-40210 . o Avie y--at : - ZOVER GAS SYSTEM=NST, AFP'G. DIATRAM >-AA-8- €0301 TO RELUM HEATER $5 ree |1 FUEL SALT SYSTEM=INST. ARA'L DIATEAM V-AA-FG0FN0 58 DE. P B-AkP- 40503 ARTA 13 2 AZEA 4A = REFERENCE DRAWINGS - NO. 1 ; OAX RIDGE NATIONAL LABORATORY ¥ £ OPERATED BY < — UnioN CARBIDE NUCLEAR COMPANY Poct RE = i - OIVISION OF UNION CARBIDE CORPQRATION PuNRCTION ARTA TA £ Lr'-q' o % ""““"‘*:;“" - TO OFF GAS $YSTEM OAX RIDGE, TENNESSEE . ! ! 3 G . D-AA-8-408I < N ! mur)..-} . S1E Pwé. D-AA-B LIMTS ON DIMENSIONS UNUESS | Aforrew Sacr Reactor ExeEriieny et 7503 A [ CHALGE NOTicE W8 2852 [veesk b L__-_._._-.(..,,..,,-....J sene OTHERWISE 3rECt NO, REVISIONS DATE {aPPo] APPD I @ Liisy ooy @m FRACTIONS & SAMPLER ~-ENRICHER SYSTEM iretie— - . TCORA T BT T SUCTeD ""?'vu;ra & ] oA _ 59 ! - (oot me)-d i veerts & — o NS TRUMENT APPLICATION DIAGRAM . =M 2 Fof5 . 1 : . ’ NED | DAT "‘mnovm DATE | APPROVED | DA 10 Lo ) e e e - ANGLES & ?fi_&sn}m 46 PROVED e _,{ APPROVED ~SEekED A [—APFLOVED | OATE | "'mnovw'l‘ AL | ‘ iy : "5";';'!84 "“‘ RBGavaner!si-e2 | oAt g s e 1 Pump : SCALE: e D‘HH I B |40505] D | Figure 7.7. Sampler-Enricher Cover and Off-Gas System Flowsheet 1 ) | 4 ! " N {1 271 flanged joints, etc. Most of the branch lines contain a flow element consisting of a short length of capillary tubing, to restrict the flow should a buffered joint develop a significant leak. In this event, the pressure drop in either of the two headers, 66k or 683, would be sensed by pressure indicators and an alarm would be sounded. The branch lines and the data on each restrictor are tabulated in Table T.l. ILine 674 also supplies helium at 40 psig to line 672, which pro- vides a supply of purge gas for the transfer box. The relatively large flow is regulated through PV-672, rather than through a restrictor tube. Two check valves in series at the exit of the line inside the box pre- vent backflow of possibly contaminated gas. (The line between the check valves and PV-672 can be evacuated by vacuum pump No. 2 and the gas dis- charged to the containment ventilation system.) The cable drive box is supplied with helium at 40 psig from line 674, via line 657. This line is provided with a flow restrictor, as listed in Table T.l. The helium flows through the drive box to the cap- sule access chamber, and is vented through line 678, as discussed below. Iine 666, branching from line 67k, is provided with a pressure- regulator, PV-666, which reduces the pressure to 15 psig for the helium supply between the double O-ring seals at the transport container seal. 7.8 Off-Gas System Off-gas from the cepsule access chamber and transfer box is vented through vacuum pump No. 1 to the auxiliary charcoal bed. All other gas, some of which may pass through vacuum pump No. 2, is vented to the con- tainment ventilation system., All discharged gas is monitored for radio- activity'bbth at the sampler-enricher station and again in the MSRE gas disposal systems. All off-gas lines leading to the charcoal beds can be blocked with two valves in series. 7.8.1 sttem No, 1 The capsule access chamber is vented through line 678, which is provided with valves HCV-6T8 and HSV-6T8. Gas in the transfer box is vented through HCV-677 and line 677, which. joins line 678 to comnect to Table 7.l. Helium Supply Lines and Restrictors in Fuel-Salt Sampler-Enricher System Restrictor Max. Flow Rate® Inlet D oD Tube Iength® Line No. Equipment Supplied (ce/min STP) (psig) (in.) (in.) (in.) 650 Capsule chamber door latches 5000 75 0.012 0.060 10.8 655 Maintenance valve buffer 30 40 0.006 0.050 28 657 Cable drive box 5000 40 0,017 0.060 12,4 664 Buffer seals 30 Lo 0.006 0.050 28 o 666 Removal seat buffer 30 15 0,006 0.050 9.5 & 668 Operating valve buffer 30 40 0.006 0,050 28 669 Capsule chamber door buffer 30 L0 0.006 0.050 28 670 Removal valve buffer 30 40 0.006 0,050 28 2411 restrictors discharge at essentially atmospheric pressure. bA:I.l restrictors have tubing formed into a coil and contained within a 2-in, length of 2-in. sched-kL0 pipe capped at each end. All material is 304 stainless steel. o 273 the suction of vacuum pump No. 1, after passing the radiation monitor RE-678. The vacuum pump dischaerges through a check valve to line 5k2, vhich connects to line 521 ieading to the auxiliary charcoal bed de- scribed in Section 12.Lk.2. The vacuum pump is & W. M. Welsch Manufacturing Company "Duo-Seal" unit, Model 1402, having e cepacity of 140 liters/min STP end is driven by & 1/b-hp motor. The pump is located in a vented box at the rear of the sampler-enricher unit. 7.8.2 System No, 2 The pneumstic cylinders on the capsule access door latches exhaust through the 3-way solenoid-operated valves HSV-651, 652, end 653, through HSV-675 end line 675, past the radiation monitors RE-6T5A and RE-675B, and Joins the 9-in.-diam line 949 leading to the containment ventilation system described in Section 13. The box in which vacuum pump No. 1l is located is vented through line 660 to the contsinment ventilation system, via line 68k, A branch of line 684 draws gases from the vacuum pump No. 2 vented box. The valve box is vented through line 659 to the vecuum pump No. 2 box. A remotely operated valve in this line, HSV~659, permits the line to be closed to determine which of the compartments is the source of contamination, should this be indicated by radiation monitors RE-675 A&%B. ~Alr or conteminated gases in the removal tube assembly are drawn off through line 679 and valve HCV-679, to the inteke of vacuum pump No. 2. This pump discha.rges into the vented box in which it is located, to be vented through line 68k, mentioned gbove, - - Vacuum pump No, 2 is identical to the No. 1 unit » described gbove. Both pumps are oPerated only when the sa.mpler-enricher eq_uipment is in use. - 7.8.5 Exhaust Hood ~ An exhaust hood 15 located over the transport cask position on the sempler-enricher to draw off any fission-product gases which might es- cape. This hood is connected to the containment ventilation exhaust system, the alr being drawn from the high~bay ares, as described in Section 13. 274, 7.9 Electrical | . Electrical power for the sampler-enricher system»is supplied from the 25-kw dc-ac motor-generated set No. 4, via instrument power panel No. 2. In event of failure of the dc supply normally driving the motor- generator set, batteries can provide at least two hours of running time, as described in Section 19. The capsule cable drive motor is arranged for 110-v, single-phase operation. The 220-v, 3~phase power for the operational and maintenance valve-control motors is obtained from a static converter used to change ~ the single-phase power from the 25-kw motor-generator set to 3-phase, o Mineral-insuleted electrical leads are used at all points where wires must pass through the walls of the leaktight compartments. All L | electrical disconnects are located outside the containment aress. T.10 Coolant-Salt Sampler-Enricher System Selt samples are taken from the coolant-salt pump bowl in es- sentially the same manner as that used in the fuel-salt system. Samples are removed but gbout once a month, however, and single, rather than double, containment is sufficient in that long-lived radioactive materisl . is not normally present in the coolant-salt pump bowl. The same sampling capsules are used in the fuel afid coolant-salt . systems, see Section 7.5.1.2 and Fig. T.l. The transfer tube, capsule drive mechanism, cepsule latch, pump bowl intermals, including the sampling cage, are all identical to those used in the fuel-salt system. See Sections T.3.2 through T.3.5 and T.3.7.2. The 1-1/2-in. NPS transfer tube extends from the coolant-selt pump bowl upwards through the side of the penthouse to a dry box mounted in & "packeged" coolent-salt sampling unit. The dry box is a 30-in.-long vertical section of li-in. sched 40 pipe. The pipe is closed at the ” bottom with a pipe cap and at the top with a 150-psi hinged end clamped flanged Tubeturn closure having elastomer O-ring seals.. This dry box - houses the cgpsule drive unit. The box is provided with one rubber | QHJ glove, the opening for which can be sealed with an 8~in. hinged flange ‘ tn 275 similar to that used on the top of the box. A 1-1/2-in, NPS connection at the bottom leads to the two 2-in. Jamesbury ball velves (see Section 7.3.7.6) in the transfer tube, and & top connection is provided for the 1-1/2-in. ball valve for insertion and removal of the capsules. The box is also equipped with two 3-in.-diam quartz-lens viewing and illuminating’ - ports, helium and vacuum connections. See ORNL drawing 10533-R-002-E. ‘The dry box was designed for a full vacuum or for LU0 psig at 100°F in accordance with the ASME Code for secondary nuclear vessels.l@ The normal operating pressure is 5 psig. A system of six different keys and about nine locks is used on the velves, electrical switches, opening lstches, etc., to reduce the likeli- hood of using an improper opersting sequence. This system of "key inter- locks" operates on the principle that a key is used to unlock a device end also to galn access to a key which can be used to unlock the next step in the procedure. An electrical system sounds ar alarm if the pressures in the equipment are not suitsble for the next step to be undertaken. The sample capsules are inserted into the dry box from, end with- drawn from the box into, a porteble container which is used to transport the samples to the anslytical lsboratory in an inert atmosphere. This container is a short section of 1-1/2-in. pipe with a 1-1/2-in. Jamesbury bell vglve at the bottom and a Wilson, Teflon, sliding dynamic vacuum seal where the .'!./h-in.-d.ia.m relsing and lowering rod passes through the top cap. In brief, the samples are taken by first evacuating the glove and -_ the dry box by meens of the vacuum pump provided in the packeged system. - The gases are exhausted to the containment ventilation gystem filters and stack., The box is then purged with helium, after which the sample - 1s lowered from the transport' container which has been temporarily mounted on the ball valve on top of the dry box. The flange cover on the dry box glove 1s then opened, allowing the operator to insert his hand and to attach the capsule to the latch on the capsule drive cable. After the capsule has been lowered into the pump bowl end filled, it is retained in the transfer tube for sbout ten minutes to gllow the salt to g0lidify and the asctivity to decay. It 1s then raised into the dry box and the reverse sequence of procedures used to transfer the capsule to the transport container. The coperation is described in detail in Part VIII. s -serpentine coils to provide 706 £t 277 8. COOLANT-SALT CIRCUIATING SYSTEM 8.1 Layout and General Description The coolant-galt system transporte reactor heat from the fuel salt heat exchanger to the air-cooled radiator where the energy is dissipated to the environment by the discharge of warm air from the stack. The c¢oolant salt, or secondarj*, system circulates a lithium and beryllium salt, similar in physicalaproperties to the fuel salt but barren of fis- - sionable materials (see Table 2.1). The main components in the system are the fuel salt heat exchanger, located in the reactor cell and de- scribed in Section 5.5, the coolant-salt circulating pump and the radi- ator, both located in the coolant salt cell The coolant-salt circulating pump is very similar to the fuel salt pump described in Section 5.4. Both pumps use & T5-hp motor, but the coolant salt pump operates against a higher head of 78 ft, turns at a higher speed of 1750 rpm, and delivers only 850 gpm as compared to 1250 gom £or the fuel pump. Other differences are that the coolant salt pump does fiot'have the cooling shroud for the top portion of pump bowl, spray nozzles in the bowl for release of fission-product gases, and the'over~ flow tank. The pump bowl has a centerline elevation of 833 ft 6 in., and as the highest point in the coolant salt system, serves as an ex- pansion volume. It is located in what is sometimes referred to as the penthouse ares. ' Lo e | ‘The radiator has 120 tubes ,5'3/1L -in. diam x 30 ft long, arranged in 2 of heat transfer surface. The coolant- salt enters at 1100°F and leaves at 1025 F at 10 Mw design conditlons The éeommngngir.isnssuppliedf by two: 250-hp axial blowers located in the blower house and hav1ng a combined capacity of about 200, 000 cfm. The - leav1ng;air, heated at design conditions to sbout 300 F,.isfdischarged from the exigting 10-ft diam x 75-ft-high steel stack at the southwest - corner of Bldg..7503."To guard against f?eeiing of the coolant salt in re——— * . , _ MSRE literature occasionally refers to the coolant salt equipment as the secondary systen. 278 the radiator tubes on reduction of power or loss of circulation, quick- closing doors are provided for the radiator to close off the air flow, and the radiator assembly includes electric heaters inside the enclosure. A bypass damper and duct permits regulation of the air flow over the coil. The 5-in. pipe from the coolant-salt pump discharge enters the re- actor cell through a penetration on the south side and circles the cell on the east side to the fuel heat exchanger inlet opening to the tube side. At 10-Mw the coolant salt enters the enchanger at about 1025OF and leaves at about llOOoF. The exit coolant salt line circles the cell on the west side, leaves through a penetration on the south side at about the 836-1t level, and then rises to the inlet header at the top of the radiator. The coolant-salt piping has low points on each side of the radiator, therefore two l-l/E-in. drain lines are provided. These lead to the coolant-galt drain tank. A 1/2-in. bypass line vents gas from the top of the radiator when filling the system with salt. This line has no valves, the salt bypass flow being inconsequential. All fiarts of the coolant-salt circulating system can be maintained above the liquidus temperature of the salt, about 85OOF, by means of electric heaters. The heaters on the coolant-salt piping inside the re- actor cell are removable for maintenance in the same manner as pipe line heaters on the fuel salt system, see Section 5.6.4. Heaters for the coolant-salt system located outside the reactor cell can be approached for direct maintenance a short time after reactor shutdown. Pipe line heaters are attached tubular types with standard insulation. Heaters installed inside the cell wall penetrations can be maintained from the coolant cell side. The coolant-salt piping is anchored at the cell wall penetrations, at the coolant-salt circulating pump and at the radiator. The piping runs between these points are sufficiently flexible to absorb the thermal expansion. This arrangement eliminates the need for the rather elaborate " flexible support system for the pump, as is used in the fuel system, and also permits the radiator structure to be rigidly mounted. Auxiliary equipment for the coolant-salt circulating system includes the helium cover gas supply, the off-gas system, the bubbler liquid level h"? ¥y _279 system, the lubricating oil system for the pump, cooling water, etc. The coolant-salt drain tank for storing the charge of salt in the circulat- ing system is located almost directly beneath the radiator and is described in Section 9. o All saltfcontaining portions of the system are constructed of INOR-8, see Table 2.2, | 8.2 TFlowsheet The.coolént-salt circulating system and the coolant salt drain system are shown in Fig. 8.1 (ORNL Dwg D-AA-A-40881). Wheh 0perating at the 10-Mw reactor design power level, the coolant saltncirculafiing pump discharges about 850 gpm of salt at 1025°F and about 70 psig into the 5-in. Sched 40 line 200. At lower power levels the tem- perature'will increase and at zero power will be 1200°F to 1225°F. Line 200 enters the reactor cell and is connected through freeze flange.F-200 to the fuel heat exchanger, see Fig. 5.3 (ORNL D-AA-A-40880). Line 200 has three heater sections and thirteen thermocouples within the coolant cell, and twelve heater sections ahd seventeen thermocouples inside the reactor cell. The penetfation'through the cell wall contains eight heat; ers and seven thérmocouples.. The fuel system process flowsheet indicateé a future freeze flangé in the reactdr_cell at the wall penetration. This new flange would be requiréd'should it become necessary to replace line 200. B e | The coolant-salt leaves the heat exchanger through the 5-in. sched 40 pipe, line 201, at about 1,100°F and 47 psig. After passing through the freeze flahge FF-201, and the cell wall penetration, it returns to the coolant.cell.i Line 201 is provided with heaters, thermocouples, and has pfovisibns_fbr a future fréeze flange,'in the same manner as line 200, described above.~' After passing through a venturi, FRA-201, to indicate the flow rate, the coolant-salt enters the top header of the radiator at a pressure of about 36‘psig. The radiator has 120 tubes, 3/4 in. OD 0.072-in. wall thickness x 30 ft long, arranged in serpentine coils between two headers, to provide'a total of about 706 ft2 of heat transfer surface. The pressure et s b g 1 e 2 MEVISIONS ' CCN : T0 sEE boM :uo_— — _-_l l‘ || =23 EQUIPMENT o © - w < Wi a CELL COOLANT CELL T COOLANT DRAIN € COOLANT DRAIN TANK {com) QL WL oao-s RECEIVER TO OFF GAS AUXILIARY CHARCOAL BED A e e e i i . _ - | 280 v , LUBE OIt, SYSTEM ‘ tozser COOLANT CELL @ I & . P : . | HOOF " <3 T . 1 G ‘ B @ g - . * TWR ] I_ ,_ TO COOLANT 'SALT SAMPLER ’ ' I ™ meo! | we-4 — - W RADIATOR j (CR) ' COOLANT | PUMP DATA —_— @D - RADIATOR ' DATA * g cP 8 P31 “ | =<4 COOLANT | >~ PUMP | | ? i i | NO.2 DUCT i LINE BLOWER ! comnol. M8-2 i oNIT : COOLANT CELL | — —— | BLOWER HOUSE * LEGEND ' CAPPED UNLESS P8 IG I OR WITHDRAWING 852 LEVEL —r uomul. L/l .. @ 15 1 HEATER CONTROL CIRCUIT " GAS COOLANT PUMP NG. 3 ccp-3 - COOLANT SALT SYSTEM INSTRUMENT " GAS COOLANT PUMP DATA APPLICATION DIAGARAM ! - - 13-40- TYPE SUTORBILT 4N I ro g, [P phssmas srsi_ | ! VEL PROCESSING CELL |-2¥ S0 8cry FUEL SvHTEM FREEZE VALVES LPOWER o ne MOLTEN SALT REACTOR EXPERIMENT COOLANT SYSTEM - THIS DRAWING REFLECTS PROCESS FLOW SHEET ‘/(% AS BUILT REACTOR DIVISION WASTE oceo |, /’ ‘ CHANGES £or és oare__9=17-64 (WOR-2} | RELhprs fafes yy 1368 - OFF GAS FILTERS JOB 4334.0 AL D-AA-A-40881- C - o ' - | FIGURE 8.1 ‘ [ > > »y ¥ i 281 drop of the coolant-salt in flowing through the radiator tubes is 20 psi. There are 149 thermocouples installed, which includes one thermocouple for each tube so that a plugged flow passage can be detected. The re- maining thermocouples on the radiator inlet and outlet headers provide data for heat balances used to determine the reactor power. The radia- tor utilizes eight heater circuits. The radiator is cooled by a flow of 200,000 cfm of air supplied by two 250-hp motor-driven axisl blowers. The air is drawn through the louvered sides of the blower house and delivered to the radiator coil face at a pressure of about 10 in. of HEO' Each blower has a motor- operated axial damper which can be closed to prevent back flow. The air is heated about 200°F in passing through the radiator coil and, after passing through turning venes, is discharged up the 10-ft diam x 75-ft high steel stack. The stack has a pitotsventuri tube, ¥FI-AD3, to measure the air flow and to enable heat balances to be made on the heat rejection system. The by-pass damper and the radiator doors are used to adjust the air flow across the coil to establish the desired heat removal rate and, thus, the power level at which the reactor operates. The coolant-salt leaves the bottom header of the radiator at about lO25OF and 23 psig and returns to the circulating pump via line 202, a 5-in. sched 40 INOR-8 pipe. The heaters for the line are listed in Table 5.12, Section 5.6.6. The salt enters the bottom of the pump bowl where any entrained gases are drawn off. A 5-psig over-pressure of helium is maintained above the salt level in the bowl, the helium being introduced through line 512 and the liquid level bubbler lines. About 15 gpm of the 850 gpm discharge rate of the pump returns to the pump bowl by escaping through the clear- ances betweén the impeller and the casing, the so-called "fountain flow" described in Section 5.k.1.2. The pump operates against a head of 78 ft and the discharge pressure is 70 psig. The pump discharges info line 200, described previously as leading to the heat exchanger inside the reactor cell. ' _ The 1-1/2-in. sched 40 fill and drain, line 204, is connected to the low point of elevation in line 201. A similar drain, line 206, is provided for the low point in the radiator at the lower header. Both 282 of these linesihave freeze valves, FV-204 and FV-206, and connect to the gii coolant-salt drain tank through line 204. This line is provided with a reservoir, consisting of a 5-in. length of 4-in. sched 4O pipe with pipe caps welded on each end, which insures that & sufficient quantity 6f salt will remain behind after a drain to completely fill the freeze valves so that & seal can be effected. (See ORNL Dwg E-GG-C-40603). Each of the drain lines, 204 and 206, has one heater circuit and seven thermocouples on the circulating system side of the freeze valve. The coolant-salt drain tank is located beneath the radiator and has 3 sufficient capacity to store the 44 ft° of salt contained in the circu- lating system. The drain tank is described in Section 9, following. Line 205 is a 1/2-in. sched 40 pipe which connects the high point of the inlet line to the radiator, line 201, with the outlet, line 202, to vent the gas from line 201 when filling the system with salt. An in- significant amount of salt is by-passed through line 205. The pipe has one heater circuit and two thermocouples. Thirteen suxiliary pipes connect to various parts of the coolant- salt circulating pump. Lines 594, 595 and 598 are 1/L-in. OD stainless steel tubes carrying helium for the bubblers and the reference pressure for determining the salt liquid level in the pump bowl. The normal helium flow rate in line 594 is 0.15 liters/min, and in lines 595 and 598 is 0.37 liters/min. The solenoid valves in these lines are in the coolant cell and the hand control valves and flow indicators are in the special equipment room. | Line 512 is a l/h-in. OD steinless steel tube supplying 0.6 liters/ min of helium purge gas to the pump shaft annulus just below the lower shaft seal, to provide an inert cover gas, to provide off-gas to the radiation monitor, and to reduce the migration of o0il vapor to the coolant salt in the bowl. Off-gas is vented from the pump bowl at an estimated rate of 1.4 liters/min through the 1/2-in. Tine 528. The gases are at a pressure of about 5 psig and flow through a filter and a pressure-regulating valve, PCV-528. By controlling the rate of venting the gases, this valve es- tablishes the operatiné pressure in the coolant-salt system. Line 528 f Q;; continues to the vent house where, after passing the radiation monitor s} " # o i ] 283 RIA~528, it joins line 927, via lines 565, 557 and 560, to be vented through the filters and the off-gas stack. The small oil leakage through the lower shaft seal on the pump is swept away by 0.07 liters/min of helium that flows upwards through the labyrinth seal and out through line 526. The 1/2-in. pipe leads to an - 01l catch tank in the coolant-salt drain cell where the separated oil drains into a 55-gal stainless steel drum. The helium vent pipe con- tinues as line 526 through a hand valve, V-526, a filter, and a 30k stainless steel capillary restrictor which limits the flow to about 70 ccfmin. The vented gas Jjoins the above-mentioned line 528 for discharge through the filters and the off-gas stack. | The coolent-salt is sampled through line 998, which is a 1-1/2-in. sched 40 pipe rising vertically from the pump bowl and into the high bay area. Salt is dipped from the bowl and withdrawn through a ball valve, HCV-998, in the same manner as described for the fuel pump in Section T, with the exception that the lower activity level allows the coolant-salt " system to be somewhat less complicated. Iubricating oil is supplied to the pump bearings through the 3/k-in. line 753 at & rate of about 8 gpm through the 3/4-in. line T54%. The oil leaves the shield block through line 757, in which the oil temperature is monitored, and passes through an eductor to induce a flow of oil from the bearings through line 755. The combined oil flow leaves the cell through the l-in. line 756, and returns to the coolant-salt lubricating 0il system. | ILine 591 is a l/2-1n. pipe connecting the tqp of the lubricating 0il supply tank with the topmost passages of the bearing housing to equalize the pressure between the two points. The lubricating oil system for the coolantasaitzpump is essentially the same as for the fuel pump, - as described in Section 5.4.1.4. The coolant-salt pump is driven by a T5-hp, 1,750 rpm, Lho-v, three- phase electric motor., The motor is installed in a steel housing that will contain oil end radioactive gases if either or both were to leak through the upper seal in the bearing housing. The motor is cooled by 5 gpm of treated water supplied through line 832 and leaving through line 833. A microphone, XdbE, permits monitoring of the pump noise 284 level. The motor speed, SIA CP-G, electrical input, Eil, EvE, Ew-I, and temperaturés are also monitored. The radiator is cooled by a 200,000-cfm flow of air supplied by two 250-hp motor-driven axial blowers. Each blower has motor-operated damp- ers which close to prevent back flow. The air is drawn through the lou- vered openings in the blower house walls and delivered to the coil face at a pressure of sabout 9.9 in. HéO. The air is warmed about 200°F by the heat rejected from the cooling salt, and after leaving the coil passes through turning vanes and flows upwards through the 10-ft-diam x 75-ft- high steel discharge stack. The stack is provided with pitot-venturi tubes which can traverse the stack for flow measurements to establish heat balances for the heat rejection system, FI-AD (See Part II). The by-pass damper and the radiator inlet and outlet doors are used to adjust the air flow'across the radiastor coil face to fix the heat re- moval rate from the coolant salt and, consequentially, the power level at which the reactor operates. Two 10-hp axial blowers located in the blower house discharge 10,000 cfim each of air into the annular space between the radiator air duct and the building walls to prevent damage to the building structure and ra- diator duct. This is particularly necessary when the reactor is oper- ating at zero or very low power levels and the main blowers are off. N Ll H 0 285 8.3 Coolant-Salt Circulating Pump The coolant-salt circulating pump is identical in most respects to the fuel salt circulating pump. The two pumps were fabricated to.es- sentially the same drawings and specifications with the various parts and subassemblies supplied by the seme manufacturers. (See Section 5.k4) Development of the coolant pump, final assembly and testing proceeded at ORNL almost concurrently with work on the fuel pump. The pump bowl is the highest point of elevation in the coolant-salt circulating system and, similarly to the fuel circulating system, serves as a surge volume, as the point for pressurizing the system with the helium cover gas, and as a means of separating and venting of gases en- trained in the salt stream. The fuel and coolant-salt pumps are both centrifugal sump types, driven by direct-connected motors, and differ mainly in their hydrau- lie characteristics through having different operating speeds and im- peller diameters. Because of the lower level of radioactivity in the coolant-salt, the coolant pump has no provisions for cooling of the upper portion of the bowl, and does not include the "strippef" flow in the bowl for removal of fission-product gases. Unlike the fuel pump in the reactor cell, the coolant pump can be approached for direét main- tenance a short time after reactor shutdown, a feature which simplified flange bolting arrangements, electrical disconnects, pump bowl heater design, thermal insulation, etc. 8.3.1 Description - Fig. 2.3 serves as a general illustration of both the fuel and coo}ant sa1t?pumps1 (See ORNL coolant ?ump assembly Dwg F~2-02-054- 10062-B%). The general'locafiion of the pump in the coolant cell is shown in Figs. 4.4 and 4.5, - - L | The coolant pump has a deéign’capacity of 850 gpm at a head of T8 ft when driven\at_1750'rpm by a T5-hp motor. Other design data are given in Table 8.1 *ORNL drawings for the MSRE pumps have & different numbering system than that used for all other MSRE drawings. 286 3 a Table 8.1. Coolant-Salt Circulating Pump . Design flow: pump output, gpm 850% internal bypass, gpm 15 Design head at 850 gpm, ft 78 Design discharge pressure, psig e TO% Design intake pressure, psig ~ 5 Tmpeller diameter, in. 10.33 Speed, rpm 1750 ' Intake nozzle (sched 40), in. IPS 6 . Discharge nozzle (sched 40), in. IPS 5 - Pump bowl: diameter, in. 36 height, in. 15 s Volumes, ft3 Minimum starting and normal operating L.1 (including volute) Maximum operating 5.2 Maximum emergency (includes space above vent) 6.1 Normal gas volume 2.0 Overall height of pump and motor assembly, ft 8.6 Design conditions: pressure, psig 75 temperature, °F 1300 ’ Estimated radiation level at pump, r/hr 1 Motor: | : Rating, hp > Electrical supply (AC), volts 440 - Starting (locked rotor) current, amps 450 Type Squirrel-cage induction NEMA class B ILubricant (Calif. Research Corp.) NRRG-159 Electrical insulation class . H Design radiation dosage for electrical insulation, r 2 x 1010 *¥Actual capacity is between 850 and 940 gpm and maximum discharge - pressure is 75 psig at 1765 rpm. (See Ref. 8.3.1) * 287 All parts of the pump in contact with the coolant salt arelfabri- cated of INOh-B. The pressure-containing portions were designed for T5 psig and 1300°F'and in accordance with Section VIII of the ASME Un- 4T Code interpretation Cases 1270Nh8 and 1273N.50 The thermal stresses were eveluated on the same basis as for the fuel—salt'pump, see Section 5.4.%4 and Ref. 88. The coolant-salt pump is arranged in three principal assemblies: fired Pressure Vessel Code, the fotary element, the pump bowl, and the drive motor. The rotary element assembly includes the rotating shaft and impeller, the bearing housing and bearings, and the impeller cover plate and upper labyrinth subassembly. The bearings, seals, and lubrication and helium gas passages, are all of the same type and arrangement as in the fuel pump. (See Section 5.4.1.1). The impeller diameter is 10.33 in. and is providéd with the same type of impeller shroud as the fuel pump. Pump speed and noise fiickups are essentially the same as in the fuel system. _ The lubricating oil system for the pump is identical to that used for the fuel pump, although the heat rejected in the oil cooler is much less. See Table 5.6 and the lubrication system flowsheet, Fig. 5.25 (ORNL Dwg D-AA-A-40885). The same oil is used as a lubricant in both systems, see Table 5.7. The lubricating oil syétems are separate from each other, although located adjacent fo each other in the east tunnel area, with the exception that in an emergency Lines 762, 712 end the breather interconnectiomn, Line 601, allow either lubricating oil system to supply both pumps. : ‘Thé-pump bowl, pump volute and discharge thimble in the bowl afé almost identical to the fuel pump components. The thimble has a 4-in. 1eng£h of 1/4-in. OD tubing welded to the top to vent gas from the pfimp o discharge as the system is being £1lled with salt: A small flow of salt will return to the bowl through this by-pass during normael operstion. The "fountaein flow" of about 15 gpm, which escapes from the clearances bétweenfthé;impeller and the pump casing, etc., is about the same in both pumps; The coolant pump does not have the spray nozzles above the salt level in the pump bowl for the stripping of gases from the 288 pumped salt, as is required for release of fission-product gases in the fuel-salt system. (See Section 5.4.1.2) A 1-1/2-in. vertical nozzle is provided at the top of the pump bowl for the taking of salt samples and for adding enriched material. The sampler-enricher system is a simplified version of the fuel sampler- enricher system. The salt level in the pump bowl is sensed by helium gas bubbler tubes in the same manner as in the fuel pump, and as described in Section 10.9.1. The short tube, line 598, extends 1-5/8 in. below the center- line of the pump volute, or roughly %-3/8 in. below the normel operating level in the bowl. The long tube extends 4-1/16 in. below the center- line of the volute and is supplied with helium through line 595. The reference pressure is transmitted by line 594 through a connection at the top of the bowl. In addition, a float-type level instrument is used. This instrument is & special differential-transformer type de- veloped at ORNL, see Part II. The electrical signal is transmitted to both the data logger and, after conversion to a pneumstic signal, is recorded on the same instrument as the level indication from the bubbler tubes. Helium cover gas is supplied through line 512 and FCV-512 to the pump shaft annulus just below the lower shaft seal. Off-gas is with- drawn from the top of the pump bowl through line 528. Line 526 with- draws the oil-helium mixture leaking through the seals to prevent the migration of oil vapor to the coolant salt, in the same manner as in the fuel salt pump.- The pump bowl was fabricated with a l-l/2—in. overflow line nozzle but the connection is capped and not used. Protection-fréfikfifiéifiiling is provided through use of liquid level instrumentation. The coolant pump bowl does not have a shroud and a flow of cooling air around the upper portion. The level of activity in the cover gas is so low that cooling is not required. The pump drive motor is a T5-hp, Westinghouse? direct-connected type identical to that used on the fuel-salt pump except that the normal synchronous operating speed is 1750 rpm. Operation at different speeds 3 i 289 can be obtained by varying the frequency of the electric power supply through use of a motor-generator set which can be brought to the MSRE site. The pump motor is cooled by treated water flowing through stain- less steel coils heliarc welded to the motor can. The motor data are listed in Table 8.1. (Also, see Section 5.4.1.3) 8.3.2 Hydraulics The hydraulic performance of the coolant-salt pump was determined on a water test rig for impeller diameters of 11.6, 10.82 and 9.9 in.u9 Although the required design capacity of 850 gpm at 78 ft of head could be achieved with an impeller diameter of 9.9 in., a diameter of 10.33 in. was specified in order to provide a margin for error of about 10% in the system resistance calculations and for a 5% variation in flow between the water test pump and the MSRE operational unit. As shown in the characteristic curves in Fig. 8.2, the coolant-salt pump has a capacity of 850 to 940 gpm under heads about 10% higher than the design value of 78 £t .30 8.3.3 Stresses The operating stresses in the coolant-salt pump are no less severe than in the fuel-salt pump, and in some cases, required even closer at- tention. See Sections 5.4.3 and 5.4.4 and Ref. 88. 8.3.4 Pump Supports The coolant-salt pump is mounted in a fixed position in the coolant cell. The coolant-salt piping has sufficient flexibility to absorb the thermal expansion with the pump and radiator acting as anchor points. The flexibility of the piping system is discussed in Section 8.6.1. The pump is bolted to a 2-in.-thick support plate (See ORNL Dwg. D-CC-D-41516), which in turn is bolted at each end with eight 5/8-in. bolts to a 5-in. square box header beam 18 in. long. These two box - beams are welded to a 5-in. I-beam structure which is fastened with through bolts to the concrete wall of the coolant cell. Isomode vi- bration absorber pads are used under the wall mounting plates. (See ORNL Dwg. E-CC-D-41515) Pump Efficiency - % ¢ Shaft Horsepower Head - ft 290 Unclassified ORNL DWG 64-8825 110 / \ 100 Head N Predicted { Operating { 5 Zone ~ / aupmmn "-\ 70 - \\\\ 50 ,/(fficiency \\ 50 ’(-_—_—-—-—— — 10 Shaft Horsepower / / | 0 /—/ Impeller Dia = 10.330 in. / Speed = 1765 rpm 20 10 0 200 400 600 800 1000 1200 1400 Flow - gpm Figure 8.2. Performance Curves for Coolent-Sslt Pump r(fi wis g ‘the event of sudden loss of rgactor power . 291 8.3.5 Heaters The coolant-salt pump bowl has 11.2 kw of electrical heat applied in the form of fourteen 6-in. x 8-in. x 5/8—in.-thick flat-plate ceramic heater units of 800 w at 230 v capacity each. (See ORNL Dwg E-MM-B-40837). Six of the heaters are equally spaced at the bottom of the pump bowl and eight are arranged vertically around the sides, with the surface of the heater plate averaging about 1/2 in. from the outside surface of the bowl. The heaters are connected in parallel and mounted in brackets in & 304 stainless steel heater basket. This basket is hung by four hooks from the pump support structure so that the heaters and basket do not touch the pump bowl. The heater leads use fish-spine ceramic insulating beads 0.260-in. OD x 0.124-in. ID x 0.260 in. long. The electric power supply is through heater control panel HCP-4 and is adjusted by a Type 1256 Powerstat from O to 240 v. (See Section 19.7.4) 8.3.6 Thermsl Insulation The outside of the heater basket is insulated with 4.in. of Carey- temp high-temperature:insulation applied in a conventional manner. (See ORNL Dwg E-MM-B-40837). 8.4 Radiator One of the chief considerations in design of the MSRE rediator was that it be protected from freezing of the coolant-salt in the tubes in 131, 132 Giner jmportant de- ‘sign factdrs were that the radiator was rto be used in conjunction with air-handling-eQuipment already installed in Bldg 7503 as part of the 'ART‘program, that the heat dissipation rate be adjustable from zero to 10-Mw, end thet the unit must be capable of operating for long periods of time without direct approach for inspection Or'maintenance;l5l- The galt should move downward through the radiator as it is cooled. In general, the above considerations were of greater importance than de- signing for high performance characteristics. 292 - 8.4.1 Description A drawing of the radiator and enclosure is shown in Fig. 2.5. (Also, see -ORNL, Assembly Dwgs E-DD-A-40431 and E-DD-D-4O4T0). The radiator de- sign data are summarized in Table 8.2 7 .8.471%312C011. - The radiator coil has 120 INOR-8 tubes, 3/4 in. 0D, with 0.072-in. wall thickness, and each about 30 £t long.* The tubes are arranged in an S-shaped configuration, 12 tubes high and 10 tubes deep in the direction of air flow, as shown in Figs. 8.3 and 8.k. The tubes are spaced 1-1/2 in. on centers, and the rows are 1-1/2 in. apart, with the tubes staggered, as shown in Fig. 8.4. This arrange- 2 ment provides about 706 £t~ of effective heat transfer surface. Each vertical row of tubes terminates in & manifold. The ten mani- folds at each end of the coil join horizontal 9-in. OD inlet and outlet headers, to which the 5-in. coolant salt circulating lines are welded. The manifolds are 2-7/16-in. ID and fabricated of 1/k-in. INOR-8 plate. (See ORNL Dwg E-DD-A-LOT44). The plate was first formed into a U-shape and then cold-drawn with a die to form the nozzles for weld- - ing the 3/4-in. OD tubing to the manifold. The plate was then formed into a circular cross section and the longitudinal seam weld and pipe cap were added to complete the assembly. The headers were constructed in essentially the same manner except that the plate thickness was 1/2 in. The outlet header is bolted to the fixed radiator structure and is an anchor point in the coolant-salt piping system. The inlet header is supported with slotted bolt holes that allow movement of the header due to thermal expansion. (See ORNL Dwg D-DD-A-40438). The tubes are supported about every 4 £t by 3/L-in.-wide stainless steel strap hangers, as indicated; in Fig. 8.5. The tubing is suffi- ciently free within the hangers to allow longitudinal movement. Align- ment pins passing through the straps maintain the row-to-row spacing. *Extended surface tubing usually associated with air-cooled coils is not used in the MSRE radiator because less rapid heat transfer is de- sirable on sudden loss of reactor power to prevent freezing of the cool- ant salt in the tubes. b3 " C *i » ’ 293 { Unclassified ORNL: DWG 64-8826 T " 0.D. INLET 5" SCHD. 40, aESDER LINE 201 7 | 2-7/46" 1.D. MANIFOLDS (10) {20 S-SHAPED 3/4" 0.D. TUBES 9" 0.D. OUTLET HEADER x — - |“'—_—~“2 ':| 5" SCHD. 40, LINE 202 Fig. 8.3. Radiator Coil Configuration. e 12 TUBES/ROW ——— AIR FLOW NP 10 ROWS OF TUBES 294 Unclassified ORNL LR WG 54696R ‘41314 «— CLEARANCE t-1-1/ 2 —0ta=1-1/2~» D L - O ~ o N f)' T e AT A T /A~ —D O— —O ) D A O -© D t 1 o101 O }- CB- C> ) -i_LEARANCE P S - & @ f 3/4 -—O—-O0O—1- | N LT N 7 Y N ——-l-3/4 0.0. x 0.072" WALL Fig. 8.4. Radiator Tube Matrix. 295 Unclasgified ’ ENCLOSURE FRAME ORNL DWG 64-8827 { 0N / -/ - A\ L@ "ROLLER" OR PiN | gl lI Hi g \ N - vl O SUPPORT ANGLE U O TUBE O STRAP ALIGNMENT PINS Y.. LOOSE FIT -} C ol 1 L A — i! :i 1 i HEH = \ } ENCLOSURE FRAME " Fig. 8.5. Radiator Tube Supports. ™ 296 Table 8.2 Radiator Design Data Construction material INOR-8 Duty, Mw ' 10 Temperature differentials Salt, °F Inlet 1100; Outlet 1025 Air, OF Inlet 100; Outlet 300 Air flow, cfm @ 9.9 in., H)0 200,000 Salt flow (at average temperature), gpm 830 Effective mean AT, °F 862 Over-allgcoefgicient of heat transfer, Btu/ft"-hr-"F 58.5 Heat transfer surface area, £t2 706 Design temperature, °F 1250 Max. allowable internal pressure @ 125OOF, psi 350 Operating pressure @ design point, psi 75 Tube diameter, in. 0.750 Wall thickness, in. 0.072 Tube length, ft 30 Tube matrix 12 tubes per row; 10 rows deep Tube spacing, in. 1-1/2 Row spacing, in. 1-1/2 Subheaders, in., IPS, sched-4O 2-1/2 Main headers, in., ID (1/2 in. wall) 8 Air side, AP, in., H20 9.9 Salt side, AP, psi 19.8 H 297 _ Each of the radiator tubes is provided with a thermocouple to pro- vide warning of restricted coolant-salt flow in any of the passages. A total of 149 couples are installed ifi the radiator,'lao on the tubes and the remainder on the inlet and outlet headers -and tube supports. (See ORNL Dwg D-AA-B-40511). The insulation used for the thermocouples on the tubes is Fiberfrax Ceramic Fiber, Grade 970-F, manufactured for the Carborundum Company (Niagara'Falls, New York) by the Harlbut Paper Company. Although tests indicated that the small amounts of sulphur,- aluminum and lead in the insulation caused no significant attack on _ INOR-8 at elevated temperatures,l33 the insulation having been baked at 1600°F for four hours to remove volatiles prior to installation. 8.4.1.2 Enclosure and Insulation. - The radiator enclosure sup- ports the coil and provides a heated and an insulated Jacket around it during the periods when it is desirable to meintain the heat within the coil. The coil supports in the high-temperature regions consist of an inner 304 stainless steel frame made of 1/L-in,-thick built-up and formed structural shapes. This is covered with 16-gage stasinless steel sheets. The stainless steel frame is bolted to & carbon steel exterior structure, composed chiefly of 6-in., 12.5-1b I-beams anchored to the coolant cell structural steel framework. Slotted bolt holes allow for differential thermal expansion, Johns-Manville 1/2-in.-thick Marimite~23 insulation board is used between the stainless and carbon steel sections at points of contact to reduce the heat transfer to the latter. (See ORNL Dwg E-DD-D-h0472) The remainder of the carbon steel framework is protected from high temperature by EagleéPlcher Supper—Temp block 1nsulat10n up to 6 in. thick. (See ORNI,Dwgs E-DD-D-MOH?O and 40471) The portions of this insulation with surfaces which would have been swept by the air stream have protective covers of l6-gage 30h stainless steel. (See ORNL E-DD-D-uou'(o) | | Flow of air, estimated +o be about 30,000 cfm at the 10-Mw design power condltlon,'by—passes beneath the coil to cool the radiator support structure. The radiator doors do not cover-these by-pass openings. 8.4.1.3 Doors and Door Mechanism. - The upstream and downstream faces of the radiator enclosure are equipped with insulated doors that 298 can move downward in vertical tracks to provide a fairly air-tight seal to completely contain the radiator coil in an insulated and electrically- heated enclosure during the periods when it ié required to conserve the heat in the coolant salt system. The doors are 8 ft high x 11 ft wide, and each weighs about 1,770 1bs. (See ORNL Dwg D-DD-B-4OLLO) Each door moves on cam rollers in a U-sheped track, and as it reaches & nearly-closed position, raised areas on the tracks force the door toward the radiator enclosure, compressing a breided Inconel-wire, asbestos- packed gasket, mounted on the door periphery, against & sheet-metal spring seal mounted on the radiator enclosure. (See ORNL Dwgs D~DD-B-40HM5, LOu46, LOYWT and 4OWL9) | The door frame is made of 4-in. x 0.120-in.-thick square carbon steel tubing, reinforced internally with vertical carbon steel T-sections and angle-crdss braces. (See ORNL Dwgs D-DD-B-4OL4L1, LO4L2 and LOLL3) Door insulation is 4-in. thick Careytemp block covered with over- lapping sheets of l/l6-in.-thick stainless steel on the side facing the radiator coil. The exterior is covered with 1lO-gage carbon steel plate. (See ORNL Dwg D-DD-B-L4OLLL ) The doors are raised and lowered at a rate of 10 ft/min by a 3-hp,* 3,150 ft-1b, 5-rpm output, U. S. Electric Motors, Inc., Model 254U-50, gear motor mounted above the radiator enclosure, as shown in Fig. 2.5. The motor is connected to the drive shafts for the individual doors by e chain drive. (See ORNL Dwgs D-DD-C-4OL50, L0451, L4OL52 and LOLGS) Each door is equipped with a Fawick Corporation Model SC-1150 stationary field type magnetic clutch and a Stearns Electric Company Style EB Size 1004, 48-volt DC, magnetic brake, which permit the doors to be positioned independently of each other. Clutch and brake torques are 2,700 ft-1bs and 800 ft-lbs, respectively. Each door is suspended from its drive shaft by means of four 3/8-in. diam stainless steel wire ropes attached to two 8-in.-diam sheaves. (See ORNL Dwg D-DD-C-40454) The wire ropes have a breaking strength of ¥The theoretical horsepower required to raise the door is only . slightly more then 1 hp, but the motor was oversized to provide the "oreak away" torque needed to overcome the friction in the door gasket seal. 4 299 12,000 1bs. The four ropes are connected in pairs through two shock- absorbing springs mounted on the top edge of each door. A 2,310-1b fly- wheel, 39-1/2-in. diam x 6-1/2-in. wide, made of laminated steel plates, is attached to one end of each of the'door drive shafts through a Form- sprag Model FS-700/2.75 over-running clutch. (See ORNL Dwg E-DD-C-40469) The inertia of the flywheels limit fhe speed at which the doors would fall in case of a.loss of electrical power, or of a reactor scram. The time required for a door to close is estimsted to be about 3 seconds and the final velocity of the door about 6 ft/sec. (See Ref 15, Section VII, p 69) 8.4.1.4 Cooling Air Blowers, Ducting and Dempers. - Air is supplied to the radiator by two 250-hp Joy Manufacturing Company "Axivane' blowers, Model AR600-36D-1225, Unit X-709-29 driven at 1750 rpm by 250-hp General Electric "Triclad", direct-connected, induction motors, Model M6335-JY-1 Type M Frame 6335Z, 3-phase, 60-cycle, L4O-volts. Each blower is rated at 82,500 cfu et 15 in. E0 or 114,000 cfm with free air delivery. The normal discharge pressure at the reactor design power level of 10-Mw is 9 in. of H20, providing a combined capacity from the two blowers of about 200,000 cfim. The characteristic performance curve is shown in Fig. 8.9, and discussed in Section 8.4.3. EBach blower is provided with a four- bladed, motor-operated shut -off damper on the discharge which can be closed to prevent backflow through the fans. The blowers discharge into e 10 x 12-ft air duct leading to the plenum at the face of the radiator coil. v‘ o _ | A byfipass duct beneath the radiator contains & vertical-louvered damper which can be adjusted to control the flow through the by-pass and, "therefbre, the air passing over the radiator coil. The entrance section to the by-pass duct is 2 x 10 ft and about 5 £t long, and leaves the main duct at an angle of about 60° with the horizontal. The center section contains the by-pass damper and is 3 x 7T £t in cross sectional area. The exit section is identical to the entrance section. | Air leaving-the.rediator or the by-pass duct passes through turning venes to direct it up the 10-ft-diam x 75-ft-high free-standing steel stack. A pitot-venfuri tube is located near the top of the stack to measure the air flow rate. 300 The air ducts are fabricated of stainless steel sheet. These ducts are contained within another duct to form an annulus through which cool- ing air is passed to cool the inside ducting to prevent excessive warping and buckling. The annulus air also protects any nearby concrete from overheating at low reactor power levels when the exit air from the radi- ator coil may be as hot as l,OOOOF. Air for the annulus is supplied by two 10-hp, 1750-rpm, Joy Manufacturing Company Series 1000 "Axivane" fans, Model 29-1/4-21-1750, having a capacity of 10,000 cfm each at 2 in. H0 static discharge pressure, as indicated in the performance curves shown in Fig. 8.6. After cooling the annulus the air joins the air from the radiator for discharge up the stack. 8.4.2 Stress The radiator tubes were designed for a maximum internal pressure of 350 psig at 1250°F. The maximum combined thermal and mechanical stress, which includes the effect of wind pressure, was found to occur at the outside circumference of the tube and calculated to be 5,224 psi. (See Ref 15 Section VII p 46). As indicated in Table 2.2, the maximum allowable stress in INOR-8 at 1100°F is 13,000 psi and at 1200°F is 6,000 psi. Stresses in the headers, tubes and piping due to the internal operating pressure of T5 psig was investigated and found to be only about 785 psi. (See Ref 14 Section VII p 47) The radiator was hydrostatically tested at 800 psi and pnemmatically at 670 psi.l34 | Design studies were made of the stresses in tubing supports, headers, doors, and other members and found to be well within allowable limits. (See Ref 15 Section VII pp 48-59 and pp 60-69) Shock loads on the structure when the radiator doors are dropped was calculated to be about 1,980 1bs. The wind load on the closed upstream door produces a maximum stress of 8,550 psi in the carbon steel T-sections when the pressure difference across the door is 15 in. H20. 8.4.3 Performance At 10-Mw reactor power level the coolant--gsalt enters the radiator at llOOOF; at zero power the entering temperature is 1200°F - 1225°F. The coolant:--salt temperature leav1ng the radiator is about 1025 F at 10-Mw and is 1200 °F to 1225 F at zero power. Static Pressure -~ in. H20 o 301 Unclassified ORNL DWG 64-8828 Joy Mfg. Ccmpany 2 Model 29-1/4-21-1750 ¢ L Series 1000 Axivane Fan \ \ Static AN ANV \ \\ \ :\:\\\\A 2\0 1 \\\l}\xA g AN A 11 )L\ ) LU | | " Volume - cfm in thousands Figure 8.6. Characteristics of Radiator Duct Annulus Fans 302 At the maximum load conditions the effective log mean temperature difference is 862°F, the salt film coefficient is about 3,420 Btu/hr- ftg—oF, the air film coefficient is about 61 Btu/hr-ft2-oF, and the over- all heat transfer coefficient is about 58 Btu/hr—fte-oF. (See Ref 15 part VII pp 8-25) The effective heat transfer surface of T06 ft2 thus provides a calculated capacity of 10.4 Mw. Inasmuch as the air film resistance is about 95% of the total re- sistance to beat transfer, the overall coefficient is strongly influenced by the air velocity over the tubes. At partial loadings of the reactor, the air flow will be regulated by the by-pass damper, by changing the radiator door position, and by on-off control of the blowers. The pres- sure drop due to the flow of air through the radiator coils is a function of the flow rate and this, in turn, effects the static pressure at the blower outlets and the blower capacity. The interplay of these several variables on the air temperature leaving the radiator under various load- 135 ing conditions is surmarized in Fig. 8.7, assuming stepless control of the air flow over the coil. If the cooling air enters the coil at 1OOOF, at the 10 Mw design power condition, the leaving air temperature is about 3OOOF. At lower power levels the exit air temperature is higher, being about 450°F at 4 Mw. Below this power level the exit air temperature increases sharply, and is estimated to be about 800°F at 1 Mw and 1000° to 1100°F at power levels below 0.5 Mw when the air flow rates are relatively small. There are many possible combinations of mode of blower operation and radiator door and by-pass damper positions which will hold the reactor power at a given level. One set of combinations is summarized in Table 8.3.136 The effect of the various step-wise adjustments on the air flow was estimated, as illustrated in Fig. 8.8.13% There is some disparity between values in these two studies but this is not of concern because experimentation with the actual system is necessary to establish the best procedures. Preliminary testing of the blowers, radiator doors and by- pass dampers has indicated that the static pressure losses in the system may be substantially less than the estimates used in the studies, de- monstrating further that the best combinations for stable operation, Unclassified ORNL DWG 64-8829 303 / /7 / Y/ / 0.8 1.0 0.6 0’4 Fraction Reactor Design Power 41 / \ N\ | PNV e " I N\ V[® \\\\\\ i \ ! L — \\\\\\ \\\\\\ o ° © 3 o © o o o o o-o~ X ay/qi1 ‘zojeyrpey y3noay] 93ey MoTd SseW IV (e i ] 1 i 3 i 1 i . 1 s i © o o o o o o O N @ i ™~ i =i n-oa X WID ‘aojerpey ysnoayl a3y mold 1T (q m — 1 - 1 i 1 i 1 i i o © O ~t o~ o -4 0o%H -up ‘xojeypey ssoxoy dv ary (9 L i 1 i 1 | ' i " 1 . } o o o o Q o o S 8 o 3 S m -4 L] (2,001 = °*dwey 327uI aATV) 4, 9 faanjeasdway 391InQ Ay (P Rediator Air Flow Characteristics Figure 8.7. Air Flow Rate - c¢fm in thousands 304 Reasctor Power Level - Mw Figure 8.8. Radiator Air Flow Characteristics at Various Steps in Load Reguletion. Unclassified ORNL DWG 64-8830 , - Two Fens jo——— One Fan Running Running ” | Total Fan Output 200 Flow Through Main Bypass 160 / Total Fan Output 120 ) rov { fl\' Through | i Bypass in Rediator 80 / Flow Through Minimum Power Rediator Attaingble with One Fan Running Lo / - 0 ] 0 2 L 6 8 10 305 particularly at reactor power levels below 1 Mw, will have to be de- termined in the field. Studies were also made of the operating sequences for rapidly changing the reactor power from low to high levels while maintaining the stability of the system and the required condition of constant fuel salt temperature leaving the reactor.¥® In these studies the system was sim- ulated by an analog com.puter.137 Ioad changes are made manually using a single, spring-return type load demand switch to increase or decrease the power. The switch actuates the programmed control for the radiator doors, blowers and by-pass damper, essentially as outlined in Table 8.3. In increasing the reactor loading from, say, 1 Mw to 10 Mw, the initial condition will be with the radiator doors about 35% open and the by-pass damper fully open and one blower in operation. Manipulation of the load demand switch first causes the radiator doors to be opened to their limit. A further increase in load is obtained by closing the by-pass damper. A still greater load demand starts the second blower and at the same time opens the by-pass damper again. These procedures will be reviewed during the preliminary testing of the reactor system. The characteristics of the axial blowers supplying the cooling air are as indicated in Fig. 8.9. Parallel operation of the two blowers under certain loading conditions can lead to unstable conditions with possible surging of the load distribution between the two blower driving motors. As indicated in Fig. 8.9 this is most likely to occur at about 100,000 cfm air delivery and would tend to be avoided by using one blower at 100% of capacity rather than two at reduced capacity. General operat- ing characteristics must be determined from the actual system. Analog computer studies were made to determine the freezing time for stagnant salt in the center of a radiator tube. Under design con- ditions, with the maximum air flow, the estimated time was about 50 138 seconds. *In the "starting mode" of operation at reactor power levels below 1 Mw, the nuclear power is held constant. In the "run mode", at power levels above 1 Mw, the fuel-salt temperature leaving the reactor is held constant. 306 Unclassified ORNL DWG 64-8831 Model: ARG00-360D1225 Air Density: 0.0697 l'bs/ Discharge Duct: 4.5 x 5 £t Blede Setting: u-1/2 Joy Manufacturing Company \’ N\ Recommended System Resistance Limit for Parallel Operation & Static Pressure - in. H20 B | e Estimated Static N } Static Pressure Pressure Performsance 600 of a Single Fan \ Breke Horsepower / 400 \\ 200 7 0 0 4o 8o 120 160 200 240 Volume Flow - c¢fm in thousands Figure 8.9. Estimated Performance Both Radiator Supply Air Fans Opersting in Parellel. Brake Horsepower 307 Table 8.3 Possible Steps for Controlling Heat Removal Rate from the Radiator¥* Step ‘Heat Removal Rate, Mw Conditions 1 0.03 (Heat leak) Both radistor doors closed, bypass demper open, fans off. 2 0.13 Upstream radiator door closed, downstream radiator door open, by- pass damper open, fans off. 3 2.3 . Both radiator doors open, bypess dsmper open, fans off. 4 3.0 Both radiator doors open, bypass damper closed, fans off. 5 3.8 Both rediator doors open, bypass damper open, one fan on. 6 6.5 Both radiator doors open, bypass damper closed, one fan on. T 6.1 Both radistor doors open, bypass demper open, two fans on. 8 10.0 Both radiator doors open, bypass | demper closed, two fans on. ¥From Bef 136-p 1 308 8.4 .4 Heaters About 223 kw of electric heater capacity is provided inside the radiator enclosure. These heaters are used to preheat the system before the coolant--salt is added and to maintain the temperature above,85OOF'at all times that the salt is in the system. Tubular-type heatérs are mounted 3-1/2 in. apart on the vertical up- stream and downstream faces of the coil. These "Calrod" units are tri- angular in cross section, about 0.35 in. on & face, and are in straight lengths. There are twenty-four 48-in. lengths, with a capacity of 1,350 w each; twelve 82-in. lengths of 2,500 w capacity each; twelve 0-in. pieces having a capacity of 2,750 w each; and twelve pieces 102 in. long with 3,150 w capacity in each length; making a total of 133,200 w capacity in tubular heaters. The heaters are supported in vertical rows of six each in 304 stainless steel clamps. The heaters use 230 v, 3-phase delta-connected electric power supplied through induction regulators CR1, CRL, CR5 and CR6 (See ORNL Dwg E-MM-B-40802 and Section 19.7 of this report). Flat ceramic-type heaters are used in the horizontal positions on the baffle plates above and below the tube bundle. The 60 heaters are identical 7-1/2-in. x 18-in. flat plates with a capacity of 1,000 w each. The 208-v power is supplied through induction regulstors CR2 and CR3. The inlet header is in an insulated enclosure provided with fifteen h-in. x 12-in. flat ceramic heater plates of 1,000 w capacity each. .These are served by induction regulator CR7 and are rated at 230 volts. (See ORNL Dwg E-MM-B-40808) The outlet header enclosure is equipped with twenty-seven 4-in. x 12-in. plates of 550 w capacity each at 230 volts. Induction regulator CR8 supplies these heaters. (See ORNL Dwg E-MM-B-40809) A1l the ceramic- type heaters are mounted in 20-gage 304 stainless steel cans held in place by 16-gage clips. The ceramic heaters total 90 kw of capacity. The nichrome heater wire leads are heliarc welded to extension leads of No. 12 alloy 99 soft temper nickel wire covered with 0.330-in. 0D x 0.124-in. ID x 0.330-in.-long ceramic fish-spine beads. vl 0 v B L) s 209 8.5 Cell Wall Penetrations for Lines 200 and 201 The coolant-salt lines 200 and 201 pass through the reactor cell wall through special penetration assemblies which contain electric heat- ers, thermal insulation, radiation shielding for the annulus between the process pipe and the penetration sleeve, and a rigid support to serve as an anchor point for the piping. The penetrations for each pipe are essentially identical. The fol- lowing description of & penetration would apply to either. 8.5.1 Reactor Cell Sleeve The 5-in. coolant-salt pipe passes through an anchor sleeve which is mounted inside a reactor cell gleeve Jjoining the reactor cell vessel and the outer shell, or tank. (The space between the vessel and the shell is filled with a magnetite sand-water mixture, as described in Section 4.3.1.,) A 2h-in. sched 80 carbon steel pipe, averaging about 16 in. long, is welded to the L4-in.-thick portion of the reactor cell vessel at the lo- cation shown in Table 4.1. A 32-in. OD x 0.625-in. wall thickness pipe, averaging about 25 in. long, is welded to the outside 3/8-in.-thick tank wall, which also has 3/8-in.-thick stiffeners st this point. An ex- pansion joint, about 30 in. OD x 26 in. long, (Badger Manmufacturing Company'Mbdel 24 -6WT Series 50) connects the 24-~in. and 32-in. pipes to make & leak -tight joint and accommodates 3/8 in. lateral movement and 1/4 in. axial movement between the inner and outer vessels. (See ORNL Dwg D-KK-D-LOT11 and 4OT12) 8.5.2 - Anchor Sleeve 'The eoo1ant—sa1t 1ines 200 and 201 are each anchored on the reactor cell"end‘of'eech penetration. These anchors are designed to withstand the forces due to the thermal expansions in the primary and secondary systems.' . - A 20-in. sched 80 carbon steel pipe about 5 ft long fits inside the reactor cell sleeve, described above. The reactor cell end of this pipe has a welded cap through which the 5-in. NPS salt line passes. The pipe is welded to the cap by using a special 3-in.-long section welded into 310 the process line, this section containing a shoulder which permits a full penetration weld that can be inspected and stress relieved. This Jjoint is the anchor point in each line. The coolant-cell end of the 20-in. pipe anchor sleeve is welded to the 32-in. OD reactor cell sleeve described above. See ORNL Dwg E-GG-C-41855 8.5.3 Shielding The annular space between the 5-in. process line and the 20-in. anchor sleeve is essentially filled with l-in.-thick 304 stainless steel shield- ing discs for a distance of 8 in. on the reactor cell end of the penetra- tion. The annual space between the heater shell, to be described below, and the anchor sleeve has l-in.-thick firebox steel shielding discs for g distance of 12 in. The first eight discs are stainless steel because they will operate at a higher temperature than the remaining twelve. The discs are thermally insulated from the process pipe with a thin layer of Fiberfrax bulk ceramic fiber insulation (described in Section 5.6.6.3). Other voids inside the anchor sleeve are also filled with this insulat- ing material. See ORNL Dwg E-GG-Z-55498. 8.5.4 Heaters and Insulation With the exception of about 12 in. on the reactor cell end of the penetration, the process pipe inside the anchor sleeve is surrounded by electric heating elements contained in a stainless steel shell. The heaters are removable from the coolant-cell end of the penetration, although probably with some difficulty because of the radiation streaming through the opening. Four l/h-cylinder ceramic heating elements (for description see section 5.6.6.2) 12-ih., long, each with a capacity of 3,000 watts (at 230 v) provide the relatively large amount of heat needed on the reactor-cell end of the penetration to keep the unheated length up to temperature and to compensate for the heat conducted from the pipe wall at the anchor point. On the coolant-cell side of this heater section are four 12-in. long heater sections, each containing four l/h-cylinder heating elements of 300 watts capacity each (at 230 v).. Only one-half of each of the heater sections is used at one time, the other portion gerving as a spare. & 311 With the exception of the last heater section on the coolant-cell end, the heaters are contained in a 22-gage, 304 stainless steel shell, about 10 in. diam x 4 ft long. This shell is provided with spacers and lugs to hold the ceramic heating plates, the heater leads, and the thermo- couple sheaths, in position. The outside of the heater shell is thermally insulated with a 3-1/2-in. thickness of Careytemp 1600 éxpanded silica insulation, as described in Section 5.6.6.3. See ORNL Dwg E-MM-Z-51670 for geheral assembly of heaters and in- sulation. 8.6 Secondary Circulating System Piping and Supports The tube side of the primary heat exchanger, the coolant-salt pump and the radiator are interconnected with 5-in. sched 40 INOR-8 piping. With the exceptions of the portions of the lines 200 and 201 inside the reactor cell, all the coolant-salt piping is accessible for maintenance a short time after reactor shutdown end uses more or less conventional welded pipe Jjoints and methods of heating, insulating and supporting the piping. long radius (25-in.) bends are used where possible. The piping at the reactor cell wall penetrations, at the pump and at the radiator nozzles, is fixed in position, the thermal expansion being accommodated by the flexibility of the piping. All horizontal runs of biping in the circulating and drain systems pitch downward dt about 30.' The circulating system pitches to two low points, one in line 201 Justrdutsidé the reactor cell wall penetration, and the other in line 202 at the bottom outlet of the radiator. The two 1-1/2-in. sched 40 INOR-8 drains, lines 204 and 206, are connected at these points. o | The freeze'flanges,'freeze valves, pipe line heaters and thermal insulation for the coolant-salt piping are described and included in the tabuletions of the corresponding equipment in the primary éirculat- ing system, Section 5.6, in ofder to complete each of those particular sections of the report. 312 _8£§.l Piping Stresses and Flexibility Analyses The coolant-salt piping inside the reactor cell, lines 200 and 201, are sufficiently flexible between the anchor point at the cell wall and the heat exchanger nozzles to absorb the thermal expansion of the piping and the movements of the heat exchanger. The stresses in the coolant- salt piping were included in the flexibility analyses made of the primary piping, see Section 5.6.2. It is to be noted that the maximum stress in the reactor cell salt piping was determined to be about 7,700 psi at the coolant-salt inlet nozzle to the heat exchanger.lo5 The coolant-salt piping outside the reactor cell is anchored at the cell wall penetration and at the radiator and pump nozzles. See ORNL Dwg -E-GG-B-40T702. The major pieces of piping, all of which are 5-in. NPS, are: line 200 from the pump discharge to the cell wall penetration, line 201 from the penetration to the inlet header at the top of the ra- diator bottom outlet header to the bottom of the coolant pump bowl. Line 202 contains a 25-in. radiub return bend for the necessary flexibility, and it is in this bend that the maximum pipeline expansion stress of 12,818 psi oceurs.T3? This is within the allowable stress range of 32,125 psi as determined by the Code of Pressure Piping, ASA B3l.l.lO6 (Also, see footnote, Section 5.6.2) The expansion stresses in lines 200 and 201, which also contain 25-in.-radium 180° return bends, are 11,931 and 8,851 psi, respectively.l39 The forces and moments at the pump support plates and at the ra- 139 diator inlet and outlet nozzles are within the acceptable values. 8.6.2 (Coolant-Salt Piping Supports The supports for coolant-salt lines 200 and 201 inside the reactor cell are listed in Table 5.10 in Section 5.6.2. The 5-in. coolant-salt piping in the coolant cell is hung on con- stant-load Bergen supports to minimize.stresses during warmup of the system. Fach of these supports a preset load equal to the calculated weight of the piping and contents at that particular point, when the support spring is in the zero position. As the system is heated, the piping moves up or down at each position, as shown in Table 8.4. This ” P) 313 This movement is less than the maximum permissible movement of the hanger in each case so that no additional stresses are imposed on the piping by the supports. Additional information on each hanger is shown in Table 3.L. Table.8.4, Coolant Cell Salt Piping Supportsd MSRE . Bergen Preset . Maximum Calculated Support Nizg:r Location Number LoadP Mfigtggghfianfir Pipe Movement on No. & Type® Ibs 7 o Heating, in.C CCs-1 200 Near cell wall CSH-5 C-1 315 +1.25 +0.22 ccs-2 200 Bottom of 180° CSH-4 D-1 260 +1.0 +0.25 vertical bend cCS-3 200 Top of 180° CSH-3 D-1 180 +1.5 -0.50 vertical bend ces-b 200 Below coolant pump CSH-5 D-1 295 +2.0 -0.52 ccs-5 202 Near radiator CSH-4 B-1 210 +1.25 +0.31 ces-6 202 Bottom of 180° CSH-4 D-1 200 +1.25 negl. vertical bend ces-7 202 Top of 180° CSH-4 D-1 225 +2.0 -0.82 vertical bend : ccs-8 202 Below coolant pump CSH-4+ B-1 225 +2.0 -0.52 CCs-9 201 Near cell wall CSH-5 B-1 330 +1.0 negl. cCs-10 201 Bottom of 180° CSH-5 D-1 335 +1.0 +O .4k vertical bend ccs-11 201 Top of 180° CSH-4 D-1 210 +1.25 negl. vertical bend CCs-12 201 Near radiator CSH-2 D-1 135 +1.0 negl. a Constant-load supports. Bergen Pipe Support Corporation (New York, N. Y.) b Preset load is the expected load from weight of pipe and contents. ¢ Positive values are up and negative values downward. d See ORNL Dwg E-GG-E-41866. » .- AR 315 9. COOLANT-SALT STORAGE SYSTEM A storage tank is provided at the bottom of the coolant cell to per- mit complete drainage of the coolant-salt circuleting system. The coolant drain system consists of & drain tank, various drain and transfer lines, freeze valves, and the associated valving, electric heaters, instrumen-. tation, thermal insulation, ete. Since the coolant selt does not generate appreciasble afterheat when drained into its storage fiank, the heat removel system used on the fuel drain tanks is not required on the coolant-salt drain tanks. In other respects the tanks for the two systems are similar, see Fig. 2.6. Much of the equipment ifi the coolant-salt drain system is of conventional de- sign, since the coolant cell can be entered & short time after reactor shutdown for direct inspection and maintenance. All parts of the system in contact with the coolant salt are fabricated of INOR-8. The portable cans for transfer of coolant salt to and from the MSRE site are described separately in Part VII. 9.1 Iayout and General Description The coolant-salt drain tenk is located at the 820-ft elevation below the radiator and its ducting in the coolant cell, as shown in Figs. 4.4 and 4.5. (See ORNL Dwgs E-GG-D-41888 and E-GG-B-40T702) Two drain lines are required to completely empty the coolant-selt circulating system because of the piping configuration resulting from the requirement that the flow of coolant salt be downward through the radiator.'-EaCh'of these 1-1/2-in. sched 40 drain lines is provided with e freeze valve, which, on interruption of the cooling air flow against 'it, will thaw and cause the system to drain by gravity. During drainage the gas in the drain tank can be transferred to the top of the circulat- ing system, or it may be vented to the off-gas system through a 1/2-in. pipe leading past & radiation monitor and to the sbsolute filters and the stack. . | The 4O-in.-diam x 78-in.-high drain tank has a volume of about 50 ft3; there is approximately 4L £t3 of coolant salt in the circulating system. 316 The drained salt enters the top of the tank, and by means of an internal dip tube, is discharged at the bottom. This dip tube permits transfer of salt back into the circulating system by pressurization with helium gas introduced at a top conneétion. The tank is provided with a single-point liguid level probe and with weigh cells to determine the tank inventory. The coolant salt is brought to the site in 2—1/2-ft3 cans holding 250 to 300:.1lbs of the non-uranium-bearing salt. The charging station, where the cans are heated and connected to the system, is at the 852-ft elevation above the special equipment room. Removal of a shield block on the southwest corner of the roof of the room permits connection of a charging line from the cans to a permanently-installed 1l-in. flange at the 849-ft elevation, which is the terminus of a 1/2-in. INOR-8 pipe lead- ing to.a flanged connection Jjust above the coolant salt drain tank. The blank flange normally in place at this lower connection is removed and the permanently-installed charging line is connected. The charging line dips internally to the bottom of the tank so that salt can be transferred back to the portable cans through the same lines. 9.2 Flowsheet The coolant-salt drain system is included on the flowsheet for the coolant system, Fig. 8.1 (ORNL Dwg E-AA-A-40881). Salt is drained from the low point of the coolant-salt piping in the coolant cell just outside the reactor cell wall penetration through the 1-1/2-in. sched 40 line 204. The low point in the piping at the radiator outlet is also drained through a 1-1/2-in. pipe, line 206. The freeze valves in these two lines, FV-20k and FV-206, have their'exits joined by a tee with the branch outlet facing upwards and connected to a short, vertical length of W-in. sched 40 pipe with caps at each end. This res- ervoir, which has an overall height of about 7 in., is to assure a suf- ficient quantity of salt in the freeze valves after a drain to affect a good seal. The pipe from the top of the L-in.-pipe reservoir to the top of the drain tank, line 204, is 1l-in. sched 40, the smaller size being used to obtain the flexibility in the tank connections needed for proper operation of the weigh cells. 3’ L » i 317 \ One electric heater circuit and one thermocouple are provided be- tween the drain tank and the freeze valves. Each of the two freeze valves has three heater circuits, one in the center, one to control the shoulder temperature at both ends of the valve and one on the freeze valve reservoir. There is a thermocouple at each section of the shoulder heaters and thfee couples on the freeze valve itself. Salt is added to the drain tank through a 1/2-in. pipe, line 203. This line leads from a flanged joint at the top of the special equipment room to & flanged connection at the top of the drain tank, and, by means of a dip tube, to within about 1-1/2 in. of the tank bottom. Line 203 has one heater circuit and eight thermocouples. When not in use in adding or removing salt from the system, line 203 is blanked off both at the flange above the drain tank and at the connection near the roof plug. When salt is to be added to the system, a helium cyiinder is con- nected to the 3/8 in. tubing at the charging station, line 615. This line contsins & pressure regulator, PCV-615A, and upstream and downstream pressure gages. Line 615 then branches into two identical pressurizing stations, or tinits. In the following description of one of the stations, the line numbers for the other are given in parenthesis. Line 615 con- nects to line 611 (612) at the pressure control valve PCV-611 (PCV-612). Downstream of the control valve and the pressure gage connection, the line branches to flow through two valves connected in parallel, V-611-A (v-612-A) and V-611-B (V-612-B), one of which serves as a spare. Line 611 (612) continues-past a pressure gage connection and to a removable spool piece, which is used to meke the temporary connection to the port- ~able salt cans. , Hellum for pressurlzatlon of the drain tank qor salt transfer from the tank is supplied by the 1/2- in. pipe, line 511. The helium is fur- nished at 40 psig‘from_the_l/é-in. line 500 in the cover-gas system, see Section 10. A pressure regulator, PCV-511, limitd the helium supply pres- sure to the ténk to.30.psig. A throttling valve, HCV-5llB and & control valve HCV-511A, downstream of the regulator, are used to adjust the rate of transfer. The three valves are pneumatically opérated, with the throttling and control valve adjusted from the control panel. A check 318 valve, CF-511, is provided in the helium supply to prevent backflow into the\cover gas system. The handvalves, V-511A and V-511B, provide iso- lation of the gas supply valves for maintenance purposes. The coolant drain tank is normally vented to the off-gas system through a 1/2-in. stainless steel pipe, line 547, via line 527. The latter is connected to the top of the tank at the same nozzle as the helium pressurization gas supply. Line S47 contains a pneumatically- operated control valve, HCV-547, which is adjusted by & hand switch at the control panel. , When draining salt from the circulating system, the salt in the loop is exchanged for the gas in the drain tank through the 1/2-in. inter- connecting piping and valves, lines 527, 536 and 528. Line 527 contains a control valve, HCV-527, before its juncture with line 536 upstream of the control valve HCV-536. Line 536 joins line 528 upstream of the con- trol valve, PCV-528. Line 528 connects to the top of the pump bowl. This valving arrangement permits venting the gas from the top of the pump bowl through line 528 and 536. Line 536, and its valve, HCV-536, bypasses the control valve PCV-528, which is set to pass only about 1.k liters/min of gas into the system, and would thus have insufficient capacity when the flow is in the reverse direction as salt is being added to the circulating system. A detailed description of the filling procedures is given in Part VIII. 9.3 Coolant-Salt Drain Tank 9.3.1 Tank The coolant-salt storage tank is 40 in. OD x about 78 in. high, overall, with a wall thickness of 3/8 in. in the cylindrical portion. The torispherical ASME flanged and dished heads are 5/8 in. thick. The tank is mounted vertically on weigh cells by a support system described subsequently in Section 9.3.2. Other pertinent data are given in Table 9.1. | The tank and all its attachments are fabricated of INOR-8 and generally in accordance with ORNL Specification MSR 62-3. The tank was vi ky ty 4 319 designed for an internal pressure of 65 psig &t 13000F, and in accord- ance with the requirements of Section VIII of the ASME Unfired Pressure Vessel Codeh7 for primary nuclear vessels. The calculations of the stresses in the walls, heads, and nozzles were based on standard re- lationships (See Part IV Ref 18) and are within the allowable stress of 3500 psi at 1300°F for INOR-8..° The top head is penetrated by five nozzles, as listed in Table 9.1. A 3-in. sched 40 pipe provides an inspection port and access for a salt sampler. This nozzle is flanged with a 3-in., 150-1b, ring-joint, weld- neck flange and a mating blind flange having a lesk detector connection. The 1-in. nozzle for the drain connection, line 204, enters the top head at the center and extends approximately 1-1/2 in. above the lower head. A 1/2-in. sched 40 pipe, line 203, also extends through the top head and, by means of a bend in the dip tube, terminates at the center of the lower head. This arrangement is designed to reduce the amount of "meel" left in the tank after a transfer. The two lines are welded together at the bottom to provide stiffening. ILine 203 has a special flange just above the tank, see Section 9.4k, following. A 1/2-in. sched 40 nozzle in the top head is used for gas pres- surization and for venting. A 2-1/2-in. nozzle is used for insertion of the level probe, ILE-CDT. This instrument has two single-point con- ductivity type probes which indicates whether the salt is above or below points marking 5% and 90% of the salt storage volume. (See Instru- mentetion, Part II) 9.3.2 Supports and Weigh Cells The coolant drain tank is supported by two 4-in. NPS steel pipe columns resting on the coolant drain cell floor at the 820-ft elevation. (See ORNL Dwg E-FF-D-41503) The installation incorporates two pneumatic load cells (A. H. Emery Company) for determining the inventory of salt in the tank. _ : A ll/l6-in.-thick x 6-in.-wide skirt is joined with a full cir- cumferential weld to the top of the tankljust above the head weld. Twelve stainless steel hanger rods, 5/8-in.-diam x 8-1/2 in. long, are fastened by clevis~type couplings to this skirt and suspend the tank 320 Table 9.1 Design Data for Coolant-Salt Drain Tank Construction material Height, in. Diameter, in. OD Wall thicknesses, in. Vessel Heads Volume, ft3 Total Coolant-salt normal storage Design temperature, OF Design pressure, psig Nozzles, NPS (sched 40), in. Inspection port and sampler Salt drain line 204 Salt transfer line 203 Gas pressurization line 511 level probe, LE-CDT INOR-8 78 4o 3/8 5/8 ~20 ~il 1300 65 1/2 1/2 2-1/2 ./ 321 from the support ring above. The carbon steel support ring is about 41-7/8-in. OD x 6 in. deep, and is fabricated of 1-1/2-in. plate*. It has two arms about 20 in. long extending from opposite sides. Each of fihg'arms is suspended by three carbon steel hanger bolts,** 3/8-in. OD ‘i‘38-in. long, from a pneumatic lcad cell festing on a 3/4-in.-diam steel ball mounted on top of the support column. The columns pass through ‘holes in the above-mentioned support ring with a clearance of l/h in. on & diameter, an amount sufficient to allow proper operation of the weigh cells, but at the same time preventing the tank assembly from felling off the supports. The long hanger rods end the point support arrangement reduces the horizontal loading on the weigh cells to a neg- ligible amount. | To effect maintenance on a weigh cell, or prior to removal of a tank from the system, the weight of the tank must be removed from the weigh cells. To accomplish this, the ends of each support ring arms vare equipped with & jack bolt which operates ageinst a bracket on the subport columns, just below the arms. 'A slight lifting of the arms by these bolts permits unthreading of the three hanger bolts on each weigh cell. It may be desirable at times to remove the weight from the jack bolts, such as to prevent swaying when cutting a pipe. To provide for this a collar is installed on each support column just below the arms. The weight of the assembly can be lowered onto these collars by backing off on the jack bolts after disconnecting the weigh cell hanger rods. Further‘description of the maintenance procedures is given in Part X. 9.3.3 ‘Electric Heaters and Insulation The coolant-salt drain tank is heated on the sides by tubular .heaters totallng 11 kw, and on the bottom by ceramic flat-plate heater units totaling 6 kw. A like amount of heater units are installed as spare capacxty (See ORNIL Dwgs E-MM-B-51668 and E-MM-A-40832) There are thirty-two tubular heaters curved to a 20-13/16-in. radius installed on the tank sides in & 304L stainless steel frame. *ASTM-A-285~5TT Grade C fire box steel. *¥ASTM-A-193 Grade BT steel. 322 Bach unit is & Calrod heater 0.315 in. OD x T4 in. long, with a heated length of 60 in., sheathed in inconel, and rated at 2500 w at 230 v. In each case two heaters are connected in series, and with a supply voltage of 24l v, the actual capacity of each unit is 700 w, or 140 w/ft. The tubular heaters are arranged in 16 horizontal rows on L4-in. centers, with the two heaters per row connected in series. The 16 rows are divided into two equal groups, one termed the "top" section and the other the 'middle" section. Every other row is for normal use and the remaining rows serve as spare units. There are thus four rows of two Y working heaters each in each section, or a total of 5.6 kw/section, with the four rows connected in parallel. The spare heater leads are terminated in junction box CS-1, located at the 840-ft elevation. (See ORNL Dwgs E-MM-Z-51625 and E-MM-C-5166T) The sixteen heaters on the bottom of the drain tank, dnd'termed the "bottom" section, are flat ceramic heater plates about 7/8 in. thick and having a trapizodial shape roughly resembling a right triangle with an altitude of 14 in. and a base of 7 in. (See ORNL Dwg E-MM-B-40829) The heaters are rated at 750 watts each at 230 volts. Half of the units are used as spares, providing a total working capacity of 6 kw. All heaters are connected in parallel with the electrical leads for the spare group terminating in junction box CS5-1 in the basement regulstor area. The units are arranged radially in a 304L stainless steel support basket suspended from the bottom of the tank. The drain tenk is thermally insulated with two layers of 2-1/2-in.- . thick "Careytemp" 1600°F block insulation. A 20-gage 30LL stainless steel liner is used between the tubular heaters and the thermal insu- lation. The insulation is applied in a conventional manner since the unit can be approached for direct maintenance. 9.3.4 Thermocouples The temperature of the drain tank is monitored by thirteen thermo- couples. Two of these are located at the center of the bottom, two at the charging line nozzle, two at the drain line nozzle, and the rest are distributed over the tank wall, as shown on ORNL Dwg D-HH-B-40532. . One thermocouple on the bottom head, two on the top head (one from each Qfi; T 323 location) end one on the wall near the bottom, are connected to the data logger. One thermocouple from the wall near the midplane is recorded and the remaining eight couples are scanned and displayed. 9.4 Coolant-Salt Transfer Line 203 This line is used to transfer salt from the portable cans to the drain tank when adding salt to the system and for returning the salts to the cans when reprocessing is required. The line consists of a 3/8-in. OD x 0.035-in. wall thickness monel (or inconel) tubing portion which is installed only when making transfer operations. The tubing leads from the portable cans to a special flange at the 8L4o-ft elevation at the southwest corner of the speciasl equipment room. From this flange a per- manently installed 1/2-in. sched 40 INOR-8 pipe leads to another special flange located just above the top of the coolant-salt drain tank. 9.4.1 Upper Flange on Line7203 The 3/8~in. OD tubing from the portable cans is connected to a l/2—in. stainless steel, ring-joint flange. (See ORNL Dwg E-GG-D-55412) The tubing is inserted & in. through the center of the flange using compres- sion fittings. This flange mates with a stainless steel flange having the basic dimensions of a 1-in. 150-lb ring-joint, weld-neck flange, but is machined to attach a 1/2-in. sched 40 INOR-8 pipe. The side of the 1-in. flange is'provided with & 1/4-in. OD tubing connection through which hélium.purge gaé can be introduced. This arrangément is used to purge the line of éir before the salt transfer is made and also assures a gas space in the annulus between the tubing and the pipe wall to pre- vent the coolant salt from coming in contact with the stainless steel flange. - When Line 203 is not in use, the tubing to the portable cans is discomnected and a stainlesg steel blank flange is used to close the upper flange opening to prevent contaminants from entering. 9.4.2 Ilower Flange on Line 203 The l/2-ino INOR-8 pipe leading from the upper flange terminates in 324 a l/2-in. INOR-8 ring-joint, weld-neck flange Jjust above the drain tank nozzle. A 3/8-in. 0D x 0.035-in. wall thickness x 12-in.‘long piece of monel {or inconel) tubing is welded to the bottom center opening to ex- tend the line into the drain tank nozzle. (See ORNL Dwg E-FF-A-LOL53) The mating flange on the drain tank nozzle is a l-in. INOR-8 ring-joint, weld-neck flange bored to accommodate the 1/2-in. sched 40 drain tank nozzle. The side of this flange is provided with 1/4-in. OD tubing connections leading to the helium gas supply in the leak-detector system. As in the upper flange, this arrangement is designed to form an annulus in which the helium gas prevents the salt from contacting the gasketed Joint, where exceptional cleanliness is required when resealing the flange. When line 203 is not in use, the lower flanged Jjoint is broken.and the opening is closed by an INOR-8 blind flange that has a T7/16-in. OD INOR-8 rod 12 in. long welded to it to extend into the drain tank nozzle to serve the same purpose as the tubing extension mentioned above. The ring-joint is leak-detected during normal operation of the reactor. £ 325 10. COVER-GAS SYSTEM The MSRE cover-gas system supplies helium for use as an inert gas above the salt surfaces, as a carrier for removing fission-product gases from the system, as a pressure source for the transfer of salt from one vessel to another, as a means for control of the pressure within the system, and, in the leak-detector system, as a monitor for leaks in the mechanical joints. The helium introduced into the system must be essentially free of water vapor and oxygen (< 1 ppm) to reduce the likelihood of oxide pre- cipitation in the salt system. The cover-gas system consists of a helium supply, dryers, oxygen- removal units, a treated helium storage tank, and various valve mani- folds and distribution piping, as indicated in Fig. 10.1. 10.1 ILayout and General Description Helium is normally supplied from tanks mounted on a trailer parked at the northwest corner of the Diesel House, see Fig. 3.2. The tanks can be periodically refilled at the ¥Y-12 Plant area. Connections are made from the trailer to two parallel helium-treating systems and the treated-helium storage tank located in the second bay of the Diesel House. BEach of the two treatment systems consists of a helium dryer, a preheater, and an oxygen-removal unit. The storage tank has a capacity of 500 ft3 (STP). An oxygen analyzer continuously monitors the treated helium for residual oxygen. The treated helium is then piped to the various process areas. An emergency supply of helium is provided by six standard helium cylinders located in the second bay of the Diesel House. 10.2 System Requirements The primary requisite of the cover-gas system is to supply the quantity of "high-purity" helium necessary for use in the fuel and coolant salt systems, and the auxiliary systems. 140 250 psig HELIUM SUPPLY TRAILER 2400 psig SUPPLY L HEADER TO ATM, OXYGEN RUPTURE REMOVAL DISC UNIT /' 2w 350 psig DRYER\ 1200°F \ 7 TREATED HEL IUM SURGE TANK CONTAINMENT | REACTOR ()-% -7 CELL ARRANGEMENT AT CONTAINMENT CELL WALL TYPICAL FOR SUPPLY TO: FUEL PUMP SWEEP GAS FUEL PUMP LEVEL BUBBLERS FUEL DRAIN TANKS UNCLASSIFIED ORNL DWG. 84-€00 e ALEAK DETECTOR SYSTEM A / , ENRICHER-SAMPLER 250 psig HEADER :GRAPHITE SAMPLER RADIATION MONITOR f—qTO STACK RUPTURE DiSC ‘1"-50 psig oo tSPENT FUEL PROCESSING 40 psig LEVEL BUBBLERS HEADER | FUEL SYSTEM DRAIN TANKS oy COOLANT PUMP AND DRAIN TANK o) FUEL PUMP SWEEP GAS b PUMP OIL SYSTEMS Fig. 10.1. Flow Diagram of Cover-Gas System. ~ oce 327 The purge of helium through the fuel pump bowl was set initially at 3.5 litérs/min, and it was estimated that 1 ppm of 02 in a 3. 5-liter/min helium purge stream would precipitate 5.5 g of ZrO2 per year (equivalent to 18 g of uranlum per year). 1 Neutron irradiation of the fuel salt will produce about 10 cc/day of oxygen in the fuel salt system when the - reactor pewer_level is 10 Mw,llLE which is equivalent to about 2 ppm of 02 in a 3.5-liter/fiih helium purge stream. On this basis, it was de- cided that the oxygen contributed as &8 contaminant in the helium purge gas supply should be held to a value of near 1 ppm, present either as moisture or as 02 The total volume of helium to be supplled continuously by the cover- gas system is about 5.6 llters/mln, distributed as follows: Sweep gas to the fuel pump 2.4 liters/min Two fuel pump bubbler level elements 0.9 o Two coolant pump bubbler level elements 0.9 " Purge to the coolant pump 0.6 " Two overflow tank bubblers . 0.9 " Additional intermittent £fléws are used for pressurizing the leak-detection system, for the transfer of sait, or for replacing the cover ges for. the lubricating-oil tanks. The cover-gas system was designed on the basis that a treatment and supply facility w1th a capacity of 10 liters/min, when used in conjunction with a 500- £t3 (STP) treated helium storage tank, would be capable of handling the total demand. An obvious reQuirement in the treated-helium storage and distribution system is that it be as leaktight as possible to prevent the loss of helium or its contamination by inlesakage. 10.3 TFlowsheet The flowsheet for the cover-gas system is shown in Fig; 10.2 (ORNL Dvg. D-AAqAQHOBBA). All the major piping in the system is 1/2-in. sched-40 stainless'steel. The helium is normally supplied from trailer-mounted tanks contain- ing 39,000 3 (STP) at 2400 psi through the supply valve V-500A on line HIGH BAY AREA b ¥ (3€) (Cs8) CALIBR, : ‘ ‘ r CYLINDER | » 1 6-710 510. cu, FT1-0.035-55 mm FT-0.035-38- CYLINDERS . . ‘ ——— §T-06%-33 4T-068-88 ({OR-2} DRYER NO.2 dr-0.088-33 NOTES: | | | | | | | 1-ALL EQUIPMENT EXCEPT HELIUM TRAILER IS LOCATED IN DIESEL HOUSE FRESH HELIUM SUPPLY (TRAILER) He F 39,070 ST O FT, 2400 P8 700F 10-94$ x 2/ crunpEms THIS DRAWING REFLECTS AS BUILT CHANGES oate. 2-21-64 DEPERGNOE SAMYILES W, . Tl S S CAR RIDOE NATIONAL LABDAATORY COVER GAS SYSTEM PROCESS FLOW SHEET T D TID DEvel 15 THE FROFSATY OF UION CARMSE NUCLEAR COMPANY = BIVIMNON OF UNION CARMUSE SORFORATINN FIGURE 10.2 329 500 downstream of V-500A through valves V-5024 or V-502B via line 502. Two pressure indicators, PI-502A and PI-502B, show the emergency cylinder bank pressure. The supply line is provided with a pressure indicator and alarm, PIA-500E, which alarms at 500 psig. This is followed by & pressure- reducing valve, PCV-500G, which lowers the supply pressure to 250 psig. This pressure is monitored by a high-low'alarm switch, PA-500B, set at 275 psig and 200 psig. The supply line also has a 1/8-in.-0D tubing take- off, line 548, leading to the oxygen analyzer A02F5h8 through valves V-548 and the check valve CV-548. The supply line then branches into two parallel 1/4-in.-0D, 0.065-in. wall thickness, stainless steel tubing lines to supply the two helium- treatment stations. The identical branches contain a hand velve, V-500B (V-500A); a tee to a purge vent, line 505 (line 504); dryer No. 1 (No. 2); a tee leading to a rupture disc, line 507, to be discussed subsequently; a tee for a gas cylinder connection, line V-500C (V-500B); and an isolation valve, V-500D (V-500C). The dryers, preheaters, and oxygen-removal units will be discussed in Sections 10.5 - 10.8, following. The 1/4-in. purge vents, lines 504 and 505 mentioned above, are used to vent helium from cylinders which can be connected at V-500B and V-500C to backflush and regenerate the helium dryers. The vents combine into a single tube, line 505, which contains a flow indicator, FI-505, before the helium is vented to the atmosphere. The rupture discs in lines 506 and 507 are rated at 350 psig and provide overpressure protection for the helium-treating egquipment. These lines also contain high-pressure slarms, PA-506 and PA-507, which are set at 275 péig. | ' The two branches of the treatment system recombine as line 500, which is connected to a flow-indicating controller, FICA-500, and an air-operated control valve, FCV-500, which limits the supply of gas flow to 10 liters/ min. : , , | A second supply line to the oxygen analyzer, line 549, is taken off line 500 st this point through the check valve, CV-549, and through the stop valve, V-549. The treated-helium storage, or surge, tank is con- nected to line 500 via line 597. This 1/2-in. line contains a normally 330 open valve, V-597A, and a branch connection to valve V-597B, which serves as a temporary vacuum connection. A pressure gage, PI-He, on line 597 indicates the surge tank pressure. Downstream of the surge tank connection; 1ine 500 contains a pres- sure indicator, PI-500A, and a pressure alarm switch, PA-500K, which is set to alarm at a low pressure of 100 psi. DFollowing these instruments, the helium supply to the leak-detector system is taken off, line 51h. (This 250-psi supply line is routed through the water room and the elec- tric service area to the transmitter room.) The leak-detector system is described in Section 11, following. A branch from line 514, line 509, supplies the sampler enricher, the graphite sampler and the coolant salt sampler. (Line 509 tees off line 514 in the west tunnel and is routed through the coolant drain cell, the special equipment room, then to the high-bay area.) Line 541 supplies the graphite sampler; line 509, the sampler enricher; and line 515, the coolant sampler. The helium supply, line 500, then divides into two parallel lines, line 500 and line 605, each of which contains a pressure-reducing station set to lower the helium pressure to 40 psig. These control valves, PCV- 500C and PCV-605, have the usual isolation valves. After lines 500 and 605 rejoin, a pressure indicator, PI-S500M, and a high-low alarm switch, set at 48 psig and 30 psig, monitors the pressure in the continuing line 200 . Line 500 contains a check valve, CV-500B, ahead of a radiation monitor, RIA-500. The helium supply to the chemical processing cell, line 530, is taken off at this pcint. In the water room, line 508 branches from line 500 to & rupture disc, set at 50 psig. A pressure-relief valve is located in the vent line down- stream of the disc. The vent discharges into the ventilation duct through line 932. ‘A low-pressure switch in line 500 closes two solenoid valves in the helium purge gas supply to the pump bowl, line 516, to insure that back flow will not take place in that line in event the rupture disc blows. Line 501 branches off line 500 in the west tunnel area to supply the fuel and coolant -salt pump bubbler systems. Line 517 is connected to line 01 and supplies helium to the drain, flush, and transfer tanks in the drain tenk cell, see Section 6. This line contains a flow restrictor, o 331 FE-517, which limits the flow to 0.5 scfm at the 65% full condition. The restrictor is followed by & pressure control valve, PCV-517, which limits the pressure used for transfer of salts, see Fig. 6.1 (ORNL Dwg D-AA-A-40882). Line 517 is connected to the valve manifold, HCV-572, HCV-5T4, and HCV-576, which serve the fuel drain tank No. 1, drain tank No. 2, and the fuel flush tank, respectively. The control valves in each of the three lines, 572, 574, and 576, are followed by two check valves and a hand valve in series. (The check valves and the hand valves are contained in a pot in the electric service area, and the 1/%-in. line from each hand valve is run inside a 1/2-in. pipe to the drain tank cell wall penetration.) Pressure transmitters for measuring the drain tank pressures, PRA-572, PRA-5T4, and PRA-576, are located in each of the three lines downstream of the check valves. | As shown in the cover-gas system flowsheet, Fig. 10.l1, line 511 leaves 500 to supply the coolant drain tank. This line has the follow- ing valves in series: V-511A, CV-511, PCV-511, HCV-511B (throttling), HCV-511A (block), and V-511B. Line 512 branches off line 511 upstream - of the first valve to supply the coolant salt pump with helium. As shown in the coolent salt system flowsheet, Fig. 8.1 (ORNL Dwg D-AA-A- 40881), line 512 contains a hand valve, V-512, a check valve, CV-512, and a flow control valve, FCV-512, with a maximum ratelsetting of 1.47 liters/min. ' Line 510 branches off line 500 in the special equipment room and leads to the service tunnel to supply helium to the lubricating-oil storage tanks. As shown on the lubricating-oil system flowsheet, Fig. 5.25 (ORNIsDngDaAAfA—h0885),-iine 510 provides oil to the coolant pump ‘lube 0il tank through valves V-510A, PCV-510A1, CV-510, and V-510B. Line 513 branches off line 510 upstream of V-510A to similarly supply - the fuel salt pump lube-oil tank through valves V-513A, PCV-513A1, CV—513 and V-5l3B. The cover-gas system flowsheet, Fig. 10.2, also shows & branch line downstream of the line 510 takeoff,.llne 554 , for attaching a possible helium recycle SYStem. Another branch of line 500, line 516, supplies helium to the fuel- 332 salt circulating pump at a pressurfi of about 40 psig and a maximum rate of 0.085 sefm. Line 516 contains two solenoid valves, HCV-51l6A and HCV-516C; an indicating flow contréller and alarm, FICA-516; and a flow control valve, FCV-516, followed bj two check valves, CV-516A and CV- 516B, and a hand valve, V-516. The function of the two check valves and the two solenoid-operated valves is to assure that radioactive backflow cannot develop in this line in event of loss of pressure in the helium sup- ply. Line 516 then enters the reactor cell and goes to the lower gas in- let on the fuel-salt circulating pump. A capped tee is pfovided between the hand valve and the check valve to enable the check valves to be pres- surized in order to test leak tightness. BSee Table 5.1 for helium supply rates to fuel pump. The check valves in lines 516, mentioned above, are located in a con- tainment pot. The line is reduced from 1/2-in. pipe to l/h—in. pipe at the control valve and to 1/4-in.-OD tubing at the check valves. From the check valves to the pump, line 51€ is 1/4-in.-OD tubing inside 1/2-in. pipe to provide double containment for the portion outside the reactor cell and to protect the tubing inside the cell. 10.4 Helium Supply The helium supply trailer has 30 cylinders, each 9-5/8 in. diam by 21 ft long, with a total capacity of 39,000 £t (STP) at 2400 psi. At the maximum estimated rate of use, 10 liters/min, this is equiva- lent to a T6-day supply. The emergency helium supply consists of gix standard cylinders ar- ranged in two banks of three cylinders each. At a use rate of 10 liters/ min this would be a 2.1-day supply. However, by changing these emergency cylinders in banks of three, the emergency supply arrangement could be used indefinitely. 10.5 Dryers The helium dryers in lines 500 and 503 each consist of a vertical section of 2-in. 304 stainless steel sched-40 pipe capped at each end » 333 and with a 1/2-in. sched-40 pipe nipple welded to each cap, see ORNL Dwg E-JJ-C~-40855. The pipe section is about 41 in. long and ¢ontains a 30-in. depth of drying medium supported on & l-in. depth of stainless steel wool at the bottom and having about 1-3/8 in. of the same wool at the top. The wool is held in place by 1/8-in.-thick plates with 1/16-in.-diam holes on l/h-in. centers in & square pattern for a total of 37 holes. The plates are tack-welded in place. | The drying medium is Linde type 13x Molecular Sieve, 1/16-in.-diam pellets. Each dryer containé about 2-1/2 1b of pellets. Each dryer bed is designed for a flow rate of 10 liters/min (STP) and to decrease the moisture content of the helium from 100 ppm to < 1 ppm on 143 an on-stream cycle of 15 days. The actual moisture content of the helium supply is thought to be less than 10 ppm so the bed life should be well in excess of 15 days. | The dryers are to operate at 250 psig and 80°F. For mechanical strength considerations, however, the design conditions were taken as 400 psig and TOOF. Since conventional hydraulic testing could not be employed after final assembly, the units were pneumatically tested at 500 psig (see ORNL Dwg E-JJ-C-40855). The fiormal flow direction is upward through the bed. The dryers can be regenerated by purging with a downward flow of fresh helium while heat- ing the bed. Heat for the regeneration is supplied by two 500-w, 240-v strip heaters (Chromolox Cat. No. S. E. 2550) about 25 in. long strapped to the upper-poftiOnVOf the pipe 'section. The heat is controlled by thermocouples located on the pipe wall about 1 in. from the end of the 'heafiedtsection. The wall is heated to & maximum of 5OOOF. The purge flow rate is about 1.5_liters/min, the exit gas temperature at the com- pletion of the drying cycle is about 500°F, and the internal pressure during regeneration is a maximum of 10 psig. " The entire unit is insulated with 'l in. of magnesia insulation. 10.6 ' Preheater Fach of the preheaters in lines 500 and 503 is designed to heat a flow of 10 liters/min of helium to 75OOF, required for the oxygen- 334 removal units. The préheater consists of a 2-in. sched-40 stainless steel pipe section 10 in. long with flat plates tack-welded to each end, see ORNL Dvg. E-JJ-C-55485. Two 2%-w, 120-v curved Chromolox strip heaters, 8 in. long, are strapped to this shell. Two thermocouples mounted L4 in. from the end are used to control the temperature. The helium flow is through a 10-ft length of stainless steel tubing 1/4 in. OD x 0.035 in. wall thickness, coiled around the heater unit. The entire assembly is covered with 3/& in. of the heat-conducting medium, "High Temperature Thermon, " and insulated with 2 in. of high-temperature insulation. 10.7 Oxygen Removal Unitsg Identical titanium sponge-type oxygen-removal units are installed in lines 900 and 503 to assure that the helium flow to the cover-gas system contains less than 1 ppm of O Oxygen contamination of the 2. helium supply is largely the result of handling and should not exceed about 100 ppm. The average O, content may be about 10 ppm. As indicated in Fig. 10.?, the oxygen-removal unit consists of a l1-in. sched-5 titanium pipe 21 in. long filled with an oxygen getter of Electromet (Cleveland, Ohio) titanium sponge having a Brinell hardness of 125 and sized so that 100% passes a 5/8-in. mesh screen and 95% is retained on a 1/8-in. mesh. The pipe is mounted vertically, using lava spacers, inside 220-v "Thermoshell" ceramic heating elements (Cooley Electric Co., Indianapolis), of 1200 w total capacity. A stainless steel reflector, 0.005-in. thick, is tightly wrapped around the heating ele- ments. The heat reflector is surrounded by a 3/h—in. thickness of "Fiberfrax" QC-10 thermal insulation (Carborundum Company). The as- sembly is contained inside a b-in. sched-40 stainless steel pipe, with ring-joint flanges at top and bottom. One-half-inch IPS pipe nipples are provided at top and bottom for the gas exit and inlet (see ORNL Dwg E-JJ-C-562%0). The units operate at 250 psig with a temperature in the titanium sponge of 1200°F i_SOOF. The design pressure is 400 psig and fihe de- sign temperature of the pressure-containing 4-in. pipe is a maximum of C. 9 335 UNCLASSIFIED ORNL-LR—DWG 68585 THERMOCOUPLE N | ®— N = (1) GETTER TUBE ' THERMOCOUPLE ~—_| (@) HEATER, 1000 w NP (3) HIGH-TEMPERATURE INSULATION (@) PIPE, 4-in, SCHED-40 SS ® () FLANGES, 4-in. 1500-Ib SS, 26%in. WELDING NECK, RING JOINT @ ®) INSULATION 21in. G— (7) REFLECTOR THERMOCOUPLE — |3 |—THERMOCOUPLE THERMOCOUPLE —| | THERMOCOUPLE N THERMOCOUPLE ] -THERMOCOUPLE o= B)— Oma Fig. 10.3. Oxygen Removal Unit Cover-Gas System. 336 1000°F. Ieak tests were made in accordance with Par. UG-100 of Section VIII of the ASME Code,u7 using nitrogen at 700 psig. Helium leakage was less than 107 liters (STP)/24 hr. A chromel-alumel thermocouple is inserted in & well a short dis- tance into the bottom inlet of the titanium sponge. This l/8-in.-diam stainless steel-sheathed couple is welded to a trepanned hole in the lower flange and has compression-type fittings on the outside of the flange. Three 1/16-in.-diam sheathed thermocouple leads are inserted through the 4-in. pipe wall near the top through lava-sealed packing glands, "Conax" Cat. No. MPG - 1/16 in. Two of these chromel-alumel couples are located at about mid elevation between the titanium pipe wall and the heater element, and the third is at the top outlet gas pas- sage. Two 1/8-in.-diam chromel-alumel sheathed thermocouples are pro- vided on the outside of the 4-in. pipe. The two electric leads for the heater elements are brought through the 4-in. pipe wall near the top in individual seals, "Ceramaseal" Dwg 804A38878. 10.8 Treated-Helium Storage Tank A storage tank is provided for treated helium to take care of the intermittent periods when the helium demand is considerably greater than the normal continucus flow rate of 10 liters/min. The volume of the storage, or surge, tank is specified to be 27 ft3 so that two fuel salt transfers and two coolant salt transfers could be made without decreas- ing the helium supply pressure below 100 psig. The tank is an 8-ft long section of 24-in. sched-30 pipe of 34T stainless steel, capped at each end. It is designed for a working pres- sure of 250 psig and a test pressure of 375 psig. The design operating temperature is 80°F. The tank has a storage capacity of about 500 ft3 (STP) of helium. a & t 337 10 9 Bubblers for Indicating the Salt levels in the Fuel and Coolant Pump Bowls and Overflow Tank The helium bubbler arrangement used to indicate the level of salt in the pump bowls and the overflow tank is described in this section since it is closely associated with the helifim distribution system. In brief, the level is determined by measuring the gas pressure required to displace the liquid salt in dip tubes which extend below the surface of the salt in the pump bowls and overflow tank. The dip-tube pressure is measured by d/p cells,ireferenced to the pressure in the vapor space. 10.9.1 Ilayout and General Description The bubbler arrangements used on the fuel and coolant pump bowls and overflow tank are identical except for location and the containment of the fuel system. The fuel pump bubbler is described in the following paragraphs with the coolant pump and the overflow tank equipment and locations given in parenthesis in the same order. The fuel pump bowl is described in Section 5.4.1.2. As shown on the fuel system flowsheet, Fig. 5.3 (8.1), there are two bubbler lines, lines 593 (598)(599) and 596 (595)(600), and one ref- erence line, line 592 (594)(589). These lines are fabricated of 1/4-in.- OD x 0.065-in.-wall stainless steel tubing and are connected to the hO-psig helium supply, line 501, in the transmitter room. Each line has a block valve at the header and a throttllng valve to adjust the helium flow. All the bubbler lines are routed past dupllcate radlation monitors, ~R1lA- 596A and RlA 596B, through conduit to the special equipment room. In thls location the fuel pump and overflow tank bubbler lines have flow restrietors installed which limit the flow in lines 593 (599) and 596 ,(600)7to 366 cc/min (STP) and in line 592 (589) (the reference line) to 150 ce/min, when the helium'supplyrpressure is 25 psig. The three coolent “pump bubbler lines, 598, 595, and 594, continue to the coolant cell where similar flow restrictors are. prov1ded. 7 The fuel pump and overflow tank bubbler lines enter a containment tank (not required for the coolant pump lines) where each line has *two check valves in series (one check valve in coolant system). The check 338 valves are followed by solenoid valves as follows: line 592, HCV-593- B2 (line 594, HCV-595-Bl) (line 589, HCV-599-B2); in line 593, HCV-593- B3 (line 598, HCV-595-B3) (line 599, HCV-599-Bl); and in line 596, HCV- & 593-Bl (line 595, HCV-595-B2) (line 600, HCV-599-B3). (See valve tabu- lations in Table 10.1.) Following these valves, the reference pressure, line 592 (594%) (589) is connected to line 596 (595) (600) through a solenoid valve, HCV-593-B5 (HCV-595-B5) (HCV-599-B5), and to line 593 (598) (599) through the solenoid valve HCV-593-B4 (HCV-595-B4) (HCV- 599-B4). These cross connections are for equalizing the pressure across * the d/p cells, which are connected between lines 592 (594) (589) and 596 (595) (600), LI-596 (LI-595) (LIA-600), and between lines 592 (594) (589) and 593 (598) (599), LRA-593 (ILRA-598) (LTA-599). The last- mentioned d/p cells serve both as level indicators and as an input to recorders and an alarm system. As was mentioned in Section 5.4.1.2, & difference in 2 in. in the distance the two dip tubes extend beneath the surface of the salt in the pump bowls, 593 (598) is the shorter, may permit variations in the density of the salt to be noted. Both dip tubes extend to the bottom of the overflow tank since it is desirable to have duplicate readings on the quantity of salt remaining. A connection is made to line 592 (589) for the fuel pump bowl pres- sure transmitters, PRC-522A and PIA-522B, and to 589 for PIA-589 and PXM-581. Each of the lines, 592 (594) (589), 593 (598) (599), and 596 (595) (600) has a hand valve outside the cell wall penetration. The lines . to the fuel pump and overflow tank are 1/k-in.-OD tubing run inside l/2-in. pipe inside the reactor cell to provide double containment. 10.9.2 Containment Tank The fuel pump bubblef containment tank, or instrument box, is a pres=~ sure-tight container for the above-mentioned solenoid valves and d/p cells. The tank is fabricated of a 21-in. length of 24-in. sched-10S, 304 stainless steel pipe, with a flanged pipe cap at each end to give an overall length of about 44 in. (see ORNL Dwg E-JJ-D-55422). The de- - sign pressure is 50 psig but the normal operating pressure is O psig k=J T » ¥) » « ® 339 at ambient temperatures. The inlet tubing penétrations consist of l/h-in., 30,000-1b autoclave couplings. The outlet tubing penetration is & 6-in. sched-40 tangential pipe nipple which is also welded to the extension of the reactor cell penetration (see ORNL Dwg E-JJ-D-55428). The four electrical conductor penetrations of the tank have Amphenal seals and serve the two d/p cells from the 11 sdlenoid valves. Two l-in. pipe nipples extending from the top of the tank serve as con- tainment for the 1/4-in. tubing lesding from line 522 to the pressure transmitters PRC-5224 and PIA-522B. The d/p cells are accessible by opening one of the flanged ends of the tank and the solenoid valves may be serviced from the other end. 10.10 Piping, Valves, and Appurtenances All piping in the cover-gas system is 304 stainless steel sched 40. The tubing is 304 stainless steel of various diameters and thicknesses. All fittings are welded, with the exception of the threaded valves in the portions of line 500 and 502 that contain untreated helium. The tubing fittings are 30,000-1b autoclave, or equivalent, with the ex- ception that the control valves in the 1/8-in. lines 548 and 549 have Swaglok compression-type fittings. The hand valves are listed in Table 10.1l, the check valves in Table 10.2, and the éontrol valves, inéluding the pressure regulators, in Table 10.3. 340 Table 10.1 Cover Gas System Hand Valves Valve Numbers 500C 503¢C 504 205 51L4B 516 519 541 548 549 572 574 510A 511 500D 500E 500F 500G 503A 503B S00H 510B 200A 5024 5598 5924 593A 594A 539B D92B 593B 594B 576 589¢C 592C 593C 59kC 595C 596C 508¢ 599C 600C 601 606 512 513A 517 S59(A 597B 6054 605B 554 513B S1hA 502B 295A 596A 595B 596B 598B 599B 600B N\ L Specification HVS 1 HVS 1A HVS 1B HVS 2 SSD Description Hoke, TY 440, socket- weld to 1/4-in. OD tubing. Bellows-sealed bonnets. 300 series stainless steel. Same gs HVS 1, but socket- weld for 3/8-in. OD tubing. Same as HVS 1, but socket- weld for 1/4-in. NPS pipe. Hoke, LY 473, socket-weld for 1/2-in. NPS pipe. Bellows- sealed, 300 series SS. Crane, socket-weld to 1/2-in. NPS pipe, bellows=-sealed, carbon steel. Hoke, Y 34k, threaded for 1/4-in. pipe, packed bomnet. Hoke, A 434, forged brass, 1/4-in. NPS male pipe thread, bellows-sealed, Kel-F tip b v 341 Table 10.2 Cover Gas System Check Valves o 500A 510 516A 5194 572A e SThA | | 576 - | 589A n 5924 593A 5964 598 2994 600A 606A 584 511 Valve Numbers 500B 513 516B 5198 572E ST4B ST6B 898 592B 5938 595 596B 5998 600B 6068 549 512 Description Circle Seal, Dwg P705, 3/8-in. Aminco connection, soft seat, spring-loaded, 300 series stain- less steel. Nupro, 2C, with 1/8-in. Swaglok connections, 300 series SS. Nupro, 4C2, modified for autoclave conrections, 300 series SS. Table 10.3. Cover Gas System Control Valves and Regulators Valve Number Spec???fation Cv Size, in. Pog?iion Make Comment PCY 500C 64 - 1/4 Threaded * Fisher Buna-N diaphragm PCV 500G 61 - 3/8 Autoclave * Fisher FCV 500J 18 0.0045 1/2 Autoclave Closed Masoneilan PCV 510A1 18 0.0035 1/2 Autoclave Closed Masoneilan HCV 511A1 18 3.5 1/2 Autoclave Closed Fulton (HRT) HCV 511B1 18 0.077 1/2 Autoclave Closed Masoneilan HCV 511C1 ' 18 0.077 1/2 Autoclave Closed Masoneilan FCV 512A1 18 0.00083 1/2 Autoclave Closed Masoneilan PCV 513A1 18 0.0035 1/2 Autoclave Closed Masoneilan }S HCV 516B1 18 0.0035 1/2 Autoclave Closed Masoneilan PCV 517AL 18 0.077 1/2 Autoclave Closed Masoneilan HCV 519A1 18 0.00083 1/2 Autoclave Closed Masoneilan HCV 572 18 3.5 1/2 Autoclave Closed Fulton (HRT) HCV 574 18 3.5 1/2 Autoclave Closed Fulton (HRT) HCV 576 18 3.5 1/2 Autoclave Closed Fulton (HRT) PCV 605 64 - 1/4 Autoclave * Fisher Buna-N diaphragm ¥Regulator Table 10.3 (continued) “MSRE - ~ Port Fail Valve Mumber gposification Size Blze, in. Position Make Comment HOV 593-Bl Y HCV 593-B2 HCV™"593-B3 |- HOV 593-B4 | HCV 593-B5 HCV 595-B1 HCV 595-B2 o HOV 595-B3 { 139 3/32 in. 1/4% Autoclave Closed Valcor Solenoid-opersted HOV 595-Bh HOV 595-B5 HCV 599-B1 HOV 599-B2 HOV 599-B3 HCV 599-Bl HCV 599-B5 KoV 606 ) 344 11. IEAK DETECTOR SYSTEM » A leask detector system is used to monitor all flanges in the MSRE system which could permit the escape of radiocactive materials. Joints in lines containing lubricants or coolants important to the operation and safety of the reactor are also leak detected. In addition, all flanges which must be maintained by remotely operated tooling are pro- vided with leak-detected type Joints to serve as an indication of satis- factory :;:'eeu!.'sem.bly.ll‘5 There are about 100 leak-detected flanges in the * systemn, The leak detector system operates on the principle of maintaining an over-pressure of 100 psig of helium at all Joints.* In event of a leak in the process system, helium will flow into the affected system. The resulting loss in pressure at the leak detector system supply headers actuates an alarm system. Each of the 60 or more leak detector lines is provided with a hand valve at the header to permit isolation of the line to determine the location of the leaking Joint. 11.1 Iayout and General Description In brief, the leak detector system consists of eight manifolds, or heeders, mounted in a leak detector station cabinet, 2-ft x h-ft x 6-1/2 - ft, located on the south side of the transmitter room. (This room is at the 840-ft elevation, east of the drain tank cell and north of the reactor cell. See Fig. 4.4.) The headers are connected to the helium supply from the cover-gas system and to the lesk detector lines leeding . to each flange. Ieakage is detected by header pressure drop and measured by the rate at which the pressure in the header drops as compared to an equivalent tank volume (500 cec). This arrangement partially compensates for pressure changes in the system due to ambient temperature varistions in the transmitter room. *By definition, if a continuous inflow of helium is required to & part of the system, it is termed a "buffer" flow rather than leak de- LEJ tection. 345 The lesk detector lines leading to the reactor, drain tank, and fuel processing cells, pass through the floor beneath the leak detector system cabinet and are routed to the cell wall penetrations in "Iay-In- Ducts." The general location of the lines is shown in Fig. 1l.1l. The leak detector lines to the coolant cell and vent house are run through conduit around the reactor cell to the special equipment room; from here to the point of application they are mounted on "Unistrut." The leak detector tubing inside the reactor and drain tank cells is either sup-~ ported by "lLay-In-Ducts" or mounted on "Unistrut." Figure 11.2 shows a typical lesk-detected joint. The leak detection arrangement as applied to a freeze flange is shown in Fig. 5.29. The oc- tagonal O-ring type gasket is drilled to permit transmission of the helium gas pressure to all four of the sealing surfaces. On some lines, one leak detector is connected in series to serve two or more sets of flanges. Where valves have leak-detected joints, both sets of the valve flanges are served with one leak detector line, see Fig. 11.3. Where both flange faces in a pair must be removable for maintenance reasons, such as on the pumps, the freeze flanges, etc., it is necessary that the leak detector lines have disconnects which can be remotely ma- nipulated. These disconnects are described in Section 11.6, following, The leak detector system is constructed of %0k stainless steel. The tubing is 1/4-in. OD x 0.083-in., wall thickness and all piping is sched 40. All valves are bellows sealed, as described in Section 11.5. If it is assumed that the leak rate of 1077 cc/sec determined in the development of the freeze flanges (pp 41-45 Ref 38) is representative of the average leak rate of the 100 flanges in the MSRE system, the total leakage is in the order of 6 cc/min. This amounts to about 75 cc/min per header. Taking the average volume of & header and its connected lines to be about 1,000 cc, this loss of helium smounts to a pressure loss of gbout 0.66 psi/hr. The minimum full range of the differential-pressure cell used to indicate the pressure difference between the header and the volume tank is 5 in., of water, or about 0,18 psi. A change in the dif- ferential pressure of 0.05 psi per hour (28% of full range) indicates a leak rete of about 0.04 cc/min (6.67 x 107" cc/sec). Unclassified ORNL DWG 64-8832 & Leak L - el by cmm [ B 7% \‘ l_— Trans. Room Detector — 1 System Control Panel Spare Cell J ' b cupllh SEAkinb ‘I N J r | ™ — ' 1 ! Fuel Drain Tank Cell Proc. Cell 7. Flgure 11.1. General Routing of Leek Detector Lines ove 347 & Unclassified ORNL IWG 64-8833 ] o\ /s s LEAK DETECTOR / SEALING SURFACES LINE FROM LEAK - DETECTOR STATION L— O-RING GASKET .S S SN NAM SN SANSSNASNANN * ARNN S ’ 4 \\\\\\\\) 4 / LEAK DETECTOR LINE TO NEXT FLANGE OR MAY BE CAPPED OFF SEALING SURFACES N FLANGES Fig. 11.2. Schematic Diagram of Leok-Detected Flange Closure. 348 ANY LINE REQUIRING LEAK DETECTOR SERVICE REACTOR COMPONENT Unclassified ORNL TWG 64-8834 REMOTE DISCONNECT FLANGE '———_ T D TN I S LEAK DETECTOR Lme-/- 1 Fig. 11.3. Method of Utilizing One Leak Two Flanges in Series. PERMANENTLY INSTALLED PIPE FROM LEAK — == =g =} DE TECTOR STATION Detector Line to Serve £ u & 349 11l.2 Flowsheet The flowsheet for the leak detector system is shown in Fig. 11l.k (ORNL drswing D-AA-A-40890). Helium is supplied at 250 psig through 1/2-in. Line 51k from the cover-gas system (see Section 10.3). This line reduces to 1/h-in, tubing inside the leak detector system cebinet. The helium is supplied through valves V-514-B, CV-51k, and PCV-51Y4, the latter regulating the pressure to 100 psig. After passing & connection through which helium can be supplied in an emergency, the flow is distributed to each of the eight headers. The distribution line, ILine 514, contains a high-low pressure alarm switch set for the 90 to 110 psig range. Each helium supply to a header is provided with an isolation valve. Each header serves as a valve manifold for ten 1/k-in, leak detector lines, which are grouped by appliéation‘and‘1ocation; as shown in Table 11.1. Iines %10 through 41h4 on header 401 serve the reactor cell freeze flanges. ILines 415 through 419 are spare leak detector lines leading into the reactor cell. All ten.of these lines have one hand valve at the header and are provided with disconnect couplings inside the réactor cell, ' Header 402 serves the reactor cell helium lines. Each of these leak detector lines, 420 through 429, has two hand valves in series, with the inmer, or "B" valve, being used to prevent backflow from the cell in event maintenance is required on the operational valve, "A." Each of these leak detector lines is connected to two pairs of flanges in series. Thére are no spare lines on this header. . Header 403 monitors reactor cell water lines. Ieak detector ILines 430 through 43k are connected to half-flanges in the thermal shield water piping. (These half-flanges are installed where the welded piping system is likely to be cut for maintenance procedures and later rejoined by spool pieces with bolted mechanical joints.) ILines U435 through 439 serve other water piping flanges. Each of these ten lines has one hand valve at the leak detector system header. | | | Header 4Ok serves miscellaneous reactor cell flanges, such as the oil piping flanges (Leak Detector Lines 440, 441, and L442), and the pump A Mottt At g b o g 350 OEICAPTION QMME, S, ) O 9 © 6 § Pl 4014 M o V40Q3A v402a v @ 2‘6‘0"” V40 V4O8A @ & @ 5% G G- , | va038| va028| V4018 — TO FFI00 Va0o6B | v4058| v4O4s LINE TO3 FLANGES voss | Vveore COOLANT PUMP LOWER FLANGE —-@—"63_-.. To FFIOI —-@-—%—-— LINE 704 FLANGES COOLANT PUMP UPPER FLANGE YOR0eee g}—"@"%“""‘u 1o Frioz SF—CE‘—N—MI LINE 708 FLANGES PCv 228 z 738 il vai3 TO FF2O0 g-—-@:b—-wf::‘w‘ R UINE 389 FLANGES PCV 522 * i o VA44A _~vaaal 748 - wl L ED> Y 10 Fr200 —@RD—{AT- FUEL PUMP LOWER FLANGE FO! ACCESS FLANGE u 3 VAABA _—va4SB 738 vame V3140 ]F & 'ro FF200 FUTURE NM FUEL PUMP UPPER FLANGE FD2 ACCESS FLANGE ewincency C—Pg— . vaig o _@sz:‘éu NECK AND e ccEss FLANGE CYLINDER SUPRLY " L CONMECTION vsiec X 3 To FF201 FUTURE e SRAPHITE SAMPLER FLANGES 7 u VARV s @D "‘N"‘fil‘}u‘ he3 FLANGES TO FES2I FLANGES (f:)._ = & a4sa ,—VAAEE | § @—':':—o SPARE TO RC d—@—vm—lfi:.ucv 423 & v523 SPARE TO CC 198, 3 wie i@ t— ance 1o Hovsss @; €L (@D —Pg—e SPARE TO RC L TG LINE 918 FLANGES 3 [ ‘ , ) | | NOTES: 2 ~ I_EQUIPMENT SHOWN TO BE LOCATED IN THE TRANSMITTER ROOM. VA20A V4208 @ED—EAR= Line. ie FLanees e ey 692 2-LINE 54 (AFTER REOUCER) ANO LINES 400-40T ARE 2%1PS-SS PIPE. vi2 v WITH INSERT TO REDUCE VOLUME. A2 —g—= SPARE TO RC : vag vpaza _—w228 ° @B | L HCV 694 3_LINES 410-489 ARE ] QD 83 MIL WALL $3 TUGNG. Zcvsia —-@-—Dfl-mc-uu: 822 FLANGES w eor ) V23A 4238 s —@8D)—Pg—a SHRE TO ESA "'“—@_M"“ 324 FLANGES - . S_APPROKIGATELY 40 ADOITIONAL W-J, FLANGES WILL BE PROVIOED s VAZAA 4248 ® @S P SMRE TOESA WITH MEANS FOR LOCAL LEAK CHEamMG. | V5148 3 -——@-——NNC LINE 530 FLANGES @ e VA2IA _ V4258 < vag4 SOOUSLE VALKES ARE PROVIOED W LINES TO FLANGES OCONTANGNG et S—@ZD—AC LINE 392 FLANGES 2 W A8 SPARE ACTIVITY, THE DOWNSTREAM VALVE (WY WALL BE LEFT OPEN ENCEPT HELIUM " R w v On 2" waLve. Duce ViZEA _~vazes vas DURING MAINTENANCE sureLy EL@—M LINE 596 FLANGES G X 2| @TD g soane w27h VA28 VASTA V4378 & DK UINE 593 FLaNGES S| —G@ED—AF= LiNe 572 FLaNGE 2l Ve e } %0 ss. e vAZeA V4288 - v438A V4588 g o (18Dt LINE 599 FLANGES : D000 LINE 574 FLANGE S vea? - VAZSA V4298 : e O (A8 D—P—— SPARE B (@2 LINE 600 FLANGES - 5 LINE 576 FLANGE o vane : z Yl @B —{}——s NeF TRAP INLET FLANGES 3 ; ' - V489 vaso « veso | NoF TRAP EXIT FLANGE ~@D—IX LINES 844 F,G, 8454, ©FLANGES . LINE 804 FLANGES ‘ | THIS DRAWING REFLECTS V43| 2 vae) : ] LINE B44H, 2 FLANGES » LINE 804 FLANGES : AS BUILY vas2 e vas2 » LINE 8448,D,E, 8 FLANGES @ D—LX—+= LINE 808 FLANGES CHANGES ad vas vas) —oan 3 ; INE 844C, 2 FLANGES :r@—m—— LINE 807 FLANGES vare _2-23-64 vasse r w vass ‘ & LINE 830 FLANGLS b LINE 636 FLANGES ;, % vass vass ! i_@—m-.. LINE 031 FLANBES - (445 [x LINE 837 FLANGES ; T‘ms:fi :::::: mfl; 4 u - vass : COQLANT muuum 3 3 o HINE 038 FLANGE O —@D—tt— sranc 10 0TC ‘ COVER GA3 _sYsvEw it 9 va3? > vae? : OFF _GAG SYSTEM & CONTAMMENT VENT Iaksssid [ —@D—Dd—e- NE 846 FLANSE . sPaRe 70 OTC s [FUEL ORAIN_TANK SYSTEM | e prsnae: o vass ‘ ‘ - 5 "t e 840 FLANSE =@ srane To OTC | CoociT svTEw s v @ LINE 841 FLANGE <1 $PARE TO OTC l o — Y™ ' - ———— -. ' i) | PROCESS FLOW SHEET . L ‘:'d."..u:a";:-h M.S.R.E. ) i MACHINE PREIN TUCINGARGNS LRSS W GRANS SNAAN O MIOSE MATIONAL LABORATORY ] | : L. Pt bl e g sommdume S — 8 | SEEDCN 2930 A A 2l onry AA Shl-is TETIN R e | m m m COMPANY A A l.:nhvnuhnb . VIR OF VRN CARENE CONPORCINN A | see pew zan Jax > -h--l-:_. P I— . tm NCAmONS it [avo [awo ARV . n ez ls. 3004 15/7%3 : 1 et i P ! , j FIGURE L& L — v 351 Table 11.1. Leak Detector System Headers Connected Iesk Detector Lines Header No. General Service Lol Reactor cell freeze flanges Nos. 410 - 419 402 Reactor cell gas lines Nos. 420 - k29 403 Reactor cell water lines Nos. 430 - 439 Loy Miscellaneous reactor cell flanges Nos. 440 - 4h9 405 Drain tank cell gas lines Nos. 450 - L59 Lo6 Drain tank cell steam and water lines Nos. L60 - 469 o1 Miscellaneous Nos. 470 - k79 408 Fuel processing cell Nos. 480 - 489 352 and reactor neck flanges (Lines 443 through L46). Lines 443 through LkL6 have two valves in series at the header. Lines L4k through 449 have dis- connect couplings inside the cell. ILines 447, 448, and 449 are spare lines for the reactor cell. Header h05 is used to monitor gas piping flanges in the drain tank cell. Iine U450 is & spare lesk detector line to this cell, Lines 451 through 459 have two valves in series at the header. Header 406 serves the drain tank cell steam and water piping flanges. Lines 460 through 465 are used for this purpose and the remsining four lines serve as spares for the drain tank cell. Header 407 is used for flanges classified as miscellaneous. These include the coolant salt circulating pump upper and lower flanges (Ieak Detector Iines 470 and 471), and flanges at the gas control valves in the coolant cell and in the vent house (leak Detector Lines 472, 473, and 479). Lines 474 through 476 monitor flanges on the fuel drain tanks. These three lines have disconnects inside the drain tank cell. Lines 473 through 476 have two valves in series at the header. Iine 478 is a spare line to the coolant cell. Header U408 monitors flanges in the fuel processing cell, Lines 480 and 481 serve flanges on the control valves HCV-692 and HCV-69L4. Iines 482 and 483 are installed spares to the electrical service area. Lines L84 and 489 are spares. ) All eight of the above-mentioned headers are connected through hand valves to Line 400, which leads to the 500-cc tank through a normslly closed block valve, V-h0O., A differential-pressure cell, PAT-400, con- nected between this tank and Line U400, senses small changes in the header pressure compared to the tank pressure. In addition, Line 400 has a high end low pressure switch which annunciates an alarm on the msin control panel in event of deviation from the 90 to 110 psig set range. 11.3 Headers Each header consists of a 19-1/2-in. long section of 1-1/2-in. sched 40, 204 stainless steel pipe, capped at each end (see ORNL drawing D-JJ-D-55403)., A 1-1/k-in.-diam stainless steel rod is enclosed inside 353 each header to reduce the free volume. To assure that this inserted rod does not block any of the leak detector openings, three equally spaced wires, 0.040-in. diam, are tack welded the length of the insert to space it centrally within the header pipe. The free volume of any branch was limited so that the response time for a leak of 1 cc/min would not be less than 0.5 psi/hr (p 2 Ref 145). There are thirteen 1/4-in. OD x 0.083-in. wall thickness tubes welded to each header. To these are connected the ten leak detector lines, the helium supply from Line 514, the connection to Line 400 and the tank, and a line to a pressure gage. 11.4 Valves Each tubing line contains a miniature, bellows-sealed hand valve (Hoke, Type 480). These valves were salvaged from the Homogeneous Reactor Test (HRE-2) and were completely inspected, reconditioned and tested. Leak detector lines which monitor flanges in direct contact with radio- active gases have two of these valves installed in series at the header so that the inner valve can be closed to isolate the system while the operational valve is being repaired. 11.5 Disconnects In the cases where flanges inside the reactor cell must have both faces removed to effect a maintenance procedure, the associated leak de- tector lines must have nearby disconnects which can be operated by remote tooling. These couplings must he as free as possible from any leakage. The design selected for use in the MSRE, as shown in Fig. 11,5, was developed in the ORNL Chemical Technology Division and in the Reactor Di- vision.146 The sealing principle is based on elastic deformation of a "polished metal cone when inserted in a polished seat. The block on which the male cone is mounted and the block containing the matching seat are of the proper dimensions to make contact to prevent the cone from being Jjemmed into the seat and deformed plastically. The two blocks are held together by a simple but positive yoke assembly. The single bolt on this yoke facilitates operation by remotely handled tools. 354 Uncltassified CRNL DWG 64-8835 = Pipe or tubing bore, + 0.0025 in. = Major male diemeter boss before taper, +0.000 - 0.001 in. = Major femsle dismeter before rounding entrance edge’ + Ole - 0-000 1no = 22°, +0° - 1/2°, included angle tapered cone. = 23.1/2°, + 1/2° - 0°, included angle tapered hole. A B c D E 1/2-11;. %x l=3/4ein. Bolt —. .“i _ . 1-1/8-in. Dia (Peened to Bolt) —_——t - - - { ~ o3 | & 7/ A P— . ) A%// LRI I LIS LI OO LA LIS ~ Lk N _ . ///‘/ | I= 3/8a. I-_ _‘I__l—‘ 3/8-tn. I-_ le/lzl in. square L 2.1/16-1n. TR B AR J Section AA A 0.250 0.375 0.500 0.625 0.750 B 0.398 0.533 0.668 0.803 0.938 C 0.400 0.535 0.670 0.805 0.935 Contact 0.035 0.040 0.045 0.050 0.055 Well Figure 11.5. Leek Detector System Block Disconnects with Yoke. > 355 Tests made during development of the coupling indicate that a leak rate of less than 10'6 cc/sec (STP) can be expected even after the joint has been broken and remade thirty times or more. These tests were made at room temperature.lh? At temperatures of a few hundred degrees (OF), it was indicated that the joint might be manipulated at least twenty times before the leak rate was increased. It is anticipated that all MSRE dise connects will operate at the cell ambient temperature of about 150°F. A light coating of an alcohol-graphite mixture is recommended for the cone before the joints are made. | 11.6 Iocal leak Detectors The flanges in the fuel and coolant pump lubricating oil systems are provided with local lesk detector connections to.which helium gas cylinders can be connected when a legak is suspected. This leak detection arrangement is not connected to the reactor leak detector system. Each of the lube 0il packages contains nine local lesk check points, see the lubricating oil flowsheet, Fig. 5.25 (ORNL drawing D-AA-A-40885). 356 12. OFF-GAS DISPOSAL SYSTEM The off-gas facility provides for the safe disposal of radioactive gases discharged from the MSRE. The system handles three different types of gas flow: (1) the continuous discharge of helium containing highly radioactive fission-product gases swept from the fuel salt circulating pump bowl; (2) intermittent, relatively large flows of helium containing, at times, significant amounts of radioactive gases and particulates, such as that discharged during salt transfer operations; and (3) flows of up to 100 cfm of very low activity cell atmosphere gas (5% 0,, 95% N2), which is ejected either intermittently or continuously to maintain the reactor and drain tank cells at sub-atmospheric pressure. ' The unstable isotopes of iodine and bromine resulting from the fis- sioning of the 235U in the fuel salt largely remain in the salt solution as complex halides until they decay to elemental xenon and krypton. Since it is desirable to remove the l35.Xe from the fuel salt circulating system because of its high cross section for capture of neutrons (e = 3.5 x 10~ b}, it and other fission-product gases are swept from the fuel pump bowl by a helium gas flow of about L liters/min (0.15 cfm at STP). When operating at the 10-Mw reactor power level, the activity of this stream leaving the pump is about 280 curies/sec.llL8 The gases are held in the piping for about two hours for the short- lived isotopes to decay. They then pass into a water-cooled bed of acti- vated charcoal. The adsorbed xenon is retained in the bed for at least 90 days and the krypton is held for 7-1/2 days or more. During this time, essentially all the fission-product gases decay to stable elements, some of which are solids that remain in the charcoal. Only three radioactive isotopes, 85Kr, l3lmXe and 133Xe, exist in any significant amounts in the helium carrier gas leaving the chafcoal bed. (See Table 12.1) Of these, the 85Kr with its half-life of 10.27 years, is of the greater concern. The maximum discharge rate of this isotope is 5 curies per day. The effluent from the charcoal bed is monitored for activity before passing through roughing filters and then absolute filters having an ef- ficiency of 99.9% for particles greater than 3 microns in size. The gas e 357 . -‘Table 12.1 Design Data Off-Gas Disposal System Charcoal Adsorber Beds - Off-gas charcoal beds (four sections) | Design flow (two sections), cfm Design temperature, °F Design pressure, psig Xenon holdup (minimum for two sections), days - Heat load, (two sections) kw Charcoal bulk volume, (two sections) £t Charcoal weight, (two sections) 1lbs Length (each section), 1-1/2 in. pipe, ft 3 in. pipe, ft 6 in. pipe, £t Over-all pressure drop, psi Auxiliary charcoal bed Design flow, cfm Design temperature, °p Design pressure, psig Charcoal bulk volume, ft3 Charcoal weight, 1lbs Length, 6 in. pipe, ft 70ver-all pressure drop, psi . fiCapaclty at breakthrough ft3, stp Stack Fans (two) Hbrsepower Capacity at 11.5 in. water, cfim “Design-flow rate,;" cfm Exit roughing filter Type Ares, ft2 o Depth, in. 0.15 5883 L 1450 80 8l 1.5 85 16 530 1.25 14k 0 21,000 20,000 Fiberglass, deep bed pocket 350 for each of 3 banks 1/2 of 3.25 micron fiber disa 1/2 of 1.25 micron fiber dia 358 Table 12.1 (Continued) Efficiency Initial pressure drop, in. of water Absolute filter Type Ares, ft2 Depth, in. Efficiency Initial pressure drop, in. of water Stack Height, ft Diameter, ft Activities leaving stack, pc/cc 83y, (Half-life 114 m) OOme. w v y36m 85%r "o 1027y BBy "o o7 h 88Rb " 17.8 m Bloge v n 1004 3mge v v 234 133 noon 507 g Expected dilution to maximum ground concentration 90-95% by NBS test a with atmospheric dust 0.6 @20 ft/min Fiberglass, high efficiency 2k for each of 3 banks 11-1/2 99.97% > 0.3 micron 1.05@280 ft/min 100 4 at bottom, tapering to 3 at 25 ft elev. 3 for top 75 ft 7.0 x 107 1.0 x 10'8 6.2 x 10°° 1.3 x 10712 . 1.2 x 10—11 1.0 x 107° . 6.3 x 10*15 ~ 6.1 x 1071 f mlOlL | (i 359 is massively diluted with atmospheric air and discharged from the top of a 100~ft-high stack about 110 £t south of Building 7503. The concentration of O%kr in the stack discharge is a maximum of 6.2 x 10 ~ microcuries/cc, which is within the accepted tolerance level. The ground level concen- tration is estimated to be less than this by a factor that may be as great as 10,000. 12.1 Iayout and General Description In addition to the fuel pump bowl, other equipment vented to the off- gas system includes: the three fuel salt drain tanks in the drain tank cell, the fuel pump shaft seal seepage in the reactor cell, the graphite sampler, also in the reactor cell, the sampler-enricher in the high-bay area, the coolant salt pump seal and pump bowl in the coolant cell, the two lubricating oil system packages in the service tunnel area, the coolant salt drain tank in the coolant drain cell, and the reactor and drain tank containment cells themselves. Design data for the off-gas system are summarized in Table 12.1. The schematic diagram in Fig. 12.1 and the following brief outline of the course of the fuel circulating pump bowl off-gas line, and the ‘equipment associated with it, will serve as a general description of the off-gas system. The gases leave the bowl through a 1/2-in. stainless steel pipe, line 522. The pipe size changes to 4 in. at the disconnect flange and partially circles the inside wall of the containment vessel. The total length of Y-in. pipe is about 68 ft, which includes a serpen- tine section, and provides a holdup volume of about 6 £3. This is suf- ficient for about one hour's delay for the decay of fission-product isotopes. A 4-ft horizontal length of the 4-in. liné 522 is enclosed in a 6-in. sched lohpipe at the 831-ft elevation and 400-600 scfm containment atmosphere‘gas (95%TN2, D% 02) is introduced through line 960 into the annular space to help cool the off-gas. The off-gas line continues through the reactor cell wall penetration as l/2—in. pipe and across the coolant salt areas as l/h-in. pipe encased in a 3/4-in. pipe, which, in turn, is surrounded by about 4 in. of lead shielding. Line 522 then passes through valves in a pressure~tight HELIUM ____ SUPPLY HELIUM SUPPLY T RESTRICTOR FUEL PUMP OVERFLOW TANK VOLUME HOLDUP LOOP VOLUME L L o Lj % 5 TYPICAL ORAIN TANK HOLDUP LOOP BUILDING VENT REACTOR CELL | HEADER — T — — ——— — — COMPONENT COOLING . /_)_ ABSOLUTE L""["J SYSTEM BLOWER 7 FILTER 30 in. ] - 21,000 c¢fm FAN — ACTIVITY' COOLANT , {MONITOR PUMP I E E ] I % COOLANT SAL;_I'Al')qI}AIN #DRAINS REACTOR ON HIGH ACTIVITY Fig. 12.1. Schematic Diagram of Off-Gas System. UNCLASSIFIED ORNL DWG. 64-394R STACK ACTIVITY MONITOR O9¢ 361 instrument box located in the lower portion of the vent house. From here it continues as a 1/4-in. pipe in an underground shielded duct to an under- ground valve box and then to the charcoal bed cell. This cell is located below grade just south of the vent house, as shown in Fig. 3.2. The cell was an existing facility consisting of a 10-ft-diam x 22.7-ft-deep re- inforced concrete pit with a 3-ft thick removable concrete cover. The off-gas pipe, line 522, connects to three vertical 20-ft high U-tubes of 3~in. pipe which provide about 7 ft3 of holdup volume and an additional one hour of residence time. The gas then enters one of two activated charcoal beds, the other bed acting as a spare. Each of the two beds consist of two vertical sections of U-tubes with the pipe size varying from 1-1/2 in. to 6 in., and each containing about 22 £65 of activated charcoal. The charcoal bed cell is filled with water and the beds are cooled by the water flow through the cell. The effluent from the charcoal beds, which consists primarily of the helium carrier gas*, flows through an underground 1/2-in. pipe to an under- ground valve box and then to a filter pit located about 75 ft south of Building 7503. (See Fig. 9 and Section 4.7) The reinforced concrete filter pit is about 21 x 29 ft, varies from 5-1/2 ft to 7-1/2 ft in depth, and is covered by 1-1/2-ft-thick concrete roof plugs. The off-gas mixes with about 21,000 cfm of air drawn thrcugh the filters by a 50-hp fan (an identical fan is installed as a spare) and, thus massively diluted, is discharged from a 3-ft-diam x 100-ft-high steel stack located about 110 ft south of Building T7503. | Off-gas vented from other points in the MSRE system is handled similarlytand utilizes much of the same equipment. The gas discharged from the fuel drain tenks flows through a 1/2-in. pipe crossing the coolant :salt ares to the aforementioned instrument box at the vent house, and to an auxiliary charcosl bed located in the charcoal bed cell. The ViSOtopesrin this stream have already decayed to reduce the heat release rate sufficiently to permit use of larger diameter pipe for this charcoal ¥There are no provisions in the MSRE for processing and reuse of helium. Consideration has been given to adding this facility later in the experiment. 362 bed. Two vertical U-tube sections of 6-in. pipe contain about 16 £t3 of activated charcogl. The outflow of this bed Jjoins the flow from the main charcoal beds, and other off-gas streams, and is monitored, filtered and diluted before discharge up the off-gas stack to the atmosphere. Cover gas vented from the coolant salt circulating pump bowl and from the coolant salt drain tank bypasses the charcoal beds in the off- gas system, but is monitored and filtered before discharge. The cell atmosphere gas is evacuated from the reactor containment vessel and the drain tank cell by blowers located in the special equip- ment room. The blower discharge, after passing through a gas cooler, is for the most part, returned to the cells to cool specific items of equip- ment, such as the upper portion of the fuel circulating pump bowl. - (The component cooling system is described in Section 16.) A small side stream of the blower discharge is vented through the off-gas system to atmosphere to maintain the cells below atmospheric pressure. This 1-1/2-in. line passes through the vent house, where the gas is monitored, and may be sampled when necessary, before being filtered and discharged up the stack. The filters, stack fans, and stack are described in Section 13. 12.2 Flowsheet The off-gas system flowsheet is shown in Fig. 12.2 (ORNL Dwg D-AA-A- 40883). The origin of the lines venting to the off-gas system are, in general, not shown in Fig. 12.2, but on the flowsheets fbr the particular items of equipment involved. ' The off-gas line from the fuel circulating pump bowl, line 522, is 1/2-in. pipe but changes to 4h-in. pipe a short distance from the pump and extends for sbout 68 ft inside the reactor cell to provide a holdup volume of about 6 ft3 and a residence time of about one hour. The line continues as 1/2-in. pipe through the cell wall penetration and across the coolant drain cell as 1/4-in. pipe to an instrument box located in the lower portion of the vent house. In this box the flow passes through a hand valve, V-522-A, & porous filter, and then a pressure control valve, PCV-522. This valve maintains a constant pressure of ~ 5 psig in the pump bowl by throttling the sweep gas discharge. (The flow rate of the DRAIN TA‘N(S FROM FUEL L CAYCH rvaze INSTRUMENT NS 33,( E CHARCOAL voruwe il BED CELL | 'VENT HOUSE even INFILTRATION B8T0 CFM MAX. INLET AIR FILTER HOUSE 16,000 CFM (MAX} FROM CNOLANT & OIL SYSTEM CYLANT DRAIN “ELL CHARCOAL BED CELL {CBC) AUXILIARY CHARCOAL 8ED {ACB) CHARCOAL BED NO. 1A CHARCOAL BED NO. 1B CHARCOAL BED NO.2A CHARCODAL \ BED 5 | I | CHARCOAL BED DATA @ t Od TC C.3 WATER PRESSURE (sC) EQUIPMENT STORAGE CELL (ESC) SFARE CELL M TF NAIN PRACTICE CELL (RMC) DECONTAMINATION N COFT/MIN.EACH DURING MAINTENANCE HIGH BAY AREA (H8) THIS DRAWING REFLECTS AS BUILT CHANGES pare_9-21-64 FUFL FRCCESSING (FPC) . CVSSTA SPECIAL EQUIPMENT (SER ELECTRICAL SERVICE AREAS (esa-n} | | 3 REACTOR LESA-S) CELL (RC) 2.0 PSIG - LEAK FROM WATER ROOW 28" THIO BEMEN 8 THE PROPERTY OF UMON CARBIDE NUCLEAR COMPANY = DIVIBION OF SF 1 STACK FAN NO.1 21,000 CFM AT 10" 1,0 SWITCH FANS ON HIGH PRESSURE SYSTEM WNST. APPLICATINN DIARRAM FUEL DRAIN TANK SYSTEM COOLANT SY dynamic absorption tests. Each section has a maximum flow rate of 2.1 liters/min. The centerline temperatures calculated for several flow rates are shown in Fig. 12.4. The temperatures are measured by a thermo- couple at the inlet of each different pipe size in each section. The maximum pressure drop is estimated to be 1.5 psi. 12.4.2 Auxiliary Charcoal Bed Since the auxiliary charcoal bed is used intermittently, there is enough time between periods of use for fission-products to decay to levels where a breakthrough of activity from the bed is highly im- p]:'oba,ble.m8 Further, the specific activity of the gas passing through the bed is low enough to make heat release in the bed only a minor consideration. 3 or gas (STP). The The auxiliary bed is designed to contain 140 ft maximum design flow rate is 1 cfm (STP). The bed consists of two vertical U-tube sections of 6-in. sched 10, 30k stainless steel pipe. The legs are about 19.21 ft long connected by short-radius 180° bends at the bottom and with 1/2-in. pipé_connect— ing the capped tops in series. The total amount of charcoal in both *Based on a bulk density for the charcoal of 0.53 gr/ecc. ot 375 Unclgssified ORNL DWG 64-8839 400 300 T e o o 3 £ 200 i : :5 100 J*””” 0 1 2 3 L Inside Pipe Diemeter, In. Power = 10 Mw Bypass Stream Flow = 50 gpm Sweep Gas Flow = 4.2 liters/min (total) 1.05 liters/min (bed) Pre-bed Holdup = 2 hrs Figure 12.6. Maximum Estimated Tempersture in First Section of Charcoal Bed vs Pipe Diameter. 376 sections is 585 1bs and is of the type used in the main charcoal beds. A 3-in. thickness of stainless steel wool at the top of the leg pre- vents movement of the charcoal. The inlet temperature to each section is measured by a thermocouple in a well on the centerline of the pipe. Fabrication details are shown on ORNL Dwg E-JJ-B-41519 through 41524. 12.5 Piping, Valves and Filters 12.5.1 Piping All piping inside the reactor and drain tank cells is seamless 304 stainless steel, sched 40. In most cases this pipe wall thickness was not governed by internal pressure considerations but was selected to pro- vide resistance to mechanical damage during installation and maintenance of the reactor. The piping outside the containment areas is sched LO carbon steel. PFittings used with the stainless steel piping are butt- welded. Some valves, however, are socket-welded, or flanged, as may be noted in the off-gas system valve tabulations, Tables 12.3, 12.4, and 12.5. The carbon steel piping is either screwed or welded, depending upon the accessibility for inspection and maintenance and upon the seriousness of the situation developing from a possible leak. The main off-gas pipe, line 522, and the auxiliary off-gas pipe, line 561, are each contained within another pipe in the run between the containment vessel wall and the valve box in the vent house. Both inner and outer pipes are seamless 304 stainless steel, sched 40, and all Joints are butt-welded and X-ray inspected. The annular space is pres- sure-tight, sealed at the reactor cell wall and open to the instrument box atmosphere. The slight vacuum in the box produced by the suction of the stack fans provides assurance that any out-leakage of radioactive gases will be carried to the filters and the off-gas stack. The monitors on the lines leading to the filters would detect any radioactivity escaping through such leaks. 12.5.2 Valves The air-operated valves in the off-gas system are of the flanged type. All others inside the containment vesgsel were welded into the 37 piping either by butt or socket-type Wélds. The valves in the off-gas system are listed in Tables 12.3, 12.4, and 12.5. Hand valves in piping which must be shielded, such as those in the underground valve box at the charcoal bed cell, have special extension handles, as shown on ORNL Dwg D-JJ-A-56255. 12.5.3 Filters 12.5.3.1 Porous Metal Filter in Line 522. - A filter is provided in line 522 upstream of the control valve, PCV-522, to protect it from possible damage or plugging. The filter housing is a section of l-l/E-in. 304 stainless steel pipe about 20 in. long with a8 cap welded on the bottom and a ring-joint flange'at the top, as shown in Fig. 12.7. The filter element is a fluted porous metal cylinder 1-1/32-in.-diam x 17-in. long. The pore.diameter is 40 microns and the surface area is about 6 in.2/in. of length. The filter element is screwed to a 1/2-in. coupling welded to the 1-1/2-in. x 1/2-in. reducing flange which effects the top closure. The 1/2-in. inlet pipe, line 522, enters the side of the filter housing. The 1/2-in. outlet pipe connects the top flange to the control valve HCV-522. The pressure loss due to flow through the filter is negligible at the maximum design flow rate of 4.2 liters/min. 12.5.3.2 Porous Metal Filters in Lines 524, 526, 528 and 569. - The filters in lines 524 and 526 are upstream of capillary flow restrictors to provide protection against plugging. The filter in line 528 is up- stream of the control valve, HCV-528. Line 569 leads to a sampling station and the filter is installed upstream of the sampling valve, V-569 4 : ! 1 i 180 CPM— =TO OFF GAS ' L FILTERS PIT_PUMP o . . . {sze - SHP ' _ I ‘ : ; ‘ ' : ‘ ' ‘ I n) [ : ) ) o o e l . . it (m PrasaZvans r :'?— ! o : ‘ o # . o FROM wesT 1-40-38 ‘ ’ ‘ o e -0 ExsTENT TUNNEL (N.C.) LL ACCESS - DOOR - ' - : . SUMP W COOLANT ) I €T 2- 40- 88—, — D] v3oz o DRAIN CELL - . 9D 302 : ' @) S - (g) @ @ TEST VALVES i l — ] 2-40-88 ) y ;' A I & . fa by §f - _ S—IO-SS—/ I , Va0 « a L@_ of g ) fi\l TO CENTRAL FUEL PROCESSING -40-s8 3058 ?ngn CELL Sump ' Y/ 14 vae Cvae S.B e . ‘9 i (30D 5’) WASTE PUMP ¢ L TR (948 SPARE WASTE PUMP DATA . CELL SUMP I ” LIQUID WASTE STORAGE TANK i . CAPACITY 140 GPM (W) | i A HEAD 80 VENT TO DUCT 340 l” I i V3088 V30T ' EQUIPMENT STORAOE | A > g cewt EQUIPMENT STORAGE i A yya 202 CELL Sump £-10-m | THIS DRAWING REFLECTS 0 \& WASTE FILTER 312 &fimc .?(E:firuaein baureRrial 302 STAINLESS STEEL } | AS BUILT J. W) ‘ :g:;gmgl:'gfi , SIZE iwe s e e J | i FUEL,_ PROGESSING SYSTEM jpAs-a-40887 RO M {FuEL PROCESSING cEL CAPACITY woooear. || CHANGES : COOLING WAaTER SYSTEM [oAa-a-s088s » | oaTE __9-23-64 ‘ 2- 40-55 LIAD WASTE SYSTEM INST. APPLICATION DiA. |D-An-B-40309 } 4 i 7 Fuel, SYSTEM D-Af-A-e0080 | . 3% DRANG TAWK SYSTEM, DAs-A-a00e2 | . 24 40-35— ' OFF GAS SYSTEM & CONTANMENT VENT. |0-As-A-40883 i LIQUID WASTE CELL . = REPENENCE DRAWINGS owe. no. . I “ pw " fi:fl | S e e OAR RIDAR NATIONAL LABORATORY vas zcvsm }-40 -~ L D - ?62 Q"'.V%r e i —— S S— LIQUID WASTE SYSTEM t - - ; U Y PR ” ‘ % 2881 SEE DCN 2881 AL /ft 61 wninh x ‘ M.S.R.E. ‘ £anr SEE DO 249 i PCIPE Rutls ¥, RB¢ . iy | ScALE: wowe o8 43310 | [o-As-a-40088-c A » c B 2 - ! ' THIS DEHIAN I THE PROPRATY OF LNIGN CARBIDE NUCLEAA COMPAMY = DIVISION OF UNICH CARBIDN CORPORATION U4t srrum rsmr v - ‘ : FIGURE 4.1 __| 400 Steam-actuated ejectors in the sumps of the liquid waste cell, the equipment storage cell, the fuel processing cell, and the spare cell, discharge into the liquid waste tank through lines 316, 318,‘320 and 322, respectively. These are all 3/h-in. sched 40 stainless steel pipes. The steam ejectors are supplied with 60-psig saturated steam through lines 315,’317, 321 and 319, respectively. Each of the steam supply lines con- tains a check valve to serve as a vacuum breaker. ‘ The steam ejector which empties the caustic scrubber tank in the fuel processing cell, is supplied with 60-psig steam through line 312. The | - jet discharges through a 3/4-in. sched 4O monel pipe, line 314, to the top of the waste storage tank. | I | _ The sumps in the reactor and drain tank cells are equipped with liquid level indication through use of bubbler' lines 965 and 966, respectively. These 1/2-in. sched 40 stainless steel lines are supplied with nitrogen for purging oxygen from the cells and contain rotameters of up to 0.31 1/min 'capacity. The bubbler level indication is in addition to the level alarm switches which are providéd'on all sumps. = - L The above-mentioned sumps in the reactor and drain tank cell are emptied by ejectors actuated by service air. The 100-psig supply air is passed through a pressure regulator, PCV-332, and distributed to the drain tank cell through line 342 and to the reactor cell through line 332. Both of these lines are 3/4-in, sched LO stainless steel and have hand-operated valves and check vaives to prevent back flow from the cells. The reactor cell jet discharges info line 333 and the drain tank cell jet into line - ' 343, both of which are 3/4-in. sched 40 stainless steel pipe leading to the liquid waste storage tank. Before entering the storage tank, each line is provided with two flow-control valves in series, FCV-333-A, FCV-333-B and _FCV-3431A, FCV~343-B. These normally-closed, air-operated valves are inter- locked to close on & sudden rise in reactor cell pressure. Lines 334 and 344 permit the application of a test pressure between the two flow-control valves to check for leak tightness. The reactor and drain tank cells can be depressurized for leak testing through the_Jet discharge lines. - A sink in the change room, located east of the high bay, and part of the controlled ventilation area, has a drain, line 340, leading to the ) waste storage tank. A funnel is provided in the high-bay area for the % £y e - 401 addition of caustic to the liquid waste tank, through line 339. (The liquid waste is made a basic solution before transfer to the Melton Valley waste disposal system.) | The discharge of the waste pump, located in the remote maintenance practice cell, may be directed into the waste storage tank through the 2-in. sched 40 stainless steel line 301. The waste pump discharge may also be diverted to the waste filter located in the liquid waste cell through the 2-in. pipe, line 302. The discharge of the waste filter is through line 306 to be returned either to the decontamination cell or de- contamination tank. Line 307, connecting the waste pump discharge to line 306, permits recirculation of water in the decontamination tank, or partial by~passing of the filter when recirculating the water; it also allows pro- cess water to be added to the waste storage tank via lines 819, 306, 307 and 301. The sump pump drawing liquid from the 55-gal contaminated storage drum, referred to as the "pit pump" to distinguish it from the sump pumps also located in the sump room, can discharge into the liquid waste tank through a 2-in. pipe, line 326. The pressure relief valves in the treated water system serving the reactor and drain tank cells discharge infio the l-l/h~ in. line 335, which joins the afore-mentioned line 326 for release into the waste storage tank (See Section 15.10). The waste tank is vented through the 6-in. sched 10 stainless steel pipe, line 948, which leads to the remote maintenance practice cell, where a small in~line blower of 180 cfm capacity is installed in the pipe to pro- vide a positive movement of the gases into the containment ventilation ex- haust system (See Section 13.3.2): ' The only bottom connection on the waste storage tank is line 300, a 2-1/2-in. sched 40 stainless steel pipe leading to the suction of the waste pump in the adjoining cell. The bottom of the decontamination tank in the decontamination cell also drains into line 300, and the pump suction, through & 2-1/2-in. pipe, line 304. The sump in the floor of the decon- tamination cell can be pumped out by the waste pump through line 303, which Joins the afore-mentioned line 304 inside the decontamination cell. The waste pump discharges through line 305, a 2-in. sched 40 stain- less steel pipe containing a pressure-measuring tap and sample point. 402 Downstream of valve 305-A, the pump discharge line continues as & 3-in. cast iron pipe to the central pump station of the Melton Valley waste system, which is located just west of the Bldg 7503 area. The sump in the sump room receives general building drainage, as listed in Table 14.1. This water will not normally be contaminated. Two 1.5-hp 75-gpm float-controlled sump pumps remove the water and dis- charge it through a 3-in. pipe, line 327, to a concrete catch basin. This basin, about 2 x 3 ft and 6 ft deep, is located just west of the charcoal bed and has a bottom elevation of 846 ft. It drains through a 150-ft-long 12-in. reinforced concrete pipe away from the site toward the natural drainage leading to Melton Branch. The overflow line from the charcoal bed cell empties into the above- mentioned sump pump discharge, line 327 and thence to the catch basin. Line 327 1s provided with a check valve upstream of this connection to prevent the overflow from moving backwards down the line into the sump. It is possible for contamination to be present in the drainage from the bottom of the filter pit and from the bottom of the containment ventilation system exhaust stack. Each of the two 2-in. stainless steel drain pipes from the filter pit has a sight indicator and a hand valve in the concrete filter pit valve box located just east of the filter pit. The two lines combine, as line 351, and join the 3-in. cast iron drain line from the bottom of the stack, line 350, which in turn empties into the 55-gal stainless steel drum in the sump room. The 5-hp pit pump can remove water from the drum through the 3-in. suction, line 325, and discharge it via line 326 to the liquid vaste storage tank. 1If there is no objectionable contamination, the drainage water can be pumped through line 330 and 331 to the above-mentioned catch basin for release to the natural drainage from the site. Check valves in both lines 326 and 330 prevent backflow into the sump from the pump dis- charge lines. Line 328 is a 3-in. cast iron pipe installed to drain water from the charcoal bed cell. A similar arrangement is provided in line 329 to drain water from the reactor containment vessel cell annulus. It is unlikely that either of these spaces will be drained frequently. The two.drain lines combine in the sump room to join line 325 at the pit pump suction. 403 Table 14.1 Lines Emptying into Sump in Sump Room Line Number 352 353 354 355 356 357 358 359 360 361 362 363 364 365 Size Type ~ From 3 in. CI Bottom of radiator air duct 3 in. CI | Bottom of radiator cooling air stack 3 in. Steel Bottom of coolant drain cell 3 in. CI Blower house 3 in. Cl Blower house ramp 3 in. CI West tunnel 4 in. CI Service room 3 in Steel Service tunnel L in.. CI Service tunnel French drain Y in. - CI Reactor cell French drain 4 in. CI Charcoal bed cell French drsin 4 in, CI French drain for SE area of bldg. 3 in. CI Coolant drain cell 2 in. CI Vent house valve pit 404 The water can thus be pumped out of the sump room by the pit pump to the waste storage tank or to the natural drainage from the site. If necessary, it could also be dumped into the sump room sump for removal by the sump pumps . Check valves in both lines 328 and 329 prevent backing up in these lines due to the difference in elevation. The reactor cell annulus is also provided with an overflow pipe, line 331, which drains to the catch basin outside. A check valve in line 330, from the pit pump discharge, which Joins line 331, prevents the overflow water from moving backward through the pump into the sump. 14 .3 Description of Equipment 14.3.1 Liquid Waste Storage Tank The waste storage tank is 11 ft diam and 16 ft high, giving a storage capacity of about 11,000 gal. The tank is always vented to operate at es- sentially atmospheric pressure. The tank has a flat bottom resting on the concrete floor of the waste tank cell. The top is a dished head contain- ing & 12 x 16-in. manhole, eleven flanged nozzles for inlet lines, and a 6-in. nozzle for the vent line. The discharge is a 2-1/2-in. dip pipe to the bottom which penetrates the tank wall about 18 in. above the lower circumferential weld. The tank is made of 1/4-in. 304 stainless steel (See ORNL Dwg D-KK-B-41283). 14.3.2 Waste Filter The waste filter is & Cochrane, Type A, vertical,pressure filter. The tank is 3 ft 6 in. in diam and 48 in. high between the head welds, and has dished top and bottom heads. The tank is rated at 100 psig, but is not a Code vessel. The filter bed consists of a 34-in. depth of graded sand and gravel having a cross sectional area of about 9.6 ft2. Water enters through a 2-in. pipe in the top head and is distributed uniformly by a concave baffle. The underdrain is through a convex, slotted diffuser plate welded to the bottom head. The capacity is 4 gpm/fta, or a total of 38 gpm, with | a maximum pressure drop due to flow through it of 5 to 10 psi. The filter can be cleaned by back washing with process water, the normal back wash ¥ it 405 requiring 5 to 15 min at & flow rate of 10 to 15 gpm/fte, or a total of 96 to 14k gpm, at pressures of 20 to 25 psig. 14.3.3 Waste Pump The waste pump is located in the remote maintenance practice cell. It is & canned-motor unit, Chempump Type CH-5, and has & 2-in. suction, a 1-1/2-in. discharge, and a 6-1/2-in. impeller. It is rated at 150 peig and will deliver 140 gpm againSt a head of 80 ft. The motor is rated at 10 hp, and it is supplied with 3-phase, 60-cycle power from the 50-amp circuit breaker No. 23 on the G-4 motor control center. 14.3.4 Sump Pumps The two sump pumps in the sump room are rated at 75 gpm, with a dis- charge head of 40 ft. The motors are rated at 1.5 hp. The power supply is through motcr control center G-3-3 and a 30-amp circuit breaker. The pumps are controlled by float-operated switches. 1%.3.5 Pit Pump The pit pump in the sump room is a Peerless unit rated at 200 gpm at a discharge head of 70 ft. It has a 3-in. suction and a 2-in. discharge. The motor is rated at 5 hp. The electrical supply is through the motor control center G-3-3 and the same 30-amp circuit breaker used for the sump pump, described above. 14.3.6 Jet Pumps The jets used to evacuate the sumps in the various cells are Penberthy ejectors, Model X196, Series 2A (Penberthy Manufacturing Company), having cepacities at various conditions as listed in Table 14.2. The sump jets normally Qperate with a suction head of about 2 ft. and the caustic scrubber Jet has a suction head of about 12 ft. The jets in the reactor and drain tank cells are air operated and those in the éuxiliary cells are actfiated by steam. 14 .4 Design Criteria ~ The primary requirement of the liquid waste system is that all 406 Table 14.2 Sump Ejector Characteristics¥ Pumping Water Suction Head Steam or Air Supply Pressure £t H20 30 psig 60 psig N psig Water delivery (130°F) 2 8.5 gpm 8.1 gpm 7.25 gpm Water delivery (130°F) 10 4.6 gpm 6.6 gpm 5.75 gpm Steam consumption Air consumption Air capacity at suction (at 40 psig supply pressure) 1.3 lbs/min 1.9 1bs/min 2.6 lbs/min 26 scfm 38 sefm 52 scfm Pumping Air Vacuum, in. Hg 5 10 15 20 50 scfm 17 scfm T scfm 4 sefm *¥Penberthy Mfg. Co. Ejector Type XL96 Series 2A. i} 407 agueous effluent from the MSRE which might be contaminated be collected and stored, treated with caustic when necessary, and discharged to the central pump station of the Melton Valley waste system, located just west of the Bldg 7503 area. ' Although not a direct part of the system, the liquid waste arrange- ment also includes provisions for collection of certain non-radioactive general building drainage and disposing it to the natural drainage from the site. This general building drainage does not include storm water or that from the sanitary system. A requirement for operation of the decontamination cell is that the shielding water be circulated through a filter to permit better visibility for underwater operations. The jet ejectors used to remove water from the sumps in the reactor and drain tank cells are operated by dry air rather than by steam to avoid the introduction of moisture into the cell. The Jjets removing water from the sumps in the auxiliary cells are steam-actuated. The steam is con- densed and easily retained. 408 15. COOLING WATER SYSTEM 15.1 Iayout and General Description The MSRE cooling water facilities include the potable water, process water, cooling tower, treated water and condensate systems. The potable water system distributes water supplied from the X-10 area of ORNL, as described in Section 3., This system provides for fire protection, sanitary uses and drinking water. A portion of this potable water, after passing through a back-flow preventer, supplies the process water for cooling tower make-up, etc. The potable water supply line is at the north end of Bldg. 7503 and enters the building at the northeast corner. The cooling tower water system is a circulating system in which the water is cooled by a 2.75 x 10°® Btu/hr forced-draft cooling tower located southwest of the building, see plot plan, Figure 3.2. Either of two outdoor 20-hr, 80-ft head, centrifugal pumps of 547 gpm capa- city, circulates water from the tower basin to the treated water cooler and other equipment listed in Table 15.1. Water from the cooling tower is also used to cool the charcoal beds but this water is discharged to drain and is not circulated. The treated water system is a closed circulating system contain- ing condensate with an added chemical inhibitor to minimize corrosion. Water from this system is used for cooling equipment in which there is a possibility of the water becoming contaminated. The equipment cooled is listed in Table 15.2. The water is circulated by either of two 20-hp, 136-ft-head, 320-gpm centrifugal pumps located in the water room in the blower house at the southwest corner of Bldg. 7503. The treated water passes through a shell-and-tube type heat exchanger in the Diesel house to be cooled by the cooling towérrwater‘system. The water is distributed by d header in the water room and metered to the various items of equipment. The return lines discharge into a common header leading to the pump suction. A surge tank is provided for the expansion of the water in the closed system. This vented - 409 Table 15.1 Equipment Cooled By Cooling Tower Water Flow, gpm Heat Removed, Btu Treated water cooler 260 1.53 x 10° Air compressors (total for 3) 36 0.36 x 106%x Fuel pump lube oil system 7.5 0.035 x 106 Coolant pump lube oil system 7.5 0.035 x 10° Drain tank condensers (each of 2) 40 1 x 106 %% Caustic scrubber and HF trap 5% * Reactor cell annulus ‘ * * Air conditioners (total for 3) 84 0.336 x 108 Steam condenser 17 0.5 x 109 Charcoal beds * * Coolant cell coolers (each of 2) 0.168 x 10° Reactor cell annulus makeup * TOTAL 3.94 x 10 Table 15.2 Equipment Cooled by Treated Water Flow, gpm Heat Removed, Btu Reactor thermal shield 100 - 0.41 x 10° Fuel pump motor 5 0.005 x 10° Coolant pump motor 5 0.010 x 10° Reactor tell air coolers (total , , for 2) o - 120 0.512 x 10° 'Drain_tank cell air cooler 60 - 0.256 x 106 Nuclear inStrumefit;penetration % | * Gas codlant_pump lube Qilsystem 10:} 0.237 x 106 Gas cooler ' - 20 ¥ = Intermittent operation *% = Maximum vslues 410 tankhas a float-operated valve for makeup from the condensate system and has provisions for addition of corrosion inhibitors amounting to 2,000 ppm of potassium nitrate (75¢4) and potassium borate (25¢). Condensate is used for makeup in the treated water system and for makeup to the boiling water decay heat removal system in the fuel drain tanks. The condensate 1s provided by condensing steam supplied from the X-10 area of ORNL. The shell-and-tube type condenser is - located in the water room and is stored in two nearby 500-gal tanks. i - 15.2 Flowsheet The cooling water system flowsheet is shown in Figure 15.1 (ORNL~-DWG-D-AA-A-40889) and includes the cooling tower, treated water and condensate systems. The potable water supply is also shown in- sofar as it is connected to the reactor processes, but does not in- clude building services. Appropriate flowmeters and indicators are provided at all points in the system where water flow rates are needed for heat balance cal- culations. In general, these are not mentioned in the following discussion, as they are covered in detail in Part II. 15.2.1 Potable and Process Water Two 6-in. carbon steel pipes supply Bldg. 7503 from the water main at the road. One is a potable supply for general building use. - The other, line 894, supplies the reactor processes through a 4-in. backflow preventer. The backflow preventer, BFP-890-1, has a relief line discharging to a floor drain in the north end of the main build- | ing, and isolation valves V-894-Bl and V-890-Al, which can be closed for maintensnce. Additional valves, V-894-B2 and V-890-A2, are pro- vided in event it is necessary to install an additional backflow preventer for temporary use. | Water from the backflow preventer is distributed through 890, a 6-in. header.* A branch from the header, line 896, supplies process water for general process use in the high bay area. Line 892 is a C *Water taken from this potable water header is sometimes referred to . in this report and in the MSRE literature as process water. \ R R UL I L 12 X b * e 411 A ettt 1t i At et s e " < o E r e H ! J I i" e e— . =856 6-40-S—— 523 4PM—, CTWR= - L 227 oPM—, . —4-40-8 FroylinceM ] ‘ = N o . . > /—na 1b- STEAM L e ¥ - w N N _______ N ] fi‘— SRR . IESEL HO £8ans 1 l | " — @D 7 Zvesase ' DIESEL HOUSE . - 854 @ vesam Xveara , — (8200 r N o Vel 1 8 e, @ WATE= o . o o ROOM l—l ‘ \\U; l’ 3 x VB30A2 V88034 £ 5 - ' S 3 E x uy f = w E" X 2 le - ° oyl OFFICE s 'R L 5.1 = 2 = BLDS, & 8o 1z aw | W : & A M ol & Q g vears @ _ Asios & o |5 71 s - CONDENSER CTLaNT 2 . : (. z o Cad 3,1 8 z Z CHLER g h £ le ey - HAP EAST . a . n u o z INSTRUMENT AIR INSTROMENT Al [ SERVICE AIR 2i 11 a Qo vRAZA COMPRESSOR COMPRESSOR NO.2 | comPRESSOR o 8 © i % WTERATTERT & 2-a0- 1 DDEAD END o OPERATIMN . » ]I?c EX'STING : w g ' ‘ 1 - g Hpl—pumes v P YO LIQUID L ‘ @ 2 . {NOT SED) I WASTE SYSTEM [ S—— SERVICE 1i-an.s L_n....j ' ' '_'7;3_ Y veazs TUNNEL * _1 . NORTH. END_OF BLDG, 750 FI . \.,) ® — _ T 330516 CED » - %0 . "'-'I_(B-a ] ] “ ] (;-_ QCY 4 827> <&20> - D \ h : )-——N—...—..@__ L § ~ g ] FA va4ib 847A BUOWER x® = (3) CONLING TOWER \873 ;3 voarc |vears HGLUSE & w 49 i PUMP NO. 1, - ! _a0-s8 2 z Je SZV893C . ¥ 3 e D z o JE X : 112 i)E £ d 518 b & s o IM! j-40-35 A ) (J i © v one 3 2 2| 2 2 7 | 10 GPM—g l VONT ) (vare < g = 2 ‘ V-CST-10 ¢ 7 z z ‘ V-CSTIC a < ve 1}-40s ) & & ve93C w3 4 g 1REATED WATER 35 PUNP N, 2. & TO CHARCOAL | e COOLING TOWER PUMP DATA Sgg - — BED CELL i -y FLOW S50 0PN gg \d HEAD e0' 1 Ly (812>~ WORSE POWER 20 © vezsa }{ v-CsT-2 A~ WATER ROOM g T RPM 1745 v - Xocereo Lo (5 s . @ SP Y{venza ok . S.B 4405 B! vaac 2: i n | e — s— . c2gse $= THIS DRAWING REFLECTS cvezs 40 " >9 > . 12088 TREATED WATER PUMP DATA 3 § el AS BUILY veal [ T Q T - ] . — | @ ~SLUTION i 40-53 ::; PEEALESS m-u Ifi S . — - E_ I CHANGES x Tom e el Fy.sre WEAD e 18 psta ! s z | oATE._9-25-64 ® VSR SPRING LOAD ARUPTURE - . & | Yvezss 24 CLOSE. RORSE POWER 20 oIsc ¢ 3 " v-57-C venzg veo3 Y g « - - : 3 3 new 1780 « _ & = [—" ' Y e 2 N sroe aw 3 “ & ¢xo ¥ ! w J 1 - = @J K @ ezl cvens il & 2 . § 8 = - 3‘ 5& g’ z o . 3 LIOWD WASTE SYSTEM ID-AA-A-40888 (st} x & O & 2 o @ 3 5 vsr ‘ & v i S & S g % 08: §i‘ gi'_' g E z 4 g‘ 2 FUEL PROCESSING SYSTEM D-AA-A-40887 o < x a W = pkx v - < @ Zyezro V-ST-A @ @ 3 g I 3 : 2 2 — §= 93: 4 3 3l e g é z , CIL SYSTEM FOR FUEL & COOLANT PUMPS [DAA-A-4088S . x - J @ & 2z @ b 3 \ T ki z g &, s : MY 3% ggg I & t.‘; U: 2 & g 5 u IFF GAS SYSTEM & CONTAINMENT VENTILATION [0-AA-A-40883 = o Q x z Z © = . gy s Zx : 3@ § xz o= g T 8 © £ F-EL CRAIN TANK SYSTEM 0-84-A-40882 ) ) 20> g 2 § g z 228 & T [ z 0 vk o u o g 5 srien vE E oo & £ £z ¢ g | T ) z :‘g &z U = £ 4 CODLANT SYSTEW Dar-a-40801 @ b ° = - [3 ' o < I— [ —— o s w o 0= g 5 s g'.; & & zL‘?, § & w € FUEL SYSTEW C-A4-A-40880 ] x - a x © & z ¥ > @ 3 é g > g g @ s a - 4 x TA FEED WATER TANKS g & R g pepEg g°® E &3 ka3 P & g 2 & WATER SYSTEM INSTR, APPLICATION MAGRAM [D-AA-8-40509 . : REFERENCE ORAWINGS owe. Ro. THRN, Y, e . ISty "\A’ il 2 L S S I e OAK RIDGE NATIONAL LASORATORY i 28 nr &/ FRF Bt S . B‘-i: s erup— COOLING WATER SYSTEM - (%3 [ T PR 9% | ¢ | 9E€ OCn 29% e ;_""Z. (L 5| s« OCESS FLO_W SHEET P BSEE ock Zew ¥ L U0 M.S.R.E. 2499 E OCN 2491 5 BN Aol Ao /Q( 08 LL L, [Tl chrm: None JO® 433-1,0 J D-AA-A40B89-C A . c o K » THIS ORSIGN 1§ THE PROPEATY OF UNIOM CANBIDE NUCLEAR COMPANY —DIVISION OF UnMigN CARBIDE CORPONATION L35 JTTves veum ve FlGURE '5. I ¥ jk b I 1 e 412 1-1/2-in. pipe for supplying water to the vapor condensing tank used in the vapor condensing system for the reactor containment cell. The liquid waste cell is supplied with potable water through the 2-in. line 819. A backflow preventer in this line, BFP-819, is located in the west side of the liquid waste cell, and prevents contamination of the cooling tower water system by reverse flow. | Emergency cooling water is supplied to the two instrument air compressors and the service air compressor located in the Diesel house, through 2-in. line 872. These units are normally cooled by the cooling-tower water system. The condensers in the fuel drain tank decsy-hest removal system slso have an emergency water supply from the process water system through the 2-in. line 882, and three- way valve HOV-882. The normsl coolant for the condensers in the drain tank system is cooling tower water. Line 890 continues as a l-l/2-in. séhd 40 pipe to provide makeup for the cooling tower basin through the float-operated valve, ICV-890. | 15.2.2 Cooling Tower Water System Water from the cooling tower basin is supplied through a 6-in. pipe, line 850 and 852, to the suction of the cooling tower water circulating pumps. Pump No. 1 discharges through a check valve into line 851 and Pump No. 2 into line 853. This water, at about 35 psig, and a maximum temperature of 85°F, is distributed through the 6-in. header, line 851. A major take-off, also numbered 851, is a 6-in. pipe supplying about 260 gpm of cooling water to the shell-and-tube cooler in the treated water system. This water circulates back to the cooling tower through lines 854 and 856. A 1-1/4-in. pipe, line ‘880, is connected to line 851 for the 36-gpm cooling water supply to the instrument air and service air compressors, and associlated after- coolers, all located in the diesel house. The water is returned through lines 881, 854 and 856, The other major branch of line 851 is the 3-in. take-off, line 860, supplying a subheader, line 816. Lines 821 and 823, each 1-1/4 in. supply about 7.5 gpm from this header to the fuel and coolant salt circulsting pump lubricating oil system coolers located in the 413 service tunnel. This water returns to the cooling tower through lines 820 and 822 via lines 817 and 856. A 1-1/2-in. pipe, line 891, from line 816 is used to fill the annulus around the reactor cell containment vessel, The caustic scrubber cooling jacket in the fuel processing cell is supplied through line 842 and returned through line 843, A take- off from the 3/4-in. line 842, the 1/2-in, line 839, supplies water to the cooling Jjacket on the HF trap and HF cylinder in the area out- side of Bldg 7503, just west of the drain tank cell. The cooling water is returned through lines 843 and 849, via lines 817 and 856. Line 816 also supplies water to the steam condenser in the water room, previously mentioned as the source of water for the condensate system to be described subsequently, through the 1-1/4-in. line 814. This water is returned through line 815, Also as previously mentioned, the drain tank heat removal system condensers are supplied with about 40 gpm each of cooling water through the 2-in. pipes 810 and 812, through a three-way valve HCV-882. The return water lines from the condensers are numbered 811 and 813. The main cooling tower water return header, line 856, is a 6-in. pipe leading to the top of the tower. A 3-in. subheader, line 817, collects much of the water flowing into this main header. Line 856 divides to supply both sections of the cooling tower. The water is normally returned at a temperature no hotter than 95°F, and under maximum smbient wet bulb temperature conditions of 79°F could be cooled to 85°F (7°F approach). Since the commonly-used design wet bulb temperature in the Oak Ridge area is 75°F, cooler water tempera- tures can be attained, particularly during the winter months. A 4-in. by-pass, line 858, Jeads through the control valve, TCV-858, to the tower circulating-pump suction to regulate the pump discharge temperature. 15.2.3 Treated Water System Condensate from the storage tank in the water room is added to the treated water system surge tank, located directly beneath it, 414 through line 825. This 1-in. pipe contains a float-operated control valve, ICV-825, to maintain an operating level in the tank. The surge tank is vented to atmosphere at all times. Potassium nitrite (75%), and potassium borate (25%) are added through a funnel to inhibit cor- rosion in the treated water system. The surge tank is connected to line 827 by two pipes, one on each side of valve V-827-C. The down- stream line is a direct connection to line 827 and the upstream one contains a valve, V-827-D. This arrangement allows some of the flow in line 827 to be diverted to flow through the surge tank for mixing purposes and also assures that the surge tank is always connected to the system. The above-menticned line 827 is a 4-in. header leading to the suctions of the treated water circulating pumps. A duplex strainer is included in the line upsiream of the surge tank connections. The pump discharge lines, 829 and 835, combine to form line 829. This e in. pipe delivers the water at 100°F and 58 psig, and at a flow rate of about 300 gpm, to the treated water filter located in the Diesel house. The filter when clean has a pressure drop of less than 1 psi and a maximum pressure drop of 5 psi, and removes essentially all particles greater than 30 microns in diameter. After leaving the filter the water enters the treated water cooler, where it is cooled to about 90°F. It leaves the heat exchanger at about 43 psig through the 4-in. sched 40 distribution header, line 826. The following equipment is supplied from this header in the water room, each connection being provided with a hand-operated regulating valve, a flow indicator, stop valve, check valve, and a sampling valve arrangement to test the leak tightness of the check valve: (). The thermal shield for the reactor is cooled by 60 gpm of treated water supplied through a 2-1/2-in. pipe, line 844, and re- circulated to the system through line 845. A normally-open block valve on the supply, FSV-844, is controlled by a pressure switch, PSS-844B, on line 844 to limit the water supply pressure to about 16 psig. A flow-limiting orifice in line 844 also prevents over- pressuring the thermal shield if the manual flow adjusting valve, V-844A, is opened too wide. Line 844 contains a check valve upstream R 415 of the orifice to prevent back flow. Rupture discs, rated at 18 psig, in lines 844 and 845 discharge to line 855 leading to the vapor condensing system. _ (b) The fuel pump motor ecooling water is taken from line 844, described in (a) above, downstream of the block valve FSV-844. This l-in. pipe, line 830, is provided with a check valve, located in the blower house. The required flow rate is about 5 gpm and the water is returned through line 831. This line, and the return water line from the thermal shield, line 845, combine in the blower house to form line 847. This line contains a block valve, FSV-847, which is also controlled by a radiation monitor, RE-827. (c) The reactor cell air cooler (No. 1) is supplied with 60 gpm of treated water through the 2-in. 1line 840. This line includes a check valve located in the blower house. Water is returned from the air cooler through line 846, through a block valve, FSV-846. A relief valve set at 100 psig is included in the return line upstream of the block valve to vent excessive pressure through the 1-1/4-in. line 335 to fhe waste tank. (d) The other reaétor cell air cooler (No. 2) is supplied with 60 gpm of treated water through line 838 in the same manner as the cooler connections described in (c), above. The return water is through line 841. (e) The coolant salt pump drive motor requires about 5 gpm of cooling water, supplied through 1l-in. line 832, and a check valve, CV-832. The return water is through line 833 directly to line 827. (£) The 60-gpm tréated'wafier supply to the drain tank cell air cooler is through line 386, a 2-in. sched. 40 pipe with a check valve located in the blower house. The feturn water pipe, line 837, is equlpped with a block valve, FSV-837, and a relief valve venting to 1ine 335, in a similar arrangement to the reactor cell air coolers. (g) The nuclear instrument tube penetration is filled with water from the treated water system The water is supplied through the 1/2-in. pipe, line 848. o 416 (h) The aftercooler used downstream of the component cooling system gas blowers, located in the special equipment room, is cooled by 20 gpm of treated water supplied through the 1-1/4-in. line 873, and returned through line 874. The oil coolers on the two blowers are also water-cooled by about 10 gpm of water supplied through line 875. The water is recirculated through line 876, also l-in. pipe size, which joins the above-mentioned water return line from the aftercooler, line 874, before discharging into the return header, line 827. 15.2.4 Condensate System Saturated steam at 15 psig is condensed in a shell-and-tube heat exchanger located in the water room at the southwest corner of Bldg 7503. The condenser is cooled by cooling tower water, as described in Section 15.2.2. The condensate leaves through a 1/2-in. strainer and steam trap on the stainless steel line 801, and discharges into the vented condensate storage tank, No. 1 or to tank No. 2 through the branch line 818. The drain from the bottom of tank No. 1, line 802, and from the bottom of tank No. 2, line 825, combine as the 1- in. line 883, and is used to feed the float-operated make-up valve on the treated water system surge tank. Lines 802 and 803, both 1/2-in. stainless steel, also branch from line 883 to supply makeup to the drain tank heat removal system water tanks. 15.3 Description of Equipment 15.3.1 Condensate Storage Tank No. 1 Condensate storage tank No. 1 is a vertical, 36-~in.-diam vessel with an overall height of 5 ft. The tank is vented to the atmosphere at all times. It is constructed of 12-gage, 304 stainless steel, with dished heads 3/16 in. thick. The tanks are supported by three angle iron legs, with the bottom of the tank about 4 ft from the floor. The tank has six nozzles, the three in the top being the 1/2- in, water supply, the 1/2-in. vent, and a 1l-in. spare connection. 3 ’ 417 There are two 1/2-in. couplings on the side for the water level gage. The l-in. drain line connection is in the bottom head. 15.3.2 Condensate Storage Tank No. 2 This tank is similar to condensate storage tank No. 1 but is a horizontal tank 30 in. diam x 72 in. long. The cylindrical portion is 12-gage 304 stainless steel with 3/16-in.-thick dished heads. The tank is designed for operation at atmospheric pressure. There are four nozzles at the top: the 1/2-in, inlet, the 1/2-in. vent, and two sPares. The two side nozzles on one end are for the water gage. A 1-in. diséharge nozzle and a 1/2-in. drain are provided along the bottom. The tank is supported by a steel cradle 78 in. from the floor. This tank was arranged horizontally rather than being identical to tank No. 1 in order to install it directly above the surge tank. 15.3.3 Treated Water Surge Tank The surge tank is a horizontal 30-in. diam x 48 in. long carbon steel tank designed for atmospheric pressure. The wall thickness is 1/8-in., with 3/16-in., dished heads, The nine nozzles include: 1l-in. feed line at the top, a 1-in chemical addition 1line, and a 1/2-in. vent. Two nozzles at one end are for the water gage and on the other end two nozzles connect to the float-operated liguid level controller. Two l-in. pipe size nozzles are at the bottom. The tank is supported on a cradle 30 in. sbove the floor and directly under condensate storage tank No. 2. &15.3;4 Cooling Tower 1 The -cooling tover is designed to cool about 550 gpm of water from 95°F to-SS?F;fihen the wet bulb temperature is 79°F. The equi- valent heat removal capacity is 2.7543 10° Btu/hr. The connected cooling tower load is'about 538 gfim and a possible heat load'of_a ‘maximum of 3.94 x 10° Btu/hr, as was indicated in Table 15.1. The tower has e capacity of 3.57 x 10% Btu/hr when the wet bulb tempera- ture is 76°F wbt. The design wbt in common use in the Ozk Ridge area is 75°F. 418 The cooling tower is a Marley Company Model 8320 "Packaged Aquatower" with two 60-in. diam multi-blade adjustable pitch fan belt driven by 5-hp, 1800-rpm, TEAO motors. The overall dimensions are 11 £t 9-1/2 in wide x 14 £t 6-7/8 in. long and 8 £t 8-3/4 in. high. 15.3.5 Treated Water Cooler The treated water cooler is a heat exchanger made asvaileble from another project. It is a shell-and-tube type, four-pass, horizontal heat exchanger, and is located in the west end of the Diesel house. The shell is 28 in. OD x 20 ft long, not including the heads, and has 10-in. flanged nozzles. The 360 straight tubes are admiralty metal, 1 in. OD, No. 18 BWG, 20 ft long, spaced on 1-1/4-in. squares. The tubes are supported by fixed tube sheets and baffle plates of naval brass. The tube-side connections for the treated water are 8-in. flanged nozzles. The total heat transfer surface is 1,885 ft?, the shell-side water velocity is about 0.48 ft/sec and the tube-side velocity 1.75 ft/sec, providing an estimated overall heat transfer coefficient of 232 Btu/hr- £t2-°F.196 (perating design conditions are that the cooling tower water enters the shell at 85°F and leaves at 97°F. The treated water enters the tubes at 100°F and leaves at 90°F.157 15.3.6 Treated Water Circulating Pumps There are two identical treated water circulating pumps, one operating and one for standby. Each is sized for 1204 of the 96-ft 158 and for a flow of head of pressure drop estimated for the system about 310 gpm. The units are Peerless centrifugal pumps, Model 2 x 3 x 13 DL, driven by 20-hp motors. The open-type impeller is 13 in. in diam and operates at 1,750 rpm. The characteristic curves of pump performance are shown in Figure 15.2. Each pump and motor is mounted on a common base, about 18 x 49 in., and the unit is about 26 in. high, arranged for top discharge. Total Head - Ft 419 Unclassified ORNL DWG 64-8843 180 0% 45 ~ lj-in.g 160 < e —-60 12-in N N\ 1%0 5 N\ < 62 60 - N, ‘(\ 2N =0 N 55 | N 6l \ } N 100 ‘ N 10-in. \ d?l\L \ 20 EP & ‘ \\ v Y ] \ N 60 i ><\) N5 Peerless Pump ) 50% 2x3x15 M & DL %0 — 1750 rmm 10 HP — 20 Efficiency Curves . | | Figure 15.2. 100 200 300 40O 500 Gellons per Minute Charscteristic Curves - Treated Water Circulating Pumps 420 15.3.7 Cooling Tower Pumps Two identical cooling tower water circulating pumps are installed, one to serve as standby. The units are American-Marsh centrifugal pumps, size 4A, Type RDM. The pumps have 10-in. diam inclosed impellers and are direct driven by 20-hp motors at 1,750 rpm. The estimated pressure drop in the system is 53 ft of water. The units were selected for 80 £t of head at 550 gpm capacity. The characteristic performance curves are shown in Figure 15.3. The pump and motor are mounted on a common base, 15.3.8 Steam Condenser for Condensate System The steam condenser is a horizontal shell and tube type, with a carbon steel shell about 8 in. OD x 6 ft long, made available from another project. Condensing is inside the stainless steel tubes and the total capacity is about 1.2 gal/min. 15.3.9 OSpace Coolers The five space coolers in the MSRE processing cells are designed to maintain the cells at temperatures below of 150°F. There are two units for the coolant cell, two in the reactor cell and one in the drain tank cell. 15.3.9.1 Coolant Cell Coolers. - The two space coolers for the coolant cell were existing units in Bldg 7503. They are external to the cell, located at the 850-ft elevation, and connected to the cell with short ducts. BEach unit is mounted in a gas-tight, 12-gage sheet metal casing, one on the northwest side of the cell and the other on the southeast. The two return ducts to each unit are 12 x 19 in. and the discharge duct is 23 x 28 in. The two coolers are identical and are Trane No. 212 units with an 8-row water coil and a rated cooling capacity of 250,000 Btu/hr.* The cooling load on each unit is estimated to be about 82,000 Btu/hr 159 e circulsting when the cell temperature is the maximum of 150°F. fans have a capacity of 3,600 cfm at 167°F, and are driven by 2-hp, 220/440 v, 3-phase motors designed for operation at 175°F. The cooling water requirements are estimated to be about 20 gpm. *See ORNL Dwg for ART Project, D-KP-19040-T Rev. 2, Dec. 8, 1955. Ft Total Head 100 60 ORNL DWG 64-8844 Unclassified 10~in. _ ‘ N ~ ’ 20 HP | f\ ~ \R N T~ . N 9-in. ~ \ ™~ ' \ 7-1/2} |~ | L~ \ = N sin 1] % hot 50 / American-Marsh Centrifugal Pump Type RS-RD, Size 4A, 1750 rpm Enclosed 10-in. Dia. Impeller | 7 3 s’ \ Brake Horsepower 9-in. // — / ______.// 8-1n. / —-_‘4/ 100 300 400 500 600 T00 800 Figure 15.3. Gallons per Minute Charscteristic Curves - Cooling Tower Water Circulating Pumps 5 & 8 Brake Horsepower A% | ey 422 Table 15.3 Design Data Reactor and Drain Tank Cell Space Coolers Number of units: In reactor cell In drain tank cell Design pressure Required cooling water for each unit Water temperature rise Water pressure drop Air flow rate Air temperature drop Air pressure drop Rated heat transfer capacity¥ Fan Motor Coil Approximate weight Dimensions 2 1 150 psig 60 gpm 9°F 2.1 psi 7,400 scfm 32.3°F 0.6 in. Hy0 256,000 Btu/hr (75 kw) Louis Allis, 3-hp, 3-phase, 60 cycle, 440 v, 1,750 rpm, Class H, totally inclosed Aluminum, 6 blades, 32 in. diam 69 ft? effective prime surface, 950 £t? fin surface, red brass serpentine coil, 5/8-in. OD x 0.035-in. wall tubes, 0.010 in. fins mechanically bonded to tubes 1,600 1bs (with water) About 50 in. x 29 in. x 44 in. high *Entering air assumed at 150°F. r o 423 15,3.9.2 Reactor and Drain Tank Cell Space Coolers. - The reactor and drain tank cells are estimated to require the removal of a total of about 500,000 Btu/hr to maintein the cell temperature below 150°F. Two 8pa¢e coolers are used in the reactor cell and one in the drain tank cell. The units are identical and are Young Radiator Company Model 55, modified for direct drive and installed to facilitate maintenance using remotexy-ofierated'tooling. The water tubes and headers are bagkbrazed to reduce the likelihood of water leaking into the cell. The treated water supply and return lines are connected by ring-Jjoint type flanges, which are monitored for leakage. Design date for the coolers are listed in Table 15.3. 15.3.10 Piping Valves and Appurtenances 15.3.10.1 Piping. - All water system piping -located outside the containment cells is sched 40 black steel, ASTM A-53. Pipe and fittings above 1-1/2-in. pipe size are butt-welded, and the fittings are ASTM A234 Grade B. Smaller pipe and fittings are threaded; the fittings are 150~-psi black malleable iron. Condensate piping is 304 stainless steel with standard weight screwed fittings. All water system piping-inSide the cells is 304 stainless steel, sched 40, with butt-welded ends. Flanges are either 150-psi or 300 psi weld-neck, rihg—joint flafiges, depending on service and location. All of these joints are leak-detected. 15.3.10.2 Valfies;'Q Velves of 2- 1/2- in. size and over have flanged'ébnnéctions. The gate valves are l25-p81 Fbrrosteel wedge valves with.bronze trim and ‘outside screw and yoke, Crane No. 465-1/2. The gldbe valves are Ferrosteel with Joke bonnet, ‘bronze trim, Crane No. 351. Bronze trim 1s also used in the l25-psi Ferrosteel swing check valves Crane No. 363. Valves used in piping 2 in. and‘smaller_haverscreWBd ends; The -‘gate valves are 125-psi bronze valves with rising stems, Crane No. 430-UB. Globe valves are 150-psi bronze, Crane No. 14P. Except as noted below, the check valves are 125-psi bronze, Crane No. 34.. The check valves in lines 836, 838, and 840, which supply treated water to the reactor and drain tank cell space coolers, are Circle Seal 424 Model 230B-16 PP, 0.5 - 1 psi. The check valves in lines 830 and 832, supplying.treated water to the fuel and coolant salt pump motors, are Circle Seal Model 230B-8 PP, 0.5 - 1 psi. These special check valves rrevent back flow if the block valves in these water supply lines are closed by detection of radioactivity in the return water stream. The pressure relief valves used in return water lines 837, 846, 841, 847, etc., are Farris Series L475, 1/2-in. size, set at 100 psi. The pressure relief valve in line 855 is identical but set at 20 psi to protect the thermal shield from excessive pressure. The air-operated control valves are described in Part II. 15.3.10.3 Backflow Preventers. - The potable water system is protected from contamination due to reverse flow by a 4-in. backflow preventer in line 890. The cooling tower system is also protected from contamination from the liquid waste system by a similar, but 2-in. pipe size,backflow preventer in line 819. Both units are Beeco Model 6 C, reduced-pressure, backflow pre- venters, as shown in Figure 15.4. The units operate on the principle that two spring-loaded check valves, "A" and "B" in Figure 15.4, (with 8 psi springs) are in series with a spring-loaded diaphragm-operated relief valve, "C", in between. The upstream pressure, "D", acts on one side of the diaphragm and the intermediate pressure, "E", and a 4-psi spring, act on the other. If the supply pressure drops, or thé intermediate pressure increases in a condition tending to create backflow, the diaphragm-operated relief valve opens to discharge the vater to drain. The 4-in. potable water valve, BFP-890-1, relieves water to the building sump. The 2-in. valve in the liquid waste cell, BFP-819, discharges the relief water to the waste tank. The capacities of the two valves at various pressure heads are shown in Figure 15.5. 15.3.10.4 Strainer. - The suction line to the treated water pumps is equipped with a 3-in. Schute and Koerting duplex strainer. The unit consists of two 24-in. strainer baskets with a plug valve to select the strainer in use. While one strainer is in service the other can be removed for cleaning. The unit has a cast iron body with brass strainer baskets. 4 Uneclassified ORNL DWG 64-8845 o o0 o0o0 2 e » - . / Beeco Model 6-C v Reduced Pressure Type Figure 15.4k. Cross Section Backflow Preventers in Water Lines 819 and 890. 95% Né, > 59 02) to eliminate hazards due to combustion of inflameble materials in the cell, such as the oil in the fuel circulating pump lubrication system. The entire primary system is of all-welded construction with all flenged joints legk detected, except at & few less vulnerable locations where sutoclsve fittings are used. Pipe lines which pass through the cell wells to connect to the primary system have check valves and/or eir-oper- ated block valves which are controlled by radiation monitors or pressure switches sensing a rise in cell pressure. The portion of this piping out- side the cell, between the cell wall penetration and the check or block velve, and the valves themselves, are enclosed to provide the required secondary containment. These enclosures are designed to be capable of withstending the same maximum pressure (40 psig) as the reasctor and drain tank cells, except in some speciel cases where containers vented to the ventilation system are used. All service lines penetrating the secondery contsinment, that is, the cell walls, have check valves or air-operated block valves which close on detection of abnormal radioactivity or sbnormglly high cell pressure, or are parts of completely closed piping systems, 17.2 Reactor and Drein Tank Cells During noxmel operation of the reector, all fuel selt will be in equipment or piping contained in the resctor end drain tenk cells. The reactor containment vessel is 24 £t ID x 33 ft in overall height, with hemisphericel bottom and flat top, as described in Section 4.3.1l. The drain tenk cell is rectangular, with inside dimensions of 17 ft 7 in. x 21 £t 2-1/2 in. x 20 £t 6 in. high, and is described in Section 4.3.2. The two cells are interconnected by an open tunnel, operate at the same pressure &t gll times, and will withstand internszl preésures in excess of 4O psig. Both are sealed and operate at 12.7 psie to prevent out- leakage of airborne contaminants. The negative pressure is maintained Q;fi o} 1] 441 by the gas blower in the component cooling system, described in Section 16. | 17.2.1 Cell leak Rate The allowable leskage from the reactor and drain tank cells is taken as 1% of the cell volume per day at the conditions encountered in the posts ulated maximum credible accident. This amounts to 8.2 liters/hr STP at a cell pressure of 40 psig. For the cspillary type flow which occurs through very small openings, the lesk rate 1s a direct function of the cell gbso- lute pressure. At a cell pressure of 12.7 psia, the normal operating pressure, the leak rate equivalent to the maximm allowable is 0.42 scfh. 17.2.2 Cell Atmosphere The cell stmosphere is N, containing less than 5% 0,, the low oxygen content serving to eliminate the hazards of explosions due to possible leakage of 0il from the fuel salt eirculating pump lubricaeting system. Nitrogen is addsd to the cell as needed to mske up for air inleakage. The leak rate into the cells is determined by: (1) observing changes in abso- lute pressure (affier compensating for changes in cell air temperature), (2) observing the change in differential pressure between the cells and a temperature~compensating reference volume located inside the cell, and (3) observing the changes in oxygen coantent of.the cell atmosphere. At the l2.T7 psia normal cell operating pressure, and with a leak rate of 0.42 scfh, the required nittbgen fiufge rate is 1.5 scfh. The nitrogen is normally supplied from,a bank of two cylinders 1ocated in the northwest corner of Building 7503 at the BMO—ft elevation. The nitrogen enters the cell through the bubblers used for msasuring the liquid level in the cell sump, &s mentioned in Section 1h 2._ After the cells haxe been opened for maintenance, approximately 26, 000 scf of nitrogen gas is reqnired to lower the 0, content in the cell to 5% This large volnme of gas will be added through & temporary 1ine from trailer-mounted nitrogen cylinders to the sump jet supply lines. ) 442 17.2.3 Penetrations and Methods of Sealing Piping end wiring penetrations through the cell walls were given careful design study to reduce as much as possible this source of gas leakege. The penetrations through the reactor conteinment vessel wall are listed in Teble 4.1 and those in the drain tenk cell are shown in Teble 4,2, The outside of all process piping entering the cell is welded at the penetrations. | All electricsal leads passing through the cell walls are magnesium~ oxide-filled copper sheaths. The outside of the sheaths are sealed to » the 3/4-in. pipe penetrations by two compression-type fittings, one in- side and one_putside the cell. The ends of the sheaths which terminate inside the ceils are sealed at the disconnect by glass-to-metsl seals. s The ends which terminate outside are sealed by standard mineral-insulated cable-end seals, as manufactured by the Genersl Cable Company. (The seal is formed by compressing a plastic insulsting materisl around the wires.) A1)l thermocouples have Fiberglas insulasted leads in multi~-conductor, sheathed csbles. The outside of the sheaths are sealed to the 3/lU-in, pipe penetrations inside and outside the cell, using soft solder. The ends of the sheaths terminating inside the cells are sealed at the dis- - connect by glass to metal welds. The ends of the cables outside the cells are terminated in epoxy sealed hesders. The headers can be pres- surized to test for lesks. - - | The outside of all instrument pneumatic signel lines and instrument 1 air lines are sealed to the 3/h-in. pipe penetrationes by two compression type fittings, one inside and one outside the cell. Each of these lines contains 2 block valve located near the cell wall, the valves closing antomatically if the cell pressure becomes greater than atmospheric. Methods of sealing certain lines require specilal mention, &s follows: | a. Cell ventilation line 930 contains two 30-in. motor-operated butterfly valves in series, as described in Section 13. These valves are . strictly supervised to assure that they remsin closed during resctor oper- gfi; etion. #" - - 443 b. The component cooling system blowers described in Section 16 are sealed in conteinment tenks to guerd sgainst loss of gas at the shaft seals. | c. The cell evecuastion line 565 conteins & block valve, HCV-565, which automatically closes in event radioactivity is detected in the line by the monitor, RE-565, d. The air supply lines 332 and 342 for the cell sumps contain soft seated check valves. e, Jet discharge lines 333 and 343 from the sumps each contain two block valves in series, FCV-333-A and B, and FCV-343-A end B, which sutomatically close if the cell pressure becomes grester than atmospheric, A 1/2-in. connection is provided between the valves to test them for leak tightness. f. The fuel sampler-enricher system is Interlocked to prevent a direct opening to the atmosphere, e&s described In Bectlion 7. All heliunm supply lines contain soft seated check valves, "5, The steam condensing system used in conjunction with the drain tank heat removal system is a closed loop except for the water supply -lines, which contain soft seated check valves, and the vent, which relieves to the vepor condensing system, to be described subsequently. h. All cooling water lines entering the cell have soft seamed check valves or block valves confrolled by radiation monitors. All lines leaving the cells are provided with block velves controlled by radiation “monitors. '”i, ”The-fuel pufifi lubricating oil system is a closed circulating “-loop. 'Stfict’Supérvisién 1g provided during additions of oil or oil sampling to assure that the conteinment is not violated. | 3 The leek detector ‘system is closed and operates et a higher pressure then in-the reactor process systems. k. Several differentisl-pressure cells and pressure transmitters qjare located-outside'the cells but ere connected to process piping inside through instrument'tubing. The instrument linés are doubly contained. The diaphragm of the DP cell provides primary containment. The instrument ~ cases are vented to an expansion chamber designed for an internal pressure of 50 psig to provide the Sécondary containment, The cases also serve as an atmospheric reference pressure for the transmitters. bbidy 1. All helium supply lines connected to process equipment in- side the cells contgain one or more soft seated check valves. m. The fuel pump bowl off-gas line 522, between the cell wall and the instrument box in the vent house pit, is 1/k-in. pipe contained within & 3/b-in. pipe.162 The drain tank off-gas line 561, between the cell wall and the instrument box is a 1/2-in. pipe enclosed within a ‘1-in, pipe. Lines 522 and 561 share & common 3-in. containment pipe be- tween the instrument box and the valve box attached to the charcozal bed penetration. The charcoal bed pit, instrument box, valve box and the annular spaces around the off-gas pipes, are vented to the containment ventiletion system. The off-gas lines from the charcoal beds have g common block valve, HCV-557C, which closes on detection of radioactivity in the line. n. The coolant salt lines 200 and 201, penetrating the reactor cell well, are part of a closed ecirculating system. They are described in Section 8.5. | The stresses in the relatively thin containment vessel wgll due to the various penetrations were studied and found to be within allowable velues, with the maximum stresses occurring in the nozzles.lE’ 163, 16k * 17.5 Vapor Condensing System An gccldent can be conceived in which hot fuel salt and the water used to cool equipment inside the cells become mixed and generates steam to pressurize the reactor and drain tank cells., (See the Analysis of Hazerds, Part V). A vapor condensing system* is provided to prevent the steam pressure from rising ebove the L0 psig allowsble pressure for the cells, and to retein the non-condensible gases. This equipment, con- sisting primarily of a vertical water tank and a horizontal gas storage tenk, is located about 60 ft from the southeast corner of Building 7503, as shown in PFig. 3.2. The general arrangement is shown schematicelly in Fig. 17.1. * _ The vapor condensing system is sometimes referred to in the MSRE literature as the pressure suppression system, L U % L C PP 40 ft FROM REACTOR BLDG. UNCLASSIFIED ORNL-LR-DWG. 8TI62R2 ELEV. 858 ft — GAS 2.-in.-DIAM. VENT LINE SPECIAL EQUIPMENT ROOM TO FILTERS AND STACK IN REACTOR BLDG. ' FILL GROUND ELEV. - RETENTION FLOOR ELEV. 852 ft 851 ft-6in. TANK I a7 J . . . ,a:,"-,,n — ‘,' [ts vy ELEV. 848 ft - = — =) P E’f{f;}.figw“" ) SECONC10- F1-DIAM. x 66 f1-LONG _ 12-in-DIAM. 3900-ft BURSTING DISK RELIEF LINE N __VACUUM RELIEF VALVE e—————1 +— ~ {00t ————»1 4-in. LINE ELEV. 836 ft X X ~§» TO STACK ] 30 ft 10-ft DIAM. x 23:;‘” HIGH SHALE 1800 > - 1200 £t WATER ELEV. 824 ft 30-in.-DIAM. VENT DUCT FROM REACTOR CELL BUTTERFLY VALVES Fig.17.1. Diagram of MSRE Vapor-Condensing System 5 446 (The method of handling steam that might be generated beneath the reactor cell containment vessel if hot fuel were spilled to the bottom of the cell is discussed in Section 4.3.1.) As shown on the off-gas system and containment ventilation process flowsheet, Fig. 13.2 (ORNL drawing D-AA-A-L0883), and on the layout draw- ing, ORNL D-KK-D-54287, a 12-in. sched-4%0 steel pipe, line 980, branches from the 30-in.-diam cell ventilation pipe in the special equipment room upstream of the two butterfly valves, HCV-930-A and HICV--930-B.165 Inside the special equipment room, line 980 contains s 10-in. rupture disk having a bursting pressure of 20 psi, and in a parallel connection with it, a 3-in. rupture disk with a bursting pressure of 15 psi. 1In relieving at the lower pressure the 3-in,-disk reduces the dynamic impact on the con- densing system when the large disk ruptures. Calculated flows through the 3-in. disk indicates a negligible pressure increase downstream of the 10-in. disk, allowing it to rupture as planned.176 A lLein. hand valve with an extension handle to the operating floor level is piped in parallel with the two rupture disks to permit equalization of the pressure on the disks when the cells are being pressure tested above the normal operating pressure for the disks. With the reactor cell at Lo psig and the vapor condensing system at 30 psig, the estimated mass flow rate in line 980 is 16 1b/.~:~:ec.:L 5 Line 980 continues underground to the vapor condensing tank, VT-1, located east of the ventilation system stack, see plot plan, Fig. 3.2. A 12-in. expansion Jjoint is provided in line 980 to absorb thermal expansions, The vapor condensing tank, or water tank, is a vertical tank about two~thirds full of water, through which gases forced from the reactor cell in a major accident would be bubbled to condense the steam. The tank contains about 1,200 ft3 of water stored at TOOF, or less. The es- timated maximum of 5 x 106 Btu that could be released from the fuel salt in the reactor and drain tank cells would therefore raise the water temper- ature to about 140° .165’ 166 The non-condensible gases are vented to a large gas storage tank. The vertical water tank is 10 ft OD x 23 ft 4 in. high, including the ASME flanged and dished, 1/2-in.-thick, top and bottom heads. The shell is 3/8-in. thick and constructed of SA-300 Class I, A-201, Grade B o+ "4 447 firebox steel.125 There are stiffening rings, l-in. thick x 3 in., lo- cated on the exterior ebout 2 ft 6 in, gpart. 'The tank is designed for 8 peie at 100°F or 63 psia at 300°F. The 12-in. gas inlet pipe in the top head extends 13 £t 8 in. into the tank to sbout 6 ft below the normal vater level, and terminates in a cylindrical screen, 11-7/8-in. OD x 1k in. long, perforated with 7/32-in.-diem holes on 3/8-in. centers, and providing 31% free area, See ORNL drawing D-KK-B-41283. The gas inlet line in the interior of the tank has a 12-in. pipe cross ebout 3 £t gbove the water level to which are connected two 12-in, caest-steel-body check valves. These check valves close when the gas flow is into the tank but 0pen'to return non-condensibles to the reactor cell through line 980 during cooldown sfter en accident. The tenk is filled to the opersting level with potable water through e temporary line or hose, ILiquid level indication is provided by the float opereted instrument, LI-VT~-l. The pressure is indicated by PI-VT-1, end the temperature is measured. There is no bottom drain on the tank, the water being removed by pumping should this be required. The top head of the tenk is provided with an 18-in.-diesm blind flange to serve as a manhole, The 12-in. discharge nozzle for non-condensible gases is also in the top head. The tank is installed vertically with the top gbout 8 £t below the normal grade level of 850 £t and the bottom at an elevation of ebout 819 ft. 4bout 5 ft of additional earth is mounded above the tank to provide biological shielding. The tank is supported end elso held down by a skirt on the bottom hesd bolted to & reinforced concrete pad, 18-in. thick x 1k £t dlam, which also includes a cylindri- cel well, 12-in. thick x 10 £t OD, end ebout 8 £t high. | The non-condensible geses leaving the top of the‘water tank through the 12-in. pipe, line 981, flow through the expansion Joint in the line end to & side nozzle on the ges retention tenk, VI-2. Gases can accumu~- late in this tank, initially at atmospheric pressure, until the pressure falls to & lower level in the reactor cell. The gas then returns to the reactor cell to prevent the pressure from falling below 8.0 psiae. Iine 984, & 2~-in. line with a hand valve (with removable handle) is provided to vent gas to the absolute filters and ventilating system stack. 448 The gas retention tank is 10 ft OD x 66 ft 3-1/2 in. long, in- cluding the two ASME 1/2-in.~thick flanged and dished heads. The shell is 3/8-in. thick, reinforced with l-in.-thick x 3 in. rings located about L £t 7 in. epart. The tank is fabricated of SA-300 Class I, SA-201 Grade B firebox steel and is designed for 8 psis at 100°F and 63 psia &t 300°F. It is anchored into a sand and gravel base by four l-in.-diam galvanized steel tie rods fastened to expanding type earth anchors. The nozzle end of the tank is anchored to a reinforced concrete saddle and pad, roughly 18 in. thick, 12 ft wide, and 6 ft long. The centerline is about 14 ft from the centerline of the vapor condensing tank and the elevation at the bottom is 8% ft. A 1-1/2-in, sched U0 drain pipe, line 982, at the bottom, drains into the vapor condensing tank. See ORNL drawing D-KK-B-41282. The drain tenk condensers, line 338, and the relief valve on the water line from the thermsl shield and fuel pump, line 885, are both vented to the vapor condensing system by joining line 982. (See Section 15.2.) 1 ¥ 10 n ¥, e > N Lo 18. BIOLOGICAL SHIELDING The MSRE building areas are divided into five classifications: (I), those with high radiastion levels that cannot be entered under any circumstances after the reactor has been operated at power, such as the reactor and drain tenk cells; (II), those that can be entered a short time after the fuel salt is drained from the primary circulating system, such as the radiator area; (III), those that can be entered at low reactor power levels, such as the special equipment room; (IV), areas which are habitable at all times; (V), the maintenance control roam, which is the only habitable area on the site when certain large-scale maintenance operations are being performed. These classifications are described in more detail in Section 4.1. The MSRE is designed to permit prolonged 6peration at 10 Mw without exposing personnel to more than the permissible dose* of 100 mrem/week in areas which are entered routinely and have unlimited access.l67 However, it is ORNL policy to 1limit all personnel exposures to a minimum and it is not anticipated that MSRE operators will accumulate 100 mrem/week except in unusual circumstances. The areas which will have unlimited access and which, therefore, might be occupied continuously, will be essentially =at normal background level for the Oak Ridge vicinity. "Hot spots,"” or areas of high local activity, are generally located near the reactor or drain tank cell penetrations and are in areas which ~have only limited access, Such'as the coolant cell. The overall activity in the coolant cell, however, does not exceed 100 mr/hr. The blower house "is also a limited access area, with a radiation level of about 20 mr/hr near the No. 4 blower. Although the special equipment room is classified a limited access area, the radiation field does not exceed about 10 mr/hr. The south electric service area, another limited access portion of the ‘building, has & generally higher radiation level of 200 mr/hr, with some "hot ' spots" fiear'the:penetrations. A1l the above estimates of activity levels are based on operation of the reactor at the 10-Mw power level. *Based on 40-hr work week and that 1 roentgen equals 1 rem for gamma radiation in soft body tissue. 450 The intensity of the radiation in the auxiliary cells is less de- pendent upon the reactor power level than upon the nature of the materisls present in the cells. These conditions change from time to time, but in general, all the cells have limited access. When the reactor is subcritical, all areas except the reactor, drain tank and fuel processing cells, may be entered a few minutes after the reactor is shut down. In general, access can be on an unlimited basis except where "hot spots" may exist.l68 For example, if the coolant salt were drained from that circulating system, two 4-in.-diam holes would be left through the reactor shielding, one of which "looks" directly at the fuel pump bowl, and could cause a localized beam in the coolant cell of several r/hr. Entry to such areas and work in the areas will be monitored and additional shielding provided as required. 18.1 General Description This section provides only a summary description of the biological shielding. The general construction of the cells and other aress is de- scribed in more detail in Section 4 of this Part I of the design report. The calculations necessary to confirm the adequacy of the shielding are presented in Section 13 of the nuclear analysis portion of the report, Part T11.70% 1095 170 me 4hic1ging needed for the fuel handling and processing system is covered in Part VII. Shielding required during maintenance procedures is described in Part X. The reactor vessel is surrounded, except for a 2-ft-diam opening at the top, by a 16-in.-thick iron and water thermal shield. This is located within the reactor cell containment vessel which, in turn, sits within a shield tank to provide a 3-ft-wide annular space which is filled with - magnetite sand and light water. The shield tank-is surrounded by a cylindrical monolithic concrete wall 21 in. thick. A portion of this wall fécing the south electric service area and another portion facing the coolant area are left out in order to make the penetrations accessible. Barytes concrete block walls are provided to shield accessible areas ad- Jacent to the coolant cell. The additional shielding is not necessary «? s y 8 32 451 in the electric service area in that there is a minimum of 2 £t of con- crete between it and any accessible area. The top of the reactor cell is constructed of a 3-1/2-ft-thick layer of barytes concrete blocks covered with 3-1/2-ft-thick blocks of ordinary concrete. The joints between the upper and lower layer of blocks are staggered. High-density shielding blocks are temporarily stacked above this as required. | The pipe penetrations through the reactor and drain tank cell walls pass through sleeves which are filled with magnetite concrete grout or magnetite sand and water. Where possible, these lines have an offset bend. The penetration of the 30-in-diam exhaust line through the bottom - hemisphere of the containment vessel reguired special treatment because of the size of the opening. A shadow ghield of a 9-in. thickness of steel ig provided in front of the opening inside the cell and a 12-in.- thick wall of stacked block is erected outside the cell at the foot of the ramp to the coolant cell. The top and sides of the coolant and coolant drain tank cells pro- vide at least 24 in. of concrete shielding as protection against activity induced in the coolant salt while the reactor is producing power. The large openings provided between the coolant cell and the blower house for the cooling air supply to the radiator, however, make: it difficult to shield the blower house from this induced activity. A 12-in. wall of barytes blocks is stacked across the opening between the reactor cell and the radiator duct to shield the blower house area from the coolant salt lines. | The drain tank cell has a minimum thickness of 3 ft for the magnetite concrete walls facing accessible areas. The top of the cell consists of a layer of Y -ft-thick ordinary concrete blocks covered by & layer of '3-1/2?ft-thick ordinary concrete blocks. The joints between the blocks are staggered. The pipe lines penetrating the cell walls have offsets, +the smaller ones being cast into the walls. Shield plugs are provided for the larger penetrations. The l/2-in. off-gas line from the reactor cell, line 524, is shielded by 4 in. of lead as it passes through the coolant drain tank ~d4 452 cell. Barytes concrete blocks are stacked to a thickness of 5 ft above &-j the line in the vent house, and 17-in.~-thick steel plate is provided above the line between the vent house and the charcoal beds.l7l The charcoal beds are submerged in water and the pit is covered with two 18-in.-thick by 10-ft-diam barytes concrete blocks. Barytes blocks will be stacked on the cover if additional shielding is required. The walls of the filter pit for the containment ventilation system are 12 in. thick and the roof plugs for the pit are 18 in. thick. The thicknesses of the walls and tops of the auxiliary cells is given in Table 4.3. Additional shielding is provided by stacked blocks on the west side of the fuel processing and the decontamination cells. ' 453 19. ELECTRICAL SERVICES The MSRE €lectricel services system furnishes power for process pumps, equipment heaters, instrumentation, nuclear control and safety circuits, and various esuxiliery equipment., Power is also provided for the bullding cranes, repair'shops, end general building lighting, venti- letion and eir conditioning. ' The MSRE installation mekes use of the relstively extensive electri- cal fecilities that were installed for the ARE and ART operations in the Building 7503 area. This existing equipment was modified and supplemented, a8 required. The installed electrical cagpacity of MSRE process equipment, ex- cluding generel building services, is about 2,000 kw. The normsl operating load 1is approximately 1,100 kw. Pover is supplied from the Tennessee Valley Authority distribution system through two parallel 13.8 kv feeder lines. In the event of failure of the normal power supply from the TVA system, batteries provide the L8-v DC power for the reactor control end safety circuits and also 250-v DC power to drive a 25-kw motor-generator set to supply AC power to other in- struments and controls, the’sémpler-enricher station, the control-rod drives, and the lubrication systems for the salt circulating pumps. These batteries serve until the emergency diesel-generstor sets can be started and loaded, & procedure normally requiring a maximum of 5 to 10 minutes.* In event none of the diesel units can be started, battery capacities are more then ample to meintain control of the resctor and to drain the fuel selt to the drain tenks without damage to the system.‘ The three emergency diesel-generaxor sets have a»combined capacity of 900 v AC. This emergency AC power cen drive the 3-kw, L8-v, DC motor- generator set normally supplying the reactor control and safety.éircuits. During the emergency period, the lube oil systems, control-rod drives, “¥The time aveilsble for starting the emergency diesel-generator units without draining the reactor is.limited by the thaw time of the freeze valve on the reactor drein line 103 and by the pressure end temperature rise in the reactor containment vessel. A period of about 10 min is esti- mated to be available. 454 and other important AC equipment mentioned above, can continue to re- ceive power from the battery-driven 25-kw motor-generator set (for at least two,hours), or they may take power directly from the diesel-driven genergtors, With the three emergency diesels in operstion the reactor can operate at the heat-loss power level indefinitely until normal electric power can be restored. 19.1 General Description A simplified one-line diagram of the electrical supply and dis- tribution system for the MSRE is shown in Fig. 19.1. Reference numbers on this diagram are keyed to the descriptive material in the following sections. The MSRE is supplied with electric power from the 15k-kv Tennessee Valley Authority system through a substation located just north of the X-10 ares (see Fig. 3.4). Either of two 13.8-kv transmission lines from the substation, ORNL circuit 234 or 294, serve the Building 7503 area end ere interconnected through interlocked motor operated switches at the MSRE slte so that circuit 299 can serve as an alternative to circuit 234k, The normel supply is through ORNL circuit 23L. The feeders supply & bank of three 250-kva, 13.8-kv to U480-v, trans formers located on the east side of Building 7503 to provide power for general building services. The feeder power is 8lso connected to a new 1,500-kva, 13.8-kv to 480-v, trensformer located on the west side of the building to serve the MSRE process equipment load. The process equipment distribution system is shown schematically in Fig. 19.2. (ORNL drawing D-KK-C-41152) The 1,500-kvs substation feeds a TVA" switchgear bus which supplies power through circuit bregkers to three generator*® switchgear busses, two TVA motor-control centers, two 250-hp radiator blower motors, and to the 200~hp motor for the 250-v DC motor-generator set. The two TVA motor control centers supply power to *Throfighout the electrical service system reference literature and drawings, the normel source of electric power has been designated "TVA," as contrasted to the emergency source, which has been called "generstor." il vy o ™ S UNCLASSIFIED | o INTERLOCK - . ORNL-DWG. 84-6746 13.8 KV — Po— o - 13.8KV CKT 234 1 I _ oK 294 , _ | : SWITCH SWITCH HFIR 129 229 . - 1500 KVA 13.8 KV/480V 2V ieooA e e TO BUILDING ' ' SERVICES SEE 19. o TVA SWITCH GEAR BUS ' I . -~ , K SEE 19.4.1 d 600A )T , 600A )S 300A )P 300A)a GOOA)X soon)z g ' € < GENERATOR #5 GENERATOR #4 - : GENERATOR # 3 X " SWITCH GEAR ' ? GENERATOR - &I’ SEE 194.2 600A JA-4 [ 600A )A2 . 600A }A-3 ' GOOAI)A-l 600A )A-5 ¢ I ] + ¢ _ I GENERATOR BUS # 3 r - SWITCH GEAR BUS # 3 € , 2254 ) AA 225A)88 350A )cc )Dn 600A)F 90A)D IOOA)E 90A )X 600A )L 200A )u 100A JH 600A ) REVERSE o q g . \ POWER 250V SPARE 250V TRIP BI‘I"JTERY I00KVA i 600A SeE 1981 MM-G-2 A3 MCC-G51 (72) &) (2) |Mece (12) SEE 19.4.2 LIGHTING 400 A SEE i9.42 G-5-88B SEE19.4.2 FP GP-2 cP GP- 400 A ] 250V-DC DISTRIBUTION PANEL AUTOTRANSFORMER "~ [mccoe , q 0—06 o— . . 64-31 [SEEI9.42 S0A PROCESS ) POWER. PANEL : »2 30A 60A I3A 400A ) 4-3¢ 1$-3¢ 3.8 KV MG-4 CONVERTER| |CONVERTER 250V-DC D.C. REMOTE _ o I RS ) ) LIGHT Bc AC INSTRUMENT INSTRUMENT 0G # 5 POWER POWER 250V 120V~ PANEL # 1 PANEL # 3 AUX. PANEL afl:v_ ' SAMPLER 8 : : CONTROL ROD FOP-2 copP-2 DRIVE FIG.19.1 SIMPLIFIED ONE-LINE DIAGRAM OF ELECTRICAL SUPPLY SYSTEM GGy b G pr— - II‘f’fggfj - - -\) \5‘ a’f:‘/:—y: ‘S‘;.’:‘E: ¥ L AerA 5 ) u/ P (R&EN) ' "&’ t A FOA He b /u 4. lrr i 1 SrEL R /4 .“'”K-"_-‘—z T-tT | - j . Gr AL 2N ) ) QI—L_— t T Lot ER I NOBIIRL SUPFLY) - ~§,tE O rad ZXISTING Dr&2els LAIBTING .' 3. 8 XV OVELNERD I ACNL TR T34 i, | I S | FBpng] ngriigie quom_fiu_!!u‘_)_J? 456 e ‘ _ Unclassified o m— e — _——— e e e - et ———— 9 L #rre ORNL DWG 64-8847 Wt aresee - 30 ww, — “ 4 Ay I Diksel Joouw, z CoNERRTOR - /D00 AN, .- Ptfiorn hw.r e T e GEAFRATORS SO NI, 325 K¥A, l (van Riorra, 480y A “ gav. j | pew} T 7fod Sos. 4 Cla0 MM Fin @ - " e toatca 2:25C. |, - (s G322 M, 284 C Vo \Tc‘ot;:‘“r::l ‘ Lecenvo . 180 N . BT T - — — N ‘ TZouchr 4. 'c'~’q~‘ -3 0""/ raoy S i soom, + M Cowracron - F3R. 480K, n) Y. Core ¢ Egelidey, G 'S I»mwunc aU.f”"f’”‘ S, -:.rume aw ol T T T T T T S siemeirmed 1€ Cowseoc THsyriatrrR. [ E-2anmMEm Pyn 66’ l , fi Ian s J'n,nws.mo Jd.rMJ Saw A IIIIN S ERR, Bu, fud # Mors ki me JEFl p - | / % poomen 82V t [ I °1 | 1 ! s ) L) r0g) 1o e Lazima n#) Lumcorr seenwek - T8Anr reret o wul I §~L % 7Ty y . - L — - _t - ‘ -~ - - - - wa y. ‘ N ; ) - | ™~ | L, ¥ O WY 8 S e ¥ ARRING S ONRT. § Clew, T o £l ; ; ; U7V worcarss srur tovim re e Ruvseo . ': ."1:‘ o 8 ;t,ll i s q o a0t £y Biit AF INOKATED X ‘ ) l. - .4 = ? 7 y . | l | f\ v.;‘ w o~ S 3o i s : — TEMM, BOX &Y ORNL, D INOICATES NEw &QuUIA T4 86 AN IED gcuny o 1% Y 9 A (Y omme l M ‘_’.llfl‘ I ‘ R "l . Y aRuL, - 3 ¥ -— = = — - A R N, wirarine $ 'T‘f INOICATES [5Cr 08 8Us REMOVED_QITWU EN Arer pofn h b‘*la . & ' e, > spasr S §. X ; /nvorcart:___g_g K METIR 2N I1TEN CTRY A3 NOred VI &3 : s 2. 978, Ous._ Onnc d7j4s ) MNEY M2 TRANS. == ; [$] LIRE T REVERIING STHRTER LI, ON FQUIP, &8-i-0- le | "‘ OO0 A ‘4' gz Consycren Sl d& JEONOUIS JI2 8 7l'lvfl XIS, | L Lerease Pomen j ?iltla«wrfl £A7TE) s ,,,,,m. T - ) ! rRrp emrsglfformmn .L_M. CONOYCIIAT TAYHLLER THAN T JHALL ® Pwi. B, 8CT. AN 1-0-2, ‘ " : &€ rvsy raw S0 7er 0 o : CONQUTIRNT LARSEL FaAN DL sheid 58T mg -2 - l A2ra £L 125 owwy ‘ _'O_©-°-— &7, 4 - KLl oo, T4 1oa Fa waveri LAc, oc__ P c‘olaaéoc.r Zdzg fi;y "_f fi fiw ¥oA., 47 S AW —_— . — ———_— — — 250D.C oursur ¥ 4 I - - fforecr ?‘znr NEwW | e e | ) NoTa: Pwi. &8 1.2-3 16LOCATED in PNL. B8cY. o AND 13 PRIZENTLY 10, BF-}-0-1. S22 PRuc-20124 P ot O.C BaA.TRIP 28 KVA BAT, REscTOR oA, _J ronen £ 2L LArR PAAIN TANR T.m. Y OBNL 2504 0.C. ARNEL LS KYA TOANGP. FILL LINKE HEATER S u-108 Whonover 8 minwiscturer's neme or soivleg mumber ~ 4 lndionied on the drawings, ™0 spproved squel ey ~ b nbaritvted unlas ethorwise wted $ " 5 av x| 2 < ‘ : r .._I oy . id gl 3 | J g Ul ”“: ? : |:‘"il e | o OIICONNECT Jppy t (™ ol N v . INY aran s e T A | € J_ ® T8 TRNIELR 3N 7 TN 5 wisdy Ly tn _’%% " | i RRLVEILL FE N ’ : ~l§ il Wad Erx-dfamwpyicl $ - D are 5. 4 red diyeson ' L oHd’s A : ‘' | A . Y 1 £ wareh, l'c-, "?"' prem v 'f ‘ 70. TRANSFIR LELL JAIT: :'V :.::,T.. i . fl'Effl'rnw KJ) :: ‘i.;";z‘p\wvrr €| eae. oy :L e CONYERIEAL - ALayNe 38-¢ = « = 427 3ATT j INST. PowaA Luo ) (NBw) . NL.#3 , KON, . Fig. 19.2. Process Equipm?nt Electrical Distribution System. i | ¥ b} % e b oA 54 £ SO i £ et Ariiimnsn 1% e s - e . et 2L v s o o el gt b St S 1 1 1 WAt 0 Wk b 8 i 1 0 g R 8 T8 S T8 L S g 1 et 7 iyt st b e 457 the less critical process heater distribution centers and to a few non- critical smaller motors. The three generator switchgear busses are normally fed from the TVA system but each has its own diesel-driven, 300-kw generator* to supply emergency power. Generator No. 5 supplies one heater distribution panel and two motor‘control centers which provide power to the heater distri- * Generator No. 3 bution panels for the more critical process heamers.% and generator No. 4 switchgear busses furnish power directly, or through motor-control centers, to all critical motorized equipment and to some instrfimentation. ‘Where reactor_proceés equipment is installed in dupli- cate, each unit is supplied from a different generastor bus to provide greater reli&bility-of7emérgency 0pergtion. Thé process distribution system includes the aforementioned UB8-v DC motor-generator set which supplies power to the important regctor control and safety éircuits. This direct-curfent system orerates from a battery supply during & failure of the normal power source until either diesel No. 3 or No. 4 can be started. | | The building services distribution system is shown schematically in Fig. 19.3. 'This system supplies.power for building andvgrounds lighting, for heating, ventilating and air conditioning, and for maintenance services, such as cranes, welding, etc. The power is supplied from two main dis- tribution panels and from various lighting panels located throughout the building. Part of the building lighting load can be transferred_to the generator No. 3 switchgear bus for émergency lighting in event of failure of the normal supply from the TVA system. ¥The No. 5 diesel-generator unit has a nameplate rating of 1,200 kw, but has a continuous duty output of 300 kw due to the limited output of the diesel engine. See Section 19.3. *¥Across-the-1line motor starter contactors and circuit breakers in the motor control centers originally installed for the ART are utilized ex- tensively in various MSRE circuits and are termed "motor control centers" in the MSRE literature and on drawings even though a particular center may be controlling a heater, for example, rather than a motor. T 458 rexcin®y /3. agv(rm) SUPRLY 28KV g Gon L2/o suen H.0. Conrrer & -J00 McH | AANUAL AYAIN BREACEL —————am Fo8 DidraiAuTIoN Sr. Y (o soee— LAVO MM I Joo mear r AN BREANTE Go0A ) mp pisrarBurien Pws 2. _ _ Unclassified . st50k A ORNL DWG 64-8848 iy G e Jm-er/am An—-—r"‘ A QUITe/8UTION PANEL Mol (480v, .m, GOy 750A.) - ‘ ’l’fil) ' G-d1oMem T‘lf”@ ;i' ~SaOACAH dus Q.rrcuurmw Aavee m.f (“'OM, I, GO, JOTA, ) e |7 R [ s J 1% 1 oo | “ N ’ ’ : J . I‘” "J 'u .,, "‘ W04) 4e0d) 400A) 1004) s04.) “A.) 164.) m) 2 ) o) Zea ) . fo0) JoA) seeA) /m) ) mn.) 7oA ) ) ”a. ) w04 ) .uu m s i d I 12 da!._fl sot 2% s | 7% 142¢ s I L{! SArRS Savae Lraes Saree N & ¥ M Rl Iver wrasiece; - l-z-a_‘_'su I *&I X $0m. 39 Lreeer w0 s { o2 3 o4 | (1 MR COINT ARV fifi %|m verene, ° — B ] ECiET el Avea L% foon s0a 3y o 9 :fi Q . - 4 8 FReL TR DT coreo ot Zécepracies % wnTl | dren g0t ge gfi_‘&_ " o e o JrOViCE AdeA N ShefG zrg‘ay £5 ’ » ' ¥ ‘é’ Lholtek /.cam:gg‘g(' ) W g% i‘ ] o - X ¥ 2 NS <& \;k Y NV E . 0 £ousp, Qearoreo E‘islfi‘:;@mc o ;Z:‘:r Aovan _rmn%szfv?"flv Faay &iere, ¥ Lo, Ve on 2ir Conres crk. e poirity &“ F/%yy_' v 24 ¢ & ‘f‘;“ . I'Y/0 ¢ 1%/ ‘ - 100 ACY . ‘ o0 OLITRIGUTIEN PPNEL Mo LA (RV/E08V, IN, GO, 7504.) QUTRIIVTIon CONEL TAL™ (100/208¥, 4N, 60 5., $004.) B~ % 7 e |7 |« . [ T Jv Jv Jv Je |o | a@ . oA, s04.) s ) aea) sooa) A ) amot) mod) s0s) oA man) merl) mod) soohl) 8 S g1 10| g o ' y | | | I I | I d 714 . 4 - .g°, oy Last 1 IANEE IAEE LAy JAver IMIAE sAeRs £ i vl | | Aw? ro ¥ { & Qowren| |Cuezemt } I & Lae [ 23 | . f s l ’ | . | & T T4 42w = | | ! ‘ ; l | / TRINIE | (" o7 hoa s thuer ' g ' - 9 e gl oS! '”‘:’%:;}L; zJL:cmr_f.« Jer e QezerF s G : “1- Lok Conr Sav Ome " ek CA3T @/A Y L_s=z % @ ,_7_"1 I 2 e BT 87 46T L67 LET. . y . e 25¢ oL A ONg. % fi% ! ” £ . s § » . L - » Q - (%{‘”” :; _‘ —-_;- 0o, e A, reed /904, ea 120 A. Py - 2o L £ 2 = Covnmerirot ro/own| (2420, @’_4{{_414 iwrear| | Vegeear| (ia2eed | |i2adroer) eirear veust e ew| |t em rrr mea| | wrsund | Yrer #e| lews-gard | |casmna] |r8smer . 3 %yre ] gon 2B.7°C ro vewr WOTIR W JUMP AT 3%,1% re Roaw 3¢ 50'4 £0 ~I”£ Fig. 19.3. Building . \_’_1!4'.0 AN, TPRATE £ 190 Trac 46/ /e B0Y PIOF YENT KRN ATIT RS Services Electrical Distribution s = e Qasei #w, LPECK £y System. 1 459 19.2 Transmission Lines and Substations Electrical power is supplied to the MSRE site by two 13.8-kv over- head feeder lines from the ORNL substation located just north of the main X-10 area, see Fig. 3.4. These are designated ORNL circuits 234 and 290L. The preferred supply arrangement is through circuit 234, through the motor- operated disconnect switch, M-1. The elternate arrangement is through circuit 294 and the motor-operated disconnect switch M-2. These two switches are interlocked to prevent both switches from being closed at the seme time. The switch, M-1, has an opening delay timer which allows a 1 to 10 sec loss of power on circuit 234 before the switch opens, then the switch M-2 entomatically closes if there is supply voltage on circuit 29k, The control circuit for M-2 will also prevent the switch from closing if there is an electrical fault in the Building 7503 érea. The control power for the breskers M-l and M-2 is from the Bullding 7503 area 250-v DC system. The switches can be closed from the remote pushbutton station in the MSRE auxiliary control room or manuelly et the switch poles C and D located north of the building. The process power substation is located west of Building 7505 and con- sists of an oil filled, 1,500-kva, 13.8-kv/UB0-v, 3-phase, 60-cycle, 3-wire, delta-connected Uptgroff trensformer with & meximum impedence of 5.75%. The 13.8 kv supply enters the substation through a high voltage, fused cut- out disconnect switch. The 480-v transformer output enters the switch house through twelve 750 mem (0.998-in. diem) cables laeid in underground conduit, through a 1,600-amp breaker, R, to connect to the TVA switchgear bus. ' The bullding service substation is located to the east of Building 7503 end is supplied through & discomnect switch. The substation consists of three 250 kva, single~phase transformers connected delta-delta to re- duce the 13.8-kv supply to 480-v, 3-phase, €0-cycle power. The transformer output is brought into the building through nine 500 mem (0.81k-in. diem) underground cables. Six cables (two per phase) lead to the 600-amp main * mem = thousand circular mils. 460 circuit breaker for distribution panel No. 1 and the other three lead to the 600-amp distribution panel No. 2. These circuit breakers are located on the wall of the main building at column D-UI (see Fig. h.lh) at the 8L40-ft elevation. 19.3 Emergency Diesel-Generators Of the five diesel-generator units initially installed in the generator house for the ART project, two were removed for other duty and three remain for use in the MSRE. These units, numbered 3, 4 and 5, have a continuous capacity of 300 kw each, as explained below. Individual busses were selected for distribution of the power from the generators to the centers on the basis of calculations of the size and nature of the MSRE emergency electrical loads, the sizes of the existing switchgear, and the characteristics of the diesel-generator uni‘t.s.h2 A ground detector alarm is provided for each bus. The three diesel-generator units can be operated from control panels located in the switch house. These panels have the necessary switches, controls, and indicating meters to adjust the generator output voltage and frequency and the synchronizing equipment for paralleling generators No. 3 and L4 with the TVA system. All three units can be started remotely from panels DFM 3, DPM L4, and DPM 5 in the auxiliary control room. These panels also include remote switches to open circuit breakers Al and A2 to isolate busses 3, 4, and 5 from the TVA system and to close breskers A3, AL, and A5 to connect the generators to their respective busses. The remote panels elso include diesel annunciator alarms, voltmeters and ammeters for the generator outputs, and a voltmeter for the TVA system power. 19.3.1 Diesel-Generator Units No. 3 and No. 4 These idential machines are Allis-Chalmers Buda unitis, Model 8DC sG-2505.17% 450 at 1,200 rpm. A 10% overload can be carried for a maximum of four hours, which must be followed by a cooling period of at least two hours The engine is rated at an availgble brake horsepower of at no more than the rated load. The engines are started by a battery 461 bank for each unit, Annuncistors are provided to sound elarms on high cooling weter temperature, high oil temperature, low oll pressure and low fuel level. The generator is a direct connected Electric Machinery Model DCSG-300-A3E, rated at 300 kw, 375 kva, 480 v at 0.8 power factor, for continuoue service. Each generstor frame is equivalent to a 500-kw, 625-kve machine, however, this oversizing having been provided to com- pensate for the reactence load which would have been imposed by starting the large motor involved in the ART operations. Although the generator 1s constructed to AIEE end NEMA standards for an intermittent overload of 50%, the meximum overloed is limited to 10% by the capacity of the driving engines. (These overload values do not apply to rapid load changes due to motor startings.) Synchronizing equipment enables diesel-generator unit No. 3 or No. 4 to operate in parallel with the TVA power supply so that the loads can be trensferred from the generators back to the TVA system without interrupting reactor operstion. However, both units must not be oper- gted in parallel with the TVA system at the same time. This would expose the motor cqntrol center busses to the combined ceapacities of both gener- ators and the TVA system and would greatly exceed the current carrying capacity of the busses in event of a dead short in & connected load. The individual busses for generstors No. 3 end L supply all motors which need emergency power. Since the voltage drop in a generator bus - is critical when starting motors, starting currents have been limited to | 5ho amps 80 that the generator voltege will not fall below 80% of the . ipitial_value. ‘ 19.3.2 Diesel-Generator Unit No: 5 The diesel engine for this unit is & Caterpillar Model D-397. It 15 rated et 455 bhp at full loed end at 1,200 rpm. It may be overlosded 15% for two hours, which mst be followed by & cooling period of at least two hours &t no more then rated 1oad. The engine is started by a com- pressed air motor supplied by a nearby air receiver and compressor. The receiver stores sufficient air for five l0-sec starts. The compressor *Eqnivalent to a T5-hp motor with a starting current 5.5 times full load rating. 462 can recharge the receilver in 20 to 30 min following one lO-sec start. An annunciator sounds an alarm on high cooling water temperature, high oil temperature, low oil pressure, low fuel level, and low starting air pressure. The generator was manufactured by Electrical Machinery, is rated at 1,000 kw, 1,250 kva, and is direct connected to opersate at 1,200 rpm. For continuous loading it is rated at 300 kw at 0.8 power factor. As pre- viously mentioned, the oversized generator was provided to compensate for the reactance in starting large motors involved in the ART. Although this generator was also built to conform to the AIEE and NEMA standards for in- termittent losds of 150%, the maximm load is limited to 115% by the ca- pacity of the driving engine. 19.% Process Electrical Circuits 19.4,1 Switchgear Equipment Except as otherwise indicated, the switchgear equipment is located in the switch house, as shown in Fig. 19.4. The equipment was manufactured by Westinghouse Electric Corporation. The busses are rated at 1,600 amps, 480 v, and have a 50,000-zmp short circuit carrying capacity. The R, P, Q, and Al circult breakers are Westinghouse Type DB 50, with a 1,600-amp frame, 50,000-amp asymmetrical, at 600-v, short circuit capacity.* The remsining circuit breekers are Westinghouse Type DB 25, with 600-amp frame, 25,000 amp asymmetrical at 600 v.** See Table 19.1 for other data on switchgesr busses snd breskers. 19.4,1.1 TVA Switchgear Bus snd Current-Limiting Reactor. The TVA switchgear bus, including breaker R in the supply line from the substation, is located in panels 2 through 5 on the south side of the switch house, as shown in Fig. 19.4. There are ten circuits connected to the bus, as in- dicated in Fig. 19.2, The first two 300-amp breskers, P and Q, supply power to the 250-hp motors of the blowers which supply cooling air to the *60,000 emp asymmetrical at 480 v. *¥%35,000 emp asymmetrical at 480 v, et a4 o oo i = L e b R s v 463 UNCLASSIFIED ORNL-DWG. 64-6747 N eaax _ MCC T-1 MCC G-3 MCC T-2 125 KW AC—DC-MG IE1|E2“E3|E4|E5IE6|E7||E8|E9| - 25 KW Nit. |[MCC G5-2 s1 | 65 DC-AC-MG N10 s2 N9 s3 ‘ TVA N8 s4 S N7 . S5 1500 KVA MCC G4 SWITCHGEAR | 8 N5 $7 |CONTROL N4 S8 L e o o e o e G3 N3 $9 N2 s10 | G4 MCC G5 N1 s11 | 6 MAINS | ] | 2PL o] B ~~svyNcHrRONIZING DIESEL CONTROL PANEL | b FIG.19.4 LOCATION OF EQUIPMENT IN SWITCH HOUSE | Table 19.1. Switchgear Bus end Breaker Data L6 Breaker | ( Tap and Termination Size Operation Location Ceble, No. | Starter Potential Current i Instrument Locetion Interlocking Action Remarks Breaker (amps) ~and Size | Location | Transformer Transfomefr Voltmeter | Ammeter| Wattmeter | -1 ™A Switchgear Bus | R TVA Bus 1600 Elec op sw. ||S-5, Local | 12 No.750 - - - \ - - - - Supply from substation. _ mem i _ P MB-1 300 | Elec op sw. {|S=5, NCR 5 No.350 MB-4 - 300/5 amfia - Local - - Bresker-starter combination mem ' ! Q MB-3 300 | Elec op sw. |{|S-5, MCR 3 No.350 MB-k4 3¢, 480/120-v | 300/5 ampis DPM-L Local - - Bresker-starter combination. mexn g Voltage is TVA supply. 5 Swg Bus 3 | 600 | Elec op sw. ||S-3, Local | 6 No.500 - - - - - - Close before A-1 In series with A-l. mem | . T Swg Bus &4 600 Elec op sw ||S-3, Local | 6 No.500 - - - - - - Close before A-2 In series with A-2. ' ) mem i z Swg Bus 5 600 | Elec op sw ||S-2, Local | 6 No.500 - - 600/5 m’és - . DPI-DEMS | Close if A-4 is mem ; open. X MCC T-1 600 | Manual S-2 6 No.500 - 2g, 480/120-v 600/5 amps - - DPI - PT or main bus for X and Y mem : wattmeters. Y MCC T-2 600 | Manusl S-2 6 No.500 - - 600/5 emps - - DP2 - mem | U Spare - §-3 - - - 200/5 aups - Local - - v Spare - 5=3 - - - 200/5 ampis - Local - - Switchgear Bus No. 5 | 'i AR MCC 5-2 350 | Elec op sw |/S-1, MCR 3 No.500 - - 400/5 emps - - DPI Under voltage trip. mem \ BB HDP G5-BB 205 | Elec op sw ||S-1, Local | 3 No.300 - - 250/5 emps - - DPI - mem 7 CcC MCC 5-1 350 Elec op sw ||S-1, MCR 3 No.500 - - 400/5 am;}»s - - DPI - mem | DD - - - S-1 - - - - | - - - - : i . A-L From DG-5 600 Elec op sw ||S-11, MCR 6 No.300 - - 800/5 eunfis DP-8/DFPM-5 DP-5 |(DP5-DPM5 Close if Z is open. Reverse current trip. mem ,f Note: See Appendix for explanation of abbreviations. 465 radistor. The remaining eight circuits are connected to the bus through a current limiting reasctor. This inductance coil protects the busses and circuit breskers in event of dead shorts in the feeder circults by creating a back electromotive force to limit the short cireuit current. There are three Westinghouse Type MSP - 6R2207 reactors, one for each phase, rated et 16.6 kva, single-phase, 1,200-amp, 13.8 voltage.drop; and L480-v line. TwO bf'the eight circuits éupply the TVA motor control centers T-1 and T-2 through the circuit breakers X and Y. Three circuits supply the generator switchgear busses through breskers S, T and Z. Another circuit provides power for'the 250-v D¢ mbtor-génerator set through bresker W. Circuits U and V are spares. See ova drawing D-KK-C-41175. ' | 19.4.1.2 pwitchgear Bus No. 3. This bus is located in panels 8 and "9 on the south side of the switch house, as indicated in Fig. 19.4, and is normally supplied with power from breaker S on the TVA bus through. breaker - Al located at panel 8. This bus has an alternate, emergency power supply through circuit bxeaker AS, from the 300-kw diesel-generator set No. 3. Switchgear bus No. 3 supplies the following equipment: ‘the;coolaht'cir— culating pump (breaker K), the component cooling gas blower No. 1 (breaker H), the 100-kva emergency lighting trsnsformer (breaker M), the motor-control center G~3 (breaker L), end the spare circuit breskers G, J and N. Data for the switchgear bus No. > circuits are given in Table 19.2. (Also, see ORNL drawing D-KK-C-41176.) 19.4.1.3 Switchgear Bus No. 4. Bus No. 4 is located in panel 10 on the south side of the switch house, see Fig. 19. Lk, The bus is normally supplied with power from the TVA system through breaker T and through breaker A2 on the No. L bus. The bus is also provided with emergency power through bresker A3, connecting it to the diesel-generator set No. L. Switchgear bus No. 4 supplies power to the fuel circulating pump (breaker D), component cooling gas blower No. 2 (breaker E), and the motor-control center G-4 (breaker F). (See ORNL drawing D-KK-C-k1176.) 19.4,1.4 Switchgear Bus No. 5. The generator No. 5 switchgear bus is located in the first panel on the south side of the switch house and is normally supplied with power from the TVA system through breaker Z. This bus is also supplied with emergency power from the diesel-generator unit No. 5 through breaker A4. The bus supplies power to the heater Table 19.2. Connections to Switchgear Bus No , Bresker L | Tap and | Termination Size Operation |Locatign |Cable, No.| Starter Potential Current - In Bresgker | ' (amps) and Slize Location Transformer Trensformer (Voltm Switchgear Bus No. 3 A-1l Bus 3 600 Elee op sw.|S-9, DH-3,|6 No.500 - og,480/120-v | 3@, 600/5 emp| DPL/D | | DPM mem . A5 Bus 3 600 | FElee op sw.|S-11,DH-3,|6 No. 250 - o9,480/120-v | 3¢, 600/5 emp| DP3/D H CCP-1 1100 Elec op sw.|S-9, ME-2 |3 No.1/0 MB-2 - of, 150/5 emp - K P 9 | Hec op aw.|5-8, Mi6 |3 No.1/0 | MB6 - o, 100/5 emp| - L McC-G-3 | 600 Manual |S-8 | |6 No.350 - 3¢,1480/120-v - - | mem S = M Lighting | 200 Manual | S-8 13 No.1/0 - - X-fmr | | N Spare | -8 J - Spare S-90 G Spare 59 | 5 Switchgear Bus No. 4 A2 Bus 4 600 | Hlec op ew.|8-10 6 No.500 - | 24, u80/120-v | 24, 600/5 emp| DPI/I - DPM-b mem | ’ A-3 Bus 4 600 | Elec op sw.|S-11, 6 No. 250 - of, 480/120-v | 3@, 600/5 emp| DPL/] DPM-lt mem ‘ | D Fuel Pump| 90 Elec op sv. s-J:g, 3 FNo. 1/0 MB-8 - of, 100/5 emp - MB E CCP-2 100 Flec op sw.|S-10, 3 No. 1/0 | MB-2 2@, 150/5 emp - MB-2 | F MCC-G=h 600 Manual S-10 6 No.500 - 2g, 480/120-v - - mcm Note: See Appendix for explanation of sebbre 466 ptrument Iocation Interlocking Action Remarks er| Ameter | Wattmeter i - DPI/DPM Close only after S. Reverse current trip. VAR on DPI Supply in series with S. oM | DP3 DP3/DPM - Reverse current trip. VAR on DP3 | Supply from DG-3. Local - Can not close if E Under voltage trip. | \ is closed. . |Local | MB-6 Under voltege trip. - |MB-6 | - - - Voltage for bus and Diesel annunciator. M - DPI/DPM Close only after T Reverse cwrrent trip. Supply 1 series with T. " M | DP4 DPL/DPM Reverse current trip. Supply from D-G-l. Local MB-8 Under voltege trip. MB-8 | . Local - Can not close if Under voltage trip. H is closed. ' - - - Voltege is bus voltage and . Diesel -generator ananunclator. ations. £¥ 467 distribution panel G5-BB (breaker BB), the motor-control center G5-1 (breaker AA), the motor-control center G5-2 (breaker CC), and a spare circuit (breaker DD). See ORNL drawing D-KK~-C-L41176. 19.4,2 Motor-Control Centers’ Motor-control center equipment was manufactured by the General Electric Company. The busses are 600-amp, 480 v, and have a short circuit current capacity of 25,000 amp asymmetrical at 480 v. The circuit breakers are of 100-amp minimum frame size, Datg for the motor-control center equip- ment are given in Table 19.3. 19.4.2.1 TVA Motor Control Centers. Motor-control center T-1 is lo- cated in panels 1 and 2 at the east end of the switch house, as indicated in Fig. 19.4. The bus is supplied with power from the TVA system through the switchgear breaker X. The bus supplies power to three heater dis- tribution centers, Tl-A, T1-B, and T1-C. Circuits T1-D, Tl-£, and T1-F are spares. Motor-control center T-2 is also at the east end of the switch house in panels 8 and 9. Power is supplied through the TVA breaker Y. The bus provides power to two motor-control centers and three heater distribution centers, through circuits T2-S and T2-Z. Three of these are spare circuits. 19.4.2.2 Generator No. 3 Motor-Control Center. Motor-control center G-3% is located on panels 3 through 7 in the east end of the switch house. This bus receives power from switchgear bus No. 3, as mentioned in 19.4.1.2, above. The bus supplies power to 24 circuits in the process system, as listed in Table 19.4. It may be noted that five circuits are omitted from the table since they are spares, 19.4.2.% Generator No. L4 Motor-Control Center. This motor-control center is located in panels 2 through 10 on the north side of the switch house, as shown in Fig. 19.4. Provided with power through breaker F, from switchgear bus No. 4 (see Section 19.L4.1.3, above), this center supplies power to 19 items of process eqpipment. The breaker dats and related in- formation is given in Table 19.5. Fifteen spare circuits are included, to provide a total of 34 circuits. *See footnote, page 19.5 468 Teble 19.3. Equipment Connections to TVA Motor Control Centers Tap and Termination Bresker Starter Intervening Cable No. - Bresgker Size Size Location Equipment and Size (exps) Motor Control Center T-l TL-A Htr Distr T1-A 200 - - - 3 No.4/0 TL-B Htr Distr T1-B 200 - - - 3 No.4t/o T.-C Htr Distr T1-B 200 - - - 3 No.k/fo T1-D-F Spare - - - - 3 No.4/0 Motor Control Center T-2 T2-S HCV 975-A 30 IR MB-3 - 3 No.l2 T2-V Pol E Htr T2-V1 100 - - 75-kva, 480/120, 3 No.2 . 21|'0-V Xfmr . T2-W Pnl E Htr T2-W1 100 - - T5-kva, 480/120, 3 No.2 2"’0 -'V' xmfro T2-X RDM 30 1 Console - 3 No.l2 - T2-Y Htr T2-Y 200 - - - 3 No.lk T-TU Spare T2-TZ Spare Note: See Appendix for explanation of ebbreviations. 3 Tep and Bregker G hFBvo 14 15 16 17 18 19 23 2k 469 Table 19.4. Equipment Connections to Motor Control Center G-3 Termination Instr Pnl 3 C-1 Sump Pumps DCC CcCP MG-2 RCC-1 FOP-1 TF-1 HCV-930A HCV-930B AC-1 Diesel Aux Pnl CCC-1 Instr Pnl WP CTP MB-2 SF-1 Nbféfi Seé Appéndix for explanation of sbbreviations. Bresgker Size (exps) T0 100 30 15 30 15 15 15 15 15 15 100 100 15 50 50 50 30 100 Starter Size On Equip. whbherrererer | Vi Do Location 48-v Pnl MB-2 MB-2 MB-3 MB-3 MB-2 MB-2 MB-2 MB-2 MB-L MB-3 Intervening Equipment 30-kve 4:0/120, 208-v Xfmr Xfer Sw in SH Xfmr Sw from MCC-Gli-5 Xfer Sw MCC-L 7.5-kba 480/120, 240~v Xfmr Cable No. end Size 3 No.b 3 No.2 3 No.2 3 No.l2 3 No.l2 3 No.l2 3 No.l2 3 No.l2 3 No.l2 3 No.l2 3 No.l2 3 No.6 3 No.2 3 No.l2 3 No.l2 3 No.8 3 No.8 3 No.lO 3 No.k Tap and Breaker G-l-2 5 9 1 12 13 16 17 20 21 23 ok 26 a7 29 31 32 33 3h Table 19.5. 470 Equipment Connections to Motor Coatrol Center G-k Termination C-1 DCC MG=5 COP-1 TF-2 DR-1 Aux DP ccce CTP-2 TWP-2 WP RCC-2 MB-k DR-2 480/120,240-v Xfmr Instr Pnl 1 AC-2 AC-3 SF-2 Bresker Size (amps) 100 15 15 15 15 15 30 15 50 50 50 15 30 30 100 100 100 Starter Size Location (2) 1 MB-2 1 48y Pnl 1l MB 1l MB-2 1 On Equip 2 MB-2 2 MB-2 1 On Eguip 1l MB-2 1 MB-4 3 MB-2 3 MB-2 3 MB-3 Intervening Equipment Xfer Sw in SH Xfer Sw 5-kva, 480/120 240-v Xfmr, 1 @ Xfer Sw 5 15 15 15 70 100/60 koo 40O %00 and Size 3 No.8 3 No.8 3 No.l2 3 No.l2 3 No.l2 3 No.h 3 No.lt 3 No.8 Load hp 13 6 : 1-1/2 15 Remarks Both cranes on same fuse and bresker. Two 30-amp fused sw. Vent fan interlocked with circuit No.5. (1) High Bay A-k (2) EsA Time delsay two p sw. AY 480/120,208-v, 3¢ (Lights) Note: See Appendix for eiplanation of abbreviations. Table 19.8. 474 Connections to Lighting Distribution Panels 1A and 1Al Circuit | Lighting Panel Location Lights Location Bresker | Cable, No | Fused . Panel Fuse and Size Sw (exmps) Lighting Distribution Panel 1A o MCR-1 852-ft Elev MCR 400 3 No.4/o Below MCR 1 No.2/0 MCR-2 " MCR 100 Lk No.2 Yes 1 K TRM TRM and East SAl N-5 100/100 | b No.2 Yes 2 C 852-rt Elev MCR 100 4 No.2 in MCR 5 H 840-ft Elev Lights,| 100 4 No.2 Htr, ist Floor B Guard Portal 100 b No.2 Yes 4 D 840-ft Elev 100 L No.2 6 A 852-f't Flev 852-f% Flev, H, 90/100 4 No.2 Yes D‘} HBJJ. l, 2’ 3, MCR 5 J High Bay Ares 90 4 No.2 Sump Vent 7 G 852-I't Elev High Bay Lights 90 h No.2 C-5 Three Roof Vents 8 AB 840-ft Elev 100/100 | L4 No.2 Yes Lighting Distribution Panel 1Al l1 -6 Spares 7 T Store Room Store Room, Diesel | 100/100 | 4 No.2 Yes Diesel House House, SH 8 5 Service Room Service Room 100 k No.2 Note: See Appendix for explanation of abbreviations. 475 Table 19.9. Connections to Building Service Panel No. 2 T Circuit Equipment Bresker Csble, No. Load Remarks Fuse and Size hp (amps) 1 Two 480-v, 3 @ Recept 50 3 No.6 In service area. 2 2 Spare 3 Spare 4 Spare 5 Spare 6 Spare 7 Two 480-v, 3 ¢ Recept 70 % No.k4 Service H, Bl, H HB Ak 8 Spare 9 Spare 10 Spare 11 Roll-up Doors 30 (F) 3 No.lO 2 Top- bottom limit sw. 12 Spare < 13 Two fans, One Htr 30 (F) 3 No.10 South High Bay Area 1% Spare 1 15 Spare L 16 Spare | | | Note: See Appendix for explanation of abbreviations. 476 19.6 Direct-Current Electrical Systems There are two independent direct current electrical systems, an existing 250-v system and a new 48-v system installed for the MSRE. The 25-kw motor-generator set driven by the direct current system to supply emergency power to certain important process equipment is discussed in this section. The locagtion of the major components in the two DC systems is shown on ORNL drawing D-KK-C-55106. 19.6.1 Battery, M-G Set and Distribution Panel for 250-v DC System The 250-v DC system provides emergency power to various important lighting and switching circuits and drives the 25-kw DC-AC motor-generator set used to supply 120/240-v AC power to the control-rod drives, sampler- enricher, etc. The 25-kw DC-AC M-G set is described in Section 19.6.3. 19.6,1.1 AC-DC, 125-kw, 250~v Motor-Generator Set MG-l1. The 250-v DC power source is a Reliance Electric and Engineering Company motor- generator set, Model 1TH-11924, It is mounted in a size 6-FM sheet steel cabinet, with a pressure-ventilating system employing dust filters. The M-G unit is mounted on a fabricated steel base inside the cabinet. The motor is a 200-hp squirrel cage type, frame B-6085, D/5646k2, operating at 1,765 rpm on a 440-v, 60-cycle, 3-phase power supply. It is rated at SOOC temperature rise under continuous duty. The motor has ball bearings and an F-2 mounting with special double shaft extensions. The direct-connected generator has a capacity of 125 kw and supplies power at 250 v DC. The generator frame is No. 385-TY. The unit is a shunt-wound type, with separate excitation at 230 v, and is rated at 50°C temperature rise. The ball-bearing-mounted shaft has special double ex- tensions. An over-speed, normally-closed, switch is mounted on the front end. 19.6.1.2 Battery. The driving motor is supplied with power through breaker W at the TVA switchgear bus. There is also a battery for emergency pover, which consists of 120 Exide cells, Type FOP, rated to discharge 364 amp-hr as the voltage drops to 210 v in a 2~hr period.l75 A reverse- current trip prevents a flow of current from the battery to the generator vhen the motor-generator set is not operating. e ' . Ca 477 19.6.1.3 Distribution Panel. The 250-v DC distribution panel is supplied through & switch and a %00-amp fuse. The following circuits are supplied by the panel through switches and fuses of the size indicated: DC emergency lights (‘30-amp fuse), switchgear trip circuit (60-amp fuse), TVA power transfer switch (30-amp fuse), and the 25-kw M-G set (400-amp fuse). | 19.6.2 Battery, M-G Set and Control Panel for L8-v DC System The 48-v DC system provides power for the electricel- and eir-operated - controls systems. These systems normally receive DC power through either the 3-kw No. 2 AC-DC motor-generator set (driven by AC power taken from the motor-control center G3-9 which is supplied either with power from the TVA or diesel-generator unit No. 3), or through the 3-kw AC-DC motor- generator set No. 3 (supplied with powér-either from the TVA or from diesel- generator unit No, 4)., ' In an emergency, when no AC power is availsble to run the 3-kw motor-generstors, 48-v DC power can be supplied directly from a 2l-cell battery system described below. (See ORNL drawing D-KK-C-55112.) - 19.6.2.1 AC-DC, 3-kw, Motor-Generstor Sets. FEach of the two identi- cal units is en Electric Products Company diverter-pole , motor-generator Type L—7961A.’171*‘ The L4O-v, 3-phase, 60-cycle, AC motor is rated at 5 hp at 1,750 rpm. It draws a meximum of 6.6 amps and is rated at %% temper- ature rise under continuous duty. The direct-connected DC generator is rated at 3 kw (53.5 amps at 56 v). 19.6.2.2 Battery for 48-v System. The 2lk-cell battery supplying the ' 48-v emergency power utilizes Exide "Tytex" Type FOP-19 -'cells.lTZ' The ‘cells have & 12-hr ‘discharge capacity at 600 amp-hr when discharged to 42 volts. The 2k cells normally provide a potential of about 48 volts. % 7-19,6.2.3 Control Panel for 48-v System. The control panel for the 48-v system ils located outside the battery room at the 840-ft elevation. - .The panel 'providés the controls to start and stop the M-G sets, run them - individually or in parallel, to detect system grounds, and to recharge the ‘battery. (See ORNL drewing ‘D-KK-C-55108 and drawing D-KK-C-55109.) 19.6.3 DC-AC 25-kwv Motor-Generator Set MG-h and Connected Ioad This motor-generator set is driven by the 250-v DC system and is used to generate AC power to drive certain important process equipment in 478 in an emergency. The set is a Reliance Electric Model lTH-ll9h6,175 mounted In a size 5-FM sheet steel cabinefi héwing a pressure ventilating system utilizing dust filters. _ The motor is a special direct current motor, frame No. 92-T. It is a shunt-wound type with 1.6l-amp maximum field current. For operation at 1,800 rpm the field controller resistance at 258-v full-load voltage is 36 ohms; for 210-v full-load voltage the required resistance is 40 ohms. The motor is rated at a ho°c temperature rise for continuous service. The ball-bearing-mounted shaft has an F-2 mounting with back end extension. The generstor is én Electric Machinery, frame S5-20, rated at 25 kw at 0.8 power factor. It is a single-phase, 120/240-v, 3-wire unit, with field rheostat, field discharge resistor, and integrally mounted exciter. The generator supplies AC power to the following equipment: instrument panel No., 3 (see Part III); process power panel No. 3, which powers the sampler-enricher and control-rod drive motors; process power panel No. 2, vhich supplies power to the fuel and coolant salt lubricating oil pumps through two 220-v single-phase/U40-v three-phase converters manufactured by the System Analyzer Corporation, Type 35; and the control power for diesel-generator unit No. 5. (See ORNL drawing D-KK-C-41152.) To decrease the load on the 25-kw generator when running the motor on power from the 250-v battery system, the fuel and coolant salt lubri- cating pumps, FOP-2 and COP-2, cen be stopped end the two spare pumps, FOP-1 and COP-1, can be started, these being driven by diesel-generator units No. 3 and No. 4. The instrument power panel No., 2 and the'process power panel No, 2 receive 120/240-v AC power either from the 25-kw motor-generator set or through the 480-v/120, 240-v single-phase instrument power transformer No. 1. This transformer takes its 480-v primary input via the motor- control center bus No. 4 and the TVA system, or in an emergency, from diesel-generator unit No. 4. The secondary of the trsnsformer will be connected to the instrument and process power panels through an sutomatic transfer switch which, on low voltege from the 25-kw -generator, trensfers the load from the set to the motor-control center bus No. 4. This suto- matic switch will not transfer if there is no voltage on the No. k4 bus. (See ORNL drawing D-KK-C-141152.) | C 1 Rt 479 19.7 Heater Control Circuits Power is normally supplied to the process system heaters from the TVA system. In an emergency part of the heaters can be provided with power from diesel-generator set No. 5. The power is distributed through eleven circuit bresker parels to twelve heater control panels and to' one motor control center connection. Power (i.e., voltage) to the heaters is manually regulated by variable autotransformers. There are 136 heater control circuits in the process heating system, including 15 spare circuits. The heaters on the process equipment and piping are described in the sections pertaining to the particular pieces of equipment on which they are employed. 19.7.1 Circuit Breaker Panels G5-1A, G5-1C, G5-1D, T2-V and T2-W These 120-208-v circuit breaker panels are located along the ‘east wall of the north-south hallwey at the 8LO-ft elevation. Panels G5-1A and G5-1C are supplied with pdwer from 112.5-kva transformers, described below. Panels G5-1D, T2-V and T2-W receive power from T5-kva transformers. The circuit breakers supply power to fifty- six 2.8-kva Powerstats and thirty-nine 7.5-kva Type 1256 Powerstats, all located on the heater control panels to be discussed subsequently. 19.7.1.1 Transformers G5-1A and G5-1C, 112.5-kva.. These two transformers are located on the western side of the main building near the switéh house. They are General Electric Company Model gr25Y3005, 480/208Y-120-v, 3-phase, 60-cycle, indoor, dry type transformers rated at 112.5 kva with delta-connected primaries and wye-connected secondaries. " The temperature rise is 80°C under continuous duty at rated load. 19.7.1.2 Transformers G5-1D, T2-V and T2-W, 75-kva. The G5-1D transformer is located on the western side of the main building at " the 840-ft level, adjacent to the G5-1A 112.5-kva transformer. The T2-V unit is located at the 840-ft elevation on the east side of the north-south hallway and the T2-W transformer is on the west side. All units'ére Generai Electric Models 9T23Y5004, T5-kva, 3-phase, 60-cycle, 480-v/120,208-v, transformers, rated at an 80°C temperature rise. 480 19.7.1.3 Circuit Breakers. The breakers used on all five of the &ii above panels are Trumbull Electric Company, Type TQL or R, 100-amp, 120/208-v, three-phase, rated at 4 watts. 19.7.2 Circuit Breaker Panels G5-BB, Tl-A, T1-B, T1-C, T2Y and G5-2Y. These L480-v circuit breaker panels are located on the south side of the east-west hallway at the 840-ft level. Panels G5-BB and G5-8Y receive power from the No. 5 diesel-generator bus; Tl-A, T1-B and T1-C are powered from the TVA motor control center, T-1; and panel T2-Y is supplied from the TVA motor control center T-2. The circuit breakers supply power to thirty-eight 30-kva induction regulators, which are controlled from the heater control panels described below, The breakers used in all six circuits are General Electric Type CCB, 225-amp, 600-v, 3-watt switches, with General Electric Controllers Type CR 2811D-101B, having a 25-hp capacity with 3-phase, 4L0-600-v power. 19.7.3 Circuit Breaker Panel G5-2X and Drain Line 10% Heater Circuit. Circuit breaker panel G5-2X takes power from the switchgear bus No. 5 to supply a saturable reactor and a high-current transformer to provide stepless control of the current to the resistance-heated drain line 103. 19.7.3.1 Saturable Reactor. The saturable reactor is a Hevi- L Duty Electric Company, Catalog No. D-7333l, single-phase, 60-cycle, unit, rated at 25 kva, 460 line volts, a load voltage of Llh at 60.5 . amps, and with a DC control input of 4 to 75 v. The total resistance is about 54 ohms. The reactor is located in the north electric service area between columns 5-B and 5-C at the 824-ft elevation. The 4 to 75-v DC control current to the saturable reactor is provided by germanium diode rectifiers mounted in the cabinet of heater control panel No. 8. The DC output of the rectifiers is varied by controlling the AC input through a Type 136 Powerstat mounted on the control panel. (The Powerstat is described in Section 19.7.4, below). A current transformer and ammeter on the control panel provide indi: cation of the heat input to the drain line. X 481 19.7.5.2 Special 25-kva High-Current Transformer. The output of the saturable reactor is fed to a special 25-kva transformer located in the drain tank cell. The transformer was manufactured in accordance with ORNL Dwg B-MM-A-562L44k by the Hevi-Duty Electric Company. The pri- mary is rated at 420 v and the secondary at 18 v. The unit supplies the heavy current of up to about l,MOO amps needed for resistance heating of the INOR-8 1-1/2-in. sched 40 drain line 103. The ungrounded side of the transformer is electrically connected to the drain line about midway between the reactor and the drain tank and the ends of the drain line have ground wires to the grounded side of the transformer. 19.7.4 Heater Control Panels and Equipment The twelve heater control panels are located in the north-south hallway at the 84O-ft level, with panels 1 through TA on the west side of the hallway facing panels 8 through 11. Two additional heater panels are in the same general location to control the heaters in the fuel processing system. These are described in Part VII. A list of the heaters controlled by each panel and the controls showing on the face of the panel is given in Table 19.10. The heater panels are supplied with power from the circuit breaker panels described in Sections 19.7.1 and 19.7.2, above. Some of these breaker panels supply as many as five different heating panels. There are no heaters in the process system having the power input automatically adjusted by heat-sensing devices and controls systems. The povwer is regulated by manual adjustment of the voltage at the heater con- trol panel in response to témperature indications in the nearby tempera- ture-scanning instrumentation, see Part III. 19.7.4.1 Type 136 "Powerstat." This panel-mounted, hand-positioned variable autotransformer is a product of the Superior Electric Company and is rated at 2.8 kva, 20 amps, 120 v, 60-cycle, with O to 120-v out- put. A schematic wiring diagram is shown in Figure 19.5, There are a total of 67 of this type of control. 482 Unclasgsified ORNL DWG 64-8849 H200-14~F1 H200 =14 -A1 fi H200-14-H1 Powverstat 4 H200 =14 To Hesater H200-14 ™y H200 =14 -F2 H200 =14 -H2 o 1 L %20 A Figure 19.5. Typical Schematic Wiring Diagram for Type 1256 Powerstat. FT201B-1-F1 FT201B~1-Al mF‘I‘EOlB-l-Hl 3 _/ Powerstat FT201B- 1 To Heater) w Fr201B-1-H2 a. Typical Hester Connection ‘ F20k-1-F1 . FV20h-1-F1 mFVEOh-fl.-Cl G5=1~Dl-2 E 3 u I —) O————-Jp Control Rela,y/ / 120 v 2 :D Powerstat FV2oh-1-Hl > Frook-l To Freeze { ‘p Valvg FV204 - S Py e { '? FV204-1-H2 4 b. Typical Connection to Freeze Valve Figure 19.5. Typical Schematic Diagrem for Type 136 Powerstat. C » {], 483 Table 19.10 Heater Control Panels* Heater Location Heater HCP-1 Cooclant System: Radiator CR1 " CR 2 " CR 3 " CR 4 " CR 5 " CR 6 " CRT " CR 8 Loop piping H200-15 " H201-12 " H202-2 Spare No. 16 Spare | No. 1 Spare ~ No. 2 HCP-2 Coolant System: Radiator CR 1 CE L CR 5 CR 6 Loop Piping H200-14 Sleeves o - H200-15 H201-10 o H201-11 Piping Inside H201-13 Radiator . *% Control on Panel¥*¥ On-off and Raise- Lower Push Buttons and 50/5-amp ammeter Ditto, but 40/5 amp Ditto, but 40/5 amp Ditto, but 50/5 amp Ditto, but 50/5 amp Ditto, but 50/5 amp Ditto but 4O amp Ditto but 4O amp Ditto but 40/5 amp Ditto, but L0/5 amp Ditto but 40/5 amp Ditto, but 15 amp Ditto, but 4O amp Ditto, but 4O amp 0-300-v Ground Detection Voltmeter and 3 Line Selector Buttons " " " Powerstat Type 1256 and 15-amp ammeter Ditto, but 30 amp Ditto, but 30 amp Ditto, but 20 amp Ditto, but 20 amp See panel layout ORNL Dwg E-MM-Z-51624. Panels 1 through TA are in west group, panels 8 through 11 are in east group. Controls are listed as appearing on panel, reading left to right, top to bottom. 484 Heater Location Heater Control on Panel HCP-3 Coolant System: Loop Piping H202~1 Powerstat Type 136 : and 15 amp ammeter Loop Piping H20L -2 " Loop Piping H205-1 " Freeze Valve Pot FV204-3 - " Flow Transmitter: Body top FT201A-1 n Body top FT201A-3 " Body bottom FT201A-2 " Body bottom FT201A-4 " Body top T201B-1 " Body top FT201B-3 " Body bottom FT201B-2 " Body bottom FT201B-4 " Fill Line H205-2 " Spare No. 5 " Level Element = LE-CP-1 Pipe Level Element LE-CP-2 " Pot HCP-4 Coolant System: Freeze Valve FV20k-1 Powerstat Type 136 and 20 amp ammeter Adjacent to FV FV20L-2 " Freeze Valve FV206-1 " Adj. Freeze FV206-2 " Valve Fill Line H20k-1 Raise-Lower Buttons and 30 amp ammeter Fill Line H206-1 no Drain Tank CDT 1 " Bottom Fill Line H203-1 " Drain Tank - Lower CDT 2 Powerstat Type 1256 and 30-amp ammeter Drain Tank - Upper CDT 3 " Coolant Pump-Bottom CP 1 Coolant Pump - Side Cp 2 1" ” L3 HCP-5 Reactor Cell: 485 HCP-6 Reactor Cell: Heater Location Heater Coolant Piping ~ H200-1 Ad jacent Flange 200 H200-11 Ad jacent Flange 200 H200-12 Adjacent Flange 201 H201-1 Adjacent Flange 201 H201-2 Coolant Piping H201-9 Ad jacent Flange 100 H100-1 coolant pios H200-2 oolant Piping - H200-: Control RCH-1 HQOO-EA H200-4B Coolant Piping f H200-5 Control RCH-2 'H201-8 Coolant Piping 328823 Control RCH-3 H200-8 H200-9A Coolant Piping gggg:gi | - | H201-4B Reactor . . R1 Reactor R2- Reactor | ~ R3- ‘Adjacent Flange 100 HL00-2 Adjacent Flange 101 HLO01-2 Adjacent Flange 101 H101l-3 Control on Panel Powerstat Type 1256 and 20 amp ammeter Ditto, but 30 amp Ditto, but 30 amp On-0ff and Raise- Lower Buttons and 3 LO-amp ammeters Ditto, but 30 amp Ditto, but 40 amp Ditto, but 4O amp 0-150-v Ground Detection Voltmeter and 3 Line Selector Buttons n " Povwerstat Type 1256 and 20 amp ammeter n HCP-7 Reactor Cell: HCP-TA Reactor Cell: 486 Heater Location Coolant Piping Control RCH-5 Coolant Piping Control RCH-6 Fuel Piping Control RCH-T Fuel Piping Reactor Furnace Reactor Furnace Reactor Furnace Heat Exchanger Heat Exchanger Heat Exchanger Fuel Pump -~ Lower Fuel Pump - Upper Spare Spare Heater H200-10 H201-3 H201-5 H201-6 H201-T H101-1 H102-3 H102-2 R1 R 2 R 3 HX 1 HX 2 HX 5 FP 1 FP 2 Reactor Access Nozzle RAN-1 Reactor Access Nozzle Ran-2 Spare Spare Spare Spare Spare Spare Fuel Piping Ad jacent Flange 102 Adjacent Flange 102 H102-1 H102-4 H102-5 Control on Panel On-OFF and Raise- Lower Buttons and 3 30 amp ammeters Ditto, but 40 amp Ditto, but 30 amp Ditto, but 30 amp Dittd, but 40/5 amp Ditto, but 40/5 amp Ditto, but 40/5 amp Ditto, but 40 amp Ditto, but 40 amp Ditto, but 4O amp Ditto, but 40/5 amp Ditto, but 40/5 amp Ditto, but 40 amp Ditto, but 40 amp d. Powerstat Type 136 and 20 amp ammeter tr 1" " T " " "t Powerstat Type 1256 and 30 amp ammeter Ditto, but 20 amp Ditto, but 30 amp 487 Heater Location Heater Control on Panel HCP-8 Drain Tank Cell: Reactor Fill Line H 103 Powerstat Type 13%6¥%, 2 on-off push-button stations and 50/5 amp ammeter Freeze Valve FV 103 Powerstat Type 136 and 20 amp ammeter Adjacent Furnace H104-1 " Spare FFT o, T " Spare No. 8 " Drain Tank-Lower FFT-1 On-0Off and Raise- Lower Push Buttons and three 40/5 amp ammeters Drain Tank-Upper FFT-2 " Drain Tank-Lower FD1-1 " Drain Tank-Upper FD1-2 " Drain Tank-Lower FD2-1 " Drain Tank-Upper FD2-2 " HCP-9 Drain Tank Cell: Freeze Valve FV10k-1 Powerstat Type 136 and 20 amp ammeter Freeze Valve Pot FV10L4-3 " FFT Fill Line H10k4-5 " FFT Fill Line H104-6 " Freeze Valve FV105-1 " Freeze Valve Pot = FV105-3 0 Adjacent Furnace FD2 H105-1 " FD-2 Fill Line H105-b o Freeze Valve ~ FV106-1 | "o Freeze Valve Pot FV106-3 Com Adjacent Furnace FD1 H106-1 " FD-1 Fill Line H106-4 " Spare No. 9 oon Spare No. 10 " ¥ This Powerstat controls the DC current for the saturable reactor wired in the primary of the transformer for the resistance-heated line. 488 Heater Location HECP-10 Drain Tank Cell: Heater Adjacent Freeze Valve FV1Oh-2% FFT Fill Line H10Lk-2 FFT Fill Line + H1Ok-3 FFT Fill Line H10L-k Adjacent Freeze Valve FV105-2% FD-2 Fill Line H105-2 FD-2 Fill Line H105-3 FD-2 Fill Line H10L4-T7 Adjacent Freeze Valve FVL06-2% FD-1 Fill Line H106-2 FD-1 Fill Line H106-3 Transfer Line H110-2 Transfer Line H110-3 Spare No. 12 Spare No. 13 Spare No. 14 Ad jacent Furnace FFT H1OT-1 Transfer Line H107-2 Ad jacent Flange H1O07-3 Freeze Valve FV107-1 Ad jacent Freeze Valve FV10T7-2¥ Freeze Valve Pots FV107-% Control on Panel Raise-Lower Button and 20 Ditto, Ditto, Ditto, Ditto, Ditto, Ditto, Ditto, Ditto, Ditto, Ditto, Ditto, Ditto, Ditto, Ditto, Ditto, amp but but but but but but but but but but but but but but but 20 50 50 20 20 50 50 20 30 30 %0 50 30 30 30 ammeter amp amp amp amp amp amp amp amp amp amp amp amp amp amp amp Powerstat Type 136 amp ammeter and 10 Ditto, Ditto, Ditto, Ditto, Ditto, but 10 but 20 but 20 but 20 but 20 amp amp amp amp amp ¥ These circuits were left in place although due to design changes the heaters have been eliminated. 489 Heater Location Heater Control on Panel HCP-11 Drain Tank Cell: Ad jacent Furnace FD-2 H108-1 Powerstat Type 136 and 10 amp ammeter Transfer Line FD-2 H108-2 Ditto, but 10 amp Adjacent Flange H108-3 Ditto, but 20 amp Freeze Valve FV108-1 Ditto, but 20 amp Ad jacent Freeze Valve FV108-2% Ditto, but 20 amp Freeze Valve Pots FV108-3 Ditto, but 20 amp Ad jacent Furnace FD-1 H109-1 Ditto, but 10 amp Transfer Line FD-1 H109-2 Ditto, but 10 amp Adjacént Flange H109-3 Ditto, but 20 amp Freeze Valve FV109-1 Ditto, but 20 amp Ad jacent Freeze Valve FV109-2¥ Ditto, but 20 amp Freeze Valve Pots FV109-3 Ditto, but 20 amp Transfer Line H110-1 Ditto, but 10 amp Spare No. 15 Ditto, but 20 amp ¥ These circuits were left in place although due to design changes the heaters have been eliminated. 490 19.7.4.2 Type 1256 "Powerstat". This Superior Electric Company variable autotransformer is panel-mounted and hand-positioned and similar to the Type 136 but is rated at 7.8 kva, 28 amps, with 240 v input and 0 to 280-v output. A typical schematic wiring diagram is shown in Figure 19.6. Twenty-two of these "Powerstats" are used. 19.7.4.3 Motor-Operated Type 1256-10%5 "Powerstat". This variable afitotransformer is motor-operated and mounted on a rack on the west side of the north-south hallway between columns C-2 and C-3 at the 840-ft elevation. It is controlled by a "raise-lower" push button on the heater control panel. The unit is manufactured by the Superior Electric Company and is rated at 7.8 kva, 28 amps, 240 v input and 0 to 280-v output, single-phase. The motor is operated on 115 v, 0.4 amps, and has a 45 sec travel time. A typical wiring diagram is shown in Figure 19.6. Twenty of the controls are of this type. 19.7.4.4 Induction Regulator. Thirty-eight induction-type voltage regulators were existing in Bldg 7503 as part of the ART. They are located on the west side of the north-south hallway at the 840-ft level, and below this elevation on the south side of the east-west hallway. Each regulator is a General Electric Company Type AIRT Cat No. 3263366, and are rated at 480 v, three-phase, 36.5 amp, and 30-kva. ZEach is positioned by "raise-lower" buttons on the heater control panels. Since \ the regulators can not produce zero voltage, "on-off" buttons are provided on the heater control panels. A listing of this "on-off" button for a heater tabulated in Table 19.10 identifies use of an induction regu- lator, with the one exception of the drain line heater., The regulators have mechanical stops to limit the voltage output to 208 v. A | schematic wiring diagram for the induction regulator and a motor operator are shown in Figure 19.7. There are 38 of the induction regulators in use. Nine feed 30-kva three-phase transformers which supply heater breaker panels. Eleven of the regulators supply 1lO-kva single-phase transformers, one transformer for each phase. The transformers are described below. The remaining regulators feed power directly to the heater breaker panels. The e number of heaters supplied by a regulator depends upon the size and \.J application of the particular heaters. Unclassified ORNL DWG 64-8850 120 =v D3-3N See Figure 19.5 for Wiring — Disgram of Type 1256 Powerstat G5-1-D3-3 H20L-1-T2 HoO4 -1 -T3 e, —-—c-i-b———j e = ] Push Buttons on Control Powerstat Drive Motor Panel HCP Figure 19.6. Typical Schematic Wiring Disgrsm for Motor-Opersated Type 12561035 Powerstet. 16% Unclassified ORNL DWG 64-8851 & G5-1-D3-1 D3-1H L °\ _°y 65-BB-3 "_‘OAC ? )- o-) oa 5 A ofe r—f—--—- ~F=1- ol o ‘ = Contactor [ On ; . | R | crm-c2 L. CRC3 R | i © I CRL-C1 ! ! l ) LT — o._lL.p -7 Pushbuttons on Control Panel HCP See Figure 19.6 for schematic wiring disgram of motor operator. Induction Regulator CRL ~ Figure 19.7. Motor-Operated Induction Regulator coY 493 19.7.4.5 Three-Phase 30-kva Transformer. There are nine of these transformers located on a platform behind the heater breaker panels in the east-west'hallway at the 840-ft level. Each is a Jefferson Electric Company, Cat No. 223-19&, "pPowerformer", rated at 30-kva, three-phase, 60-cycle 480 A/208-120 v, 36.1 amp and for 150°C temperature rise. The transformer secondaries are provided with ground- detection voltmeters mounted on the heater control panel. See ORNL Dwg D-KK-C-55137. 19.7.4.6 Single-Phase 10-kva Transformers. Thirty-three of these transformers are mounted on the wall of the south side of the platform mentioned sbove. Each is a Jefferson Electric Company, single-phase, dry-type transformer, Cat No. 243-466, rated at 10-kva, 240-480-v primary and 120-240-v secondary at a 150°C temperature rise. The primaries are delta-connected and the secondaries are wye-connected and grounded. ©See ORNL Dwg D-KK-C-55137. 19.7.4.7 Heater Breaker Panels. As stated above, an induction regulator may supply several different heater circuits. In such cases, each heater circuit is prov1ded with a circuit breaker. Since most of the breakers and panels are existing equipment adapted for the MSRE, there is a variety of comblnations of makes and styles. Seven panels of circult breskers are mounted on the east wall of the north-sofith hallway. Two panels use fourteen Trumbull Electric Company, Type TQL, or R, 120/208-v, three -phase breakers, having various current ratings. Four panels use General Electric Company Type TF 136020, 600-v, 5-pole breakers with several different current ratings. There are three spare circult breakers included. ~ Six panels of heater circuit breakers are located along the south 51de of the east-west hallway. Each panel contains four General Electric Company Type CCB, three—phase, circuit breaker mounting panels, seventeen of which are rated at 600 v and seven at 120/208 v. The mounting panels may contain up to 20 circuit breakers but only 5 to 8 are usually in use. Four of the mounulng panels have Westinghouse De-Ion, F Frame, Style 1222033 circuit breakers. Thirteen panels use General Electric Company Cat No. TF 136020 for 600 v; five use General Electric Type ES-93 and two General Electric Type EP-37,both rated at 125 v, 494 19.7.5 Heater Leads Electrical leads for the process heaters in the coolant cell are multi-conductor No. 19/22 Type TW cable run in trays and conduit from the heater control equipment to & junction box in the special equip- ment room. From this box, multi-conductor No. 19/22 RH cable is run in trays to the equipment in the cell. Electrical leads for heaters in the reactor cell are multi-con- ductor No. 19/22 Type TW cable, laid in trays between the heater con- trol equipment and junction boxes in the south electric service area. The leads for the drain tank cell are identical except that the junc- tion boxes are located in the north electric service area. The con- nections between the junction boxes and the cell equipment are made with mineral-insulated, copper-sheather cables carryifig three No. 10 or 12 wires. These pass through the cell walls in 3/4-in. pipe size penetrations described in Section 19.8, following. The heater leads passing through each penetration are listed in Table 19.11. Inside the cells the cables are run in square duct, either to junction boxes or to special 600-v, 50-amp, metal-and-ceramic, fe-- male disconnects. The disconnects, as illustrated in Figure 19.8, are mounted in the cells convenient to the heater served and are located in a manner to facilitate remote manipulation. The cell ends of the cables are sealed with brazed bell-end housings. The \; outside ends are sealed with a General Cable Co. insulating cap and | threaded gland using a cold plastic sealing compound. There are eight spare leads to the reactor cell and fourteen for the drain tank cell. Some of the process heaters which are designed for removal and replacement have male, 600-v, 50-smp, 3-wire disconnect plugs mounted directly on the removable unit. The connection between the matching female disconnect and the porcelain terminal blocks in the junction boxes inside the cell is made with ceramic-beaded nickel alloy 99 wire, sheathed in 1/2-in. OD flexible steel hose. Permanent heaters have the same type of flexible leads connected directly to the heaters. The leads pass through junctions, where (fiy the heaters are connected in parallel, and continue to terminate in z 495 y ' Unelassified ORNL DWG 64-8852 1/2-in. Cersmic Insulator With Disconnect Plug Ralco Mfg. Co. ‘) No. 10 AEC "Fish Spine" 3 No. 10 stranded Ceramic Besads Copper Conductors Electrode Crimped in Conductor 1 "Leva A" Spacers - Every 6-12 in. Disconnect Receptecle Ralco Mfg. Co.,No. 10 AECR, 80-zmp, 600-v AC 3 Pole. o] ' >) Lead Brazed to . } I ‘ Terminal i v ™ "Fish Spine"” Ceramic Beads "MI" Cable End Seal ' Ceramasesl Co. No. 805B0110-3 Two 3/4-1in. Locknuts Threaded Gland Generel Ceble Corp. No. 434 P y 3/c No. 12 "MI" Ceble ———-—I ll Figure 19.8. Male and Femele Electrical Disconnects for Heater | - Leeds Inside Cells. iy 496 Table 19.11 Heater Electrical Lead Cell Wall Penetrations DISCONNECT No. H520-4S H520-33 H520-25 H52C-18 H520-4 H520-3 H520-2 H520-1 H520-5 H200-2 FP-k H200-7 H200-SP H520-T7S H520-65 H200-1 H100-2 H100-1 H520-7 FP-5 H200-8 RCC-2 H520-6 H520-58 H200-4 H200-3 H200-6 FP-SP H200-9 HX3 HX2 PENETRATION R-2 - REACTOR CELL SLEEVE No. TRAY east east center east center center ¥ Estimated length LENGTH* Lk O o~ OV W D W W AW DR NY D NN EE E R FE R E R R W R HFOWYW A WV FuWnE OWw ®-~1 W &£ WM H O CABLE SIZE 3/c No. 12 3/e No. 12 !l}r F3 497 Table 19.11 Cont'd. DISCONNECT No. TRAY LENGTH SLEEVE No. CABLE SIZE HXL center 38 3k 3/c No. 12 H200-10 center 30 35 PE-1 east 29 36 FP-1 27 37 H200-5 | 29 38 FP-2 2k 39 PE-3 31 4o H200-10 center 31 b1 H200-11 center 31 Lo PE-2 east 29 43 FP-3 22 I v PENETRATION R~3 - REACTOR CELL DISCONNECT No. TRAY LENGTH SLEEVE No. CABLE SIZE 1 Hi Level Gamma 2 Hi Level Gamma 5 I > 6 RH-SP1 east 45 7 3/c No. 10 R2-2 L7 8 R2-3 b7 9 R3-1 L8 10 R2-1 40 11 ' H201-SP1 west 45 12 3/c No. 12 H201-3 west 31 13 H102-1 center 37 14 Y RL-1 center 43 15 3/c No. 10 LIFP-1 center 32 16 3/c No. 12 17 R3-2 west 57 18 3/c No. 10 Table 19.11 Cont'd. 498 DISCONNECT No. TRAY LENGTH RH-SP2 west 57 R3-3 56 H201-7 46 H201-k4 38 H102-1S center 37 R1-2 39 LIFP-2 53 H101-3 4o H201-9 west L8 H201-8 [ L7 H201-5 43 RH-SP3 center Ly Ri-5 36 LIFP-3 3y H102-3 39 H102-4 40 H102-2 .y 27 H201-2 wvest 32 RCC-1 49 FV103 5k H201-5P2 ! 4o H102-5 center 4o H101-2 57 H101-1 %9 H201-1 west 28 H201-6 ‘ 42 SLEEVE No. 19 20 21 22 23 ol 25 26 27 28 29 30 31 32 33 3h 35 36 37 38 39 4o 41 4o 43 i CABLE SIZE 3/e No. 10 3/0 No. 12 3/ec No. 10 3/c No. 12 3/c No. 10 3/c No. 12 {4 Y Table 19.11 HEATER No. H103 FFT-2 FFT-SPL FFT-3 FFT-4 H107-1 H107-2 H107-3 H107-SP FFT-6 FFT-5 H108-1 FD2-2 H108-2 FD2-SP1 FD2-% FV107-2 FV107-1 FV107-3 H108-3 H108-SP FD2-4 FV108-2 FV108-3 FV108-1 FD2-SP2 H110-1 FD2-5 FDi-3 H109-SP H109-2 FV109-1 FV109-3 Cont'd. WEST SIDE - DRAIN TANK CELL 499 LENGTH 67 71 Th T3 67 63 66 66 64 69 67 66 67 62 65 66 69 67 66 61 60 63 63 60 60 65 59 63 64 58 58 57 57 END CONNECTION disconnect Junct. box disconnect Jjunct. box disconnect Junct. box disconnect Y Junct. box disconnect Jjunct. box disconnect CABLE SIZE 3/c No. 10 3/c No. 12 ta 500 Table 19.11 Cont'd. HEATER No. LENGTH END CONNECTION CABLE SIZE FV109-2 54 disconnect 3/c No. 12 FD1-4 57 junet. box FD1-SP1 58 disconnect H110-2 60 H109-3 61 H110-3 61 H109-1 50 FD1-5 50 Junct. box FD1-SP2 51 disconnect FD1-6 50 junct. box FD1-7 52 H106-1 45 H106-2 46 l H106-3 b1 EAST SIDE - DRAIN TANK CELL HEATER No. LENGTH END CONNECTION CABLE SIZE DCC 79 disconnect 3/¢c No., 12 FFT-1 53 Junct. box FFT-5SP2 53 disconnect FFT-8 48 junet. box H104-1 Ly H104-2 45 H10k4-3 L6 FFT-T7 L7 FD2-1 50 FD2-SP3 L6 disconnect H105-SP 46 " H105-4 45 junet. box H105-1 L FD2-8 L6 H105-2 43 H105-3 4y FV104-3 45 .y N [\ FA Table 19.11 HEATER No. FV104-2A FV104-1 FD2-7 H105-4 FV104-2D FV105-2D FV105-1 H10L4-5 H104-SP FV105-24 FV105-3 FV10L-6 H104-7 ¥D2-6 H104-T7S FD1-~2 H106-4 FV106-1 ¥FD1-SP3 FD1-1 FV106-2D FV106-3 FV106-2A H106-SP Cont'd. LENGTH by b7 40 Ll Ly b3 Lo Wl b7 W b1 46 b3 k7 39 46 37 36 s 43 36 39 36 37 501 END CONNECTION Jjunct. box disconnect Jjunct. box disconnect Junct. box disconnect Junct. box ' disconnect Junet. box disconnect CABLE SIZE 3/c No. 12 ' 502 male plugs, as illustrated in Figure 19.9. These are plugged into the female disconnect fittings which are the terminus of the mineral-in- sulated cables brought into the cell. Table 19.1l1 also list the mineral-insulated cable data for each heater lead, including the length, wire size and type of terminal used. When single-phase heater circuits are required, one wire of the three-wire cables is not connected. 19.8 Cell Wall Penetrations for Electrical Leads Copper or stainless steel sheathed, mineral-insulated cables are used for the electrical leads passing through the walls of the reactor containment and drain tank cells. The cable passes through individual pipe sleeves with compression fittings at each end to form a leak-tight joint around the sheaths. Although gas diffusion through the mineral insulation is considered negligible, the sheaths are also sealed at each end. The number of cable sleeves at each penetration is indicated in Tables 19.12 and 19.13. The heater leads in pene- trations II (33) and III (32) are listed in detail in Table 19.11. 19.8.1 Sheathed Cable. The mineral-insulated sheather cable is manufactured by the General Cable Company. The catalog numbers for the various numbers of conductors and wire sizes are listed in Table 19.14. Copper sheathing is used on all MI cable leads. The reactor cell end of a sheath is sealed with a brazed-on Ceramaseal MI cable pothead, Cat. No. 805B-0110, or Olll, etc. The end of the sheath outside the cell is sealed with a screwed-on pothead filled with a cold-setting plastic insulating compound. See ORNL Dwg. E-MM-Z-56238. 19.8.2 Cable Sleeves. The MI cable passes through the cell walls in individual sleeves of 3/8-in. IPS to 1-in. IPS, depending on the cable size. These pipes have a minilmum of a 2-1/2-in. offset at the midpoint through the cell wall to prevent radiation from streaming through the opening. | *, o ‘_t 503 Table 19.12 Summary of Eiéctrical Lead Penetrations in Reactor Cell MSRE Pene- Former Pene- Function Number of Sleeve Size tration No. tration No. Sleeves IPS - Schd. 40 ' 6 1 in. IT R5 Electrical 58 5/h in. : 6 1 in. III R2 Electrical 38 5/4 in. IV Thermocouples T 5/4 in. ® — 28 1/2 in. 25 3/8 in. v R Instrumentation 60 3/8 in. XXIII , R7 Thermocouples 38 3/8 in. Table 19.13 Summary of Electrical Lead Penetrations in Drain Tank Cell MSRE Sleeve Numbers Function A-1 to A-36 Instrumentation B-1 to B-36 Instrumentation C-1 to C-36 | . Thermocouples D-1 to D-36 o Thermocouples E-1 to E-36 Thermocouples A-3T to A-60 Electrical ‘B~37 to B-60 - Electrical C-37 to C-60 Electrical D-37 to D-60 Electrical E-37 to E-60 Electrical _F-37 to F-60 o Electrical Teble 19.14% General Cable Company MI Cable Numbers - Number Wire Sleeve Size Gen. Cable Conductors Size ~in. IPS Cat. No. 16 1/2 387 3 12 5/h 43l 7 16 5/k kg 3 10 | 3/h 480 3 6 1 621 504, The cable sleeves are grouped to pass through a poured concrete plug mounted in existing penetrations in the reactor containment vessel wall, or, in the case of the drain tank cell, are arranged on a rectangular grid in the poured concrete of the 3-ft-thick east wall of the cell. See ORNL Dwg D-KK-C-4O94T for the drain tank cell sleeve layout. All drain tank cell cable sleeves are 3/k-in. IPS. The cable sleeves have pipe couplings screwed to each end to accept a General Cable Company compression gland. This fitting con- sists of a compression sleeve and nut to effect a leak-tight seal around the MI cable sheath. See ORNL D gs D-HH-B-40539 and Figure 19.9.. 19.8.3 Reactor Cell Penetration Plug and Sleeve. Existing reactor containment vessel penetrations consist of sleeves, about 23-in. ID, with one end welded to the inner contain- ment vessel wall and the other end to the wall of the ocuter vessel. A corrugated bellows midway between the ends permits relative movement between the two vessels, as shown in Figure 19.10 and on ORNL Dwg D-KK-D-40976. A plug, about 22-5/4-in. OD x 3 £t 5 in. long, fits into the above-mentioned sleeve, and is welded to it on the outside end. This plug consists of a carbon steel sleeve, about 22 in. ID of 3/8-in. wall thickness, with end plates welded to it through which the cable sleeves pass. These sleeves are welded to the plates at both ends, using a trepanned groove at each weld. The space between the cable sleeves inside the plug is filled with concrete. See ORNL Dwg E-BB-D-41864, of Unclasaified CRNL-TWO 64-5661 THREADED PIPE _ CoUPLINT. . : . . PENETRATION SLEEVE PENETRATIOM PLUG SLEEVE H 2% MIN.OFFSET | | { NPa (TYPICAL) ' I M1 ZABLE SLEEVE ,'d '. CONMCRETE . _» CTECONDOLTOR BETWEEHN CABLE SLEEVES " a “a COPPER-SHWATHED == [ — | FIGURE 19.9 TYPICAL ELECTRIC LEAD PENETRATION OF REACTOR CELL WALL H G0¢ 506 20. BUILDING SERVICES 20.1 Potable Water The source of potable water for Building 7503 is briefly described in the discussion of the site, Section 3 and shown in Figure 3.3. The water is normally obtained from the two 1.5 x 10 -gal reservoirs east of the site, with flow from east-to-west in the 1l2-in. water main along 7500 Road. These reservoirs have a maximum water level elevation of 1,055 ft, providing a maximum pressure of about 93 psig at the 8ho-ft elevation in Building 7503. Potable water can also be provided by west-to-east flow in the 6-in. main along 7500 Road, as indicated schematically in Figure 20.1. Both sources connect to the same 6-in. tee supplying the building. The 6-in. potable water main enters the north end of Building 7503 at about the 840-ft elevation, where it then divides into two major branches. One 4-in. main supplies all building services, such as water closets, lavatories, sinks, showers, drinking fountains, etc. The other 4-in. main provides water for the fire protection system, as discussed in Section 20.10. 20.2 Process Water Process water is supplied to the MSRE from the same potable water mains at 7500 Road, but through a different 6-in. main leading from the road to the east side of Bldg. 7503, as shown in Figure 20.1l. There are two shutoff valves outside the building at the 848-ft elev. A back-flow preventer is installed in the line just inside the building to relieve water to the building drain in event the building process water pressure should exceed the supply pressure. Piping connections and valves are provided for installing a spare back-flow preventer should this be found necessary. Distribution of the process water to the MSRE systems is discussed in Section 15 and shown on the flowsheet, Figure 15.1 (ORNL Dwg D-AA-A-40889). | ¢ X . 6 in. 6 in. Fro:m X~10 / N / Fire —~Potable Water %818 Plug /6 ino To Outside 819F Shl Siamese Conn -6 in. Elev 845 £t e o r Y in. | | | | | l | | To | ) | To Hose To Building | r 6 in | Cabinets Sprinklers Services | l ' X | l | To Elev 848 ft | { 6 in. Process | Services | Backfilow I | Preventer — — — _ _ _Bullding 7503 — 1 Flgure 20.1. Water Services to Bullding 7503. Unclassified ORNL DWG 64-9108 12 in. From Two 8 i l, 500,000"%8:]- ~ . Water Tanks 09 508 20.3 Building Lighting The 13.8-kv feeder lines supplying electric power to the MSRE site are briefly described in Section 3 and shown in Figure 3.4. A bank of three 250-kva, 13.8-kv to 480-v, transformers located on the east side of Bldg 7503 supplies power for interior and exterior lighting, air conditioners, and general office and building uses. There are two main distribution panels. Panel No. 1, located at the 840-ft level, has a capacity of 750 amps and supplies the 3~ton and 10-ton cranes, the control room air conditioning equipment, the main floor unit heater and fan, and the basement area unit heat and fan. This panel also provides power for a h80-v/120-v-2h0—v transformer supplying Panel 1A. This 750-amp panel distributes power to the control room panels, lighting, the high-bay area roof vent fans, the sump pit vent fan, and to Panel 1Al, which supplies the remainder of the light- ing circuits. Panel No. 2, of 325-amp capacity, supplies the remaining unit heaters and vent fans and the 480-v building outlet receptacles. The electric building services are shown on ORNL Dwg D-KK-C-L113k. 20.4 Fencing The MSRE site 1s a non-classified area and security guards are not required. An 8-ft Cyclone fence serves as a perimeter enclosure. Vehicular gates are provided at the northwest and southeast corners and a 30-ft-wide main gate is located at the north end of the building. 20.5 Steam Supply Saturated steam at 240 psig is supplied to Building 7503 from the X-10 power plant through a 6-in. main as shown in Figure 3.5. The pressure is reduced to 50 psig at a reducing valve station on the east side of the building. The main then enters the building at about the 842-ft elevation, where it then divides into numerous branches supply- ing steam throughout the building. Condensate is not returned but is discharged to the building drains. ™y vl 509 20.6 Roof, Foundation and Floor Drains Storm water from the roof drains flows through a 6-in. line to a catch basin located west of Bldg 7503 with an invert elevation of 837 ft, as indicated in Figure 20.2. A 12-in. reinforced concrete pipe carries the water from the basin to a drainage area west of the building, leading to Melton Hill Branch. The various floor drains, etc., emptying into the sump room are listed in Table 1k.1. As described in Section 14, sump pumps deliver the water to another catch basin, with an invert elevation of 843 ft, to drain through a 12-in. reinforced concrete pipe to the same drainage area mentioned above. 20.7 Sanitary Disposal The Building 7503 sanitary waste system piping is directed to a septic tank located about 100 ft west of the building at an elevation of 840 ft. The drainage field is outside the perimeter fencing and about 250 ft west of the building. 20.8 Air Conditioners The main control room and the data processing room are air con- ditioned by a Trane Company steam-heated coil, blower and filter unit located at the 852-ft elevation in the hallway south of the control room, and by an evaporator coil in the discharge ducting from the heater unit. This direct-expansion coil is supplied with Freon-12 from a 15-ton Worthington 2VC-6 reciprocating compressor-condenser unit located at the 8L0-ft elevation. Two 5-ton Trane Company '"Climate Changers", located at the 852- ft elevation, air condition the office areas. 20.9 Fire Protection System The entire Building 7503 area, with the exception of the shielded cells, the switch house, the fan house, and the battery room, is pro- tected by a Grinnell Company water sprinkler system installed as part 510 Unclassified ORNL DWG 64-9109 From Roof Dreins \.I , Jr— e ——-l/—'/ E 32733.29 =X | —8-in. Drain From l ' ,( Cell Annulus Building 7503 Sump /‘- -| I Reactor ' 3% in. Cell L -~ | / \ 4_in. Drain Tile s Footing Drain ’Ll)\\ — ] ' ) l Absorber Pit / s Mo Catch Basin 1o. Catch Basin, in. Invert Invert . N —~——f——=— 836 ft 11 in. E32660.85 843 £t 0 in. [?j E32660.18 l 12 ]:I;;iitom___’_ I g\ =) I Headwall ~ .)L mev835ft01n+ ME6T6.0 Figure 20.2. 0.85/ L / 12 in. RCP Storm Drein N1857 ] Headwall ~ /~I\ L " E 32497.0 ( E 52526.83 Elev 836 ft O in.+ 85y N.8592. 5 = Schematic Diegram Building 7503 Dreinage System w re 511 of the MSRE project. - Water for the system is obtained from the 6-in. potable water line entering the north end of the building, see Figure 20.1. A L-in. Siamese doub;e-hose connection is provided outside the north end of the building to attach a booster source of water for the sprinkler system. The 6-in. potable water main also has a 4-in. branch connection just inside the building with 4-in. shutoff and check valves, to supply six fire hose cabinets. The 4-in. hose supply can also be augmented from the booster connection outside the building. Under normal conditions the sprinkler system is valved off from the water supply, the consequences of inopportune release of water being more serious than the short delay in opening the valves if wvater is needed. ™ 513 APPENDIX ( r 1 10. 11. 12. 13. 14, 15. 16. 515 LIST OF REFERENCES USED IN PART I H. G. MacPherson, Molten-Salt Breeder Reactors, ORNL-CF-59-12-6k (Jan. 12, 1960). L. G. Alexander, et al. Experimental Molten-Salt-Fueled Power Reactor, ORNL- 27‘6'fi@arch , 1960). J. A. Swartout, Letter to R. M. Roth, Request for Directive CR-316, Molten Salt Reactor Experiment (Mar. 17, 1961). S. R. Sapirie, ARC Directive CL-262, Molten Salt Reactor Experi- ment, Bldg. 7503, Oak Ridge, Tennessee (April 28, 1961). F. F. Blankenship, Additional Estimated Physical Properties of MSRE Fuel, ORNL-MSR-63-30 (July 17, 1963). S. E. Beall, et al., MSRE Preliminary Hazards Report, ORNL-CF-61-2-46 (Feb. 28, 196'7 S. E. Beall, et al., MSRE Preliminary Hazards Report Addendum No. 1, ORNL-CF-61-2-46 (August 14, 1961). 'MSREuStaff MSRE Preliminary Hazards Report Addendum No. 2, ORNL CR-61-2-46 (May 8, 1962). W. B. Cottrell (ed.), (Classified "Secret"), ORNL-1407 (Nov. 24, 1952). W. B. Cottrell, et al., The Aircraft Reactor Test Hazards Summary Report, ORNL- 1855 (Jan. 19, 1955). R. B. Briggs, Molten-Salt Reactor Program Semiannual Progress Report for Period Ending Dec. 31, 1963, ORNL*3626. L. F. Parsley, MSRE Reactor Contaihment Vessel Design Criteria, ORNL MSR-61-70 (June 23, 196l). L. P. Parsley, MSRE COfitainment Vessel Stress Studies, ORNL MSR-62-15 (Feb. 2, 1962). L._F; Parsléy; Consequences of a Salt Spill into the Bottom of the MSRE Contelnment Vessel, ORNL MSR-62-12 (Jan, 23, 1962). R. B. Lindauer, MSRE Process Flowsheet Discussions, ORNL MSR 62-4 (Jan 10, 1962) R. B. Lindauer, Revisions to MSRE Design Date Sheets, Issue No. 8, ORNL CF-63-6-30 (June 12, 1963). References, Cont'd, 516 17. 18. 19, 20. 2l1. 22. 23, 2k, 25. 26. 27. 28. 29. 30. 3l. 32. R. B. Lindauer, MSRE Line Schedule, Revision No. 3, ORNL MSR- 63-36 (Oct. 14, 1963). E. H. Bettis (ed.), MSRE Component Design Report, ORNL MSR-61-67 (June 20, 1961). W. B. McDonald, Fabrication Specifications, Procedures and Records for MSRE Components, ORNL MSR-62-3 (Jan. 23, 1962). A. L. Boch, et al., The Molten Salt Reactor Experiment, paper pre- sented at Internatlonal Atomic Energy Symposium, Vienna, Austria, Oct. 23-27, 1961. Contract, National Carbon Company, No. AT(40-1)-2882, Requlsltlon No. 61- 2189 (July 1%, 1961), and Order No. OR62- 17&6 Requisition No. 62-1723 (June 1h 1962). R. B. Briggs, et al., Modifications to Specifications for MSRE Graphite, ORNL CF'EB 2-18 (Feb. 1L, 1963). H. G. MacPherson, Memo to A. M, Weinberg, Graphite Problems in the MSRE, (Nov. 25, 1960). R. C. Schulze, et al., INOR-8-Graphite-Fused-Salt Compatablility Test, ORNL- 312M_TJune 1, 1961). W. H. Cook and A. Taboada, Oxygen Contamination in the MSRE from Graphite and INOR-8, ORNL MSR-62-3C (May 10, 1962). S. E. Beall, Procedures for Cleaning and Purging MSRE Graphite, ORNL MSR-61-148 (Dec. 11, 1961). I. Spiewak, Proposed Program for Purging and Cleaning MSRE Graphite, ORNL MSR-61-14L4 (Dec. 4, 1961). B. W. Kinyon, Effects of Graphite Shrinkage in MSRE Core, ORNL CF- 60-9-10 (Sept. 2, 1960). S. E. Moore, Memo to R. B. Briggs, MSRE Core Graphite Shrinkage, April 26, 1962. W. L. Breazeale, Preheating of Graphite Core in MSRE, ORNL MSR~61-99 (Aug. 15, 1961). J. R. Engel and P. N. Haubenreich, Temperatures in the MSRE Core During Steady-State Power Operation, ORNL TM-378 (Nov. 5, 1962). R. Van Winkle, Temperature Rise in the MSCR Graphite Due to Decay Heat from Absorbed Fuel Salt - MSCR Memo No. 4, ORNL CF-61-9-59 (Sept. 25, 1961). R 7 4 Ca References, Cont'd. 517 33. 3k, 35. 36. 31 38. 29. 4o. 4. ho, L3, Ly, 45. L6. 47. L8. J. H. Crawford, E. G. Bohlman and E. H. Taylor, Report of the MSRE Graphite Committee, ORNL CF-61-1-54 (Jan 16, f9617“‘""' L. F. Parsley, MSRE Core No. 1 Design Justification, ORNL CF- 60-9-89 (Sept. 28, 1960). H. F. Poppendiek and L. D. Palmer, Forced Convection Heat Transfer Between Parallel Plates and Annuli with Volume Heat Sources within the Fluids, ORNL-1701 (May 11, 195L4). L. F, Parsley, Letter to A. L. Boch, Temperature Rise Effects in MSRE Cores with Round and Flat Fuel Channels (June 10, 1960). J. E. Mott, Hydrodynamic and Heat Transfer Studies of a Full-Scale Reentrant Core (HRT), ORNL CF-58-8-54 (Aug. 8, 1958). R. J. Kedl, Pressure Drop Through the MSRE Core, ORNL MSR-62-T71 (Sept. 5, 1962). R. J. Kedl, Salt Flow Rate Through Core Support Flange, ORNL MSR- 6=k (Jan. 24, 196L). R. B. Briggs, Molten-Salt Reactor Program Semiannual Progress Report for Period Ending Aug. 31, 1962, ORNL-3369 (Dec. &, 1962). R. J. Kedl, Holes for Starved Fuel Channels in the MSRE Core, ORNL MSR-63-6 (Feb. 21, 1963). R. D. Sterling, Letter to E, S. Bettis, Review of MSRE Electrical povwer System, Bldg 7503 (Nov. 3, 196l1). J. A. Westsik, Drain.Tsnk Capacity Requirements for MSRE, ORNL MSR-61- lhl (Dec 5, 1961) H. R Payne, Mechanical Design of the MSRE Control Rods and Reactor Access Nozzle, ORNL MSR-61-158 (Circa, June, 1961). C. W"Nestor;'Jr:; Prelimihary Calculations of Heat Generation and Hellum.Production in.MSRE Control Rods, ORNL, MSR-61-118_(Sept 26, 1961). P. N Haubenreich Importance of Errors in Measurement of Tempera- ture and Control Rod Position in.MSRE, ORNL CF~63-8-43 (Aug 14, 1965) "Unfired Pressure Vessels", Section VIII, ASME 301ler and Pressure Vessel Code, American Society of Mechanical Engineers, New York. (See text for edition date, 1f importaunt). "General Requirements for Nuclear Vessels, Case 1270N", Interpretations of ASME Boller and Pressure Vessel Codes, American Society of Mechanical Engineers, New York. (See text for revision number). References, Cont'd. 518 kg, 50. 51. 52. 53. 5k, 25 56. 2. 58. 29. 61. 62, 63. 6L, "Containment and Intermediate Containment Vessels, Case 1272N", Case Interpretations of ASME Boiler and Pressure Vessel Codes, American Society of Mechanical Engineers, New York. (See text for revision number). "Nuclear Reactor Vessels and Primary Vessels, Case 1273N", Case Interpretations of ASME Boiler and Pressure Vessel Codes, American Society of Mechanical Engineers, New York. (See test for revision number) . "Special Equipment Requirements, Case 1276N", Case Interpretations of ASME Boiler and Pressure Vessel Codes, American Society of Mechanical Engineers, New York. (See text for revision number). - "Nickel-Molybdenium-Chromium-Iron Alloy, Case 1315", Case Interpre- tations of ASME Boiler and Pressure Vessel Codes, American Society of Mechanical Engineers, New York. (See test for revision number), R. W. Swindeman, Design Stresses for Wrought and Annealed INOR-8 Between Room Temperature and 1400°F, ORNL MSR-60-31. W. L. Breazeale, Gamma Heating of Reactor Vessel Hanger Rods for MSRE, ORNL MSR-61-27 (Mar. 21{, 1961). W. L. Breazeale, Re-evaluation of Gamma Heating in Proposed Reactor Vessel Hanger Rods for MSRE, ORNL MSR 61-52 (May 12, 1961). J. H. Westsik, Memo to R. B. Briggs, Review of Flow Design to the MSRE Thermal Shield (July 23, 1962). W. C. Ulrich, Memo to S. E. Beall, Loss of Cooling Water Flow to the MSRE Thermal Shield (Feb. 20, 1963). E. C. Miller, Memo to F. L. Rouser, MSRE Reactor Vessel Thermal Shield Drawings E-KK-D-L0722 - LO730 (May 8, 1962). H. C. Claiborne, High-Energy Neutron Flux in the Containment Vessel of the MSRE, ORNL MSR-62-27 (March 19, 1962). P. G. Smith, Water Test Development of Fuel Pump for the MSRE, ORNL ™-79 (Mar. 27, 1962). General Alloys, Boston, Mass., Purchase Order No. T4Y-L7524 (July 11, 1962). Lukins Steel Company (Coatesville, Pa.), Purchase Order No. 93Y-87622, October 30, 1961, Westinghouse Electric Corp., Purchase Order No. 63Y-57698, May 29, 1961. Specification of Drive Motor for MSRE Primary Pump, ORNL Job Specification 169-101 (Mar. 15, 1961). * ¥ . g;;_fi ¥ i LW References, Cont'd. 519 65. Specification for Drive Motor for MSRE Secondary Pump, ORNL 4 Job Specification 169-124 (Oct. 11, 1961). 66. A. G. Grindell, et al., Memo to E. S. Bettis, Design Memo for MSRE Pumps (Dec. 15, 1961). 67. Ralph H. Guymon, Memo to R. B. Brlggs, Fuel and Coolant Pump 0il Systems (Jan. 15, 1963). 68. A. G. Grindell, Back-Diffusion Experiment on PK-P Pump, ORNL MSR-61-50 (May 11, 1961). 69. G. H. Llewellyn, Gamma, Beta and Neutron Heating of MSRE Pump Lubrication Shield, ORNL CF-61-1-36 (Jan. 16, 1961). 70. C. W. Nestor, Influence of Residence Time Distribution of Fission- Produc¢t Decay in the MSKE Pump Bowl and Off-Gas Line, ORNL CF 61-6-85 (June 23, 1961). TL. 1. Spiewak, Xenon Removal in the MSRE Pump Bowl, ORNL MSR-60-8 (Oct 7, 1960) . 2. 8. J. Ball MSRE Pump Gas Purge System Study, ORNL MSR-61-3 (Jan. 9, 1961) 73. P. H. Harley, Pump Bowl Overflow Line, ORNL MSR-62-2 (Jan. 10, 1962). 74. C. H. Gabbard, Air Cooling Requirements of MSRE Primary Pump Bowl, ORNL MSR-61-28 (Mar. 25, 1961). 75. C. H. Gabbard, Electrical Insulation for the MSRE Fuel and Coolant Pump Drive Motors, ORNL MSR-62-10 (Feb. 1, 1962). 76.'_:D W. Vroom, Primary Pump Motor Background Radiation Level at 10-Mw, ORNL MSR-61-49 (May 10, 1961). | \ 77.g A, G. Grindell, Specification. of a Lubrlcant for MSRE Pumps, " ORNL MSR 60-37 (Nov 18, 1960). | 78. L. V, Wllson, MSRE Fuel Pump Coolant 0il Temperature After - " Cessation of 0il Flow, ORNL MSR 61-84 (July 28, 1961). . 79. C. H. Gabbard, Estimated Flow Startup Trensient of the MSRE Fuel 8 stem, ORNL MSR 6l1- 153 (Nov. lh l§61) - 80. -R. B. Briggs Molten-Salt Reactor Program Progress Report for - Period from August 1, 1960 to February 23, 19601, ORNL-3122 (June 20, 1961). References, Cont'd. 520 * 8L. A. G. Grindell and P. G. Smith, MSRE Prototype Pump Shaft Seizure, ORNL MSR-62-67 (Aug. 27, 1962). 82. D. E. Gladow, MSRE Primary Pump; Analysis of Stress in Impeller Bowl Due to Axial Loading, ORNL MSR-60-60 (Sept. 3, 1960). 83. T. B. Fowler, Generalized Heat Conduction Code for the IBM 7090 Computer, ORNL CF-6l-2-33 (Feb. 9, 1961). | 84, ©F. J. Stanek, Stress Analysis of Cylindrical Shells, ORNL - CF-58-9-2 (July 22, 1959). > 85. F. J. Stanek, Stress Analysis of Conical Shells, ORNL CF-58-6-52 (Aug. 28, 1958). | | C 86. F. J. Witt, Thermal Stress Analysis of Cylindrical Shells, ORNL CF-59-1-33 (Mar. 26, 1959). 87. ©F. J. Witt, Thermal Analysis of Conical Shells, ORNL CF-61-5-61 (July 7, 1961). 88. C. H. Gabbard, Thermal-Strain and Strain-Fatigue Analyses of MSRE Fuel and Coolant Pump Tanks, ORNL TM-7¢ (Oct. 3, 1962). 89. R. B. Gallaher, Thermal Stress Analysis of the Sampler-Enricher Attachment to the MSRE Fuel Pump, ORNL MSR-62-16 (Feb. 5, 1962). 90. W. C. Ulrich, Fuel Pump Main Support Members, Memo to R. B. Briggs, ORNL M83451 =159 (circa June, 1961). E ol. J. M. Corum, Memo to R. B. Briggs, Flexibility.Afialysié of B MSRE Piping, April 24, 1962. 92. Specification for Primary Heat Exchanger for MSRE, ORNL Job > Specification 80-109 (Dec. 22, 1960). 935. Tentative Specification for Fabrication of MSRE Heat Ekchanger Tube Bundle, ORNL Job Specification ©1-152 (Sept. 10, 1962). 9. Specification for Brazing of the Tube Bundle for the MSRE Heat Exchanger, ORNL Job Specification d0-167 (July 16, 1962). 95. R. G. Donnelly, Requirements for Welding Tube-to-Tube Sheet Joints for MSRE Primary Heat Exchanger and Heat Exchanger Sample, ORNL MSR-62-66 (Aug. 29, 1962). 96, R. G. Donnelly, Primary Heat Exchanger Tube-to-Tube Sheet Welding and Subsequent Machining, ORNL MSR 62-39 (May 16, 1962). ~ e oT. R. G. Donnelly, Design Revisions for the Primary Heat Exchanger Tube- \‘J to-Tube Sheet Joints, ORNL MSR-62-23 (March 1, 1962). " o/ 1Y .L;j References, Cont'd. 521 98. R. G. Connelly, Brazing Alloy for the Primary Heat Exchanger Tube- to-Tube Sheet Joints, ORNL MSR-62-6 (Feb. 12, 1962). 99. W. C. Ulrich, Hydrostatic Test Pressures for MSRE Primary Heat Exchanger, Memo to C. K. McGlothlan, March 12, 1963. 100. J. C. Amos, R. E. MacPherson and R. L. Senn, Preliminary Report of Fused Salt Mixture 130 Heat Transfer Coefficient Test, ORNL CF-58-4-23 (April 2, 1958). 101. D. Q. Kern, Process Heat Transfer, p. 834, Figure 2k, McGraw-Hill; New York, 1950. 102. G. T. Colwell, Pressure Drops Through MSRE Heat Exchanger and Piping, Memo to R. B. Briggs (Aug. 29, 1962) . 103. Standards of Tubular Exchanger Manufacturers Association, TEMA, 366 Madison.Ave., New York, 1949, 104, H. R. Payne, Reservoir for Fuel Salt Drain Tank Coollng System, Addendum to MSR 61-67 (Ref. 18), Memo to Distribution (July 11, 1961). 105. J. C. Moyers, Design of Freeze Valves for MSRE, ORNL MSR 61-160 (Circa, June, 1961). 106. American Standard Code for Pressure Piping, ASA B 31.1 - 1955, American Society of Mechanical Engineers, New York. 107. W. C. Ulrich, MSRE Pipe Support Calculations by R. E. Ramsey, Memo to R. B. Briggs, (Jan. 28, 1965) 108, R. B. Briggs, Molten-Salt Reactor Program Semiannual Progress Report for Period Ending Aug. 311 1962, ORNL-3369 (Dec. 4, 1962). 109. J. c. Moyers, Thermal Cycling Test of 3- -1/2- in. and h—ln Freeze Flanges, ORNL CF- 61 2 58 (Feb 2, 196—) 110. R. B. Brlggs, Molten-Salt Reactor Program Semlannual Progress Report ' _F;for Period Ending Jan. 31, 1963, ORNL-3%419 (May 24, 1965) 111. J. C. Moyers, Design of Freeze Flanges for MSRE, Memo to R. B. ~ Briggs, ORNL MSR-61-101 (circa June, 1961) 112. R. E. Ramsey (Burns and Roe), MSRE Reactor Plping Stress Analysis, ~© . Memo to R. B. Brlggs, ORNL MSR—61 157 (circa, June, 1961). '115; Sturn-Krouse, Inc., Research and Consulting Engineers (Auburn, Alabama), Analyses and Design Suggestions for Freeze Flange Assemblies for MSRE, Report to ORNL under Subcontract No. 1477, Nov. 30, 1960. References, Cont'd. 522 114. M. Richardson, Development of Freeze Valves for Use in the MSRE, ORNL Tm-128 (Feb. 28, 1962). 115. R. B. Briggs, Operation of Freeze Valves in the MSRE, ORNL MSR-63-47 (Dec. 12, 1963). 116. R. L. Moore, MSRE Freeze Valve Control Circuitry, Memo to Distribution (May 31, 1962). 117. R. B. Briggs, Molten-Salt Reactor Program Semiannual Progress " Report for Period Ending July 3L, 1963, ORNL-3529 (Dec. 30, 1963). '118. W. Thomas Mullins, Activation Analysis of Heater Materials (for MSRE), Memo to M. Richardson (Oct. 16, 1962). 119. J. R. Engel and B. E. Prince, Criticality Factors in MSRE Fuel Storage and Drain Tanks, ORNL-TM-759 (In preparation). 120. Status and Progress Report, Oak Ridge National Laboratory, p. 15, ORNL-3543 (Nov., 1963). 121, R. E. Thoma and F. F. Blankenship, Relative Abundance of Phases in the Frozen MSRE Fuel at Equilibrium Conditions, ORNL MSR (Revised) 63-36 (Nov. O, 1963). 122. S. E. Beall, et al., MSRE Reactor Safety Analysis Report, ORNL T™™-732 (August, 1964). 123. T. W. Pickel, MSRE Drain Times, ORNL MSR-62-97 (Dec. 17, 1962). 124, L. F. Parsley, MSRE Drain Tank Heat Removal Studies, ORNL CF-60-9-55 (Sept. 19, 1960). 125, Vapor Condensing System Water and Gas Tanks, ORNL Specification XSP-120 (April 27, 1964). 126. P. H. Harley, Drain Tank Furnace Tests, ORNL MSR 64-9 (Feb. 2L, 196k). 127. H. R. Payne, Weights of MSRE Fuel, Flush and Coolant Tanks, and Contents, Memo to R. L. Moore (Jan. 29, 1962). 128. R. B. Gallaher, MSRE Sampler-Enricher System Proposal, ORNL CF-61-5-120 (May 24, 1961). 129. G. A. Cristy, Stresses and Loads in the Sampler-Enricher Transfer Tube, Work Request A-T0496-11D, Letter to E. S. Bettis (Nov. 13, 1961). 130, C. H. Gabbard, Hydraulic Performance of MSRE Coolant Pump, Memo to A. G. Grindell (July 9, 1963). ry .|( T4 e & ks, "* MSR 61-83 (July 27, 1961). References, Cont'd. ‘ 523 151. 132, 133. 13k, 135. 136. 137, 138. 139. 140. 141 . 1ho, 143, 1k, 146, 1L7. 148. W. C. Ulrich, MSRE Radiator Design, ORNL CF-60-11-108 (Nov. 30, 1960). Roy C. Robertson and S. E. Bolt, MSRE Heaters - Summary of Pre- liminary Studies, Memo to E S. Bettis (Aug. 11, 1960). W. B. McDonald, Insulation of Thermocouples on.MSRE Radiator, Memo to R. B. Briggs (Feb. 5, 1963). W. C. Ulrich, Hydrostatic Test Pressure for MSRE Radiator, Memo to C. K. McGlothlan (April 9, 1963). W. C. Ulrich, MSRE Radiator Air Flow Characteristics, ORNL MSR 61-18 (Mar. 8, 1961). W. C. Ulrich, Control of Heat Removal Rate from MSRE Radiator, ORNL, MSR 61-51 (May 12, 1961). - S. J. Ditto, Control of MSRE Between 1 Mw and 10 Mw, ORNL MSR 63-23 (June 4, 1963). S. J. Ball, Freezing Times for Stagnant Salt in MSRE Radiator Tubes, Memo to § R. Tallackson (April 9, 1963). R. E. Ramsey (Burns and Roe), Coolant System Stress Analysis, Memo to R. B. Briggs, ORNL MSR-61-156 (Nov. 3, 1961). A. N. Smith, MSRE Cover Gas System, ORNL MSR 60-44 (Nov. 30, 1960). A. N. Smith, MSRE Cover Gas System Flowsheet, ORNL MSR 60-11 (Oct. T, 1960). P. N. Haubenreich, Oxygen Production by Fluorine 19 (n, ) Reactlon in MSRE, ORNL MSR-64.23 (May 27, 1964). - A, N. Smith MSRE Cover Gas System, De51gm.Memo C-3, Helium Dryer, Memo to R. B. Briggs (Nov. , 1961). A. N. Smith Helium Surge Tank, Design Memo C- 4, Memo to R.. B. Briggs (Nov. 10, 1961) A, N, Smith, Lesak Detector System, MSRE Cover Gas System, ORNL P. P. Holz, Development of Six—Station Manifold Disconnect ORNL CF-6 - | -117 (May 18, 1961). 1-5- P. P Holz, Status of Small Pipe Disconnects for'MSRE, ORNL CF-60-9-102 (Sept. 27, 1960). A . N. Smith, MSRE Charcoal Beds, ORNL MSR-61-101 (Aug. 17, 1961). References, Cont'd. 524 149, R. B. Stevenson, Radiation Source Strengths in the Expansion and Off-Gas System of the ART, ORNL CF-57-7-17 (Nov. 18, 1957). 150, J. 0. Blomeke and M. ¥. Todd, Uranium 235 Fission-Product Production as Function of Thermal Neutron Flux, Irradiation Time, and Decay Time, ORNL-2127, Part I, Vol. I (Aug. 19, 1957). 151. Solenberger, et al., Treatment of Off-Gas from the HRT, KT 373, Memo to W. E. Browning, Jr. (Nov. 1%, 1958). 152. R. D. Ackley and W. E. Browning, Equilibrium Adsorption of Kr and Xe on Activated Carbon and Linde Molecular Sieves, ORNL CF-61-2-32 (Feb. 14, 1961). 153. Fire Resistant High-Efficiency Air Filter - up to 250°F, ORNL Specification XSP-26. 15k, Design Criteria Containment and Building Ventilation System, Building 7503, ORNL Work Request A-704Q96-11D (Jan. 28, 1963). 155. F. L. Culler, Criteria for Handling Melton Valley Radioactive Wastes, ORNL CF-6l-5-24, May 3, 196l and Supplement No. 1, May 12, 1961. 156. W. C. Ulrich, Overall Heat Transfer Coefficient for Treated Water Cooler, Memo to S. J. Ball (April Lk, 1963) 157. S. J. Ball, Analysis of MSRE Cooling Water Temperature Control, Memo to R. L. Moore (May 2, 1963). 158. Closed Cycle Pressure Drop, MSRE Water System, ORNL P & E Division Design File, Sept. 22, 1961. 159. Cooling Tower Load, MSRE Water System, ORNL P & E Division, (No date). 160. J. C. Moyers, Requirements for MSRE Valves and Flanges, Letter to L. F. Parsley (April 19, 1961). 161. L. F. Parsley, MSRE Simultaneous Salt and Water Spill Accidents, ORNL, MSR-61-120 (Sept. 28, 196l1). 162. A. N. Smith, Secondary Containment for the Off-Gas Lines, ORNL MSR-61-110 (Aug. 30, 1961). 163. L. F. Parsley, Theoretical Analysis of Certain Penetration Regions of the MSRE Containment Vessel, ORNL MSR 61-96 (Aug. 10, 1961). 164, L. F. Parsley, MSRE Containment Vessel Stress Studies, ORNL MSR-62-15 (Feb. 2, 1962). (™ 1) ”m References, Cont'd, 525 2 165. L. F. Parsley, Design'of Pressure-Suppression System for the MSRE, Memo to R. B. Briggs (Oct. 17, 1961}. 166. R. B. Briggs, MSRE Pressure-Suppression System, ORNL MSR-61-135 (Nov. 15, 1961). 167. F. R. Bruce, ORNL Radiationnand Safety Control Manual, June 1, 1961. 168. H. C. Claiborne, Review of the MSEE Blologlcal Shielding, ORNL < MSR-63-17 (May 13, 1963). 5 169. D. W. Vroom, MSRE 0ff-Gas Line and Charcoal Bed Shielding Re- quirements During Operation, ORNL CF-61-10-57 (Oct. 23, 196l1). v 170. D. W. Vroom, Preliminary MSRE Gamma Ray Source and Biological 5 Shielding Survey, ORNL CF-61-4-97 (April 28, 1961). 171. A. N. Smith, Shielding of Off-Gas Lines, ORNL MSR-61-125 (Oct. 29, 1961). 172. Allis-Chalmers Co. Instruction Manusl and Parts Catalog, Buda Division, Model DC SG-3%00-A%E Generator, Allis-Chalmers 8DCSG-2505 Diesel Engine, for Union Carbide Nuclear Co., Contract No. W8X-18089. 175. Electrical Storage Battery Company, Exide Industrial Division, Instruction Manual, Installing and Operating Exide Batteries, Form 4676, 6th ed. fi 17h. Electrical Products Company, Instruction Manual for Installation ) Operation and Maintenance of Diverter-Pole Motor-Generators ’.,J s 5 SM-1050 (Feb. 1, 1950). a ' L75. Reliance Electric and Engineering Company, Instructlon Book, ' 250-v, . 25 kva, Motor-Generator Set, Book No. 819541 (Feb., 1962) 176. T. E. Nbrthup, MSRE Vapor Conden31ng System - Parallel Rupture Discs, Memo to R. G Affel, May 28, 196h 526 ARBREVIATIONS The following ebbrevietions heve been used in the Description of the Reector Design, Part I, ORNL-TM-728: alternating current AC Americen Institute of _ AIEE Electrical Engineers o smphere emp Americen Society of Mechanicel Engineers ASME asymetrical asym awxiliary : gux Brinell hardness aumber - Bhn breke horsepower bhp British thermsl unit Btu Centigrade, degrees °C cubic centimeter ce centimeter cm constant, valve (flow coefficient) c diameter ' ~ diam direct current nC distribution _ distr drawing Dwg east E electramotice force emf elevation elev Fehrenheit, degrees °F feet per second fps feet £t gellon gel * Now the Institute of Electricel and Electronic Engineers, IEEE. L " (W oy 527 gellons per minute hegter .~ - horsepower hour inches inside dlsmeter instrument interupt current iron pipe size kilogrem kilowatt kilovolt kilovolt -smphere liter phase pounds pounds, force meximum mills, 1,000 circular minimum roentgen equivelent man, x 105 Molten Salt Reactor Experiment megawett : - ' National Electrical - Manufacturers Associstion ndminal pipe size neufrons . nbf%h nuzber | Oek Ridge Nationel Lsboratory opefated - outside dleameter pages panel htr in. instr IC No. ORNL oD pnl 528 parts per million pounds per in.a, ebsolute pounds per in.a, gege pover factor radietion, ebsorbed dose reference ' revolutions per minute reactivity reactivity chenge receptacle roentgen roentgen equivalent man rocm root mean square schedule second gouth stalnless steel stendard cubic feet per minute standard tempersture and pressure switch switchgear Tennessee Velley Authority thermocouple transfer transformer unified national coarse thread universel gas constant volt watt west psia psig rad ref recept rem sched sec SS scfm Vg TVA TC Xfer s ® <4 W Y ‘_m a'y 529 FQUIPMENT AND LOCA'I‘ION A'BBREVIATIONS (FDT) Note: Several changes were made in the ebbreviations es the MSRE design progressed. Since the reference literature and draw- ings make use of some of the old notations, &ll of the ebbrev- iations have been included in th:l.s listing, but with those considered o'bsolete inclosed in parenthesis. Some duplications exist, .but in such" caeses the context in which the ebbreviation is used will make the choice of meanings evident. AB Amcilia.ry Boa.rd | ~CR. Coolant ‘Redistor ABC Absorber: Cu'bicle __ . -GS Ceustic Scru'b‘ber (AC) Avsorber Tubicle, (c8) Conteimment Steck AC Air Cmpréssof, x,2 . - CST . Condensate Storage Tank, l, ACB Auxiliary Charcoal Bed (Cell) CSS Coolent Selt Sempler AD-1 Inlet Air Duct to Rediator - CT Cooling Tower | AD-2 Radia.tor By-Pess Duct - CTP Coolins Tower Pup, l, AD-3 Exit Air Duct from Radia.tor . CTW Cooling Tover Water | and Coolent Stack CTWR Cooling Tower Weter Return AD Instrmnent' Alr Dryer, 1, 2 (DB) Duct Blower (AR) Auxiliery Rocm - D¢ Decontemination Cell Bi. Blower House -- - . DCC Drain Cell Cooler (BWT) Weste Tank Vent Blower DE Diesel House | C-1 30-Tom Creme - DP Diesel Panel €-2 10-Ton Creme . = pDPI Diesel Penel, Switch House €5 5-Ton Creme = -~ - DPM Diesel Panel, Aux. Control Rm. CAP Contaimment Air Pa.nels o DR Cover Gas Dryer, 1, 2 CB Charcoel Bed, 1A, 1B; 24, 2 b peconteminetion Cell CEC _Charcoal Bed Cell . | ~ (pIC) Drain Tenk Condenser ‘."? : Coolent Cell 7 | e Drain Tank Cell CCC Coolent Cell Cooler,qE, W " ENS Eumergency Nitrogen Station CCP Component Cooling Pmnp, 1,2,3 ESA Electric Service Area CDC Coolemt Dfeim Cell'™ pgs prusoment Storage Cell CDT Coolant Drain Tank (ET) East Tunnel | GG Cover Ges’(Panel) F Stack Filter, 1, 2, 3 COP Coolent Pump Lnbe 011 Pump, 1,2 FD Fuel Drain Tamk, 1, 2 CP Coolant Pump Fuel Dreain Tank, 1, 2 530 FF Freeze Flange (Five) MB FFT Fuel Flush Tank : MB-1 (FE) Blower House MB-3 FLP F, Preheater . FIR F, Reactor | | MOG FOP Fuel Pump Lube 0il -Pmnp, 1,2 MCCT FP Fuel Pump MCR FPC Fuel Progessing Cell (MCR) FPS Fuel Processing Sempler RMCR (FS) Fuel Sempler (FSC) Fuel Storsge Cell MG FST Fuel Storage Tank MG-1 FV Freeze Velve (Twelve) MG-2 FWT Feed Water Tank, 1, 2 MG-3 GC Gas Cooler (Component MG-k Cooling System) e (GCP) Gas Coolant Pump (Component (M5) Cooling System) 1, 2 GOP Cas 01l Pump (Component NP Cooling System) 1, 2 OBE HB High Bay ' OBS HCP Heater Control Panel oC (ap) Helium Dryer, 1, 2 (OCR) HDP Hester Distribution Panel oCcT He Treated Helium Surge Tenk OF HeF Fresh Helium Supply Trailer OFT (EH) Helium Preheater (OFT) HP Heater Panel OR BX (Primary) Heat Exchanger oT (IAD) Instrument Air Dryer, 1, 2 PH IF Inlet Filter (High Bey Area) FPIW LD Leek Detector ’ FP (LKD) Lesk Detector ' PR (LOP) Lube 0il Package | (PT) (IWT) Liquid Waste Tenk R M Motor R-1 Main Board Main Blowers to Coolant Rediator : Annulus Blowers to Coolant Radiator Ducting Motor Control Center Motor Conmtrol Center, TVA Main Control Room Maintenence Control Room (Remote) Maintenance Control Room Motor-Generator 250-v Motor-Generator Set = 48-v Motor-Generator Set | 48-v Motor-Generetor Set 25-kva Motor-Generator Set Maintenance Practice Cell Main Sump (Pump) Room Ruclear Psnel Outside Building, East Outside Building, South 0il Cooler, 1, 2 (Operating) Main Control Room ] 0il Catch Tank, 1, 2 0il Filter, 1, 2 Fuel Pump Overflow Tank 0il (Fill) Supply Tank Oxygen Removel Unit, 1, 2 0il Supply Tenk, 1, 2 Cover Ges Prehester, 1, 2 840-ft Elev Passage, W Side Pit Pump Punp Room Process Weter (Storage) Tenk Reactor “ ¢ Instrument Air Receiver - Ty A 531 R-2 Instrmnent- Air Receiver TWP Treated Water Pump R-3 Service Air Receiver VE Vent House RC Reactor Cell _ VH-1l Volume Holdup Inside RC RCC Reactor Cell Cdolgr o VH-2 Volume Holdup in CBC RDB Rediator Door Breke VP Vacuum Pump RDC Radiator Door Clutch VT Vapor Condensing Tank, 1, 2 RDM Radiator Door Drive Waste Blower RMC Remote Maintensnce Cell Waste Filter S-1 Contairment (Off-Ges) Stack WOR Waste Oil Receiver, 1, 2 5 & SC Spare Cell WP Waste Pump (sc) Stesm Condenser WR Water Room SD Steem Dome (Drum) on FD = WI Liquid Waste Tank SDC Steem Dome Co:idetiser , 1,2 WI West Tunnel | SE Sempler-Enricher WIC Waste (Tank) Treatment SER Special Equipment Room Cell, or Liquid Waste Cell SF Stack Fan, 1, 2 (SPA) Stack Filter (Fan) Arvea SFA Sodium Fluoride Absorbers SFT Sodium Fluoride Trap SH Switch House - | | SOP 502 Prehesater SP Sump Room, A, B SR Solenoid Rack SR Service Room ST Surge 'J;fanlc ST Service Tunnel SV Sempler-Enricher Vacuum Pump (TC) Transfer (Spare) Cell TF (Cooling) Tower Fan, 1, 2 TR Transmitter Reck (Room) TRM Transmitter Room TS Thermocouple Scanner T™WC Treated Water Cooler s e e g - ¢ 532 | | a ‘ - o Unclassified ! ) -t | o ' ORNL DWG 64-9110 " I * | . A s|22>2222> , 23> >>2>3>>>> | MEPATMS A1 B8 U2 s e EeE R LOCALLY MOUNTED (AT OR NEAR PROCESS) | ' ‘ | AR EEEEEEREEEEEEEER, | - Yumghisgog v | @ O 6 W L T ¥ J o ¥ 3 = > F X N ‘ ' v Q O O L U I I O O O ¢ LU QO L L O ‘ , ? sjosuonaepodey | € 2 & ¢ x | | ¥ @ ¥ ¢ ¥ ¥ & € ® PANEL MOUNTED (ON PANEL NO. XX) F XN | ' | i XX = R soiuupag doio2tPul B | T 5 3 @ R £ I S o & s F > E XN - MECHANICALLY COUPLED (PLUG-IN CONTROL, THERMOCOUPLE ; syposorozpyy 2| £ F 2 2 22 | 2 2 2 2 2 2 = 2 = '’ afl% v:su., TWO-PEN RECORDER OR INDICATOR, OR RECORDER 1 | | : NTEGRAL SWITCH, ETC. rorons s |lYuvuvuu LU ULY LYY ! flodduog dojodip¥] = | T T o W L T ''J o & B > F XN | | oAloA Pojjouuon Ajsiowsy = | O O O O O 5 ' 30050000 o ¥ , fl DESIGNATION OF ANNUNCIATOR (UNIT NO. XX~-POINT NO. X) i Vi< oO0Oowux ! liae&eaear > xN ANN XX-X ol 900000 [ 0 00¢g©0©0O0OCO0 ; | 40j0s0d() pe|josuor) Ajsjowey O 2 8 8 8 h’. %:, 1 3 g ‘txJ g E L>) L;) g g INTERMEDIATELY MOUNTED (BETWEEN MAIN PANEL AND PROCESS) i ' wew = (0 PP PP HEL R (ON AUXILIARY PANEL NO. X, IF PANEL MOUNTED) | | j X SAIDA poipiedg ol P22 0> s> ; *II'"‘“’W“!I'S I I t uw X I 4 Q 1 b= [ 1 PURGE STATION NUMBER XX (3%-IN. DIAM; SEE SEC 6 FOR RECOMM : sepqwsuosy = | E O B = = e e e e NUMBERING SYSTEM) " v ENDED L < Cowuw i }ide - S E XN ‘ wims w | 2 8 BB L 2wl 2yRLERR : { ; oz o o ooz @ | & o © K ¥ ¥ &« AIR SUPPLY TO INSTRUMENT COMPONENT (¥ ,+IN. DIAM) ! @ wpro>oy @ | 2 Cowuw 1t ¥ o & K>FE XN | | pemen ey o | | L 1@ E tellglllgg . LEADS TO ELECTRICAL CONTROL CIRCUIT (ON DRAWING NO. XX) e~ CECC XX N , | < mypw x| 3332 E ) I 3FE3EEER i : . | PROCESS ELECTRICAL POWER {ON DRAWING NO. XX) : ----- F XN 3 . | - : y | 3 | fl ‘ Qo ! 1 1 1 ! | | o9 of { { J TRV PSPV - SPECIFIC IDENTIFICATION | LETTERS SECOND LETTER wewery w | W oW oMWW |l RYREYERN FIRST LETTER THIRD LETTER Pwe> 0| QY gL R EYRRYYRN Y ' ; SYMBOL(/Z{IN.‘DIA) wioly <« 5 6 3 5 o § < j n‘. = 3 lS ; ; N N : INSTRUMENT IDENTIFICATION NUMBER : | i . < U 0 W W X o Jd 0 & v = > ¥ X N { | £33 22 .4 £S5 25 FZF _ s 6Tt 5 " g & ¢ - = 3 - o w X 0 - y 2 < > 9% % % 39 2% & 2 %Y e 8 %% = “ > : 5 5 ¢ 9 5 38 3 83 s E sy o8 ° < U0 WwISEJeed k> aa Figure A.l Symbols Used on MSRE Process Flowsheets ' ‘~) | - 4 - 533 PROCESS LINES PRIMARY LIQUID LINE SECONDARY LIQUID LINE PRIMARY. GAS OR VAPOR LINE - ‘ - SECONDARY GAS OR VA?OR LINE - - ELECTRICAL POWER LINE INSTRUMENT LINES CONNECTION TO PROCESS - AIR OR PNEUMATIC SIGNAL LINE e HYDRAULIC LINE S A’ (FILLED SYSTEM) CAPILLARY TUBING X X——X ELECTRICAL SIGNAL OR CONTROL LINE INSTRUMENT OR PROCESS LINE JUNCTIONS OR CROSSOVERS SOLID DASHED LINE JUNCTION LINE CROSSOVER TWO-WAY <= THREE-WAY —Qg}— FOUR-WAY | | —%— RUPTURE DISC -—l%l— RELIEF OR SAFETY EXCESS-FLOW VALVE -ow— CHECK ==\ ;- | MANUALLY OPERATED | w>mhfiw * PEGE W. .- A. Cristy . L. Crovley . G. Davis . H. DeVan m@p;mmm C. A, Conlin b ey b9 Cy b b .. Adams . Affel Alexander Allin Anderson -Apple . Baes Ball E. Beall Bender S. Bettis F. Blankenship Blumberg L. Boch G. Bohlmann J. Borkowski R. Brashear B. Briggs L J o . H. Burger Cantor H. Chapman Claiborne H. Cook T. Corbin B. Cottrell Dirian J. Ditto G. Donnelly . A. Doss . E. Dunwoody . R. Engel . P. Epler .- Fraas - . Fray Friedman - Frye . BGabbard . Gaitanis Gallaher Geist .. Grimes 535 ORNL-TM-728 Internal Distribution | 52. 53. 54. 55. 56-65. . 66. 67. 68. 69. 70. 71. 72. 73. T4 75. 76. 77. 78. 79. 80. 81. 82. 83. &4. 85. - 86, 99. 100. -~ 301. 102, 103-108. 109. 110. 111. qhmqqmwwopmszmbszqm GHPRPDwhoaaeadmma . Giindell Guymon Hanauer Harley Haubenreich Herbert Herndon Hise Holt . Holz outzeel Hudson Jarvis . Kedl Kirslis .- Knowles . Krakoviak Krewson Lamb Lane Larson Lindauer Lundin Lyon MacPherson Martin McCurdy McDonald McDuffie . McGlothlan Metz . Miller - Mixon Moore Olson - * . Patriarca R. Payne M. Perry . B.. Piper E. Prince . L. Redford . Richardson. C. Robertson . C. Roller W. Rosenthal H. Row 112. 113. 114. 115. 116. 117. 118. 119. 120. 121. 122. 123, 124. 125. 126. 127. 128. 152-153. 154, 155. 156. 157. 158. 159-173. . . BUPLEESN YR E GO D. R. R. H. V. M. 536 W. Savage 129. G. M. Tolson W. Savolainen 130. D. B. Trauger Scott 131. W. C. Ulrich H. Shaffer 132. C. F. Weaver G. Silver 133. B. H. Webster J. Skinner 134. A. M. Weinberg F., Sliski 135, X. W. West N. Smith 136. J. C. White G. Smith 137. G. D. Whitman Spiewsk 138. H. D. Wills C. Steffy 139, L. V. Wilson H. Stone 140-142. Central Research Library J. Stripling 143-144. Y-12 Doctment Reference Section A. Swartout 145-146. Reactor Division Library , Taboada - 147-150. Laboratory Records Department R. Tallackson 151. Laboratory Records, RC E. Thoma External Distribution F. Cope, AEC, ORO W. Garrison, AEC, Washington L. Philippone, AEC, ORO M. Roth, AEC, ORO L. Smalley, AEC, ORO J. Whitman, AEC, Washington Division of Technical Information Extension, DTIE