MARTIN MARIETTA ENERGY SYSTEMS LIBR AT 3 445k 0349855 1 .@m : oz R T T UV A o N e e . ORNL-1947 f ? o This docun;rnent consists of 235 pages. iL ; e - ' _ | _ . Copy /Qé of 192 copies. Series A. ' Ifi IE Contract No. W-7405-eng-26 AlRCRAFT NUCLEAR PROPULSION PROJECT QUARTERLY PROGRESS REPORT For Period Ending September 10, 1955 W. H. Jordan, Director S. J. Cromer, Co-Director : . ' ~ R. L. Strough, Associate Director A. J. Miller, Assistant Director ‘ | ’ A. W. Savolainen, Editor El "‘:. - E ! DATE RECEIVED BY INFORMATION AND REPORTS DIVISION ; (SEPTEMBER 30, 1955) | b DATE ISSUED i 'E OCT 26 1955 b 1 OAK RIDGE 'NATIONAL LABORATORY i-. Operated by i UNlON CARBIDE NUCLEAR COMP ANY ‘ q A Dw:sron of Umon Carbide and Corbon Corporation g j’ _ ‘ k Post Offlce Box P v i ST Q»uAch Rldge,‘Telnnessee ; sfl ‘s. - % 3 445L 0349855 ] VWRONOSOL AWM — -b-.b.&AhhkwwwwwgwwwwswMMMMMMMM_.-—_..._._a_....._._..._.. CUNEWN O OVXNOUNAEWON O OVONOTUNEWOMNOCO0ONNRARWON—~O 47-48. £ 0 . N. F.Lansing . Affel . Baldock Barton Billington . Blankenship . Blizard Borkowski . Boyd . Bredig . Bruce . Callihan . Cardwell Cathcart . Center (K-25) . Charpie . Clewett . Clifford Coobs . B. Cottrell . D. Cowen ITmI>MS=00>PM-TTOV-TO® . Cromer . Crouse . Culler Dee . DeVan . Douglas . Dytko . Emlet (K-25) Feldman . Ferguson . Fraas Frye . Furgerson . Gray . Grimes . E. Hoffman . Hollaender . S. Householder . T. Howe . W. Johnson . H. Jordan . W. Keilholtz . P. Keim . T. Kelley . Kertesz . M. King - A Lane; MO OoOmMm-—map» TP rrn R C C D F E C G M F A D J Cc R G C J W D S R F. J. J D E L M D A J W H W E A A J R w G C M F E J INTERNAL DISTRIBUTION ORNL-1947 Progress 50. R. S. Livingston 51. R. N. Lyon 52. F. C. Maienschein 53. W. D. Manly 54. E. R. Mann 55. L. A, Mann 56. W. B. McDonald 57. F. W. McQuilkin 58. R. V. Meghreblian 59. A. J. Miller 60. K. Z. Morgan 61. E. J. Murphy 62. J. P. Murray (Y-12) 63. G. J. Nessle 64. R. B. Oliver 65. P. Patriarca 66. R. W. Peelle 67. A. M. Perry 68. W. G. Piper 69. H. F. Poppendiek 70. P. M. Reyling 71. H. W. Savage 72. A. W. Savolainen 73. R. B. Schultheiss 74. E. D. Shipley 75. A. Simon 76. 0. Sisman 77. G. P. Smith 78. A. H. Snell 79. C. D. Susano 80. J. A. Swartout 81. E. H. Taylor 82. D. B. Trauger 83. E. R. Van Artsdalen 84. F. C. Vonderlage 85. J. M. Warde 86. G. M. Watson 87. A. M. Weinberg 88. J. C. White 89. G. D. Whitman 90. E. P. Wigner {consultant) 91. G. C. Williams 92. J. C. Wilson C. E. Winters o e L X-10 Document Reference Library (Y-12) Laboratory Records Department Ft-ords, ORNL R.C. ) T TN L T T — -, - € o e e e g woTTETT T E b 128, 129. 130. 131 132 133, 134, 135-137. 138. 139. M40, B 141, - 142, 143-145. - 146. 147-149. 150. 151 152. 153. 154. 155.158. 159 - 160. 161. 162, 163. 164. 165. 166-167. 168. 169. 170. 171. 172. 173.. e '-‘-_174-176;__ - 177181 " EXTERNAL DISTRIBUTION AFDRD Jones AFDRQ AFSWC Aircraft Lab WADC (WCLS) Argonne National Laboratory yASSISfan Secretary — Air Force, R & b ATIC Afomlc Energy Commission, Washington BAGR - WADC Battelle Memorial Institute Boeing — Seattle BuAer — Mueller Chief of Naval Research Col. Gasser (WCST\) Convair - San Diego CVAC - Fort Worth Director of Laboratorles (WCL) Directorate of Weapons Systems, ARDC Douglas East Hartford Area Office Eciolpmént Ldbbi’qtory — WADC (WCLE) 'GE ~ ANPD Glenn L. Martin lowa State College KAPL Lockheed - Burbank Lockland Area Office Los Alamos Scientific Laboratory Maintenance Engineering Services Division — AMC (MCMTA) Materials Lab (WCRTO) Mound Laboratory NACA ~ Cleveland o NACA - Washmgton o North Amerlcan"'-/Aerophy5|C5 - RS Potem‘ Branch I‘lgton S '_Powe. Plant Laboratovry ~ WADC (WCLPU) Pra’rf &’:_Whl’rney (] copy to R. | Strough) - 182 R Sl ‘.“ifiDlwsmn of Reééarch and Medicme AEC ORO .o Ko e i, i Reports previously issued in this series are as foliows: ORNL-528 ORNL.-629 ORNL.-768 ORNL-858 ORNL-919 ~ ANP-60 ANP-65 ORNL-1154 ORNL-1170 ORNL-1227 ORNL-1294 ORNL-1375 ORNL-1439 ORNL-1515 ORNL-1556 ORNL- 1609 ORNL-1649 ORNL-1692 ORNL-1729 ORNL-1771 ORNL-1816 ORNL.- 1864 ORNL-1896 Period Ending November 30, 1949 Period Ending February 28, 1950 Period Ending May 31, 1950 Period Ending August 31, 1950 Period .En‘ding December 10, 1950 Period Ending March 10, 1951 Period Ending June 10, 1951 Period Endin)g September ]0', 1951 Period Ending December 10, 1951 Period Ending March 10, 1952 Period Ending June 10, 1952 Period Ending September 10, 1952 Period Ending December 10, 1952 Period Ending March 10, 1953 Period Ending June 10, 1953 Period Ending September ]0, 1953 Period Ending December 10, 1953 Period Ending March 10, 1954 Period Ending June 10, 1954 Period Ending September 10, 1954 Period Ending December 10, 1954 Period Ending March 10, 1955 Period Endifig June 10, 1955 € FOREWORD This quarterly progress ‘i'eport of the Aircrof'f Nuclear Propuisionr Project at ORNL records the technical progress of the research on Icirc_ulati'ng-.fue( reactors and all other ANP research at the Laboratory under its Contract W-7405-eng-26. The report is divided into three major parts: l. Reactor Theory, Component Develbbhént, and Construction, [l. Materials Research, and tH. Shielding Research. | The ANP Project is coifipfised of about 510 technical and scienfi,fi‘c personnel engaged in many phases of research directed toward fherqc‘rhrievemem‘ of nuclear pfopulsion of aircraft. A considerable portion of this research is performed in support of the work of other organizations participating in the national ANP effort. However, the bulk of the ANP research at ORNL is directed toward the de\felopmenf of a circulcfing-fuel type of react.or. The design, construction,i and operatibn of the Air'crdft Reactér Test (ART), with the coopera- tion of the Pratt & Whitney Aircraft Division, are the specific objectives of the project. The ART is to be a power plant sYs'remr that will include a 60-Mw circulating-fuel reflector-moderated reactor and adequfife means for heat disposal. Operation of the system will be for the purpose of determining the feasibility, and the problems associated with the design, construction, and “operation, of a high-power, circulating-fuel, reflector-moderated aircraft reactor system. - B iy e e i, b kil ., i FOREWORD CONTENTS ........................................................................................................................................................ SUMMARY ......oooovomenncnnn e | REACTOR THEORY, COMPONENT DEVELOPMENT, AND CONSTRUCTION PART 1. 1. REFLECTOR-MODERATED REACTOR ................................................................................................... .................................................................................................. Aircraft Reactor Test Facility Shielding Experiment Facility Aircraft Reactor Test Design .................................................................................................................... ...................................................................................................................... Reactor Design ........................................................................................................................................... Main and Auxiliary Radiator Design.. ..ot " Fuel-to-NaK Heat Exchanger Design ..., Core FIoW STUGI@S ..oiiiiiieiiie ettt et eb e et b et et e e e st a s st et e e re st e sae et e s Core Design ARGl Ses ....co.ooiiiiiii ettt e st er s e ee s e Fuel Pump Performance .........cooiiiieieiet ettt ettt et m e ebe et nes et s Controls and Instrumentation .................................................................................................................... Engineering Test UNit .ottt st st b sttt rseses Reactor Physics.............. OSSO UOO RSO SOPOORPOOY e ettt ses . Control Rod Heating and BUFIIUD ..ot ettt et as st s s st as s e s e s s et s s s s en e ART BOron Layer oottt ettt bbb a b bbb n e b s s High-Temperature Critical Experiment vs ART ..o Multigroup, Mulhreglon Reactor Caleulation ..o s 2. EXPERIMENTAL REACTOR ENGINEER!NG....7...........'... ..... e In-Pile Loop Development and Tests et ee ettt a e e et A oA R ae b A b bt a ettt ene s es e e b, L 00P IR STAIIAEION ... ottt ettt e Loop NO. T OPEIation ....ccoiuiriceerieieree ettt sttt et e e s s ettt s ene s e st eaeneeen. Horizontal-Shaft SUmp PuUmp ...t Ol TrradiGion ... Deve!opment and Operahon of F'orced Circulcmon Corros;on and Mass Trcnsfer Tests oo Operation of Fused Salt—Inconel Loops ..o st Liquid Metals in Mul’rlmetcl Loops..._ ..... e s s Pump Development .....iov....s/vooovveoeiioreeeee, et tbetatet et eeeb et ettt et b sbebereres e b eae e raatete e r e et Mechanical Shakedown and Be-armg and Secl Tesfs ..... bbb Short-Circuit Pump Test STANd oo, et eteteiesheitteeeaeat e e ntare et e aren e aree et erne e eteaneeee High- Temperature Pump Performcnce Test Stcmd ................................................................................ Heat Exchcnger Tests. . 7 7 Intermediate Heat Exchanger Tesfs e -'";"'”‘""t"'t ........ e e e Small Heat Exchqnger Tests ....... - ' ............................................................................. Str u;tqg’ql Tes’rs ........................................................................ 15 15 15 15 15 19 19 24 28 29 30 31 33 33 33 33 35 36 36 36 36 37 38 38 38 42 42 44 44 45 45 49 51 51 52 54 54 vii 3. CRITICAL EXPERIMENTS Room-Temperature Reflector-Moderated-Reactor Critical Experiments .........c.ccovorriiiinnrininnins S High-Temperature Reflector-Moderated-Reactor Critical Experiments......cccccoviiiinnnns e s PART 1. MATERIALS RESEARCH 4. CHEMISTRY OF REACTOR MATERIALS .ooooooeeoeee oo eeeseses s ess e o Phase Equilibrium Studies of Systems Containing ZrF ; and/or UF ; .cooooviiiniiiiiii, - The System LiF-ZrF .. oo s The System UF (-ZrF | oo The System NaF-LiF-ZrF ;.o The System NaF-LiF-UF (e The System NaF-RBF-ZrF ~UF ;oo s The System KF-ZrF ; oo e The System NaF~KF-ZrF4 ....................................................................................................................... Phase Equilibrium Studies of Systems Containing Bl s The System NaF-LiF-BeF , ..o The System NaF-LiF-BeF ,-UF ;.o The System NaF-BeF j-UF ;..o The System KF-BeF oo The System NaF-KF-BeF 5 ..o s Solubility of UF; in BeF,-Bearing Compositions ... Chemical Reactions in Molten Salts ..o s s Equilibrium Reduction of FeF, by H, in NaZrF o oo Reduction of UF ; by Structural Metals ..o Stability of Chromium and Iron Fluorides in Various Molten Fluorides .........c.ocooooivieviniiiin. Experimental Preparation of Pure FIuorides. ..ot Reaction of UF , with Uranium in Alkali Fluorides ... Reaction of Uranium Metal with Alkali Fluoride Mixtures .........ccccocoviviiieiiiiiee e Metal-Salt EqQUilTBrium oottt ettt et ettt en et et eaene Production of Purified FIluorides ...t e e s s Recovery of Contaminated Fuel for Re-Use.. ..o e Removal of CrF, from NaF-ZrF ,-UF , Mixtures ..o Effect of ZrO, in Fuel Preparation ... Pilot-Scale Purification Operations .........coceuvieioiiiicriveieiereesssseesessresssnsesieeesess s nesns e Production-Scale Operations ... et ettt ettt e Preparation of ZEF | ..ottt bt sttt esr b et ne st e paen Batching and Dispensing Operations ...ttt et asn e e s e seene Loading and Draining Operations ... Enriched Fuel Preparations ..ottt sttt ' Fundamental Chemistry of FUSed SAIES ..ot es s essees st eeeee e eeeseeee s Solubility of Xenon in Molten Salts ... e EME Measurements in FuUsed Salts .ot ee et eee et e st e e eee et eeeseeee et et es s eerasesesesnesseies Activity of Chromium in Inconel .......c.oooiiiiiiiiic s et . Viscosities of Molten NIrates ...ttt e Optical Properties and X-Ray Patterns for Recently Discovered k Compounds in Fluoride Systems ...t e s e High-Temperature X-Ray Spectrometer Studies .....cccvvivcininiiiiiiientncece e et nes i Physical Chemistry of Fused Salts ..o v 7 Diffraction Studies of Liquids.....cco.ooiuriioiiiicee oot e viii “ ¥} £ RGN i e+ R Ton S. F OrCed-CHrCUlaHON SHUGIES omvrooooeoseeeee e eseoee oot ee e oot es et Fluorides in Inconel ....... e e bR AL b e AR Sodium in Inconel and in Stainless Steel ..o Thermal-Convection Studies ... e - Effect of Yarious Loop Cleaning Methods.......ccocooccvvieiriesrierne. ettt sttt et e et est s s aeanan Effect of Heating Method .......oooi oottt et et - Effect of Temperatures............. e et ettt eeh ettt Ao e At bt et R ekttt e b ettt Effect of Applied Electromotive Forces .......coovoiiiiiiiciiiiii et ' Effecf of Oxide Additions 1o SOdiUm ...t General Corrosion SHUAIES ....o...eoooveeeereoeeeeeeeeeeseeeeese s e s eeeseesess st sess et e Hot-Pressed Metal-Bonded Tungsten Carbide in NaF- ZrF UF Solid-Phase Bonding OF COIMEES ..ccveeeeeeeeeee sttt e s et st es e s s Effects of Ruthenium on Physical Properties of Inconel ... ‘Brazing Alloys on Inconel and on Nickel in Sodium and in NaF-ZrF -UF .o, Brazing Alloys on Inconel and on Stainless Steel in Lithium ..o Hastelloy B=Inconel in NaF-ZrF -UF .ol et — et r e s ea et s st n e e n st s e en Boiling Sodium in Inconel ... et Inconel Exposed to a Sodium-Potassium-Lithium Mixture. ... - Molybdenum, Vanadium, and Niobium in Static Lithium ..o e Ana|y5|s of Metal Crystals from Inconel-Sodium Thermal Convecflon Loop .iovvveirinrieeii e, Fundamental Corrosion Research ... e et et eteeet e tetee et eee ettt tebe et st es e teates e te e anent st etesers s s Film Formation on Metals .........c.......... eeeeerteeraetastattesuiteesisie et ee st es s e bR bR A ba e b SRt e s bbbt ket High-Temperature Spectrophotometry in Fused Hydroxides .......c.coovoiioieiiniiiriinieieseienicieeeceecenes Mass Transfer and Corrosion in Fused Hydroxides ..., Thermol Dlssoc:qhon of Sodium Hydroxide................ ettt eeatehs et aebehe s b et et eht bt ettt et et et e b et eab s e ~ Chemical Studies of COEFOSTON e vereeee e eeereseeesseessseesessssseeseessesemeseessesesesssesoessseeeees s oeereee e " Inconel in NaF-LiF- ZrF4 U Stability of UF, in NaF-KF- L|F I INCONEI oo e Effect of Chromlum on the Mass Transfer of Nrckei in NaOH ............................................................ METALLURGY AND CERAMICS .................................. ". .......... ) ......... s s . Mechanical Property Tests of Inconel ................. e ettt reea—eit et et ot e tbeanseeaeae e s e e anseeteeas Stress-Rupture Tests e s ST OSSOSO OSSO POV OT U TERTUOPEPTPIOROPIOOY BEllOWS TSt irvooaersee oottt s est et aees st s ettt et Interaction Between inconel crnd Berylllum....;..;.Q.;.:....; ......... e et Development of Nickel Molybdenum A!loys ettt ettt ettt s et ' © OXidation SHUAIES .o e ettt Fabrlcatlon Studles...'_’./.;.‘._‘..'.'.'.'..;'..4...&." ...... e e s it . ~ Physical Properhes and M:crosfructure Sfud:es of Hastelloy B ' Brazmg of Boron Car_blde...:...f.'.',..f...'.'.:.'..'....:.'.... o Fabncohon of TestComponents "~ Components for High-Temperature Critical Experiment.........cooiiiiiiniinnaincnes s e ' Stress- Rupture Tesfs of Hasfelloy B CORROSION RESEARCH ..o ees oo oo eees oo e et er oo ere s ereee s oo Brazing Alloy Developmem‘ and Teshng Deveiopmenf Tests . Brozmg of Cermet Valve Seats fo‘ inconel Componem‘s o 7' o NcK-tg-Air Radiator 95 95 95 97 100 100 101 101 102 102 104 104 104 106 106 108 109 109 111 111 113 113 113 117 117 118 119 119 120 120 122 122 122 123 124 125 125 126 127 127 130 130 130 131 132 132 133 S ff'.:_:f.jfl-"'f "ANP Servnce Laborcfory 134 Intermediate Heat EXChanger NO. 3 ... eseeersee e eeeeee s s ereeesesesoeees s ee s er e es e ee s - Cornell Radiator No. 2 ... e s 135 o NondestrUCf-ive"Tesfing ................................................................................................................................ 136 1 Ceramtc RESEATCR et eeseee s eeereseeseesesee s eeeraessees s s emeseee e e et oo 140 * Graphite-Hydrogen Corrosion-Erosion INVESHGation ........coovcovvereevieeessersessesseseesssssssesseseeseseereme 140 Rare-Earth-Oxide Control Rods..........ccc.oiiiiiiiiieiin e s e ssse s 140 Calcium Fluoride and Aluming Detector SPacers ...........cococioiiininiiniininne e e 140 Fluoride Fuel Pellets. ..ottt ettt e 140 Synthesis of Boron Compounds .........coiiiviriiieiiriietcee ettt er bttt bt 140 Fabrication of Dysprosium Oxide Disks ...ttt 143 Fabrlcuhon of Europlum Oxtide Wafers......coooiiieceeee ettt 143 ik Specm| Materials Studies ....... SEURUROTPURRORRN ettt ettt e 144 R Cglfiumblym/Rexserqrch .................................................................................................................................. 144 Composite Tubing Fabrication ..ottt e e 145 Oxidation Tests of Aluminum Bronze.......ccccceeienuen, et eh et r ettt een et s et eas et s er e bt e ereeeete e e etae s eneos 146 C Lead-Calcium AHOYS ..o ettt 146 Neutron Shielding Material ..........ccooiiii et 147 HEAT TRANSFER AND PHYSICAL PROPERTIES .oooiovooveveroereeseeeeees oo e eooesno 149 Fused Salt Heat Transfer ... et nens 149 ART Fuel-to-Nak Heat Exchanger..........cccocoeveviinenn, ettt ettt r e 150 ART Core Hydrodynamics........o..oooioieioeeeteee oo eoe e . 151 Reactor Core Heat Tramsfer ... e 151 Heat Capacity ottt et e es e et enees 154 VESCOSITY oottt ettt ettt e e e et ee et 155 Thermal CondUCivity ..ottt eee et st ee e s er e 157 Electrical Conductivity oottt ee e e 157 RADIATION DAMAGE ...ttt e 158 LITR Horizontal-Beam-Hole Fluoride-Fuel Loop ......iocoioiiiieieieeeieeeeeeeteeeeeeeeee e 158 Miniature TR-Pile Loop oottt ee e er et es et 164 Creep and Stress-Corrosion T@StS. ..ottt eee et eer e ee e e res st s e es e ee s es s 165 Flux Measurements in the MTR .. oo e, 166 Analysis of Reactor-Grade Beryllium ..o 169 ANALYTICAL CHEMISTRY OF REACTOR MATERIALS oo, - 172 Determination of Oxygen in Sodium........co.co..iviiiiioceieee e ees e 172 7-Butyl Bromide Method ........ccoooiiiiiiiiii et e ee e 172 Vacuum-Distillation Method................... OO UOU PO O SOOI 173 Volumetric Determination of Zirconium in Fluoride Salts with , _ Disodium Dihydrogen Ethylenediaminetetraacetate (EDTA) e, 173 Determlnatlon of Uranium Metal in Fluoride Salt M:xtures et b ettt n e, 175 Ehmmahon of Air from @ Dry Box.........cooiiiiiii s | 175 o 'Defermlnatlon of Oxygen in Metallic Oxides by Bromination ..o, — 175 Lt Determmahon of CO by Means of a Solution of PACl, o 176 177 hn:x;!;_ 10. RECOVERY AND REPROCESSING OF REACTOR FUEL ...coooovviiiiiierce i 179 Pilot Plant Design.. oo ooveeieee e et s e s s 179 Engineering Developments ...........c.cocoiiiiiiiiiiie ettt 179 Process DevelOPmMENnt ..........cccoivivoieee oottt ek 180 o PART Ill. SHIELDING RESEARCH 11. SHIELD DESIGN st SRR - - Welghts of Spherlcolly Symmetric Unit Shields for C:rculahng-Fuel Reactors.......cceeeeevieeeivceennnennnn, 185 Sources of Radiation in a 300 Mw Circulating-Fuel Reactor ... 185 ~ Shield Weight Dependence on the Dimensions of a 300-Mw Clrcula’rlng-FueI Reactor ....cccocvveeunnn. 189 - Neutron Shield ... ettt eeateteettteteoatteteertaeearse e e ehe et s et b e e et e et eet e et e e et te et e san e 190 Gamma-Ray Shield ... 191 We|ght D et e MINGEIONS o oottt ettt ettt s e rs e e et e en e e et e et e et e ent e e aan e eeenbeeneas 195 12. LID TANK SHIELDING FACILITY oo oo .97 Reflector-Moderated-Reactor and Shield _Mockup TSt S oottt e e 197 Gamma-Ray and Neutron Measurements Beyond the Mockups.....oooociiie, 197 ~ Sodium Activation in the Heat Exchanger Region of the MockUpS oo 197 13. BULK SH!ELDING FACILITY s 199 _Angular Distribution of Fast Neutrons Through Water oo e e 199 | Decay of Flssmn-Produc’r Gamma Radmflon ............................................................................................ 201 14. TOWER SHIELDING FACiL[TY ................................................................................................................ 205 ' Procedurerfor Using TSF Data for the Optimization of a Divided Neutron Shield.........coooeiee. 205 - Calculation of Shield Weight ....................... OSSOSO PO OO OO TS POT SO UORR OO 205 CalcuUlation of DoSe Rat ....c.ooioviioeiieieie oottt bttt 206 Calculation of Minimum Shield Weight for Specified DoSe .o, 208 Appl:caflon OF TSF DIGHG ..ot 211 - Results of a Sample Shield Opflmizution Calculation ..o s 215 Measuremenfs in fhe GE ANP Crew Compcrtmenf Mockup e I e 217 ORGAN!ZATION CHARTS e 221 xi T IR 1 Cewl ""ro gef q high degree of mIXIng T orie’ system “the vortex axes paro”el ‘the |s!and ‘and ANP PROJECT QUARTERLY PROGRESS REPORT SUMMARY 'PART I. REACTOR THEORY, COMPONENT DEVELOPMENT, AND CONSTRUCTION - 17. Reflector-Moderoted Reactor - A confract was oworded on Augusi 19 ]955 to the V. L. Nicholson Cornpany, ‘Knoxville, Tennessee, _'rhe Iow bldder for pockoge ] of the Aircraft Reactor ‘Test (ART) focdrfy. Therr low ‘b:d of $765,835 included $264,373 for the reactor cell, with the Chrcogo Bridge & lron Co. engaged to serve as “the subcom‘ractor to des:gn, fabricate, and erect the cell, Package 1 includes, in addition to the “cell, the major modifications of Building 7503. Recent experiments at the Tower Shielding Focr]rfy (TSF) emphasized the need for shleldlng data from the ART, and therefore a layout has been comple‘red to provrde for the measurement of the gommo-roy ‘spectrum of the ART as a function of the angle of emission from the reacfor shleld ; surfoce. - Layout drow:ngs have been completed for the prmcrpol features of the ART reactor—pump-—heat exchanger-—-pressure shell assembly, and the de- tails are considered to be sufflcrenfly firm for procurement to be started. Fabrication of the 4‘she'Hs, such as the pressure shell, reflecfor | shell, etc., will be particularly hme-consumlng because of die problems, and fherefore procurement ' ’work began with the shells, A one-bclf-scole plcshc model of fhe pump ‘and expansion tank reg'°“ at the *OP of the reactor hos been completed to facilitate exommcmon of fob - cation, stress, and flmd-flow problems, ond wo k has started on a‘full scale olummum'model sign condmons a e stab for the main and auxiliary radlorors,fand rhe de- sign for the fuel-to-NaK heat ‘exchanger has been selected Design colculotlons ond loyout drowungs N IR L mveshgoted bofh mqke us in the other they spiral helically downward around it. In both systems the two fuel pump volutes dis- _date Mfor ini The ob|ec’r|ves of 'fhe ETU ore to devefop fechmques_ chorge 'rongenholly into the core to give a system that is insensitive to the one-pump-out condition, Tests performed to date were planned to assist in the systematic development of an inlet-guide-vane and turbulence-generator design that will produce radial velocities of sufficient magnitude to keep the boundary-layer fluid mixed with the free stream. High-speed photographs of dye injections and con- ductivity measurements of salt injections are being used fo examine radial flow, circumferential dis- tribution, and transients, Core designs with lower degrees of divergence than that of the present 21-in. design are being studied to determine the effect of inlet annulus dimensions on the adverse pressure gradients encountered by the fuel in flowing from the core inlet to the equator. Performance tests of the fuel pump with water as the circulated fluid were completed. The noise present in the initial testing was found to result from a local flow condition that existed at the tongue of the pump volute. A modification of the volute design has eliminated the noise, and other impeller modifications have brought about a con- dition in which the hydraulic force balance on the impeller occurs near design speed and flow., The tests have demonstrated that the design point lies in the region of maximum efficiency. A flow sheet has been prepared that shows, schematically, the locations of the principal instrumentation ond com‘rol components of the ART _ond control pcmel loyout studies are being ,_mcde. Excepf for special sensmg eqmpmem‘, it appears fhat no development ‘work will be requrred LA construchon program fo_r the Engmeermg Test (.ETU) hqs been esfoblushed with a _target [ operohon f September 1, 1956. e e B S T b]y, fo obtain some on the -rodlotors ond the NaK 'ro fuel ond fhe sodlum~ urfs, cmd to fest some of the mstrumen- be used_ 'on ‘the ART o Calculations 'ofwcontrol rod heatmg and burnup to " be expected in the ART were completed, and the relative merits of various materials were studied, For example, for a 1/‘!-in. annular control rod of T B TR B W I " ANP PROJECT PROGRESS REPORT ¥ : BIOC in arcep'per matrix (30 vol % B 4C) thébdrhub“ = penetrahon would be one-sixth as great as that in a europ:um oxide cermet, but the heat produced would be one-third greater. The boron layer be- 'f:_'rween ’rhe reflector and the fuel-to-NaK' heat ex- _ changer was exammed with respect to heat genera- ':”.':tlon, flux afienuahon, helium gas evoluhon, and burnup. Also, the differences between the ART and the “hi'grh ‘ferfi'perdtdre critical experiment were . ‘evaluated. It is estimated that the critical con- | . j'_'f'cenfrahon of the ART WI“ be between 4 6 and 5.4 “,'Ti_'mole % UF ' compufe fluxes as a funchon of one space variable in slcb cyhndflccl or spherical geometry, and it 'wull allow 125 groups and 125 regnons. 2 Experlmental Reucfor Engineering The frrsf loop for” c:rcu!cmng fluoride fuel inb hole HB-3 of the MTR was shipped to NRTS on June 20. It successfully passed the preoperational checks, and startup of the loop proceeded satis- factorily to the final step, that is, melting of the freeze line and filling of the loop with the fuel mixture. The heater for the freeze line was found to be inoperable, and therefore the experiment was terminated. The loop has been returned to ORNL and disassembled, The modifications required to overcome the difficulties encountered have been incorporated in a second loop that is nearly ready for shipment to NRTS, A third loop is also being fabricated. The auxiliary facilities required ot the MTR for operation of the in-pile loop were com- pleted, including a loop retractor mechanism for adjustment of the loop nose position during reactor operation. Twenty-two fused-salt—Inconel forced-circulation | loops were operafed in the test program for studying corrosion and mass-transfer in high-temperature- differential, htgh velocity systems under conditions that simulate reactor flow rates and temperatures. Nine similar loops were operated with sodium in Inconel or in srcnnless sfee! tubmg. A new test loop has been des:gned w:th whlch it will be possnbie to obtain accurate information ~ ... on 'rhe oxygen content of sodium or NaK during pera’r:on of the loop. The main loop of the system is to include a bypass cold trap and a sampling en.d analyzing device, and cnauxfl:arypluggmg- indicator loop will be attached to the main loop. Also, a loop has been designed, in which NaK will be circulated, that has the same ratio of surface area to volume as that of the primary NcK cnrcuufs of the ART, The design layouts for two loops for high- temperature tests of full-scale models of the ART fuel and sodium pumps were completed, and fabri- cation and assembly were started, The first group of bearing-and-seal and mechanical tests on the rotary elements of the pumps was completed. In A new muihgroup,mulhreglon reactor caleulation general, the test results indicate that the bearing- Cis bemg programed for the Oracle. The code will and-seal designs for the upper and lower units can ‘be made to function satisfactorily. One short- circuit pump-test stand was completed and shake- down tests with water were started. Intermediate heat exchanger test stand A was 'operc:'red for 690 hr in a series of furnace and"‘_: diffusion cold-trap tests of the NaK circuit and a 2-hr cleaning cycle of the fluoride-fuel circuit. The gas-fired furnace for heating the NaK proved to be copable of transferring 1.13 Mev of heat to the NaK aofter minor modifications, including in- stallation of a larger burner, had been made, After the fuel mixture had been circulated and dumped, a leak occurred in one tube bundle of the heat exchanger, and subsequently one of the NaK-to-air radiators developed a leak. The leak in the heat exchanger was found to be a radial crack on the inside of a tube bend, It was dlso found that severe distortion had occurred as a result of the thermal cycling created by operating the heat exchanger with NaK in the tubes but with- out fuel around the tubes. The temperature dif- ferences thus created ranged from 200 to 1000°F The failure of the radiator is also thought to be the result of extreme thermal cyclmg, but the analyses of the difficulties have not yet been completed. ‘Additional test assemblies are being fabricated. The first series of tests were completed on a small (20-tube bundle) heat exchanger that was operated nearly continuously for 1560 hr. Heat transfer, pressure drop, and corrosion and mass- transfer data were obtained. No appreciable amount of mass fransfer could be detected by visual inspection, and metallurgical examination is under way. The oxide content of the NaK' was found to be high, and therefore cold 'rrcps ore ‘ro be lnstolled in subsequent test !oops. i .;tl;":‘ I - A . -, 4 "cenhmeter of fuel region, and a -\ one-fourfh-scale model of the lower half of the 21-in. reactor core shell was fobrlccted for thermal- ‘stability tests, and a design was completed of an Inconel strain-cycling rig. A third thermal-cycling test of a sodium-béfyl!iquEnconel system was 'sfarted A systemcmc study was made of devices " for the measurement of oxides in circulating sodium or NaK and the removal of the oxides during operahon. Designs of cold traps and plug ) mdlcators were prepared ' ' 3 Crmcal Expenmenfs c The fuel concentrcmon in the room-iempera’rure' ’ crmcal assembiy of the reflector-moderated circu- latmg-fuel reactor was decreased from 0.416 (3% excess react:vnfy) to 0345 g of y23s per cubic “‘clean’’ critical mass of 19.9 kg of U235 was obtained. Two s'rrucfurol chqnges in the assembly were also studied. ln one of the modlflcchcms, the average TWIdfh of one of the end ducts was mcreased from '(29 to 2 80 m., which increased its volume al- 'most 2.5 hmes. The corresponding critical mass ‘was’ about 24 kg of U235. In the other alteration, the radius at the center of the berylllum island was increased from 5.18 to 7.19 in. The critical mass of th:s assembly was 18 4 kg of U235 Another crmcal assembly of this reactor is bemg‘ | opercfed at fempercfures between 1200 and 1350°F, The mmlmum cnhcal concenfrcn‘lcm has been de- termmed as 6.29 wt % (2 96 mole % urcmlum ina mixture of sodium, zrrconlum, and enriched uranium '; __fluor:des. The Over-aH temperature coefficient of redctivity is -2 >< ]0-5 (Ak/k)/oF and the control . h : ifielfmg pomfs were accompamed\:by exceechngly‘a':"T " high vcpor pressures of ZrF ;. In the NaF-LiF-UF system ‘it was found that mixtures in the reglons PERIOD ENDING SEPTEMBER 10, 1955 of low meltlng pom’r contained too much UF, for use with circulating-fuel reactors, Preliminary studies were made of the NaF-RbF- ZrF ,-UF, system fo determine whether it could provide a low-viscosity fuel. Previous work on the RbF-ZrF, system had demonstrated the need for a fourth component in order to obtdin a low-melting fuel with 20 to 40 mole % ZrF4. All the work was carried out with RbF which contained about 20 mole % KF as an impurity. The KF caused un- expected results in the phase diagram work, which has therefore been postponed until better RbF can be procured Viscosity measurements in the sys- tem RbF-ZrF -UF (48-48-4 mole %) below 600°C were hmdered by particulate matter, but the measurements made above 600°C gave viscosity values which were somewhat lower than those in the NaF-ZrF -UF, system. In order to obtain further msrght into ’rhe mixtures containing rubidium, sfudles were made in the KF- -ZrF , and NaF-KF- ZrF4 systems, The latter system proved fo be much more complex than either the NaF-ZrF ,-UF or NaF-LiF-UF, systems, which show no 'rerncry compounds. The NaF-KF-ZrF, system was shown to have at least five ternary compounds. In the system NaF-LlF-BeF2 it was found that acceptably low melting points can be obtained with low LiF concentration by moving into the ternary system along the drainage path leading from the NaF-Na,BeF, eutectic toward the LiF-Na,BeF, eutectic. In order to obtain-a melt with a kinematic viscosity as low as that of the ARE-type fuel, it was established that the BeF, content cannot be greater than 30 mole % to assure complexing of BeF as BeF ™" The LiF content will probably have 1o _be. less than 10 mole %. The melting “point of NaF LIF Ber (63.5-7.5-29" mole %) was found to be 4A525°C -and a defermma’non of its mixtul es the concen- ot 800°C is about il i trotioh"of Urcimum (in g/cm the same as the concentration of NaF-ZrF4-UF4 (50-46-4 mole %). '____f’uture. ) The_ | P T o TR L g driiac, o peah R 'ANP PROJECT PROGRESS REPORT “io 0 Liquidus temperatures were determined for mix- " tures of NaF-BeF, (70-30 mole %) with about 2.5 ‘mole % UF4 because of the reported low viscosity : *’_flig_of the NaF- BeF2 mixture., The liquidus tempera- fures were in the _region of 560°C, which is un- 3 Jf’sahsfactorlly high. A more complete investigation < of melting points in the NaF-KF- BeF system "ff'}_f{f;:,-conf:rmed prevrous observahons of hrgh hqurdus ~ temperatures. ’ Analyses were carried out on mixtures of UF3 -U ,ikf-and UF -U dissolved in LrF—BeF and NaF-BeF :-;»‘.‘,me]fs cmd filtered in either copper or nickel equ:p- 5 _;'_imenf. The results showed that the solublhty and | ;“}srcblhty of UF in these melts were not solely a _‘func'rlon of the form of the uranium addition and the confomer mefcl The resulfs were errahc, ‘and ‘_further experlmentoflon |s necessary To defermrne the controihng foctors. By means of an equrllbrcmon technique pre- - .viously described, a more precise value for the “equilibrium constant of the reaction FeF2 + H,=— Fe® + 2HF in NaZrF, was found to be K 5 2 at a concentration of FeF2 corresponding to 6490 ppm of iron. A study was made of the re- duction of UF , in NaF-LiF-UF, (22-55-23 mole %) by Cr® and Fe® at 600 and 800°C. The equilibrium 210, Iy 4(@9) || NaF-ZrF, () M| MF NaF ZrF 2(satd)’ (a )' i chromium concentrations were found to be lower than those of fuels with greater-concentrations of ZrF,. The equilibrium iron value remained about the same as that of fuels made with NaF-ZrF, mixtures and the NaF-LiF- KF eutectic, but lts temperature coefficient was reversed to give slightly higher values ot 800°C than at 600°C, Data were obtained on the stability of iron fluorides cnd chromlum fluorides in various fused matena!s. Reducflons of UF4 wr'rh excess uranium were carried out in several melts. In the NaF-LiF eutectic the UF, was more stable in copper than in n:ckel equipment, In the NaF-KF-LiF eu- tectic the stability of UF, was ‘independent of the container, and, with copper containers, a uranium- copper alloy was found. This alloying 7_wnrh copper did not occur with either NaF-LiF "/euiechc or BeF, melts, A sfudy of the reaction of metallic uranium with ""_'_several fused mm‘erlcls at elevated temperctures dlsclosed reduchon and volaflhzohon of olkah' metals. Equilibrium studies on mixtures of potassium metal and NaF gave results that led to an equilibrium constant at 800°C of o K= (Na/K)KF/NaF) = 0.2 . Workable methods have been devised for re- processing fuel used in component testing at ORNL and Pratt & Whitney. It is expected that 2000 to 3000 Ib will scon be available each month for reprocessing and re-use. Since a satisfactory commercial source of ZrF , has not yet been found, a unit is being fabricated which is capable of pro- ‘ducing 1000 Ib of ZrF, per week by direct low- temperature hydrofluorination of ZrCi ,. A shortage of ZrF, reduced operation of the large-scale (250-1b bcn‘ch) fluoride-processing facil- ity to one-half the normal capacity during this quarter. A total of 6960 Ib of purified fluoride compositions was produced, including the fuel carrier for the ART high-temperature critical ex- periment, Pilot-scale equipment was used to pro- duce 53 batches of purified fluorides. Enriched fuels were prepared for the high-temperature critical and in-pile loop experiments. Examinations have been made of cells of fhe type 1 1 NaF ZrF4(a;), M Fz(sq*d) M, where M and M! are Cre, Fe°,'crnd Ni®, These cells appear to be reversible and are reproducible. Interpretation of the data is complicated by the solid fluorides in equilibrium with the melt not being simple metal fluorides and their compositions being dependent on the amount of fluoride present in excess of the saturation value, Reproducible emf’s have also been obtained in the case where M and M! are Cr° and where fhe (':.rF2 content is " less than the saturation value at one of the elec- trodes. In the cell Cr|NaF, ZrF,, CrF, | Inconel, with no barrier between the Inconel and chromium, the potential eventually dropped to zero because of the Inconel being converted effecflvely to a chromium electrode. The mechanism for tronsportr of chromium might include dlsproporhonahon of CrF, to CrF, and Cr® at each electrode, with the solution being carried from one electrode to the other by means of convection currents, Ophcal properhes and x-rcxy patferns were de- . el e o T T termined for several newly encountered compounds in the fluoride systems. High-temperature x-ray diffraction was used to study the polymorphs of Li,ZrF,. Progress is reported in the efforts to obtain high-temperature x-ray and neutron-diffraction data on fused materials to serve as an aid in de’rermmmg the molecular structure of the melts. A summary is presented of the work on the electrical conductance, density, and freezing-point depression measure- ments with various alkali and heavy metal halides. Self-diffusion coefficients are reported for sodium and nitrate ion in fused sodium nitrate. 5. Corrosion Research Examinations were made of several Inconel forced-circulation loops operated with NaF-ZrF - UF, (50-46-4 mole %) as the circulated fluid for various times under otherwise identical conditions. These loops, which were direct-resistance heated, had o temperature differential of 200°F, a Reynolds number of 10,000, a maximum fluid temperature of 1500°F, and a maximum wall temperature of 1600 to 1625°F. A curve obtained by plotting depth of attack vs operating time exhibited the two-stage type of attack found previously in thermal-convection loops; that is, the initial rapid attack that occurred while chemical equilibrium was being established and the impurities were reacting was followed by the slower mass-transfer type of attack. An at- tack rate of 3 to 4 mils per 1000 hr was found for the second stage of attack. In two similar loops operated under the same conditions, except that one was heated in a gas furnace and the other was heated by electrical resistance of the tubing, the depth of attack was not found to be affected by the heating method, Another similar loop with a maxi- mum wall temperature approximately 100°F higher fluoride mixture temperature. Additional data have been accumuluted on mcss::': “force ’irculatlon syss ‘ ‘perature “dif- ferential and mass fransfer "was‘hfound but “in- creqsmg ‘the oxnde contenf “of the “sodium did transfer in sodwm-lncone! f ced— tems. No correlcn‘lon befw ' increase the mass transfer. In an all-stainless- steel loop in which sodium was circulated, there was a mass-transferred layer that was 0.8 mil PERIOD ENDING SEPTEMBER 10, 1955 thick, in contrast to a 9-mil-thick layer found in an Inconel loop with a stainless steel cold leg. In an effort to ascertain the cause of the erratic results being obtained with Inconel thermal- convection loops, several loops were cleaned by different methods and then operated with NaF- ZtF -UF, as the circulated fluid. No effects attributable to the cleaning method could be found. In other tests, heat was applied by direct electrical resistance of the wall rather than by the usual “‘clamshell”’ electric heaters, The resulis confirmed a previous conclusion that the depth of attack was not affected by the method of heating. Since the forced-circulation loops had indicated that the maximum loop wall temperature was a significant variable, thermocouples were installed on the hot legs of two standard lnconel thermal- convection loops to study this effect. Preliminary results indicate that the wall temperatures may have been as much as 1670°F, in contrast to wall temperatures of about 1600°F in the forced-circu- lation loops. The higher temperature difference between the wall and the fluid may account for the attack in the thermal-convection loops being deeper than in the forced-circulation loops. A series of thermal-convection loops have also been operated with small applied potentials., The loop which circulated NaF-ZrF ,-UF, for 2000 hr with a positive charge applied to the hot leg showed only dbout one-half the depth of attack found in the loop operated with a negative charge applied to the hot leg. With a negative hot leg the attack was about the same as that with no applied po- tential. Inconel thermal-convection loops operated with sodium gave results which confirmed those obtained with forced-circulation loops. Hot-pressed metal-bonded tungsten carbide ~ cermets were fested in NaF-ZrF -UF, and in than the usual 1600 to 1625°F showed heavy sub- surface-void attack to a depth of 18 mils. Thus additional evidence was obtained that the wall temperature is a more crmcol varmble fhan 15 the'_" - sodium in seesaw apparatus; no measurable attack was found on any specimens, Similar additional tests were made of the Kentanium cermets. The __best of the Kentcmlum cermets are being fabricated into valve dlsks and seats for self-bonding tests under service condmons. Ruthenium was plated onto Inconel for tests of " creep-rupture properties of the plated specimen. 'Prehmmary results indicate an increase in creep rate and a decrecse in rupture life, m comparlson ‘with standard Inconel. Additional screening tests were made of Inconel T-joints brazed with various dlloys and exposed to fluoride mixtures and to v R W TS T T ANP PROJECT PROGRESS REPORT - sodium, and several brazing alloys on Inconel and ~ on stainless steel were tested in static lithium. Al ‘the brczmg alloys tested showed poor corrosion * resistance to lithium. A static test of a Hastelloy B specimen in an Inconel capsule containing a fluoride mixture showed the Hastelloy B to be unattacked, but the Inconel was attacked fo a depth of 8 mils, in con- trast to a normal attack to a depth of 2 mils in a static Inconel ccpsule without the Hcsfel]oy B specimen, Experiments are under way with a boiling-sodium— * Inconel system so that the effect of oxide-free - sodium on mass transfer can be studied. In pre- liminary experiments no mass transfer could be ~ detected. Seesaw corrosion tests have been made on Inconel capsules loaded with sodium-potassium- lithium mixtures in which the lithium content was varied from 2 to 30 wt %. The heaviest attack was found in the hot section of each tube, and it varied from 0.5 mil in the presence of 10% lithium to 2 to 3 mils in the presence of 5% lithium. Molybdenum, vanadium, and niobium were tested in static lithium at 1500°F, Molybdenum was unattacked, niobium was only slightly attacked, and vanadium showed grain-boundary penetration by an uniden- tified phase to o depth of 2 mils. Measurements of the oxidation rate of metallic sodium at 25 and 48°C were extended to periods of 2 x 10% min, The data obtained do not fit any of the postulated oxidation-rate theories, although highly protective oxide films were formed. Measurements of the oxidation rate of metallic columbium confirmed the previously reported change in rate law with time. Tentative conclusions have been drawn . ‘concerning the origin of the change. Improvements in technique have been made for e studymg fused sodium hydroxide by spectrophoto- - metric techmques. Measurements of corrosion in fused sodlum hydroxlde have shown that water ~'vapor is an important inhibitor and that the pres- ence or absence of a closed electrical circuit be- V’rween the hot ‘and cold parts of the corroding ~ system has a significant effect on mass transfer. © Measurements of the self-dissociation of sodium hydroxude have been made for the first time in the "~ absence of s:de reactions. Both the expected decomposmon into water and sodium oxide and the postulated decomposition to produce hydrogen have been confirmed, A series of studies of thefour-componentfuel NaF-LiF- ZrF4 -UF , (22-37.5-35.2-5mole %) exposed for 100 hr in sealed ccpsules of Inconel in the standard rocking furnace have indicated that this mixture may be less corrosive than others being considered, A series of mixtures of the NaF-KF- LiF eutectic with UF; and UF, added were also tested in Inconel in the rocking-furnace apparatus. The data indicate that UF, is quite unstable under these conditions, regardless of the original UF,- to-UF, ratio. It also appears that considerable disproportionation of UF ; must be expected in this sy stem. ' ' In experiments for determining the effect of chromium on the mass transfer of nickel in NaOH, it was not obvious that the chromium was particu- larly beneficial. However, it was shown that some mechanism for preventing the loss of hydrogen from the system ~ perhaps cladding the nickel with some metal impervious to hydrogen - might be quite berieficial. : 6. Metallurgy and Ceramics Mechanical property investigations of Inconel have continued with stress-rupture tests of Z-in. tubing in argon and in fused salts at 1300, 1500, and 1650°F. A comparison of creep-rupture dnd tube-burst data showed similar rupture times for 0.060-in.-wall tubing and 0.060-in.-thick sheet in argon and in NaF-ZrF -UF, (50-46-4 mole %) at 1500°F. The data being obtained indicate that the presence of an axial stress in the tubing does not appreciably affect the time to failure., Data obtained for tubing with 0.010-, 0.020-, and 0.040-in. walls show, in comparison with data for 0.060-in.-wall tubing, that the thinner the wall the shorter the rupture life at comparable stresses. An evaluation test in fused-salt fuel of an Inconel bellows with a welded diaphragm showed only normal corrosion attack in the weld areas and no cracks that resulted from flexmg of the bellows. A determination of the extent of inter- action between beryllium and Inconel in contaci at high temperatures in an inert environment was made. The results indicated that an intermetdllic layer was formed that would be detrimental to the load-carrying capacity of the Inconel. This in- formation was needed in the design of the high- temperature critical experiment, : Additional tests were made of nickel-molybdenum alloys containing titanium, aluminum, vanadium, zirconium, columbium, or chromium which con- firmed the previously reported embrittlement of these ternary alloys after a long heat treatment at elevated temperatures in hydrogen. The ductility of the alloy can be restored by a high-temperature anneal in vacuum. In the study of factors affect- ing the fabricability of Hastelloy B, it was found that canning the extrusion billets with Inconel teduced the pressure required during the extrusion and at the some time clad the alloy tubing with a heat-resistant alloy. A series of creep-rupture tests of solution- annealed, 0.060-in.-thick, Hastelloy B sheet at 1500 and 1650°F in NaF- ZrF ,-UF ; (50-46-4 mole %) were completed and de5|gn curves were pre- pared. The influence of aging heat treatments on the creep-rupture properties of Hastelloy B is being studied in the range 1300 to 1800°F in argon. The creep-rupture properties at 1800°F ‘are not substantially affected by aging, since at this temperature a single-phase alloy exists. How- ever, at 1500°F a second phase appears to exist in aged specimens which increases the rupture life at high stresses. Short-time tensile tests ' conducted after long-time aging of cold-worked Hastelloy B at high temperatures indicate that ‘tesidual stresses from the cold-working operation ‘are quite detrimental to ductility. Data showed the ductilities of cold-worked specimens to be considerably lower than those of specimens an- nealed before aging. Microstructural studies indi- ¢ate that cold work induces precipitation in larger quantities and perhaps in smaller particles than does annealing. ‘Additional oxudanon-resns’rance tests of high- temperature brazmg alloys were ‘conducted, and melting-point studies are being made by using sintered, conical samples. Experiments are under way in an attempt to find an alloy for brazing a boroh carbide compact to an Inconel envelope. The alloys lnveshga’red thus far that wet the boron carbide also react with it to form brittle bonds that crack upon coohng. The boron carbide— Inconel assembly is requu'ed for rodlqhon shield- ing in fused-salt pumps. A'success ful method ‘was es’rabhshed for brqzmg Kenmmum cermet vc]ve" seats to lnconel sfrucfural components. Nnckel |s' N from the different coeffimenfs of thermal expcnsxon of Inconel and the cermet, The lnconel core-shell assembly for the high- PERIOD ENDING SEPTEMBER 10, 1955 temperature ‘critical experiment was fabricated after the development of experimental techniques for minimizing distortion. The fabrication of a third, 500-kw, NaK-to-air radiator is under way, The design of the radiator is essentially the same as that used previously, but improved fabrication techniques are being utilized, Presintered rings are to be used for the preplacement of brazing alloy. One tube bundle of the fuel-to-NaK inter- mediate heat exchanger No. 3 has been completed, and construction of the second tube bundle is under way. Design modifications for this heat exchanger have included the use of larger diameter fubing (0.250 in.) and the elimination of right-angle corners of header components to provide better stress distribution. A second liquid-metal-to-air radiator was fabricated for the Cornell Aeroncuflcal L aboratory, An eddy-current method for flaw detection in [ow-conductivity tubing is being investigated. Studies have shown that an ultrasonic method for the inspection of small-diameter tubing is suf- ficiently sensitive to detect the types of flaws encountered to date. Corrosion-erosion in graphite-hydrogen systems at 2400°C, with a hydrogen velocity of Mach 0.15, is being investigated., Present indications are that the slight weight losses observed were due to the small amounts of water vapor in the gas. Two rare-earth-oxide control rod assemblies were prepared for critical experiments; flux-detector spacers of calcium fluoride and alumina were pro- duced; dysprosium oxide disks were prepared for use in measuring thermal flux; and a method for preparing europium oxide wafers was investigated, A study of the feasibility of synthesizing MozBs and B,C was started, and the optimum pressing conditions for pelletizing fluoride fuels are being determined. Investigations of diffusion barriers for use be- tween Inconel and columbium have shown only tantalum and copper to be useful. Tests for de- termining 'rhe more saflsfoctory of the two barrier materials are under way. Mixtures of columbium and UO,, being considered for use as fuel elements “were tested at 1500 and 1832°F for 100 hr. A solid solution of Cb-U and a pinkish phase, as yet Jumdenhfned formed in the samples. The deformation patterns obtained in two- and three-ply extrusions of metal tubing were studied, and limits were established on the metal ratios 1 ANP PROJECT PROGRESS REPORT and on the configurations of the billets that can be successfully extruded, The creep performance of " lead-calcium was found to depend upon the care with which the master alloys were made. This implies that an accurate knowledge of the amount “of alloyed calcium rather than total calcium is required. Therefore, chemical analyses, which give a measure of the total calcium, were found to be an unreliable index for predicting the creep properties of the alloy. The fabrication of boron-containing materials for use as neutron shielding is being studied. At present, attempts are being made to thermally bond boron-containing layers to Inconel, The use of B;C tiles is also being considered for locations where therma[ bonds are not necessary, 7. Heut Trunsfer and Phys:cul Properties Forced-convectlon hec'r transfer medasurements were made for ‘molten NaF-KF-LiF- UF, (11.2-41- 45,3-2.5 mole %) which was flowing furbulem‘ly through type 316 stainless steel tubes. The re- sults were comparable with those obtained pre- viously in an Inconel tube and were thus 40% below the general turbulent-flow heat transfer correlation, A check on the experimental apparatus was ob- tained by operating it with water as the heat trans- fer medium, and the data were in good agreement with the general turbulent-flow correlation, The low heat transfer valuves obtained with NaF-KF- LiF-UF, therefore appear to be real. The heat transfer and friction characteristics of a full-scale model of the ART heat exchanger were determined with and without the presence of tube spacers. These results were compared with conventional heat transfer and friction relations for simple duct systems. As was to be expected, both the heat transfer coefficients and the friction factors decreased upon removal of the tube spacers, However,' when the spacers were removed, the | tubes were not held rigadly and channeling occurred in the flow pch‘ern. A summcry of hydrodynamic research on models .of the 18- and 2l-in. ART cores has been pre- pared. Rotational and axial flow patterns, as ‘well as various entrance conditions, were studied, One core, which had a low ratio of flow cross- sectional area at the equator to flow cross-sectional “area at the inlet, was characterized by uniform and steady flow. ~ The temperature distributions within fluids flow- ing through converging and diverging channels were .experimenfcny determined in the volume-heat- source system, Information on the transient be- havior of the wall temperatures, as well as on the asymmetry of wall temperature profiles, was ob- tained for these uncooled channels. A report has been prepared which describes applications to general convection problems of previously de- veloped mathematical temperature solutions for forced-convection systems having volume heat sources within the fluids. The enthalpies and heat capacities of LiF-KF {50-50 mole %) were determined in the liquid and solid states, The viscosities of eight fluoride mixtures were determined. A mixture of RbF and LiF (57-43 mole %) yielded a viscosity of 9.0 centipoises at 500°C and 3.4 centipoises at 650°C, An RbF counterpart of the ART fuel was formu- lated, This mixture, whose composition is RbF- ZtF ,-UF, (48-48-4 mole %), had a viscosity of 9.5 centipoises at 550°C and 3.1 centipoises at 850°C, Its kinematic viscosity was found to be about 20% lower than that of the corresponding NaF-ZrF ,-UF , mixture. 8. Radiation Damage The high-temperature forced-circulation fluoride- fuel loop recently operated in a horizontal beam hole in the LITR was examined metallographically. Corrosion of the Inconel tubing by the circulating fluoride-fuel mixture was found to be fow and to be substantially the same as that found previously in capsules exposed in the MTR. No increases in corrosion attack because of irradiation and no other unusual effects were found. In the portion of the loop that showed the maximum corrosion, the average penetration was 1 mil and the maximum was 2.5 mils. In general, the changes in the Inconel were those expected in specimens sub- jected to the heat treatment imposed by operation of the loop. The average corrosion for the entire loop was 0.5 mil, and no deposits of mass-trans- ferred material were found, The fuel circulated in this loop was NaF-ZrF --UF4 (62.5-12.5-5 mole %). The fission power generated in the fuel was calculated to be 2.8 kw, and the maximum power density was 0.4 kw/cm3, The miniature in-pile loop was operated in a “vertical position in the LITR, but the experiment was terminated after about 30 hr because a faulty’ pump motor prevented the maintenance of steady fuel flow. The test was incomplete as a corrosion study, but it was possible to make a fairly thorough 1 ” T T g% study of the in-pile characteristics of the loop. The necessary design modifications are being made, and a new loop is being fabricated, The Reactor Experimental Review Committee has approved the insertion of the pressurized stress-corrosion apparatus in HB-3 in the LITR, and specimen assemblies for a series of tests are being filled with fuel. Bench tests are in progress on an apparatus for insertion in the MTR that is designed to test creep in two nonfuel atmospheres. An MTR (tensile) creep test apparatus irradiated during two reactor cycles is being returned to ORNL for postirradiation measurements., The bench equivalent of this apparatus has been assembled and tests have been started. The maximum high-energy neutron flux in HB-3 of the MTR was measured to be 3.1 x 103 fast neutrons/cm2.sec, and the thermal-neutron flux was found to be 2.3 x 104 neutrons/cmZ.sec. A flux-depression experiment in HB-3 indicated a lack of sensitivity of flux depression to the kind of nuclear absorber used. The power to be ex- pected in the MTR in-pile loop was estimated from the measurements to be 31 to 36 kw. Analyses of reactor-grade beryliium obtained from The Brush Beryllium Co. and the R. D, MacKay Company showed that the predominant source of gamma activity after long irradiation followed by a few days decay is Sc48, The quantity of scandium present is so small that it cannot be found by chemical analyses with a limit of detection of 200 ppm. f9. Analyhcal Chemlstry of Reactor Materials Modifications of the n-butyl bromide method for the determination of oxygen in sodium were evalu- ated. The modifications included the addition of a column of silica gel and diatomaceous earth for the rapid purification and desiccation of re- agents and an lmproved apparatus in which the ‘reaction between sodlum and butyl bromide could be carried ouf in an afmosphere of argon, Although 7 the oxygen content of the mu|or|'ry of the samples L which were used in 'reshng these modn‘lcuhons_‘ - - ‘was in excess of 200 ppm, concem‘ratlons of the = order of 20 ’ro 40 ppm of ‘oxygen were found m' o 4specro|ly prepared sodium, :Tests were made of fhe method for the determina- tion of oxygen in sodium by titration of the Nazo,_' that remains after vacuum distillation of the sodium metal. An apparatus was constructed that was similar to one developed by the Argonne National PERIOD ENDING SEPTEMBER 10, 1955 L.aboratory. Preliminary results on sodium sampled at 1200°F showed an oxygen content of the order of 50 ppm. Since samples of sodium at high tem- peratures can be obtained with this apparatus and since fow levels of oxygen can be detected, the apparatus is to be attached directly to a forced- circulation high-temperature-differential sodium loop so that analyses can be carried out during operation of the loop. Development of a volumetric method for the de- termination of zirconium in fluoride salts was completed, In this method zirconium is converted to a stable complex by the addition of an excess of disodium dihydrogen ethylenediaminetetraacetate (EDTA) to a dilute H2804 solution containing zirconium, The excess EDTA is ftitrated with trivalent iron to a disodium-1,2-dihydroxybenzene- 3,4-disulfonate end point at a pH of 4.8, Titration can be conducted in the presence of as much as 0.1 M of fluoride ion by first complexing the fluoride ion with beryllium, Slight modifications in the procedure make the method also applicable to the determination of zirconium in the presence of moderate amounts of trivalent iron, divalent nickel, and trivalent chromium. The apparatus for the determination of uranium metal in mixtures of fluoride salts by decomposi- tion of the hydride in an atmosphere of oxygen at reduced pressures was modified to include two combustion tubes so that one sample can be oxi- dized while a second is being converted to the hydride. Analytical assistance was given in a study of the rate of elimination of atmospheric gases from a dry box with argon. The most efficient flushing action was found to be the fairly rapid injection of argon at the bottom of the dry box, without supple- mentary agitation. With an argon flow rafe of 25 cfh, the concentration of oxygen in the atmosphere of a 21-ft3 dry box was reduced by a factor of 100 by flushing with two volumes of argon. Investigation was continued of the application of the bromination method to the determination of oxygen in ZrF ‘and its mixtures with alkali-metal fluoride sal'rs._ Incomplete removal of oxygen wdas observed for samples of pure ZrO, after bromina- tion for 6 hr at 950°C, “In the bromination method for the determination of oxygen in metal oxides, the oxygen is converted to CO and then oxidized to C02 for measurement. A method for the direct measurement of CO was studied in which the CO is absorbed in an aqueous ANP PROJECT PROGRESS REPORT solution of PdC|2 and KCl. The net increase in - hydrogen ion concentration of this solution is a function of the CO present. Excellent titration curves were obtained only when an amount of Kl in excess of ‘the PdCI present was added to the _soluhon prIOI’ to h’rroflon with a standard base. ‘IO. Recovery and Reprocessing of Reactor Fuel A _,rey_rl_ewr of the deslgn and construction prob- - lems involved in the completion of the pilot plant " for fhe fe'coikéfy of fused-salt fuels has indicated ~that a construction completion date near the end of February 1956 will be more realistic than the December 1955 date given previously. An engi- neering flow shee'r was issved, and approximately 65% of the process equipment items are on hand of are in some stage of procurement or fabrication, The dump tank containing the ARE fuel was moved, uneventfully, from the ARE building to the pilot plant building. Methods have been de- : 4fiV|sed for removing the fused salt from the dump ‘tank and from other types of containers for charg- ing into the fluorination vessel. Direct-resistance heating of transfer lines was found to be satisfactory for preventing plugging, except at fittings, where supplemental external heating will be required, A freeze valve was de- signed for closing the transfer lines to and from the fluorinator, After 15 cycles of freezing and thawing, this valve, when frozen, held against a pressure of 20 psig without leaking. An improved procedure for decontamination of the UF6 product of the fluorination step was developed which involves the absorption of the UF , on NaF at 100°C and desorption by heating to 400°C, with the product gas passing through a second bed of NaF before collection of the UF, in a cold trap. Since in this two-bed process, in contrast to the previous process in which a single absorbent bed was used, the fission products never enter the product-collection system, decontamination factors of greater than 105 were obtained in re-used equip- ment. Preliminary results indicate that nitrogen may be used as a sweep gas in both the fluorina- ~“tion and the NaF absorption and desorption steps Sote reduce the amount of fluorine required for 'processmg. s . ,' PART Hl SHIEL DING RESEARCH ' o, Sh|e|d Design A survey of fhe welghts of spherically symmetric qxj_n{ffishl_el_ds,for_ circulating-fuel reactors was made 10 for a range in dose rates of 0.1 to 10 rem/hr at a distance of 50 ft and a range in reactor power of 100 to 300 Mw. An estimate was obtained for the added weight of an NaK-to-NaK secondary heat exchanger and its shielding, The additional weight was found to vary sharply with the manner in which the dose rate was divided between the "secondary heat exchanger and the reactor and with the absolute value of the sodium activation. The chief sources of radiation in the 300-Mw circulating- fuel reactor for the NJ- 1 power plant were determined. New data recently obtained at the TSF and 'flie LTSF are being used in a parametric shield weight study for a 300-Mw circulating-fuel reactor in which the important reactor dimensions are varied. Differences between the shield test mockups and the design reactors are accounted for 'o_h“the' _boé_is of the present understanding of the sources of radiation in each. As a result, shield weight dependence upon reactor and shield d|mens:ons and materials can now be calculated with greater certainty, The results obtained to date indicate that divided shield weights can be significantly reduced by increased shield-shaping based upon TSF and LTSF data and analyses, 12. Lid Tank Shielding Facility The static source tests of the second series of the circulating-fuel reflector-moderated-reactor and shield (RMR-shield) mockup experiments have been completed. The final tests included neutron und gamma-ray measurements beyond the mockups to determine the effect of placing an intermediate or high atomic weight material immediately behind the beryllium reflector, varying the thickness of the reflector, and distributing the lead gamma-ray shield in borated water, RMR-shield, little, if any, welght saving results from adding bismuth to the outer region of the reflector rather than using lead in the shield. The addition of a 2-in.-thick layer of copper in the same region was insufficient to effect an appreci- able weight saving, but there was ev:dence that there might be enough self-absorption of ccpfure gamma rays in a 4-in,-thick copper layer to show a valuable weight saving, thickness (8, 12, and 16 in.) did not have an appreciable effect, : The study of distributing the lead gamma-ray shield in borated water showed that, for lead thicknesses up to 5 in., there would probably be For a typical 300-Mw VYarying the beryfhum. [ .!),‘_i . ’ ' L) . . . - —— An T o completed no weight saving as a result of distributing the lead rather than placing it in one piece but that there might be an appreciable weight saving as a result of distributing the lead beyond the first 5-in. layer, The secondary gamma-ray dose rate produced in the lead and borated-water shield fell off at the same rate as the thermal neutron flux ~ and thus was apparently caused by thermal-neutron captures in the shield. ~Sodium activation tests were performed to de- termine the activation of the coolant in the heat exchanger region as a function of the heat ex- changer thickness, the boron curtain thickness and distribution, and the reflector thickness, Results of representative tests showed that the sodium activation in the heat exchanger was increased in going from a 4-in. thickness to a 6-in. thickness. The probability of escape of the resonance neu- trons was reduced by the increased thickness; the probability may be increased, however, by dis- tributing the boron curtain through the heat ex- changer region. An increase in the reflector thick- ness from 8 to 12 in. decreased the sodium acti- vation by 80%. A gamma-ray shield of copper placed between the beryllium reflector and the first boron curtain increased the sodium activation by a factor of about 6. 13. Bulk Shleldmg Fucull'ry A part of the experiment designed for determining the gross fission-product gamma-ray spectrum was completed. Small samples of enriched uranium were irradiated in the ORNL Graphite Reactor for time intervals ranging from 1 to 8 sec, and the gross fission-product photon spectrum was studied by using the mulhple-crysfol gammo-ray specfrom- eter. The decay of six energy groups, covering PERIOD ENDING SEPTEMBER 10, 1955 from the reactor were integrated. The integrated dose {0.49 mrep/hrew) compared surprisingly well with the total dose measured by the Hurst-type dosimeter (0.52 mrep/hrew), Measurements were also made through 70 cm of water at a point 19.6 c¢cm from the center line of the reactor and through 5 cm of water on the center line of the reactor. In all cases the measured dose remained constant, within the statistical devia- tion, when the collimator was pointed at the active lattice of the reactor. 14. Tower Shielding Facility The results of Phase | of the TSF differential shielding experiments have been incorporated in the development of a procedure for optimizing the neutron shield of a divided aircraft shield. In this optimization procedure the neutron shield at the reactor is divided into N conical shells. The thickness of the nth conical shell is then denoted by T, (n=1,2,...,N). Thecrew shield is assumed to be cylindrically shaped, with a rear thickness T, and a front and a side thickness T .. The pro- cedure then consists in (1) expressing both the total weight of the neutron shield and the dose rate at the center of the crew compartment as functions of the T 's, T, and T_; (2) using the method of Lagrange multipliers to obtain the equa- tions which the T ’'s, T, and T must satisfy in order that the weight be a minimum for a specified total dose rate at the center of the crew com- partment; and {3) developing an iterative procedure for the solution of these equations, There are still some gaps in the experimental input data required for the optimization. Where it " has been feasible, these gaps have been filled by extendmg the existing data by qualitative theoreti- the range of 0.28 to 5.0 Mev, was foliowed from 5 to 150 sec after flssnon. lease per fission in the time interval cnd energy” range described was found to be about 1.5 Mev.’ The total energy re- Additional measurements of fast-neutron dose as a funcflon of qngle in a water shueld have been Tower analysis, Shleldmg FdClhty. It is which involves simple ~more meaningful than that reported in the pre- vious ANP Quarterly for which data obtained with the GE-ANP mockup were used. The angular-distribution measurements made on the reactor center line at a distance of 70 cm | The ‘tesulting data were analyzed .~ for use with the shleld ophmlzatlon ‘'studies of 'rhe_'___ felt that thus_ . geometry, is ) for a crew shleld fh!ckness of less fhon 5 cm of " cal considerations of the attenuation processes “involved. An important limitation does exist, how- ‘ever, in the use of this optimization procedure, In the TSF experiments, scattered dose rate meas- or T, smaller Therefore, for T _ and Tr less than 5 cm, “exirapolations must be used Indications are that, for such small thicknesses, the requcn‘lon Iengfhs chcmge apprecmb!y, hence, "it does not appear ‘advisable to use the procedure suremenfs were. nof ’raken for T flmn abouf 5 cm of water.' wa’rer. A neutron shield optimization calculation for a typical reactor and shield configuration was made by using the above procedure, This calculation 11 ~indicated that the procedure is quite satisfactory and yields results which converge rapidly enough for the solution to be obtained in a reasonable length of time by hand calculation. In going from ~ the first to the third iteration, the weight of the calculated shield, in this sample calculation, was reduced from 11.3 to 9.6 tons, 12 A further investigation of the GE-ANP R1 re- actor and crew shield mockups is under way. Measurements of gamma-ray doses inside the crew compartment mockup have been completed, and, at present, a study of the distribution of gamma-ray infensities in air around the reactor shield is being made, ' Part | REACTOR THEORY, COMPONENT DEVELOPMENT, AND CONSTRUCTION ” ‘system; and all work required on roads, grounds, * which design could not be completed for inclusion ‘process lines, and process equipment, . hessee. Their :fh the Chtcago_ Brlcfge & Iron Cq.‘enga 0 1rerquzlre that 1. REFLECTOR-MODERATED REACTOR E. S. Bettis A. P. Fraas ~ W, G, Piper Aircraft Reactor Engineering Division A, M, Perry Electronuclear Research Division AIRCRAFT REACTOR TEST FACILITY The package 1 drawings for the southwest area F. R, McQuulkm are being withheld pending design of the complex Aircraft Reac’ror Engmeermg Division piping and equipment (package 3 work) that will be installed within this area. Final release of the Consfruchon OF‘ the ART Facility has been package 1 drawings for this area is scheduled for divided into three ‘‘packages’” of work. Package 1 October 15, 1955. Plans and specifications for includes alterations and additions to Building ) K bei 4 + ORNL. 7503; construction of the 7503 cell, air duct, package 2 work are being made a stack, adsorber tank, spectrometer facility, and SHIELDING EXPERIMENT FACILITY fuel storage tank; a portion of the electrical power , R. D. Schultheiss . ‘ . Aircraft Reactor Engineering Division and fencing. Package 2 consists in additional 9 S mechanical, electrical, and structural work for Recent tests made af the Tower Shielding Facility indicated that provision should be made for the measurement of the gamma-ray spectrum of the ART as a function of the angle of emission from the reactor shield surface. It was decided that four collimated beams radiating from an auxiliary service and utility equipment, and lines equatorial point at the surface of the water shield up to the cell and to the vent-gas piping system. at angles of from 0 to 70 deg from the radial Package 3 includes the installation, by ORNL direction would serve to give the essential data. forces, of the experimental instruments, controls, One additional collimated radial beam will be available from an equatorial point at the surface of the reactor pressure shell; this beam will be used only during low-power operation. The layout required for providing these beams and the fa- prime contractors who expressed prior interest cilities for measuring them are shown in Fig. 1.1. submitted bids, which were opened August 16. In addition to the facilities shown in Fig. 1.1, a The bids ranged from $765,835 to $869,560, with ~~ gamma-ray dosimeter will be located on the roof bids for the cell included; the cell bids ranged “bovefhefefidor o from $229,000 to $280,000. The contract was pEE awarded on August 19 to the low total bidder, AIRCRAFT REACTOR TEST DES|GN the V. L. Nlcholson Compcny, Knoxv:lle} Ten- S TR | i Included $264,373 for» e in package 1. The work included in packages 1 and 2 is to be performed by an outside contractor. The work items included in package 2 are the diesel-generator auxiliary power supply facility, Drawings and specifications for package 1 were prepared by the K-25 Engineering Division for lump-sum prime contracting. All six prospective Reactor Desngn A P Fracs constructton N ol C buddlng cd i |on, ; _ days, shown in Flgs. T, 24 VT 3 “and T 4 7and Table 1.1 commencing August 29 1955, The cell and gives the key dimensional data. The design of southwest corner installation are to be completed | the pump—expansion tank region, which includes by June 1, 1956. / the sodium-to-NaK heat exchanger, has been I‘// AN M : (\:}5 {;_ ]5 R IR FTENT TET T T TR R e e e i G o ik et ' ANP PROJECT PROGRESS REPORT el RS | 1 L SPECTROMETER l \ ERECIERSGILS ROOM | 'COLLIMATOR TUBES ~=— ///—__ REACTOR \ \\ st e T Fig. 1.1. ART Shielding Experiment Facility. worked out in a fashion which seems to be satis- factory from all standpoints. A one-half scale plastic model of that region has been completed ‘to facilitate ex_qmination' of fabrication, stress, _and flmd-flow problems. Work has started on a . full-scale aluminum model of this same assembly; . with aluminum, the procurement and machining - time will be reduced drastically from the time that - would be required with Inconel, and yet the - fabrication pt ion problems that will arise in the pro- : jif‘i'-f-.f"*"f-'gfil(ui:firfi''o/r': ‘of this model will be the same as those 16 L L e i L e L CELL 7 7 V i to be involved in the fabrlcahonofthe ART]t | is expected that many welding problems will be revealed and that modifications can then '_be made to facilitate fabrication with Inconel. The alu- minum model will also be used for flow tests with - . oo water and stress analyses with strain gages or stress-coat paint. The remaining design work on subassemblies is sufficiently well along fhaf' arrangements for procurement of the Inconel and other parts for the ART began on August 1. Fabrication of the various shells, such as the ORNL-LR-OWG 9178 - 3 . . oo . F B i « ¥ “ >} L C i ol U e e e PERIOD B N e L Y LINER FUEL—TO—NaK HEAT! EXCHANGER | /—\ NaK {COLD) == NaK{HOT) mmp FUEL PUMP REFLECTOR-MODERATOR FUEL TO L PUMP ) i ANNULUS FUEL EXPANSION TANK ISLAND SLEEVE * CONTROL ROD SCDIUM INNER CORE SHELL Ne PUMP - — B SPACER WIRE ,{ Na RETURN-K : 1 . OUTER CORE SHELL Na INLET Na—TO—NaK - HEAT EXCHANGER i i GG THERMOCOUPLE DING SEPTEMBER 10, 1955 o D o 5 , S e T PN T i 7 f‘)\\‘,/"’ i L ¥ “ ! et N e e Pt !y ! . o L ; i < : é il — < i ] £ i - i TN P Y P - L R T ! , SR A \"'\.“‘ l ,;‘;‘ - e vy Fig. 1.2, Vertical Section Through Reactor. 17 I\ T Y RN "TPR N i —— i e TR T TS - e e et o e e g A S T 8 U T e » - ORNL-LR-DWG 8835 Lo T T TE VT LR FUEL TO \, S N <5 TR S N 77 TR A T L s , “pressure shell, refls ticularly time-c “and therefore procureme Thgmcnn and_auxil _ the ART are i .. sign E:]AC hh;cfld |E:tor consists of \'ryj;-)év3fill(‘);:s;'c‘zifil'ess-steel-'cIrqd'-cbpifie“r o (0.0025 in.-0.005 in,—0.0025 in.) fins spcced_ 15 core Units for T wE Fuehte ok Hoot Exchongr Desan R. D. Schultheiss s Ajperaft Réqctor :Eng'ineering Ddi\'rilsiér‘l 'Design calculations and the layout drawings for the main heat exchanger were completed, and a 19 B T I B T T O T v eer o W T S 7 e ST £ TTeT IR TR " I Wy . 0. ORNL-LR-DWG 8837 Ne RETURN FROM MODERATOR s A _ CONTROL ROD =% THIMBLE ISLAND EXTENSION-"| FUEL PUMP BARREL i { | i | i _——FUEL EXPANSION TANK PERIPHERAL RING / / s MODERATOR AND ISLAND \ / Fi.g. 1.4. Horizontal Section Through Sodium Pumps. selection of a heat exchanger was made. The 'i'ig. ‘The design data are presented in Table 1.4, ~design selected is similar to the designs previ- The new layout makes it possible to halve the ously described except that the tube configuration ~ number of heat exchanger tube bundles without . in the vicinity of the header sheets has been doubling the number of jigs. This has the ad- modified so that all tubes in a given layer have vantage of halving the number of NaK pipes ~the “sdm‘e_ shape and can be made with a single penetrating the reactor pressure shell, @y, - ay " PERIOD ENDING SEPTEMBER 10, 1955 TABLE 1.1. REACTOR DIMENSIONS REACTOR CROSS-SECTION EQUATORIAL RADII (in.) Control rod thimble Inside ' 0.750 Thickness ’ . 0.062 Outside - 0.812 Sodium passage Inside 7 0.812 Thickness 0.094 Outside 7 0.906 Beryllium v V o | | Inside ' 0.906 Thickness ' 4219 Outside 5,125 Sodium passage Inside 5.125 ‘Thickness 0.]é5 | Outside - 5.250 Inconel shell (inner core shell) - Inside 5.250 Thickness 0.125 Outside - 5.375 Fuel Inside - .5._3'7"5 Thickness 5,125 Outside 10.500 Ovuter Inconel core shell | | inside 10.500 Thickness o 0.125 Outside ' 10.625 Sodium pessage Inside - ' 10.625 Thickness Coee e 0,094 Qutside 10.719 Beryllium reflector ™~ 7 lnside - » . ‘1,/‘( ;;,;'_m.-;. flA-\-\ 10'7_19 - l— o 10949 2 nconel shell Thickness N » ' ©0.250 Qutside ' 22.0:43 B4C tile inside Thickness Qutside Helium gap Inside Thickness Qutside Quter reflector shell Inside Thickness Outside Spacer thickness Tangent to first heat exchanger fube Tube radius Center line of first tube Eleven 0,2175-in, spaces Center line of twelfth tube Tube radius Spacer Channel Inside Thickness Qutside Gap Inside Thickness Outside Boron- jacket Inside Thickness Outside BAC tile Inside Thickness Outside Helium gap Inside Thickness Outside Pressure shell liner Inside Thickness Outside 22.043 0.375 22.418 22.418 0.020 22.438 22,438 0.062 22.500 0.015 22.515 0.094 22,609 2.392 25.001 0.094 0.015 25.110 0.125 25.235 25.235 0.040 25,275 25.275 0.062 25.337 25.337 0.313 125.650 25.650 0.020 25.670 25.670 0.375 26.045 21 T TR o G S T T ATy YT T IR T Y " "ANP PROJECT PROGRESS REPORT TABLE 1.1. (continued) Vsc',%;l.ium passage , UIAri-sr-i:de B Th|ckness . L Ou]f;ide ' Pfessure_ SHeIA-[ . [nslde . Thickness ~ CORE ~ Diameter {inside of outer shell at “équater), in. |s land ou t5|d e dla r:hefer ,in, Core inlet outside diameter, in, iametet, in, inlet area, in. 2 Core equatorial cross-sectional areaqa, in.2 MODERATOR REGION Volume of beryllium plus fuel, £r3 Volume of beryllium, £3 Cooling passage diameter, in. Number of passages in island Number of passages in reflector FUEL SYSTEM Fue!l volume, £t3 In 26-in.-long core In inlet and outlet ducts In expansion tank when 1/2 in. deep In heat exchanger ‘In pump volutes Total in main circuit Fuel expansion tank Volume, £43 Widfli, in, Length, in. SODIUM SYSTEM (f13) Sodium volume © .7 In annular passages 7 ""*"In heat exchanger 26.045 0.125 26.170 26,170 “1.000 27.170 21 10.75 1 - 6.81 58.7 ' 256.2 28.2 24.99 0.187 100 288 3.21 1.41 0.08 2.84 0.84 8.38 0.5787 13.625 32.500 1.1 0.165 In island tubes In reflector tubes In inlet and return piping In pumps and volutes In first deck In second deck In external piping In expansion tank Total sedium volume FUEL.TO-NaK HEAT EXCHANGER Tube data, in. Center-line spacing Qutside diameter Inside diameter Wall thickness Spacer thickness Mean length Equatorial crossing angle Inlet and outlet pipe, in. Inside diameter Qutside diameter Header sheet, in. Thickness Inside radius Fuel volume, ft3 Number of tube bundles Number of tubes per bundle, 12 X 24 Total number of tubes Latitude of north header center line LLatitude of south header center line PUMP--EXPANSION TANK REGION Vertical distance above equator, in. Floor of fuel pump inlet passage Bottom of lower deck Top of lower deck Bottom of upper deck Top of upper deck Top of sodium pump volute Center line of fuel pump discharge Center line of sodium pump discharge Top inside of fuel expansion tank Inside of dome 0.064 0.233 0.077 0.175 0.260 0.308 0.019 0.042 2.45 0.2175 0.1875 0.13735 0.025 0.030 72.000 26°20° 2.375 2.875 0.375 3.812 2.84 12 288 3456 41°30” 47° 17.500 19.125 19,625 24.000 24.500 27.750 21.500 26.125 29.500 29.875 ) ™ o PERIOD ENDING SEPTEMBER 10, 1955 TABLE 1.1. (continued) Qutside of dome Top inside of sodium expansion tank N Top outside of sodium expansion tank Top of fuel pump mounting flange Top of sodium pump mounting flange FUEL PUMPS Center-line épacing, in. Volute chamber, in. Width Length "~ Height Impeller speed, rpm Estimated impeller weight, |b Critical speed, rpm Shaft data, in. Diameter Ovethang Over-all length Outside diameter between bearings Qutside diameter below seal Distance between bearings, in, Impeller data, in, Piameter Discharge height Inlet diameter Lower journal bearing outside diameter, in, Thrust bearing height from equator, in, P - Number of vanes in impeller o - Diameter of bottc ‘ring, in. - Centereline spacing, in. Volute éhamber, in, Width - Diameter of top pos momngrmg,m. o *Outside diameter of top flange, in, 20.875 24.312 34.812 47,000 50.220 21.000 13.625 32.500 4.375 2750 11 6000 2.250 14.750 31.500 2.375 2.250 12.000 5.750 1.000 3.500 13.400 48.187 Length Height Impeller speed, rpm Estimated impeller weight, Ib Critical speed, rpm Shaft data, in. Diameter Over-all length QOutside diameter between bearings QOutside diameter below seal Distance from center line of lower bearing to center line of impeller, in. Distance between bearings, in. impeller data, in. Diameter Discharge height Inlet inside diameter Lower journal bearing outside diameter, in. Thrust bearing height above equator, in. Number of impeller vanes Diameter of top positioning ring, in. Diameter of bottom positioning ring, in,. Outside diameter of top flange, in, SODIUM-TO-NaK HEAT EXCHANGER Tube data, in. Center-line spacing Qutside diameter Inside diameter Wall thickness Spacer thickness Mean length Number of bundles Number of tubes per bundle, 15 x 20 Total number of tubes Inlet and outlet pipe, in. Inside diameter QOutside diameter 8.687 2.500 2880 10 6000 2,250 31.500 2.375 2.250 13.300 12.060 5.750 0.500 3.500 3.400 51.907 10 6.200 6.190 10.000 0.2175 0.1875 0.1375 0.025 0.030 28 300 600 2.375 2.875 23 e e e ANP PROJECT PROGRESS REPORT TABLE 1.2, RADIATOR DESIGN CONDITIONS | Main | Auxi'iidry Power, Mw 55 Y NaK inlet temperature, °F 1500 00 NaK outlet temperature, OF 1070 900 ~Total .N(c!'(__frlo\'.v at average temperature, cfs 10.45 g0 - Alr inlet temperature, °F B 100 w00 - ;-'-"Air' o:ufr_‘|“e'r‘_tem.;.:erafure, °F | 1128 N 810 ~“Total air flow at inlet conditions to blower, cfm 179,000 22,800 ~ Air pressure drop across radiator, in, H,0 5.58 . 5.84 TABLE 1.3. RADIATOR DESIGN DATA Main | ‘_7:'_AL|'xE|i-c_1ry | " Face area, ft2 6.25 ' 6.25 Mean free area, ft2 3.66 3.66 Air mass velocity, Ib/ft2.sec 3.46 3.71 Collar plus tube wall thickness, in. 0.035 0.035 Fin area, f2 922 922 Collar area, ft2 5.2 5.2 Inside tube area, ft2 42.7 42.7 Mean tube area, ft2 44.2 44.2 Number of tubes 360 360 Number of rows 8 8 Air Reynolds number 1321 1590 NaK flow area, in.2 5.34 5.34 NaK Reynolds number 91,400 111,000 NaK mass velocity, Ib/ft2.sec 820.0 1211 Core Flow Studies W. T. Furgerson G. D. Whifmon E. C. Lindley W. J. Stelzman A. M. Smith J. M. Trummel Aircraft Reactor Engineering Division Two approaches to the core hydrodynamics problem are being investigated. Both make use ~of a vortex sheet in the annulus between the “island ‘and reflector in an effort to get a high o degree of mixing. In the first system the vortex ~~ _axes parallel the island, while in the second they spiral helically downward around it. In both systems the two fuel pump volutes discharge tangentially into the core inlet to give a system that is insensitive to the one-pump-out condition, Fight series of tests have been made on the axial vortex system in the metal core rig. The tests constituted a systematic development of an inlet-guide-vane and turbulence-generator design ‘which would produce radial velocities of sufficient magnitude to keep the boundary-layer fluid mixed with the free stream, | - PERIOD ENDING SEPTEMBER 10, 1955 A EERE TABLE 1.4. FUEL-TO-NaK HEAT EXCHANGER DESIGN DATA Tube diameter Number of tubes per bundle Number of bundles Tube center-line spacing Tube wal thickness Tt‘Jbe array, square pitch? 'Meon 1u5e |éngth | Fuei'?émper_aft.)re range NaK temperature range Fuel pressure drop through heat exchanger NaK .préssure drop thrbugh heat exchanger Fuel Reynolds number in heat exchanger NaK Reynolds number in heat exchanger Fuel flow rate? NaK flow rate? Fuel volume in heat exchanger NaK volume in heat exchanger tubes (not ihcluding headers) Heat exchanger thickness (includes 0.015-in. side-wall clearance) Limiting combined tube stresses® at tube wall temperatures Log mean temperature difference Estimated maximum tube wall temperature, neglecting secondary Eeoting effects Fuel mixture NaF-ZrF 4UF, {50-46-4 mole %) heat transfer coefficient NaK (56% Na—44% K) heat transfer coefficuent Capacity at design operating condlhons A Inconel surface (tubes and channel) in contact wrth fuel Inconel surface in _contact wflh NoK o |ncone| volume of tubes in heot exchanger o 0.1875 in. 288 12 0._2]75 in. 0.025 in. 12 x 24 5.95 ft 1250 to 1600°F 1070 to 1500°F 43 psi 41 psi 4135 144,000 2.96 cfs 10.45 cfs 2.84 #t3 2.14 #3 2.61 in. 1125 psi at 1135°F 220 psi at 1535°F 136°F 1535°F 2090 Btu/hr+ft2:.°F 18,200 Btu/hr-ft2.0F 55 Mw 160,000 in.2 (1110 £12) 107, 500|n 2(746 ft2) 'i3170|n. (1 83ff3) o - velocn‘y profll . with swurl chonflaer ":aCalcul'dfiorJ\s ,"b At meqn op ‘ cmng CTube sfre ses’ “The effect of one design is shown by the axial ,of"“ Flgs. 1.5, 1.6, and’ ] 7'” ‘ dota obtained for th inlet only, that is, ho inlet _wh:ch component. Flgure ]5 pre rotational component centered on the core axis gradient is ’:Qrcdlenfs, which,” lS cpproxlmately three tlmes the‘hax:al " This gives rlse to strong radial as a resul'r of fluid ’-frlctlon, induce an adverse axial pressure gradient gw‘de vanes or turbulators. The flow has o along the island wall. This induced axial pressure ‘additive to the already existing 25 T T I T s ikl ANP PROJECT PROGRESS REPORT ORNL-LR-DWG 9348 STATION < STAT\ON 8 | NO DATA TAKEN BELOW STATICN 6 ' sTllT\ON ! E.Q,UATOR STATION 5 e ¢ - 2] a o > C 2 wl > o STATION 3 STATION 1 Fig. 1.5. Axial Velocity Profiles from Test Series 1. gradient caused by the divergence of the core, and thus large areas of reverse flow occur next to the island. The results of tests of the core with inlet guide vanes for eliminating the rotational flow com- ponent are presented in Fig. 1.6. The induced axial pressure gradient was removed, and the _amount of flow reversal along the inner wall was decreased. As in the first series, the flow was ~essentially two-dimensional; that is, no appreci- -able radial component existed. Turbulators were added to the previous con- i i‘igbratibh for another series of tests. The tur- '_"_'__*‘V'bu]a'rors were expected to generate radial velocity - 'ffcomponems ‘which would carry boundary-layer fluid - fmto the mlds’rrecm and vice versa. It can be seen ORNL-LR-DWG 9349 EQUATOR — STATION 5 INLET GUIDE VANE DETAILS NO DATA TAKEN ABOVE STATION 7 OR BELOW STATION 4 o q- —— o Q. = - o B O O 0 [} > o Fig. 1.6. Axial Velocity Profiles from Test Series 5. | from Fig. 1.7 that the amount of flow reversal was further reduced. ' In another series of tests (series 8) flow re- versal was eliminated from station 6 downward by use of a greater radial velocity component. The configuration of series 8 was used for two brief tests that simulated the one-fuel-pump-out condition. Preliminary results’ md:cate that flow conditions change very litile, ’rhe percentage of flow separation remaining approxmately the same as for the two-pump condition. Data are taken from the metal core test rig by means of wall static pressure taps and claw probe traverses. The latter read total pressure and flow direction but are limited to measuring flow which is two-dimensional. As stronger turbulators are designed and radial velocity components become greater, accurate data will be mcreasmgly more " T T , 3t PERIOD ENDING SEPTEMBER 10, 1955 i L kgt < electrolyte injected was a concentrated solution . ORNL-LR-DWG 9320 . .. of sodium chromate. Injections were made manually by using a 30-ml glass syringe. Some care was required to obtain adequate insulation and to seal arcund the two wires of the conduc- tivity probes. A satisfactory arrangement employs Kovar tubing and wire with a glass insulator and seal As now used, the probes consist of a /16"'"‘ -dia Kovar tube with two 0.025-in.-dia Kovar wires. The wires afe separated by approximately }/8 in. and project about % in, from the seal. The total length of the probe is 9 in. Some corrosion of the probes occurs, but probe life is considered to be satisfactory. INLET GUIDE VANE AND TURBULATCR DETAILS The resistance bridge is a Wheatstone bridge with fixed legs of 10,000 ohms each; the third leg is adjustable to match the electrolyte resistance sensed by the probe, which is the fourth leg. A 45-v battery supplies the bridge current. The of the water, and therefore only a change in NO DATA TAKEN .. . . . ABOVE STATION 7 conductivity is passed as a signal to the ampli- OR BELOW STATION 4 fiers. Conductivity experiments have been made on both the aluminum mode! and the transparent plastic model. The water flow rate is approxi- mately two-thirds the fuel flow rate for the Reynolds number expected with the fuel flow. Perhaps the most pertinent values derived from ‘ Lo i the tests are the estimates of transit times, For Fig.. 1.7. Axial Velocity Profiles from Test example, data were taken with the probes located Series 6. _ , o very near the inlet and outlet of the aluminum ' R : P model core, and, if time is counted from the first ‘ difficult to obtam.' Two other hmltahons to the __w__appearance ‘of added salt at the inlet probes, the metal core rig exist in that fhe probes “ {ime of appearance of the salt at the outlet probe average values and do not respond to transients, " is ds shown in Fig. 1.8. The fastest transit time . Qnd surveys‘ are I|m|fed>fo fwo po|nfs 9 deg Qparf ) ;_WQS O ?lhsec, whilafhe S‘IOWGSf medsured transit ' ; ' as ab9u1,2.8_ sec. There IS a ||mlt to the L VELOGITY (fps) .7 doubtedly, some small arount of salt passes after ~ the time of no sngna[ on the Brush recorder. The "":mean fransit time, compu’red as. the quohem‘ °f plastic core = »fransn’"h_rmem acc rately. Howevér, fhe mmlmum 'duchwty o dran me i ... The apparatus’ used includes “two conductlwtyd”-"Y"'frang;’r time was found to be 0.35 sec, and, by L -~ probes, two resistance bridges, two Brush ampli- extrapolation, the maximum transit time was esti- ' fiers, and a two-channel Brush recorder. The mated to be at least 3.2 sec. LT 27 bridge can be balanced for any initial conductivity sensitivity of fhe measurlng apparatus “and, un- systen{ is"s small the sa[’r was reCIrauiated rapldly, ) T o Saki e ks M i i ANP PROJECT PROGRESS REPORT - ORNL LR DWG 9321 7 100 Q oo w wy oy g © ® RUN f _c* z O RUN 2 o > 80 < I / wi Q e wl -J &3 60 o 5 E / O - |_DURATION OF . 53 SIGNAL ON / 23 40 |«NLET PROBE a a = / 5 // u 20 and by Pratt & Whitney Aircraft to be 0.35% in reactivity for 1% in density.? Based on these figures, an average reactivity change of —-1.5% is predicted. Data from the high- fempérafure critical experiment indicate (AM/M)/(Ak/k) to be about 7. Thus a change in critical concentration of 10.5% is anticipated as a result of the reduction of the beryllium density. | The effect of thermal-neutron absorptions in the sodium coolant was estimated by comparing the calculations of the Curtiss-Wright Corp.> for Inconel-lined and unlined cooling holes. The penalty in uranium concentration due to the Inconel was reduced in the ratio of the macro- scopic thermal neutron gbsorption cross sections of the sodium and the Inconel. When allowance was made for the greater number of cooling holes presently planned for the ART, the increment of fuel concentration required to compensate for the sodium in the reflector was 5.6%. The effect of the additional beryllium in the reflector of the high-temperature critical experi- ment has not yet been satisfactorily computed. This is due, in part, to the irregular distribution of the added beryllium and, in part, to some uncertainty regarding the dependence of reactivity on reflector thickness. Whether the entire re- flector volume is considered or only the portion between two planes 1 ft above and below the equatorial plane of the reactor, the beryllium in the experiment was about 3 in, thicker, on the average, than the beryllium in the design reflector of the ART. According to the parametric studies of Curtiss-Wright Corp.,> such a decrease in reflector thickness over the whole surface of a spherical reactor would increase the critical con- centration by a factor of 1.26. Results of the cold critical experiments, however, indicate that removing 3 in. of beryllium over the region ex- tending 1 ft above and below the reactor mid-plane 3c. B. Mills and H. Reese, Jr., Design Study of an ANP Circulating Fuel Reactor, WAD-1930 (Nov. 30, 1954), D, G, Ott and A. Berman, private communication, SH. Reese, Jr., S. Strauch, and J. T. Mihalczo, Geometry Study for an ANP Circulating Fuel Reactor, WAD-1901 (Sept. 1, 1954). € ¥ % i ol ki s —— g - w oy should increase the conceniration by about a factor of 1.12. The true effect is believed to lie between these extremes. ~ The over-all factor by which the critical con- centration of the ART is likely to exceed that of the high-temperature critical experiment is _dbtained by multiplying the four factors together. The result is F = (1,2)(1.])(],06)(1912) = 1.56 , if the low estimates for control rpd allowance and reflector size effect 'qr'é; ‘empléyed, or F o= (1.25)(L1)(1.06)(1.26) = 1.84 , if the high estimates are used. Since the clean critical concentration of the experiment was 2.9 mole % UF , the critical conceniration of the ART is expected to fall between the limits 4.6 and 5.4 mole %. Some multigroup calculations are to be undertaken, in the near future, which should help to establish the critical concentration of the ART somewhat more reliably. R. R. Bate, L. T.’Erinstei}nr, and W, E, Kifiney, The Three-Group, Three-Region Reactor Code for Oracle, ORNL CF-55-1-76 (Jan. 13, 1955). PERIOD ENDING SEPTEMBER 10, 1955 Multigroup, Multiregion Reactor Calculation W. E. Kinney Aircraft Reactor Engineering Division A new multigroup, multiregion reactor calcu- lation is being programed for the Oracle, By taking the consistent P, approximation to the Boltzmann equation, group equations have been developed and lethargy dependent coefficients have been put into a form suitable for coding. In the treatment of thermal neutrons, both neutron and moderator temperatures will be considered. The theory for the inclusion of shells and for the spatial integration of the group equations is the same as that described previously.b The code will compute fluxes as a function of one space variable in slab, cylindrical, or spherical geometry. As presently planned, it will allow up to 125 groups and 125 regions. The calculation may be iterated on the concentration of any specified element to obtain a multiplication ‘constant of unity, and self-shielding factors will be available. Adjoint fluxes may be computed, if desired. 35 ANP PROJECT PROGRESS REPORT 2. EXPERIMENTAL REACTOR ENGINEERING H. W. Savage E. S. Bettis Aircraft Reactor Engineering Division The difficulties encountered during the installa- tion of 1he MTR in-pile loop and in startup of the system are presented, and the modifications being made in the loops now being fabricated are de- scribed. The operating conditions for the 22 fused- salt—Inconel forced-circulation loops operated durmg the quarter are presented, as well as the operating conditions for 9 forced-circulation loops “operated with sodium in Inconel or in stainless “steel tubing. A new test loop is described with which more c:cciirm‘e information on the oxygen content of fhe sodlum can be obtained during R operohon. Two stands for teshng ART pumps were de- veloped ‘and tests of pump seals were made. The tests performed with intermediate heat exchanger test stand A are described, as well as the smali heat exchanger tests, The apparatus being built for tests of the thermal stability of the ART outer core shell is described. Also, a design for Inconel strain-cycling tests is presented, Several designs for cold traps for removing oxides from sodium and NaK are presented, along with designs of plug indicators for detecting and meas- uring the oxide content, IN-PILE LOOP DEVELOPMENT AND TESTS D. B, Trauger Aircraft Reactor Engineering Division Loop Installation C. W. Cunningham Aircraft Reactor Engineering Division The instrument panel for the MTR in-pile loop was installed on the first level balcony on the reactor north face. This location is advantageous in that it is above the activity on the main floor and relatively close to the HB-3 beam hole. Pro- vision of a central balcony extension for the oper- ator enabled him to easily observe the instrument and control panel in the somewhat restricted space, The additional instrument panels and cabinets were Iocated on balcony extensions at each end of the instrument and control panel. " The auxiliary equipment and the loop, on its cradle, were placed on the main floor, largely 36 under and adjacent to the east face stairway. Interconnecting tubes and wires were protected by running them in troughs hung beneath the bal- cony and the stairway above head level. The tubes and wires to the loop were lifted into these troughs after the loop was inserted into the beam hole. A means for flux compensation had to be pro- vided, since the flux profile at the HB-3 beam hole was not known with certainty, A loop retractor mechanism was built and was mounted in the HB-3 cubicle to permit withdrawal of the loop plug 6 in, from the fully inserted position. This device permits adjustment of the loop nose position in the tapering flux region and, thus, variation of the loop power level independently of reactor opera- tion. The retractor also serves as a safety device. By withdrawing the plug 6 in. and reducing the process air flow, reactor operation could continue in the event the in-pile loop experiment had to be operated on the limited, emergency, cooling-air supply. The ability to preset the position of the plug greatly reduces the risk of freezing or over- heating the loop during the reactor startup and shutdown, Orderly arrangement of lines and equipment in the cubicle presented a difficult problem. The lead shields, retractor mechanism, tubing cutoff block, tubing and electrical wires, and hoses almost completely filled the available cubicle space. The problem was further complicated by the movement required for retraction. A workable arrangement was found by trial and error movement of the lines and tubes into various coiled configu- rations. The water hose had fo be carefully routed to eliminate excessive strain on the quick-discon- nect fittings provided to eliminate the leakage of radioactive process water, Loop No. 1 Cperation L. P. Carpenter D. W. Magnuson P. A. Gnadt Aircraft Reactor Engineering Division D. M. Haines Pratt & Whitney Aircraft The first MTR in-pile loop was completed on June 20, and it was shipped, by air, to the MTR il o “This r revision wds facility at NRTS. It successfully passed the pre- operational checks required by the MTR Reactor Safeguards Committee, and it was then inserted into the HB-3 beam hole from the special loading cradle supplied as part of the experiment, Fuel e[ements adjacent to the beam hole were removed for the insertion, since no shielding was provided. Although a rather high radiation beam was meas- ured adjacent to the in-pile loop plug shield, it was well collimated, and the insertion proceeded rapidly and smoothly without the coffin, . The startup of the loop proceeded systematically through pump operation and preheating of the fuel and the piping. At the final step, melting of the freeze line and charging of the loop, the heater for the freeze line was found to be inoperable. An internal short, to ground, had developed after the preoperational checkout. Efforts to clear the short were unsuccessful, and it was impossible to melt the line by increasing the power to adjacent heaters, This terminated the loop operation, and the loop was removed from the beam hole for return to ORNL. Since this loop had been reworked re- peatedly during the initial assembly, it was deemed to be irrepairable and was therefore cut up for evaluation, The short was fo}uhd in a nipple, or extension, from the pump bulkhead to the glass seal for the power leads. Braided glass insulation had become frayed, apparently during assembly, and the copper lead wire was eprsed ‘Mechanical separation befween the copper wire and the nipple probably existed durmg the checkout but rnovement due fo _ of the thermocoup tion, Experience with the flrsf ‘two Ioops shoulcl provide adequate information for en‘abhshmg heat- ing procedures, ;lw'ro tha'r of 'rhe in- -pile Ioop. _fefm'"qfed bY a sudden pump stoppage caused by :..;.,"h‘e c‘CZCUN’!U'fl'fIQr\ of fuel along the shaft in the me'ral _surface, -':by a more ilgh’rly etc ed surfuce, was SUff'C'e"”y hlgh equxvclent to an increase of about 13 cm3 - ;"‘of flu wfllnger PERIOD ENDING SEPTEMBER 10, 1955 Horizontal-Shaft Sump Pump J. A, Conlin Aircraft Reactor Engineering Division The difficulties previously encountered with the shaft seals of the horizontal-shaft sump pump have been corrected. The original seal used a thin, brass bellows, which failed mechanically. It was replaced with a stainless steel bellows, which serves both as the flexible member of the seal and the loading spring, It was necessary that the beliows serve as the loading spring because the combined spring loading of the steel bellows and a spring would have been excessive. However, the spring-loaded bellows caused chatter between the graphite nose and the mating seal ring, and the graphite crumbled. The installation of friction dampers, in the form of spring-loaded steel plugs that pressed radiqlly against the outside of the seal nose, eliminated this difficulty. The maximum gas diffusion leakage rate for this seal has been found to be 100 ppm of argon dif- fusing from the pump sump into the helium in the bearing housing. The flow rate of both the helium and the argon is 700 cfh, Satisfactory seal leakage rates could not be obtained consistently with the initial drip lubrication system; so the oil level in the bearing housing was raised until the lower edges of the running faces of the seal were im- mersed, This provided a better oil film on the seal mating faces, and satisfactory sealing condi- tions were obtained. A prototype model of the in-pile pump operated satisfactorily, with the fuel mixture NaF- -ZrF ,-UF (53.5-40.6.5 mole %) as the pumped fluid, for 173 hr at 1400°F in an isothermal loop identical Operahon was then Id region of the pump. A postrun ‘examination 'md»lrcated that there had been two levels of fuel ‘fl"u-e sump.‘ The first level was ‘at 'rhe normal p opercn‘mg po:nt ds indicated by an etched The se_cond level, as evidenced T 'd, fo reach ’ro above fhe bo'r'rom of fhe shof’r: ' to collect ulong “the shaft cnd ultamately resulted “in pump stoppage. “The change in sump level probably occurred the day before the pump stopped. - 37 ANP PROJECT PROGRESS REPORT An m’rerruphon in the plant air supply thcn‘ was bemg used to cool the fill-tank freeze line caused “the fill-line temperature to rise to above the melhng point of the fuel and the indicated fill- __tcmk temperoture to increase about 25°F due to the absence of air movemenf in its v:cmlfy. The | fill-tcnk tempercture rlse, plus any gas evolution ,frorri V'rhe fuel, could have increased the fill-tank gas’ volume sufficnenfly to force fuel into the ~'pump”and flood the sump. A fill-tank temperature “tise of 35°F would hove, alone, caused sufficnen’r w’_:expcnsmn of the fuel to account for the 13-cm® ‘displacement. This type of failure could not occur “with the MTR in-pile loop assembly, because the _ freeze hne wnll be cooled by its proximity to the - '4_‘water |ocket of the Ioop. = Oll |rradmt|on .7 D. M Hames Prat’r & Whltney Alrcrcft Samples of Gulf Hcrmony ““A" oil were irradiated at the gamma facility of the MTR to determine the suitability of this oil for use in the lubrication and hydraulic power systems of the in-pile loop. Cal- culated doses of 107 r were obtained. The specific gravity of the oil samples increased about 1%, and the viscosity increased about 60 to 90%. In a few of the samples a small amount of suspended par- ticulate material was observed but not identified. The radiation damage observed in these tests is not considered to be seriously defrimentql DEVELOPMENT AND OPERATION OF FORCED- CIRCULATION CORROSION AND MASS TRANSFER TESTS Ww. B. McDonaId Alrcrcft Reactor Engineering Division Operahon of Fused-Sult—lnconel Loops C. P Coughlen P. G. Smn‘h' A:rcraff Reac_tqr Engineering Division | R. A. Dreisbach : ~ Pratt & Whltney Aerl’Gf‘l‘ Twenty two fused- sait—lnconel loops were oper- ated durmg this quarter. A summary of the con- dn‘nons of operation of these loops is given in - _,Toble 2.1. The results of metallurgical examina- '_'hons of these Ioops are presented in Sec. 5, o “Corrosmn Research S The mu|or cause of failure of these fused-salt .Ioops has been the freezeup of fhe sclf in fhei coolmg conl when flow was mferrupted for any reason. " Most flow m’rerrupnons resuH from loss of power, either at the test rig or in the building as a whole. The freezing of the cooling coils has occurred in times as short as 30 sec. Preliminary tests have shown that a gas flame automatically 1gnn‘ed at the time of an interruption of the coolmg air will prevent freezmg for perlods of 5 min or more. Several methods of automatic |gmhon of such a flome were tried, but the only one which appears to give the surety of lgmhon requared is a high-resistance heater coil in the gas stream; the coil is energized from a 12-v, wet-cell circuit. -Liquid Metals in Multimetal Loops C. P. Coughlen A:rcrcff Reocfor Engmeermg Dwns;on R. A. Dreisbach Pratt & Whitney Aircraft Nme forced-circulation loops were operated with sodium in Inconel and in stainless steel tubing. A summary of the conditions of operation of these loops is given in Table 2.2, The loops were heated with electric heaters, and each loop had an economizer section. The results of metal- lurgical examination of these loops are presented in Sec. 5, ‘‘Corrosion Research.” A new test loop has been designed with which it will be possible to obtain accurate information on the oxygen content of sodium during operation. The test system, as indicated in Fig. 2.1, consists of a main loop, which includes the sodium-sampling device and a bypass cold trap, and a plugging- indicator loop, with its separate pump and flow- meter, (The plug indicator is described in a sub- sequent portion of this section,) The cooling rate of the entire loop can be controlled to a fraction of a degree per minute. The oxygen content of the sodium circulating in the main loop is controlied by use of the bypass cold trap. The plugging- indicator loop and the sampling device are both 7 used to :ndependenfly defermme the oxygen content " and thus to determine the effic:ency of ’rhe cold' B trap. In order to use the pluggmg-lndlcator loop, them valve between that loop and the main loop is opened, and sodium is allowed to flow from the main loop until the plugging- mdlcofor loop is filled to a predetermined level in the surge fank. 4 P S -l oW TABLE 2.1. SUMMARY OF OPERATING CONDITIONS FOR 22 FUSED-SALT—INCONEL FORCED-CIRCULATION CORROSION AND MASS TRANSFER TESTS Maximum Maximum . Loop Method of Type of Reynclds Te?mperah..lre Recorded Fyel Recorded Tube Fused Salt Ope-ratmg o No. Heating Heufed Number Differential Temperature Wall Tempera- Circulated Time Reason for Termination Section {°F) (°F) ture (°F) (hr) 4950-2 Direct resistance Straight 5,000 200 1500 1565 NaF-Z rF4-UF4“ 1000 Scheduled 4950-3 . Direct resistance Straight 10,000 200 1500 1690 NoF»Zer-UFAb 1000 Scheduled 4950-4 Direct resistance Straight 10,000 100 1500 1600 NaF-ZrF ,-UF ;% 1000 Scheduled 4950-5° Direct resistance Straight 10,000 200 1500 1575 NaF-ZrF ,-UF 1000 Scheduled . 4950-6. - Direct Resistance Straight ~8,000 300 1500 1620 NaF-ZrF -UF,# 1000 Scheduled 7425-1 - Direct resistance ' Straight ~10,000 200 1500 1600 NaF-ZrF ,-UF ¢ 22 Lecked at 22 hr; motor . failure 7425.1A - Direct resistance Straight ~ 10,000 200 1500 1600 NaF-ZrF ,-UF ,“ 1000 Scheduled 74252 . Direct resistance Straight 10,000 200 1500 1575 NaF-KF-LiF® 550 Fuel evalyation test; pump ‘ shaft seized at 550 hr 74253 Direct resistance ; Straight ~23,500 125 1525 1600 NaF-ZrF ,-UF @ 73 Motor overloaded; loop o g failed at 73 hr 7425-3A - Direct resistance ‘?,ti‘?VS?raight ~ 16,000 125 1525 1600 NaF-ZrF -UF @ 1000 Scheduled 742544 . Direct resistanceff“ Straight 10,000 200 1500 1575 NaF-KF.-LiF¢ 1000 Scheduled; fuel evaluation 4695-4D ;. Direct resistance : i Straight ¢ 10,000 200 1500 1595 NaF-ZrF -UF ,“ 20 Failed during power o ’ ' B . failure at 20 hr 0 4_695-4D-2i-‘,'Direcf.;resis'rance :;’:‘:‘.“Struig‘ht 10,000 200 1500 1635 NaF-ZrF ,-UF 4 500 Scheduled -‘4695-5(:-2};‘ Direct resistance;_fii Straight ~ 10,000 200 1500 1635 NaF-ZrF ,-UF @ 1000 Scheduled " . 742541 [ Direct resistance;:’ Straight . 2,750 200 1650 1700 NaF-ZeF -UF ¢ 1000 Scheduled 49353 . Gas i Coiled = 1,000 100 1500 1540 NaF-ZrF -UF,* 1000 Scheduled D 49354 . Gas Coiled 10,000 100 1500 1690 NaF-ZrF -UF % 486 Clutch failure caused : T freezeup; failed on “ . re start m 4935.5 - Gas " Coiled 10,000 206 1500 1550 NaF-ZrF ,-UF ,* 682 Clutch failure caused E .. .\. freezeup; failed on 8 . restart m " 49357 ¢ - Gas . Coiled 6,000 200 1500 1700 NaF-ZrF -UF % 330 Power failure caused z ' freezeup; failed on E o . restart =z o " 4935-7B . Gas "Coiled 6,000 200 1500 1700 NaF-ZrF ,-UF % InTest Conditions noted were o ' ‘ ' new conditiens im- m pressed at 600 hr; o s scheduled for 1000 hr "“l 49358 Gas - Coiled 6,000 200 1500 1700 NaF-ZeF UF,« 435 Terminated at 435 hr by > : thermocouple burnout o 4935.9 " Gas “ Coiled 4,000 200 1500 1800 NaF-ZrF ,-UF ,* 1000 Scheduled ;‘ 4 Composition: 50-46+4 male %. o bComposifion: 50-46-4 mote % with 2 wt % of the total uranium converted to U . — w0 €Composition: 11.7-5¢.1-29.2 mole %. o O th | ;ANP PR’OJE‘CT P‘R'oc'REss R’E'P'O"R‘T'z TABLE 2, 2 SUMMARY OF OPERATING CONDITIONS FOR LOOPS THAT CIRCULATED SODIUM TemPemel’e T Maximem T Operatmg-: ' Material of ' Cold Réynolds Differential Recorded Fluid Condition of Time | LoopNo T Cornstrdction Trap Number CF) Temperature (°F) Sodium (hr) 49514 dnconel No | 55000 30 1300 Commercialgrade 1000 49515 ncomel Ne 59,000 300 1500 0.15% ox:de added”’“:" | 49516 dnconel Yes 59,000 300 1500 Highpurty 500 '49‘51,"-7_’:"""Typ3316 © Ne 59,000 300 1500 Commercial grade ~ 475% stainless steel 7 _ ’ 7 e 49518 lnconel Yes 59,000 30 1s00 Commercial grade T 1000 4951.9 _‘lnconelf ~ No ~59,000 300 1500 “1% bquum added S s00 - 7426-] ‘:ihtlncone[ A Yes "\’59,000 o 30'6 S ‘]500; g banum added o ]000 c o B 7426;2“ ‘__;Z_Incone[ -_ N - No ~59,000 300 1500 0.05% oxide udded 1000 - - *Operahon termmafed by a power faliure. ' e o S E 7 UNGLASSIFIED o R ORNL-LR-DWG 2046 . a SURGE TANK SURGE TANK PLUGGING INDICATOR LOOP , vk s FLOWMETER LOCATION b E.M. PUMP (ot € W\ Y PLUGGING DISK -y it ({ o MAIN LOOP SODIUM-ANALYZING AND -SAMPLING DEVICE SUMP TANK ) COLD TRAP E ) F|g.2'l Loop for C:rculatlng Sodium in Inconel or in Stcunless Steel Tubing to Study thethfect of ;:f?r fhe Oxule Confenf of fhe Sodium. ) £. M. PUMP 4o - sy ‘The valve is then closed, and the sodium is cir- culated by the electromagnetic pump in the un- heated plugging-indicator loop. The plugging disk collects the oxides precipitated as the tempera- ture of the sodium decreases, and it eventually plugs. The temperature at which pluggingoccurs is compared with a calibration chart to determine the oxide content of the sodium. The plugging- indicator loop is then heated until flow is re- " established. The valve is then reopened and the sodium is forced, by pressure, back into the main loop. PERIOD ENDING SEPTEMBER 10, 1955 ‘The data on oxygen content obtained with the plugging-indicator loop are compared with those obtained with the analyzing device attached to the main loop and with results of chemical analyses of samples removed from the main loop. The analyzing device attached to the main loop is described in Sec. 9, ‘“‘Analytical Chemistry of Reactor Materials.”’ A loop in which NaK is to be circulated has been designed with the same surface-to-volume ratio as that of the primary NaK circuits in the ART. A sketch of this loop is shown in Fig. 2.2. UNCL ASSIFIED ORNL-~LR—-DWG 9047 Fig. 2.2. Loop for Studying Mass Trunsfer in an lhconél’l.dbp Circulating NaK. 41 R T T T T T, T T T e R e e A TR R TR R R R TR T - T T TR a e L S el ANP PROJECT PROGRESS REPORT It is desigried to operate at a maximum NaK tem- peraiure of 1600°F and a minimum NaK temperature . ‘"':PUMP DEVELOPMENT " E.R. Dytko . Pratf & Whn‘ney Aircraft Mechamcal Shakedown and Beurmg-and-Seal Tests .' "A ‘G. Grindell _ _*::Asrcraff Reuctor Engmeermg D|V|5|on _ The ART-'rype MF-2 pump lncorporates two fuce-A : '*type mechamca! seals, The seal specifications . requu'e the upper seal to have a leakage rate of - oil to the ctmosphere of not more than 20 cm3 per 24 hr at 70 psi. The lower unit is to have a leakage o of onl ln'ro helium across a pressure differential of -0 to 5 psi of not more than 2 cm3 per 24 hr. The ""i'-‘,fi'_f‘i""‘seoled fluid is a light, spindle oil having a vis- cosity of 6'0'“SSUA (Saybolt seconds universal) at ]00°F Most of the manufacturers com‘acfed would':__ not bnd on the seals, and the three or four com-' panies who did make bids would not gucram‘ee - their seals to meet the s'rrmgen'r reqmrements of ‘Therefore a ‘seal evaluation | ) program! was initiated in which a small number of seals from the Fulton Sylphon Dlv;slon, the Dura- _ '_'f'of ]QOOOF The Reynolds number is to be com- IR poroble to thct in prlmqry NcK circuits of the ART Sl L " the specifications, " Ine., will be tested. metallic Corporaflon, and the Koppers Company, that low leakage rates could probably not be achieved with metal-to-metal seals, and, conse- quently, the seals being tested are made of carbon products and ceramics, The evaluation of the Fulton Sylphon seals is nearly complete., Nine of the 11 tests started have been completed, and over 1600 hr of testing time has been accumulated. The conditions of the tests are given in Table 2.3, and the results ID. R. Ward, W. C. Tunnell,and J. W. Kingsley, ANP Quar, Prog. Rep. june 10, 1955, ORNL ]896 _p 33 _ TABLE 2.3. CONDITIONS OF TESTS OF MF-2 PUMP LOWER SEALS MANUFACTURED BY THE FULTON SYLPHON DIVISION Oil temperature: 200°F Shaft speed: 3000 rpm Test Material Flatness? (bands) Rcmo of Preload Pressure Bearmgb Jownal Radius No. Seal Nose Wear Ring Seal Nose Wear Ring (lpy Differential \ 4 (p) to Radial (psi) Clearance 1€ Sabeco 99 Ketos® 2 12 50 0.5 040300 800 2€ Graphitar 14 Ketos 6 3 30 0.5 0 to 300 900 3¢ Sabeco9 Ketos 8 3 30 0.5 010300 1250 4/ Sabeco 9 Case-hardened steel 4 4 50 0.5 5/ Sabeco 9 Ketos 2 50 0.5 6/ Sabeco 9 Case-hardened steel 3 1.5 20 1310 16 7/ Sabeco 9 Ketos 3 3 20 0.5 | 8¢ Graphitar 14 Case-hardened steel 4 3 20 0.5 0to200 810 12/ Graphitar 14 Ketos 8 6 20 0.5 o 6A Sabeco 9 Case-hardened steel 3 1.5 20 0.5t07.5 6 6 20 0.5 7Af \ __vVS'\ql\?Aeco‘ 9 7 Ketos Meoeeiec-l‘ WI?.]"I Eehdm light; one band equivalent to 11.6 uin. ‘bBearmgs made of ASTM-B-144-49-36 bearing bronze. ' CTesfs made in beurlng and seal testing facility. ., ‘dSabecO 9i isa feaded bronze | - eKettbs is an 18-4-] type of tool steel. - ,,_fT_esf made m_cold shakedown facility; ne bearing loads applied. Earlier tests had mdlcafed* ' o . b 24 - K % i are presented as Fig. 2.3, It may be noted that the low specified leakage rate has not been met, and only four seals had rates lower than 1 em3/hr. It was noted that the Fulton Sylphon seal was not balanced, and the resulting pressure changes caused variable performance of the seal, Repro- ducibility of results from seal to seal has not been possible. In similar tests the operation of the upper seal was satisfactory, with leakage rates of less than the specified 20 cm3 per 24 hr being attained in six tests. PERIOD ENDING SEPTEMBER 10, 1955 The lower journal bearing of the pump was de- signed initially to carry loads of up to 600 b, but hydraulic studies revealed that the expected bearing load would be 150 ib or less.. With the lower loads it appears to be feasible to employ Inconel as the journal material and to thus obviate the need for a hardened journal bushing, Tests 1, 2, 3, and 8 were conducted in the bearing and seal testing facility, and loads up to 300 Ib were satis- factorily carried by the Inconel shaft in a bronze bearing. UNCLASSIFIED ORNL-LR~DWG 9048 700 TEST No. TEST No. TEST No. . ) 600 : : 7 TEST No. TEST No. 500 TEST No. TEST No. TEST No OO N oG ph 74 .42 A TEST No. { >

@ —] 400 — / 300 * ACCUMULATED SEAL LEAKAGE {cm®) - Frirlg. 2.3, Results of Leak&ge Tests of the MF-2 Fuel P"u'mp Lower Seal, 43 i G ANP PROJECT PROGRESS REPORT Short-Clrcmi Pump-Test Si'cmd ' | 5 M. DeCamp, Je. A;rcrafi Reactor Engmeerlng DW|S|on ' ~J.B. Kerchevcl Prcn‘t & Whlfney Aircraft Fobrrcahon cnd ossembly of the Ffirst short- ‘,__cnrcun' pump-fest ‘stand, described prewously, have been essem‘:ally complefed ‘and water tests have been started, These water tests are for _ "_checkmg mechumcal ‘fits and interferences, check- ~ “ing pressure breakdown bypass flow rates, and '"'correlahng head and flow data from this loop with those obtained on the water test stand.’ ' Assembly of the pump and the volute indicated” - _rhcn‘ the radial seals with metallic O-rings were o uTvety sensmve d!menswna”y. A 0002-|n. intet- '“"‘f'i’":fference on a 6-in.-dia O-ring was not enough to o seal, while a 0008- to 0.010«in. interference ~ caused difficulty in assembly and disassembly. Data were taken on bypass flow rates to deter- mine the effect of the left-hand threads used in the flow breakdown annulus. With a radial clear- ance of 10 mils and thread depth of 37 mils, a by- pass flow rate of 2.3 gpm was measured at a pump speed of 2700 rpm; the main circuit flow rate was approximately 630 gpm. Increasing the radial clearance to 15 mils gave the desired flow rate of 4,77 gpm. The data obtained in the water tests will be use- ful in analyzing the data obtained at high tempera- tures, since it will be difficult to measure dis- charge pressures when the system is operating at high temperature. Throttling orifices for the loop were calculated to give a 50-ft head at 650 gpm. Data obtained in the water tests indicate a flow rate of 650 gpm at a 46-ft head. The test loop is now being readied for operation at the design tem- perature, 1400°F, High-Temperature Pump-Performance-Test Stand R. Cumry H. Young | Pratt & Whitney Aircraft The design layouts have been completed for two loops for testing MF-2 ART-type pumps at tem- peratures up to 1400°F, Callbrcn‘ton, shakedown, cmd endurance tesfs on MF 2 pump rotary assem- 25, M. DeCcmp, ANP Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 35. 3G. D. Whitman, R. L. Brewster, and M. E. Lackey, 7 -"‘;ANP Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 32. .:b-lies wnli Be: made wnth NaK or sodwmand wa'rh “the fuel mixture NaF-ZrF4-UF4 (50-46-4 mole %) as the circulated fluids. Data obtained at 1200 and 1400°F on shaft speed, head, flow rate, and power input will be compared with water-perform. ance data, and cavitation and vibration characteris- tics will be noted. An endurance test will then be run at design head and flow rate, The xenon- removal system, inCIuding the helium-bleed and o:l !eakage-removal sysfems, is to be incorporated in the circuit for checking in conjunction with the main fluid circuit. One of the two test stands will be available for acceptance testing of the final __MF-2 rotary assemblies with NaK., A concentric p[pe des:gn was chosen for the test stand loop to eliminate thermal stresses from nonuniform heating or cooling, to reduce the num- bet of critical welds, und to provide a compact assembly, The compactnessof the cssembly makes possible a low fuel inventory. A conventional venturi is located 15 pipe diam- eters (60 in.) downstream from the pump volute discharge, and a piston-type throttle valve is located downstream of the venturi. The valve travel was specified within the recommended travel of a suitable bellows used as the valve-stem seal. This valve cannot be fully closed; therefore, as presently conceived, the minimum loop resistance, with the valve wide open, will permit testing at about one-half the rated pump head with rated flow, and the maximum loop resistance, with the valve closed, will permit testing at approximately one- half the rated flow with the pump delivering the rated head. A screen-type, axial-baffle, flow=control device is provided just below the inlet to the impeller to prevent an uneven velocity profile and prerotation in the stream entering the pump. To simulate the fluid-expansion and xenon-removal region, a sepa- rate chamber is provided above the top plate of the pump volute. Fluid enters and leaves this chamber only through the pump barrel wall, and this cham- ber is not directly connected to the pump inlet " chamber except through the impeller. The rise in level of the fluid in this chamber for a 100°F in- crease in the temperature of the fuel mixture will be about the same as that for the ART. During steady-state high-temperature operation, the pumping power will be removed by blowing a high-volume low-pressure air siream transversely across the outer loop pipe. A power failure will - e T T T T Y I o T PERIOD ENDING SEPTEMBER 10, 1955 cause automatic cutoff of the cooling air, and it is tent in the NaK was measured by means of a plug anticipated that the fuel can be dumped before it indicator and by chemical analyses of samples freezes in any section of the loop. taken from the pump bowl, The plug indicator is a - o _ concentric pipe stem connected to the NaK circuit, HEAT EXCHANGER TESTS with a filter containing five 0.030-in.-dia holes E. R. Dytko located at the bottom of the inner pipe, which plugs Pratt & Whitney Aircraft with precipitated oxide at the saturationtempera- R; E. MacPherson ture of the oxide in the NaK., Both the plug indi- cator and the chemical analyses showed that the Aircraft Reactor Engineering Division _ L . cold trap had reduced the initial oxide content of | lntermefliaié Heat Ethangér Tests 1000 ppm to values of 150 and 650 ppm, respec- R. D. Peak H. M. Coopér: L. R. Enstice ?ivelhy, ofs found .by the two me:fhods after .'rhe fi‘rsf Prat’r&Whltney Aircraft 56 hr o operaTmn. This discrepancy in oxide content, as obtained by the two methods, cannot be The new experlmentul assembly (sfond A) for explained at this time. intermediate heat exchanger fests, described The second cold trap test was of 193-hr duration previously, is shown in Fig. 2.4. This apparatus (the period from 373 to 566 hr of operation) with was operated for 690 hr in a series of furnace and NaK flow rates of 50 to 110 gpm and NaK tempera- diffusion cold trap tests of the NaK system and @ tyres ranging from 1000 to 1400°F; the tempera- 2-hr cleaning cycle of the fluoride-fuel circuit. A tyres in the cold trap were below 750°F. In this chronological description of the tests that were test, only the plug indicator was used to measure is given in Table 2.4, that the oxide content was reduced from an initial As stated in Table 2.4, the 1-Mev gas-fired fur- 1000 pom 1o 150 ppm after the first 168 hr of NaK nace (Struthers Wells Corp. ) for heating the NaK, as circulation, This level of oxide content is con- installed, did not give satisfactory performance. sidered to be too high for a NaK-Inconel system. The best over-all thermal efficiency that could be One tube bundle of the fuel-to-NaK intermediate obtained was 28%, with 1.7 x 10® Btu/hr being heqt exchanger (No. 2), described previously, transferred to the NaK. In an effort to improve the geveloped o leak after approximately 350 hr of performance, a 12-ft-high stack extension was gperation of the NaK circuit, The fuel had been placed on top of the original 4-ft-high stack. As a circylated for only 2 hr in the fuel circuit during result, a thermal efficiency of 31% was obtained, this period. At the time that the leak occurred, with 2.83 x 108 Btu/hr being transferred to the the fuel circuit was empty, except for small un- NaK. Since the heaf transfer was still below the drainable portions in the pressure transmitters, fuel design requirement, a new, larger burner was then __pump, and the lower ends of the heat exchanger installed, Wthh proved to be capable Of t"‘Z’V‘s't,_‘:_m‘ube bundles, With a pressure differential of 35 ferrlng 3.85 % 106 Btu/hr (] 13 MW) to the NaK ... psi across the NaK and fuel circuits, a consider- '7 Wh'te bU"“'“Q 8400 ‘scfm Of:NU’fUW‘ 905; ‘the thermar able wquanhty of NaK flowed ln'ro the fuel circuit efflmency wn‘h th“ er was 487 wnhi i"e'__ the leak was detected, The leak was de- _‘-',.';',_j:._furnace mief Aqnd exit jemperaf;lres of ]307 an&; ‘ fi_“"tectédflwhen the Iower spark plug in the fuel pump 1600°F and’ aN rate of 140 gpm, o “shorfed . ‘Sbbsequent dumping of the NaK circuit Two tests were ¢o dUC’fed fO evaluate the func- ‘_resulted in contamination of the NaK circuit and -_'”°“ of the diff‘p_slon C°|d "C’P (0 cylmdrlcal C°"'.“_ the NaK dump tank with some of the fuel which o tainer, W”h a»yo!ume 17 of that of the NaK circuit, could not be completely drained following the 2-hr ”i',connected to the main circuit by a pipe 2 in. in operation of the fuel circuit. “Q_fh) in removing sodlumm;w._" The fuel-to-NaK heat exchanger was removed first, or prehmmary test, from the assemb[y and exammed Pressure tests and a NaK temperature of 1500°F. The oxide con- “ 4R, D. Peak, ANP Quar, Prog. Rep. June 10, 1955, 5P, Patriarca et al., ANP Quar. Prog. Rep. June 10, ORNL-1896, p 37. 1955, ORNL-1896, p 131. 45 (Thé} Pe”Od from 50 to 219 h" showed that only one tube in one of the two 100- - _°f °Pe"°'“°") W”h NaK flow rates of 55 10 85gpm tube bundles leaked. The leak was found to be a o s ANP PROJECT PROGRESS REPORT TABLE 2.4, SUMMARY OF INTERMEDIATE HEAT EXCHANGER TESTS : Hours of : , L Remarks : ¥ Operation _ i 0 B - Fllled system wnth NaK (56% Na-44% K) at room femperature. o 0to 16 7 . "'Nal( system elecfncally heated to 300°F NuK flow rai'e, 100 gpm, hlghesf NaK tem- ‘ ' perature oh‘mnable wnfh electric heufers found to be 300°F. | 16 to 50 NuK system operated mfermuflenfly at various flow rcn‘es cnd femperutures ‘to check ' opercblllfy of 1-Mw gas -fired furnace; furnace found to be unsqhsfoctory, ‘thermal ' efflclency, 28%, heat transferred fo NaK, 1.7 % 108 Bfu/l'lr. NqK pump had to be replccecl at end ‘of 50 hr of operahon beccwse of fmlure of the onl-fo-helnum seal 50 to 219 ~ NaK system operoted |sotl1ermc|lly at lSOOoF wnfl’l NaK flow rafes of 55 to 85 gpm to o E : - check operahon of diffusion cold trap, cold trap reduced oxygen content of NaK' from $ - 1000 to 150 ppm, accordmg to plug indicator, or 650 ppm occordlng to chemical ana Iy- Csis. NaK replaced wnh new supply because of high oxygen confenf NaK pump agcnn ' 'replaced at end of 219 hr of operahon becouse of beormg fcnlure 75t0 77 | Fuel circuit filled for cleamng wflh NaF ZrF UF (50 464 mole %) and Operated | - lsofhermolly at lSOOOF for 2 hr at a fuel flcw rate of 60 gpm; fuel then dumped. 219 to 354 NaK system operafecl |m‘erm|flenfly at various flow rates and fempercn‘ures to check gas-fired furnace; furnace found to be satisfactory after alterations; thermal efficiency, 48%; heat fronsfer to NaK, 3.85 X 106 B'l'u/hr {1.13 Mw). 354 Blower started with NaK c:rcuuf |sofhermal at 95°F fo check rud:utor air flow. 354 to 358 NaK system operated lso’rhermolly at 'l400°F at various NaK flow rates fo check pressure drop in system., Test terminated because of a leak in the heat exchanger. Heat exchanger removed for examination and fuel pump removed for cleaning. NaK piping installed to feplace heat exchanger. 358 to 373 NaK circulated at 100 gpm with system isothermal at 1400°F for cleaning circuit; NaK drained while hot; NaK replaced because it was found to be contaminated with fuel. 373 to 566 NaK system operated isothermally at 1000 to 1400°F ot various NaK flow rates to check effectiveness of diffusion cold trap; cold trap reduced oxygen conten'r from En 1100 to 150 ppm, as determined by plug IndlCO‘l’Ol‘ 566 to 621 Blower started to create temperature dtfferenhql of 200 to 2500F across NaK-to-orr radiator; Nak sysl’em ‘operated at various NaK flow rates and NaK temperatures of 11000 to 1250°F Radiator gradually plugged with fuel contaminants. Plug mdlcator _showecl oxygen confem to be too low to cause plugging. Test terminated because of a leak in fhe radiator. Radlofor removed for exammahon. Cold trap, plug lndlcofor, ""‘_'.cnd Nal‘( sump removed for clennmg. 621 to 690 o _ " NaK system bemg cleaned radial crack on the |n5|de of the tube bend. The was flcwing-'fhreugh fhe tubes at a .:cliffe‘re‘rllifeln-' 100-tube bundle and header that leaked is shown perature than that of the heat exchanger shell. before and after operation with NaK for 358 hr in Figs. 2.5 and 2.6. The tube that leaked is indi- cated in Fig. 2.6. The tube distortion shown in Fig. 2.6 was caused by fhe thermal cycling that occurred when NaK 46 There were 73 instances in which this tempera- ture difference ranged from 200 to 1000°F, Since no fatigue cracks were found in the 36 tubes that could be visually inspected, it is thought that the one tube that failed must have had a flaw that . {rihe, Mpu . gullEk. il G L e R - ' -"n o B oom - ; - . - . . LAk - . - o ", L : Sam . : Lol e : « D, i ~‘,= ‘ L pske D 0 . s L i ~ .4“‘4 s . s 2 Ly §S61 ‘0L ¥39WILdJ3S ONIAONI QOl¥3d ' made it susceptible to stress failure, After the heat exchanger had been removed and replaced with piping, operahon of the NGK system was resumed. The NaK was circulated for 15 hr at 1500°F and then drained while hot, Since the NaK contained fuel contamination, it was rep[aced with fresh NaK, and the second cold trap test de- scribed above was made. However, the operation radiators, described prevnously,6 developed a leak. During the last 55 hr of operation, a “steady in- crease in the NaK pressure drop across the radiators was noted, The pressure drop increase coincided with startup of the radiator blowérs, which caused the radiators., The increase in pressure drop, along with a gradual decrease in NaK flow at a constant pump speed, could only mean that some of the r_adlc’ror tubes were pluggmg. These plugged gl tubes were cooled by the air flow from the blower, with the result that there were low-temperature regions in the otherwise high-temperature radiator Fig. 2.5, The 100-Tube Bundle and Header of ..Intermed:ate Heat Exchanger No. 2 Which Leuked"' After 358 hr of Operation with NaK Circulating in the Tubes. | S1bid., p 134. had to be stopped again when one of the NaK-to-air a NaK temperature differential of 200°F _across “ matrix. The high thermal stresses thus created were probably of significance in the ultimate failure of the one radiator unit, The radiator that failed is shown in Fig. 2,7. The fuel that leaked into the NaK circuit after the heat exchanger failure was not flushed out during the 15-hr period of circulation of the NaK after the removal of the heat exchanger. The analysis of the black material scraped from the fins of the NaK-to-air radiator when it was being examined after the leak occurred showed 34% zirconium and 0.25% uranium; the remainder of the . 'material was sodium, potassium, iron, nickel, chromium, and copper. The NaK circuit was cleaned by the Materials Chemistry Division. A total of 4.2 g of zirconium, 0.46 g of uranium, and 3939 g (8.6 |b) of Inconel ‘was removed in the cleaning operation. Two 5% nitric acid washes removed 87% of the uranium, and one wash with 2% ammonium bifluoride and 2.5% nitric acid, a highly corrosive agent, removed 82% of the zirconium, 'qu ammonium bifluoride and nitric acid washes removed 90% of the Inconel. PERIOD ENDING SEPTEMBER 10, 1955 The Inconel removed by the cleaning process reflects corrosive attack to a depth of 1.5 mils on the inside walls of the Inconel piping throughout the NaK system, if it is assumed that the attack was uniform, Test stand A is currently being rebuilt. Radiator units made by the York Corp. and heat exchanger bundles made by Black, Sivalls & Bryson, Inc. are being used. Test stand B, which is almost identi- cal to stand A, is now 70% complete. It will be used to test two radiator units (500-kw size) built by Pratt & Whitney Aircraft and two heat exchanger bundles made by the Metallurgy Division of ORNL., Test stand C, another stand identical to stand A, is now 10% complete. Small Heat Exchanger Tests J. C. Amos Aircraft Reactor Engineering Division L. H. Devlin J. S. Turner | Pratt & Whitney Aircraft The first of a series of tests of small fuel-to- NaK heat exchangers was terminated on June 29, UNCL ASSIFIED Y- 16065 Fig. 2.7. NaK-to-Air Radiator Unit from Intermediate Heat Exchanger Test Stand A After NaK Leak and Fire. The side cover has been cut away. 49 TE TR S R St R B ekl i o ~ ANP PROJECT PROGRESS REPORT .]955, dffer:-"Séo hr of opercfiofi. | The test as- sembly, which was described previously, along ‘with a presentation of the preliminary results,” has o been dismantled, and the components are curren'rly o bemg sub|ecfed tometallurgical inspection. A sum- ) mary ‘of the cpprOXImofe operating conditions is ~given in Table 2,5, The heat transfer data obtained _are presented in Fig. 2.8 and are compared w'ifh'the' ~résults from the theoretical relationship Nu/Pr0+4 = . 0.023 Re® 8, with data obtained for a 100-tube 'jhecn‘ exchanger ‘operated with water,® and with a ' *curve showmg the data for the 20-tube heat ex- ' chcmger ad[usted for a IOO-tube heat exchonger 7'J C Amos, M. M. Yarosh, and R. I. Gray, ANP Quar. . Prog. Rep. June 10, 1955, ORNL 1896, p 37. 8). L. Wantland, ANP Quar. Prog. Rep. June 10, 1955, ' '.*’,,_':ORNL 1396, P 149 The equivalent diameter used in calculating the Reynolds number was based on the total wetted perimeter of the tubes plus the side-wall area. The fuel-side pressure-drop data obtained are com- pared in "Fig. 2.9 with a theoretical pressure-drop curve calculated from data obtained from water ’resfs carried out on similar tube bundles ’ro deter— " mine the pressure drop created by the spacers. The calculated pressure drops are higher than those that would be predicted by fheory because of the presence of spacers. During the last 456 hr of operahon of fhls test the NaK inlet and outlet temperatures were main- " tained at approximately ART design conditions to study mass-transfer effects. No appreciable amount of mass transfer was detected by visuval inspection when the Ioop was dismanfled. During | TABLE 2.5, SUMMARY OF SMALL HEAT EXCHANGER OPERATING CONDITIONS”-J?' B Hours Fuel NaK NaK Mean Fuel Fuel Mean Fuel . of Reynelds Temperature AT Reynolds Temperature AT O peration Number (°F) (°F) Number (°F) °F Remarks 7% 1300-5500 1300 15 45,000 (min) 1300 30 Pressure drop data 184,000 (max) being obtained 2%% 1000-6500 1400 15 26,000 (min) 1400 30 Pressure drop data 187,000 (max) being obtained 444 1400-5500 1350 97 (min) 74,000 {min) 1225 (av) 142 (min) Héat transfer data : ' 200 (max) 206,000 (max) 200 (max) being obtained 272 500-6400 1350 90 (min) 40,000 (min) 1225 (av) 126 (min) Heat transfer data 228 {max) 290,000 (max) 240 (max) Being obtained 256 2850 1350 135 160,000 1275 130 Endurance run 472 3500 1450 115 145,000 1400 135 CEndurance run 168 3400 1360 20 135,000 1350 35 Thennalcychng | | e L. test 16 600 1300 272 40,000 1225 290 ; Thennalcychng 6% 600 1325 280 40,000 1240 380 Thermal cychng 456 4000 1455 100 40,000 1250 490 .'Massfrunsferdata - 1557f' bemg obfo:ned INaK with fhe c0mp051t|on 22% Na-78% K used for the first three runs; NaK with the composfluon 56% Nq-44% K o used for all other runs; fuel mixture for all runs was NaF-ZrF -U F (50+46-4 mole %). Thermcd cycling discontinued after two complete cycles, . c'-Buh,rl ‘alcohol circulated in NaK Loop for 19 hr after termination of test, .Nu/ProA\‘:.’::;; i e \ ’ & : -t U[;‘_L;‘;P_RESS"URE‘{: DRQE’,‘;-ACROSSESHEAfi EXCHANGER - (psig) S A e e “ ORNL-LR~DWG 9049 30 T T - & DATA TAKEN DURING L - [ INITIAL OPERATION” ' 1A 1 G DATA TAKEN AFTER S 7 [T 500 hr OF GPERATION ° i ' ® DATA TAKEN AFTER - A 4A L 4000 hr OF OPERATION” v // 20 L -i 1 ,7 ’l - A. R o4 _ 0.8 Nu/Pr% = 0.023 Re‘. —a/ Ve io. 1 / 7| - ¥ o v -/ / : 5 ‘ ) X WATER DATA FOR L .| 100-TUBE HEAT EXCHANGER ™~ | {™20-TUBE HEAT EXCHANGER DATA ADJUSTED FOR 100 TUBES 10,000 - Flg. 8 Heat Transfer ‘Dutq for 20;T‘ube Fuel; to-NuK Heat Exchunger. ) ORNL-LR-DWG 9050 R N — & | A DATA TAKEN DURING 7 | INITIAL OPERATION ' o/ | O DATA TAKEN AFTER Y 500 hr OF CPERATION 9 / 50 |—® DATA TAKEN AFTER iy 1000 fr OF OPERATION o Fig‘. 2.9. Fuel-Side Pressure Drop Data for 20 Tube Fuel fo-NaK Heat Exchanger. PERIOD ENDING SEPTEMBER 10, 1955 this period of operation the efficiency of the NaK- to-air radiator used as a heat dump dropped con- tinuously for approximately 360 hr and then im- proved suddenly. Samples taken from the NaK sump tank at the completion of the test indicated a very high oxygen content in the NaK (approxi- mately 2500 ppm). A circulating cold trap has been designed and will be installed on future test assemblies in an effort to remove oxides from the NaK. Assembly of two, new, small heat exchanger test stands is opproximately 25% complete. Each of these stands has a 500-kw electric heat source and will be used to test six 20.tube heat ex- changers, Two heat exchangers are being fabri- cated by ORNL and four have been ordered from outside vendors. A 25-tube heat exchanger is being designed, with ART tube sizes and spacing, that will be operated at ART design temperature and flow conditions. [t is proposed to procure five of these units from outside vendors. A block diagram of the design operating conditions for this group of heat exchanger tests is presented in Fig. 2.10. STRUCTURAL TESTS E. R. Dytko Pratt & Whitney Aircraft G. D. Whitman Aircraft Reactor Engineering Division Outer Core Shell Thermal Stability Test D. W. Beli th‘ & Whn‘ney Aircraft A one-fourth scale model of the Iower half of the 2]-m. recctor core shell was fabrlccn‘ed for tesfs of fhermal “and’ s’rructural Sfdblllfyr when sub;ected to cyclic themal stresses at reactor operahng conditions. The model, shown in Fig. 2.11, was muchmed from Inconel bar stock and "/__‘/_\gvd‘sfi__r_'jxsjl"_g_‘VS'"elleved before the_ flncl mochmlng Wi ‘e helcl to 40.005 in, ’the dlcmeter cncl +0 003 in.on the thickness. The - same ]ength-to-dmmefer ‘and” fhickness-to- ’7 those of the fU“ srze _ 7 e"full-sne core she“ durmg reactor operation. “An ]nconel housmg is being fabricated that will form a /10"”' annulus on both sides of the shell. 51 it A Co "ANP PROJECY PROGRESS REPORT 1 0 S sost” 1 - 400 kw _ A L 4 - 70° 4 - _ | NaK-To-AIR 1070°F 1 RADIATOR 25 pslg § APygk = T psi g 25 psig y & § . NaK 4 PUMP - : ’ 34 gpm A 144 psig 1 AT = 430°F i BPyox = 82 psi 4 1070°F ; FUEL-TO-NaK 4 psig ; - HEAT EXCHANGER : _ ¥F 1250°F 66 psig 25 psig 3 ATyg = 350°F g AP e = M psi 4 25 psi { psig ¥ ] FUEL - PUMP ~ 9.6 gpm 7 psig APeyg, = 5 psi 4600°F RESISTANCE 4 1250°F 66 psig HEATER T4 psig ‘400 kw Fig. 2.10. bes-tén'éonaitioee fet Test.s of 25. Tube Fuel-to-_qu_ Heat Exchanger. placed circumferentially every 60 deg. The large- diameter end of the shell will be welded to the housing, and the small-diameter end will be at- tached to a bellows so that there will be no stresses . on, ‘the sheli that are due to axml thermal expan- - sion. Sodlum er be used to 1mpose a rcdlal tempera- ‘:temperature ‘of the core ‘shell ot this point will ‘be between 1450 and 1500°F. ‘Sodium at 1550°F ‘will e enter the inner annulus at the smal! dtameter end and [euve at T300°F Sodlum at. 985°F will low counfercurrently in the outer onnulus and ‘eycled ‘between the above "conditions ‘and iso- ,-'therma]_operatton at 1200°F for 100 cycles, After - of Zhfii‘ -ART Reactor Core'_‘_Shefl Fabncutecl for ¥ The outer annulus will contain six axial spacers : ure dlfferenttu] of 300°F across “the core shell ‘at’ the small-dnameter end The msu!e surface' ' -“Iemfi/’e at 1065°F. The core shell will be thermally s test | has ‘been. completed, |t has been planned 'Fig. 2.12. Fabrication has ‘been “started on twc»;' ertain wBether the core shel! wnll buckle o Fig. 2.11. One-Fourth-Scale Model of Lower Half L E Tests of Thermal Stability. under an extemal sodium pressure if the fuel pumps should fail during reactor operation. The test stand used for the first small heat exchanger tests is being modified for these tests, Heating and cooling of the sodium will be accomp- lished with a 200-kw resistance heater and an' . ) i F 'ARE sodlum-to-cur rcdlctor. L J. C. Amos LA M&nn ' Aircraft Reactor Engineering Division C. H. Wells Pratt & Whitney Aircrafi A desagn has been c°mpieted of an “anvil bend- | :mg test’’ apparatus for obtaining basic mformatlon on the behavior of Inconel under strain cyclmcl at elevated temperatures in both lnert cmd corrow sive atmospheres. This opporotus is’ sflown of these units. Affer shakedown operation of o i PERIOD ENDING SEPTEMBER 10, 1955 . + 1. UNGLASSIFIED g CRNL-LR-DWG 9052 é - ' SPARK PLUG PH_OB_E FILL LINE THERMOCOUPLE THERMOCOUPLE . FITTING FITTING GAS CONNECTION » ch S1— RUBBER 0-RING, ,-in. 0D x ¥g-in. ID x 0.070-in. DIA. {5 REQUIRED) PEDESTAL-——__| kR - TOP FLANGE ASSEMBLY ] ,\TB\ r o ACTUATING ROD |-t / O-RING & L LIQUID LEVEL ALIGNMENT PL. / UPPIfR ANVIL\ /TEST SPECIMEN | | . LOWER ANVIL - .' | TANK * - L ' . : Fig. 2.12. Inconel Strain-Cycling Test Apparatus. 53 s e e ANP PROJECT PROGRESS REPORT these two units the design will be reviewed and revised, if necessary, and three additional units will be fobricated and placed in operation. Eachtest assembly will accommodate two Inconel sheet test specimens 2?8 X ]/4 X ]/8 in. Interchange- able anvils with radii of 12, 15, 20, and 31 in. will be used to prowde various strains, lt is plcnned fo run the first test in an atmos- o phere of heltum at 1200°F with 12-in.-radivs anvils . that will impose approximately 1% strain. One - specimen will be eycled on o 2-hr half cycle, and ' 'j\another will be cycled on a }’-hr half eycle, The ~purpose of this test will be to obtc:m an indication Vof the reloflve relcxchon times. B Dufc w:“ be ob’ramed on per cent of strain, . length of cyc[e, number of cycles to fracture, - effect of temperature, and effect of surrounding '-'medxum {for example air, helium, sodium, NaK, fuel). As the tests progress, the specific combi- nations of conditions to be studied further will be evaluated. Thermal«Cycling Test of Sodium=Inconel- Beryllium System M. H. Cooper R. D. Pedk Pratt & Whitney Aircraft The third test to be operated in the sodium- beryllium-Inconel compatibility testing apparatus, described previously,” was started on July 14, 1955. The test section consists of a beryllium cylinder drilled centrally with a };‘-in.-dia hole through which sodium can flow. The loop was operated isothermally at 1100°F for 100 hr, with a sodium flow of 3 gpm, ond then shut down on July 18, 1955, because of the failure of the 250-kw transformer. The loop was restarted on August 27, 1955, with a projected operating period of 1000 hr with 100 thermal cycles. One cycle represents 4 hr of operation at high power, during which the sodium enters the test section at 1150°F and is heated electrically to 1300°F, and 4 hr of operation at low power, during which the sodium enters the test section at slightly less than 1300°F and leaves at 1300°F, L 9P Patriarca et al., ANP Quar. Prog. Rep. Mar, 10, | L 1955, ORNL 1864, p 134, ,__547 COLD TRAPS ANDPLUG |NVDICA-T0RVS' F. A. Anderé_on University of Mississippi J. J. Milich Pratt & Whitney Aircraft A survey of the literature and of the available experimental data was undertaken to obtain infor- “mation on the use of cold traps as devices for removing or controlling the presence of undesir able impurities, especially oxygen, in sodium- ‘or NaK«filled Inconel systems and on the use of plugging indicators as devices for determining the oxygen content of sodium or MaK streams. In addition to information obtained from the litera- ture, supplementary data were obtained during " visits to the Knolls Atomic Power Ldboratory, Argonne National L aboratory, Mine Safety Appli- ances Company, and North American Aviation, Although both diffusion and circulating cold traps have been shown to be capable of reducing the oxide content of liquid sodium or NaK to values corresponding to the saturation concentrations at the cold trap temperatures, specific data are not available which will permit sound engineering designofcoldtraps. Diffusion or natural-convection cold traps do their work much more slowly than cir- culating or forced-circulation traps and, so far, have been of primary interest only in relatively small-volume systems (up to a few gallons capac- ity). The existence of fairly strong eddy currents in diffusion cold traps is suspected. If such currents existed, their effects would overshadow completely the effect of natural diffusion. It is evident that experimental work would be required to obtain a basis for the design of diffusion cold traps. Circulating cold traps have the important advan- tage of lowering the oxide concentration of a sys- tem rapidly. Present conventional designs that provide for holdup times of 5 min and superficial liquid velocities of the order of 3 fpm give system cleanup times that correspond to three system charge turnovers through the trap. Cold traps having volumes ranging from about 3 to 10% of the volume of the system have been utilized suc- cessfully. Although microporous filters are con- sidered to be unsatisfactory in cold traps, the use of a packing material such as York demister packing has been shown to raise cold trap effi- ciencies from 68 to about 98%. Packing is used L * to provide sufficient surface to hold the precipi- . tated oxide, but it is not intended to function as ' a filter medium, _ On the basis of the collected data and arbitrary i° specifications, three circulating cold traps have been designed, one for a relatively large, 80-gal system and two for a relatively small, 4000-ml (~1-gal) system, Figs. 2.13, 2.14, and 2.15. These designs are not necessarily optimum; that is, it is felt that they will lower the oxygen content : of the system, but they may be larger than neces- sary and may have more cooling or heating capacity than that required. The traps are expected to operate at 400°F and to reduce the oxygen con- tent of the main liquid metal system to the cor- responding saturation value of 50 ppm. During operation, precautions must be observed to prevent the saturation temperature of the liquid metal with respect to oxide (Na,0) content being reached * ~ at any point in the system other than in the cold trap. If the saturation temperature were reached outside the cold trap, precipitation of oxide would occur at that point and plugging of a pipe or some other sysfem component would occur. Because of the difficulty of making rehoble de- terminations of the oxide content of molten sodium or NaK by chemical procedures, considerable use -~ has been made of the plugging indicator as a - simple device for determining the oxide content indirectly. Although there is some disagreement '—fi 2 o l—‘ My in, 3/g-in. PIPE, SCHEDULE 40 THERMOCOUPLE WELL, 2 in. LONG % o] l* g ""'uss ‘/2 i DA HOLES T 4-in. PIPE, SCHEDULE 40 . " LEACH END TO BE PROVIDED [ &in " WITH 1-kw WRAP-AROUND OR CALROD HEATING ELEMENTS ‘_ UALL WELDS CRITICAL HELIARC Yo-in. PERFORATED PLATES (TACK WELD IN PLACE) | PERIOD ENDING SEPTEMBER 10, 1955 as to the exact significance of the results, in- vestigators at KAPL feel that the use of a plugging indicator is a reliable and accurate method for determining oxide contents to within 10.001%. Unfortunately, as in the case of cold traps, the design of plugging indicators is, at the present time, more of an art than a science. Because the design first used at KAPL proved to be satisfac- tory, and because of lack of time, no effort has been made to determine whether a better design could be developed. A plugging indicator consists of a perforated plate (containing 15 to 21 holes 50 mils in diam- eter) placed in a l-in. line through which molten metal flows at the rate of 1 gpm (~10 fps through the indicator plate holes). The flowing stream is cooled until the oxide saturation point is reached, at which time precipitation occurs. When the pre- cipitated oxide partially plugs the perforated plate, a change in the flow rate occurs. The temperature at the plate corresponding to the change in flow rate, measured with an electro- magnetic flowmeter, is taken to be the plugging temperature, Although this temperature can be used as a relative indication of the purity of the liquid metal stream, it is common practice to translate the plugging temperature into an oxide concentration by means of a solubility curve. A recommended design for a plugging indicator and a bypass loop is shown in Fig. 2.16. UNCLASSIFIED ORNL-LR~DWG 2053 Y4-in. COPPER COOLING COILS (BRAZE IN PLACE) Ya- x 0.035-in. THERMOCOUPLE WELLS, 2% in. LONG YORK DEMISTER PACKING {INCONEL) Y4-x 0.035-in. THERMO- COUPLE WELL, 2 in, LONG ¥g~in, PIPE, SCHEDULE 40 z —— 2in: g Y, in.»‘ }-« DRAIN LINE, Y2~in. PIPE, SCHEDULE 40 (END TO BE CRIMPED AND WELDED) Hn." r-— 8 in.————— sgedion s i . USE INCONEL EXCEPT AS NOTED [ S e * Fig. 2.13. Circulating Cold Trap for Large-Yolume (80-gal) Systems. 55 N T 56 ) ANP PROJECT PROGRESS REPORT " UNCLASSIFIED ~ ORNL—-LR —DWG 9054 NOTES : {. EACH END TO BE PROVIDED WITH {-kw WRAP-AROUND OR CALROD HEATING ELEMENTS. 2. ALL WELDS CRITICAL HELIARC, 3. USE INCONEL EXCEPT AS NOTED. Y,-in. SCH 40 PIPE '3 ~in. THERMOCOUPLE WELL Y4-in. COPPER COOLING COIL | . J/ (BRAZE IN PLACE) ! din. s / l=-Yg-in. END PLATE o NOTE ,//2 in. SCH 40 PIPE - E = > . ~—LIQUID IN . = é —1in = i , I »1' 7 ~8in e T 4in——= YORK DEMISTER PACKING 1 | : " PLATE DETAIL ! (INCONEL) ; : e 3 R 3-in. SCH 40 PIPE ——DRAIN LINE (CRIMP AND WELD END) , . USE “g-in. DIA. HOLES _ Yg-in. PERFORATED PLATE E L e e e (TACK WELD IN PLACE) E 3 . F ; r > i 10 1t 2 3 18in. mmwmm onom s ans T e INCHES . Fig. 2.14. Circulating Cold Trap for Small-Volume (~ 4000-ml) Systems. UNGLASSIFIED - ORNL-LR-DWG 9055 YORK DEMISTER PACKING {INCONEL) /4 -in. COPPER COOLING COIiL V4-in. THERMOCOUPLE WELL, 1% ~in. LONG {BRAZE IN PLACE) F— 134 in. 1-in. SCH 40 PIPE i \ =Yg ~in. PLATE 3in 10in. 10in. NOTES: 1. USE INCONEL EXCEPT AS NOTED. 2. ALL WELDS CRITICAL HELIARC. f 0 1 2 3 . INCHES Fig. 2.15. Alternate Circulating Cold Trap for Smali-Volume (~ 4000-m!) Systems. i b UNCLASSIFIED ORNL~LR-DWG 2056 i‘ PERIOD ENDING SEPTEMBER 10, 1955 4 ; . MAIN SYSTEM —~ VALVE ——= ~—— VAL VE ELECTROMAGNETIC ELECTROMAGNETIC FLOWMETER PUMP PLUG INDICATOR PLATE - 4-in.TEE f-in. SCH. 40 PIPE —" it i R e it b Y4-in. THERMOCOUPLE WELL 1-in. SCH. 40 PIPE AACHINE END TO FIT INTO TEE AND AGAINST PLUG PLATE AS SHOWN) L e - 0049-in. 7 7 orR * ’ . NO.16 BWG PLUG INDICATOR PLATE v | STANDARD {-in. TEE ' OR EQUIVALENT | | | 2 | | L . 1-in. SCH 40 PIPE - (MACHINE END TO FIT INTO TEE AS SHOWN) sy V/ 2 % Y&-in. COVER PLATE _/ (WELDED IN PLACE) Y4-in. THERMOCOUPLE WELL (TO EXTEND TO %-in. FROM PLUG PLATE) USE WRAP-AROUND HEATERS ON ALL LINES TO CONTROL TEMPERATURES AND COOLING RATES 57 ANP PROJECT PROGRESS REPORT 3. CRlTICAL :E'X‘PVER)IMENTS_ A. D Cclllhan V. G. Harness J. J Lynn - E, ‘R' Rohrer Apphed Nuclear Physacs Division R. M Spencer, Umfed States Air Force D. Scott, Jr., Asrcraft Reactor Englneermg Dmsnon J. S. Crudele E. V. Sandln | S. Snyder Pratt & Whlfney Aircraft S ROOM-TEMP ERATURE REFL ECTOR- MODERATED-R EACTOR CRITICAL ¥ EXPERIMENTS " A c:rmcal assembly of the reflector-moderated - _circulating-fuel reactor loaded with sufficient if-f"}siUz’?’fs to give about 3% excess reactivity was de- 'scrlbed prevuously. After the completion of a sferles “of experlmenfs in which the excess reac- ““tivity was utilized to measure certain reactivity coefficients and the effects of various structure changes, the assembly was reloaded in order to determine the clean critical concentration more exactly. With the same structure and dimensions as those reported previously, the U235 concen- tration was reduced from 0.416 to 0.345 g per cubic centimeter of fuel region, equivalent to a loading of 20,07 kg of U233, and the assembly (CA-21-2) was critical with only 0.14% excess reactivity. This assembly is compared in Table 3.1 with the assembly (CA-21-1) which had 3% excess reac- tivity. Two structural changes in the assembly have also been investigated. In one modification (as- sembly CA-22) the average width of one of the end ducts, the portion of the assembly that simu- lates the fuel flow channels into the reactor core, was increased from 1.29 to 2.80 in. to make its volume almost 2.5 times that of the originally constructed end duct. This change was made because consideration is being given in the re- actor design to the possibility of using end ducts of larger cross section, The increased fuel capac- ity of the assembly necessitated the addition of U235 in the end ducts, which made a total of 28.35 kg of U233 gt an average density of 0.405 g ;_of_u U_2_35 per cubic centimeter of fuel material. 7 ]A.. D. Callihan et al.,, ANP Quan Prog. Rep. March .10, 1955, ORNL-1864, p 41. The array was crmcal wn‘h 3 2% excess recchvny, ' and the estimated ‘‘clean” critical mass was 24 £ 2kgof U235 In another experiment (CA-23), with end ducts of the original size, the average radius of the central psuedo-spherical beryllium region or ‘‘island’ was increased from 5.18 to 7.19 in., with a correspond- ing reduction in the fuel volume of from 58.2 to 44.3 liters. The use of a thinner fuel annulus is being considered in the reactor design as a means of reducing fuel self-shielding. The beryllium content of the core was increased from 67 to 92 kg, including that in the end ducts. This assembly was critical with a loading of 18.62 kg of U235 at an average density of 0.420 g of U235 per cubic centimeter of fuel region. The excess reactivity was 0.19%, and the estimated critical mass, with- out control rods, was 18.4 kg of U235, The di- mensions of assemblies CA-22 and CA-23 are given in Table 3.1, along with the data obtained with these assemblies. HIGH-TEMPERATURE REFLECTOR-MODERATED-REACTOR CRITICAL EXPERIMENTS A low-nuclear-power, high-temperature, reflector- moderated-reactor critical experiment is currently under way, and some preliminary results have been obtained. The liquid fuel in the assembly is at 1200°F. The reactor section of the equipment closely resembles the current design of the ART. It consists, essentially, of an annular fuel region separated from the beryllium islané"an'cl' reflector by ]/B-in.-'rhick Inconel core shells. The island, partly surrounded by the inner Inconel shell, is shown in Fig. 3.1. The outer shell, with some of the beryllium reflector in place, is shown in Fig. 3.2, A re-entrant tube is mounted along the vertical axis of the reactor to serve as a guide - h PERIOD ENDING SEPTEMBER 10, 1955 ] . . ; ‘“N% , TABLE 3"[ COMPOSITIONS AN PIM ENSIONS OF THREE-R EGION REFL ECTOR-MODERATED-REACTOR CRlTICAL ASSEMBI.IES V"ITH /8-i n.-THICK INCON EL CORE SH ELLS AND DUCTS { S Assembly NUmber S CA-21-1‘ - CA-21-2 T cAa22 cas Berylhum Islqnd | i Volume, 3 - 1,27 1.27 ' 1.27 1.75 Averqge radlus e o o e - ' " Spherical section -~ 518 = 518 5.18 7.19 "Endduets 7386 3.86 3.86 3.86 qus, kg o e 670 7.0 67.0 92,2 o Fuel Reglon (excludmg shells and : interface plates) Volume, #° 2,06 2.06 2.47 1.56 liters 582 582 70.0 44,3 Average rqd:us, m o ' o T e S ' Spherlcql secflon o Inside o 531 7 s31 531 7.32 _ Outside 944 T 944 944 9.4 o heside 399 T T 399 399 399 . : - Outsmiel A o 528 528 6,79 ' 5.28 ) - Distance between fuel sheets, in. ' 0.142 ‘ . 0.173 0.142 0.142 . Mass of componem‘s, kg ‘ e I . - Teflon | 7 108.88 ° ~ 108.18 126,77 81.54 ' L Uranlum |oad|ng S 26,02 21.57 30.45 19.97 - U235 foading - 24.24 20.07 28.35 18.62 = . _ Uranium dens:ty,b g:;/cm3 | 0.446 : 0.370 0.435 0.451 ouBs density,® g/em’ 0.416 0.345 0.405 0.420 Uramum couhng materlal IR 0.25 0.21 0.30 0.19 Scofch 1qpe ' ' ' 0.15 0.15 0.15 0.15 " Core Shells and lnferfoce Plafes ¢ S o Mass‘of components, kg ' | aOnfy one end duct was énlarged. . Mass per unit volume of fuel region. : e “Mass required for a critical system with the poison rods removed. § ; 59 ~ :ANP PROJECT PROGRESS REPORT Fig. 3.1. Partially Assembled 1sland Showing Lower Half of Inconel Inner Core Shell and the Upper Half of the Beryllium Reflector. for the annular control-safety rod, which contains a mixture of the oxides of the rare-earth elements. The rod is magnetically supported and can be positioned above the horizontal mid-plane for con- trol. It is free to fall below the mid-plane for reactor shutdown. The outside diameter of the neutron-absorber section of the rod is 1.28 in., and the annulus is T/8 in. wide. The density of the neutron-absorber compact is 6.5 g/cm?; its principal constituents are Sm,0, (63.8 wt %) and Gd,0, (26.3 wt %). The support and the driving rod for the neutron source are coaxial with the control rod. The beryllium blocks in the reflector and the island are in an atmosphere of helium; there is no sodium in the system. The reactor is mounted above a reservoir for the liquid fuel, which is a mixture of the fluorides of sodium, zirconium, and enriched (93% U235) uranium. The fuel is transferred to the reactor by applying helium under pressure to the liquid surface in the reservoir; the return to the reservoir is by gravity. The temperature of the system has been raised to 1350°F by electrical heaters located external to the reflector and the fuel reservoir. The completed assembly is shown in Fig. 3.3. After an initial test of system operation and leak tightness with an equimolar mixture of NaF and ZrF,, successive increments of Na,UF, were added until the reactor became critical, The fuel concentration was then 6.30 wt % (2.87 mole %) vranium, and the excess reactivity, determined from the subsequent calibration of the control rod, was about 0.13% Ak/k. A measurement of the over-all temperature coefficient of reactivity be- tween 1150 and 1350°F showed the value to be negative and equal to 2 x 10=5 (AR/E)/°F. An increase in the uranium concentration of the fuel from 6.30 to 6.88 wt % resulted in an increase in reactivity of 1.3% Ak/k. The control rod has a value of 1.7% Ak/k when inserted to a point 4 in. above the mid-plane. ' ‘ PERIOD ENDING SEPTEMBER 10, 1955 P, : Fig. 3.2, Outer Core Shell and Partially Assembled Beryllium Reflector of High-Temperature Critical ‘; Assembly. PHOTO 24440 3. T ircul&iing-F-uél R‘eddb"r_.: Moderated Ci ssem al A 1C Cr h Temperature 3 blf of the Reflector- i L el T B 3 * 4 -« ~ - Part i ' MATERIALS RESEARCH | \ . & ) . e A x : = . o | . L e o T T R T e Ty b s . [4] RN M i . euSdSNEL G G - B W 4, CHEMISTRY OF REACTOR MATERIALS W. R. Grimes Materials Chemistry Division Phase equilibrium studies were made of the LiF-ZrF,, UF,-ZrF,, NaF-LiF-ZrF,, NaF-LiF- UF,, NaF-RbF-ZrF -UF,, KF-ZrF,, and NaF-KF- ZrF, systems and of the BeF ,-containing systems NGF-LIF BeF,, NaF-LiF-BeF,-UF,, NaF.BeF,- UF,, K F- BeF and NaF-KF-BeF,. A revised equalnbrlum d:agram for the LiF-ZrF, system is presented., Additional data were obtained on the solubility of UF, in BeF,-bearing compositions, Additional work was done in investigating the equilibrium reduction of FeF, by hydrogen in NaZrF, the reduction of UF, by structural metals, and the stability of chromium and iron fluorides in molten fluorides. The experimental preparation of NH,SnF; and of compounds of ZrF, with CrF,, N|F2, and FeF, is described. The mveshga’r:ons of the reaction of UF, with uranium in alkali fluo- rides and the reaction of uranium metal with alkali fluorides were continued. Studies of the reactions between molten fluorides and metals included some exploratory work on the equilibrium between so- dium-potassium alloy and NaF-K F melts at 800°C, Fuel purification and production research in- cluded the investigation of methods for the re- covery of confaminated fuel for re-use and the conversion of ZrQ, to ZrF, in the present produc- tion equipment, The studies of processing techs niques for the purification of BeF, Thermal breaks in the range 45 to 50 mole % ZrF, indicate that there are two forms of KZtFg, one of which is metastable. | The System NaF-KF-ZrF, H. A, Friedman R. E. Thoma Ma’rerlcls Chemistry Division F’reltmlncry studies indicate that the NaF-KF- ZrF , system is much more complex than either the NaF-ZrF -UF, system or the NaF-LiF-UF, sys- tem., Neither of these latter systems shows ter- nary compounds; in contrast, the NaF-KF-ZrF system shows at least five such compounds. One compound has the composition NaF:KF.ZrF,, and another has the composition 3NaF.3KF.2ZrF . Although the latter compound forms a compatibility ~ triangle with NaF and K, ZrF,, it cannot form a quasi binary with K ZrF,, NasZrF,, or NaF, be- cause it apparem‘ly melts mcongruenfiy at about - 755°C to K ZrF and liquid. Cooling curves on - the Na,Z:F -K ZrF join show a minimum in the ' !iquidus femperm‘ures' at about 800°C for the com- . position with about 15 mole % KF; the liquidus ' temperatures then rise gradually to about 918°C - for-the compound K ZrF and about 850°C for the 'VCompound Na ZrF7. Smce a slowly cooled melt of -~ a compesition mldwcy between 3NaF.3KF.2ZrF, * “and NaF- KF. ZrF4 consists of only these phqses, it can be concluded that this join is a common base of two, as yet undetermined, compatibility triangles, SL M. Bratcher, R. E. Traber, Jr., and C. J. Barion, ANP Quar, Prog. Rep, June 10, 1952, ORNL-1294, p 91, Fig. 43. PERIOD ENDING SEPTEMBER 10, 1955 Eight melts were made along the 33.3 mole % ZrF, join of compositions containing from 15 to 50 mole % KF and NaF as the remainder, Although all these compositions contained the compound NaF:KF.ZrF, as one of the phases in the com- pletely crystallized preparation, liquidus-tempera« ture relations indicate that the compound melts incongruently and that therefore there is no quasi binary along this join, Melting relations and phase compositions of six preparations along the 47 mole % ZrF, join indi- cate that the mixture with 47 molé % ZrE, also is not a quasi binary, because most of the composi- tions consist of three solid phases, including a new ternary compound of undetermined composition that is probably near NaF.2KF.3ZrF,, The mini- mum liquidus temperature along this join is about 420°C for a mixture with about 35 mole % KF, A search in this general area has indicated that there is a eutectic, with the approximate composi- tion 38 mole % KF, 21 mole % NaF, 41 mole % ZrF ,, which melts at about 400°C, PHASE EQUILIBRIUM STUDIES OF SYSTEMS CONTAINING BeF2 C. J. Barton and F. F, Blankenship L. M. Bratcher R. J. Sheil B. H. Clampitt R. E. Thoma Materials Chemistry Division R. E. Cleary, Pratt & Whitney Aircraft T. N. McVay, Consultant The System NaF-LiF-BeF, Thermal analysis data were obtained with a num- ber of compositions within a wedge-shaped areaq in the temary diagram having the LiF-Na,BeF, eu- ~tectic (16 mole % LiF) at the apex and Na,BeF, and NaF-BeF, (70-30 mole %) at the other corners. The cva:lub[e data indicate that acceptably low melting points can be obtained with low LiF con- ceniration by moving into the ternary system along the drainage path leading from the NaF-Na,BeF, eufectic (approximately 31 mole % BeF,; melting point, 570°C) toward the LiF-NGzBeF4 eutectic, Further, viscosity data for BeF -bearing mixtures indicate that, in order to obtain a melt with a kinematic viscosity as low as that of the ARE-type fuel (2.82 centistokes at 600°C and 1.34 centi- stokes at 800°C),% the BeF, content of the melt 6s, 1. Cohen, ANP Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 157, 69 ANP PROJE’CT PROGRESS kEPORT must not be greater than 30 mole %, to assure com- plexing of BeF, as BeF,=~ ions in the melt, If an NaF-LiF-BeF, mixture is desired, it also ap- pears that the LiF content will probably have to be less than 10 mole %. One composition that ‘meets these requirements is the mixture NaF-LiF- BeF, (63.,5-7.5-29 mole %), which has a melting point of about 525°C, It is expected that the viscosity of this mixture will be determined in the near future, The low-melting ternary mixture NaF-LiF- BeF (27-35-38 mole %), reported previously’ on thev “basis of cooling540 540 27 35 38 Visual 355 | 339 S Filtration >355 339 63.5 .5 31,_5 .7 fDane-renhal thermal analysns - 537 545 to 555 mixtures °,f. dbpm*iffi?}e!y'V'fHé’_?O-’BO mole,-%:.éom- ‘posifion. Differential thermal analysis data ob- tained with rapidly cooled samples of the mixture - NaF-BeF ,-UF, (68.25-29.25-2.5 mole %) indicated a probable liquidus temperature of 579 + 5°C, Filtration data obtained wn‘h the mixture NoF- _Ber-UF4 (66 8-30.7-2.5 ‘mole %) showed the liquidus temperature fo be below 562°C. The highest thermal effect observed on cooling curves with the lafter composition was ot about 555°C. There appears to be little hope of obtalnmg an acceptable hqmdus fempera’rure with a ternary mixture of this fype confammg 25 mo[e % UF, cnd 30 mole %, or Iess, BeF The System KF-BeF Thermcl 0na|ys:s ‘data recem‘ly ob'ramed wn‘h_'_ punfled mixtures in the KF-BeF2 system showed sllghfly h|gher melhng pomi's than those obtmned{ " ,,,,, P . mcongruem‘ly at 390°C and g;vesfl‘K BeF £ Thermal anulys:s data on. abouf:"40 unpurified " melis in the NaF-KF-BeF, system were obtained - prewously.H The mcomplete inve .tlgcmon showed rather high liquidus temperatures, as compared with those of the NaF-LiF-BeF, system, and no promising fuel carrier compositions were formu- lated as a result of these studies., Recent interest in obtaining a BeF -buse fuel cartrier with low kinematic viscosity prompted a reinvestigation of the l\]c::[:--KF--BeF:2 system. Thermal analysis data obtained with temary compositions prepared from purified binary mixtures have served to confirm the earlier indications of high liquidus temperatures in this system, particularly for the mixtures con- taining 33 mole %, or less, BeF,. The mixtures containing 33 mole %, or [ess, BeF are considered to be the most promising maxtures from the vis- cosity standpoint, Preliminary results of petro- graphic and x-ray diffraction examinations of a number of slowly cooled melts show that composi- ‘tions on the NaF-K. ,BeF, join contain only these two componem‘s. Thermal analysis data for this system, shown in Fig. 4.2, indicate that it is a _simple eutectic " systém, with the eutectic con- - L R e g a ouf{»_’?g‘_AS mole 7 NoF cmd havmg a melt- J P. Blakely, L. M. Bratcher, and C. J. Barton, ANP Qua:r. Prog. Rep. Dec, 10, 1951, ORNL-1170, p 87. 71 compounds are”’NaKBeF ancf Na K(BeF4)2. An e I f th_e rpha ehevedr_ 'rqv be N K BeF “and the fernarym ANP PROJECT PROGRESS REPORT “c UUNCLASSIFED ¢ ORNL-LR-DWG 9480 1000 o= 900 : ™~ 700 800 O e - L o 3 |._ < e Sw S = Lo '_ © 500 CNeF T 40 20 30 40 50 60 70 80 790 KyBeR, K,BeF, (mole %) Fig. 4.2. Thermal Data for the System NaF-K BeF,. Solubility of UF; in BeF,-Bearing Compositions Data on the solublllty of UF; in a number of BeF .bearing compositions were reported earlier.12 The composition(in mole %) designated 69 NaF-31 BeF, in the previous work was actually 69 LiF-31 BeF,. All the earlier data were obtained with mckel filters.1® In view of the greater stability of UF, dissolved in LiF-NaF in copper containers (discussed below in this section under the heading ““Reaction of UF, with Uranium in Alkali Fluo- rides’’), it seemed desirable to see whether more consistent data could be obtained in copper ap- paratus equipped with a bronze filter medium, The data obtcuned are shown in Table 4.2, together ‘with some addmonol dm‘u obtained with LiF-BeF, mixtures in ‘nickel apparatus. The uranium addt- ~ tions were made erh UF, and uranium metal or by 'addmg large excesses of uranium metal to UF,- beormg melts, It is difficult to draw definite conclusions from such scah‘ered data, but it is apparent that alloying o of uramum wnh the nlckel filters and containers o ]2L. M Bratcher et al, ANP Quar. Prog. Rep. June 10 1955, ORNL-1896, Table 4. 2, p 38, R L M. Bratcher et al, ANP Quar. Prog Rep. March 10 1955. ORNL 1864 p 51 was not the sole cause of the poor reproducibility of the UF .solubility data obtained in nickel ap- paratus. The large amount of tetravalent uranium found in all the filtrates, regardiess of valence form of the uranium added to the soivent, could be due to oxidizing impurities in the melt, dispropor- tionation of UF,, or a reaction between UF; and the alkali fluoricj’e or beryllium fluoride in the melt, Further experimentation will be required to deter- mine the controlling factor in the production of UF, in BeF,-bearing compositions. CHEMICAL REACTIONS IN MOLTEN SALTS L. G. Overholser G. M. Watson Materials Chemistry Division . Equilibrium Reduction of FeF, by H, in NaZ¢F, C. M. Blood Materials Chemistry Division An apparent equilibrium ‘;ldln"stfir_i'f (molefrochon ) of dissolved species used as activity) of 5.7 at 800°C was previously re.-pm'\‘ec!14 for ’rhe reachon FeF, + H, ;—.:_‘ Fe + 2HF Y. M. Blood, ANP Quar, Prog. Rep. June 10, 1955, ORNL-189, p 6. il -y T T PERIOD ENDING SEPTEMBER 10, 1955 TABLE 4.2, SOLUBILITY OF UF, IN BeF,-BEARING COMPOSITIONS Temperature Container Analysis of Filtrate Uranium Solvent Composition o) Haterial Added (wt %) us? Total U LiF-BeF, (69-31 mole %) 700 Nickel UF5 + U 2,79 4.80 700 Nickel UF, +U 3.38 5.66 a | 800 Nickel UF, +U 8.35 14.1 i 800 Nickel UF, +U 8.28 12.7 600 Copper UF, +uU 0.46 3.12 . : 700 Copper UF, + U 3.09 5.34 800 Copper UF, +U 5.02 12.7 NaF-BeF , (70-30 mole %) 600 Copper UF, +U 0.40 2.50 600 Copper UF, +U 0.19 7.05 700 Copper UF3 + U 2,75 5,24 ‘ 700 Copper UF, + U 4.82 10,1 800 Copper UF, +U 10,1 14.7 ’ 800 Copper UF, +U 12.2 19,1 ° when the materials were contained in a mild steel of iron. From all apparent indications, the ap- system. This value was obtained by passing hy- - - drogen at different gas flow rates through the salt mixture containing FeF, and measuring the cor- responding partial pressure of HF in the effluent, An approach to the equilibrium partial pressure of HF was made by extrapolation to the slowest flow rate, As has been stated before, !5 the extrapola- . tion does not c:ppear to be saflsfaci’ory. H2 through The melt con | '5c. M. Blood ANP Quar.' ORNL-1864, p 57. * ' 16C, M. Blood and G. M. Watson, ANP Quar, Prog Rep. Sept. 10, 1954, ORNL-1771, p 66. i order to avoud fhls exfrapolatlon, measure- ments made bY Us'ng an ethbruhon fecthue:m : - "prewously descrlbed 16 have been continved, The , **“method cons:sfs in bubbhng a mixture of HF and ‘ | nmg FeF2 in contactv'::"‘j"”"'“:"' ntil the HF <.:on't:em‘rc|1hons»\oW}c the '"'-.,,., p o S corresponchng ’ro 6490 ppml proach to equilibrium in this instance was better than that for any previous measurement obtained by this technique. Unfortunately, the existence of equilibrium cannot be demonstrated with certainty, since the present equipment cannot provide a gase- ous influent of constant composition for long periods of time. An alternate method of formation of H,-HF mixtures of constant composition is presently being studied. Reduction of UF, by Structural Metals J. D. Redman C. F. Weaver Materlals Chemlsfry DlVISIon The techmques used for measurmg ‘the reduchon | “of UF by Ct° or Fe® in molten fluorides were de- scrlbed in earlier reporfs.17 Equilibrium data for riginc1|I request for 4750 b to 1150 Ib of processed fluo- rides for this period; however, to prevent a pos- sible shortage of material for ORNL-ANP usage ~while the ZrF, supply problem is being resolved, - “only 750 1b of materlcl was shipped to them. Other ';.—']off-qreq shipments included 44 Ib to Wright Air M Developmem‘ Center and 73 Ib to Baflelle Memonal Institute. Successful attempts to fill four 50-|b cans simul- taneously from a 250-1b batch were made, and the practice was extended to smaller batches. The time required to perform these opercmons was, accordingly, reduced ' Loading and Draining Operations N, V. Smith Mcn‘enols Chemlstry Dwns;on _ The operohons necessary for fl!llng, drcumng, and sampling of charge material in all test equip- - ment other than the thermal-convection loops have continued at a rate comparoble to that of the previous quarter. Over 50% of the operations have involved the handling of alkali metals. With the rapid increase in festing of alkali metals, con5|derqt|on of safe, rapid methods of disposal of used metals became necessary Commercial vendors will not accept the metals for reprocessing. The small-scale methods of disposal formerly used have become inadequate for the quantities now involved. Information ob- tained from the Mine Safety Appliances Co. led to the installation of an underwater jet through which NaK is forced at 30 psi under 10 ft of water in the disposal quarry. It is now possible to dispose of NaK at a rate of about 30 |b/min. With proper heating of the lines leading to the jet, this installation could be used for sodium disposal. The ART high-temperature critical assembly was loaded with approximately 750 Ib of NaF-ZrF, (50-50 mole %) and sufficient NaF- UF, (66.7-33.3 mole %) to reach criticality. Most of ?he NaF-UF was added by helium pressure transfer of fhe molten material in approximately 5-1b increments. The final titration to criticality was made by using the enriching system designed by the ARE Division for the experiment; the enrlchmg system had pre- viously been filled with fuel concentrate. After each significant addition of N02UF6, the ‘sump was sampled; the uranium content was determined by the ANP Analytical Chemistry Group. Enriched Fuel Preparations J. P. Blakely F.A. Doss 'J. E. Eorgan Materials Chemistry Division The relocation and installation of processing equipment sunfdble for prepara'rlon of enrlched' i alicu SREL - e [STCHPL T X fuel batches was completed. Two batches of NaF-UF, (66.7-33.3 mole %) containing enriched uranium were prepared for use in loading of the ART high-temperature critical assembly; four batches of material remaining from the ARE were PERIOD ENDING SEPTEMBER 10, 1955 tained in recrystallized alumina crucibles; elec- trical contact between the half cells was effected by a porous bridge of ZrO, impregnated with the NaF-ZrF , mixture, Attempts have been made to examine cells of the type ZT02 M| MF NGF(a]), ZrF 2{(satd)’ @)\l NaF-ZrF, , MF M, NGF(a by ZrF 2satd) also included in the stock available for this ex- periment, . - - One preparation of NaF-ZrF,-UF, (53.5-40-6.5 mole %) was subdivided into three small batches; one of these was transferred ihte the first in-pile loop to be sent to the MTR for testing. A batch of NaF-ZrF,-UF, (63.0-25.0-12.0 mole %) to be used in other rad:ohon damage studies was also proces sed. FUNDAMENTAL CH EM|STRY OF FUSED SALTS So]ubllrty of Xenon in Molten Sults " R. F. Newton ' Resecrch Dlrecfor s Dzvlsron Recent experlments have shown ’rhcn‘ the gas stripped from fused salts and measured as xenon was contaminated with SiF, and with some organic material that was volcmle at room temperature but trapped in liquid nitrogen. Accordingly, the previously reported?® value of about 10~7 mole of xenon per cubic centimeter of solvent for the solubility of xenon in the NaF-LiF-KF eutectic is too hlgh 2 The orgamc contammanf is presumed to ar:se,__l_,'f ,'from sfopcock grease. "The" apparatus is belng”"“m modn‘led to substn‘u A . ;Athe sfopcocks.' phere was maintained over the half ceils con- 26R, F. Newton and D. G. Hill, ANP Quar. Prog. Rep. Sept. 10, 1954, ORNL-1771, p 70. y “cutoff traps for - A barlum oxide ‘ltrqp. Is bemg m.-»-«-_ Fe® and the Fe®Ni® cells agrees reasonably well where M and M' are CrS Fe% and Ni°% These cells appear to be reversible, and they are quite reproducible. However, interpretation of the data from these cells is complicated because the solid phase in equilibrium with the melt is not the simple metal fluoride; evidence reported in a previous portion of this section suggests strongly that complex compounds of which NiF,:ZrF, is typical ‘are formed. Accordingly, when M and M! are both Cr® for example, and when the two half cells contain CrF, in different amounts, both sufficient to saturate the solution at temperature, small but reproducible and significant potentials are ob- served. For example, when one half cell contains 7.8% and the other contains 12.6% CrF, (solubility of CrF, at 700°C is 5.8%), the emf of the cell varies from 15 mv at 550°C to 8 mv at 700°C. This potential arises because the CrF, added in excess of the saturation concentration ‘‘pre- cipitates’’ ZrF 4 and thus changes the composition of the solvent and affects the activities of the ZrF, and of the NaF to a different extent in the two half cells, Potentials measured at various temperatures for - cells of this type are shown in Table 4.15. It ‘may be noted that the sum of values for the Cro- at all temperatures with the values for the Cr°- Brawer's27 estimates of free energy of formatlon Tare assumed to be correct, E0 ‘values of 0.35, 0.25, “and 0.60 v are obtained for the CroFe® . Fe®Ni% and Cro-Nj° cells; these values should "_,be nearly mdependent of temperature over this interval. 27) . Brewer e: al., p 107 in Chemistry and Metallurgy of Mz.scellaneous Materzals, Thermodynamics (ed. by L. Quill), McGraw-Hill, New York, 1950. 85 N| cell If the solld phase in ethbr:um' with __'rhe'\' “melt were the simple fluoride MF and if Sl e g e kel ok B g B s b ok G R i "ANP PROJECT PROGRESS REPORT Reproducible emf values have been obtained for cells of the type o : . . Zr0, . o Cr Cer(Cl)' NaF(a]), ZrF4(a2) NGF(“%" ZrFMa;), CrF2(C2) Cr° , 3 where ¢, is less than the saturation concenfra- tion of CrF, and c, is more, Data for three such cells for which ¢, was 0.90 wt % Crf, and c, had the values shown are presented in Table 4.16. Additional studies of similar, but less complex, cells of this general type are to be made, While a partial interpretation of the available data would NdF-ZrF4 ~are _qflfg_ampied, | b % . ' T T T T TR TR YO WP RIS T PR additional experimental effort appears to be de- sirable before such evaluation and interpretation -~ A number of cells were run to determine the feasibility of employing a platinum wire as an electrode for half cells containing mixtures of 4 be possiblé by making use of several assumptions, FeF, and FeF, in NaF-ZrF,. These cells, as TABLE 4.15. POTENTIALS OF CELLS OF THETYPE Bl il bt i i o o i Zr0 : 2 . i ] M IMF o(saray NoF(q y ZrF 4q,) NaF-ZiF NaFady ZF o ly M Fa(sara) | M - b a ' B c Summation of ’ Measured EMF (v)* ‘ > Temperature - Cro%Fe® and Fe2Ni° ¥ (OC) Cfo‘Feo** Feo’Nio** Cf 'Nio** Values (V) -3 550 0.342 0.408 0.754 - 0.750 600 0.345 0.415 0763 0.760 650 0.361 0.422 0.773 0.783 700 0.424 0.374 0.788 0,798 *Mean of values from two similar cells, *_*Cer concentration, 7.6 wt %. Fe F2 concentration, 7.3 wt %, " Ni F2 concentration, 5.0 wt %. TABLE 4.16. POTENTIALS OF CELLS OF THE TYPE Zr02 ' O Wiel = ¢ - e,y NQF(alj' ZFF4(02) NaF-ZeF , NaF Cr,Wnrhc] 0.90 wt % o C!" CrF (a})’ ZrF4(a;), ch"""z) Measured EMF {v) : rTein'ilpercrfl.ure -' °C) cy = 6.6 Wt % cQ TTTwt% T ey = 90wt % 550 ' 0.008 0.013 0.014 600 0.032 0.038 0.040 650 0.050 0.058 0062 0.061 0063 700 0.052 86 - - + e it . e ey QLA WG .y G g ofbod Lk o - a® “a lu'rfi‘i'n'd , Vfoneousiy as part of a ce “that cell. electrode becomes effechvely a chromium elec- well as others, such as |, UF, Pt and Pt CrF, UF, gave irrepreducible potentials. - Two uranium rods dipped into a solution of UF, in molten NcF-ZrF4 showed approximately zero emf from 550 to 700°C, It is possible that uranium acts as a reversible electrode at these temperatures., Activity of Chromium in Inconel M. B. Panish Materials Chemlsfry Division As «d foundaflon for future studies of thermo- galvanic effects in fused-salt melts contained in Inconel systems, an attempt has been made to determine the activity of chromium in Inconel. The elec‘rromohve forces of several cells of two types have been determined over a temperature range of 550 to 800°C., The cells being studied are: (D Cr |NaF, ZrF,, CrF, Inconel and (2 Cr|NaF, ZeF,, CrF, The fused-salt melt used in ffiis work was NaF- . ZrF4 (53‘47 mole %), Wl'llch wcv:. sa'run_'ated w:th_v_'_ Cri':2 to ensure an |‘dent|ca|“ chromlum concentrc_ R4 ~ tion in the anode and ccfh e ccm‘lpdr fme"f5° The '>unde_r a__dry he[ium qtmqsphere. e T e e fi’«f—,f_ SARAEREN Thls seems t AlL0, (satd with melt) PERIOD ENDING SEPTEMBER 10, 1955 trode as a result of an internal discharge in cells of type 1. A reaction that might possibly occur is 3CrF2-T-__"2CrF3 + Cr°® If such an equilibrium did exist, there would be a different equilibrium concentration of CrF, and CrF, around each electrode because of the differ- ence in concentration of metallic chromium in the electrodes. If, as in cells of type 1, it is possible for convection currents to carry solution from one electrode to the other, an internagl discharge of the cell may occur, Cells of type 2 are obtained experimentally by using two recrystallized alumina containers, one within the other. The electrodes are placed so that one is in the inner container and one is be- tween the two container walls. The salt mixture is placed in and around the inner container. The results obtained with cells of type 2 are somewhat erratic, but there is a general trend that is shown by the data plotted in Fig, 4.4. Further investigation will be necessary to clarify these results. Particular attention will be paid to the purification of starting materials and to Inconel . NaF, ZrF ,, CrF, fhe chromous-fo-chromlc jon raflosl m fhe ce” com ' under‘ihe c'ondmons of 'rhl's work._ | T Very little 'has been done fo determine the polar- lzablhty_ of the lnconel elecfrodes. After a small indicate fha’r the lncone] “amount of curren'r “is passed ina ceH of type 2, the momtencnce of a water- qnd oxygen-free atmos- phere. It will also be necessary to investigate a fyp:cal ‘melt used for cells in this work _ |_s shown in Flg. 4.5, Alfhough the current across i, S y electrocles wQs reversed after q co_nSlderable e‘no’r the cell appears to recover slowly, 87 E E i . .§. e R R ki ks e dae de 2 ¢ ol bl Rk | i 'ANP PROJECT PROGRESS REPORT .. * 'UNCLASSIFIED “ "ORNL—LR-DWG 9181 1.2 1.0 DATA TAKEN AT 7 s T00°% HE o T00°C A 750°¢C . ..08 A 700°C W 0.6 04 \"-..._._‘_ '--..,_._‘ \‘ "-.._- \ e \"\A \-..___._. e ".__-_‘_ . . — Se—A : "—'-—--——.a...._.:;—. e . T A e e e A —_——= 0 0 5 10 15 20 ) 25 TIME (hr) . . Fig. 4.3. Discharge of Type 1Cells. VYiscosities of Molten Nitrates F. A. Knox F. Kertesz Materials Chemistry Division The capillary viscometer, previously described,?® has been calibrated by using pure LiNO, and KNO, and has been used to measure the viscosity of a mixture of these materials. Attack by LiNO, on glass at high temperatures has necessitated sub- stitution of a nickel capillary for these studies. Measurements obtained?® for KNO, are in close agreement with those reported by Dantuma?? and by Goodwin and Mailey.3? Values for LiNO, agree reasonably well with those presented by Goodwin and Mailey but are nearly 20% below those of Donfuma. A mixture of the two salts (62.2 wt % KNO ) shows a |1necr reiatronshlp befween |og vnscosn‘y e 2%, 28 (1 908) F. A Knox,F Kerfesz, und N. V. Smlth ANP Quar, "jf,Prog Rep. Dec. 10, 1954, ORNL-1816, p 75. 29 L 33-4(1928) R. §. Dantuma, Z. anorg. u. allgem. Chem. 175, 30 M. Goodwin and R. D. Mailey, Pbys. Rev. 26, and reciprocal temperature over the temperature interval 230 to 492°C (Fig. 4.6). Below 230°C, however, the viscosity increases more rapidly than would be predicted by this relationship, The values obtained for the mixture are lower by about 15% than the values for the pure components. Optical Properties and X-Ray Patterns for Recently Discovered Compounds in Fluoride Systems R. E. Thoma Materials Chemistry Division G. D. White Metailurgy Division - T. N. McVay ‘H, Insley Consultants The identifying characteristics of some new ~ compounds encountered m phose studies are hsfed;' I below. The symbol d(A) means the distance be- tween reflecting planes measured in angstroms; I/I] refers to the relative intensity as compared with an arbitrary value of 100 for the strongest line; under optical properties, N, and N refer fo kit Mt G s o, SN, it NIRRT L A SR T « ay : - 0.4 T ' Fig. 4.5. Electrodes inan NaF-ZrF Saturated with CrF, ot 706 °C. 0.8 046 N PERIOD ENDING SEPTEMBER 10, 1955 UNCLASSIFIED ORNL—LR-DWG 9482 \\\\\\\ N\ // / - 2 fo 2o %0 40 50 6 R fma) 70 80 90 Elecfro!fsm Across Two Chromium (53-47 mole %) Melt 1.2 1.4 1.6 1.8 4 TPK) 2.0 2.2 2.4 2.6 X 403 0.40 \\\\\\\\\\ \\ T NS DR = 5 E et !!\\ ___.——-":—_— \ A "~ = \\\\\\\\\ ™~ THEORETICAL 0.06 0.04 ' 0.02 > 0 550 600 650 700 750 800 TEMPERATURE (°C) Fig. 4.4. Theoretical and Experimental EMF Values for Cells of Type 2 at Various Temperatures. - ‘ . UNCELASSIFIED . UNCLASSIFIED ORNL-LR-DWG 9183 ORNL—LR—DWG 9434 360 320 3 280 @ POINTS TAKEN IN INITIAL RUN e o - O POINTS TAKEN AFTER REVERSAL OF L * CURRENT ' . 240 - . 2 o ~ ¢ R : a . A / L . E 200 /;7 . i W i & - A 3 ca S > Fig. 4.6. Viscosities of the LiNOs-KNos (62.2- 37.8 wt %) Mixture at Various Temperatures. 89 the lowest and highest indices of refraction, re- spectively; 2V refers to the acute angle between the optic axes of biaxial erystals; and O and E " refer to the ordinary and extraordinary indices of ‘refraction of uniaxial crystals. 3L|F' ZrF4 (low=temperature form) - 4.88 3.67 3.43 2.9 2.79 2.67 2.40 2.07 1.94 1.82 1.80 1.78 1.65 1.59 1.57 N © Ny = 1.465 . Biaxial negative; ANP PROJECT PROGRESS REPORT O'pi;icol data: 1.445 a 2V = ~10 deg ,_ Co VV-X-ray data: 549 U 5.40 I/I] 55 35 50 25 6 14 8 15 6 100 19 25 12 12 4 4 4 2LiF-ZrF4 Optical data: 0 1.468 E = 1.478 Uniaxial positive It X-ray data: 10 10 25 100 100 14 11 11 60 2.15 23 2.05 19 1.95 27 1.70 - 31 1.63 | 45 1.58 | 10 1.54 10 3LiF-4ZrF4 : Optical data: N, = 1.463 Ny = 1.473 Biaxial positive; 2y = ™25 deg Xeray data: 0 d(A) /1, 611 | 26 5.24 34 4.90 14 4.21 28 4.00 ' 10 3.90 94 3.77 ' ' 18 3.69 6 3.33 60 3,29 20 3.26 ' 22 3.16 100 2.615 16 2.303 10 2,248 10 2.227 ' 6 2.194 86 2.159 16 2.043 12 2.130 34 1.947 36 1.912 22 1.883 10 1.721 10 2KF « BeF, Optical data: Average refractive index = '[357 Biaxial positive 2v = ~20 deg X-ray data: o d(A) 74 I .).‘.. -y PERIOD ENDING SEPTEMBER 10, 1955 3.24 12 2.292 15 3.14 40 2.220 7 . 3.07 - 8 2.190 4 .J : 2,99 12 | 2.010 35 1. 2.95 37 1.979 23 2.84 100 1.745 7 2.73 18 1.641 10 2.61 20 | 2.58 12 KF+NaF « ZrF 2.465 85 Optical data: . 2,359 | 85 N, = 1.375 2.332 55 Ny = 1.382 2.259 7 Biaxial negative; ¢ 2242 15 2V = ~60 dog 2.184 35 2.159 : 25 ' . Xeray data: 2.106 5 d(A) /1, 2.060 7 5.99 10 2.038 12 5.37 50 . 1.955 12 4.98 16 1.920 12 4.85 60 1.905 10 4.50 50 | ¥ 1.894 8 4.41 6 1.854 12 4.25 30 . 1.815 15 4.09 64 e 1.736 15 3.69 28 1.708 | 35 3.60 12 . 1.657 7 3.52 6 1.641 7 3.34 100 3.26 44 KF:BeF, 3.18 40 Optical data: 3.12 12 Average refractive index = 1,315 3.07 12 z Biaxial positive; 3.01 38 2y =~60deg S 2.747 | 4 B -‘.-X;m.y dm . : e 2,690 24 3 N : 2.556 20 - - dA o v 2.489 24 Tess o s | 2405 | 20 599 60 o 2.258 20 L ogee P 2154 1 358 T T e 225 20 333 90 ' 2.050 o 34 3.23 35 1.947 20 3.01 100 1.928 12 2.92 6 1.886 12 S 21 1792 14 | 263 200 0 L743 8 | 2.542 5 ' 1.723 14 2.442 5 1.694 6 2.410 7 1.651 24 91 T R I T T T 'ANP PROJECT PROGRESS REFORT ' _— ~ 3KF«3NaF «2ZF 3.78 . S ' E i S T S " Optical data: | | 3.74 | VE ; N D L | 2;192 :3 : N) = 1.422 : 1} , " Biaxial positive; 3.36 62 * T2V = ™30 deg 2.630 13 e R - | 2.074 .75 ... . Xeray data: _ 1.935 12 d(z) v 1.766 52 VX I 17 1.506 | 25 : 490 | 100 | o : 4.82 25 2NaF+LiF «2BeF, = B 455 . 15 Optical data: _ . ' 4.'27 , 33 Average refractive index = 1.312 7.4'09 75 Uniaxial negative; 3,'78 : , 12 Low birefringence 3,40 21 | . - 3.28 | 21 . X-tay datat 2,99 21 d(A) | Vi, Con297 88 5.37 24 T | e 12 4.07 15 | | e 12 378 n , S e 585 6 3.57 18 "y a_ 2,455 - 25 3.39 21 | 1 2.417 21 3.08 7 ) ‘. 2.368 12 2.99 100 2,270 25 2.614 12 | ' " 2,226 52 2 417 15 ' = < 2,135 42 2.343 57 b - 2.051 49 2.303 07 1,931 15 0.240 20 1.822 42 2.707 ‘ ‘ 1.748 21 2.149 26 - 1.721 25 9111 o . ‘ ' 2.039 ' 7 ' 3NaF - 4ZrF 1.999 6 b Optical data: 1.968 ' 100 o N, = 1.420 1.928 9 ' Ny = 1.432 1.894 10 . Biaxial poéifive,‘ 1.840 30 oy =30 deg 1.790 19 _ x-roy data: 1.767 4 e 1.748 7 - dlA) /1 1.720 19 7.5 - 1.704 s 7.42 ” 45 1.676 ' e 547 14 1.612 | 12 4,15 ' 100 1.589 e High-Temperature X-Ray Spectrometer Studies G. D. White, Metallurgy Division * T. N. McVay, ansultaht by ’ Samples of 3LiF.ZrF, were x-rayed at elevated ' temperatures by using the furnace attachment to the x-ray spectrometer. The investigation was conducted to confirm the decomposition tempera- ture of Li,ZrF,, which had already been deter- mined by quench methods and thermal data, and also to determine whether there was a high- temperature polymorph of Li,ZrF, that was not retained when the material was quenched. At room ’remperai’ure the samples contained three phases: Li ,ZrF g, LigZrF,, and LiF. In this study the procedure qu to heat the mounted sample in the evacuated furnace attachment to 550°C and then maintain it at that temperature ~ until the x-ray diffraction pattern contained none . - ofthe Li2sz6 or LiF peaks. The reacted sample o was then cooled to various temperatures until the x-ray pattern mdlcated the presence of Li ZrF andLiF. In this manner ’rhe decomposition temperq- ture was deTermmed as being 470°C, which is to be compared with the value of approximately S sl 475°C obtained by quench methods, At no tem- _ perature above 470°C was the x-ray pattern for . the low-temperature form of Li,ZrF, obtained. The high-temperature x-ray pattern, presented be- low, is evidently the pattern for a polymorph of Li,ZrF,, which inverts to the lower temperature form at a temperature just slightly above the de- compos ition temperature: | h aw g 59 Physical Chemlstry of Fused Sults e g - E - . . Final results have been obtamed for the elec- trical conductance and density of all molten alkali chlorides, bromides, and iodides. The equivalent . R. ,VGn:A‘rfsda]eh” - Chemlsfry Dlvnsuon PERIOD ENDING SEPTEMBER 10, 1955 conductance at corresponding temperatures has been correlated with such properties as ion size and mass. Conductance has been treated as a rate process, and values of the heat of activation and entropy of activation have been computed from experimental data. In general, the heat of activation is somewhat temperature dependent; this dependence is approximately linear for lithium, sodium, and potassium salts, while it deviates progressively more from linearity with rubidium and cesium salts. The entropy of activation for these salts is in the range of —6 to —8 eu. This small negative entropy of activation is reason- able and indicates a similar conduction mechanism for all the salts, but no detailed quantitative significance can be attached to it at this time. An extensive series of freezing-point-depression measurements has been made in which molten sodium nitrate was the solvent, The heavy-metal halides CdCl,, ZnCl,, CuCl,, PbCIz, and CdBr, all show less than complete ionic dlssocmhon in molten sodium nitrate; dissociation decreases as conceniration rises. However, the slopes of the curves indicate complete dissociation at infinite dilution, The significant discovery has been made that the scecalled ‘““common ion effect’’ is generally applicable to these salts. Thus the addition of any of a large number of completely dissociated chlorides greatly represses ionic dissociation of partially dissociated chlerides such as PbCl, and CdCl,. It has been demonstrated in the case of CdCl, that the complex ion CdCl, ™~ is formed in the presence of relatively low con- " centrations of excess common chloride ion. Re- ___actions have been proposed to account for the ““results, and equilibrium constants have been cal- ‘ culated. Apparently those chlorocadmium com- plexes containing even numbers of chlorines are the more stable. —~Several preliminary measurements have been .- made of freezing-point depression by K2Zr|:6 and Kz'i'iF‘5 in NaNO3. The salts were prepared by ~ wet chemical methods. The results indicate that the complex ions ZrF ;== and TiF ;=7 are reason- ’ably ‘'stable ‘at a concentration of about 0.1 molal .. _in_molten NaNQ, at its melting point. However, _,___H_‘Gthere appears to be some slight dissociation, :_whlch presumably ylelds F~ and ZrF or TiF,~ ‘Dissociation is greater with htanlum than wH'h 31Details of this work will be published in separate reports and articles by the ORNL Chemistry Division, 93 " ANP PROJECT PROGRESS REPORT ~zirconium, A similar result was obtained pre- _fvnously with K ZrF‘S prepared by a dry fusion F’reC|se determlnctlons of the self-diffusion co- 7,_'jeffl<:|en'rs of sodium ion and of nitrate ion have “been completed in molten sodium nitrate, A radlo- chemical frccer technique employing Na?? was used for Na*, and a mass spectrographic tracer technlque employing O'® was used for NO, ™. The self-diffusion coefficients are expressed with- in 1 to 2% by 'rhe fo”owmg equahons 1.288 x 10=3 (A9TO/RT ‘Il" D+ 8974 x 104 o=5083/RT .~ThIS is the flrsf 'rlme ’that self-dn‘fusmn of both ""flons of a smgle fused salt has been measured, g ft is highly significant that the heats of activa- - tion for 's}elf-vdkiffdsion of both the cation and the anion ore ‘the same within experlmental error - ("-'80 cul) Thls indicates that there is a single - frictional coefflment for diffusion within the melt. The resu[fs show that the simple Nernst-Einstein equation is inapplicable to this molten salt; it s probably not applicable to any molten salt. " The ratio of self-diffusion coefficients for Na¥ ~and NO,~ is somewhat less than the inverse ratio - of the square roots of the masses of the two ions, It is expected that both mass and size are im- ‘portant factors in determining diffusion, Experi- ments are in progress with other fused salts, and ~attempts will be made to obtain generalizations “concerning diffusional properties. Diffraction Studies ofnL.icjb'i'dér P. C. Sharrah P, Agron H. A, Levy M. Danford M. A, Bredig Chemistry Division The previously described32:33 liquid diffrac- tometer has been thoroughly aligned and tested and is being applied to studies of molten salts, X-ray diffraction patterns obtained from liquid mercury at room temperature were used to test the instrument; the pattcrns were satisfactory. These diffraction patterns and the analysis giving in- formation concerning the distribution of atoms within the liquid have been presented, 33 It has been possible to obtain data which appear to be reliable to a somewhat larger value of the variable = (47 sin 6)/A than that reported in the litera- ture. Work is under way with molten lithium chloride. | Neutron diffraction work on molten salts is also being carried on so that information from the two technlques can be coordinated. The equnpmem‘34 consists of the” Chemistry Division neutron spec- trometer and a furnace for handling the molten materials., Diffraction patterns of KCI and Li7l have been obtained. 32p, C. Sharrah et al., ANP Quar. Prog. Rep, June 10, 1955. ORNL.-1896, p 81. Cbem. Semiann, Prog. Rep. June 20, 1955, ORNL- 1940 (in press). 34P. C. Sharrah and G. P. Smith, J. Chem Phys. 21, 228 (1953). - “with sodlum-pota PERIOD ENDING SEPTEMBER 10, 1955 5. CORROSION RESEARCH W. D. Manly G. M. Adamson Metallurgy Division W. R. Grimes F. Kertesz Materials Chemistry Division Several Inconel forced-circulation loops that were operated with fluoride mixtures and with sodium as the circulated fluids were examined. The effect of operating time on corrosion and mass transfer under the dynamic conditions was studied for loops that circulated NaF-ZrF -UF , as well as the effects of the method of heating the loop and of the length of the heated section, The loops in which sodium was circulated were used to study the effects on mass transfer of varying the temperature differential in the system and of varying the oxide content of the sodium and were used to compare mass fransfer in Inconel and in type 316 stainless steel, Additional Inconel thermal-convection loops were examined to determine the effects on cor- rosion and mass transfer, in loops that circulated fluoride mixtures, of varying the loop cleaning method, of using direct resistance heating, and of applying electromotive forces. In one loop, the wall temperatures in the heated zone were measured, The effects of oxide additions were studied in loops that circulated sodium. Several hot-pressed metal-bonded tungsten carbide cermets were screen tested in NaF-ZrF -UF and in sodium, and additional solid-phase bonding tests of cermets were made, Inconel plc'red with ’ruthenlum was sub|ec’red to cree-p-rupfure fes’rs,_ - and oddmonal tesfs of brazed T-joints in fluoride f'mleures and in sodlum Were made. A Hastelloy | "",B—Inconel system was “checked for dlSSlmllar- L metal mass fransfer in a fluoride. mleure. / ¢ A study of mass transfer in an Inconel sys’rem‘ ' _'__"‘;‘cwculahng “sodium was initiated, - corrosion tests wer and seesaw ----- tic hthlum._ spectra in fused hydroxides at high temperatures, mass transfer and corrosion in fused hydroxides, and thermal dissociation of sodium hydroxide, ¢ made on Inconel tubes loaded -lithiom mixtures. In other icorrosnon tests molybdenum, vanadium, and niobium ' '""ff'were fes e_d A " The >furri'domen16| corrosion research repon‘ed included additional s’rudles of fiim formchon on metals, techmques for measuring absorphon'w Chemical studies were made of corrosion of Inconel by NaF-LiF-ZrF -UF,, the stability of UF, in NaF-KF-LiF, ang the effect of chromium on 'rhe mass transfer of nickel in NaOH. FORCED-CIRCULATION STUDIES G. M. Adamson R. S. Crouse A, Taboada Metallurgy Division Fluorides in Inconel G. M. Adamson R. S, Crouse Metallurgy Division Examinations were completed of several Inconel forced-circulation loops in which NaF-ZrF ,-UF (50-46-4 mole %) was circulated. The loops anj the operating conditions are described in Sec. 2, ‘‘Experimental Reactor Engineering'’ and in the previous report.! The corrosion data reported in Table 5.1 and the analyses of the fluoride mixtures given in Table 5.2 were for Inconel loops operated with a temperature differential of 200°F, a Reynolds number of the fluoride mixture of 10,000, a maximum fluoride-mixture temperature of 1500°F, and a maximum wall temperature of between 1600 and 1625°F. These loops were heated by direct resistance of the Inconel tubing. Loops 4695-4A, -4B, -4C, -4D-1, and -4D-2 were a single loop in which the two heated legs? were replaced at the end of each experiment. A new batch of fluoride mixture was used for cleaning and operating each test, The loop was cleaned by circulating the fluoride mixture for 2 hr at 1300°F. The loop was then filled for the test with a fresh batch of fluoride mixture, which was circulated iscthermally for 25 hr before the temperature differential was applied. ~The period of isothermal operation was for the purpose of establishing chemical equilibrium, 16. M. Adamson and R. S. Crouse, ANP Quar, Prog. Rep. June 10, 1955, ORNL-1896, p 83. 2For experimental arrangement see Fig. 5.2, p 86, of the previous report (ORNL~1896). 95 PR T O v T T TR T TR T st RS S s granular voids to a depth of 5 mils ANP PROJECT PROGRESS REPORT TABLE 5.1, EFFECT OF OPERATlNG T|ME ON DEPTH OF ATTACK IN |NCONEL FORCED-ClRCULATION LOOPS IN WHICH NoF-ZrF -UF (50-46 -4 mole %) WAS CIRCULATED Operating ‘Loop . " Ne Time Attack of First Heated Leg Attack of Second Heated Leg ' (hr) 4695-4A 0 | Light, general, subsurfaice voids to Light, genercxl,r uii"ét‘granular subsurface : S voids to a depth of 0.5 mil . vonds to a depfh of 0.5 mil 3 -5A - 10 Heavy, genet"a.l voids to .0. .débfh of Heavy, eneral voids to a depfh of - 3.5 mils _3m|{$_ 3 -4D-1 ~20.’5' ' Herovy,'gene;al;r i:r;fefgfdnfiiaf voids ‘Hercl.v'y, general, ‘|'n"re|.;g'rr;:'lAn;Jlla'r voids toa i L to a depth of 3 mils depth of 3 mils 4 -4B 50 Heavy, generc;l voids to a depth of Heavy, general v0|ds to a depth of 3 3 mils _ 3 mils - =4C 100 Heavy, general voids to a depth of Heavy, general vo'ids‘fo'a:clepth of 3 mils 3.5 mils | | 3 -SB 241 Heavy, general, intergranular voids Heavy; general, lnf:ergfdnblaf voids to a o ' o to a depth of 4 mils depfh of 5 mxls '.»,-4D'-2 ' 500 Moderate to lighf, general, inter- Moderofe, eneral, mtergranulur volds o e : granular voids to a depth of to a depth of 5 mils 3n5 mils ;-5C-_2 1000 Moderate to heavy, general, inter- Moderate to heavy, general, intergranuiar voids to a depth of 7 mils *Time after temperature differential imposed. TABLE 5.2, ANALYSES OF FLUORIDE MIXTURES BEFORE AND AFTER CIRCULATICN IN LOOPS 'Aft‘ér termination Uranium ‘s _ Impurities (ppm) Loop No. When Sampled Content - (wt %) Ni Cr Fe 4695-4A During filling 8.36 6 70 70 | After termination 8.26 9 245 30 -5A During filling 8.71 15 70 45 After termination 8.77 25 635 30 -4D During filling 8.46 15 65 40 _ After termination 8.57 40 520 50 -4B During filling 8.80 50 65 | 30 After termination 8.85 10 800 25 -4C During filling 8.33 15 35 20 o After termination 8.84 8 725 50 -5B During filling 8.94 7 60 30 After first termination 9.15 20 ' 765 , * 50" ‘ o o After Seéond termination 8.95 30 725 75 . -4D-2 During filling 8.83 30 90 10 Cee After termination 9.14 55 365(?) 70 . -5C-2 ~ During filling 9.12 5 105 60 e 9.15 56 505 45 s it Skl e L Gk - Sekil the depfh of a'rtacrk and the ch were still qun‘e low, Durmg fhe ubsequent first few hours of operdtion with a temperature dlffer- ential and a high waH temperm‘ure, the attack was quite rapid, with more a’rtuck bemg found after the first 10 hr of opercmon thcn had prev:ously' occutred in 25 hr of isothermal operation. After the first 50 hr fhe chromrum contenf of the fluoride mixture remcmed constant, bu’r the depfh of attack increased, in conflrmohon of the thermai-con- vechon-loop data on mass transfer. Considerable scatter is present in the data, but a depth of attack of between 3 and 4 mils per 1000 hr of circulation seems to be a reasonable value for the second stage of attack. Typical hot-leq sections from these loops are shown in Flg. 3.1, Two “other loops (4950 2 “and_ 4935- 2) wefe operated in as nearly ‘an’ Jdenhcal manner as‘v‘ possible, except that one was heated in a gas furnace and the other was heated by the direct electrical res:stance of the pipe wall, Both loops were operated for 1000 hr, with NaF- ZrF4 UF (50-46-4 mole %) as the cwculcfed fluid, a temper- ature differential of 200°F, a maximum fluoride temperature of 1500°F, and a fluorlde-mleure Reynolds number of 5000. In both |<:ops a moderate concentration of subsurface ‘voids to a max1mum depth of 5 mils was found. A typical area from the electrically heated loop |s shown in Fig. 5.2. These loops had 17-ft-long heated sections to keep the wall temperatures down c:nd to show that PERIOD ENDING SEPTEMBER 10, 1955 dn‘ferenthl condn‘no s, it _ increase fhe powe p _run:t of heq ,e'f 'engfh whlch resulted in a 100°F mcrease in wall temperature, This loop showed heavy ‘subsurface-void attack to a depth of 18 mils. These data are additional evidence that the wall temperature is a more critical variable than is the fluoride-mixture térfiperaturé. A series of loops with varying, but contro“ed wall temperatures are now being operated. Sodium in Inconel and in Stainless Steel G. M. Adamson A, Tabeoada Metallurgy Division Two Inconel forced-circulation loops (49512 and 4951-3) in which sodium was circulated were examined after operating for 500 hr with a hot-leg temperature of 1500°F. Loop 4951-2 had a 300°F temperature differential, and loop 4951-3 had a - 150°F temperature differential. The two loops were of a test series which included loop 4951-1, operated previously, which had a temperature differential of 200°F Table 5.3 presents the metallographic and chemical dota obtained in this series of tests. No correlation can be observed between the amount of mass transfer and the temperature ‘differential. However, the three loops were not identical, and high oxide impurities of different amounts were found in these loops. The results of these differences could have obscured the effects of the different temperature differentials. d gLrpulahon Ioops were n 0.5 450 s us 240 97 ANP PROJECT PROGRESS REPORT - i e P o - . 100 hr _ 241 hr Ll 500 hr 1000 hr " Fig. 5.1. Chdnges in Attack with Increasing Operating Time in Forced-Circulation Inconel Loops. i Fluorlde mleure circulated, NaF- ZrfF, UF (50-46-4 mole %); maximum fluoride-mixture temperature, ]500°F temperature differential, 200°F f[uorlde-mleure Reynolds number, 5000. S hot-leg temperature of 1500°F, o temperature difference of 300°F, and a Reynolds number of 15,000, This loop showed the maximum mass transfer found to date, There was a 30-mil-thick deposit in the economizer, and there was attack to a depth of 2 mils in the hot leg. Three sections from the economizer and one from the cold leg are shown in Fig. 5.3. The second loop, 4951-6, which was operated for 1000 hr, included a bypass cold trap for removing oxides. The hot-leg temperature was 1500°F, and the temperature differential was 300°F Metallographic examination showed mass-trans- ferred deposits to a maximum thickness of 11 mils (Figs. 5.4 and 5.5), which is comparable with the thickness of the deposits found in the loop with no cold trap. There was attack in the hot leg to a depth of 1.5 mils (Fig. 5.6) that was of the intergranular type found previously in sodium- Inconel systems., Analyses of the sodium after operation of the loop showed from 150 to 290 ppm O,, and thus very’ little of the oxide had been removed, In an effort to obtain a more qualitative picture of the amount of mass transfer in the sodium loops, all the sodium was melted out and the mum fluorlde-mleure temperature, 1500°F; tempera- ture differential, 200°F; fluoride-mixture Reynolds number, 5000. : __jFié. 5 2, Typicul Attack in Direct-Resistance-- " Heated Leg of Inconel Forced-Clrculuhon Loop - (4950-2) Operoted for 1000 hr. “Fluoride mlxture'i'\ - circulated, NaF-ZrF UF4 (50-46-4 mole %); maxi- PERIOD ENDING SEPTEMBER I‘O, 1955 deposited metallic crystals were brushed out and weighed, With this procedure, any well-bonded crystals or layers were left in the loop. The data thus obtained from the loops operated to date are presented in Table 5.4, Operation of the type 316 stainless steel loop (4951-7) listed in Table 5.4 was terminated by a power failure after sodium had been circulated for 476 hr. There was no oxide filter used in this loop. It was the third loop operated in a series of tests; the other two loops (4689-5 and -6) were Inconel with type 316 stainless steel cold legs., Loops 4689-5 and «6 operated for 1000 hr under similar temperature conditions, The maximum thickness of the mass-transferred layer in the UNCLASSIFIED T-8097 HONI ECONOMIZER SECTIONS 5.3. Three Sec‘l'loi»'ls-‘-f'q-fbm_'fhe Economizer Fig. “and One Section fiéifi'n‘tl"ié"”'C-o'iawLeé “of Inconel Forced Clrculuhon Loop 4951.5 Which Circulated for 1000 hr Sodium to Which 0.15% 0, Had Been Added as Na,0,. Hot-leg femperature, 1500°F; temperature differential, 300°F; Reynolds number, 15,000. 99 e o b e ety ANP PROJECT PROGRESS REPORT UNCLASSIFIED -7?46 COLD-LEG SECTION ECONOMIZER SECTIONS Fig. 5.4. Three Sections from the Economizer and One Section from the Cold Leg of Inconel Forced-Circulation Loop 4951.6 Which Included a Bypass Cold Trap and Which Circulated High- Purity Sodium for 1000 hr. Hot-leg temperature, 1500°F; temperature differential, 300°F; Reynolds number, 15,000. all-stamless-steel loop (495] 7) was 0.8 mil ,_'-(Flg. 57), which is much less than the 9 mils “found in Inconel-and-sfclnless-steel loops (4689-5 ‘and -6). Two different layers were present in the “all-stainless-steel loop. The majority of the deposited material was in the economizer, and it was found by chemical analysis to be 14.9% Ni, 57.5% Cr, and 20. 0% Fe. The second layer was f_-'j',}llmifed to the electromagnetic flowmeter area in *;;the cold Ieg, and it was a smooth, adherent “deposit that was found by chemical analysis to be - 146% Nl, 19._]%_ Cr, and 55.2% Fe. i00 Fig. 5.5. 1000 hr. 250X. Reduced 34%. Fig. 5.6. Typical Hot-Leg Attack in Loop 4951-6. 250X. Reduced 33%. THERMAL.- CONVECTION STUDIES G. M. Adamson E. A. Kovacewch Metallurgy Division T. C. Price Pratt & Whitney Aircraft Effect of Various Loop Cleaning Methods The standard procedure for cieahingnlh‘c'dhelw“ thermal-convection loops has been the prehmmary circulation of a fluoride mixture for 2 hr with the system isothermal at 1350°F, The cleaning was undertaken to assure correlation of data between loops; it was not expected to decrease corrosive Deposited Layer in Economizer of ‘Inconel Loop 4951-6 Which Circulated Sodium for ~y o B, B N kbl . BARRIR. PERIOD ENDING SEPTEMBER 10, 1955 TABLE 5.4, WEIGHTS OF DEPOSITED LAYERS IN VARIOUS LOOPS WHICH CIRCULATED SODIUM Oxide Content (wt %) l.oop I .W;igi-wt"of 'Deposit Maximum Layer Thickness Difference from Control Loop ] Before After No. (9) (mils) Operation Operation 49511 200°F temperature 7.9 1 0.034 0.046 differential ' ' -3 150°F temperature 9.0 8 0.031 0.024 ' - differential - S e s | 0.021 -5 Oxide added, operated 25.8 30 0.036 0.027 1000 hr =6 Bypass cold trop in 7.6 11 e 0.041 0.017 7 Type 316 stainless 08 1 0.087 0.04 Lo s'ree_lrtt_:ubing 7 *Inconel loop operated for 500 hr; temperature differential 15,000. ' attack during experiments. Over the past few mdnfhs,'“hb’wléver",' th‘e"'ddt& obtained have not been S0 reproduc:ble as those obtained prevnously. To determme whether the clecmmg operation was respon51ble for this lack of reproducrblllty, a series of Inconel loops that had been clecmed by ‘various me'rhods were operatecl for 250 br with NaF- ZrF4 UF4 (50-46-4 mole %) as fhe “circulated f_l;u_d The data from these loops ure ‘presented in u,\ o , ifiréwously fOUl‘Id‘ The:resulfs DV RS the ¢ K __M. caflef of the results being obtal‘hed with stancfard, |oops. ‘ ;:These Ioopswall operated ‘with c“stcndurd hot-legjt temperature of 1500°F, and they circulated | i\']dF-Zer'-UF:'4 (50-46-4 mole %). Loop 618 " that the wall ‘temperatures under the heaters may , 300°F; hot-leg tempéroturé; 1500°F; Reynolds number, showed the usual subsurface-void type of attack to a depth of 10 mils after 500 hr, while loops 619 and 703 showed similar attack to depths of 13 and 15 mils after 1000 hr. These depths of attack are similar to those obtained in the loops with the - clamshell heaters, and thus the previous conclusion ’rhatljthe depfh ‘of attack is not affected by the hea ng. method |s conflrmed it was shown in 'rhe forced-cn‘culahon 1oops that the maximum loop wall temperature was a more lmpor'ranf vorldble than was the max1mum depth of “attack found in recently operated forced-' . han_that found o c:rculahon Ioops has been less be as much as 1670°F. This 170°F differential from the 1500°F bulk-fluoride-mixture temperature 101 _ally ‘measured by a y hof Ieg abouf Jin, T T | TTT Ree “ANP PROJECT PROGRESS REPORT el uNCLAssmED] T- 8062 COLD-LEG SECTION ECONOMIZER SECTIONS Fig. 5.7. Three Sections from the Economizer and One Section from the Cold Leg of Type 316 Stainless Steel Loop 4951.7 Which Circulated Sodium for 476 hr. Hot-leg temperature, 1500°F; temperature differential, 300°F; Reynolds number, 15,000. would be éhbugh to explain the greater depths of afiack Effecf of Apphed Electromotive Forces A series ‘of thermal-convection loops ‘were operated with small applied potentials to determine _whether the corrosion mechanism is electro- chemical in ncture and at the same time, to ""determlne whether any deleterious effects would rbe found wnth sfray currents, Wires were attached “to the hot and cold legs of a loop, and a potential /fwas Opplled by a bcn‘tery charger. The current i "How was small, averaging only 5 amp at 1 v. "'_'_’All these Ioops were fabrlcafed of Inconel, and TABLE 5.5. EFFECT OF LOOP CLEANING METHOD ON DEPTH OF ATTACK Ldop A Maximum Attack No. Method of Cleaning C (miis) 725 Fluoride mixture _ 8 | 726 Fluoride mixture 7 8 722 Nitric ond hydrofluoric 8 acids 737 Nitric and hydrofluoric 8 acids 723 Dry hydrogen 9 724 Dry hydrogen 8 727 No cleaning 7 728 No cleaning 7 732 Layer machined from 7 inner wall they circulated NaF-ZrF ,-UF, (50-46-4 m.o[e %) at 1500°F. Results of some of the short-time tests were reported previously, but the data are. repeated here to present a complete summary, The_ data from the completed series of ‘tests are presented in Table 5.6. The loop that was operated for 2000 hr with a positive charge applied to the hot Ieg showed only about one-half the depth of attack found in the loop operated with a negative charge cpplied to the hot leg. With a negative hot leg, the depth of attack was about the same as that found the control loop with no applied potenfial From these few data, it does not appear that small s'rray pofem‘ials will increase the attack. Alfhough B it would be difficult to apply a potential in'a system as complicated as a reactor, it appears' that it would be possible to reduce the attack by applying a positive potential. Effect of Oxide Additions to Sodlum A series of Inconel thermal-convectlon |oop5m was operated with varying amounts “of Na 2,0, added to the sodium being C|rcu|cn‘ed ’ro defermme whether mass transfer in the system was. caused ) v by oxide impurities in the sodium. ; : The data obtained, presented in .‘.;Table 5.7, show an increase in mass transfer with increased oxide content. Corresponding lléhg‘thg 7 werecut o T o ¥ .L‘ PERIOD ENDING SEPTEMBER 10, 1955 TABLE 5.6, EFFECT OF APPLIED POTENTIAL ON DEPTH OF ATTACK IN THERMAL-CONVECTION - LOOPS WHICH CIRCULATED NaF-ZrF -UF4 (50-46-4 mole %) L ol Eluorid Time of Final Chromium Maximum o Originat Fluoride Hot-Leg Charge Operation Concentration Attack Intensity of Attack No. Mixture Batch No. . _ ' (hr) (ppm) (mils) 540 188 PF-1 None 500 520 |8 Moderate to heavy {control) 541 188 PF-1 Positive 500 550 7.5 Heavy 542 188 PF-7 Negative 500 675 7 Heavy 554 188 PF-7 Nore - 500 635 11 Moderate to heavy (control) - 614 248 PF-4 None 1000 875 15 Heavy (control) ' 615 248 PF-4 Positive 1500 720 12 Heavy 616 248 PF-4 Nggaflve 1500 1200 20 Heavy 617 248 PF-4 None 2000 950 19 Moderate to heavy (control) 552 217 PF-5 Positive 2000 610 7 Moderate to heavy 553 217 PF-5 | Negative 2000 740 15 Moderate to heavy TABLE 5.7. MASS TRANS FER IN INCONEL THERMAL-CONVECTION L.GOPS WHICH . CIRCULATED SODIUM WITH ADDITIONS OF N0202 Loop N0202 Added Operating Time Hot-Leg Attack Relative Mass No. (wt %) (hr) (mils) Transfer* 729 ' ane 500 1.5 Trace 70 Nene o s10% s Trace 731 “Neme 2000 | 0.06 ' o 432**"" 2 Trace e T 1000 R 2 0.03 ‘ “0\-2/“ Ten e 3]3** S o 2 0.04 o2 ’"'1000_'_( '3 0.05 500 ‘ 3 ' 0.02 S8 05 w0 3 ~0as *R elative figures obtained by weighing the metal removed from a known length of the horizontal hot leg and con- verting the value obtained to an average weight per inch, **T erminated by leak. 103 "ANP PROJECT PROGRESS REPORT from the lower vertical cold leg and the horizontal hot leg of each loop. The deposit in each section was brushed out and weighed, and the weight value was converted to an average weight per _inch, These values, given in Table 5.7, are ‘relative and subject to considerable error. They do show, however, increased mass transfer with increased oxide content. | The increased mass transfer was also reflected in increased otfock in the hot legs. The depths of attack varled from 1.5 mils in the control loops ‘to 4 mils in the high-oxide-content loops. The cfl’ack was primarily intergranular, with, possibly, some general surface removal. Some difficulty was encountered with the loop supports during _this series of tests, and operation of several - loops had to be terminated because of leaks. 'VThIS dlffaculty now appears to have been corrected. GENERAL CORROSION STUDIES ' E. E. Hoffman W. H. Cook | C. F. Leitten, Jr, Metallurgy Division R, Carlander Pratt & Whitney Aircraft Hot-Pressed ietal-Bonded Tungsten Carbide in NaF-ZrF ,-UF W. H. Cook | Metallurgy Division Several Haynes Stellite Company, experimental, hot-pressed, metal-bonded, tungsten carbide specimens have been screen tested in NaF- ZrF UF (53. 5-40-6.5 mole %) and in sodlum in the seesaw apparatus at 4.25 cpm. were at 1500 and 1200°F, respectively, Each specimen was held in the hot zone of its capsule during the 200-hr test period. The nominal compositions of the materials tested are given in Table 5.8. Metallographic examination of the untested and tested specimens did not reveal any measurable attack on any of the tested specimens. It did show that the structure was, in general, good, The tungsten carbide particles were small, and the specimens had little porosity, The tungsten carbide and metal distributions were good, with the exception that there were small isles of metal that was free of tungsten carbide particles in all specimens, These isles were few and small in the specimens that had more than 20% metal. Typical untested and tested 88% tungsten carbide— 12% Hastelloy C specimens are shown in Fig. 5.8, Solid-Phase Bonding of Cermets W. H. Cook Metallurgy Division Recheck tests have been made on several cermet pairs in order to evaluate better the solld-phase bondmg results obtained in previous screening tests,> The cermets tested were manufactured by Kennametal, Inc., under the trade name Kentanium. The results of the recheck, given in Table 5.9, are the same as those obtained in the previous tests, 3E. E. Hoffman, W. H. Cook, and C. F. Leitten, Jr., ANP Quar, Prog. Rep. June 10, 1955, ORNL-1896, p 96. '_TABL'E 5,8, NOMINAL COMPOSITIONS OF SEVERAL EXPERIMENTAL, HOT-PRESSED, Ll TUNGSTEN CARBIDE CERMETS ' Nominal Compesition (wt %) - A?im'l Brin’der . wC Co Ni Cr Mo W _ Fq . C - ,Hasfenoy c 88 6.8 2.0 2.1 0.5 o 7002 - Haynes Alloy No. 31 88 67 13 3 09 o 2 Toes 90% Co-10%Cr 84 14.4 1.6 I "Haynes Alloy No. 6 84 10.3 4.4 0.6 05 06 Haynes Alloy No. 6 76 15.5 6.6 10 07 024 " Haynes Alloy No. 6-8% Co 80 15.7 3.3 05 04 000 " Haynes Alloy No. 6-12% Co 76 19.7 3.3 0.5 04 000 104 The hot anci cold Jzon-es | oL DR PERIOD ENDING SEPTEMBER 10, 1955 UNCL ASS?F]ED Y- 15450 4 3 % oy ] Fig. 5.8, (a) The 88% Tung.'sten Curbi&e—"lZ%r Hastelloy C Cermet Before VTesfing. (b) The Same ic ' Specimen After Exposure for 200 hr to NaF-ZrF -UF , (53.5-40-6.5 mole %) in the 1500°F Hot Zone of ' a Seesaw Apparatus in Which the Cold Zone Was at 1200°F. Specimens unetched. 1000X. Reduced 2%. TABLE 5.9. RESULTS OF RECHECK TESTS OF 'SQLID-P‘HA‘SE‘BONDING OF SEVERAL CERMETS EXPOSED TO NaoF-ZtF 4-1.;‘|=4 (53.5-40-6.5 male %)' AT 1500°F FOR 100 hr AT 50,000 psi* Composlhons. K]50A (80 wt % TIC 'IO wf % NbTaTIC ~10 wt % NI) . . g el KISIA (70 wt % TIC 10 wt % NbTaTnC ..20 wt % Ni) ]5?8 (64 wf % TlC-—6 wf % NbTaTlC -30 wt % N.) * K]é?B (64 wf % T|C~—6 wi % NbTuTIC -25 wt % Nl--5 wt % Mo) L K150A vs K152 D | Some : 7 KISIAwsKIS2B " Nonme KisBvskie2B " Nome . K162B vs ‘ - T Some *Cale u'[_ar'rea ccnta ct lp}ess't;rfié.' ' \ i ' 105 - ANP PROJECT PROGRESS REPORT Further evaluuhon of fhe best of the nonbondmg cermefs, as determlned by the original and re- checkmg tests, will be made in solid-phase 'bondlng tests of these materials in the form of valve disks and seats, It is planned to study the resistance to sohd-phase bonding for long periods ~ of time, 1000 hr or more; the effects, if any, of “braze-joining the cermets to Inconel (cf. Sec. 6, “‘Metallurgy and Ceramics’); and, possibly, the o effec’rs of repeofed seahngs of fhe dlsks und seats, Effects of Ruihemum on Physncul PrOperhes of lnconel “C.F. Lelh‘en, Jr. MetaHurgy Dlv:smn Slnce the examlnanons of vorlous sechons of ‘the ARE4 and the LITR fluoride-fuel loop5 revealed slight deposits of ruthenium metal on the walls of the Inconel tubes, the effect of ruthenium on the physical properties of Inconel is being studied. A thin layer of ruthenium metal was electrodeposited from a solution of ruthenium nitrosochloride on an Inconel creep-test specimen, The thickness of the ruthenium plate on the Inconel was approximately 1.5 mils. The plated creep-test specimen was annealed in an evacuated Inconel capsule for 100 hr at 1500°F to allow the ruthenium to diffuse into the specimen. The specu'nen was then glven a creep-rupfure test in a purified argon atmosphere at a stress of 3500 psi. In calculating the stress, the area of the ruthenium plate was included. The results of the creep- rupture tests on the ruthenium-plated Inconel and on an unplated, standard, Inconel specimen are presented in Table 5.10, Since a difference in rupture times was found, another test is now in progress to check the results, A metallographic examination of the strained portions of the ruptured rutheniumeplated Inconel specimen showed no difference in microstructure in comparison with that of a ruptured, unplated, Inconel specimen (Fig. 5.9). Creep-rupture tests ~are also to be conducted on ruthenium-plated Inconel specimens in the fused-salt mixtures, S 4M. T. Robmson, S A. Reynolds, and H, W, Wr:ght, ANP Quar, Prog. Rep. Mar. 10, 1955, ORNL-1864, p 14. SM. T. Robmson cmd T H. Handley, ANP Quar Prog. o Rep ]une 10, 1955, ORNL-1896, p 167. i " TABLE 5.10. COMPARISON OF CREEP-RUPTURE DATA ON RUTHENIUM-PLATED AND o UNPLATEDINCONEL ‘ ' Stress: 3500 psi Test temperature: 1500°F Test environment: Argon Time to Final Creep Specimen Rupture Elongation Rate o () L) (%/hr) Plated 873 13 00145 Unplated 1467 12 0.0028 Brazing Alloys on Inconel and on Nickel in -Sodium and in NaF-ZrF4-UF4 C. F. Leitten, Jr. Metallurgy Division Seesaw tests have been completed on a series of brazing alloys on Inconel T-joints. These tests were conducted in sodium and in the fuel mixture NaF- ZrF -UF, (53.5-40-6.5 mole %) for 100 hr at a hot-zone temperai‘ure of 1500°F. A temperature differential of approximately 400°F was maintained between the hot and cold zones of the test container, The data obtained from weight measurements and metallographic ex- amination of the tested T-joints are given in Table 5.11. The 82% Au-18% Ni brazing alloy and copper were tested only in the fuel mixture, because previous corrosion data had indicated the poor corrosion resistance of these alloys in sodium, The seesaw test on the Coast Metals No. 52 brazing alloy was a retest; the results agree with those previously reported.6 The Coast Metals No. 53 brazing alloy and Electroless nickel showed good corrosionresistance to both mediums, as indicated in Table 5.11. The Inconel T-joints brazed with Coast Metals alloy No. 53 are shown in Fig. 5.10 after exposure to the fue! mixture NaF- ZrF UF (53 5-40-6.5 mole %) in a seesaw test for 'IOO hr af a hot-zone tempera- ture of 1500°F and after exposure to sodium under the same conditions. Only slight attack can be seen along the surface of the braze fillet exposed to the fuel mixture; the fillet exposed to sodium showed similar slight surface attack. 6E, E. Hoffman, W. H. Cook, and C. F. Leitten, Jr., ANP Quar, Prog. Rep. June 10, 1955, ORNL-1896, P 98. e " PERIOD ENDING SEPTEMBER 10, 1955 " UNCLASSIFIED o Y-15992 * £ i | The strfiinéd Portions of (a) a Ruthenivm-Plated and (b) an Unplated Inconel Test Specimen Fig. 5.9. Following Rppibrg in o Creep Test. Cathodic etch, 250X, UNCLASSI — 1 . UNCLASSIFIED ¥-1522 o Y-15228 - Flg. 5.10. Inconel T-Joints Brazed with Coast Metals Alloy No. 53 After Seesaw Testing for 100 hr in (a) Fuel Mi‘xturé NOF-Z?F#-UF4 (53.5-40-6.5 mole %) and (b) Sodium at a Hot-Zone Temperature of 1500°F, E’rch.ed'wi'rh aqua regia. 100X. Reduced 20%. 107 Ll iiods ik ANP PROJECT PROGRESS REPORT TABLE 5 11. RESULTS OF SEESAW TESTS OF BRAZED INCONEL T-JOINTS TESTED IN SODIUM AND IN THE FUEL MIXTURE NaF-ZrF, -UF (53.5-40-6.5 mole %) FOR 100 hr ATA 1 - LT HOT-ZONE TEMPERATURE OF 1500°F - . . -'_- o ies Welght Change | - ’7;- Brazing é!loy* Composnhon Bath —m™8 ¥ —— Metallographic Notes b Cwew (9) (%) - Coasf Metals No. 52, Fuel o 0-‘- V Umform surface attack along f1||e1’ to a depth T o 89 Nl-—-5 SI-4 B-—-?. Fe of 0.5 mil _ .Copper ’ Fuel ~0.0602 -—0.026 ‘ Surfoce attack along fillet to a dej;fl'l o? 70.5 mil _ | ' o o Coqst Metals No. 53, Fuel —~0.0011 "-0.092 Nonumform surface attack along f:i!ef To a depth' g S ' 81 Nl—4 5!-4 B 8 T of 1.5 mils ' W E : ’ Erratic attack along surface of f:llef fo a depth 4 ’ c.-_3 Fe Sodium —0.0009 —0.071 of 1 mil No attack along surface of fillet Electroless nickel, Fuel —0.0004 —0.041 90 N:-IO_P“ | Sodium —0.0044 —0.50 _ 'Surface attack along f:llet toa depth of 'I.5 mlls . ©Coast Metals No. NP, Fuel —0.0009 —0.092 Unlform attack along surfuce of hiie'r to a depth ) 50 Ni~12 Si—-28 Fe—4 of 1.5 mils 7 _ _ Mo—4.5 P=1 Mn=0.5 Cr Sodium —0.0069 —0.622 Uniform attack along surface of fillet to a depth of 2.5 mils ' Genera! Electric No. 81, Fuel -0.0008 ~0.067 Attack along surface of braze fillet to o depth of 66 Ni=19 Cr=10 Si—4 3.5 mils . Fe~1 Mn | Soedium —0.0018 —0.0163 Uniform attack along surface of fillet to a depth of 3 mils 82 Au-18 Ni Fuel 0.0011 0.12 Nonuniform attack along fillet to a depth of 4 mils *Brazing alloys listed in order of decreasing corrosion resistance to both test mediums. o G G e e e o L e e e R G ; The Electroless nickel (90% Ni-10% P) alloy was unattacked by the fuel mixture; however, there were several microscopic cracks present in the fillet. These cracks indicated that this alloy was brittle. It would therefore not be sahsfactory for use in radiator fabrication, The 82% AU—TS% Ni brazing alloy will be retested in ‘_'rhe fuel mlxture because there is considerable dlscrepancy ‘between the results of this seesaw test and the results of the static test.” The 75% Ni-25% Ge brazing alloy on nickel T-joints has been tested in static sodium and in ~ the fuel mixture NaF-ZrF 4-UF , (53.5-40-6.5 mole %) S for ]00 hr at 1500°F Thls alloy showed non- 7E E Hoffmcm, ANP Quar Prog. Rep. Dec. 10, 1954, L 'I'.ORNL 1816, p 83. uniform attack to a depth of 2 mils in sodium and no attack in the fuel mixture. This alloy will be seesaw tested in sodium and in the fuel mixture, Brazing Alloys on Inconel and on Stainless Steel in Lithium C. F. Leitten, Jr. Metallurgy Division Corrosion tests have been completed on three brazing alloys — Nicrobraz, 73.5% Ni—10% Si—16.5% Cr, and 71% Ni-16.5% Cr-10% Si-2.5% Mn — on type 316 stainless steel and Inconel T-joints in static fithium at 1500°F for 100 hr to verify corrosion results previously obtained, The results obtained from weight measurements and metallographic examination of the tested ‘:,::Nicrobraz, specimens are presented in Table 5.12. All the brazing alloys exhibited poor corrosion resistance to lithium, and the attack was more severe on the brazing alloys on type 316 stainless steel. This is probably due to the difference in nickel concentrations in type 316 stainless steel (10 to 14%) and Inconel (75 to 80%). Since nickel is preferentially attacked by lithium, the attack on the Inconel T-joints would be uniform on both the base material and the brazing alloys, which in these tests contained approximately the same nickel concentrations as Inconel. However, the attack would be more concentrated on the brazing alloys on type 316 stainless steel T-joints, be- cause most of the nickel would have to be leached from the brazing alloy in order to reach the solubility limit of nickel in lithium. The results of these tests corroborated the results of the previous tests; that 'is, the nickel-base brazing alloys have very poor corrosion resistance to lithium, especially when used to braze iron-base alloys. Hastelloy B-Inconel in NaF-ZrF,-UF, R. Carlander Pratt & Whitney Aircraft A static test of a Hastelloy B specimen in an Inconel capsule containing a fuel mixture was petrformed to determine whether dissimilar-metal PERIOD ENDING SEPTEMBER 10, 1955 mass transfer occurred in such an isothermal system. The fuel mixture was NaF-ZrF,-UF, (50-46-4 mole %), and the system was held for 100 hr at a temperature of 1600°F. The Hasteiloy B specimen showed a negligible weight loss of 0.0003 g, but no attack could be detected metallographically, Spectrographic analysis re- vealed that no molybdenum had transferred to the Inconel capsule wall., Two 5-mil cuts were machined from the surface of the Hastelloy specimen and analyzed spectre- graphically to determine whether chromium had been picked up from the Inconel tube. Since there was no detectable difference in the chromium content of the two cuts, it appears that no ap- ~ preciable quantity of chromium had transferred. The surfaces of the Hastelloy B specimen and of the [nconel container are shown in Fig, 5.11. Inconel is normally attacked to a depth of 2 mils in an all-lnconel static test system under similar test conditions. The presence of Hastelloy B in the system increased the observed attack on the Inconel to a depth of 8 mils. Boiling Sodium in Inconel E. E. Hoffman Metallurgy Division Tests, to date, at ORNL and at other laboratories indicate that the oxygen content of sodium in TABLE 5.12. BRAZING ALLOYS ON TYPE 316 STAINLESS STEEL AND INCONEL TESTED IN STATIC LITHIUM FOR 100 hr AT 1500°F Brazing-Alloy Composition Cwt o Base Material @ Weight Change* Metallographic Notes Type 316 70 Nl—]4 Cr-6 Fe-—-S B 4 Sl—] C < Incone[ U 73SNIS10SiZ165C 0 Typedls stainless steel 71N'"]0 S$i—16,5 Cr—2.5 Mn - Type 31:6:} Inconel stclniess sfeel .0 'stainless steel “ 17 Joint failed during testing - =0,16 Joint o'fl"aék'eawno'fiuniformly to a posl 0 maximum depth of 9 mils, with - uniform attack to a depth of 4 ‘ 'miis over enhre fnllet , 20,0235 7 L1297 | VJomf falled durlng feshng Braze h”ef complefe!y aflocked‘ ' -0.0949 --1 1.3 7Brcze f|l|ef comp]e.fely afl'acked 0.0312 3.66 Unifomn attack in form of sub- surface voids along fillet *Weight-change data for brazing alloy and base material of joint. 109 T o - RN . Sl .. Wl i e o il S 3 N RS G e, Sl B b, AL . b e et s ot S e S . st o s i " ANP PROJECT PROGRESS REPORT Fig. 5.11. Surfaces of (a) the Enconel Container and (b) the Hastelloy B Specimén Followmg Ekp.bsure to NoF-ZrF4-UF4(50-46-4 mole %) for 100 hr at 1600°F duced 7%. nickel or in iron-base alloy systems has a con- siderable effect on the amount of mass transfer that occurs in the system. Therefore, in order to study mass transfer in a system in which the oxygen content could be held to a very low level, a boiling-sodium loop test was run. The loop is shown in Fig. 5.12. The temperatures around the loop during the 400-hr test are indicated. There are two traps for liquid sodium in the condenser leg of the loop. The first trap is filled with hot, freshly condensed sodium during the test. This .is an ideal location for metal solution to occur. The second trap catches the overflow from the first trap and operates at a considerably lower ‘temperature.” This is an ideal location for metal ‘deposition to occur. Three nickel cooling coils are located on the condenser leg, and air flow - “through these coils is regulated to maintain the ‘desired temperatures. The boiler and the small _return line to the boiler are the only areas where heat is applied. The first test was terminated ~ after 400 hr, when a small leak was detected i the coolest sechon of the bottom return |1ne. X-ray, mccroscoplc, and microscopic examination o Etched with 10% oxalic acid. 500X. Re- UNCLASSIFIED ORNL~LR-DWG 8363 CONDENSER LEG RECEIVER 420°C SODIUM LEVEL DIFFUSION COLD TRAP 10 2 4 bt INCHES Fig. 5.12. lInconel-Boiling-Sodium Loofi. of the traps in the condenser line revealed no mass fransfer (Fig. 5.13). Heavy intergranular cracks were found in the condenser tube wall, and, as yet, no satisfactory explanation has been found. The extent of this intergranular cracking -y i 1o e/ o of fh:s experlmem rs' now under way. "lncone_l fubes loaded wit 1 lithium mixtures in which the lithium content was ‘varied from 2 to 30_wt ‘%.” The ratio of sodium to PERIOD ENDING SEPTEMBER 10, 1955 Fig. 5.13. |hcbhél:-‘rB\-bi'li‘ng--Sodi'um Sys;temVSpecirhens from (a) Hot Trap and (b) Cold Trap of Inconel Condenser Tube Wall. Note heavy intergranular cracks and absence of mass-transfer crystals. 100X, Reduced 11.5%. varied from zero in the hottest section of the in the presence of 5% lithium. It is not yet under- condenser tube to a depth of 3 mils in the coolest stood why the heavier attack occurred in the section, with the heaviest cracking, to a depfh presence of the lower amount of lithium. Additional of 50 mlls, midway between the two traps specimens cut from the hot zone of the tube '(Flg 5, 13) A secbnd tesf' for chec| Na, o + H 0 _ nd ‘H’HS__ work is the first |de_m‘1f|caf|on of Na o as a decompos mon producf ‘ Recent fhermodyncmlc culculc:’nons‘I7 md:cuted that, in addition to the reaction of Eq. 1, dis- sociation is possnble, smuitaneously, ot hlgh @) 2NaOH—=> Na,0, + H, Theamoum‘ of hydrogen observed in these experi- ]7G. P. Smith and C. R. Boston, ANP Quar. Prog, Rep. Sept. 10, 1954, ORNL-1771, p 102, oo Fy Kertesz ments is in excess of that predicted from the calculations. It would appear, qualitatively, that at 800°C o significant proportion of the decomposition product is in the peroxide form. CHEMICAL STUDIES OF CORROSION H. J. Buttram Materials Chemlsfry DIVISIOI‘I _.Inconel in NaF-LiF- ZrF -UF H. J. Buttram R. E. Meudows - Materials Chemistry Division A series of studies in which the four-componem‘ “fuel ‘NaF-LiF-ZrF 4-UF (22-37.5-35.5-5 mole %) was exposed for ]00 11r in sealed capsules of Inconel in the standard rocking furnace has indicated that this mixture may be less corrosive than others under consideration. The data ob- tained for this mixture and for three other previ- 119 RO AT ot Ry ORERIE ANP PROJECT PROGRESS REPORT Fig. 5.20. Inconel Strips (25 mils thick) Tested at 800°C in Sodium Hydroxide. Strips 1 to 4 were exposed 7, 28, 54, and 100 hr, respectively. Number 0, a control strip, was unexposed. ously tested materials run as standards are shown in Table 5.16. Stability of UF; in NaF-KF-LiF in inconel H. J. Buttram R. E. Meadows Materials Chemistry Division A series of mixtures of the NaF-KF-LiF eutectic containing added UF; and UF, has been exposed in sealed capsules of InconeT for times ranging from 3 to 240 hr in the rocking furnace. The capsules were heated and maintained at a hot-end temperature of 800°C and a cold-end temperature of 650°C. The rocker was operated at 4 cpm. The total uranium contents of the mixtures studied were 10 to 20 wt %. After exposure the capsules were opened and unloaded in a helium-filled dry box, and the cooled melts were ground and - analyzed chemically for UF, and UF,. As the data in Table 5.17 indicate, UF, is quite unstable under these conditions, regardless of the orjgino] UF,/UF, ratio. It appears that con- siderable disproportionation of UF, must be "expected in this system under all circumstances. 120 Effect of Chromium on the Mass Transfer of Nickel in NaOH H. J. Buttram R. E. Meadows F. A. Knox Materials Chemistry Division The effect of chromium on the mass transfer of nickel by NaOH was tested in a nickel rocking furnace. The exposures, at 4 cpm, were for 100 hr, with the hot ends of the capsules at 775°C and with a 100°C temperature drop along the capsules, When 1 wit % Cr® was added to the purified NaOH, the mass transfer of nickel was reduced by about a factor of 2. However, in no case was the mass transfer eliminated, Analyses of the caustic revealed the presence of about 4000 ppm Ni in the tests without chromium added to the NaOH, while about 2500 ppm Ni and 3200 ppm Cr were found in the caustic to which 1T wt % Cr® was added, This decrease in mass transfer presumably can be explained by the reaction of Cr® with NaOH to yield hydrogen gas, which tends to suppress the reaction of NaOH with Ni®. Since hydrogen diffuses readily through nickel metal at the test tempera- ture, these experiments were repeated with the nickel capsules enclosed in evacuated, sealed quartz jackets. In addition, two capsules were sealed in quartz envelopes containing hydrogen at 540 mm Hg pressure. After 100 hr in the rocking furnace, no mass transfer was found in any of the capsules, except one for which the quartz envelope had cracked. This lack of mass transfer was evident, however, even in the control capsules containing no chromium, Furthermore, analyses of the caustic after the tests showed quite low (less than 100 ppm) concentrations of nickel and chromium. Pressures inside the quartz envelopes, obtained by breaking the quartz inside an evacuated standard volume, were about 350 mm Hg (590 for the one initially set at 540 mm Hg). The gas was not analyzed, but it is presumed that it was hydrogen. From these studies it is not apparent that chromium is particularly beneficial. It does appear, however, that some mechanism to prevent loss of hydrogen from the system — perhaps cladding the nickel with some metal impervious to hydrogen — might be quite beneficial, o Y PERIOD ENDING SEPTEMBER 10, 1955 TABLE 5,16, CORROSION OF INCONEL CAPSULES EXPOSED IN ROCKING-FURNACE TESTS FOR 100 hr TO SEVERAL FUEL MIXTURES Chromium Found in Fuel Mixture Depth of Attack on Fuel Mixture Composifion' After Test Inconel Capsule (ppm) (mil} NaF-LiF-KF 410 | | 1 (11.5+46.5-42 mole %) NaF-Zr F4 ‘ 760 1 (53-47 mole %) ' ' NcF-ZrF4-UF4 1370 ' 1 {53.5-40-6.5 mole %) NaF-LiF-ZrF,-UF, 220 0.5 (22-37.5-35.5+5 mole %) TABLE 5.17. DISPROPORTIONATION OF UF, IN NaF-KF-LiF EUTECTIC IN INCONEL CAPSULES | TESTED IN THE ROCKING-FURNACE APPARATUS Hot-zone temperature: 800°C Cold-zone temperature: 650°C Uranium Compounds Found (wt %) Uranium Compounds Added (wt %) After 3 hr After 27 hr After 243 hr UF, UF, UF, UF, UF, UF, UFy UF, 12.4 0 2.0 5.98 3.6 7.6 1.8 9.3 6.4 6.4 2.3 9.2 2.4 9.2 1.8 10.8 1.3 11.8 0.1 12.7 0.1 o127 0.3 12.5 o | 2.9 0.2 13.1 180 57 214 23.0 3.4 20.6 270 0 © 255 263 o1 2560 121 ANP PROJECT PROGRESS REPORT 6. METALLURGY AND CERAMICS W. D. Manly J. M. Warde Metallurgy DlVlSlon Stress-rupture tests are being mode of /-m. Inconel tubing in argon and in fused salts in order to evalucte the effects of the biaxial stresses ‘present in pressurized tubing. The results of tube- ‘burst tests are compared with those of tensile 'creep-rUpfure tests of 0,060-in.-thick sheet in argon ‘and in fused salts at 1500°F. Data from creep-rupture tests of 0,020- and 0.060-in.-thick ‘Inconel sheet are presented which show that rup- ture life for a given stress is shorter for the fhlhner'sh'ee'rw An evaluation of a welded Inconel bellows for use in fused salts at high temperatures and the resulfs of a study of the interaction be- tween Inconel and beryllium under pressure in an :merf environment are presented. Additional oxidation and fabrication studies of mckel-molybdenum alloys are discussed, and de- ~sign curves for solution-annealed Hastelloy B tested in fused salts at 1500 and 1650°F are given. The influence of aging on the creep-rupture properties of Hastelloy B is being studied, and data are presented for creep-rupture tests of aged and solution-annealed material in argon at 1500 and 1800°F and for short-time fensile tests of ma- terial aged at high temperatures. The results of static and cyclic oxidation tests at 1700°F on several brazing alloys are presented. Several components containing cermet-to-Inconel joints were successfully brazed, and techniques of brazing boron carbide are being investigated. The lnconel core-shell assembly for the high- fempero'rure “critical experiments was fabricated “after eXper:mentcl techniques for minimizing dis- “tortion were developed. Methods of producing - ';j'_fquanfmes of Coclsf Metals No. 52 presintered - brazing clloy rings were developed in preparation ~ for the impending construction of another large 'V{_NGK-fo-alr racllafor. A second sodiumsto-air radia- " tor was completed for the Corell Aeronautical : 'Laboratory, ‘and two fuel-to«NaK heat exchanger o ff’rube bundles are being fabricated. "~ The bas;c‘ concep’rs of eddy-current testing as applied to low-conductivity alloy tubing are dis- ¢ussed, The merits of the impedance analysis " method are presented, along with problems of flaw detection with both encircling and probestype '7":c0|ls._ An ultrasomc method for the inspection of e small-d(cmefer tubing is descnbed thaf is suf- ficiently sensitive to detect the types of flows encountered to date. The investigation of corrosion-erosion in the graphite-hydrogen system at high temperatures was continued, Two control rod assemblies of rare- earth oxides were fabricated, as well as calcium fluoride and alumina spacers. The optimum press- ing conditions for pelletizing fluoride fuels are being studied, and an investigation of the feasi- bility of synthesizing Mo,B. and B,C is under 275 way. Dysprosium oxide disks and ~europium oxide wafers were fabricated. The special materials studies reported include the results of studies of diffusion barriers for use between Inconel and columbium and a discussion of further attempts to prepare two- and three-ply tubing. The results of oxidation tests of several commercial aluminum bronzes being considered for oxidation protection of copper radiator fins are presented. Attempts to prepare creep-resistant lead-calcium alloys for use as shielding material are described, as well as experimental work under ~way for preparing B,C.Cy neutron shielding ma- terial for the ART, MECHANICAL PROPERTY TESTS OF INCONEL D. A. Douglas J. R. Weir J. H. DeVan J. W. Woods Metallurgy Division C R. Kennedy, Pratt & Whitney Aircraft Stress-Rupture Tests J. H. DeVan Metallurgy Division Stress-rupture testing of %-in. inconel tubing in argon and in fused salts at 1300, 1500, and 1650°F is now in progress., Although data for Inconel tubing at 1300 and 1650°F are as yet incomplete, the results of tests of Inconel tubing with wall thicknesses of 0.010, 0.020, 0.040, and 0.060 in. at 1500°F in argon and in fused salts are suffici- ent to show important trends. In studying the biaxial stress system set up in the tubes, the question arises as to whether failure is related to the effect of combined stresses or » R A whether, 1he maximum stress component (in this case, hoop stress) singularly controls the time to failure, A comparison of the results of tensile creep-rupture tests and tubesburst tests is pre- sented in Fig, 6.1 for tests in argon and in Fig. 6.2 for tests in NaF-ZrF 4~UF, (50-46-4 mole %). It may be seen that there is good agreement be- tween rupture times for 0.060-in.-wall tubmg and 0.060-in.-thick sheet in both environments. Thus, the presence of an axial stress in the tubing does not appear to affect the time to failure, It may be noted, however, that the specimens “with thinner walls, 0,010 to 0.020 in., ruptured in ‘much shorter times than those observed for 0.060- in.~thick sheet specimens at comparable stresses, While this was originally thought to be due to the effect of the combined stress system acting in the tubing, it now appears from the results of tests on 0.020-in.-thick sheet that the poor rupture propet- ties are associated with the smaller section thick- ness. PERIOD ENDING SEPTEMBER 10, 1955 The results of creep-rupture tests of 0.020-in,- thick Inconel sheet in argon and in hydrogen at 1500 and 1650°F are compared with those of tests of 0.060-in.-thick sheet in Table 6.1. As may be seen, a substantial reduction in rupture life ac- companies the reduction in section size, Bellows Test J. H. DeVan Metallurgy Division An evaluation of a welded-diaphragm bellows for use as a seal in a shut-off valve for controlling the circulation of fused salts was conducted by utilizing a modified creep-rupture machine to simu- late operating conditions. [n this equipment the bellows was deformed while the outside and inside surfaces were in contact with the fused salt mix- fure NGF-ZrF4-UF4 (53.5-40-6.5 mole %). Tests were made at 1300 and 1500°F, each for 100 hr, A leak check following each test failed to indicate UNCLASSIFIED ORNL-LR-DWG 8936 10,000 — LT - FINE-GRAIN, 0.060-in.- THICK SHEET ™ . \:\\ . \ = 5000 s ,k\ o } \ N w \ A N 2 O A & \ | ’_ ‘e SRR = SETN . \ o= - 2 = - = Al N e © 34-in.~ID, 0.060 -in.-WALL TUBING NN \ 9 ® 3-in-10, 0040 in.- WALL TUBING \\ \ 2000 ——— 1,1in.-1D, 0.020- in.- ~WALL TUBING " SN 4 Ypin-ID, 0.010-in“WALL TUBING N 7800 1000 2000 5000 Fig. 6.1.- 10,000 Comparison of Tube-Burst and Stress-Rupture Tests of Inconel in Argon at 1500°F. 123 ANP PROJECT PROGRESS REPORT ORNL-LR-DWG 8937 10,000 L FINE- GRAIN, 0.060-in.- THICK SHEET ™ <\ \\ 5000 A \ = \ 2 \ \ 9} A \\ \\= };\ & \ NN 5 N ON| oy N RN = , \ g O 3,-in.-iD, 0.060-in.-WALL TUBING N \ " ® 3,-in.-ID, 0.040-in.-WALL TUBING \\ \\ N 2 & Yy-in.-ID, 0.020-in.- WALL TUBING *\ O S oo A Yo-in.~1D, 0.010-in-WALL TUBING \ | N \\ | ]\ \\ \\ 1000 AL , ' { 2 5 10 20 50 100 200 500 1000 2000 5000 10,000 RUPTURE TIME (hr) Fig. 6.2, Comparison of Tube-Burst and Stress-Rupture Tests of Inconel in NaF-ZrF4-UF4 (50-46-4 mole %) at 1500°F. TABLE 6.1. COMPARISON OF RESULTS OF STRESS-RUPTURE TESTS ON 0.060- AND ' 0.020-in.-THICK INCONEL SHEET Time to Rupture (hr) Total Elongation (%) Temperature Stress (°F) (psi) Atmosphere 0.020-in.- 0.060-in.- 0.020-in 0.060-in.- Thick Sheet Thick Sheet Thick Sheet Thick Sheet 1500 3500 Argon 270 1467 8 13 Hydrogen 350 618 n 8 1650 2000 Argon 740 1125 14 30 Hydrogen 200 385 12 N any flaws in the bellows. Metallographic examina- tion showed only normal corrosive aftack in the weld areas, and no cracks could be detected as a direct result of the flexing of the bellows. _-_Interq_;fipn Bgtween Inconel and Beryllium A programfordefermmmg the extent of inter- action between beryllium and Inconel at elevated temperatures in an inert environment was'reCentIy completed to establish design limits for the high- temperature critical experiment. The - modified creep-rupture equipment was used for the tests so that a conirolled atmosphere of argon could be maintained and a specified load could be trans- " wh mitted to the specimens of beryllium and Inconel at 1350°F, The results of the three tests are summarized in Table 6.2, | The diffusion area in the Inconel specimen from the 100-hr test is shown in Fig. 6.3. The extreme hardness, as shown by Knoop indentations, and the sharp interface of the diffusion area indicate TABLE 6.2. RESULTS OF TESTS OF THE INTERAC- TION BETWEEN INCONEL AND BERYLLIUM UNDER 'DIFFERENT PRESSURES FOR CONTACT TIMES OF 40 AND 100 hr ' Time in Contact Depth of Alloyed Contact Pressure Region in (hr) (psi) tnconel (in.) 100 500 | 0.015 40 - 100 | 0.005 40 50 0.003 PERIOD ENDING SEPTEMBER 10, 1955 that an intermetallic layer was formed by the inter- action of the beryllium and the Inconel. This layer is, undoubtedly, detrimental to the load-carrying ability of the Inconel, although it represents an extremely small percentage of the cross section of the specimen tested. DEVELOPMENT OF NICKEL-MOL YBDENUM ALLOYS J. H. Coobs J. P. Page H. Inouye T. K. Roche . Metallurgy Division M. R. D'Amore, Pratt & Whitney Aircraft N | Oxidution‘Studies Experimental data obtained on the oxidation in static air at 1500°F of several nickel-molybdenum alloys are presented in Table 6.3. The alloy with the nominal composition 10% Mo-10% Fe-6% Cr— 74% Ni was tested previously in a fluoride mixture - Fig. 6.3.- Diffusfon Area in k|ncone| After Contact with Beryllium for 100 hr at 500 psi.v 500X. Reduced 5.5%. 125 ANP PROJECT PROGRESS REPORT TABLE 6.3. OXIDATION RATES OF NICKEL-BASE ALLOYS IN'STATIC AIR AT 1500°F FOR 167 hr Ce e Wéight.gain ) Al.l‘lox o (g/cmz) Remarks 10% Mo—-10% Fe—-6% 0.0005 Ac”;erent oxide Cr --?4% N.i formed ”H"as;teu;'y B, 0.0010 vacuum melfed Oxide spalled upon cooling | 2.5% Be-97. 5% N| 0.0004 Adherent oxide i , o formedr _ 2.5% Be--S% - 0,0014 Adherent oxide Cb-‘9_2.5% Ni 7 7 forr_ned and was found to be promising. Its oxidation rate was between that observed for a 7% Cr—-20% Mo~- 73% Ni alloy and that for a 10% Cr-20% Mo—70% Ni alloy. Further, it is considered to be heat resistant, and it forms a nonspalling oxide upon oxidation. The samples from a vacuum melt of Hastelloy B supplied by the Haynes Stellite Com- pany showed no significant differences from com. mercial grades of Hastelloy B, The 2.5% Be- 97.5% Ni alloy also forms a nonspalling oxide and is considered to be heat resistant, The addition of 5% Cb, however, increased the oxidation rate to that observed for Hastelloy B. Fabrication Studies [t was reported previously! that a deleterious effect in nickel-molybdenum alloys containing titanium, aluminum, vanadium, zirconium, colum- bium, or chromium was noted after long heat treat- ments in hydrogen. Additional similar tests were ]J. H. Coobs, H. Inouye, and M. R. D'Amore, ANP Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 120. TABLE 6.4, ROOM—TEMPERATURE TENSILE TESTS OF 0 065-m SHEET SPECIMENS OF made to ensure that the effect was au'e'fo hydrogen . and not to the aging heat treatment, The check __:_‘tesfs were made on a 5% Cb-20% Mo-75% Nl‘_ . “alloy. The results of the tests, presented in Table 6.4, verified that low strength and duc- tility resulted from long exposure in hydrogen at elevated temperatures. The tests also indicated that the effect of hydrogen could be removed by vacuum annealmg. The possibility that a hydride forms during aging has been suggested, but, if such is the “case, embrittlement in alloys containing chromium and aluminum cannot be explcined The embrittie- ““ment effect was not detected in tests of Hastelloy B and of the binary nickel-molybdenum alloys, and it was not found in all the elevated-temperature - tensile tests of the ternary alloys that have been studied. Twelve extrusions of Hastelloy B were attempted by the Babcock & Wilcox Co. to determine the commercial feasibility of making tube blanks for seamless tubing. This effort was supported by the Haynes Stellite Company, Each of the twelve extrusion attempts were unsuccessful because of severe cracking of the tube blanks or failure to extrude (‘‘stickers’’). The extrusion temperatures used were between 2000 and 2250°F, Based upon experience at ORNL, it is concluded that improper temperatures, socking time, and press capacity were the main causes of failure, Since this effort was made because successful extrusions had been made at ORNL, additional ex- periments were performed here to verify the recom- mended extrusion conditions, to verify, with a different heat, the superior redrawing properties of the exfruded tube blonks, cmd fo de‘rennine meth_cr)d&s N 5% Cb—20% Mo-75% Ni ALLOY 'Specimens annealed 1 hr at 21QOOF and aged at 1650°F Yield Point, Reducflon o e : by 2hr in vacuum Condifiofi of Tést Specimen 0.2% Offset Tensile Strength Elongation in Area - Aged 285 b in vacuum | 78,500 153,700 35 A Aged 285 hr in hydrogen | 77,600 113,600 h 13 _ Aged 285 hr in hydrogen followed 78,300 ]51,000 30 126 S o e b S for reducing. the pressure required for the extru- sion. Two uncanned billets of Hastelloy B were successfully extruded into tube blanks at an ex- ~trusion ratio of 5.5/1, The recommended condi- _ tions were verified: namely, temperature, 2000°F; ‘heating time, 45 min per inch of billet thickness; and extrusion pressure, 80 to 90 tsi. These tube blanks are to be redrawn to small-diameter tubing. A Hastelloy B blllef conned in / ¢-inethick Inconel was extruded at 2100°F at an ex'rrus:on ~ ratio of 5.5/1, The pressure required for this ex- " trusion was 55 tsi, as compared with 80 tsi for the uncanned billets, A second canned extrusion was made at a ratio of 9/1 at 2100°F with fair success, At these temperatures, the first billet, if uncanned, would have cracked severely. The high extrusion ratio used for the second extrusion would have caused the blHef, if uncanned to be a sticker, The use of Inconel as cannmg material for Hastelloy B is justified, since it serves a three- fold purpose.. Besides acting as a lubricant, the Inconel provides a thermally bonded oxidation- resistant tayer for the alloy. Also, in a high- temperafure air stream, the Inconel would inhibit formation of the corrosive MoO vapor, and thus there would be no possibility of catastrophic oxi- dcmon occurring in the structural material, More- over, the clad Hastelloy B could probably be re- duced more successfully than the unclad material, because Inconel is not sub|ect to ‘‘heat cracking,’’ that is, surface cracking durmg cnneahng of cold work that is aftributable to poor themal conduc-. tivity and a high rate of work hcrrdemng. PERIOD ENDING SEPTEMBER 10, 1955 STRESS-RUPTURE TESTS OF HASTELLOY B D. A, Douglas Metallurgy Division C. R. Kennedy Pratt & Whitney Aircraft A series of creep-rupture tests has been com. pleted on solution-annealed Hastelloy B at 1500 and 1650°F in the fluoride mixture NaF-ZrF -UF (50-46-4 mole %). The results are summanzed m design curves presented in Figs. 6.4 and 6.5. A similar series of tests is nearly completed for solution-annealed Hastelloy B at 1300 and 1800°F in argon and in the fluoride mixture. The influence of aging heat treatments on the creep-rupture properties of Hastelloy B is being studied at several temperatures ranging from 1300 to 1800°F. In general, aged specimens have shown marked reductions in creep rate and tensile elongations compared with specimens in the solu- tion-annealed condition. Results obtained from creep-rupture tests on solution-annealed and aged specimens at 1500 and 1800°F in argon are pre- sented in Table 6.5, The creep-rupture properties at 1800°F are not substantially affected by aging, since at this tem- perature a single-phase alloy exists. However, at 1500°F, a second phase that appears upon aging produces a marked change in the creep-rupture properties of the alloy. It may be noted that for stresses which produce a rupture life in excess of 100 hr for the solution-annealed material at 1500°F the difference in rupture life of the solution~ This is annealed and aged specimens is small. . understandable, since, during testing at this tem- ~Two additional tube b!anks of_q\]57 M'o.-ss% N peroture, the solunon-annealed specimens actually .. age.” During testing at higher stresses, the solu- V__:_:hon-c‘:nnealed materlul does not age appreciably before rupture, and thus the rupture times for the aged specimens are opprecmbly longer than those for the squhon-anneoled Spec:mens. PHYSlCAL PROPERTIES AND MICROSTRUCTURE STUDIES OF HASTELLOY B afier aglng, modifications o _VHClstelloy B. Furf loy W, d fhe""effect of shqht composmon e mechar 'cal prOpen‘les of ,""cvresearch program parailel-”‘f"w_ ‘ing that of Hastelloy B is com‘emplafed for Hasfel-\- P chfrlarca R. E. Clausing ' Metallurgy Division Short-tume 'rens:le tests conducted after long-time " aging of Hasfe]loy B at elevufed temperatures in- " dicate that residual stresses not removed affer a 127 ANP PROJECT PROGRESS REPORT ’ ORNL—I!R—DWG 8938 20000 = ELONGATION 1% RUPTURE 15,000 12,000 STRESS (psi) 10,000 6000 1 2 5 10 20 50 100 200 500 1000 2060 5000 10,000 TIME (hr) Fig. 6.4. Design Data for Solution-Annealed (2100°F), 0.060-in.-Thick Hastelloy B Sheet Tested at 1500°F in NoF-ZrF -UF , (50-46-4 mole %). ‘ TABLE 6.5. RESULTS OF CREEP-RUPTURE TESTS ON AGED AND SOLUTION-ANNEALED HASTELLOY B AT 1500 AND 1800°F IN ARGON Test Final Temperature Condition Stress Rupture Time Elongation (°F) (psi) (h) (%) 1500 Solution annealed 12,000 | 1180 20 Aged 40 hr at 1500°F 12,000 1450 16 ~ Aged 70 hr at 1500°F 12,000 1070 8.7 Solution annealed 13,500 170 16 Aged 100 hr at 1300°F 13,500 670 57 Solution annealed 15,000 160 49 Aged 100 br at 1300°F 15,000 330 n 1800 Solution annealed 5,000 112 12 Aged 100 hr at 1300°F 5,000 - 90 10 Solution annealed | 3,500 410 7.3 Aged 100 hr at 1300 3,500 300 59 S8 PERIOD ENDING SEPTEMBER 10, 1955 ORNL—-LR-DWG 8939 14,000 ' 12,000 4 ELONGATION {% (2% 5 % 10 % RUPTURE 10,000 \ = \ \\\ \\ . N N ™ \ \ \\ ™ N z ™~ NN s ™\ L NN & \ N N W \ N ‘ NNEEANY = ™~ N 0 k \\ \\ \ \ ™ . ™ u \ \ SN ~ \ ny \ § 5000 \\ NG N 4000 : f 2 - 10 20 50 100 200 500 1000 2000 5000 10,000 - ' . TIME (hr) | Fig. 6.5. De5|gn Data tor Solutlon-Annealed (2100° F), 0 060-|n.-Th|ck Haste!loy B Sheet Tested at 1650°F in NaF Z:F -UF (50-46-4 mole %) celd-WOrl(ing opereti"efi‘er]e ‘qu'ite.detr'imentct to the 1500°F ate-:c':eriksid\erd'l")ly grecter.' than the ductili- Tensile specimens, which t:es of those aged at 1400°F. This may be due to ‘a reduced amount of beta phose, which may be aB_Ie dt 1500°Fm The gamma phase appears to be A ~ ductility of this alloy. - haod been cast from sheet that hadw been cold- o AR “from 1100 to. 1500°F in i R e nd teeted at_ both roomvand,“elevute- SR e A G reRR in_ Table 6.6 show__.consflémb,‘xfijower o ERATIAR G d'uctthty for the cold-wo = B i ”"“'noted that the ductliltles 3\‘ the specxn';enaswoged at the onalyses of the ef'Fectsf 'ot heat treatment . 129 will cf.d consnderably In A ‘ANP PROJECT PROGRESS REPORT ' TABLE 6.6. RESULTS OF SHORT-TIME TENSILE TESTS OF HASTELLOY B ) AGED AT HIGH TEMPERATURES Teh.sile :Yie!\d:i BRAZING ALLOY DEVELOPMENT AND TESTING P. Patriarca R. E. Clausing Metallurgy Division , Developments Tests The OXIdelOI’I re5|stance of high-temperature brazing alloys under static conditions at 1500 and 1700°F and in cyclic service at 1500°F has been reported 2,3 The results of cyclic tests at 1700°F are repon‘ed in Table 6.7. It can be seen that the cycled from room temperofure to 1700°F is greater than thot of [omfs ‘tested at a constant tempera- ~ ture. The Coast Mefals No. 52 alloy, which is " ysed exfens:vely in brazmg h:gh-conducflwty-fin V‘radrctors, was atfacked severely in these tests, f_jjwhtle fhe chroml‘um-bearmg Coosf Metals No. 53 2P Po'rnarca et al. ANP Quar Prog. Rep March 10, 955, ORNL-1864, p 121. 3P Patriarca et al., ANP Quar. Prog. Rep. June 10, 955, ORNL- 1896, P 130. extent of ox;dahon of brazed joints thermally' alloy was not. The No. 53 alloy will therefore be seriously considered for this fabrication applica- tion, even though a higher quality hydrogen atmos- phere may be required to obtain flow with this chromium-containing alloy. Melting point studies are being made on the high-temperature brazing a“oys by usmg “sintered, conical samples. The cones are smtered from flnew powder in a Lavite mold and heated at various tem-T T} peratures on a thin, nickel sheet in a dry-hydrogen'_'* T atmosphere. The results of studies on a ’rypuca] . brazing alloy, Cocsf Metals No. 52 ore shown in o E F;g. 6 b. Brazing of Boron Carbide : Agmg - Aging Tesf ""Tem‘;‘)erd;c;e ~ Time Temperature Ductility Strength Point S CFY (hr) R (%) (psi) (psi) Cold Reduced 20% Before Aglng _ 500 Room o 3.0 181,300 ,f.] 154,600 500 1100 2.5 130,500 115,500 500 1100 3.5 122,900 104,400 200 Room 0.8 173,500 150,000 200 Room 0.5 191,600 148,000 | 500 Room 3.8 164,000 88,200 500 1400 6.3 84500 T 500 Room 20.0 163,000 100,000 500 ‘ 1500 30.0 64,600 Fu“y Annealed Before Aging _ 500 Room 14.0 126,000 zgoco T g 500 1100 14.0 91,100 58,600 ; 500 Room 6.0 92,600 6,000 : 500 1300 12.5 140,600 90,000 500 Room 20.0 128,000 73,500 500 1400 10.0 76,500 ' ' 500 Room 12.5 109,800 54,900 500 1500 37.5 63,100 ) The incorporation of a boron carbide radmhon: e shield into a fused-salt pump assembly req that the boron carbide compact be brazed to cn it Inconel envelope to provide sufficient thermal con- ductivity to remove the heat induced by radiation. The service temperature may be as high as 1700°F, with helium as a protective atmosphere. Although ' 'TABLE 6.7, OXIDATION RESISTANCE OF DRY- HYDROGEN BRAZED INCONEL T-JOINTS TESTED FOR 500 hr AT 1700°F - _ -’; _Oxid'c'rion with Oxidation 220 Air Cools Brazing Alioy* ip Static to Room Airr Temperature** Wall Colmonoy Nicrobraz .Slight Slight Coast Metals No. 53 . Slight Slight Wall Colmonoy lowsmelting Slight Moderate Nicrobraz Coast Metals No. 50 Slight Moderate Pd-Ni (60-40 wt %) Slight Moderate Pd«Al (92-8 wt %) ~ Slight Moderate Coast Metals No. 51 Slight Severe Coast Metals No. 52 Slight Severe Coast Metals NP Mdderafe Moderate G-E No. 81 MQJerote Moderate . : Ni-Ge (75-25 wt %} " Moderate Moderate Ni-Ge-Cr (65-25-10 wt %) Moderate Moderate N i-Mo-Ge (50-25-25 wt %) Moderate Moderate : AuNi (82-18 wt %) Moderate Severe Au-Co (90-10 wt %) ' Severe Severe , Pd-Ge (90-10 wt %) o :“C_ompr|efe Complete ' Ni-Sn (68-32 wt %) 'Com.plefe " Complete Ag-Pd-Mn (64-33-3 wt %) Complete Complete Ni-Mn (40-60 wt %) " Complete Complete Ni=Mn-Cr (35-55-10 wt %) Complete Complete Au-Cu (80-20 wt %) ~ Complete Complete Ni-Mn (40-60 wt %) Complete Complete Copper Complete Complete *Alloys listed in order of decreasing oxidation re- * mstonce. . **Very shght Iess than 1 mal of penefrahon sl:ghf _ 1to 2 mils of penetration; moderate, 2 to 5 mils of pene- “tration; severe, greater than 5 mils of penetrahon, coms- PERIOD ENDING SEPTEMBER 10, 1955 a large number of high-temperature brazing alioys have been tested, none investigated to date have proved entirely satisfactory, Most of the brazing alloys which wet the boron carbide also react with it to form brittle bonds that crack upon cooling. The most promising alloys tested thus far are those that either contain zirconium as a component or require an application of zirconium hydride powder to the boron carbide surface prior to place- ment of the brazing alloy on the same surface, Experimental alloys are now being prepared to permit a more thorough investigation, Brazing of Cermet Valve Seats to Inconel Components Three assemblies incorporating Kentanium cermet valve parts have been successfully brazed by using the technique described previously.* An exploded view of an assembly for determining the self- welding characteristics of these cermet valve parts is shown in Fig. 6.7. This assembly consists of an Inconel structural piece, two copper-foil disks that supply brazing alloy for the lnconel-to-nickel joint, @ I/4--1in.-thi<:l-< nickel block to dissipate ther- mal stresses resulting from the different coeffici~ ents of thermal expansion of Inconel and Kentani- um, a copper-foil disk to supply supplementary brazing alloy for the nickel-to-Kentanium joint, and the Kentanium seat plated with a 0.0001-in, layer of nickel-phosphorus followed by a 0.003-in, layer of copper on the surface to be brazed, ‘Figure 6.8 shows an actual valve subassembly, which is similar to the assembly for self-welding studies except for the omission of several copper- foil disks, Copper powder, which was substituted for the disks, was placed in especially provided . pie*er f||[ef completely destroyed. *1bid., p 145. 1000°C 1020°C Fig. 6.6. Melting-Point Determinations of Coast Metals No. 52 Brazing Alloy Made by Using Sintered Cones Heated on Thin, Nickel Sheet in a Dry-Hydrogen Atmosphere. " 131 ANP PROJECT PROGRESS REPORT 'UNCLASSIFED © receésses. The complete valve is shown after Y-16173 . L x brazing, but prior to finish machining, in Fig. 6.9, o }... ¢. i w FABRICATION OF TEST COMPONENTS f J Components for High-Temperature y \/ "** . T Critical Experiment g x - “ P. Patriarca tg & S g Metallurgy Division z = ; L ' /U\ + S The fabrication of the inconel core shell for the X S i high-temperature critical experiment required ex- ’ tremely close control of the distortion associated : A x with production of the girth weld. Preliminary & % a experiments were therefore conducted to determine, U T YREUKE D YA SEAT DiSK {£) BRAZED ASSEMBLIES Fig. 6.7. Assemblies for Self-Welding Studies of Fig. 6;9. Brazed Valve Aésembiy Pribr‘ to a TiC-Ni Valve Seat and Disk. Machining. Fig. 6.8. V.olvéISeat and DlSk Subussembhes. " 132 o ”w ~dnd the oufe cc;re “shell T » “inner shell, The complefed Ieakhght' umt |s shown ‘in Fig..6 12, N qucnhtahve!y, the extent of distortion to be exs pected. The first test consisted in the deposition of a butt weld between two cylindrical segments 4 in, in depth, Each segment was machined from a nominal, 12-in.~ID, sched-40 pipe, in which the inside diameter was bored to 12,250 in. to improve the roundness and the ou'rsrde diameter was tumed down to 12,500 in. to provide a 0,125.in. wall for 3 in. of the 4-in. depth. A stainless steel face plate was tack-welded at 60-deg intervals to the l-in, shoulder of each segment to provide a degree of restraint intended to approximate that provided by the tapered reduction in diameter of the island sheath. Micrometer caliper measurements at 48 scribed positions indicated that a maximum change of 0.030 in. occurred in the nominal 12,5-in. out- side diameter, As was expected, the frequency of large changes increased wn‘h increasing proximity to the weld. o A second test was conducted to determine the extent of distortion to be expected when butt- welding the spun core segments with the aid of mechanical support, Two 6-in.-deep Inconel cylin- ders, 12,5 in. OD, ]/s-in. wall, were butt-welded with an aluminum backing ring containing Lavite inserts for support. Micrometer and dial-gage measurements made at 96 positions on the weld- ment, before and after welding, indicated a maxi- mum shrinkage of 0,020 in. on the 12.5-in, outside diameter, that is, an improvement of 0,010 in. over the shrinkage obtained without mechanical support. ~The information gained in these experiments was then utilized in the fabrication of the actual core shells, The upper and lower halves of the “inner shell were stress-reheved in dry hydrogen | for 2 hr at 1500°F with heating and coolmg times of 3 hr. They were then machined to the desired length and beveled to fac:htate weldmg. Berylhum blocks were fhen ‘assembled in the island inner = ‘ :_core, as shown in Flg. 6. ]0 The outside of the :slund core shell_ is_shown in Fig. 6. ]] ofi*er com- Two control rods were also fabricated for the high-temperature critical experiment. Inserts of PERIOD ENDING SEP TEMBER 10, 1955 Fig. 6.10. Lower Half of Inconel Island Core Shell Showing Stacked-Beryllium«Block Inner As. sembly Before Positioning of Upper Half of the Core Shell. rare-earth oxides were assembled in the control rod housing and sealed by welding. NaK-to-Air Radiator P. Patriarca G. M. Slaughter Metcllurgy Division R L. Heestand | Prcfi & Whlfney Aircraft The fabr:ca’rlon of a third, 500-kw NcK-to-mr rad:q’ror with type 310 stainless-steel-clad copper, high-conductivity fins, is under way, Although the design of this unit is essentially the same as that of the radiators fabricated previously,® a few modifications in the fabrication techniques will be utilized. These modifications include the SIbid., p 134. 133 ANP PROJECT PROGRESS REPORT Fig. 6.11. Completed Island Core Shell After Deposition of the Girth Weld. construction of a 36-hole punching die to assure a uniform fin-punching geometry, the construction of new tube-bending dies for close control of the tube-bending variables, the development of techniques to permit the assembly of headers in such a manner that all the tubes will enter normal to the curvature of the header at the point of entrance, and the utilization of the presintered- ring method of brazing-alloy preplacement. Techniques for the preparation of presintered rings of Coast Metals No. 52 brazing alloy were developed by personnel of Pratt & Whitney Aircraft.® The alloy is sintered in suitable graphite molds in a dry-hydrogen atmosphere to form rings that possess adequate strength and rigidity. Molds of the type shown in Fig. 6.13 . were used to prepare approximately 45,000 rings, SPratt & Whitney Aircraft, Nficlear Propulsiofi Proe ram Engineering Prog. Rep. No. 15, PWAC 551, p 71 o (1955). 4 Flg. 6;12.. ’Completed. Core As‘semblly Shéfiing Outer Core Shell and Upper and L.ower Hubs. 3/16 in. in inside diameter, Exper-imenfs conducted on 12-in. lengths of vertically brazed tube-to-fin joints have indicated that good flowability and edge-protection of the copper on the punched fin lips can be obtained with the use of these brazing- alloy rings. Intermediate Heat Exchanger No, 3 P. Patriarca G. M. Slaughter Metallurgy Division R. L. Heestand Pratt & Whitney Aircraft One 500-kw, fuel-to-NaK heat exchanger tube bundle has been fabricated for the third series of intermediate heat exchanger experiments, and the second tube bundle is partially completed. Although these bundles are similar to those incorporated? 7P. Patriarca et al,, ANP Quar. Prog, Rep. June 10, 1955, ORN|.-1896, p 131. Ll T T 7 CM 52 ALLOY in intermediate heat exchanger No. 2, several design changes have been made to promote better operating characteristics and to aid in fabrication. Larger diameter tubing, 0.250 in., is being used, and the right-angle corners of the header components of the previous heat exchanger have been eliminated ‘The new desngn is shown in Frgs 6.14 and 6.15. is shown at ishell design to faci l'rcn‘e fabrl ation. Al mixture and to sodium and since its flowability s ~ characteristics are better than those of Nicrobraz, The alloy is applied as presintered rings, which to. prowde more favorable stress distribution, . " The torch used in semloufomchcally weldmg 'rher ltubeoto-header joints of one bundle is shown in iFlg. 6.14, whlle the header, mcludmg the stronge ‘:backs used to mmlml'e"dxsforhon durmg weldmg,' Icfer stage of fdbrlcuflon in Fig. 6.15. ’ A modlflcatlon was also ‘made in fhe pressure-' ik ::::adequofe corrosion resistance to both the fluoride PERIOD ENDING SEPTEMBER 10, 1955 UNCLASSIFIED Y«16104 SINTERED RINGS GRAPHITE MOLD & Fig. 6.13. Graphite Mold Used to Produce Sintered Brazing Alloy Rings From As-Received Powder. are shown in position on the underside of the heat exchanger header in Fig. 6.16. These rings can be secured to the header during assembly of the tubes either by electric-resistance spot welding or by using a volatile organic binder, Figure 6.16 also shows the diagonal comblike spacers installed on these units to assure uniform spacing between the tubes and to increase the rigidity of "rjh'e _bundle. Cornell Radiator No, 2 P. Patriarca G. M. Slaughter Me’ra”urgy DIVISIOn ~ R.L. Heestand Prcfif & Whlfney Alrcraf'r A second hqu:d ‘metal-to-air radlcltor, de5|gned by the Cornell Aeronautical Laboratory, has been fabricated, This construction problem was very 5|m|ldf to fha'r described prevmusiy, except that one header was not attached to the side plates and was thus free to ‘‘float” during thermal 81bid., p 139. 135 LR ANP PROJECT PROGRESS REPORT UNCLASSIFIED" CYaTeezs Fig. 6.14. One Header of the Intermediate Heat Exchanger No, 3 Tube Bundle After Welding of the Tube-to-Header Joints by Semiautomatic Inert-Arc Techniques. Masking tape was used to ensure adequate shielding-gas protection ot the roots of the welds. expansion and contraction of the assembly. The radiator core, with the floating header at the bottom, is shown in Fig. 6.17. The side plates and remaining header sections were welded to the core shown in Fig. 6.17, and the tube-to-header joints were back-brazed with ~ Coast Metals No. 50 alloy. Leak testing with a helium mass spectrometer indicated that all welded and brazed joints were leaktight, 136 UNCLASSIFIED Y-16061 Fig. 6.15. Improved Header Design of Inter mediate Heat Exchanger No. 3. Strongbacks were used to minimize distortion during welding. NONDESTRUCTIVE TESTING R. B. Oliver J. W, Allen K. Reber R. W. McClung Metallurgy Division The recent successes of several AEC instal- lations in the use of eddy currents for testing aluminum shapes suggested that the technique might be applied to the inspection of Inconel and stainless steel tubing. A comprehensive literature and patent survey indicated that the eddy-current flaw detection method had been successfully applied to magnetic materials and to high-conduc- tivity nonmagnetic materials but that little success PERIOD ENDING SEPTEMBER 10, 1955 - w},“‘ : Fig. 6.!6:..' lnfermedxafe Heat Elkehan'gerrNo.Lg Tube Bundle Showing Coast Metals Alloy No. 52 Brazing Alloy Presintered Rings for Back Brazing in Place on Under Side of the Header and the Combiike Spacers for the Tubes. - hvfly nonmagneflc a“oys. Laboratory"kwork with md]c__a_'red “however, LA R = A hrough an encnrcimg coil fh'an |t |s 'ro cause a S __equipment has_ ¥ i that there are good ‘pos'SIbllmi fa|r he sucaessful se “of eddy-current fechmques Tl fuBe, the"inlhal emphasns has been placed on the N St e 2 nc1rc||ng coils.’ Since the‘magmtude\cf the eddy current in a So ARy fparhcuiar plece of ma'rer:al is dlfectly proporhonal “of filncronel tubing. " :;ln brief, thew Vrii‘éthad' consists ‘in exciting eday ‘ =t “_H_[nspec'fed by bringlng f a éonl whlch sensmv:fy “of any eddy-curren’r' instrument varies “with the frequency\” 1t has also been found that to T e ;obfaln adequate sensmwfy, flght coupllng between and 'rhe tubmg must be malnfalned A lmpedyance e el ‘in the h.—-“ - s 2 AT tube that changes the magm’rude or fl;e d:strnbuhon - - SRR o S et of the eddy curren the impedance of the coil and moy be measured. currents in the tube wall, The relative magnitudes Itl i i ' Coils that encircle the tube and very small “‘probe” of the eddy currents at any depth x in a tube n 4t"fi‘e sensitivity ‘ ts is reflected as a change is the “skin effect” of the eddy - 137 kL ANP PROJECT PROGRESS REPORT UNCL ASSIFIED Y-15160 Fig. 6.17. Core of Cornell Radiator No. 2. wdl_l may be expressed by: i x - e_x\f‘TTfp,)t , Isurfo;e w‘_h'er'ef L f = frequency “permeability, conduchwfy. =" Ii It For Inconel, e elaionship s T x. surface - o Inconel -5 Hx\/_x 107 whlch mdncates thcn‘ 'rhe frequency must be limited if the eddy currents are to penetrate to the inside ,wall of the ?ube._ The choice of frequency is thus 'a compromise tho'r must be made for each tube (for x in mlls) : 138 ‘size and material, The frequency selections for : testing Inconel tubing are given in Table 6.8 . An impedance diagrom for a tightly coupled : coil encircling a Y%-in.dia Inconel rod is shown in Fig. 6.18 (sohcf curve through open circles), The frequency of the current (m kllocycles per ' E TABLE 6.8. OPTIMUM FREQUENCIES FOR EDDY-CURRENT FLAW DETECTION IN i INCONEL TUBING b Outside Diameter Optimum Maximum Inspection of Tubing Frequency Depth F (in.) (ke) {in) .' 3 0.20 500 0.030 to 0.040 b 0.25 320 0.035 to 0.050 ‘ 0.375 140 0.055 to 0,075 0.50 80 0.070 to 0.100 oy 1.00 20 0.150 10 0.200 UNCLASSIFIED CRNL-LR—DWG 8240 1.0 0 'WLA;COIL IMPEDANCE ALONE % = REACTIVE COMPONENT 0.9 %-RES!STIVE COMPONENT_ FILLING FACTOR=0.85 20 0.8 © INCONEL ROD VARIABLE FREQUENCY o IN KILOCYCLES { 53 I \ / ® INCONEL TUBING M dso ! WALL THICKNESS > EFFECT OF | #., IN MILS VARIABLE 07 — COUPLING 4 INCONEL TUBING ' mAbllTL%CCENTRIC]TY 0 \ Y oo\, s o | 7h0EL 9 \\;7\20; o 150 \ \\:-—5-2_ 0.6 AN —= T \ 400 0.5 0 X o2 03 04 AR - Wig Fig. 6.18. Normullzed |mpedunce Plune for ‘/- - in.-dia Inconel Rod or Tubing Obtumed wnth an_ Encnrclmg Coil., w o SRR - Selecfed (manufactured y Efecfro CII‘CUI‘I’S, Tne.y second) is shown for each point. If a particular frequency is chosen (80 kc/sec) and the effect of varying the wall thickness of an Inconel tube is investigated, the impedance curve will follow hrough the pomts indicated by the open squares, Hence, if / in,~dia, 65-mil-wall, Inconel tubing were being exammed the change in the resistive component would be a sensitive measure of a change in wall thickness, However, changes in eccentricity also produce changes in the resistive component, as shown by the curves through the triangles. Thus, in order to interpret the measure- ments in terms of the nature of the tubing flaws, both the changes in the resistive and the reactive components must be measured, There is no instrument available at the present time which will moke an lmpedance type of analy51s over the wide range of frequencies indicated in Table 6.8. Work with experimental equnpment has :ndlccted however, that such an instrument is feasible but would require con- snderable development work. As a result,emphasis is now being placed upon the development of su:table probe-type coils with which impedance anulyses could be made without changing frequency for each different size of tubing. In addition, it is felt that a probe coil, because of its small size, would be more sensmve to small flaws than would an encnrclmg coil. Since the eddy-current flaw-detection method ~ has many more unresolved problems than does the method that employs ultrasonic equipment, the " latter method has been chosen for the inspecflon of smc“-dmmefer tubmg. The uh‘msomc equ:pmenf - FATE SR gives very" clecm flaw s:gnafs ondiflhlghfresoluhon The~ ultrasonic_“equipment has crmlluNiT capable of detecting flaws which ore os “small” as pin “holes and which penetrate no more than 0.003 in. below the outside surface. All defects on the outer surface of the tubing that can be PERIOD ENDING SEPTEMBER 10, 1955 located by dye-penetrant inspection have been located with ultrasound. Alsa, subsurface defects of equally small size haye been detected with ultrasound and verified by metallographic exami- nation. Experience indicates that defects located on the inner surface will be similarly detected. The conventional presentation of ultrasonic ~data is on a cathode-ray tube as the ‘*A* scan, the vertical sweep being the signal strength and the horizontal sweep being the distance (travel time) from the crystal. This presentation is not interpretable at high scanning speeds, since the repetition rate of the flaw signals will be in excess of 100 times per minute. Gated alarm signals would also be unsatisfactory, since all spurious signals, as well as flaw indications, would pass through the gate, The less con- ventional ‘‘B*" scan would present the defects as a standing image of the tube cross section on a 17-in. cathodesray tube. In this case, the vertical sweep would be a scan of the ‘A" type of presentation, and the horizontal sweep would be the rotation of the tube. A ““B’* scan pattern from a tube having only one defect in the particular cross section being scanned is shown in Fig. 6.19. The defect, which is represented by the diagonal line, was a non- metallic stringer about 0.001 in. in diometer and about 1/ in. long. This defect was longitudinal and was located about 0.010 in. below the outer surface of the tube and paralle! to the tube axis, UNCLASSIFIED " UYa16274 Fig. 6.19. A ''B’’ Scan Oscilloscope Trace of a Tube. 139 Mechanical ‘equipment to rotate the tubmg cnd'” to produce a relative linear motion between the : tublng and the inspection device is being designed. This scanner will permit rapid inspection of -fubmg, and, if it is found to be des:rable, eddy- current and uh‘rasomc methods can be ‘used 's:multaneously. The use of the “B’ scan ~ requires an accurate signal from the rotation of ‘the tube, and one of the major problems in the design of the scanning equipment is that of ob- - tammg thxs s:gnal ' . C E Curhs J. R. Johnson J. A_Grn‘fm AL Taylor e Meta“urgy Division | Gruph:te-Hydrogen Corros;on-Eros:on o LR Inveshguhon ' Graphlfe-hydrogen ‘systems at tempercfures of . the order of 2400°C or higher are of interest for nuclear rocket applications. An investigation was carried out to determine whether hydrogen flowing at a velocity of Mach 0.15 in high-density graphite tubing (]/ in, OD, 1 in. ID, 24 in, long) at’ approx;mately 2400°C caused significant corrosion-erosion of the graphite. Two types of graphite specimens were used: Graph-i-tite (density, ~1.8 g/cm3), supplied by Graphite Specialties Corporation, and commercial graphite (density, ~1.55 g/cm3), A schematic drawing of the apparatus used for the high-temperature graphite-hydrogen experiment is shown in Fig. 6,.20. The graphite specimen was heated electrically to 2400°C, and a nitrogen or helium atmosphere was maintained in the specimen until equilibrium conditions were reached. The high-velocity hydrogen was applied for 10 min, ~and then the hydrogen was replcced ‘with helium “while 'rhe specimen was coohngr Data and resulfs “of the experlmenfs cre given in Table 6.9. The average corrosion-erosion for the tests on Grcph-:-hte showed a loss of 0.0001 g/m. .sec, It was noted that the we;gl-n‘ losses were about ~ the same wn‘h hel;um as wn‘h hydrogen, and I1‘ !S -.’rprobable 'rha'r ‘the losses were due to water vapor - _inthe gases, The bulk temperature of the hydrogen - was believed to be about 1600°C, and the velocity L was about 1900 fps, or approximately Mach 0.18. ‘It was observed that the weight losses of the o commercial grcxphn‘e were somewhat greater that . f"fthose of fhe Graph-l-hfe. ‘ Rcre-Earfh-Ox:de Confrol Rods R Two confrol rod cssemblues, snmlar to those prepared previously,? were fabricated for critical experiments from a mixture of rare-ecr’rh oxides containing 63.8 wt % Sm ,0, and 26.3 wt % Gd203, the remainder being prlmarlly other rare-earth oxides., The firing temperature of 1550°C for these shapes was 50 deg higher than that previ- ously used, The annular specimens were all 1 in. long with either 0.125- or 0.250-in. walls, The 0.125-in.-wall specimens were 1,275 in, OD CERAMl(.;. .R.IVESEJ;RCH L e gnd T.005 in, 1D, and the 0.250-in.-wall specimens o were 1.275 in, OD and 0.775 in. ID. Figure 6.21 shows samples of the fmlshed shapes. Calc:um Fluonde und Alumrnu Deiecfor Spucers Flux detector spacers of calc:um fluonde and aiummc were produced in 'rhe form of wafers "0.190 in. thick and 0.800 in. in dlcmeter, ‘with an indentation 0.12 in. deep and 0.747 in. in diameter. Reagent-grade calcium fluoride was precalcined at 1140°C and ground to pass a 200-mesh Tyler screen; 2 wt % Carbowax 4000 was added as a binder and lubricant. The wafers were pressed in a hard, steel die at 50,000 psi and then sintered at 700°C for 1 hr. The alumina wafers were pressed similarly from fine-grained A|203, without calcination, and then sintered at 1350°C for 1 hr, Fluoride Fuel Pellets The optimum pressing conditions for pelletizing fluoride fuels in convenient shapes for loading into a reactor are being studied. A pressure of 4000 psi was not sufficient to produce pellets of NaF-ZrF ,-UF, (50-46-4 mole %) that had adequate sfrength ngher pressures are bemg used in experlmenfs now under way. . Synthesis of Boron Compounds Ah'invesf-igat‘ ion of the fecmblll'ryofsynthes:zmg T Mo,B. and B,C has been started, These, com- pounds are of interest as sh:eldmg “material. Several samples of MogB have been prepared and 7Tk are being analyzed. Samples of B - 4 by heating a stoichiometric mixture of boron and carbon to 1750°C. It is anticipated that about_ 100 tb of B10 will be made into B C 1955, ORNL 1896 p 145. 9J A, Griffin et al.,, ANP Quar. Prog. Rep ]une IO C were made |} TABLE 6.9. RESULTS OF GRAPHITE-HYDROGEN CORROSION-EROSION EXPERIMENTS Surface Temperature Surface Temperature LLocation of Thermocouple Total Weight bReoding_.obfained with optical pyrometer sighted down sight tube (see Fig. 6.20). “Reading obtained with optical pyrometer sighted down exit tube (see Fig. 6.20). Rund Gas in Gas Flow Time Between of Graphite Specimen of Graphite Specimen Maximum ¢ Which Maxi G | Moeximum Graphite Power Input L ¢ Nun Graphite Rate Temperature at Beginning of Timed at End of Timed Temperature of Gas Trom :c v::xlm;;: ) asd "E‘ipecimen Temperature to Specimen s os's ° o Specimen (ctm, STP) Readings (min) Period Period cC) emperature i as aine ! (°Cye (kw) pecimen (OC)b (OC)b : (see Fig. 6.20) l (g9) Specimen: Graph-istite (0 = 1,8 g/Cm3) | 2 Nitrogen 14 20 2245 ) 1 8.7 Helium 18.6 13 2110 1935 f | 3 Nitrogen 41 20 2260 i Helium 9.6 16 2255 2230 10.7 3.3 Hydrogen 16.2 10 2230 1830 ' 4 Helium 10.8 33 20 2250 109 1.6 Hydrogen 12.2 10 2250 2220 _ * * 5 Helium 9.6 28 20 2205 } | Hydrogen 11.2 10 2205 2090 . 11.0 1.8 6 Helium 8.8 10 2240 2035 E 11,2 1.4 Helium 4.7 17 20 1500 650 A ) ‘ - 1190 B 14.5 5 ISOQ 1860 590 A > 2450 ‘j‘_: 12.1 1.1 Thermocouple melted B o ' 9.4 23 1860 2250 840 A Thermocouple melted B / 8 Helium 4.6 19 20 2155 1540 C 3 . 9.6 10 2155 2210 850 C Hydrogen 2.8 5 2210 815 C > 2400 8.8 1.7 6.5 3 970 C W 4.9 2 2200 1120 C J 9 Helium 5.5 28 20 2160 1770 b 10.1 12 2160 2220 1770 F 2350 o 9.3 0.8 Hydrogen 13.3 9 2220 Thermocouple melted ’ 9.8 1 2270 10 Helium 4,3 35 20 2020 2450 9.4 6 2380 2.3 4.1 : Hydrogen 11.7 10 2250 ' Specimen: Commercial Graphite (p = 1.55 g/Cm3) " Helium 4.6 19 20 2210 11.3 12 2210 2285 2380 L 12.2 4 2285 9.3 3.3 Hydrogen 9.8 1 9.8 9 2025 12 Helium 5.6 15 20 2210 - 9.2 15 2210 2305 2530 10.8 6.0 Hydrogen 8.6 10 2260 s “Run 1 was for checking apparatus, 141 1 "w ESE Wi % UNCLASSIFIED ORNL~LR-DWG 8944 A,B,C,D,E AND F REPRESENT THERMOCOUPLE POSITIONS FOR DIFFERENT RUNS (SEE TABLE 6.9) GRAPHITE EXIT TUBE -+ | FIREBRICK WALL CARBON BLACK FILLS 18~in. OF 20-in. DEPTH GRAPHITE SIGHT TUBE GRAPHITE SPECIMEN WINDOW - & 3,-in, WATER-COOLED A STEEL PIPE COPPER BLOCK p2 Fig. 6.20. Apparatus for High-Terfipefuiure Graphi‘fe-l'lydr'ogen Corrbsion-Erosion Expetiment, Fabrication of Dysprosium Oxide Disks The fabrication of dysprosium oxide, which is of interest for use in medsuring thermal flux in a reactor, is being investigated by the American Lava Corporchon under an ORNL subcontract., ”Dlsks '0.242 in. in diameter and 0.011 in. thick Tty T, that contam approxlmately 1 fng of dysprosnum 'md T ¢ and the flller is electrlcu“y fused AlLO and finer, and a purlty “of about 99.5%. The principal contaminant is Si0,. These disks were submitted to the Critical Experiment Facility for evaluation of léfire;.E‘.c:ri.B- ' Fabrication of 'Europium- 7.(')..xide Waifér-s‘ | Fié. 6.21, Annular Speéimens; ‘Oxides (Sm,0, and Gd,0;) for Control Rod As- A preliminary investigation has indicated that semblies. wafers 3{1 in. in diameter and 0.030 in. thick, 143 oxnde per squcre cenhmeter of area have been - prepared “The disks contain ‘an organic resin e WEEer g e L T e FFrmEY R . to the MTR for abouf ]02]-nvt exposure. ANP PROJECT PROGRESS REPORT prepared from Eu,0, powder by preealein'ing at 1200°C for 1 hr, cold-pressing at 20,000 psi, and sintering at 1500°C for 2 hr, are unstable in the presence of moisture, Similar specimens prepared from uncalcined material cold pressed as above and smtered at 1200, 1300, 1400, and 1500°C for 2 hr showed no signs of breakdown in the "'presence of moisture. As soon as suitable speci- “mens' have been prepared, they will be submlfled 4 SPECIAL MATERIALS STUDIES ~J. H. Coobs J. P. Page - H. Inouye T. K. Roche ' Metallurgy Division ©r ot Mo R, D’Amore = Pratt & Whitney Aircraft B ~ Columbium Research The investigation of metal diffusion barriers ~ for use in the fabrication of Inconel-clad columbium sheet was continued, » ‘ported, 0 the interdiffusion between Inconel and columbium at elevated temperatures is extensive. The reaction products, which appear to be nickel- columbium compounds, are brittle, and, because of the difference in the coefficients of thermal expansion between the metals, separation occurs af the interface when the composite is cooled to room temperature, The problem is not that of preventing the formation of intermetallic compounds, although this would be desirable, but primarily that of selecting a suitable combination of metals which will remain thermally bonded in service. This is mandatory, since the composite is being considered for use as a heat transfer surface, The barrier metals to be studied were selected somewhat at random, since the phase relationships between columbium, the possible barrier metals, and Inconel have not been thoroughly determined, especially as to the nature of the compounds which are formed. Vanadium, titanium, molybde- num, tantalum, and copper have been evaluated as the barrier metals, _ Composites were fabricated by hot-rolling capsules which had been evacuated at 1100°F to at least T x 10~4 mm Hg. Rolling temperatures between 1800 and 2100°F were used at reduction oo _]0.1. H. Coobs, H. Incuye, and M. R. D’Amore, ANP o .Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 140. As was previously re- schedules of 30 and 40% per pass. The total reduction in thickness was about 5/1. No particular effort was made to predetermine the thickness of the columbium core or the Inconel cladding. A final composite thickness of 0.020 in. was evaluated. The barriers were calculated to be 0.001 in. thick after being rolled, Cross sections of strips that had been bent fo form an involute of a circle were examined microscopically, " The Inconelevanadium-columbium composite in - the as-rolled condition withstood several 90-deg 'bending reversals over a sharp rudius. M:croscoplc ‘examination showed a reaction layer at the vanadium«|nconel interface that was less than '0.0001 in, thick, The reaction layer was cracked - perpendicular to a tangent to the curved surface. ‘Since no separation occurred at the interface, this composite could probably be formed to a desired shape by cold spinning. After 100 hr at 1650°F, the composite separated at the Inconel-vanadium interface upon bending, The reaction layer at this interface had increased to about 0.0005 in. in thickness, and the vanadium layer had decreased in thickness. After 500 hr at 1650°F, the composite separated during sectioning. Microscopic exami- nation showed that the vanadium layer had been completely transformed to an intermetallic com- pound, An |Inconel-titanium-columbium composite was found to be unsatisfactory because of the formation of a low-melting compound at the rolling tempera- ture of 2100°F. The compound was brittle, and separation of the composite occurred during cooling. The experiment is to be repeated with a lower rolling temperature, An Inconel-tantalum-columbium composite was prepared, but, since tantalum and columbium are isomorphous in several aspecfs fhe composn‘e" was not expected to be successful. Specifically, this combination was tried to determine the effect of the melting-point difference of the metals on their diffusion rate with Inconel (columbium melts at 4380°F; tantalum melts at 5425°F) It was - also desired to compare the proper’rles of The expecfed reaction products, ' - Examination of the composite after rolling at 2100°F showed a 0.0001-in.-thick reuchon Iayer at the I[nconel-tantalum lnferface, which ‘was ‘found to be brittle at room temperature. However, separation did not occur after numerous 90-deg bending reversals. In the unbent position, the e ~ metallic compound - under ’rempemrure cychng. WL o ?festmg the creep s'rrengrh of _ofh el , 7" columbium. This mformahon is needed for de- “termining whether columblum may be wbshtutedimt Wlncone[ in an ART-typeMW - ussembly and have strengrh equal to or greater “than that of !nconel alone. ~ Other tests will be 7 ‘which barrler 'ma'rerlcl copper”” : N_or fcmmlum, IS beh‘er su:ted for 'rhls apphcatlon.h_‘ ‘Investigations of copper as “the bcmer materlai:""_ "'fwere reporfed prev10us|y 10 Tantal ‘ | ‘_dlsadvanfage of havr Gfron cro oy " made to determme " width that will permit the welding of totally clad ++ columbium without serious heat damage to the ST _mterfoce. - composnfe showed no crccks in fhr= reachon layer. During service tests at ]650°F fhe recchon layer ;between the tantalym cmd ‘the Inc | ""'w:th time, until in 500 hr abou__ mcreased the rantalum had bee_n converted to cm inter- The rantclum-columb:um mferface showed no fendency to dn‘fuse at these . rem percfures . Bendlng-reversal 'res'rs ‘mode qfrer 500 hr at 1650°F resulted in no seporahon in the composne,“ ' even 'rhough ‘the reachon layer cracked perpendicu- lar to a tangent to ‘the curved surface. No cracks were observed in the unbenf portion of the com- posn‘e.' It may be possuble 'rherefore to form ’rhe‘-f |ncone|-tantaIum-columblum . composne “in the 'qs-rolled condmon and to mamtmn rhermal bonds‘:‘ Addmonal experlments are being desrgned for for a large porhon of th m. of “and unclcdi R PERIOD ENDING SEPTEMBER 10, 1955 In a preliminary investigation of Cb-UQ, fuel elements the compatability of UO, and columbium 'wcs' studied at 1500 and 1832°F for 100 hr. The specimens ‘were prepared by hot swaging 20 wt % ‘U02 with columbium powder at 1742°F. “Both ~steam-treated UO, and high-fired UO, were “used for these tests. The mixtures were exommed in the as- -swaged condition and after the 100-hr heafmg period. Under all test conditions a third phase, which was pinkish in color, was found in the matrix., This phase appeared as discrete particles or as a portion of a former UO, particle, and the quantity of this phase increased with heating time, Xeray patterns of the tested mixture indicated that a solid solution of columbium- uranium was present. The same phase was found gs a network in an arc-melted button of a 5% . Cb-95% Ualley. -_.r.mcomposlte Tublng Fabrlcohon Ex'rrusron experlmen'rs for preparmg two- and .';rhree-piy seomiess tube blanks have been con- _‘tmued As in prevnously reported experiments, the layer compositions for these experiments 10 were carbon steel and type 316 stainless steel, ;The Two-ply extrusions were carbon steel clad on . the outside with stainless steel, and the three-ply _,extrusmns were corbon s’reel c!ad on both sides _,.,.>_.“wn‘h stamless s'reel o= When équal sforhng fhlcknesses were used in i previous experlmenfs, the ihlckness of fhe extruded qlso served as markers to outline the deformatlon pattern. In addition, the markers outlined the ]/2-in.-fhic|< disks and thus served to determine 145 o s bies i ANP PROJECT PROGRESS REPORT the final shape of the disks when théy were used in three-ply exfrusmn. Both flcn‘-nosed and 45-deg tapered dummy blocks were used in front of equal thicknesses of concentric rmgs.' In the two-ply extrusions, devu:mons in thickness were about 15%. The ‘inner layer in both extrusions was thinner than desired. In the three-ply extrusions, the inner cladding was thinner and the outer cladding !’rhlcker by 15% than had been calculated. The ‘ "core of the extrusion showed no deviation from the calculated thlckness.' The results obtained . to date in attempts to extrude concentric layers . _of equal fhlcknesses ore summarlzed in Tqble 6 ]0. _"_‘:__i'-:were sechoned lengfhw:se and examined. The " "'deformaflon across the tube wall was complex, since both compression and tension were evident. Tensile forces prevclled in the outer and inner layers, while compression forces prevailed in the zone in between. The original 0.010-in.-thick molybdenum washers varied in thickness from about 0.003 in. near the tube walls to 0.050 in. at the middle of the tube wall, The displacements of the mo[ybdenum washers from their starting positions were noted. After extrusion, the washers could be located as coordinates of a parabola of revolution, with the axis being the center line of the tube. The shapes of the separate washers differed along the length of the extrusion. It is evident that because of the tensile forces near the tube walls the flaws in this zone in the starting billet will result in flaws in the extrusion, TABLE 6.10. RESULTS OF ATTEMPTS TO EXTRUDE CONCENTRIC LAYERS OF EQUAL THICKNESSES o Oxidation Tests of Alummum Brouze - The aluminum bronzes are bemg considered as cladding material for the oxidation protection of copper fins for radiators, Therefore oxidation tests of several commercial bronzes were conducted in air at 850°C. The weight gains of the alloys as a function of time are shown in Fig. 6.22. Lead-Calcium Alloys The chemical-analysis technique for evaluating the creep resistance of lead-calcium alloys was investigated. It was determined that chemical analyses were not indicative of the creep per- formance of these alloys, because the normal scatter of the data on the calcium content frequently exceeded the desired calcium content of between 0.03 and 006%. The strengthenmg effect of calcium can be realized only if it is present in solid solution or as a compound with lead; that is, if a portion of the calcium is presem‘ as Ca0, the beneficial effects of the calcium are lost, Since the chemical analysis gives the total calcium rather than the CaO content of the alloy, the chemical analyses can serve only as a guide in the evaluation of the creep performance. For example, three alloys calculated to contain 0.06% calcium on the basis of analyses of three master alloys containing 2% total calcium were found by chemical analysis to contain 0.043, 0.030, and 0.059% calcium, respectively. In cantilever creep tests at room temperature and 750-psi stress, the deflections of these alloys at the end of a 2-in. beam were 0.87, 0.33, and 0.54 cm, respectively. Since the chemical anclyses defermme only fhe Tubing Type of Dummy Block ~ Average Layer Thickness Length of Extrusion Containing Uniform Layers Used Inside Layer Core Outside Layer (@) e o Two-ply . None 0.087 0.132 T 45 T ; CLE 7 Flat nosed 0.109 0.140 - éa - - h 45;d?g'-fapered ' 0.107 0.1 18" o Ce6 T - : Three-ply Norne 0.050 0.073 0.111 s St Flatnosed 0,070 0.074 0.103 Css .. 45-deg tapered © 0.078 0.075 0.104 56 .y ) PERIOD ENDING SEPTEMBER 10, 1955 UNCLASSIFIED ORNL-LR-DWG 7388 T T T T T T 10 |- MATERIAL COMPOSITION (wt %) : e W W ALLOYS 5.4 Al—~BALANCE Cu 02 =10 712 ALLOY 4.33 Al-1.22 Si~BALANCE Cu A DURONZE NO. 4 6.2 AlI-0.21 As~0.2{ Zn—BALANCE Cu 08 = [ A AMPCO NO. 8 9.49 Al-1.94 Fe—BALANCE C — mO : - .__..—-—""'"'_——_ : o7 . .—-—-‘,—" /___.—"O —_ ' § < o0s ' e | AT s “ P —— / /%’ M“'"&- A 0 : 0 0 10 20 30 40 50 60 YO 80 90 100 110 120 130 440 150 160 170 4180 190 200 210 ELAPSED TIME (hr) Fig. 6.22. Oxidation of Commercial Aluminum Bronzes in Air ot 850°C. total calcium, the master alloy must be made under conditions in which the oxidation of the calcium will be held to o minimum, It might be possible to improve the accuracy of the alloyed calcium determinations by filtering the master alloy at about 1475°F through a quartz filter prior to analysis. , About 150 Ib of a lead-calcium alloy containing 0.05% calcium was‘.sppphed to WADC for elevated- ifemperature U epw' fes'rmg." Chemical enalyses e alloys ~ “reduce the neutron flux through it about 90%. Since such a relahvely thin layer would meet "»'“eoctor spec:f:cahons, if therma”y bonded to the ~Inconel, experiments for depositing boron by _‘ electrophores:s and electroplatmg of boron slurrles are being contemplated Unbonded tiles ot sfrtps “of boron compounds in a metalllc matrix " would then be used to fill the remaining space of + the ¥%-in. annulus provided. N “contenfrs of t T material is bemg studied, A material contommg a" minimum of 1 g of boron per cubic centimeter of a metallic matrix is to be bonded to a l/4-in.-th'icl< Inconel hemisphere. The initial experiments were prepared from “had” been profected from . were attempts to obtain thermal bonds by flame- spraying mixtures of Cu-B,C. The results, to date, do not appear to be promising, since a large proportion of the B, C is lost during spraying. in other experiments, attempts were made to wet B,C with copper alloys and to cast the resulting slurry. The oxidation of the B,C to B,0, during melting appears to be a ma|or problem in this opprouch The experiments are fo be continued in an inert ‘atmosphere. A |ayer equwalent to 0.008 in. of boron will Adisk and a ring were fabricated from a boron '_ eerblde—copper mixture for use as neutron poison “in the high-temperature critical assembly. The disk was to be 63/ in. in diameter and 0.500 in. thick; the ring was to have an outside diameter of ]2]4 in., and a cross section of /16 X ’/‘, in. 147 ANP PROJECT PROGRESS REPORT The disk was formed by pressing a mixture of B,C and copper powder in a graphite mold at 900°C, and it was found to be 6]/2 in. in diameter “and 0.447 in. in average thickness; it contained 0.367 g of boron per cubic centimeter, or 97.4% of the theoretical density. The disk was machined _to 6% in. in diameter with diamond tools, and diffusion barriers of copper and stainless steel were applied by flame-spraying. ~ The barrier _layer thicknesses were 6 and 15 mils, respectively, '~ Attempts to fabricate the material for the ]2Z-in.-0D ring by extruding a billet of compacted B ,C-Cu powders canned with copper were unsuc- cessful. Severe edge cracking of the material | _}48_. - occurred during extrusion and was probably due to either too high an extrusion temperature or too thin a copper can, After the unsuccessful extrusions, the ring was fabricated by drawing a round copper tube filled with B,C powder into a rectangular tube with a % . x % in. cross section, The tube was then roll-formed to a IZZ-in.—OD ring and split into two equal segments for ease of assembly., The open ends of the tube were closed with boron carbide—copper plugs. The ring contained approximately 2.25 g of boron per inch of length. A 7-mil layer of type 430 stainless steel was flame-sprayed onto the ring to act as a diffusion barrier, PERIOD ENDING SEPTEMBER 10, 1955 7. HEAT TRANSFER AND PHYS!CAL PROPERTlES o & A s 0 H F Poppend[ek Rec:cfor Experlmental Engmeermg Dlvns:on { - Forced-convectlon heat trqnsfer expenments ('l] 2—4]-45325 mole %) flowmg in a heated ‘ ' wn‘h the fuel mixture ‘NaF- KF LIF UF, flowing in Incone! tube gave results which were 40% below ..~ S a heafed tube were conhnued and heat transfer the general turbulent-flow heat transfer correlation. f " and friction charactenshcs of a full-scale ART These results (Fig. 7]) have been duplicated : ' , _hea'r exchanger were determined. Flow pcrh‘erns in recent experlmenfs in whxch a type 316 stainless E . . in models of the 18- and 21-in. ART cores have steel tube was used. It was not possible to : been determmed for rofoflonai and axial flow, as examine the inside surfoce of the stainless steel 3 well as various en’rronce condlhons, ‘and the tube, because the experiment was terminated by ‘ . results are summarized. The ’remperature distri- the melting of the test section, However, it is F { . butions within fluids flowmg through converging believed that there were probably no surface and dlverglng channels “were determ:ned experi- depos:fs on the stamless steel tube, which was 1 mem‘a”y in the volume-heat-source system. the same case in earlier experiments with : The em‘halples and heat capacmes of LiF-KF NaF-KF-LiF (11.5-42-46.5 mole %). Thus, the - S (50-50 mole %) were determined, and the vuscosmes' reduction in heat transfer obtained with this E o T of elght fluoride mixtures were measured fluoride mixture is probably due to something 1 { FUSED SALT HEAT TRANSFER =+ other than the formation of surface deposits. UL S S Some evidence exists which indicates that the N _ H W. Hoffman P E. Stover NaF-KF-LiF-UF | composition contained particulate E s Reactor Experlmental Englneermg Drv;s:on B matter that made it a dilute slurry. However, s Prev:ous forced-convechon heat h'cnsfer experl- before any conclusions can be reached as to the 'y '-“">","'-""ments with the fuel mixture NaF-KF- LIF-UF4 effect of this feature on heat and momentum } ooi0 A e o o ORNL-LR-DWG 8942 o] B G NoF-KF-LiF —UF, IN INCONEL S ® NoF-KF—LiF—UF, IN TYPE 316 STAINLESS STEEL A4 Hy0 IN TYPE 3{6 STAINLESS STEEL g " |- GENERAL CORRELATION L i » =T T 2 /=0.023 Mg 02 LT AT ‘s 7 | S L A T , Lo EL A 3 i 4"‘,' L o ; _1‘ ) :F.ig.r 71 Compunson of Heat Trunsfer Meusurements on NoF KF-LiF- UF, (11, 2-41-45 3 2.5 mole%) and l AR Wm‘er w;th the General Correluflon for Ordmury Fiuxds. 149 " ANP PROJECT PROGRESS REPORT transfer, further experiments must be made. Heat transfer studies in which a Hostelloy B test sechon is used are now in progress. As a check on the over-all performance of the _"experlmen’rol cppcra’rus used for these studies, the system was operated with water as the heat ’rransfer medlum. The water data, shown in ‘Fig. 7.1, are in ‘good agreement with the general ,:,‘_,"turbulent-flow _correlation’ and indicate that ~the low heat transfer values obtained with "‘NaF-KF-LlF UF are real. - consnderable scah‘er in the water results has not ye’r been determined. Assembly of a heat transfer system that includes S g pump is in progress ‘and will be completed in ~ ‘the near future, The system will be opera'red with "fwc'rer‘prlor to “studies with the salt ‘mixture NoF-ZrF UF (50-46-4 mole %). ART FUEL TO NaK HEAT EXCHANGER J L. Wantland Reactor Experimental Engineering Division For the recent experiments with the ART fuel-to- NaK heat exchanger! the tube bundle was heated by passing an electric current through it; water was circulated outside the tubes, but there was no fluid flow Through the tubes. The fuel heat transfer coefficients were determined by measuring tube-wall and mixed-mean-fluid temperatures, as well as heat transfer rates. As is shown in Fig. 7.2, the data obtained corroborated the heat transfer coefficients previdusly determined by using the apparatus as a water-sto-water heat exchanger. Also, the heat transfer and isothermal friction characteristics of the fuel side of the heat exchanger were determined with all the tube spacers removed from the tube bundie, except for one horizontal and one vertical spacer at opposite ends_.' In Figs. 7.2 and 7.3 the data are compared with previous data taken with all the spacers in the heat exchanger. As was to be expected, both the heat ftransfer coefficients and the friction factors decreased upon removal of the tube spacers, The difference is partially due to the spacers creating form drag and inducing some __additional turbulence, However, when the spacers ' were removed the tubes were not rrgldly held, and 15, L. Wantland, ANP Quar. Prog. Rep. June 10, 1955, © ORNL-1896, p 149, The cause of the “*channeling’” occurred in the flow pattern. The flow channeling increases the effective equivalent diameter (and hence the Reynolds modulus) and ORNL—-LR—DWG 8943 100 Nu/Pr%= 0.023 Re 50 20 Nu/Pro? S SPACERS e WATER-TO-WATER HEAT EXCHANGER 2 4 RESISTANCE-HEATED TUBE BUNDLE WITH NO FLUID FLOW THROUGH TUBES {000 2000 5000 10000 20,000 50,000 REYNOLDS NUMBER, Mg, Fig. 7.2. Heat Transfer Characteristics of the Fuel Side of the ART Fuel-to-NaK Heat Exchanger. ORNL-LR-DWG 89844 0.5 & S 0.2 g . b SPACERS 8 P 0.4 Q n lL- *0.05 T SPACERS LAMINAR FLOW IN A SQUARE DUCT. L= o 25 0.02 TURBULENT FLOW IN A SMOOTH DUCT 0.01 100 200 500 1000 2000 5000 10,000 REYNOLDS NUMBER, Wg, Fig. 7.3. 1sothermal Friction Characteristics of 'fhe Fuel Side of the ART Fuel-tosNaK Heat Ex- changer. decreases the efféctive surface area for heat transfer. Since the cmoun’r of channeling was not known, it was lmposs:ble to determme the effect of the presence of the spacers on fhe hecn‘ fransfer ' and frzchon characterlshcs. 7 ART CORE"HYDRODYNAMICS U FUE. Lynch o Recctor Experlmentcl Engmeermg Dw:snon ‘ G L. Mu”er Pra’rf & Whl'mey Aucrcuft Sfudies of fhe fiow feafures of a serles of one-_ quarter-scale ART core models have been under way for the past six months. The specrflc fypes of cores and flow condmons studied, as well as ‘the kinds of entrance condmons, are llsted in Table 7.1, The hydrodynamlc s'rruc’rures were - studied wnh quahfchve, as well as quanhfotwe, '7.'_techn‘|ques over the Reynolds modulus range 3,000 to 40,000. ln all cases, some flow sepa- L rohon, flow sfognc’non, or transnen’r flow conditions " were observed. In general, rotational flow yielded . flow separohon on the |sland wall, and axial How gave flow seporahon on “the outer wall vanes usually produced transient flow. PERIOD ENDING SEPTEMBER 10, 1955 Recently, two cores with constant spacing between the inner and outer walls were studied. One of these, in which the ratio of the flow cross- sectional area at the equator to the flow cross- sectional area at the inlet was low (1.44), was characterized by uniform and steady flow, Research on a variable-geometry diffuser has been initiated. A plastic housing for the flow system has been completed, and the templates for the channel are being designed. The flexible walls for the divergent channel are being fabri- cated, REACTOR CORE HEAT TRANSFER N. D. Greene H. F. Poppendiek L.D. Palmer Reactor Experimental Engineering Division The temperufure structures within fluids flowing through short, converging and diverging, plastic flow channels were experimentally determined in ‘the volume-heat-source system (Fig. 7.4). The heat sources were generated electrically by a high-voltage power supply. The channei walls, which were not cooled, were instrumented with thermocouples that were located about 30 mils _TABLE 7.1. SUMMARY GF ART CORE HYDRODYNAMICS STUDIES Core Diameter . | Type of Flow (in.) Entrance Conditions Flow Features 18 Rotational (45 deg} _Rotational No vanes or screens Wislicenus vanes " Flow Separotion on outer core shell Flow separahon on lslond Flow separation on island and flow transients ~ 151 ‘Flow sepqranon on outer core’ e it — . o o, W 7 Sl O e IR = g S ¢ E-'l‘. <. BX: BRI, KOOI PO .. a W X) . S A x a’ ANPANPS o ~ %, UNCL ASSIFIED PHOTO 24441 1¥0dIY SSIUO0YUd LIFr0¥d dNV v M " conditions of the experlmenf - profiles that make vp each of these flgures show below fl"ler_’s;d-rche. Some typical fluid and wall temperature distributions for the 16-deg diverging and converging chunnels cre shown in Figs, 7.5 and 7.6, which also give some of the specific The two sets of some typlcal femperature distribution extremes, It was possflole to make the following observations about the nature of fhe thermal structure in the uncooled chcnnels (1) “axial wall temperafure profiles exhnbn‘ed large degrees of asymmetry; (2) the wall temperatures fluctuated s:gnn‘:contly ‘with time, while the mixed-mean-fluid temperatures into and out of ’rhe test section, as well as fluid flow rates, were constant with time; and (3) the radial temperature differences for the convergent PERIOD ENDING SEPTEMBER 10, 1955 flow channel were greater than corresponding differences for the divergent channel. The first two observations were expected because corre- sponding velocity variations were observed in the . hydrodynamic field. The third observation was in agreement with previous temperature calculations ‘that had been made for converging and diverging channel systems. A one-half-scale model of the ART core is being designed for insertion in the volume-heat-source system. An electrode system has been devised whereby nearly uniform or sinusoidal electric flux fields can be generated in the flowing e[ec’rrolyte. Wall temperatures for the uncooled walls dre to be measured, In this way the influence of the complex hydrodynamic features of the flow on the thermal UNCLASSIFIED ORNL—LR—-DWG B945 46 . O O 45 : # / ‘ | } P / d 44 Of‘ /I o , /7 1° / / . / / /o 43 / P [/ P ! / / ] 7 7 . O / I /| / / /’ / 42 / Ld /o / . ) / / / . . / 41 7 / ’/ ‘/ / / 40 - A/ S § MIXED MEAN FLUID ,P d E ,l/f W _ /ly ——=— ONE WALL /9 2 39 : L / — = mw QOTHER WALL 0’/,/ / & / i , N ;?\,O/ / ‘ Re= {8,000 Pr=8 _ 5 / L Y LNO WALLCOOLING /( / ™ AN N Fig. 7.5. Experimental Temperature Structure in a Divergent Channel Huving'u Uniform Volume Heat Source. 153 'ANP PROJECT PROGRESS REPORT ST yNGLASsIRED " ieliliiere ORNL—LR—DWG 8946 S g e _ iz ORNL= > 89 e o \\ e \ (%‘ ks ‘l ~ A b 1 1’(5 O L N\ | A & v/ \o._\ ‘ \) \ A, ‘\ . ‘\ ’ N\ \ \ \ \\ \ \‘o\ - — v v—— d TEMPERATURE {°C) W fl / i : \ MIXED MEAN FLUID ONE WALL \ OTHER WALL ™ Re= 18,000 Pr=8 \ NO WALL COOLING — 34 \ TIME, 11:28 \ TIME, 14:28:30 \ ‘ 32 \ ) W«—/ 1 30 ' L POSITION Fig. 7.6. Experimental Temperature Structure in a Convergent Channel Having « Uniform Volume Heat Source. structure can be determined for a series of entrance conditions. ' A report has been prepared which describes applications to more general convection problems of previously developed mathematical temperature " solutions for forced-convection systems having ‘volume heat sources within the fluids. Convection " solutions are tabulated so that it is possible to determine the detailed radial temperature structure ~within a fluid having @ uniform velume heat source and being uniformly cooled at the duct wall; the detailed temperature profile of a specific system - is presented. The derivations of equations S dé‘sérrri_bing the temperature structure and heat .. transfer rates in a duct system in which the wall POSITION is nonuniformly cooled are also given, and the temperature structure of a specific heat exchange system is presented. HEAT CAPACITY W. D. Powers Reactor Experimental Engineering Division The enfhalpy- and the heat capocny of LiF-KF (50-50 mole %) were determined by using the copper-block calorimeter, The results are: Solid (107 to 466°C) Hp - Hyo o = -9.38 + 0.2817T + (3.82 x 10~5)72 c, = 0.282 + (7.64 x 10=5)T FETY T L) i LR AR, i i e 5 enmial+ e e sk s e o U MLEARAC || G s, AN L i sbmin L St ...wum‘ - el N » " _L'iqu'id (532 to 893°C) ) HT"H25°C = ~30.85 + 0.'583“-)"1“';(]0.28 o 10‘5)T2 = 0584 (20 56 x 10~ ")T2 f*- 93 Cfl' 4920(: " n \‘hese expressnons 25%¢ = enthalpy in cai/g, “p AH], = heat of fusion in cal/g, ' = heat capacity in cal/g-°C, T = temperature in °C, The facility for defermining heat capacities has been completely renovated, and it is now being put back into operation. Three copper-block calorimeters will be used in conjunction with four furnaces. Preliminary designs have been made for a furnace and o calorimeter to be used with beryllium- containing materials, Complete protection against exposure to beryllium will be provided. A report is being prepared that lists all the heat capacities and enthalpies that 'have been determined for the fluoride mixtures. General equations have been developed so that enthalpy and heat capacity predictions can be made. VISCOSITY S. 1. Cohen Reactor Experimental Engineering Division Viscosity studies were carried out on eight fluoride mixtures. The results are presented in Table 7.2 and in Fig. 7.7. Most of the data can be expressed in fhe form " cen pmses Cand T in °K7N where p. 15 . 4equahon :s hsted |»n Toble 7 2 f?F Sdlf C becau53\‘"‘:‘“; from an ‘avercge llne” through the= “data did nof""" ‘ 'exceed +12%) Sahs d, e [ and & which con- " “tained BeF., were studted in q separate dry box “Used only for BeF2 mixtures, Measurements were mcde on ’rhese salts with two capillary viscometers "to furnish checks. Salt g g appcrenfly had very high surface tension and nonwettmg properties and thus would flow through the capillary; consequently, 5 VISCOSITY (cp) PERIOD ENDING SEPTEMBER 10, 1955 no results were obtained on this mixture. It did not have the turbid appearance characteristic of other BeF, mixtures but was clear, glassy, and full of air bubbles. lts viscosity appeared to be high. The low viscosity values obtained for salt & suggested the possibility that research with . systems containing RbF might produce a satis- factory fuel with a viscosity lower than that of the zirconium-base fuel now being considered for the ART. Salt b, which is, approximately, a prototype of the proposed ART fuel, with RbF substituted for NaF, was therefore investigated, It was found to have a kinematic viscosity about 20% lower than that of the corresponding NaF mixture, Further research and the use of higher purity RbF might produce fuels with even lower viscosities. The results of examinations of seven fluoride mixtures containing BeF, are presented in Table 7.3. Salts 4, e, f, and g were studied at UNCLASSIFIED ORNL-LR-DWG 8947 TEMPERATURE (°K) 700 800 200 1000 1100 1200 © 400 500 600 700 800 900 1000 TEMPERATURE (°C) Fig. 7.7. Viscosities of Fluoride Mixtures. Compositions of the mixtures are given in Table 7.2, 155 | " ANP PROJECT PROGRESS REPORT 1 9 o . : 4 ~ORNL, and salts 7, j, and & were investigated at mixtures ‘previously studied. Salt i appears to be ] Mound Laboratory. Tabulated with the compositions the most favorable BeF, mixture, from a viscosity ; are the viscosities at '700°C and the BeF . content standpoint, that has been found thus far. |ts : j _in weight per cem‘ Figure 7.8 shows a plot of kinematic viscosity at 700°C is 1.84 centistokes, : 3 the viscosities vs the corresponding weight which is about equal to that of the NaF-ZrF -UF, j | percentage of BeF,, as well as the data for mixture currently planned for use in the ART. " TABLE 7.2. SUMMARY OF CURRENT VISCOSITY STUDIES Yiscosity Composmon '(rh'ol'.e'..%r) o 1 Reference NaF KE-LIF-UF, areoc, 5.8 0.0319 455877 (@ o (112-41-45 3-2. 5) . Ar750°C, 27 5 o ‘_'""':"RbF LiIE Arso°C, 9.0 0.0223463/T ) SRR (57-43) - - At 650°C, 3.4 - ' ’ ‘ o 3 & LiF-NeF-ZeF SUF, ALS00°C, 20.0 | e (35:32-29-4) At 800°C, 4.6 d NaF-LiF-BeF, At 575°C, 8.2 0.0784 ¢3944/T @ (64-5-31) At 850°C, 2.65 e KBeF, At 570°C, 20.0 0.00443 <7096/T (e) o " At 800°C, 3.3 | / NaBeF, At 600°C, 15.0 0.0411 &5148/7 () At 800°C, 5.0 g ' LiF-BeF2 (50-50) b RbF-Z+F -UF, At 550°C, 9.5 0.113 3648/T n (48-48-4) At 850°C, 3.1 Previously unpublished data, Previously unpublished data. Composition shown here is the nominal composition. Because of the KF present in the RbF used 'ro.prepare the mixture, the actual composition is RbF-KF-LiF (45.6-11.4-43 mole %). S, I. Cohen and T. N. Jones, Measurement of the Viscosity of Composition 86, ORNL CF-55-7-33 (July 7, 1955). dS l. Cohen and T. N. Jones, Measurement of the Viscosity of Composition 88, ORNL CF-55-8-21 (Aug. 15, 1955) €S. l. Cohen and T. N. Jones, Measurement of the Viscosities of NaBeI:"3 and KBeF g and Some Observatzons on (LzF-BeF2 50-50 Mol %), ORNL CF-SS 8-22 (Aug. 15, 1955). ' 4 Prevrously unpubhshed data, Composition shown here is the nominal composmon. Because of the KF present in the RbF used, the actual composmon is RbF-KF-ZrF -UF (38 4-9,6-484 mole %). j 7 : _ PERIOD ENDING SEPTEMBER 10, 1955 ? 1 i, | TABLE 7,3_. ] CURRENT VISCOSITY STUDIES ON MIXTURES CONTAINING BeF, e . . ‘- . ) . . C ; n ; | - . ) _ Mixture ACOmposifion (mole %) VISCOSIZPT 700°C BEF&,::;TB ! Reference 4 NaF-LiF-BeF, 4.55 34.1 (@) (64-5-31) | o - e KBeF, ” 44.7 %) ;o NaBeF, ' 8.1 52.8 () g LiF-BeF, 64.5 ' (b) 5 (50-50) : : NoF-BeF, 3.7 32.6 () (89, 8-30 2) A O ""NaF-L.F-BeFZ' - 4.4 46,7 () . FEEE S - T (27-35-38) ' B NaF-LiF-BeF jUF, 4.9 | 38.6 () - {26.3-34.1-37.1-2.5) s, 1, Cohen and T. N. Jones, Measurement of the Viscosity of Composition 88, ORNL CF-55-8-21 (Aug. 15, 1955). S. |. Cohen and T. N. Jones, Measurement of the Viscosities of NaBer and KBeFq and Some Observations on (LzF—BeF2 50-30 Mol %), ORNL CF-55-8-22 (Aug. 15, 1955). “Personal communication from J. F. Eichelberger, Mound Laboratory, to W. R. Grimes, CF-55-5-3, May 2, 1955. Personal communication from J. F. Eichelberger, Mound Laberatory, Aug. 1, 1955. . ) 7 UNCLASSIFIED THERMAL C_ONDUCT!VITY . : Tl ORNL-LR-~DWG 8948 ] 20 _ W. D. Powers " ® Reactor Experimental Engineering Division B N The thermal conductivities of molten fluoride " mixtures NaF-ZrF -UF, (50-46-4 mole %) and NaF-KF-LiF (11.5-42.0-46.5 mole %) were measured o with an alternate type of thermal-conductivity device, namely, a constant-gap cell. The results ® were in agreement with values previously de- termined by the variable-gap apparatus, e The thermal "conductivity of RbF- ZrF -UF, 0d - o/ | (48-48-4 mole %) is currently being meusured Also, the thermal-conductivity apparatus which will be used to study solid lithium hydride has been completed. sty o i, S e o Rk i MM s W B O - VISCOSITY (cp) ® - O MIXTURES RECENTLY’ STUDIED , - 2 @ MIXTURES PREVIOUSLY REPORTED 5 ELECTRICAL CONDUCTIWTY ) (ANP QUAR PROG REP, JUNE 10, 1955, ORNL 1898, . 159) , N. D. Greene , ) ' Reactor Experimental Engmeering Division The construction of the experlmenfa] platinum conductivity cell has been completed, The 0 4 . s0' e 70 inclusion of the fourth electrode should permit éF, CONTENT OF MIXTURE (wt %) L re lsi'wn‘y measurements to be made mdependently f the effecfs of polarization at electrode surfaces. i Fig. 7.8. Viscosities at 700°C vs BeF, Content After testing and standardization of the cell, . of Fluoride Mixtures Containing BeF,. Composi- measurements will be made of several fluoride tions of the mixtures are given in Table 7.3. salt mixtures, 157 i v o “ANP PROJECT PROGRESS REPORT 8 RADI AT!ON DAMAGE D S Bl”lngton J. B, Trice Sohd S’ra're Division The results of metallographlc examlnahon of fhe\ 'fluoride-fuef |oop recem‘ly operated in the LITR horizontal beam’ hole are presented. Corrosion of the Inconel tubmg by the c1rcu|atmg-erl mixture was, found to ‘be lqw. The mlnlofure in-pile loop " wads operaied for a short time in a vertical hole of the LITR, but the experlmenf was terminated | because of difficulties caused by failure of the - -7",:'pump motor. Modlflcchons to be mcde in the loop | " are descri bed. N Spec1men “assemblies bemg prepared for stress- ;:-:.;'_f_,;'_corrosnon experlmen’rs m the LITR are described, -~ as well as bench tests of an apparatus for creep tesfs in fhe MTR Flux measurements in the MTR . -_f-_f_’are ‘feported, and the results of analyses of ir- " “radiated reactor-grode beryllium are gwen. LITR HORIZONTAL-BEAM-HOLE FLUORIDE-FUEL LOOP C. Ellis J. G. Morgan 0. Sisman C. D. Baumann W. E. Brundage M. T. Morgan R. M. Carroll A. S. Olson ' W. W. Parkinson . Solid State Division The previously described! loop in which fluoride fuel was circulated in a horizontal beam hole (HB-2) in the LITR was examined visually, metal- lographically, and chemically for effects of the irradiation. During operation of the loop the maxi- mum fuel temperatures were 1450 to 1500°F; the fuel Reynolds number was 4500 to 6200 or about 5000 for most of the operation; the power gener- ation in the fuel was about 2.8 kw; the power density was 0.4 kw/;m3; and the duration of oper- afion was 645 hr, with the reactor at full power (3 Mw) for 475 hr. From flux measurements in the empty beam hole, it was eshmm‘ed that the power generated in the loop should be con5|derab|y higher than the 2.8 kw obtained from heat balance measurements, and BE V,_fi__fherefore an oddlhonal experiment was carried out ’ro meosure the flux depresswn m ’rhe fuel B O Snsmcm et al ANP Quar. Prog. Rep. ]une 10, T 1955. ORNL 1896 P 163 e 'in a simu!rated loop nosepiece. An assembly that duplicated the irradiated portion of the loop was made up and was filled with a 2% Cd-98% Pb alloy, which had the same macroscopic absorption cross section as the fuel salt. This assembly was inserted in a water-cooled jacket in hole HB-2, The neutron activation of the cadmium- lead alloy was measured, and the relation between the activation and the neutron flux was established by calibrating the data for the alloy with cobalt- foil data. Because of uncertainty regarding the position of the fluoride fuel loop in the hole, it was not considered that this experiment gave a reliable measurement of the flux, however, the flux distribution found did agree ‘with that cal- culated from the heat balance data and that de. termined subsequently from the cobalt foils that monitored the fuel loop. After disassembly of the loop in the hot cells, a measurement of neutron flux was obtained from the activity of cobalt monitor foils which were at various points in a copper tube attached to the nose of the loop. Since these foils were of necessity outside the fuel tube, it was also neces- sary to measure the activity of the Inconel fuel tube. The neutron flux was calculated from the data by using the relation, measured by Bopp,? between the activity of the Inconel and the flux. The neutron flux data obtained from the activities of the cobalt foils and the Inconel are plotted as functions of distance along the loop in Fig. 8.1. The fission power calculated from the Inconel activation was 2.8 kw, and the maximum power density was 0.4 kw/em?3. The fission power generated in the fuel was also determined by measuring the activities of fission products in the samples taken for chemicadl analyses., The octivity of the fuel was obtained with a gamma-ray spectrometer, and the height of the zirconium-niobium peak was compared with that of a standard. The zirconium-niobium concen- tration corresponded to a fission power of 2.0 kw, The zirconium fission product and the cesium flssmn product were qlso chemlcolly separc’red C D. Bopp, Gamma Radzatzon Induced in Engzneermg 7 Materials, ORNL-1371 (April 16 1953) B e ) ay A NEUTRON FLUX (neutrons/om- sec) 2 3 cnd 2. 5 kw.'_ ORNL~LR~DWG 83834 e COBALT-FOIL ACTIVATION 4 INCONEL-TUBE ACTIVATION 2° 4 & 8 10 12 14 46 18 20 DISTANCE"FRO'M' EN'D"OF Loop (in.) : Flg. 8. 1 from two of fhe scmples, ‘and the flssmn rate wds eshmated frorn fhelr CIC‘I’IVIi‘IG'S. The cesmm samples produced’ estimates of 1.5 and 2.1 kw, which were considerably lower than the determina- tions by other methods. The power indicated by the C5137 content could be expe=c'red to be low, since it is known that the gaseous parent, Xel37, "esccpes from the fuel mixture. The two separated zirconium samples mdlca’red fission powers of Thermul-Neutron Flux 'Traverse Along h , LITR Horlzonful-Beam-Hole Fluorlde-FUel LOOp, ) . UF, (47 wt %), 62.5 mole % NaF, and 12.5 mole % _A"ZrF and the enrichment was about 93%. be seen that the preliminary flushing with NaF- |n comparlng the resulfs of the | | :“'cofed by the elecfrlcal measuremenfs and' by ‘the ' flux defermmchons, |f should be kept m mmd 7 swn reuchons. 7 E’xamznazzon ‘ of ‘Number 4695-1, ORNL CF-55-3-179 (March 28, 1955). """:“"‘4G M. Adamson and R. §. Crouse, Examination of PERIOD ENDING SEPTEMBER 10, 1955 the end of the loop was about 0.4 kw/cm?®. The tube sections cut for chemical sampling were taken from both the in-pile and out-of-pile parts of the loop to ensure representative sampling. Fuel samples were taken from the ends of the tube sections by drilling out solidified fuel with carbide-tipped bits. Clean samples were obtained by collecting only ‘the borings from a small bit after a large bit had been used to drill through the surfoce material. been circulated during operation of the loop were obtained in the same manner from the portion of the loop filling line that was outside the pump shield. The samples were’ analyzed for uranium, zwcomum, and the constituents of Inconel (nickel, chromium, and iron). The results of the chemical analyses are presented in Table 8.1. The nominadl composition of the original fuel was 25 mole % It can ZrF, for cleaning and testing diluted the uranium content of the operating charge of the loop. The analytical results show that the uranium concen- tration remained unchanged during the run, that the chromium content increased from corrosion of the Inconel tubing, and that the nickel content ‘probqbly ‘decreased during the course of the corro- These changes in the concentra- "vhon “of |ncone! components in the fuel and the corrosive attack dlscussed below are consistent "';wnih observatlons on umrradmted Ioops.3 4 The 3G M Adomson, R S Crouse, and P. G. Sml’th ‘Inconei-Fluoride 30-D Pump Loop Fluoride Pump Loops 4930-A and 4935-1, ORNL CF- 55-4-181 (April 26, 1955). Samples of fuel which had - : in-pile "Fuel from Fu of-pile * portion of loop *The deviation listed is the maximum variation from the meqh of any but obviously contaminated samples. . 159 w 'plcflng out of RU "ANP PROJECT PROGRESS REPORT 103 Nb95 loop was described prev1ously The tube sections cut from the loop for metal- ‘lographic examination were cleaned of fuel to facilitate pohshmg and etching, They were placed '_verhcc”y in an inert-atmosphere furnace and held at ‘a femperature above 750°C until the fuel had completely drained from the tubes. Control speci- ;_Vmens (pieces of as-received tubing cut from the “ends of fhe fubes used to fabricate the loop) were examined | for comparison with the samples from the loop. The methods of examination and the results have been reported by M. J. Feldman and hns <:o-workers.‘S In general, ’fhe chcnges in the Inconel s were those expected in specimens subjected to 'rhe heat treat- ment imposed by the operation of the loop. The corrosion averaged 0.5 mil of penetrcmon. The penétration and the points from which specimens were taken are indicated in Fig. 8.2. No deposits of mass-transferred mate_ri'qi were observed. Also shown in Fig. 8.2 are the locations from which the specimens shown in Figs. 8.3 through 8.8 were cut. Figure 8.3 presents a typical sample M. T. 'Rrobins‘on, S. A, Reynolds, and H. W, Wright, The Fate of Certain Fission Products in the ARE, ORNL CF-55-2-36 (Feb. 7, 1955). " SM. J. Feldman et al,, Metallographic Analyses of Fuel Loop II, ORNL. CF-55-6-22 (June 21, 1955). onto the walls of the from the short out-of-pile section of the loop, the only section unheated during actual irradiation. This section was in the outlet leg of The !oop, and it was maintained ot about the femperature of the rest of the loop by the molten salt. Samples from this section of the loop showed the minimum corrosion attack, the average penetrahon being less than 0.5 mil. A sample that is typical of the entire unirradiated part of the loop is shown in Fig. 8.4; the specimen was taken from the inlet " leg of the loop within the LITR shleld The corro- sion penetration averaged 0.5 mil, and the maximum penetration was 1 mil. The maximum corrosion in the loop was found in the unirradiated portion of 'rhe ou’rle'r leg, Fig. 8.5, where the average penetration was ] m|1 cnd the maximum was 2.5 mils. The control specimen taken from the unused end of the tubing in the outlet leg of the loop is shown in Fig. 8.6. Surface cracks on the inner surface of the tubing were observed to be common in the control specimens. The cracks were probably respon5|b|e for occa- sional voids extending to depths of 3 or 4 mils in the loop specimen. A specimen from the tip of the irradiated loop nosepiece, which was closest to the LITR lattice, is shown in Fig. 8.7, The corrosion was about the same as the average corrosion found elsewhere, without the occasional deep voids shown in Fig. 8.5, The thick-walled tubing for the irradiated section was taken from : S50-B8-1257 : . -QRNL-LR-DWG-8384 —-—-,%. I WELDED JOINT BE.TWEEN LENGTHS OF TUBING ' NUMBERS REPRESENT PENETRATION IN mils SPECIMEN 19 SPECIMEN 11 SPECIMEN 2— CONTROL 1B CUT FROM THIS END 0.5 av 1.0 av 0.5 av C.5av >0.5av 3.0 max 0.8 mox 0.8 max 0.5 max 0.8 max i A) 7N T Te— AL z_/ N — 1 S A 1 A L ri 0.5 av 0.5 av 0.5 av lflZ\ 0.5 av 1.0 maox 1.0 max 1.0 max 0.5av 1.0 max 1.0 max ) _ 7 SPECIMEN 8 o 0 2 4 6 s Flg. 8.2 Locahons and Average and Mux|mum Depfhs of Corrosmn Aflack of LITR Honzontal Beam-Hole S F!uorlde-Fu .IflLoop. 8 10 - . 14 ‘ DISTANCE FROM END OF LOOP (f) - ' ' " L4 # 2y » 4 PERIOD ENDING SEPTEMBER 10, 1955 a different lot than that used for the umrmdlcted However, fhe Iarger grain structure observed may sechons. Anofher specimen from the lrradlated have been due to hlgher femperqfures res_ulhng section, taken from a lower flux region in the * from better contact with the tubular heaters. outlet leg, Fig. 8.8, exhibited the same degree =~ No increases in corrosion attack because of ir- radlctlon and no other unusual effects were found of corrosion afiack as thm‘ shown in Flg 8.7. UNCLASSIFIED _RMG 1154 UNCLASSIFIED RMG 1112 Fig. 8.4, Sfiééimefi 8: Sécfi;n of Inconel ‘Tub-in'g. Taken ‘fr..Om Unirrudiofed Porfibn of Inlet Legofl.oop Within the LITR Shield. 161 .ANP PR OJECT PROGRESS REPORT ‘ : ! 3 4 N Fig. 8.5. Specimen 11: Section of Inconel Tubing Taken from Unirradiated Portion of Ouflef Leg of Loop Within fhe LITR Shield. 250X. Reduced 3.5%. ' } Flg. 8.6. Control Specimen: Section of Inconel Tubing Taken from Unused End of Tubmg Used for Out- * “let Leg of Loop from Which Specimen 11 (Fig. 8.5) Was Taken. 250 X. Reduced 3.5%. 162 .z " ¥ 3 N PERIOD ENDING SEPTEMBER 10, 1955 'UNCLASSIFIED E NR;MG 1125; ! i i Fig. 8.7. Specimen 17: Section of Inconel Tubing Taken from In-Pile End of L.oop Nosepiece. 250X. E Reduced 4.5%. UNCLASSIFIED RMG 1134 Fig. 8.8. Specimen 19: Secfion of Inconel Tubing Taken from Outlet Leg of Loop Nosepiece. 250X, Reduced 4.5%. | o 163 i A oo ol dihes 3 ANP PROJECT PROGRESS REPORT in the loop. The results of this exper:ment are thus in agreement with the findings in some of the capsule irradiations.”’ The exper(menfal work on thls loop has been comple'red and a topical reporf is belng prepared : MIVNIAT_U R{E lN PIL E LOOP _”G w Kenlholtz | o H E Robertson C. C. Webs’rer _ W. R. WI”IS Solld Sfcfe D:vusuon D E. Guss o Unlted Sfcn‘es Alr Force The mlmafure fluorlde-fuel loop, descrlbed pre- v:ously, was operafed in vertical position C-48 ~of the L!T‘R( Because of faulty behavior of the pump~ motor, the fuel flow velocity could not be maintained at @ steady value, and the test was incomplete as a corrosion study. [t was possible, however, to make a fairly thorough study of in- pile characteristics of the loop, which operated for a total of 30 hr at full power, with a fuel Reynolds number of 3200 to 5000, The operation throughout this period was complicated by inter- mittent pump motor trouble, and the experiment was terminated when the motor stopped completely. The instruments controlled the temperature satis- focforily to within £5°F ond did not allow ex- cessive excursions in temperature when the fuel velocity chqnged rapid[y Several scram situations occurred during the short run because of low pump speed, high activity in the off-gas stream, and a high temperature indication that resulted from a thermocouple failure. All these situations were adequctely hondled in ’rlme to prevent high-tempera- ture excursmns _ Threg c_omponents of the loop were faulty: the pu{fiip""""""mb‘fpf, the pressure transmitters on the venturi ’rube, and the header box in the off-gas system. No complete explanation for the erratic behdvior of the motor can be given, as yet, but it appecrs that ’rhe combination of high temperature ~and very dry helium atmosphere caused brush ’fcnlure. An mduchon motor with a canned rotor “will be used on the next loop. 7W E Brownm Solid State Semiann., Prog. Rep. : .'Aug. 30, 1954, OR [- 1762, p 39. 8w. R. Willis et al., ANP Quar. Prog. Rep. Man 10, 1955, ORNL-1864, p 147, 164 “The pressure tronsmtfiers were unre[:cble, but it does not appear that any changes which could be made in a reasonable time would be of much ‘help. Therefore they are to be removed from the system. Removal of the pressure cells will permit “-“more of the loop to be lowered into the reactor. - This will increase the total power generation and will place the pomt of maximum temperature near ' fhe maximum neutron flux. During the short irradiation of the first loop a - gasket was blown out of the off-gas header box located at the face of the reactor. This allowed some leakage of activity into the midriff area of the LITR. The header box is to be redesigned to withstand the fuli, avculcble, air pressure without leaking. Since the flowmeter was moperoble, another method of obtaining fuel velocities was devised. The method used was to find the pressure de- veloped at a given pump speed and to find the change in pressure vs flow for the loop. These values were measured byusing water as the pumped fluid in exact duplicates of the pump and the loop. Figure 8.9 shows a plot of pump speed vs Reynolds number of the fuel. in Fig. 8.10 experimental and calculated curves of temperature differential in the loop as a function S SSD-A-1253 ORNL-LR-DWG-8380 104 PUMP SPEED (rpm) 103 {0 REYNOLDS NUMBER 10 Fig. 8.9. Pump Speed vs Reynolds Number of the Fuel in the Miniature In-Pile Loop. . e T " e W “t - - TEMPERATURE DIFFERENCE (°F) _ of Reynolds number are compared. S ated in the loop,' | 7 due tq_uhe loop was greater than estimated or . if the spatial distribution of the flux was greatly: “: altered, a lower‘ffemperofure differenhcfl than thut»___ ' .gfi'f'_-calculcfecl would have resul ted. “This poss:blhty"fl“' will be mveshgated when the values of the flux, " measured by a monitor in the loop, are known. T $SD-A-1254 ORNL-LR-DWG-8381 CALCULATED CURVE EXPERIMENTAL CURVE REYNOLDS NUMBER Fig. 8.10. Comparison of Calculated and Ex- perimental Temperature Differentials vs Reynolds Number in the Miniature In-Pile Loop. mental temperature differentials shown in Fig. 8.10 - are about 40% below the calculated values. This s cons:dered to ‘be a’ sohsfcc'rol’)' Check, e the assumpflons made in performmg the deslgn"“" '_ qlcuiahons vtended fo predtcf tempera'rure differ. "an d The next loop will be inserted farther into the PERIOD ENDING SEPTEMBER 10, 1955 active lattice to obtain a higher flux and a higher temperature differential. CREEP AND STRESS-CORROSION TESTS J. C. Wilson N. E. Hinkle J. C. Zukas Solid State Division W. W. Davis The Reactor Experiment Review Committee ap- proved the insertion of the pressurized stress- corrosion apparatus in HB-3 of the LITR. The apparatus, which was described previously,? is shown in Fig. 8.11. A thin-walled tubular speci- men, surrounded by an annulus containing approxi- mately 2.5 g of enriched fuel, is internally stressed by helium gas through the pressure chamber while being maintained at a temperature of 1500°F. The heat generated by the fissioning fuel is conducted through fins to a water cooling coil. A resistance The .ékpéri-' , thus, if the flux depressaon'”x'k 9W. E. Davis et al,, ANP Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 170. UNCLASSIFIED PHROTG 14344 PRESSURE CHAMBER PRESSURE TUBE L o Ll { for fuel annulus )} 1 SPECIMEN TUBE - FUEL TUBE COPPER SLEEVE (solders to water cooling coil } COOLING FINS e - i FueL TuBE PLUG Fig. 8.11, Stress-Corrosion Apparatus for Use in the LITR. ' 165 T N T P " T e o r ANP PROJECT PROGRESS REPORT heater spaced between the fins is provided for additional control of the specimen temperature. The control thermocouple on the inside of the specimen tube should give very nearly the maxi- mum temperature of the system at any time. Heat transfer calculations predict that the fuel will freeze at the outer walls of the fuel chamber so that the fuel will be contained in a cup of solid fuel; thus the surface-to-volume ratio of the test system will be considerably lowered. |t does not appear likely, at this time, that the tempera- ture of the specimen can be maintained at the control level during reactor shutdown perlods, however, fuels with a power density of 1000 w/cm?® are dlfficuh‘ to simulate in bench tests of this type of expenmenf. The gas space above the fuel is connected through a capillary tube to an expansion chamber to decrease the back pressure on the specimen walls when the specimen is brought up to temperature. The first group of specimen assemblies is now being filled with fuel for tests in the LITR. Engineering of the plug design to adapt the apparatus for insertion in the MTR is under way. A simplified version of the apparatus to permit creep data to be obtained in any combination of two nonfuel atmospheres is undergoing bench tests prior to irradiation. Measurements of the total strain in the specimen tubes will be ac- complished with a pneumatic measuring gage. Inside-diameter measurements of the specimen tube can be made with an accuracy of about 0.00005 in. with the pneumatic gage, and the manipulative operations are simple enough to be done in a hot cell. The operahon of a number of pressure-reducing valves, with pressure ranges from 200 to 1000 psi, has been checked over a period of about a week. Of the two valves presently being tested, one appears to be capuble of holdmg set pressures to within 1% over the range of room temperatures ‘encountered in the Iaboratory A 1:1 rcmo pressure-volume transformer for iso- lahng the gas inside the spec:men tube from the pressure supply has been built and tested. Be cause of the controlled limited volume of gas avmlable to the specimen tube with this apparatus, leukage or rup?ure results in only a very small pressure rise in the whole apparatus. Protection against pressure rises in the water-cooled irradi- 166 ation &R Will make possible a large reduction in the weight of the irradiation can. The MTR (tensile) creep test apparatus was irradiated for two cycles in hole HB-3 of the MTR at 1500°F and 1500 psi. For some unknown reason, two of the four Bourdon tube extensometers did not operate after insertion in the reactor. There- fore total creep measurements and a determination of the effects of radiation on the calibration fac- tors of the Bourdon tube extensometers will be made when the apparatus is returned to Oak Ridge. The apparatus has been cut from the irradiation plug at the MTR site. The bench test equivalent of the inspile rig in time, temperature, and siress has been assembled and testing has started. FLUX MEASUREMENTS IN THE MTR J. B, Trice H. V. Klaus Solid State Division F. J. Muckenthaler Applied Nuclear Physics Division T.L. Trent Engineering and Mechanical Division P. M. Uthe, United States Air Force J. F. Krause, Pratt & Whitney Aircraft R. H. Lewis, Phillips Petroleum Company F. W. Smith Consolidated Vultee Aircraft Corporation Neutron flux measurements have been in prog- ress for some time in hole HB.3 of the MTR.10 A - schematic diagram of the location of the HB-3 beam hole in relation to the lattice is shown in Fig, 8.12. High-energy flux data were obtained because of a need to know the fast-neutron flux intensity and distribution available for tests of structural properties of ART materials, For such tests to be realistic, both a high-energy flux and a high, integrated fast-neutron dosage were required. Thermal-neutron flux data were also obtained for estimating power generation in uranium-bearing fluoride fuel loops. The results obtained include a crude spectral analysis of the neutron energies in HB-3, made 105, B, Trice and P. M. Uthe, Solid State Semiann. Prog. Rep, Aug, 31, 1953, VORNL-160_6, p 23. e D) S sk ki . N w HB-3 beam hole. ‘:"??‘”fure bcsed on the UNCLASSIFIED ORNL-LR~DWG 8B36A B SHIM RODS 3 6 o Y re 12 ~INCHES Fig. 8.12, ‘Sch'érr;‘ufic-Difig.rum c;f MTR Lattice Showing Position of HB«3 Beam Hole, with threshold detectors and resonance detecs tors,'! thermal-neutron unperturbed flux traverses, and traverses made with mockup materials which simulated, more or less, the true neutron-absorbing - characteristics of in-pile fuel loops, 7 ngh-energy flux d:sfnbuflons are shown m Flg. 8,13, in integral form, for three positions in the The experimental points shown _ ‘Iear__reqchons listed in_ 'chle'fi 8 2 The‘dofled lines are fissu_on spectrvdk ndrmal-m fi'i___\ufrons decreases with mc‘reasmg\ dfstance oway“:”_ cafes 'rh“t the hlghesf - ”For method, see S VM. Dancoff et al., Activation Cross Sections by Boron Absorption, CP-3781 (May 6, 1947), p 17. PERIOD ENDING SEPTEMBER 10, 1955 UNCL ASSIFIED ORNL-LR-DWG 8644A — —FISSION SPECTRUM ® £ ' SPECTRUM TO 2.4 Mev O Rf11 POSITION, 2.8in. FROM BEAM HOLE END 4 R1{4 POSITION, 8.8 in. FROM BEAM HOLE END D R32 POSITION, 20.8in. FROM BEAM HOLE END ~ HIGH- ENERGY NEUTRON FLUX ABOVE THRESHOLD (neutrons /cm?2- sec) 0 2 4 6 8 O THRESHOLD ENERGY (Mev) Flg. 8 '|3 ngh-Energy Neufron ‘Flux Distribu- ‘tions in Three Posnhons in Hole HB-3 of the MTR. “of the nurnber of neufrons in the specirum above 0.1 Mev, based on measurements of the number of "“neutrons in the spectrum ‘above 2.4 Mev, as meas- ““ured with the reaction P31(z, p)Sn“ The ratio of the total number of fast neutrons in the spectrum to the fhermal-neutron flux, as shown in Flg. 8.14 ':':'":m‘ ‘the same posmon, is 0.135. At position HB-2 he in the LITR, the rcmo]2 is 0.80. This means ‘that 67 days ‘at a flux of 3,175 103 fast neu- 'trons/cm 'sec are required for the estimated total 12y B. Trice et al,, Solid State Quar. Prog., Rep. Aug, 10, 1952, ORNL-1359, p 12, 167 * ANP PROJECT PROGRESS REPORT fast neutron exposure of 1.8 x 102° 1o be reached, ~which is the estimated dosage for certain struc- tural members in the ART for an operating period UNCLASSIFIED ORNL-LR-DWG 8825A FLUX MEASURED WITH BARE COBALT -sec)” o " THERMAL-NEUTRON FLUX {neutrons/cm? 10 3 7 M 45 9 23 27 31 35 DISTANGE FROM BEAM-HOLE END (in) Fig. 8.14. Thermal-Neutron Fiux in Hole HB-3 of the MTR. of 500 hr.13 Since the flux g"radiént is very steep, as shown in Fig. 8.15, such a test would have to be made in a limited regioh in the beam hole. The " magnitude of the maximum instantaneous fasteneu- tron flux available, 3.1 x 1013, is less than the flux expected in the ART, 4 x 10'4, by about a factor of 10 and misses some aircraft reactor de- sign fluxes, for example, ~2 x 10'5, by about a factor of 70. Further analyses are being made in order to substantiate or refute these fast-neutron flux measurements, A series of measurements of flux depression in a mockup of a fluoride~fuel in-pile loop section as a function of amount of fuel present, wall thickness of the container, and position of the container were made in order to serve as a basis for design of a loop for operation in HB-3 of the MTR. The values of effective thermal-neutron flux obtained from this experiment were used to calculate the total power generation and power density to be expected in the loop. The apparatus for the series of measurements consisted of two major pieces. The outer piece was an Inconel cylinder 7 in. in length and hol- lowed to contain a solid-cylinder core of the neu- tron absorber used to simulate the fuel. The core 13y, K. Ergen, private -communication, Aug. 19, 1955. TABLE 8.2, CHARACTERISTICS OF DETECTORS USED FOR FLUX MEASUREMENTS | IN HOLE HB-3 OF THE MTR Threshold or Cross Section of Reaction Resonance Energy Resonance Integral Half Life Co%%(n,y)Cot? 120 ev 34b 5.2 years Na23(n,y)Na24 1710 ev 0.27 b* 149w C137(n,3)C138 1800 ev 0.348 b* 38 min V5 n,) V52 3000 ev 2.0 b* 374min AI27(n,)A128 9100 ev 0.14 bxrxx C23min P31 (n,p)si3" 2.4 Mev 75.0 mb*+ 26hr A2 (5, p M2 4.6 Mev 39,5 mb** 98 min 28(n pIAIZ8 5.5 Mev 79.8 mb** 2.3 min ' Ma24(n,0)Na?4 6.3 Mev 47.6 mb** 149 b A127 ()N o24 8.1 Mev 111 mb#* 149 he - '*S ‘M ‘Dancoff et al., Activation Cross Sections by Boron A bsorption, CP-3781 (May 6, 1947). **R. F. Taschek Radzoactwe Tbresbold Detectors for Neutrons, LADC-135 (also, MDDC-360, 17 1946) 1 68 | Declassified Sept. "% L .w v?‘\‘ : ", - UNCLASSIFIEb ORNL-~LR—DWG 8645A POSITION IN PNEUMATIC RABBIT 112 13 14 21 22 23 24 31 32 33 34 41 42 43 44 2 101‘! 5 2 RUN NUMBER DIA 10'° D1B DiC DiD SPECIAL RUN o 0 a n o o 4 6 8 10 12 14 16 18 DISTANCE FROM BEAM-HOLE END (in) HIGH-ENERGY NEUTRON FLUX ABOVE EFFECTIVE THRESHOLD (neutrons/cm®-sec) o ~ Fig. 8.‘157.7‘ _rFusf.-Né't-mon'Fl'uxr""l'ruverse of Hole HB-3 as Measured with the Threshold Reaction A127(n,c)Na?4 (8.1 Mev and Above). was assembled from two half cylinders slotted at intervals along the leng?h in such a way as to 'allow cobult f0||5 to be posmoned along the axis 7 ate conti _iwuth ?he two ‘halves of the ""cylmdér. Three ‘dlffefen’r core composmons “were o - namely, chmlum, boron, qnd”z in inti “Used. in k’rhe “Tithiom, »s_ts‘ Measuremenfs made with each of the three cores gave the same effective neutron flux within ex- perimental error limits. Flux traverses through the The cadmlum was\qlfoyed ‘with ‘mcgneslum.-;ondr S f_OM Yein. rods; the boron wds mixed, as'-, _ B C wn‘H a!ummum _by a pressmg and hIgh f..—,ngh- PERIOD ENDING SEPTEMBER 10, 1955 three cores with the reactor operating at 5 Mw are shown in Fig. 8.16. An operating power of 5 Mw, rather than the usual 30 Mw, was chosen because the gammaeray heat at 30 Mw would have raised the temperatures of the cores to above their melting points. The ther- mal-neutron flux as a function of power was ob- tained at two positions, as shown in Fig, 8.17, so that the flux-depression data obtained in the S 5 = = @ w & & = z 1z = ; @ & = = g ° < - o & 2 L 10 . . 0 02 04 06 08 1.0 £.2 1 O 04 02 03 04 05 06 07 08 09 10 41 42 13 ENERGY {Mev) * | ' ' ENERGY (Mev} ' ' " Fig. 8.18. Gamma-Ray Spectrum from Irradiated Fig. 8.19. Gamma-Ray Spectrum from Irradiated i Beryllium. Beryllium obtained from The Brush S & . Beryllium Co. UNCLASSIFIED 4 ORNL—LR—DWG 7923A 4X10 “05 06 07 08 09 10 11 i2 ENERGY (Mevy T o - be - 7- - i e Fig. 8..20. Garfima-.Rdy Spectrum from lrradiated | Beryllium, Beryllium obtained from R. D. MacKay Company. 171 T R T Gt s ANP PROJECT PROGRESS REPORT 9 ANALYT!CAL CHEMISTRY OF REACTOR MATERIALS C D Susano J. C. White Analyhcal Chem:éh‘y Division The n- butyl bromlde mefhod for the determmchon of ‘oxygen in sod;um was modified to ensure the ~elimination of possuble sources of contamination 7 _""‘3dur|ng analysis. The vacuum-distillation method oo for this de'rermmahon was investigated. Work was ‘ompleted on the volumetric determination of zir- - conium in fluoride ‘salts. A modlftcchon of the 4 "“'rappara’rus for’ the ‘determination of uranium metal '.;v'_;:n fluorlde sahs was mcorporcn‘ed to permn‘ a more V;l’dpld anclys:s Analyhcal assistance was ren- . .f_'-"r.‘i:;dered in the s'rudy ‘of using argon to eliminate air _i;,_from a dry box. !nvestlgahon of the application . Clof the brommatlon ‘method for the determination of fjif__:oxygen in zirconium fluoride and its mixtures with ‘>-~ofher fluorlde solts was continued. DETERMlNATION OF OXYGEN IN SODIUM ‘A. S. Meyer, Jr. W. J. Ross G. Goldberg Analytical Chemistry Division n-Butyl Bromide Method The n-butyl bromide method' is the standard method used in the ANP Analytical Chemistry Laboratory for determining oxygen in sodium. The original method has, however, been modified re- cently by two laboratories.2® In the modified procedures the organic reagents, n-butyl bromide and hexane, are purified and dried by passing them through a column packed with silica gel and dia- tomaceous earth. The purified reagents are stored over P,O.. A modification of the reaction tube has also been recommended to reduce atmospheric contamination. The modified method is reported to be very sensitive and to be applicable to the defermmohon of oxygen in sodium in concen- trations as low as 5 to 10 ppm. An evaluation of - these modifications was therefore undertaken pre- paratory to incorporating them in the standard procedure, ‘The reagents, hexane and n-butyl bromide, were purified and dried by passing the liquids through L '/_:'l'Cohf 1, c. White, W. J. Ross, and R. Rowan, Jr., Anal. V_K_‘Cbem. 26, 210 (1954). 2thyl Corporation, Baton Rouge, La. L.. Silverman, North American Aviation, Los Angeles, columns packed with silica gel and dlq’romaceous earth; they retained about 10 ppm water. They were then rendered anhydrous by desiccation with activated Al,O, or ons' The latter has the dis- advantage that it reacts with the water in the reagents to form acids which remain in the liquid phase in sufficient concentration to cause low results in the oxygen determination. Such an error can become significant when the reagents are stored over P, O, for extended periods. Also, anhydrous reagents become contaminated with water when exposed to the atmosphere. Wet re- agents lead to high results in the oxygen determi- nation. The n-butyl bromide procedure was further modi- | fied so that an atmosphere of argon was maintained over the reagents and reaction mixtures at all times. In addition, transfer of the reagents from the storage vessel to the reactor tube was carried out by applying pressure with dry argon. The modifications are illustrated in Fig. 9.1. Excel- lent reproducibility was obtained in the determi- nation of oxygen in sodium with the modified apparatus when the samples were taken in glass tubes. The oxygen content of the majority of the samples received from ANP facilities was in excess of 200 ppm. Much lower concentrations, of the order of 20 to 40 ppm of oxygen, were found UNCLASSIFIED ORNL-LR-DWG 8949 SERUM BOTTLE A RGON N2> % JOINTS TO 7-BUTYL BROMIDE VACUUM + HEXANE AGITATOR ALUMINUM OXIDE Fig. 9.1. Apparatus for Transferring Reagents in the Determination of Oxygen in Sodium by the n-Butyl Bromide Method. - . [ "' “of the scmple cup i in sodium samples which were subjected to la- borious purification. The n-butyl bromide method was also used to - study the effect of precleaning glass sample tubes prior to sampling. The interior of such sample tubes was found to be effectively cleaned of ' oxygen com‘alnmg lmpurmes by treating with - H,GO, or by flushing with molten sodium. A . multibulb tube is required to accomplish the . cleaning action with sodium. - Vocuum-Dlshlluhon Method A method is being ‘tested for the determmctlon ' of_ oxygen in sodium by titration of the Na,O that ‘remains after vacuum distillation of the sodium .. metal. A distillation apparatus has been con- structed that is srmllor to one developed by the Argonne National Loborotory ~The vacuum- ~distillation method of analysis is particularly ‘suited to the sampling of sodium at operating temperatures of the order of 1200°F and obviates the necessity for precooling the sodium before sampling. A schematic diagram of the equipment is shown in Fig. 9.2. The sample of molten sodium is introduced into the evacuated apparatus through a heated transfer line, which is maintained at the operating tempera- ture of the system being tested. The metal flows directly into a calibrated, hemispherical sample ‘cup, which is fitted with a thin, nickel liner. A volume of sodium sufficient to flush the transfer ‘line and sample cup is first passed through the apparatus. The excess sodium, which pours over the edge of the somple cup, is discharged into _a glass reservoir in which the volume of the flush ~ ‘sodium can e_observed With the pressure “of the“" - system mmntolned at Tess than 10 g, ‘the somple ~is heated fo 950°F ‘and the me1oH|c sod|um 15%‘:“ . ‘__:"dlstllled to the cooled ‘walls of the apparo'rus " When the dlsflllu‘l‘lba is complefe ‘the nickel Imer‘"’ : emoved, and the residual - N020 is dissolved and then tlfrofed\wnth a dilute °" 9* dized acid ured When 4J R. Humphreys, personal communication, June 24, 1955. i'fl"\e sfoble BeF the prehmmory rons PERIOD ENDING SEPTEMBER 10, 1955 are completed, the apparatus will be attached directly to a forced-circulation high-temperature- differential sodium loop, and analyses will be ‘carried out during operation of the loop (see Sec. 2, “Experimental Reactor Engineering’’). VOLUMETRIC DETERMINATION OF ZIRCONIUM IN FLUORIDE SALTS WITH DISODIUM DIHYDROGEN ETHYLENE- DIAMINETETRAACETATE (EDTA) A. S, Meyer, Jr. D. L. Manning Analytical Chemistry Division A volumetric method for the determination of zirconium in mixtures of fluoride salts was de- veloped. This method, which was outlined in the previous repon‘,5 was based on the work of Fritz and Johnson. ® The procedure consists in adding an excess of EDTA to a sulfate solution containing zirconium and titrating the excess with trivalent iron to a Tiron (disodium-1,2-dihydroxybenzene-3,5-disul- fonate) end point at a pH of 4.8. The color change at the end point is from yellow to purple. The- method is applicable to the determination of zir- conium in the presence of sulfate, tartrate, smatl amounts of fluoride, and hexavalent uranium. The yellow color of hexavalent uranium seriously interferes with the bismuth-thiourea end point proposed by Fritz and Johnson.® There are relatively few cationic interferences, because zirconium and iron form extremely stable complexes with EDTA. In the back-titration with trivalent iron the purple color of the iron-Tiron complex is not obtained until the metal-EDTA complexes, which are less stable than the iron - (IIH=EDTA complexes have been dissociated, .....Fluoride ion concentrations of up to about 0.1 M . do not appear to interfere with the titrimetric pro- .- cedure, Higher concentrations of fluoride ion can be effectively reduced by adding beryllium to the solution prior to the addition of the EDTA, The interference is removed through the formation of - complex " With a slight modification in the experimental o 'rocedure, the method is opphcoble to the determi- nohon of znrcomum m the presence of moderofe . SA 5 Meyer, Jr, cmd D L Monmng, ANP Quar Prog ‘Rep. June 10, 1955, ORNL-1896, p 177. 6J S. Fritz and M, Johnson, Volumetric Determination of Zirconium, an EDTA Method Regquiring a Back- Titration with Bismuth, 1SC-571 (Feb. 1, 1955). 173 P ANP PROJECT PROGRESS REPORT . vacuum —— -‘——————— 1000 °F\ C " TUNCLASSIFIED ~..ORNL-LR-DWG 8950 /CALROD HEATER 12006F\ N Z SODIUM Z& TRAP GLASS - METAL VACUUM FITTING CALROD TEFLON GASKET RN Y GLASS OVERFLOW RESERVOIR—7 | 7\ NS L HEATER =25 SODIUM VALVE :‘:5:=:1:'-\:-:-:-:-:;:;;ié nnnnann i j-e———— CALROD -HEA'TER 4 SAMPLE CUP WITH NICKEL LINER 4 A N f 1 D/A|R~COOLED CoIL L»// O | —s—— O -RING FLANGE GLASS PIPE FLANGE INSERT HEATER {000 °F \THERMOCOUPLE Fig. 9.2. Sodium Distillation Appqratus; amounts of trivalent iron, divalent nickel, and trivalent chromium. These metals form stable complexes with EDTA, ond therefore they would ordinarily interfere seriously with the zirconium determination. The interference can be overcome by forming the EDTA complex of the zirconium ““and the interfering metals. Fluoride ion is then SV added to the solution to selectively dissociate the zirconium-EDTA complex and form the stable ZrF,~" ion, thus liberating the EDTA. The liberated EDTA, which is a measure of the zir- conium, is titrated with the trivalent iron solution to a Tiron end point. The stability of the iron_ (I)~EDTA complex and that of the iron-Tiron R R T " ] oy o complex are not adversely affected by fluoride 7 ion. By utilizing Mthis'technicjue,' the procedure ¥ ~° can be made Specn‘lc for zirconium in the presence " of any metal ion that forms a complex with EDTA and does not dlssoc:cfe after fluorlde lon is added + fo the solutlon._ ) - The proposed volumetrlc mefhod has been tested - in fhe Iaborcfory and found to be’ suhsfcctory The - procedure resulfs in a considerable saving of time ~in comparison with ’rhe rather lengthy grav:metrlc | mandelic acid method. |t also appears to be more ecsnly adap’rable to the routine defermmqhon of zirconium ’fhan htrlmetrlc methods 1n whlch the‘ end point is detected spectrophotomemcally or cmperome?rlcaliy The coefflc:enr of variation is L ”of the order of 1% undep_' ldeal c«:ndmcns in ’rhe R range 15 to 45 mg of Z|rco'n'um ‘ DETERMINATION OF U ANIUMEMETAL- IN FLUORIDE SALT MlXTURES A 5 Meyer Jr B. L McDoweH - Anolyhcul Chemistry anls:on , The apparatus for ‘the determmuflon ‘of uranium ) me’ra! in mixtures of fluorlde salts by decompo- © sition of the hydride in an otmosphere of oxygen “at reduced pressures7 was modified by replacing copper oxide tube. The furnace used to heat the . sample was replaced wn‘h a micro- preheater for . each combustion tube. The heaters can be re- ’;;'j"moved from ‘the wcmlty “of the sample boct to allow more rap:d coohng of fhe hydride. ' modnf;ca’tlon A‘nalytlccl Chemlsfry ;DIVISIOI‘I - A sfudy of the rate of elimination of u’rmospher:c " gases from a dry box hcs been carrled out in These | PERIOD ENDING SEPTEMBER 10, 1955 conjunction with the Heat Transfer and Physical Properties Section of the Reactor Experimental Engineering Division, The concentration of oxygen in the atmosphere of a 21-ft° rectangular dry box was measured as a function of time while argon was being passed through the box at a constant flow rate. Oxygen concentrations in excess of 1% were measured volumetrically by absorption of oxygen in pyrogallol. Lower concen- trations were determined by a modification of the Winkler technique in which a suspension of Mn(OH) in an alkaline solution of Kl is equi- IIb!‘leECl with a measured volume of gas. The iodine, whlch is equwaienf to the oxygen in the sample, is liberated upon acidification of the solution and is determined colorimetrically or by titration th N025203 o ~When the gases in the dry box are thoroughly agitated by means of a blower, the oxygen concen- tration decreases exponenhcily with the volume of sweep gos in accordance with theoretical prediction. The oxygen can be eliminated more rapidly by introducing the more dense argon at the bottom of a quiescent dry box. Helium, when introduced at the top of the box, provides a some- what less effechve flushmg action thcn does . the smgle combustion ’rube with two combushon o °r9°" 'fubes, either of whlch can be connected to 'rhell The most effluenf flushmg was effecfed by injecting argon at the botfom of the dry box without supplementary agitation. With the highest argon flow rate available, 25 cfh, the concentration of oxygen “in the atmosphere of the dry box was reduced by a factor of 100 by flushing with two More fhon flve volumes of volumes of orgon. " re ’"'Simllar re- Prog. Rep ]une IO 1955, ORNL- ]896 p 174 M. Codell and G. Norwitz, Anal. Chem. 27, (1955). 1083 175 BT Lo sbo sl o Bl . v S "ANP PROJECT PROGRESS REPORT - This 'mefhod mvolves the reaction of a metal w ‘oxide with bromme vapor, in the presence of _"_'_’_f‘igraph:te, to form the metal bromide and CO. The ~CO is then oxidized to CO, by reaction with hot f Cu0. The amount of CO evolved is a measure o of fhe oxygen ortgmol[y present in the sample, ,_fThe opparatus for this analysis was described e prev:ously The prlmary objective of recent work has been S fo find the ophmum conditions for the determi- e nahon of oxygen in ZrF,. The oxygen in this S A';Z':}salt is present as ZrO or ZrOF2 or, possibly, el bo’rh compounds S An ofiempi was made to analyze synthetic _---'f-mlxtures of Zr02 and ZrF by the bromination ‘method. The recovery of oxygen as CO,, was f:ffmcomplete in all cases. Analyses of samples of _‘-'r-_»pure Z:0, by the bromination method also resulted ©in lncomplete recovery of the theorehcal amount T 'f-j{;of oxygen. .7 Several experimental conditions were varied in | lfi',,,"':_:these mveshgotlons The length of the platinum . “.beats was changed from ] to 3 in., and in some - experiments the sample wcs contomed on a sheet - of platinum. The weight of ZrO, was varied from 3 to 50 mg, and the ratio of ZrO, to graphite was < varied from 1:2 to 1:20. In one experiment, sugar -'_‘.:_"'-fcharcoal was substituted for the graphite. In these studles with ZrO2 ’ tcuned und the res;duol Zr02, which remalned in "Z,',the reacflon boat, were determined. The reaction involved in fhe initial step of the analysis is ZrO + 28!2 + 2C-——>ZrBr + 2CO :L';Therefore any ZrO which did not react with fhe- bromine should be found in the boat. The amounts of CO, obtained from these samples appeared to _'ceed the amount of oxygen actually removed from fhe ZrO This has been attributed, in part, o the presence of moisture in the graphite. -‘.lz,f‘Furthermore ‘the residual ZrO, found in the boat "varied | from 50 to 90% of the original sample ("‘:ffwelght for’ perlods of bromination of up to 6 hr at 950°C. - Since unsohsfactory results were obtained with sdmples of ZrO the method and apparatus were ,;,_checked wnh samples of TiO,. Only the amount 9J C. Wh:fe, J. P. Young, and G. Goldberg, ANP Quar Prog Rep Mar 10, 1955, ORNL-1864, p 161. S 10J P. Young and G, Goldber% ANP Quar, Prog. " ‘Rep ]une 10, 1955. VORNL']396: p 178. both the CO ob- | of TiO, remaining in the plafindm-(beefz'c'ffer;d:': o | 2-hr penod of bromination was determined in these studies. Cqmplete removal of the T|02, as the bromide, from the boat was achieved when the oxide and graphite, approximately 15 mg each, were mixed together with a mortar and pestle. When the two materials were mixed by using a spatula, quantative removal of TiO, from the boat was not obtained; however, when fhe mixing was done with great care, up to 95% of a 10-mg sample of TiO, could be removed as TiBr4' in 2 hr, The sample preparation described by Codell and Norwitz® consists in placing titanium chips, metal or alloy, between two layers of graphite. In this case, it is probable that the volatilization of the metal as a bromide would leave the re- maining TiO, in intimate contact with the graphite, without the need of external mixing. It would also be probable that, in the determination of the oxide contamination of salts that are volatile at moderate temperature, there would be no need for tedious sample preparation. For a determination of oxygen in a material containing greater than 1% oxide, it would be advisable to ensure an intimate mixture of the sample and graphite. The information gained in the study of the bromination of TiO, will be applied to the determination of oxygen in Zr0, and other oxides of interest. The formation of a precipitate on the surface of the BG(OH)2 bubbler, which was reported pre- vnously, was prevented by inserting a thin platinum tube inside the ignition tube. It was necessary to use this platinum tube only during the analysis of samples containing fluorides. |t "is believed that the contact of volatile fluoride salts with the hot quartz of the ignition tube re- sulted in the formation of SiF,. This gas reacted with the solution of Ba(OH), to precipitate BaSiF . The platinum liner inserted in the ignition tube prevented the formation of SiF . Dei'ermi natieh ef CO by Means of a Solution of PdCI, Various methods for determining CO are being investigated. The purpose of these studies is to find a sensitive method for a more direct measure of the CO that is formed in the determination of oxygen in metal oxides by bromination. A method for the determination of CO in blood w T R R AT T0 R T Y i W oay, is of current Im‘erest This method involves the followmg reachon PdCi +CO+H O—-> Pd+CO +2HCI Carbon monoxu:le is ollowed fo react W|'rh 0.01 megq of PdCl in 0.001 N HCI; the solution also con- tains MgCI to flocculate the colloidal palladium that is formed in the reaction. The net increase in hydrogen ion concentration, determined by hfrchng with a base and using an indicator of bromophenol blue, is a measure of the CO that was originally present. ‘In the present study, it was necessary to use a greater amount of PdCl, (1 meq) and to eliminate HCI in the preparahon of the reagent. Poiassium chloride proved to be an effective substitute for HCl in the dissoluhon of PdCI : Tifrchons of synthetic mixtures of HCl and - PdCI2 were performed to find suitable conditions for a determination of HCl in such solutions, Since solutions of PdCl, exhibit considerable buffering action at a pH of 4.5, it was not possible to determine HCl in a solution of PdCl,,. Several means of removing the palladium ion were investi- - gated, and the addition of Kl was found to be effective for this purpose. Excellent titration curves ‘were obtcuned when an amount of Ki, in excess of the amount of F’c{CI2 was added to the solution containing HCI and PdCl, prior to the: titration of HCI. The change in pH, during the ~ titration, was observed by means of a pH meter, ‘and plots of pH agcnnst ‘the quantity of base added were prepared from the data. These plots are shown in Fig. 9.3. Subsequent studies are planned to investigate the appllcoblhty ‘of this method to o 'the determination of CO in the off- -gases resultlng L — frpm fhe brommohon of metallic ox:des. __Reactor Chems"y 99 2838 AN_P SVERVICE LABORATORY o | O ' R W: l|ams; I o L~ 3.0 —— —oo? w 2.0 1.0 o 2 4 6 8 10 12 t4 16 18 20 NaOH ADDED (mi} Fig. 9.3. Effect of Kl on the Titration of PdCl, and HCI with NaOH. 22 - G. I. Cathers PILOT PLANT DESIGN o A project analysis will be completed soon that will serve as a basis for establishing an accurate . schedule for design and construction of the pilot plant for recovering fused-salt fuels, A new cost estimate will also be made. Certain delcys in design and procurement make a construction com- '3 -~ pletion date near the end of February 1956 more { " redlistic than the December 31, 1955, date previ- 1. ously planned. An engineering flowsheet was issued that is subject to revisions as needed to stay abreast of laboratory work. Approximately 65% of the proc- ess equipment items are on hand or are in some stage of procurement or fabrication. g . The dump tank containing the ARE fuel was & ~ moved uneventfully from Building 7503 to Cell 3, i | Building 3019, on July 27, 1955, It is no longer I planned to force the molten fuel out of the dump tank by nitrogen pressure, Instead, the dump tank will be inverted inside a fumace liner, and the fuel will drain out of the dump tank into the liner and thence to a heated pressure vessel, where it will be stored in the molten state until processed The moHen fuel will be forced from the pressure "'”’vessei or hold fonk mfo the fluormchon vessel by nn‘rogen pressure. - S A e e T Lt ¥y : o "sccmmng other equipment in the cell, E NGINE RING D VE LOPME NTS Dtrecf-resustcnce heofmg was tes'red becouse of its simplicity, as a means of preventing plugging in the transfer lines between the fluorinator and - tve uranium-bearmg salfé - A :closed-cn'cuat telews:on system wnll be ‘Used as an _‘cud in posmonmg “the cans and for ' PERIOD ENDING SEPTEMBER 10, 1955 ? 10. RECOVERY AND REPROCESSING OF REACTOR FUEL ; F. R. Bruce | ' D. E. Ferguson W, K. Eister H. E. Goeller [ M. R. Bennett J. T. Long | F. N. Browder R. P. Milford S. H. Stainker Chemical Technology Division the ARE dump tank or the waste-salt receiver. With I/A-in.-dia 0.035-in.~thick-wall Inconel trans. fer lines, a cutrent of 75 amp was sufficient to keep the salt molten, except at fittings, where supplemental extemal heating was necessary, It was recommended that such heating units be built into the piping in the Fluoride-Volatility Process Pilot Plant, A freeze valve (Fig. 10.1) was designed for closing the molten salt transfer lines leading to and from the fluorinator, since no reliable mechani- cal valve is available. The valve operates by the PHOTO 15053 _a— VENT AND NITROGEN INLET IDISENGAGING | SALT INLET DIAPHRAGM (BACK OF 'DOWNCOMER) Fig. 10.1. Freeze Yalve for Molten Salt. 179 Rt i s ANP PROJECT PROGRESS REPORT freezing of a plug of salt in a vented trap in the line. The salt outlet is barely visible behind the downcomer in the phofograph. Novel features of the design are the provision for inertgas blow- ‘back through the inlet pipe and the conical bottom to minimize holdup within the valve and to lessen the mechanical strain imposed by expansion of the salt during melting, After 15 cycles of freezing and thawing, this valve, when frozen, held against " a test pressure of 20 psig without [eaking. " The nature of gas dispersion through a percola- ~ tor type of gas-liquid contactor was studied, and the liquid recifculdfion rate was measured as a ' functlon of gas flow rate, gas inlet configuration, “and percolotor tube length, diameter, and sub- mergence, The data are being analyzed for use in ~designing a fluormcn‘or for the fluoride-volatility ' .process. o e -;;-,;j_‘ PROCESS DEVELOPMENT An Improved procedure for deconfcmlnufmg the UFé product of the fluorination step was de- veloped (Fig. 10.2). The procedure is based upon UF “absorption on NaF at 100°C and desorption by heating to 400°C, with the product gas passing NoF ABSORBENT BED (ABSORPTION OF Ug AT $00°C, DESORPTION AT 100 TO 400°C — through a second bed of NaF before collection of the UF . in a cold trap. The over-all gamma de- contammcn‘lon factors of greater than 10° that were obtained are to be compared with the decontamina- tion factors of only about 104 obtained with the process in which a single bed at 650°C! or at 100 to 400°C was used. In the single-bed proc- ess, cross contamination occurred because of the use of the same lines for collecting the product and for handling the waste gases containing small amounts of fission products, and, as a result, the decontamination factors are much lower in re-used equipment than in new equipment. Since fission products never enter the product-collection system in the two-bed process, decontamination factors of greater than 10° were obtained in re-used equip- ment, Preliminary results indicated that the use of nitrogen as a sweep gas in both the fluorination and the NaF absorption and desorption steps re- duced the amount of fluorine required for the process. o In the first decontamination studies, a single, 1F R. Bruce et al., ANP Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 181. ORNL—LR~DWG 8952 COLD TRAP FOR VOLATILE FISSION PRODUCTS / F, WASTE COLD TRAP FOR UFg PRODUCT UF; ABSORPTION STEP —_— F, ' UFg+ Ny +Fp Bd.f.~200 FLUORINATOR—» 600°C ol ARE FUEL {~ B mole % UF, IN NaF = ZrF,} \Q DY WASTE SALT © >99% FISSION PRODUCTS . <0.02% URANIUM an. 10 2 Fused Salt F|“°"de'v°|°*'|“y Process in Which Two NoF Absorbent Beds Are Usedr o e F, WASTE / Bd.f =10% T0 105 2 UF. DESORPTION STEP - e A\ /| NaF ABSORBENT BED { ABSORPTION OF FISSION PRODUCTS AT 100 TO 400°C) e e L2 P [ . | 18-in.-long bed of NaF was used. The UF, efflus ent from the fluorinator was passed through this bed at 100°C, and then the flow was cut off while the bed was heated to 400°C to desorb the UF . As shown by analyses of the contents of the cold trap after the absorption step and of the residual NaF after the desorption step, 50 to 90% of the volatile ruthenium passed through the NaF at 100°C, and more than 99% of the absorbed ruthe- nium was not desorbed on heating to 400°C, Es- sentially afl the niobium was absorbed at 100°C and was not desorbed at 400°C, which gives a decontamination factor of about 10% for the absorp- tion-desorption step. When new tubing and equip- ment were used, the over-all decontamination fac- tors for the single-bed process were about 104 (Table 10.1). | When the gas lines and equipment were re-used, ‘ruthenium that had been deposited in them in pre- vious runs prevented good product decontamina- tion, To avoid this contamination, two 9-in,-long beds were fried. The UF, was absorbed in the first NaF bed, the unabsorbed fission products PERIOD ENDING SEPTEMBER 10, 1955 being collected in a cold trap. The line to the cold trap was closed during the desomption step, and the product stream was passed through the second NaF bed for absorption of any fission prod- ucts desorbed from the first bed or from the walls of the lines between the first and second beds (Fig. 10.2). In two test runs, UF, product con- taining about the same beta and gamma activity as natural uranium, or less, was obtained, The gross beta ot gamma decontamination factors for the whole process were of the order of 105, Because of the low product activity, calculation of the various specific decontamination factors was not practical, The effectiveness of the method, how- ever, was shown by the distribution of activities in the two NaF beds and the cold trap used in the absorption step (Table 10,2), A yield of only 40% was obtained in the two runs because of poor temperature control of the 9-in.« fong beds. In two later runs, 6-in.-long beds with better insulation and heating control gave yields of 90 to 100% with the same high decontamination factors of about 105, The same NaF was used in TABLE 10.1, DECONTAMINATION OF UF, IN THE SINGLE-BED FUSED-SALT FLUORIDE-VOLATILITY PROCESS u F6 in F-N, gas stream from fluorination of NaF-ZrF ,-UF , (gross beta activity per milligram of U in salt =5 x 10° counts/min) at 600°C; absorbed at 100°C and desorbed with excess F2 by increasing the temperature from 100 to 400°C Absorbent: F2/U mole ratio: ~5 NaF /U weight ratio: ™6 200 ml of 12- to 40-mesh NaF in l-in.-dia bed < ..PdelfJ»f:fyiéid:" 870 " Decontamination Factors ' Radioactivity ~ Over-all, S Absorption™ Desorption™* Including Sl e o Fluorination . Gressbeta a2 40 - 12x 0t .7 Gross gamma a2 310 14 x 10 ‘Rugamma 24 46 '7 1100 ZeNbgamma 10 1600 | 5.9 x 104 *Based on activity not absorbed with UF6 on NaF but passed into cold trap. **Based on activity remaining on NaF after desorption of UF6' 181 TABLE 10. 2 DISTRIBUT!ON OF ACTIVITY IN THE TWO-B ED FUSED-SALT FLUOR!DE-VOLATlLlTY PROCESS UF6 in F2-N2 gas stream from fluorination of NoF-ZrF -U F4 (gross beta activity per m:”lgrom “ofUin salt =5x 10° counts/mm) at 600°C; absorbed on first bed ot 100°C, with some ochv:ty permtfiecl to pass into cold trap; desorbed with excess F by increasing the temperature from 'IOO to 400°C with gas passmg from first bed through Second bed to UF cold trap Absorbent beds 7 100 ml of '|2- to 40-mesh NaF in 1-:n -dlu fubes . Tota_l Na_F/U weight ratior ™~ 6 Percentage of Total Volatilized Activity ety o o S In Cold Trap _ InBed1 InBed2 InCold Trop InBed 1 In Bed2 Gross beta 51 48 0.8 59 7 Gross gamma 3 97 0.07 7 93 o002 Ru go.mmo o 81 | 18 0.9 86 1';1' | Very . Tow ZeNbgamma T o4 ~00 0.4 0.8 99 0 02 ' . 0.-1 . 2 97 i Very Iowki Co _'ll'ofc:i rare eofl'h beta 3 97 rithe second run"a‘s in the flrst ond 'rhus, for the first time, it was established that activity can be ~prevented from seriously contaminating the product - UF process lines. Since the NaF/U weight ratio in each run was 4, the over-all ratio after the second run was 2, The uranium loss in the cold trap used in the absorption operation at 100°C varied from less than 0.001 to 0.04% in the four runs with the two beds. Less than 0,1% of the total uranium proc. essed was found in the NaF in the two runs with the use of the same NaF beds. in the last two runs, an equal-volume mixture of fluorine and nitrogen was used for the fluorination until about 75% of the uranium had been volati- lized, pure fluorine being used to remove the last - of the uranium from the molten salt, The induction period observed previously? was eliminated, and uranium losses in the waste salt were only 0.013 and 0.004% with F,/U mole ratios of 3.7 and 5, respectively. The over-all F,/U mole ratios, in- cluding the fluorine used for desorbing UF, from the NaF, were 5.6 and 6.7, which are somewhat lower than the ratio of 9 used in previous! NaF decontamination studies. | Preliminary results also indicated that nitrogen can be used to replace part of the fluorine used in the NaF desorption step. A 10-g charge of 12- to 40-mesh NaF in a "/Z-in.-dia nickel tube at 100°C was saturated with about 9.5 g of UF, and then raised to 400°C for approximately 30 min to desorb the UF, while nitrogen was being passed through the tube at a rate of 200 ml/min. In two trials, approximately 80% of the UF, was removed, This method has not yet been used with activity present. 2p. E, Ferguson et al.,, ANP Quar. Pog Rep. Manr % 5 i s i . i 4. < * ® ~ * r ., t 4 Part |l SHIELDING RESEARCH o L » » 11 SHIELD DESIGN J. B, Dee - C. A, Goetz J. E. Smolen H. C. Woodsum Pratt & Whitney Aircraft A survey of spherically symmetric unit shields for circulating-fuel reactors was made, and weight estimates for unit shields with various dose rates at 50 ft are presented. The chief sources of radia- tion in a 300-Mw circulating-fuel reactor for the NJ-1 power plant were determined. A parametric weight study of the shield weight dependence on the dimensions of a 300-Mw circulating-fuel reactor is described, WEIGHTS OF SPHERICALLY SYMMETRIC UNIT SHIEL DS FOR CIRCULATING- FUEL REACTORS Y survey of spherically symmetric unit shields for circulating-fuel reactors was made for a range in dose rate of 0.1 to 10 rem/hr at a distance of 50 ft and a range in reactor power of 100 to 300 Mw, An estimate was obtained for the added weight of an NaK-to-NaK secondary heat exchanger and its shielding. This additional weight is quite sensi- tive to the manner in which the dose rate is divided between the secondary heat exchanger and the reactor and to the absolute value for the sodium activation. Consequently, the estimates must be interpreted as indicating trends rather than absolute values. The reactor dimensions for this survey were scaled from those glven previously ! for a 300-Mw reactor having a power density of 2.75 kw/cm ’ “and the secondary heat exchanger dimensions were scaled from a Pratt & W ittn‘ey Aircraft de5|gn. ’The shreld dlmensmns ‘were p‘snon and the data d shleld 3 ]ANI_’ Quar Prog. : "p 74 ; Rep Mar , L E. P. Blizard and H. Goldstein, OR 1954), - 3F H. Abernathy et al., Lid Tank Shielding Tests for the Reflector-Moderated Reactor, ORNL-1616 (Cct. 5, 1954). o determrned by the mefhods g‘lven by fhe ]953 Summé;r Shle'dlng Con efhods presén é‘dj in fhe o A:le Tan‘k Shleldmg“"Fqcllii‘y (LTSF) report on an’ s v S s On'\a Clrculatlng-erI s H0wever' "; 1953, ‘ORNL-ISIS - alkylbenzene in such a manner as to attenuate the neutrons as rapidly as the gamma rays and, thus, to ensure the effectiveness of the lead; this method is conservative. An analysis of data from the current L TSF circulating-fuel reflector-moderated- reactor and shield tests (see Sec. 12) should make possible a shield arrangement that would result in a saving of several thousand pounds of thick gammea-ray shielding for unit shields. Additional weight savings could be achieved by shield-shaping according to the particular aircraft application and . configuration. The source of data for the sodium activation for these calculations was the current LTSF tests, teported previously.? Results of this survey are given in Table 11.1 and Fig. 11.1, A ORNL-LR-DWG 61424 =% o o o 5 Lo .-‘:\ 2 E 2 = o w0y — L3 w 0.5 w o a 0.2 M0 o L OOO\ 180 [o X 400 150 200 250 300 REACTOR POWER(MW) Fig. 1L.1. Weights of Clrcu!ohng-Fuel Reactor “‘and Shield Assemblies Without NaK-to-NaK Heat Exchangers. - $OURCES OF RADIATION IN A 300-Mw ::j:f CSRCULATING-FUEL REACTOR _\:iThe chief sources of mdlahon for the 300-Mw 2Report of e 1953 e szeldm{S'esszon, ed by c:rculafmg-fuel reacfor fcr fhe NJ-T ‘power plant 1575 J 11, 73 Yene Ll 4G. T. Chapman, J. B. Dee, and H. C. Woodsum, ANP Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 194. SPratt & Whitney Aircraft, NJ-1 Powerplant Character- istics Summary, PWAC-126 (Mar. 16, 1955). 185 s ANP PROJECT PROGRESS REPORT TABLE 11.1. DIMENSIONS OF CIRCULATING-FUEL REACTORS AND CORRESPONDING REACTOR — UNIT SHIELD WEIGHTS FOR VARIOUS DOSE RATES AT 50 ft Reactor Power (Mw) 100 ' 200 300 7 Dose Rate at 50 ft (rem/hr) _ 0.1 1 10 0.1 1 10 0.1 1 16 All Components -Excepf Shielding and NaK-to-NaK Heat Exchanger Thicknesses (in.) Core 4.09 4.09 4.09 5.18 5.18 5.18 597 5.97 5.97 Beryllium reflector 12,60 1200 12,00 1200 12.00 12.00 12.00 12.00 1200 Fuelfi-fo’-NdK heat exchanger 2.81 2,81 281 4.57 4.57 4.57 572 5.72 5.72 Outside Radii (in.) ' ' Beryllium island 4,62 4.62 462 5.8 5.88 5.88 6.685 6.685 4.685 - Core’ o 9.04 9.04 9.04 11.38 11,38 11.38 1297 1297 1297 Beryllium reflector 21.37 21.37 21.37 23.70 2370 2370 25.31 2531 2531 Fuel-to-NaK heat exchanger 24.53 24,53 24,53 28.62 2862 28.62 31.38 31.38 31.38 Weights (103 Ib) ’ "-l-?e.ocfor“(b;‘essuw shell and con= tents including pump headers) 13.4 13.4 134 203 20.3 20.3 27.7 27.7 27.7 Insul ation 0.18 0.13 0.18 0.24 0.24 0.24 0.28 0.28 0.28 CANETYE Syrycture 2.90 2,54 2,18 3.15 2.82 2,50 3.25 3.00 270 ‘ Patches/ 2.81 2,57 2,40 47 4,16 3.77 6.66 5.83 5.25 NaK -fo‘-NVGJI‘( Hécr} ‘Exchanger Thickness (ft) 1,507 1.504 1.50% 2.12% 2.12% 2,128 2.60° 2.60° 2.60° Weight (10° Ib) 3.01 3,01 3.0 571 5.71 571 8.5 8.5 8.5 Lead Shielding of NaK-to-NaK Heat Exchanger ' Thickness (in.) 3.49 1.09 © 4,48 2.09 0 4.85 2.55 0.022 Weight (103 1b) 6.55 2,50 0 14.18 5.99 0 21.14 10,28 0.08 Lead and Alkylbenzene Shield Qutside diameter (ft) 11.65 10,64 9.32 12,58 11,23 992 12,99 11.62 10.31 Thicknesses Total lead {in.} 10.57 8.71 7.7 1117 9.20 7.52 11.45 9.43 7.85 Total alkylbenzene (ft) 2.884 2.362 1.821 2.788 2,278 1.762 2.739 2,223 1.699 Weights (10° [b) Total lead 70.99 49.39 36.13 93.55 66.33 48.85 109.55 78.85 59.78 Total atkylbenzene 33,27 25.06 15.91 40,92 28.12 18.08 4391 30.15 1936 Total Weight of Reactor and Lead- 123.55 93.14 70.20 162.87 122.02 93.74 191.35 14581 115.07 Alkylbenzene Shield Assembly (10% Ib) Total Weight of Reactor, Lead-Alkyl- 126.56 96.15 73.21 168.58 127.73 99.45 199.85 154.31 123.57 benzene Shield Assembly, and Non- ' shielded NaX-to-NaK Heat Exchanger (103 1b) Total Weight of Reactor, Lead-Alkyl- 123.65 benzene Shield Assembly, and Shielded _ NaK-to-Nak Heat Exchanger (]03 ib) 133.11 98.65 73.21 182.76 133.72 99.45 220.99 164.59 3 ft wide X 2.9 ft long NaK«to-NaK heat exchanger. b4.24 ft wide % 3.15 ft long NaK-to-NaK heat exchanger. €5.2 ft wide X 3.4 ft long NaK-to-NaK heat exchanger. Ry "~ 5 S i i et | e weime oonol o, * » have been determined. 7 The reactor dimensions used for this study are given in Table 11.2, and the sources of rcdia’rion are lisfed in Table ” 3. TABLE 1.2, PARAMETERS OF 300-Mw CIRCULATING-FUEL REACTOR USED IN CALCULATION OF SOURCES OF RADIATION Thickness Raaius Reactor Re‘g!ion' (in.) (in.) Beryllium island 6.690 Inconel-X cladding 0.01 6.700 Sodium passage 0.1875 6.888 Inconel-X core shell 0.125 7.013 Core fuel region 5,987 13.000 Inconel-X core shell 0.156 13.156 Sodium passage 0.1875 13.343 - Inconel-X cladding 0.01 137.‘353 ‘Beryllium reflector ' 11.908 25.261 fir?cone] X cladding -. 0.01 25.271 |8 10 ceramel 0.10 25.371 dnconel «X claddmg 0.01 25.381 Sodium passage - 0.1875 25.568 " Inconel- Xéclcddlng' 0.125 25.693 Heat exch}irnger 7.13 32.823 Inconel-X cladding 0,125 32.948 Inconel-X thermal shield 1.00 33.948 Pressure shell ~ 1,00 34,948 Insulation 0.25 % 35.198 Insulation cladding 0.032 ! 35.230 VAIkylbenz}ene passage 0.375 35.605 lead o 1.00 36.605 A.Ik'ylbenzene passage 36980 “byvan mdependent me’rhod in which the max1mum" number of captures in the core shell was found by “assuming thermal absorption in the core shells and * “CAPTURE'RATE (captures/cm®-sec) PERIOD ENDING SEPTEMBER 10, 1955 all thermal fissions in a blackzcore. For each k2 neutron captured in the core, ¢ * neutrons were assumed to have entered the Inconel. The total inconel capture rate was therefore the core capture rate multiplied by (e ® ~ 1), where ¢ is the Inconel shell thickness, %, is the neutron absorption cross section at the neutron temperature, and £ is a constant with a value between 1 and 2 that depends upon the anisotropy of the neutron flux., This % is in agreement with that obtained in recent foil measurements at the ORNL Critical Experiments Facility, and, also, with the multigroup results, which correspond with a value of & = 1.65. The neutron copture rates in the reactor are shown in Fig. 11.2, - The prompt-fission gamma-ray spectrum used is based on the data of R, L. Gamble (see Table 11.3), This spectrum is thought to be reasonably correct in total energy, although deviations by a factor of 2—-01-059-22A ISLAND C REFLECTOR O- ™ N o 4 N CORE SHELL CORE SHELL (OUTER) (INNER) T b 10” 0 0 20 30 40 50 60 70 RADIUS (cm) Fig. 11.2, Capture Rufes;};;l‘lv‘lle:utr'c‘b.hs in a 300-Mw Circulating-Fuel Reactor (Based on Foxcode Multigroup Calculations). 187 psillcoiili i c Rl s S Rl sl s bl s catiiad ot i ANP PROJECT PROGRESS REPORT i i G TABLE 11.3. SOURCES OF RADJATIONIN A 300-Mw CIRCULATING-FUEL REACTOR : - . o o | ) Photon i Photon Emission : Neutron Cra;:a;ur‘es'r " Neutrons . Region Photon Source ' Efiérgy(a) Probability per Second Produced ok o - T (Mev) per Copfure(a) at 300 Mw per Second 7 Asland ' n,y) in beryllivm 68 075 0075 10'® » o ~3.4 ' 0.50 Core shell (mnel') ('nf)/)- .ifiwrinrc;fi)el‘(b) = 9 0.72 0.28 x 1018 | | | : ~4 7004 - | ot Core Prompt-fission E 7.7 e~ 1-03E y4gle) 9.5 x 10'8 23.3x 1018 : ~ gamma rays ' : F'is:;;ioh-prodfiéf B (7.0 e~ 1-2E gp)ldie) S ‘gamma rays ' o o X | S ey in U238 E (8 e~ 1-03E gp)(/) 1.6 x 108 Core shell (outer) (ap)inlnconel 9 072 127 x10'8 B L T - 04 | | e Reflector ~ (n;y)inberylliom 6.8 0.75 138 x10'8 ey, S . ™34 0.50 - Heaf exrcil"-aanger | Fissidfi-produ.ct E (7.0 ™ 1.2E ypy(esg) Dl . gamma rays . ) L L ' : 12(P) Gamma shield (n,y) in lead 7.38 0.93 6.8 x 1013 . ~6 0.07 Hydrogenous shield V(n",}/) in borated(?) __ . : alkylbenzene ! () (n,y) in hydrogen 2.2 1.00 9.6 x 1013 (n,y) in boron 0.48 0.94 3.7 x 101° ap, Mittleman and R, L. Liedtke, **Gamma Rays from Thermal-Neutron Capture,’”’ Nucleonics 13(5), 5051 (1955). byalyes for nickel, ' ©From data of J. E. Francis and R. L. Gamble, Phys. Semiann. Prog. Rep. Mar. 20, 1955, ORNL-1879, p 20. 4Values in parentheses are assumed, | ®Preliminary estimate of spectrum; only 20% of the fission products reside in core. /This spectrum was assumed to be similar to the prompt-fission spectrum because it was convenient. The gamma | p promp P g rays from radiative capture in uranium have not been observed and their character is unknown, but they are thought to be multiple rather than a single gamma ray. The spectrum was normalized to the binding energy of the captured nevufron, £30% of the fission products reside in the heat exchanger, headers, and pumps. bNominal 4y2 in. of lead assumed, 20 mg of boron per cubic centimeter of mixture. 2 or more may exist at some energies. It should be noted that only about 20% of the fuel in the circuit is in the core, the remainder being in the heat exchanger, headers, pumps, and core end ducts. The fission-product gamma-ray spectrum is actually unknown. The spectrum used has only a very slight experimental basis. The estimated spectrum given here is probably correct within a factor of 1.6, with respect fo total energy. Several experiments are being performed for de- tiving a more definite estimate,® The capture rates given for the lead and for the hydrogen in the alkylbenzene are based on a numerical volume integration of the thermal-neutron SR, W. Peelle, T. A. Love, and F. C. Maienschein, ANP Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 203. i +h - - peri ment:(c":I - sources. fluxes measured behind a circulating-fuel reactor mockup in the Lid Tank Shielding Facility (LLTSF). This mockup contained 4.5 in. of lead and 2% boron in the water. As yet, the thermal-neutron fluxes cannot be calculated for the reactor in this region, Also, the degree of boration to be used has not yet been determined. Consequently, the capture data for the lead and alkylbenzene are based on the assumption that the fraction of the neutrons captured in the LTSF mockup applies to the reactor, corrected only for neutron self-shielding in the core. SHIELD WEIGHT DEP ENDENCE ON THE DIMENSIONS OF A 300-Mw CIRCULATING-FUEL REACTOR " A parametric weight study that is nearing com- pletion indicates that lighter shield weights for circulating-fuel reactors may result from changes in reactor dtmensmns. The shield weights are belng determined for a fixed reactor power (300 Mw) and a ‘‘standard shield”’ (described below) as a function of power density, islond radius, “reflector thickness, and heat exchanger thickness. The weights obtained will be used as part of the input information in a parametric performance study under way ot Pratt & Whitney Aircraft, The standard shield consists of a set of specifi- cations suff|c1en’r|y representative of tactical bomber shaelds to ensure a realistic reactor op- timization. Some concessions to e-xpedlency were made, such as the selection of sea-level altitude and a recctor-’ro-crew-compartment separation distance of 64 ft, in order to make direct use of the neutron dafa recently ob'rqm_ed at 'rhe Tower Shleldmg Facnllty (TSF) '-f'.-?'r'-ff';i|mpor’rcn’r source eglyc':ns. Because of differences Lo neutron Ieukage between the LTSF mockup i ‘and the desngn’_ reactor, fluxes from mulhgroup;; LTSF were us_ ergies of fhe gammc rays orlglnahng in the various _ ’G. T. Chdpmcn, J. B. Dee, and H. C. Woodsum, ANP Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 194. Tank Shielding Facility'’). ‘créew compartment, “aceording to preliminary results. “*“particular case was chosen for which the neutron - shield weight was close to minimum and for which o~ close-to-minimum lead thickness was required """’on 'rhe crew-compcrfmenf sides, PERIOD ENDING SEPTEMBER 10, 1955 regions, the various dose-rate components were treated separately to account for the different attenuation characteristics in the shielding ma- terials. In considering air scattering, the dose rate from neutron captures near the outer lead surface was treated as a separate isotropic source that was relatively independent of lead thickness. A second difference arises from the use of TSF fast-neutron experimental data for air scattering and crew-cempcrtmem‘ penetration and the use of an optimized shape for the neutron reactor shield and the crew-compartment wall thickness. A third difference arises from the use of a tapered shadow shield. For these calculations, the crew compartment was assumed to be a right cylinder, with an area of 35 ft2 on the rear and 225 ft* on the sides. Plastic and lead were the shield materials used to give a neutron dose rate of 0.25 rem/hr and a gamma-ray dose rate of 0.75 rem/hr in the crew compartment at sea level. The reactor-to-crew- compartment separation distance used was 64 ft. The reactor shield, which consisted of lead and alkylbenzene (330°F), was designed to give a maximum dose rate of 1000 rep/hr at 50 ft (as- sumed radiation damage restriction). The neutron shield was chosen in the following manner, For a typical aircraft reactor (Table 11.2), the fast-neutron dose rate as a function of the thickness of the spherical shield was ob- tained by the application of conventional meth- ods®? to data from the current LTSF circulating- fuel-reactor shielding tests (see Sec. 12, ‘‘Lid For this reactor and an optimization study was initiated at the TSF to determine the minimum- ‘from those mude prev:ously in several respects.m“("'kweigh" neutron shield and its shape (see Sec. 14, One of the dlfferences arises from the use of the_' ~ Tower Shi S “*% the neutron shield weight appeared to be broad ““Tower Shielding Facility'’). The minimum of with respect to degree of division of the shield, Therefore a For this case Becauee of A'rhe fchffe-rent primary en-""""' Report of the 1953 Summer Shieldin Sesszon, ed. by E. P. Blizard and H. Goldstein, ORNi 1575 (June 11, 1954), p 293 ff. 9F. H. Abernathy et. al., Lid Tank Shielding Tests for the Reflector—Modemted Reactor, ORNL-1616 (Oct. 5, 1954), p 79. 189 ANP PROJECT PROGRESS REPORT the plastic thickness at the rear of the crew com- partment was 43 cm and at the side, 14 cm, Be- cause the neutron shielding on the crew compart- ment was unchanged throughout the parameter study, the fast-neutron dose rate at 64 ft from the reactor at the various values of the reactor angle @ (where 0 is the angle measured with re- spect to the reactor-to-crew-compartment axis) - also remained unchanged. A parameter change in the reactor that resulted in a change in the fast-neutron dose rate at any angle ¢ was com- " pensated for by an adjusiment of the neutron shielding at that angle 6 to keep the fast-neutron dose rate at 64 ft constant. In the TSF calcula- tions, the angular distribution of the neutrons escaping from the reactor shield surface was assumed to be éos Y in calculating the direct dose, where ¢ is the angle measured with respect to the normal to the shield surface, while radial emission was cssumed for the calculation of the scattered dose. With the neutron shielding fixed, the gamma-ray shielding was taken to consist of four components: the basic lead shield required to maintain a maxi- mum dose rate of 1000 rep/hr at 50 ft (an crbn‘rary radiation damage limitation); the shaped lead shadow shield adjacent to the basic shield; the lead on the side and front of the crew compart- ment; and the lead on the rear of fhe crew come partment, The shadow shield was arbitrarily shaped to permit the dose emission per unit angle § to increase exponentially to compensate for the exponential decrease in the probability of scattered radiation penetrating the crew- compartment side'® as 6 increased. An approxi- mation for the effect of the angular distribution -of the gamma rays escaping from the reactor - shield surface wds made by assuming a ‘‘dis- ‘ 'cldvanfage angle a (assumed to be 15 deg) when :cclcula’rmg the scattered radiation penetrating the crew compartment. This assumption results in a constant thickness portion of the shadow ‘ shlel_d that subtends d half-angle of 15 deg with ‘respect fo the reactor-to-crew-compartment axis, __._fo_“owfiéd by a tapered section that decreases '(1) D= D) H(a) it e L g ST 10 The scattering-penetration probabilities used were those calculated by NDA; Report of the 1953 Summer "Shielding Session, ed. by E. P. Blizard and H. Gol dstein, ORNL ]575 (June ” ]954), p 188--205. ‘rr o 1 a2 LT 190 c's R —SZtHX linearly in thickness, with the angle 6, until it reaches zero. The tapered section ends at 6§ = 63 deg for a 3.23-in. shadow shield shaped with a 12.5-deg relaxation angle and a 2.1-cm relaxation fength in lead for the primary dosé. The basic lead shield does not have a constant thickness but decreqses from rear fo front 1o compensate for the increased gamma—ay attenuation from the increasing neutron shield thickness along a radial path., | The gamma-ray shield division chosen, under the ‘assumptions outlined above, consisted of 0.1 in. of lead on the crew-compartment sides and approximately 6 in. of lead, ‘in addition to the basic shield for the direct dose, which was divided into a 2.56-in, shield on the crew-compart- ment rear and a 3.23-in.-thick tapered shadow shield near the center; the exact d|v15ton of the basic shield was not sensitive wsth respect to weight, The shadow shield was in direct con- tact with lead in most of the cases considered. . Spacing was. employed, however, for some cases in which the reflector was thin and for which the secondary gamma-ray dose contribution was large. The first step in the weight calculations was to determine the shield necessary to give the design dose rates from the rear of the shaped reactor shield. The design dose rates were 108 rem/hr at 50 ft for fast neutrons (10,8 rep/hr) and 1000 rem/hr at 50 ft for gamma rays (1000 rep/hr), Neutron Shield The neutron-attenuation data were taoken from fast-neutron dose-rate curves obtained at the LTSF by using the Glass-Hurst fast-neutron dosimeters and the Hornyak button. The data were extrapolated for thicknesses beyond the range of the LTSF fast-neutron dose-rate instru- ments by means of thermal-neutron-flux traverses in the LTSF and fast-neutron dose-rate measure- ments at the TSF. Neutron dose-rate curves were available for beryllium reflector moderator regions 8, 12, and 16 in. thick and o 4-in.-thick heat ex- changer region; the data were corrected for air gaps, aluminum tank walls, and Boral regions, The basic neutron-shield thickness was determined from the expression -8, (szo"zAlky)‘Alky e e ' - " D(z) = LTSF fast-neutron dose rate at z where _ D, = fast-neutron dose rate at 64 ft, 6.6 rep/hr, for the particular reflector thickness, z = shield thickness measured from the surface of a sphere representing the core of the reactor, o | H(z) = ratio of the fast-neutron dose from an " infinite plane to that from the LTSF source disk, taken to be (1~ 630/)\(2)2] o= equivalent surface source strength for the LTSF, taken to be 6 w x 0.6 (leakage factor) = 3970 cm?, = equ:vclent surface source strength for the ~reactor, taken to be - s =t /A pA| 1= — e e c ey, o c A_ = reciprocal of the neutron removal cross section for the fuel NaF-ZrF -UF (50-46- 4 mole %) at a density of 3. 2 g/cm , taken to be 11.6 cm, p = power density (w/cm3')', r_ = outer radius of the core (fuel annulus), = inner radius of the core (fuel annulus), r = outer radius of the fofcl réaétor S‘hield, e _‘_. = correction by effechve removal cross R sec ons from the ‘common 4-in.-thick heat ' exc__ 25 vol % Ni, 75 vol % NaF at a dens:ty of t yx = reactor heat exchanger thic kness, VZHX = effective removal cross section for the ) g/cm3 to a 3.5in.-, 65-,,,_ Cor &in. 1h7|_ck heot exchcmger hcvmg a C°mposmon'" y onel X, 273 vol % fuel, , - " “ponents of the LTSF data were available for several - PERIOD ENDING SEPTEMBER 10, 1955 reactor heat exchanger (homogeneized), taken to be 0.0659 em™}, = effective removal cross section for the 2 HX, mockup heat exchanger of the LTSF experi- ments (homogeneized), taken to be 0.0869 em”}, S’H o = effective removal cross. secfion for 2° \ater, taken to be 0.0994 cm™7, EA“( = effective removal cross section for alkylbenzene 350 at 330°F, taken to be 0.0882 5, _ ztR cm e = effective removal cross-section cor- rection for minor differences between the LTSF configurations and reactor configura- tions, tp = sum of thickness differences, —(EHzo‘EAlky>tA|ky ‘ e = effective removal cross- section correction for the substitution of alkylbenzene for water, ' t = thickness of alkylbenzene at the reactor, Alky d = separation distance from reactor center to rear face of crew compartment, 64 ft. Gamma-Ray Shield " The gammeo-ray shield was determined by finding, separately, the gamma-ray dose rate at 50 ft caused by (1) gamma rays emitted by the fuel in the core and by neutron captures in the outer core shell and in the reflector, (2) gomma rays emitted by fission products in the heat exchanger, and (3) neutron 7 _._.captures near the lead-alkylbenzene interface. For nger ‘mockup havmg a composmon of each reactor shield design these three groups of contributions were determined separately and then su rh_mt_ed. Reactor Gamma-Ray Dose Rate. Dose-rate com- fead thicknesses for each reflector thickness (8, 12, and 16 in.). The gamma-ray dose rate data were divided into contributions from the source plate, capture gamma rays from the beryllium re- flector, capture gamma rays from the Inconel core ~ shell, and secondcry gamma rays, principally from " ““neufron captures in the lead, boron, and water near the lead-water interface. The source correction was determined by assuming an exponential power distribution through the natural uranium of the 191 g ] ANP PROJECT PROGRESS REPORT source plate and determining the self-shielding factor, s: : S ! S : L o e t - o 'O s = _ =4,02, ¢ u - — — L] f (}5 e Eaz e ‘uu(tu t) e Fppipy d 0 o where ¢, = thermal flux incident on the reactor side of the source plate, 3, =total thermal absorption cross section for natural vranium, {,, = gamma-ray absorption coefficient, 4 Mev, pps = gamma-ray absorption coefficient for the lead over the source plate, effective source plafe thlckness, 7/4 in., ~~ I i pp = lead thickness, 1/2 in. where i, = effective mass absorption coefficient for the core for a gamma-ray energy of 3 Meyv, t = thickness of fuel annulus, pt,. = typical core fuel annulus thickness in gamma-ray mean free paths, in the natural uranium of the source plate, three- eights of the thermal-neutron captures take place in U238 and give radiative capture gamma rays that are not present in the enriched reactor, Un- fortunately, the energies and associated probabili- ties of emission per capture for these gamma rays are not known. For this study, a total energy of 6.4 Mev per U238 capture was assumed to be emitted in a distribution corresponding to the fission gamma-ray distribution, Similarly, for radiative capture in U235, a total energy in gamma rays of 7.6 Mev per nonfission capture was as- sumed. The fraction of gamma-ray dose attributable to U233, t, in the source plate was then taken to be: E,(235) 3,(235) + E (235) = _(235) -— 2 7 E(235) 5,(235) + E_(235) 3_(235) + E_(239) T _(238) Since only about one-fifth of the fission products are in the core, the core dose rate should be = 0.57 , where E (238) = total photon energy per capture in multiplied by the fraction of energy from the core Y238 while fuel is circulating, ¢,: E _(235) % (235) + Ef(235) Ef(235) + fp(235) Ef(235) = 0.867 , "7 TE_(235) £, (235) + E,(235) %,(235) + E, ,(235) %, (235) where E _(235) = totdl photon energy per capture in U235 7 Er(235) = total photon energy per U237 fission, (235) —photon energy from fission products per U235 ftss:on, EC(235) = nonfission capture cross section for U235’ ' Ef(235) = fission cross section in U235, The reactor gomma-rdy core leakage factor, I, was esnmofed to be: ol L ooars, 2% _(238) = capture cross section for U238, The total scaling factor to be applied to the core source for the same power per unit area of source surface is the product f=sxt, xIxty, =09, The scaling factor for the capture gamma rays from the reflector was obtained as the ratio of the fraction of neutrons captured in that region in the reactor (as determined by application of Eyewash code neutron cross section to Foxcode multigroup - fluxes) to the fraction of neutrons captured in the. same region in the LTSF mockup (as determined by numerical integration of LTSF gold-foil flux DAl i i, LA i AR K&_Lm ' -l S A bl u abie g i, kit i oy M, el o w measurements). This ratio was 0.0592/0.0145 or 4.00. The contribution from the island was calcu- lated to increase this to 4.05, The fraction of neutrons captured in the Inconel core shell in the reactor was estimated in the same manner as that from the reflector and was checked against foil data from the Critical Experiment Facility. The fraction captured in the LTSF mock- up was also determined by integration of gold-foil ‘measurements. The scaling factor for the outer core shell contribution is the ratio 0.0545/0.0161 or 3.39. Similar corrections applied to the inner core shell raised the scalmg factor for the core shells to 3.62. , - For each reflector thickness (8, 12, and 16 in.) and for each lead fhlckness (3, 4.5, and 6 in.), " these correction factors were applied to the com- ponents determined from the LTSF data. The ‘variation of the reflector component of the total gamma-ray dose rate with reflector thickness, as obtained from the LTSF dm‘a, was observed to be in agreement wn‘h the variation for a reactor, as determined in PWA-NDA multigroup calculations, and therefore it was assumed that nonc of the scaling factors changed with reflector thickness, _ The sum of the dose-rate contributions from the source plate, the capture gamma rays from the beryllium reflector, and the capture gamma rays from the Inconel core shell, that is, Dy, (a,z2), for each reactor design was transformed to the corresponding dose from an infinite plane by o B(ut) E ,(u2) N(E) ME) ,u..-— effechve mass cbsorpflon coefflcrem‘ for the shielding materials for a gamma-ray energy of 6.8 Mev, PERIOD ENDING SEPTEMBER 10, 1955 E,(uz) = exponential integral whose argument is the number of mean free paths from the source to the detector, The primary dose at a distance d from the reactor was then determined by the expression: D, (d) rr PR/4n'r3_ cC S — H{a,=) Dp i fla,z) cicqeq d? PLT/mz2 ] It reactor power, 3 x 108 w, 1.7 = LTSF source plate power, 6 w, c, = change in attenuation due to replacing the 4-in.-thick test heat exchanger mockup with a particular reactor heat exchanger composition and thickness (based on exponential attenuation at 6.8 Mev), = change in attenuation due to addition of small claddings, correct pressure shell thickness and composition, etc. (based on exponential attenuation at 6.8 Mev), = change in attenuation due to substitution of alkylbenzene-350 at 330°F, assuming that . = 0.8 py 0! based on electron density. Heat Exchanger Dose Rate. The dose rate from the heat exchanger was calculated by using the following expression: T HX, i L /ME) AE) ~t ./ AME) R ’Hxi Tux o dE , 2C(E) = volume fraction of heat exchanger that contains fuel, = volume of fuel in total circulating ) system, U"‘:""‘=:?oui's ide rodlus of heu’r exchanger, = inside radius of heat exchanger, fission product gamma rays of energy E emitted per unit energy per fission (taken to be 7.0 e~ 1+2E) (see Table 11.3), 193 T - . »‘.E‘ ki ANP PROJECT PROGRESS REFORT C(E) = number of phofons‘ of energy E " equal to 1 rem/hr, 1T E}'(pi) = exponenhal integral whose argu- ~ment is the shield thickness in . mean free paths, B(uz) = the dose buildup factor, ‘tHx = heat exchanger thickness, ME) reciprocal of gamma absorption “coefficient for a mixture of the R mcn‘erla Is in the heat exchcnger, 3] X ]0]0 = number of f:ss:ons per second - per watt, The above 1nfegral was evaluated numerically \.:-,over a range ‘of thicknesses for the heat exchanger, - lead, cmd water, and it appeared to be valid over the range required to separate the self-shielding - factor from the remainder of the integral. An " average " self-shielding factor was derived which depended only upon the heat exchanger thickness and which was in agreement with the more exact integration to within 7% over a range of lead thicknesses from 0 to ¢ in. and a range in water thicknesses from 40 to 100 cm. Thus, to simplify the calculation procedure, the integral was broken up into the following product: where tp, = reflector thickness, tpy = lead thickness, Eatky = dlkylbenzene thickness, Top = radius to outside of lead, -~ H(a’,t) = lead surface neutron source to infinite plane neutron source trans- formation calculated by ratios of exponential integrals, as before (from LTSF flux traverses, a’ is dpproximately 45 cm), H(a,zpb) = lead surface neutron source to infi- “nite plane neutron source frans- formation, taken to be . -84/z /(1 - e Pb) t;, = thickness of coohng luyers in the lead basic shield, ’\l = relaxation thickness of cooling layers for secondary dose (deter- mined to be 5.33 ¢m from correcting LTSF data for spaced lead by the AMEY | T = r HX HX o Q The first expression represents an average self- shielding factor as a function only of the heat exchanger thickness., Evaluation of the second factor for a series of lead thicknesses results in a curve of gamma-ray dose rate as a function of lead thickness for an infinite plane source of fission products, Secondary Dose Rate. The secondary dose rate (from captures in the lead, boron, and hydrogen near the lead-water interface) was determined by scaling the neutron dose rate in the source region (lead-alkylbenzene interface) as follows: "‘,:.‘Ds(d) = Dg_; rltgertppitap,) Hla ,ztA“W)—---*—-——d2 Hla,zp,,) = 194 HX; 1, /MEY ME) [ =t/ ME) : HX + ()(e HX __1) * B(pz) E,(ut) N(E) - dE . 2C(E) effective removal cross sections for alkylbenzene), = ratio of reactor to LTSF equivalent LT surface source sitrength for neu- trons, ' ”Calculated from an expression in ORNL. CF-51-10- 98 [F. L. Culler, EBR Fuel Element Design {Oct. 15, 8951)] and from absorption coefficients in NBS- 1003 G. R. White, X-Ray Attenuation Coefficients from 10 kev to 100 Mev (May 13, 1952)1 "ob's e %R _;,/Al"' | b LT _: 2 ' - _ Lol : PERIOD ENDING SEPTEMBER 10, 1955 1 3 7 4"-::%.71;:: ' weigl‘lf Deiermiridtidms ’Cre"fi"compartfilehf plastic 9,900 The weights determined include the reactor, Crew compartment rear lead 3,270 h { - pumps, heat exchcngers, reactor shield, crew- Crew compartment side and fronf. lead 1,530 b compartment shiel_d, .shcdow shield, structural Total Crew Compartment - 16,700 - ‘weight, and pc:’rch weight, For example: Toral System 70,000 'Reactor No 3232 ' ‘ d " Power density _ 4.125 kw/cm> Variations of this total system weight are shown " Reflector fhlckness o 12 in. in Figs. 11.3, 114, 11.5, and 11.6 with respect to " Tsland radiu's [ S T variations in island Vrcxdius, power density, heat e Heqf exchqnger fhlgkness T 6.50n. exchanger thickness, and reflector thickness. 7 ; Welght (lb) 7 . " Pressure shell and con'l'enfs]z 22,970 12} cludes all layers of materials, in addition to . ‘ - _ : o .- pumps and drives, control rod and island support, i * : y Alkylbenzene L o _ - 6,650 sodium~to-NaK heat exchanger, manifolds, decking, h ' ' Basic lead shell = - 14,740 ducting, and expansion tanks. i Patch v_ve'iéhf S 3,230 ' | E ) Structural weight o o 1,910 7 s Shadow shield 7 3,800 85 2-01-059—-24 " Total Reactor cmd Reactor Sh:eld Welghf | 5.3;,300 7' 80 e 2—01—059—23 R | I, ] I ; . . : . je} o POWER. DENSITY = 4.125 kw/cm® % \ o HEAT EXCHANGER THICKNESS = 6.5in. 2 _ , B . . S ° . ‘ b: o REFLECTOR THICKNESS =12 in. = 80 -y ! : g & o : ¥ HEAT EXCHANGER THICKNESS = 6.5 in. * % . / E , REFLECTOR THICKNESS =12 in. 5 L & ISLAND RADIUS = 4.0 in. ; = " P £ ) 3 \ O o g P o o T o R . L a; : 9 S 2 z o . g i 6 70 — Ly - & S o 70 Tk o O < ' 5 L 1»—-‘_-/ % ' Q G @ st ... 0 1 2 3 4 5 6 i i e oy s . POWER DENSITY (kw/cm3) ' { “ISUAND RADIUS (in) : o , i - - Fig. 1.3, Total Weight vs Island Radius for Fig. 11.4. Total Weight vs Power Density for e ~ 300-Mw Circulating-Fuel Reflector-Moderated =~ 300-Mw Circulating-Fuel = Reflector-Moderated Reactor. Reactor. 195 ANP PROJECT PROGRESS REPORT . 75 2-04-059-25 2-01-059-26 ) 80 | _ T T =3 - REACTOR, REACTOR SHIELD; AND CREW COMPARTMENT WEIGHT (b x 10 / i pda & ~ w 65 Z " POWER DENSITY = 4.125 kw/cm® REFLECTOR THICKNESS =12 in. ISLAND RADIUS = 4 In. o o 60 3 a4 5 6 7 8 9 POWER DENSITY =4 .125 kw/cm3 HEAT EXCHANGER THICKNESS =6.5in. ISLAND RADIUS = 4.01n. REACTOR, REACTOR SHIELD, AND CREW COMPARTMENT WEIGHT (ib x ‘TO_'3) : ~ o HEAT EXCHANGER THICKNESS (in) Fig. 115. Total Weight vs Heat Exchanger Thickness for 300-Mw Circulating-Fuel Reflector- Moderated Reactor. 60 6 8 10 2 14 16 18 REFLECTOR THICKNESS (in.) Fig. 11.6. Total Weight vs Reflector Thickness for 300-Mw Circulating-Fuel Reflector-Moderated Reactor. 196 e e . % * PERIOD ENDING SEPTEMBER 10, 1955 12, LID TANK SHIELDI'NG«F3AC1LITY G. T. Chapman J. M, Miller ~ Applied Nuclear Physics Division W._ J. McCool H. C. Woodsum Pratt & Whitney Aircraft - The static source tests of the second series of the circulating-fuel reflector-moderated-reactor and shield (RMR-shield) mockup experiments at the Lid Tank Shielding Facility (LTSF) have been com- pleted and the data are being analyzed. Tests with the dynamic source are in progress, REFLECTOR-MODERATED-REACTOR AND SH!ELD MOCK UP TESTS Fur'fher variations were made i in the mockups of | fhe RMR- shleld for 'rhe final measurements in the stm‘lc source tests, ! Gommq-roy and neutron measurements: were made in the water beyond the mockups, and sodium activation measurements ‘were made within the heat exchanger regions of the mockups. Gummu- Ruy and Neutron Measmements - Beyond the Mockups Neutron and gamma-ray measurements were made in water beyond the RMR-shield mockups to de- termine the effect of placing an intermediate or high atomic weight material immediately behind the beryllium reflector, varying the thickness of the reflector, and d:stribufmg the lead gommo-roy shield in borated water, The effecf_of placing an lnfermedmfe or hlgh ihdterml |mmed:a1rely behind the _'freflec’ror fegion was studied by’ cdohng a 3-|n.-fh|ckh ~ slab of blsmi_q“h 'IThe first measuyrements were reporfed by G. T. Chapman, J. B. Dee, and H. C, Woodsum, ANP Quar. Prog. Rep. June 10, 1955, ORNL-1896, p 194, o u nick slab of ‘copper be- S - hind c:n_fl8-m2lfh|c|< slab e}f berylhum.' An onalysrs{" R %,\but unforfunate y‘, there was'_’f“;-; ' used to allow apprec:oble sel}f-;_v _obsorphon of capfure gamma rays; fhe fcst neutron dose rate was the same as that for an equivalent thickness of beryllium, Although the 2-in.-thick layer of copper would not be sufficient to effect an appreciable weight saving, there might be enough self-absorption of capture gamma rays in a 4-in.-thick layer to show a valuable weight saving. The effect on the total gomma-ray dose rate of varying the beryllium thickness (8, 12, and 16 in.) was not appreciable. There was greater attenuc- tion of the source gamma rays by the larger berylli- um thicknesses, but more capture gamma rays resulted from the beryllium, Fast-neutron dose rates were not very different behind the various thicknesses. A study of the effects of distributing the lead gamma-ray shield in borated water was also made in order to obtain the information needed for an optimization of the placement of the lead, This study showed that there would probably be no weight saving as a result of distributing the lead rather than placing it in one piece, for lead thick- nesses up to 5 in., but that there might be an ap- preciable weight saving as a result of distributing the lead beyond the first 5-in. layer. The secondary gamma-ray dose rate produced in the lead and borated-water shield fell off at the same.rate as the thermal-neutron flux and thus was apparently " caused by thermal-neutron captures in the shield. -+ Sodium Activation in the Heat Exchanger Region of the Mockups Sodtum activation tests were performed to de- ll termlne the achvcmon of the coolant in the heat exchanger region as a function of the heat ex- " ) chcmger thickness, the boron curtain thickness and d:sfrlbuhon, and the reflector thackness. The ef- | fect_on the achvahon of p!acmg a copper gamma- ray' shield ‘immediately behmd the beryllium reflector was also studied, The sofurated specnflc ochvmes in the heat exchcmger regions were measured in the manner described previously! for a total of 17 mockups, 5 of which are shown in Fig. 12.1. If only two heat exchanger tanks were used in a test, a 197 ANP PROJECT PROGRESS REPORT 2-01-057-66-160 10 ~ \l ™ \\ 5 \= 3N\, \ll > N, —_ & % e e . 'g 4 \a \ g0 e N & ™ N2 = oA A 2 \\ - x5 N 3 |_® REPRESENTS MEASUREMENT _ &\? 5 APPROXIMATELY IN CENTER s — OF HEAT EXCHANGER TANK —--=8=m i _ . . ; | &2 & 5 \° K 3 % 10 [T_ CONFIGURATION MOCKUP SYMBOLS ] (] - . — 2~in.-THICK Nof TANK — ¥ -in.-THICK BORAL S SHEET s 2-in.- THICK COPPER | SLAB . % MOCKUP 5 HAD A {2-in.- THICK BERYLLIUM REFLECTOR ; 2 MOCKUPS 1 THROUGH 4 HAD 8-in.- THICK BERYLLIUM REFLECTORS sl 25 30 35 40 45 50 55 2, DISTANCE FROM SQURCE {cm) Fig. 12.1. Sodium Activation in the Heat Ex- changer Region of the RMR-Shield Mockups as a Function of Distance from the Source. straight line was drawn through the two points because of the lack of more information. Addi- tional information probably would show these curves to be slightly concave downward, as in the 198 cases where three heat exchanger tanks were used, The five tests shown in Fig. 12,1 are representa- tive of the results obtained to date. A more com- plete analysis of all tests is being prepared. If test 2 is used as a reference, comparison of the activations in the different tests shows the effect of adding or removing different components of the configuration, In tests 1 through 4, 8 in, of beryllium was used to simulate the reflector, while in test 5, 12 in. of beryllium was used. Comparing test 1 (4-in.-thick exchanger) with test 2 (6-in.-thick heat exchanger) shows that there is greater relative activation in test 2; this results from the reduced resonance-neutron escape probability in the thicker heat exchanger. The escape probability may be increased simply by distributing the boron curtain through the heat exchanger region, [n test 4, a distributed curtain containing less curtain material reduced the total activation to about 25% below that found in test 2. An increase in the reflector thickness from 8 in. (test 2) to 12 in. (test 5) effected a decrease in the sodium activation of about 80%. This was due to two effects: an inverse-square spreading and a reduction by the extra 4 in. of beryllium of the number of neutrons at and slightly above the sodium resonance energy of 3 kev, » fn test 3, o gamma-ray shield of copper was placed between the beryllium reflector and the first boron curtain. The sodium activation was increased by a factor of roughly 6, in comparison with the activation found in test 1 with no copper present in the reflector, The copper apparently changes the fast-neutron spectrum so that there are relatively more neutrons at or just above the 3-kev resonance level of sodium. The boron curtain is only gray to neutrons of this energy, and, hence, some of these neutrons diffuse through the boron curtain into the heat exchanger, where they are slowed down to the 3-kev resonance level by the fluorine. T T o ’range of decay hmes. CTL V. Blosser G. M. Estabrook J.D. P .M, Henry A 7. Fufl'erer PERIOD ENDING SEPTEMBER 10, 1955 e W 'BULK SHIELDING FAGILITY S s R, Ma:enschem - E. B. Johnson T. A, Love F. J. Muckenthaler R. W. Peelle W. Zobel Apphed Nuclear Phys:cs Division K. M. Johnson Prafl' & Whn‘ney Anrcraft The angular—dlstr:buhon measure=ments of fdst neufrons have been extended to include measure- . “‘ments’in a plain-water medium. The resulhng data " have been correlafed with the TSF shield Op‘l‘!ml- o "zahon studies, The first portion of the expeti- *“menfs designed for defermmmg the ‘spectrum of 7,f_”flsmon-producf gamma rays was comple'red for one ' "li,’ANGULAR DISTRIBUTION OF FA T NEUTRONS s . 'THROUGH WATER ) T V Blosser, Appllecl Nuclear Phys&cs Division M E Valermo, NACA Cleveland : A seties of shleld ophmlza'non sfud:es is bemg ~‘made at the TSF, and for such o rational deter- ~ mination of the neutron shielding lhlcknesses re- qu;red at the reactor and at the cre'w compartment | - ofa nuclear—powered aircraft, it is necessary to ; know the angular distribution of the fast-neutron [ dose at fhe reactor shield surface. Some prellml- _ ndry méasirements have therefore been ‘made at r {f" i’rhe Bulk §_h|e|d|ng Fac:llfy (BSF) to obtaln anh T f{jrmdlcaho/n of the angular dlsfrlbuhon of the fast: "background’ from neutrons orlg:nahng in the line. Some uncertainties exist in the interpretation ¥ _ ~of the measurements because of the unknown water along ‘rhe sides of the collimator and scat- teted by the collimator into the Homycdk button, This background is expected to result in a broader angular distribution than actually exists, The arrangement, in the pool, of the air collima- tor, the fast-neutron detector, and the lead detec tor housing, relative to the reactor, is shown in Fig. 13.1. The active lattice of the reactor is a 5 by 6 fuel element array with two fuel elements missing from the back (south) corners of the lattice. The air collimator is a hollow cylindrical aluminum tube 168 em long, 5.08 e¢m ID, with a 0.16-cm wall, The position of the end of the colli« mator toward the reactor is given by coordinates (z,x), and the collimator angle, with respect to the reactor center line, is designated by the angle a, as shown in Fig. 13.1.- Measurements were taken only in a horizontal plane at the mid-plane of the reactor. The angular distributions were measured at the following locations in the pool water shield: = 70 crri, x = 0; 70 cm, x ). “,7‘ N ] Thefwoangles, d] and a2, at which a pro;ec- ‘ tion of the axis of the collimator just intersects the two edges of the north face of the reactor are 199 I o i S i s . g . . o e s ‘ EY -, v b e e e ANP PROJECT PROGRESS REPORT ORNL-LR-DWG 8553 REACTOR . (LOADING NO. 33) ~=-19,6 cm = a, s, 7.6 cm OF LEAD 5.08-cm |D HORNYAK SBUTTON H, PHOTOMULTIPLIER DETECTOR HOUSING AND SHIELD Fig. 13.1. Experimental Arrangement for Meas- urements of the Angular Distribution of the Fast- Neutron Dose in the Water Shield of the BSF Reactor. indicated i:ri Fi'g.' 13 2. For the rdn'gétdf the qngles lli[between OL] ‘and’ a,, the collimator sees some por- - tion of the active lattice. It may be seen in Fig. _ "3’13 2 that in thls range of angles the variation in - .the dose rate per unit solid angle is small, Be- “of the relatlvely poor statistics in these o r;'mecsurémenfs, the exact nature of the variation is - “not defined. For angles outside the range o',1 and dq, the pr0|ected axis of the collimator does not infersect any portion of the active lattice. In this . .region, the measured dose rate is principally from o ii_neutrons which have made at least a single colli- - ~ sion in fhe water sh[eld and therefore, as the col- limator swings away fi'om the reactor face, the ‘dose rate per unit solid angle drops rapidly. 200 ORNL-LR-DWG 8954 WIDTH OF REACTOR . 39.2cm Q, Q, CORRECTED FOR BACKGROUND BACKGROUND DOSE {mrep/hr-w- steradian) o! n -80 -60 -4Q ~20 c 20 40 : Q (deq) Fig. 13.2. Angular Distribution of F'ds"t‘r Neutrons (Z=70cm,x=0), ) : e B o The results obtained for z =70 em, x = +19.6 cm ‘are presented in Fig. 13.3, In this case, the pro- ‘jected axis of the collimator at @ = 0 just inter- " “sects the northwest comer of the active lattice. Agam only a relatively small variation in dose rate per unit solid angle is indicated over the range of angles where the collimator sees the active lattice, and there is a relatively fast varia- tion as the collimator swings away from the active lattice. < S , The results for 2 = 5 cm, x = 0 are given in Fig. 13.4. Over the entire range of angles covered in these measurements, the collimator saw some portion of the active lattice, The variation over the entire range of angles is relahvely small and™ is consistent with the results shown in F:gs. 13.2 and 13.3. However, the error m:ght be very icrge for this 5.cm measurement because of the lack of complete collimation. - PERIOD ENDING SEPTEMBER 10, 1955 ' SR ORNL-LR-DWG 8955 105 ORNL-LR-DWG 8956 WIDTH OF 1 REACTOR T 39 2c¢m {. Q, 15 ¥ ORRECTED FOR BACKGROUN BACKGROUND- BACKGROUND NEGLIGIBLE " DOSE: (mrep /hr-w- steradian), c OOSE (mrep/hr-w- steradian) -80 -60 -40 -20 -10 20 40 Q {(deg) _ Flg. 33 3 Angular Dlstrlbuhon of Fosf Neutrons ’ (= 70 cm x'- +'|9 6 cm). : Fig. 13.4. Angular Cistribution of Fast Neufrons L D -~ (z=5¢em, x=0). An mtegrahon was made ‘of the dose rafe per it solid 'r bta fhetfad erat di- L . . um so : ongle o o "n o0 I 22 .,.e m : gross fission products for short times after fission ‘was discussed previously.] A large share of the gamma-ray dose in a CIrculahng-fuel reactor Ol'lgl- £« '7,-.,«1 T o T ar ioadlng by 3 > iminary résu]ts are presefited her “The ugémma-roy decay rate'qs a fuhchon of hme_' E. C Cqmpbe“ Ph.);sws DIVISI;)H ' The |mportonce of information about the decay ]R W Peel[e ot al., ANP Quar. ng Rep June 10, ) chqrqcfe_rlshcs and photon energy spectrum of the 1955, ORNL-1896, p 203. - Lok ANP PROJECT PROGRESS REPORT ma-rdy Qbeci'romefer,2 'rhe qssocmted e!ecfronlc' | instrumentation 'described previously,3 especially : constructed timing devices, and the fcst pneumatic probe assembly designed by E. C. Cumpbell Small, enriched-uranium samples that weighed 7 about 7 mg were irradiated in the ORNL Grdphn‘ef " Reactor for times rangmg from 1 to 8 sec. From 10 to 50 samples were required to obfain a single decay curve, Each sample was withdrawn pneu- - matically in about 0.4 sec and stopped, automati- , 'colly, in front of a 10-in. lead collimator that led .- to the multiple calibration sources. These abso- lute source strengths were obtained with the cali- brated high-pressure ion chamber of the ORNL Radioisotopes Control Laboratory. 2F C. Maienschein, Multz le-Crystal Gamma-Ray Spectrometer, ORNL-'|'|42 (Aprn 14, 1952). 3T, A. Love, R. W. Peelle, and F. C. Malenschem Electronic Instrumentation for a Multiple-Crystal Gam- ‘ma-Ray Scintillation Spectrometer, ORNL-1929 (to be <7~ published). T%’"”&nclyms of fhe 'aotq- was '-s'frdi"gl'if'foi'wo\rc-i : ~except f for the problems of absolufe efflmency of fissions occurring in the scmples. For this pre- llmmary analysis, large uncerfomhes were per-' "“mitted in these two factors. Al’rhough the efficiencies at eherg'ies up to 1.3 Mev were measured for fhls unolysrs, the efficiencies at higher energles were found largely by comparison with previously ‘obtained perform« “ance data, [t is therefore to be dssumed' that a further analysis of these data would gtve a shghfly_ ' “different result. A further dlfficul’ry arises from the wide vonoflon of fhe Specfrometer effic:ency' VW|’rhm a single energy group. The average efi‘l-_ | ciency was used here, but the spectrum shape within a given energy group should be used to _ :obtam a welghted average effncnency. 7 izati n_ of the results de- The absolute normcl' , pends upon the number of fissions in the samples, which, in turn, depends upon several doubtfu! quantities. For the l-sec bombardments, the time spent by the samples in the reactor is in doubt by at least 10%. The thermal flux and the macro- scopic cross sections of the samples are also in doubt. The effective thermal flux available to the sample was measured by using gold foils and a cadmium-difference technique.* Thermal cross sections were used for both the gold and U235, The basic results of the dqta analysis are shown in Fig. 13.5. Six energy groups were studied, but the region between 1.6 and 2.3 Mev was studied with both the Compton (two-crystal) and pair (three-crystal) spectrometers. [t was expected that these curves might not agree in a preliminary analysis, because it is in the region studied that the efficiencies of either type of spectrometer vary most rapidly with photon energy. The times after fission were measured from the center of the lrra-, - diation time interval. In the pair spectrometer runs, it was necessary fo use an irradiation time of 8 sec, and therefore sa'rurahon effecfs pre|ud|ce the first few points on these curves. Two cross plots of Flg. 13.5 that give the': S photon energy specfrum as measured 20 and 150 sec after fission are presented in Fig, 13.6. The results obtained by integrating the curves of Fig. 13.5 to obtain the total energy release per - 4John Moteff pnvote communlcahon B i Moo ! | i | [ Wy " e PERIOD ENDING SEPTEMBER 10, 1955 fission between 10 and 150 sec are given in (Mev) per fission in this interval must, for the Table 13.1. Because of the uncertainties men- present, carry an estimated probable error of about tioned, the total photons per fission and the energy +25%. UNCLASSIFIED ORNL—LR—DWG 8957 -1 10 5 2 ® COMPTON SPECTROMETER A PAIR SPECTROMETER —2 10 5 - . Q o 2 5 2 0.28 TO 0.5% Mev v Z 054 TO 112 Mev QO 2 o~ g 1.12 70 1.62 Mev 3 = o b S 162 TO 2.3 Mev x 1.62 TO 2.3 Mev % O w o 2 2.3 7O 3.5 Mev 1074 3.5 TO 5.0 Mev 20 \ 220 S CTIME AFTER FISSION 1sec) 77 7 e oo n of Time After Fission for Six 203 ANP PROJECT PROGRESS REPORT UNCLASSIFIED “ ORNL-LR-DWG 8958 T e - COMPTON SPECTROMETER —m— =~ = PAJR SPECTROMETER b Akl DECAY RATE ( pho’rons/Mev . sec fission} 0 10 20 30 40 50 6.0 PHOTON ENERGY (Mev) ' Fig. 13.6. Histogram of the Fission-Product Photon Energy Spectrum for 20 and 150 sec After Fission. TABLE 13.1. MEASURED VALUES OF PHOTON INTENSITY PER FISSION AND TOTAL ENERGY RELEASE PER FISSION INTEGRATED BETWEEN 10 AND 150 sec AFTER FISSION Energy Range Photons per Energy per Energy Range Photons per Energy per (Mev) - Fission Fission (Mev) (Mev) Fission Fission (Mev) . o Cc;m;;fon :Spéé.fromefer - Pair Spectrometer - 0.28t0 6.51- | | | 0.25 0.10 1.62 to 2.3 0.13 0.26 0-.'51716 1:12 | 0.45 037 2.3 to 3.5 0.069 0.20 - 112 f0 1.62 B | 0.22 0.31 3.5 to 5.0 0.038 0.16 162t 23 | 0.19 10.38 Total 0,28 to 5.0 1.19 1.46 o L AvOs A 032 i - 1 - e oo PERIOD ENDING SEPTEMBER 10, 1955 g 14, TOWER SHIELDING FACILITY C. E. Clifford F. L. Keller F. N. Watson Applied Nuclear Physics Division J. E. Van Hoomissen, Boeing Airplane Co, M. F. Valerino, NACA, Cleveland In a previous report! an analysis of the fast- neutron measurements of the differential shielding experiment at the TSF was presented. In this analysis the probability of the air scattering of neutrons into the various sides of the crew- compartment shield was obtained as a function of the angle 8 which a fast-neutron beam from the reactor shield surface makes with respect to the axis joining the reactor and the crew compartment, It also gave the probability of neutron penetration " through the shield into the crew compartment as a function of §. These probabilities have now been used in the development of a procedure for opti- " mizing the neutron shielding of a dwnded shield for an aircraft, 'A further mveshgahon of the GE-ANP reactor and crew shield mockups was also made. Measure- ments of gamma-ray doses inside the crew- compartment mockup were completed, and, at present, a study of the distributions of gamma-ray intensities around the reactor shield is bemg made. PROCEDURE FOR USING TSF DATA FOR THE OPTIMIZATION OF A DIVIDED NEUTRON SHIELD 'M F \Valerlno ' o " would have the minimum welght that w wcs cons:sfenf:';f:' | “with_ all the desrgn parameters._ As a first step in _‘fhe des:gn of a completely ophmlzed ‘neutron shield, ocedure hus been developed to de?ermme, for:f'f‘ " onical s shel!s, as shown in Flg. 14. ]W'L“The ve”ex.-:.ug:;-,,;.;..: S i‘z;;'-\':of each cone IS token to be clf the center of the Y o M. F. Valerino, ANP Quar. Prog, Rep. June 10, 1955 ORNL-1896, p 206. reactor, The radius ¢ in Fig. 14.1 is the radius of the reactor, heat exchanger, gamma shield, etc., and thus the outer radius is the 'sum of radius a and the neutron shield thickness T ., The crew shield is assumed to have a rear thlckness T and a side thickness T_, For simplicity, and because of the small sacrifice in shield weight involved, the front thickness T{ is taken to be equal to the side thickness T _, The procedure consists, first, in expressing both the total weight of the neutron shield and the dose rate at the center of the crew compartment as functions of T , T, and T ; second, of using the method of Lagrange multipliers to obtain the equations which T , T, and T_ must satisfy in order that the weight be a minimum for a specified total dose rate; and third, of developing an iterative procedure for the solution of these equations. Calculation of Shield Weight The weight, W_, of the neutron shielding ma- terial included in the nth conical shell at the reactor is given by - . 2mpg nV - (COS Gn"-—- cos Gnl'l) [(Tn + CZ)3 - a3] A(6,) iy 3 ~ a3 , e where pp is the density of the shielding material to at the reactor; the angles 6, -, 6+, and g, for the nth conlcql shell are |dent|f|ed in Fig. 14.1. The ,fofol welght of shleldmg ‘material at the reactor is thus n=1,2e00,N. The model assumed for the cylindrically shaped crew compartment is also shown in Fig., 14.1. The 205 T T T Y IR e ANP PROJECT PROGRESS REPORT REACTOR SHIELD 2-01—056—-7-D~165 CREW COMPARTMENT SHIELD L oy THREE-DIMENSIONAL VIEW OF AN CONICAL SHELL S I~ o o Fig. 14.1. Divided Neutron Shield Model Used for Optimization Calculation. | weight, 'WC_S', of such a crew shield is given by TP @) W, = {Df_(Tr +T,) * [(Dc + 2Ts)2 - Dg] Lc} ! where P.s is the density of the shielding material used at the crew compartment; D_ and L_ are [defi'ned_ in Fig. 14.1. The total weight of the neutron shielding material is thus (4) o Wiotal = Wp + Weg o 206 Calculation of Dose Rate Let D j(a,4) be the direct-beam dose rate a‘r":'a distance { ft from the unshielded (T, = 0) sphere of radius @, The dose rate at a distance ffi_fl‘fo[‘q o uniform shielding thickness T, is then given by ..fT" (1/A)dt (5) Dad)e ~° ' where A, the direct-beam relaxation length, is « function of t (dt is the increment of T ), The rate at which the dose is scattered to the side of the T T TR (R O VRTIO AN, SR A . e wr " o, € wflbox, cnd {5 is the ‘‘focusing factor’ for the crew compartment from a conical shell is given by! . 8.’ (6) fc“’ " p’ps., (6) d{cos 6) , 058 »e n where D7 is the dose rate at the surface of a hypothetical unit sphere at the reactor and P, . (6) is the probability of scattering into the crew com- partment side from a conical-shell beam, as de- termined from the TSF differential experiments, In the present case T ..f 7 /A )dt (7)-, D5 = 42 Jalye ~F . Thus, if PS.. (8) is considered to be constant over a given conical shell, the integration gives the rate at which the dose is scattered to the side of the crew compartment from the nth conical sBeH as (8) (cos 0,- — cos §,+) Dd(a,fl) X T —f i (I/Ad)dt x € ° /E })zlt:le(6 ) . The contribution to the dose rate at the center of the crew compartment by neutrons which leave the nth conical shell and scatter into the side of the crew compartment is given by (9 D:'Side = (cos 0, — cos 0,,+) x T _f " (1/A)de X Dd(a,fi)e ° X L S )fi?:,de(e )fS P o whlch is a funchon of 9 k% (dx s fhe increment of T ), is the relaxcmon - length for the sccftered ‘dose at the side of the AV::""wher_e )ls 112 e- scattered radiation, The “‘focusing factor décounts for ’rhe radmhon Focusmg in the center of the crew compartmenf cnd depend: on the angularv ; "‘2_J. E. Fculkner, Foc:usz'ng of Radiation in a Cylin- f'irz'ca;l Crew Compartment, ORNL CF-54-8-100 (Aug. 18, 954). Tn, and PERIOD ENDING SEPTEMBER 10, 1955 distribution of the radiation, at the inside surface of the crew-compartment side shield. An expression similar to Eq. 9 holds for the contribution to the dose rate at the center of the crew compartment by neutrons which leave the nth conical shefl at the reactor and scatter into the rear of the crew compartment. This expression is (]0) Dzrreur = (COS Qn; — COS 672”) % T _f n (I/Ad)dz )(l Dd(a,'fl) e 0 X T ..f T (/A)dy 0 x AP}, (6,) 1. e : where A7, which is a function of §,, T , and y (dy is the increment of T ), is the relaxation length for the scattered dose at the rear of the crew com- partment, The factor /7 accounts for a decrease in the dose rate at the center of the crew compart- ment caused by the angular distribution of the neutrons leaving the inside surface of the shield at the rear of the crew compartment. Finally, the dose entering as a direct beam from the reactor through the rear of the crew compart- ment shield must be considered. Let the angular distribution of dose from an element of area at the surface of the reactor shield be of the form cos™ i, where i denotes the angle between the normal to the surface element and a given direction. If it is assumed that the separation distance be- tween the reactor and crew shield is large com- pared with the outer radius of the reactor shield and that the nth conical shell is in the hemisphere toward the crew compartment, it may be shown that the contribution of the nth shell to the direct- beam dose arriving at the rear of the crew com- partment is given by (”) (éosmfl 0, - cosm” Bn”) X . ._f n (1/A y)dt x Dyad)e O . If the shell is in the hemisphere away from the ~crew compartment, the contribution of the shell to the direct-beam dose is zero. If the nth conical shell is in the hemisphere toward the reactor, the rate at which the direct-beam dose leaves this 207 ANP PROJECT PROGRESS REPORT shell and arrives at the center of the crew compartment is given by | B ;f (1/A pdt _f (1/)\ ydy (12 Di'rear =. (cosm-fl Gn' - cos m+'l 9 ) d(a /fl) e f"d e ~ 0 ‘ where A7, the relaxation length for ’rhe darect beam dose at the rear of the crew compartment, is a T, TS, cnd C (L.ag.rcn;tg'e ;nultiplier): aw aD Calculahon of Mlmmum Shleld Welghf for Spec:hed Dose - The th:cknessesT T , and T are considered as parameters whose vqlues are fo be determined so thatW, .. isa minimum when D ., is a specified dose rate, By the method of Lagrange multipliers, this amounts to solving the following (N + 3) simul- taneous equations for the N values of T, and for 208 function of T,2 and y. The factor f7; accounts for total 1 total - the decrease in dose rate of the direct beam at the 3T + T o =0,»n=1,2,...,N, center of the crew compartment caused by the n n angular distribution of the direct-beam neutrons ow oD leaving the inside surface of the rear of the crew ..__l?_f.i + _]_ __total =0, compartment. | the nth conical shell is in the (14) dT, C dT, hemisphere away from the crew compartment, then . D . D‘iv'e‘" = 0. The rate at which the total dose total +_l total 0 arrives at the center of the crew compartment is aT', o aT ’ therefore D,mm, C (specified constant) , (]3) Dfoml For the calculation it is convenient to attach a subscript to the { involved in each equation, but N it must be remembered that, for an exact solution, z z (DSeside pS.rear Dd,reur) all the s must be the same. When this is done -1 " ” " and the differentiation indicated in Eq. 14 is carried out, the following (N + 2) equations for the £'s are obtained: : fota i/aT Di,Side + D;s‘l,reuf + D;zz’,rear ‘ (15) L = = , n=1,2,.00, N, W 10t/ 9T, AA00) (T, + a)? (16) € Droral T '3 0 - ’ ° anofa I/aTs fotc: I/aT n=|\ )\f} . | aDtotal/aTr 1 N Dz,rear Di,rear I =l ) . . ' awtpto I/aTr tota l/aT n=1 )t; )t; The complexfiy of the sysfem of equohons de- rived above requires an iterative mode of solution, and a procedure was desired that converged rapidly enough for the solution to be accomplished in a reasonable length of time by hand calculation, A satisfactory procedure was devised and is de- scribed below in a detailed, stepwise fashion. Step a. Equations 16 and 17, with the condition | fir =L =L, are combined to relate £ to the speci- [ o M S\ b el aans N fied dose rate, D__. . (given by Eq. 13), and to appropriately averaged relaxation lengths. In- cluded in this relationship are the shield-weight partial derivatives with respect to T, and T_, which are known functions for a given crew- compartment size, These steps are shown below in equation form. If the following definitions are made, N » E Dz's‘de//\i 1 “ _ = N ' AS ,s id s z Dz side ' n=1 (18) N S, ,rear /) 7 -I E Dn /)\s n=1 = ’ N N A7 , s z:l)irecr n=} then Eqs. 16 and 17 may be combined to give PERIOD ENDING SEPTEMBER 10, 1955 Equation 21 gives L in terms of quantities which are either specified or determined from the previous iteration, For the first iteration, fairly accurate estimates can be made of the values of the quan- tities in Eq. 21. Since D?‘f"“' << D, .oy and AL/AG ~ 1, X, will be approximately equal to 1. Also, GWfoml/aTr is a constant and oW . |/8TS varies only slowly with T_ for a reasonable crew- compartment size. The relaxation lengths AY and Al can be chosen to be equal to some average values from the TSF data to within about +25% accuracy. Hence, in the first iteration, a reason- ably good estimate of { is obtained. Step b. Equation 17 divided by Eq. 16 and com- bined with the condition Er = ES gives a relation- ship between T, and T_ that involves appropri- ately averaged relaxation lengths and three basic parameters. One parameter involves the relative rate of shield weight change with respect fo the rear of the side shield thicknesses at the crew compartment. The second parameter is the ratio of the total air-scattered dose into the rear to that into the side of the crew compartment. The third parameter is closely related to the ratio of the total direct-beam dose at the rear to the total air- scattered dose at the side of the crew compartment. In detail, the relationship discussed above is obtained in the following manner. If Eq. 17 is divided by Eq. 16 and the definitions for AY and A given by Eq. 18 are used, there results N . E [sz,reur + (A;‘/I\dr)Di,rear] n=] ) S anofal (19) AS ——— [ o s T awtotul o + A'.S aTr r = Dtotul Xd ' (22) _ 'Cr 1 awtotol/aTs Aj‘- S L Mo/ T, e D el Xd (21) £ = — e’ 2 ) Aj (aWtofal/aTs) + )\: (aWtotcl/aTr) N z Ds,side n Lon=1 - (cos 6+ — cos §,+) t2ps. (6,) 1, S (cos §,+ — cos @, ) 42ps (6,) fi rear = (cosmfl en, - Co$m+l.6n,,) fdr , aWtofal/aTs F 5 aWtotcxl/aTr ;\— r 5 209 "ANP PROJECT PROGRESS REPORT !, and )\.f by ond defme new quonhhes AS, A f (V)ld)dz -j; T (1/AS)dx Z B, e e ‘ n=1 : R ' N 7_f " (1/A,)dt L 5,e n n=1 _ - —T //\S rT | T _j; ”(l/)td)dt -_]; ’(I/A;)dy _ N . o = E Cne e ! . S T - / r = (24) . T, )\s _ n=1 ' - o e - ‘N ..f " (/A )de - : 0 d , E ,Cne n=1] o -f (I/Ad)dt ..f (1/A7)dy ' (J, /Al ‘-T/\' E] oA : " (1/A )t - N _ L U,/Ap)e n=1 Equcmons 9, 10, cnd 12 are substituted into Eq. 22 and then, by using the defmmons given in Eqs. 23 and 24, Eq. 22 can be rewritten as .. [w ..fT” (17 )dt '[ - ,{.3—.. E Cn € 0 /‘———r— (25) — e-Ts/ S ik T/ s . | IZVJ . e-foT” (1/7A)dt n=] " N - " (1/A )t AL U, /ADe 0 fon ' -, )\; n=1 e T N -f n (l/hd)dt Y B,e 0 n=1 nfi‘ . * L " | (27) Equation 25 relates T, and T_ in terms of the various averaged relaxation lengths and the three pardmeters whose physical significances are dis- cussed above. The first parameter discussed above is the quantity a in Eq. 25. The second parame- ter is the left bracketed term at the right side of Eq. 25, and the third parameter is the right bracketed term. In a given iteration the parameters and averaged relaxation lengths are evaluated on the basis of the information obtained in the pre- vious iteration. In the first iteration, AS is taken to be the same constant as that used for )ts in Step a, etc. Also, for the first iteration, “the reactor shield is taken to be of an unspecified ' umform thickness (T = a constant for all »), in whuch case the bracke’red terms in Eq. 25 reduce to N __ N - ‘}"ZI Cn A; 2: ]n n=1 d n=1 a . N " __ N L B, r; LB, n=] n=1 Hence, in a given iteration, a plot can be made of T, vs T, which, upon convergence to the required solution, is the relation which T and T_ must satisfy in the vicinity of the solution to obtain equal values of L. For convenience, this relation- shlp is de5|gnated by (26) T, = Q(T) . between T_ and the various T,'s. [f use is made of Egs. 9, 10, and 12 and of the definitions given by - Eq.723 ‘then Eq. 15 can be rearranged as 'follows - P 2 —_I; " (1/A)dt d(“ ) e oMt PERIOD ENDING SEPTEMBER 10, 1955 In Eq. 27, Cn is set equal to L, as previously de- termined in Step a, Eq. 21. By using the values of A that are consistent with the results of the previous iteration, the right side of Eq. 27 is cal- culated for each n (n = 1, 2, ..., N) for various assigned values of T_. From a plot of the left side of Eq. 27 vs T, the values of T, correspond- ingto each assigned value of T _ are then obtained. Hence, plots can be made of T vs T _ for each n, Step d. For various assumed values of T, values of T are obtained from the plots made in Step c. These values are then inserted into Eq. 16, with use being made of Eq. 9 and the definitions given by Eg. 23 to compute the C for each T, A plot is then made of .,C vs T_. The value of T, for which the correSpondmg CS is equal to the value of L determined in Step a, Eq. 21, is the required T for. the given iteration. The corresponding values of the T and T ,’s, for the given iteration, are then obtained from the plots made in Steps b and ¢c. By using the above-described procedure, the various shield thicknesses T, T, and T, for n=1,2, ..., Nare determined in a given iteration. The entire procedure is repeated for the following iteration, and the iferations are continued until convergence is obtained, Application of TSF Data The following fundamental quantities must be known as functions of the pertinent variables involved in order to carry out the neutron shield optimization calculations: 1. the fast-neutron-dose air-scattering probabili- - ties, ©2PS. . (6) and 42P3,_ (6), feay Sfe'fi c. Relctlonshlpsare ‘also to be obtdi'néah 2. the reloxohon lengths A g A Al s and /\S 3. the focusing factor {$ and the geome'rrlcul atten- vation factors and /% T 5 _f (1 /)\i)dx B e "0 + Cn (T ) _f s (1/A])dy e 0 + ], e 0 21 e " ANP PROJECT PROGRESS REPORT 4, the angulur dlstrlbutlon of the fcst—neufron dose at the surface of the reactor primary shield. lnformcmon concermng these fundamental quanti- ties was obtained in Phase | of the TSF differ- enhcl shleldmg experlmenfs. However, there are some gaps that require extension of the ex:s’rmg data for the present calculations, In some cases, __Ilml'red but appropriate, data were available to "mdlcate a reasonqble means for extension. Also, the extension was “guided by qualitative theoretical considerations of ‘the attenuation processes in- volved. For some cases, no reliable extension of ~ the data was p0551ble, and these limitations in the '1i'use of ‘the data will be indicated. It should be ‘noted that the reqUIred data can be obtained by , furfher experlmenfs and dnclyses cn‘ the TSF of 2-0t~056~ 7 ~A—165 0.02 iwete) £2%p 0.005 0.002 0,001 — 0 30 60 90 120 150 180 8, CONICAL-SHELL BEAM ANGLE (deg) Fig. 142, P;‘ob'abamy'of Fast-Neutron Dose o Scaflermg from Comcal Shell Beam to Crew- o ‘Compurfment Side as Obtained from TSF Experi- ffl'_"“"?‘ (Tn =45 em, 1= 64 #). the attenuation processes involved. Plots of {2PS 4o(6) and £2ps Coarl0) as functions of 6 are given in Flgs. 14.2 and 14.3, respectively. ~ These plots apply for a reactor-to-crew-compartment separation distance, 1, of 64 ft and for sea-level altitude — the conditions of the experiments. At other separation distances and alh’fudes, it is necessary to apply corrections; corrections indi- cated by single air-scattering theory will probably be adequate for the present calculations, Rigor- ously, the air-scattering probabilities in Figs, 14.2 and 14.3 apply only for fast-neutrons filtered through 45 c¢m of water at the reactor shield, that is, for T, = 45 em. However, limited data obtained for T, =15 cm (for which the fast-neutron spectrum is expected to be quite different from that for T, = 45 cm) indicate that the effect of the spectrum 2-041-056 ~7T-A~467 0.5 Q.2 8) rear o4 P Q.05 0.02 Q.01 —— 0 30 60 20 120 150 180 ~ 8,CONICAL SHELL BEAM ANGLE (deg) ) Fig. 14.3. Probablhty of Fast Neutron Dose " Scattering from Conical-Shell Beam to Rear of Crew Compartment as Obtained from TSF Experl- ments (T = 45 cm, 1= 64 f1). e s i £ e * i W A v»x ' Ca i i ‘ 7.\, DIRECT- BEAM RELAXATION LENGTH. {cm) shift is relatively small. Hence, the air-scattering probabilities plotted in Figs. 14.2 and 14.3 were taken, in the present calculations, to be inde- pendent of the energy spectrum of the neutrons emanating from the reactor shield (that is, inde- pendent of T ). Also, values of *fiszea (6) were measured only in the range of angles, 6 = 90 to 180 deg, wherein the direct- beum dose at the rear of the simulated crew compartment was small com- pared with the air-scattered dose. The values of @Pfe (6) in Fig. 14.3 are extrapolated values in the range of angles from 0 to 90 deg, the extrapola- tion being guided by the variation of £2ps 6 measured for this range of angles. “The TSF measurements show that the relaxation length for the direct-beam fast-neutron dose is a function of the total water thickness between the reactor and the dose detector at the rear of the crew compartment; that is, the relaxation length is independenf of whether the water is at the reactor or at the rear of the crew compartment, A plot of the direct-beam relaxation length vs the total water thickness is given in Fig. 14.4, and from this plot the direct-beam relaxation length, A, ot any point in the reactor water shield can be obtained. In addition, this plot gives the direct- beam relaxation length A} at the water shield at 2-C1-056—-7-A428 O TSFDATA | '® BSF DATA CORRECTED FOR GEOMETRY 0 VN _4,50._ TOTAL WATER THICKNESS BETWEEN REACTOR FACE AND DETECTOR (Cm) for Fast-Neutron Dose. . Dose Scattered to the Crew-Compartment Side .Fig.. 14.4. Direct-Beam Relaxation Length ()t) PERIOD ENDING SEPTEMBER 10, 1955 the rear of the crew compartment for direct-beam radiation emanating from the nth conical shell of the reactor shield; the water thickness to be used in the plot is the shell thickness, T, plus the dis- tance in the water at the rear of fhe crew-compart- ment shield at which the relaxation length, A7, is desired. If plastic, instead of water, is used as the crew-compartment shielding material, the values of AJ taken from Fig. 14.4 should be divided by 1.14 (based on removal cross sections). In the TSF experiments, the scattered-dose re- laxation lengths, AS, at the side of the crew-com- partment shield were obtained as functions of water thickness at the side for various values of the angle 6. In these measurements, the fast neutrons were filtered through 45 e¢cm of water at the reactor, that is, T, = 45 cm. Plots of A3(45,x) vs x for various angles O are presented in Fig. 14.5, where A3(45,x) is the A measured at water thickness x into the side of the crew-compartment shield for fast neutrons filtered through 45 cm of water (T = 45 cm). For the neutron shield calcu- lations, it is necessary to know the variation of A, with reactor shield thickness, 7 . A limited amount of data obtained for T = 15 cm, when compared with the data for T = 45 em, indicates that A7 varies with T, in the same ratio as does the direct-beam relaxation length, A, This re- fationship is reasonable in view of the small 2-01-056-7-A-168 70 | g=0 MO 30 4% 6.0 g )\s {cm) i ] a0 W B » % © O % £ —— / / 50 4.0 — - 0 5 10 15 20 25 7, WATER THICKNESS AT SIDE OF CREW COMPARTMENT (cm) Fig. 14.5. Relaxation Length for Fast-Neutron Shneld from a Comcul Shell Beam as _a Function of Water Thlckness at the Crew-Compartment Side for Various Values of the Angle & (T £ = 64 ). = 45 cm, 213 ANP PROJECT PROGRESS REPORT neutron energy degradation that results from a neutron collision with air nuclei. The results of some dose measuremen’rs at the center of a crew- compartment mockup at = 90 deg further indicate the general validity of this relation. For a total neutron attenuation through the crew-compartment side shield of the order of ¢, the neutron attenua- tion calculated for Tn =15 cm, on the basis of the foregoing relationship, and the A2 values for T =45 cm checked with the measured attenuation to within 30%. Hence, the foregomg relationship, written in equcmon form, Lo A A.S(45 x) 7(28) Y (Tn,x) = ,—_,"d(_45—_3 AAT, + x) was used in 'rhe ccrlculaflons. In Eq. 28 )\S(Tn,x) is the AS at water depth x into the crew-compartment R Slde shleld for those fast neutrons emanating from the rec\cfor shleld comccl shell of thickness T _; AT, + x) is the Ad at total water thickness equal L to T+ x, The relaxation Iengths, Al for the air-scatfered dose at the crew-compar’rmenf rear shield were medsured for T ~of 6 from 90 to ]80 deg. The A values were es- senha”y constant over the mecsured range of 0 and T At the mid-point of the measured range of Tr which was approximately 15 cm, the A7 value was 7.0 ecm. It was assumed in the calcu- lations “that this Al value also applied in the range 6 = 0 to 90 deg In the same manner as described for A$, the effect of T on Al was ac- counted for by the relationship d(T + 15) S v T For plastic insrecd of water at the crew shield, both A% and A7 would be corrected in the same manner as described for )\é. An important limitation exists, however, in the use of the air-scattering probabilities and relaxation lengths p'r'esenfed here. In the TSF experiments, ' scofiered -dose measurements were not taken for - TS or T, smaller than about 5 cm of water. Hence, “fo obtain the dose for T orT, less than 5 cm, the data were extrapolated to TS =0orT, =0. The values of {ZPS (6) and *fizPs (8) as well 'ff‘,;_,f’_.?as the re]axahon lengfhs )\S qnd )\’ for T, or = 45 em over a range of values T, less than 5 cm are, hence, extrapolated values. For T_ and T, greater than 5 cm, the use of the plots, of course, leads to correct results (within ~the limitations previously discussed). However, for T, ‘and T, less than 5 cm, the plots are only as rellable as the extrapolation. Indications are that for T_or T less than 5 c¢m, the relaxation fengths AS and A7 change appreciably; hence it does not appear advisable to use the plots for crew shield thicknesses less than 5 ecm of water. The concept of the focusmg factor f; and the method of interpretation of the TSF experiments to obtain an experimental value of f were dis- cussed previously by J. E. Van Hoom:ssen.3 Van Hoomissen obtained an average value of < of 5.3 over the range of angle 0 f-rom 0 to 180 deg, " the variation of fs with 6 was small and well within the stchshcal accuracy of the data. Com- parison with the analytical results of Faulkner? indicates that the angular distribution of the dose at the inside surface of the crew-compartment side shield is approximately cos®. In the TSF experi- ments from which the value of /° of 5.3 was ob- tained, the side shield thickness for the crew- compartment mockup was about 38 cm of water. Inasmuch as the angular distribution of the dose at the inside surface of the crew-compartment sides would be expected to vary with side shield thickness, the focusing factor /7 is also expected to vary “With side shield thickness; however, Faulkner's results show that /% is not very sen- sitive to angular distribution (/3 is 4.0 for cos distribution and 6.5 for cos® distribution), In the calculations, % was taken to be constant at 5.3. This value of /7 should be well within 25% of the correct value, at least for side shield thick- nesses greater than about two relaxation lengths wherein the extremely slanted neutrons are atten- uated. To obtain the geometrical attenuation focfors " . _ fI and f], the angular distribution of dose at the inside surfoce of the crew-compqrtment rear shield was taken to be cos® for the scattered dose and cos® for the direct-beam dose. Integration over the inside surface of the crew-compartment cirs cular rear shield for ’rhe dose at the center of \‘he 3.]. E. Van Hoomissen, ANP Quar, Prog. Rep. June 10, 1955, ORNL-1896, p 217. 4). E. Faulkner, Focusing of Radiation in a Cylin- drical Crew Compartment, ORNL CF-54-8-100 {Aug. 18, 1954). ot AR e # -y, " ¥ : cn‘ ‘a distance of 64 ft from the reactor as a func. " s.&of the water shleid cn‘ theflj o cylindrical crew compartment (length of cylinder assumed to be equal to diameter) gives fI = 0.35 and 7 = 0.50. _ The angular distribution of the fosf-neutron dose emanating from the reactor primary shield surface was taken, in ~ v & : \\.,___ y=100cm / g S —— » N o D - g < g & \ ! - F b =195 ft 2 d = 64 ft ; CENTER OF SCINTILLATION CRYSTAL AT: ' " x = VARIABLE " y'="AS NOTED 2=0 ------- . ‘0—7 —— — - - —_— N .40 S300 =p0 o 0 Ti00 20 30 40 x, HORIZONTAL DléTANCE FROM ¢ AXIS TO DETECTOR CENTER (em) Fig. 14.11. Gamma-Ray Dose Rates Along x Axis of Crew Compartment (y = 100, 130, 150, and 160 cm; z = 0). - 46 2-01-056-3-70-154A 10'6 ’ l ’ I \ } r ‘ l 107 , , ‘ ALL CURVES TAKEN WITH REACTOR . ALL CURVES TAKEN WITH SHIELD COMPARTMENT D FILLED © REACTCR SHIELD COMPARTMENT D WITH WATER - p—- FILLED WITH WATER — T = e, P T L e T . - L ",’_ _,_.—-‘_--_ -—..A,___bh 3 T | e s é/“" T ri— \‘ S g ',/'\ . 3z 5 71~ T~ 5 7 y =155 em ] : 1 N S ~ £ E — - . b e E u \ W E ¥y =125 e¢m = @ L W w -9 @ h =195 ft - _ 8 d= 64 ft ~ =100 cm Y ‘ % T~ \\>/ % CENTER OF SCINTILLATION CRYSTAL AT CF —— e x X = VARIABLE < < o y=198.8cm = 2 52 ; h =195 ft £ e y=230cm g d =864 ft 3 A y=1489 cm _ A y=17 CENTER OF SCINTILLATION s =170 cm CRYSTAL AT: z=0 x = VARIABLE ¥ = AS NOTED Z=0 - ’ ‘ g’ 1077 ~40 =30 20 -0 0 10 20 30 40 -4Q0 =30 -20 -0 0 10 20 30 40 x, HORIZONTAL DISTANGE FROM o AXIS TO DETECTOR CENTER {cm) Fig. 14.10. Gamma-Ray Dose Rates Along x Axis of Crew Compartment (y = 170, 189, 198.8, and 219 Jois. i e e PrARRR TS i i s i et 3 iy ik A BRI BB i s y: il b, e il e . i e S i i o e e . i dara iy il A i e oo, d ) A e L ~ Aol ik i i —y . —— i e ; - i i " OFFICIAL USE ONLY AIRCRAFT REACTOR ENGINEERlNG DIVISION THE OAK RIDGE NATIONAL LABORATORY SEPTEMBER 1, 1955 §. J. CROMER, DIRECTOR H. MCFATRIDGE, SEC. RD ARE ASSISTANT TO DIRECTOR R. § CARLSMITH ARE R. E. THOMPSON ARE REACTOR PHYSICS REACTOR CONSTRUCTION POWER PLANT ENGINEERING EXPERIMENTAL ENGINEERING ENGINEERING DESIGN 7503 AREA CONSTRUCTION A, M. PERRY ENR E.’S. BETTIS ARE A. P. FRAAS ARE H. W. SAVAGE ARE H. C. GRAY PWA . G. PIPE ARE M. WILSON, SEC. ARE M. OVERTON ARE P. HARMAN, SEC. ARE D. ALEXANDER, SEC. ARE J. ZASLER ARE S, M. JANSCH SEC. ARE L. E. FERGUSON, SEC. ARE H. W. BERTMNI ARE FLUIE MECHANECS AND ART ADMINISTRATION R. CORDOVA ARE A, FORBES ARE REACTOR DESIGN V. 5. KELLEGHAN ARE W. E. KINNEY ARE G.D. WHITHAN ARE W. L. SCOTT ARE J. 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L. SNAPP PWA J. L. CROWLEY ARE e ey e INSTRUMENTATION AND CONTROLS B.L. GREENSTREET ARE 3. J. SIMON PWA W. H. KELLEY ARE o werLe s B WARD ARE W, J. MUENZER ARE L soN e : E. R. MANN Ic W. 1. CALYON, DRAFTSMAN ARE H. C. YOUNG PWA H. C. SANDERSON PWA V. G GEORGE ARE R.G. AFFEL IC ’ CORROSION LOOPS ‘ M. C. BECKER P HEAT TRANSEER HEAT EXCHANGERS AND 5 G. H, BERGER IC SPECIAL EQUIPMENT C. P, COUGHLEN ARE ELECTRICAL DESIGN J. M, EASTMAN B R. D. SCHULTHEISS ARE R. E. MACPHERSCN ARE R. A. DREISBACH PWA T. L. HUD! ARE C. F, HOLLOWAY Ic é TOSRAs QSE J. C. AMOS ARE P. G. SMITH ARE A.H. ANDERSON ARE R, F. HYLAND iIc M. H. COOPER PWaA J. KERR ARE 1. W, KREWSON Ic H. C. HOPKINS PWA L. H. DEVLIN PWA ELECTRIC SERVICES B.C. GARRETT PWA W. R, MILLER* Ic H. WIARD cv L. R. ENSTICE PWA E. M. LEES ARE J. 0. NICHOLSON * ARE S. C. SHUFQRD PWA M. M. YAROSH ARE F. FERRIGNO PWA D. L. CLARK ARE C. B. THOMPSON MH 1. W. KINGSLEY ARE W. F. FERGUSON- ARE GENERAL DESIGN E. YINCENS IC SPECIAL PROBLEMS R. D. PEAK PWA C. E. MURPHY ARE C. 5. WALKER Ic A. L. SOUTHERN ARE A. A ABBATIELLO ARE G. €. GUERRANT Ic ¥ 2 COTTRELL fne J. G. TURNER PWA TEST OPERATIONS J. M. CORNWELL PWA C' s' BURTNETTE USAF J. 4 MILICH PWA H. J. KICKINSON PWA -3 E. F. JURGIELEWICZ PWA C. J. PRICE USAF PROCUREMENT COORDINATION TECHNICIAN GROUP 3T, MEADOR PWA W. F. BOUDREAU ARE R. HELTON ARE W. A, SYLVESTER PWA CONSULTANTS J. PARKER, 3EC. ARE J. S. ADDISON ARE N. E. WHITNEY PWA T. ARNWINE ARE G. R. HICKS ARE A. H. FOX, UNION COLLEGE GENERAL EQUIPMENT 6. 5. CHILTON ARE C. A, MILLS ARE W. LOWEN, UNION COLLEGE W. R. OSBORN ARE J. M. COBURN ARE C. F. SALES ARE R. L. MAXWELL, UNIVERSITY OF F. M. LEWIS ARE J. R. CROLEY ARE TENNESSEE s g-g\-MS\LSREY QEE W, CLFNN!NGHAM ARE CHECKING G. F. WISLICENUS, PENNSYLVANIA STATE - ¥ R. E. DIAL ARE : COLLEGE D. L. GRAY ARE LR DUCKWORTH ARE J.R. LARRABEE PWA $_ flAsxsgg igg W. H. DUCKWORTH ARE G. G, MICHELSON ARE H. W. K. R, FINNELL ARE $.R. ASHTON ARE H. FOUST ARE RECGRDS AND PRINTING C. A, CULPEPPER ARE ¥. D. GHORMLEY ARE s, J, FOSTER ARE . G. C. JENKINS ARE C. J. GREEN ARE 3. 1 PLATZ ARE : E. 8. PERRIN ARE T. L. GREGORY ARE F. M. GRIZZELL ARE WELDED EQUIPMENT R A HAMRICK ARE R. B. CLARKE ARE P. P, HAYDON ARE B. E. BLACK ARE C. G. HENLEY ARE E. B. EDWARDS ARE B. L. JOHNSON ARE H. ¥. HOOVER ARE J.R. LOVE ARE E. A. JAGGERS ARE D.E. MCCARTY ARE T. A. KING ARE G. E. MILLS ARE J. W. TEAGUE ARE B. H. MONTGOMERY ARE C. C. NANCE ARE SPECIAL EQUIPMENT 3 T PARSONS ARE W. D. GOOCH ARE H. E. PENLAND ARE L. W.LOVE PWA M. A. REDDEN ARE T. K. WALTERS ARE R. REID ARE D, R, WESTFALL ARE F. J. SCHAFER ARE J. R. SHUGART ARE IN-PILE LOOP TESTS €. E. STEVENSON ARE D. B. TRAUGER ARE A. G. TOWNS ARE C. A, WALLACE ARE 5. EUBANKS, SEC. ARE B C WILLIAMS ARE C. C.BOLTA PWA - L.'P. CARPENTER ARE J. A, CONLIN ARE C. W, CUNNINGHAM ARE CONSULTANTS ot AT o J. F. BAILEY, UNIVERSITY OF TENNESSEE i R. L. MAXWELL, UNIVERSITY OF TENNESSEE OFFICE SERVICES W. K. STAIR, UNIVERSITY OF TENNESSEE J. P, LANE ARE T AT TR 221 e i OFFICIAL USE ONLY i THE AIRCRAFT NUCLEAR PROP;ULSION PROJECT AT ., THE OAK RIDGE NATIONAL Lfl)‘BORATORY SEPTEMBER 1, 1955 i SUPPORTING RESEARCH W, H, JORDAN A, 3, MILLER i % STAFF ASSISTANT STAFF ASSISTANT STAFF ASSISTANT STAFF ASSISTANT STAFF ASSISTANT STAFF ASSISTANT W. K. ERGEN ARE E. P. BLIZARD AP W. R. GRIMES MC W. D. MANLY M D. 5. BILLINGTON s H. F. POPPENDIEK REE REACTOR PHYSICS SHIELDING CHEMISTRY ANALYTICAL CHEMISTRY |METALLURGY METALLOGRAPHY RADIATION DAMAGE HEAT TRANSEER AND PHYSICAL 1 PROPERTIES RESEARCH A. SIMON* AP W, R. GRIMES MC M. T. KELLEY* AC W. D. MANLY | M R. ). GRAY* M D. 5. BILLINGTON* 5 SHIELDING RESEARCH D. R. CUNEO NC C. D. SUSANO* AC W. H. BRIDGES* M M. J. FELDMAN I3 H. F. POPPENDIEK REE D. E. CALDWELL, SEC. MC 8. E. YOUNG,* SEC. AC J. THOMAS, SEC. M G. W. KEILHOLTZ s T. K. CARLSMITH, SEC. REE C. L. BRADSHAW" MP E. P. BLIZARD* AP J. C. WHITE AC R. 5. CROUSE M J. B. TRICE 5 R. R. COVEYOU* AP R. RICKMAN, SEC. AP E. M. ZARZECKL,* SEC. AC T. M. KEGLEY M J. €. WILSON ss L. DRESNER* AP $. AUSLENDER PWA SPECIAL PROBLEMS GEMERAL CORROSION D. F. STONEBURNER M HEAT TRANSFER M. D. GIVEN* MP M. E. LAVERNE AP ] E.R. BOYD M 1. H. MARABLE* AP £. H. MURRAY AP R. F. NEWTON RD E. E. HOFEMAN M B. F. DAY M MTR LIAISON C. M. COPENHAVER REE RESEARCH M. L. NELSON* AP R, B. MURRAY AP R. CARLANDER PWA B J REECE " N. D. GREENE REE PHASE EQUILIBRIUM STUDIES A.S. MEYER, JR. AC W. H. COOK " H. V. KLAUS 5 H. W. HOFFMAN REE SHIELD DESIGN G. GOLDBERG AC D. H. JANSEN M F. €, LYNCH REE CONSULTANT ¢ i ':AA%L?\?jrCHER fi B. L. MCDOWELL AC J. E. POPE M HOT LAB FACILITY G. L. MULLER PWA J. B, DEE PWA e W. J. ROSS AC L. R, TROTTER M L. D. PALMER REE J. A. NOHEL, GEORGIA TECH. B. H. CLAMPITT MC -d: : M. J. FELDMAN 55 C. A, GOETZ PWA H. DAVIS PWA C. R. WILLIAMS AC : ELLIS J. L. WANTLAND REE K. PENNY AP - DYNAMIC CORROSION C. 55 R. M. BURNETT REE J, SMOLEN PWA R. E. MINTURN USAF CERAMIC RESEARCH E. J. MANTHOS 58 . DEVELOPMENT J. LONES REE D. K. TRUBEY AP R. E. MOORE e J. H. DeVvAl M . . B. PARSLEY 55 R. L. MILLER REE M€, WOODSUM PWA R. J. SHEIL MC 1. P. YOUNG AC E. A, KOVACEVICH M J. M. WARDE® M R. N. RAMSEY 55 G . WINN REE D. ZUCKER M M. A, MARLER AC A. TOBCADA M A, HOBBS,* SEC. M E. 5. SCHWARTZ s5 ’ CRITICAL EXPERIMENTS LID TANK SHIELDING FA G. D, BRADY M 1L CILITY PHYSICAL CHEMISTRY SERVICE k. W, EVANS " RADIATION METALLURGY A. D. CALLIHAN® AP R. W. PEELLE AP ‘ C. E. CURTIS* " . PHYSICAL PROPERTIES M. L. RUEFF,* SEC., AP G. T, CHAPMAN AP F. F. BLANKENSHIP MC W. F. VAUGHN AC FABRICATION J. R, JOHNSON* M J. C. WILSON 5 5.1, COHEN REE W, J. McCOOL, PWA M. BLANDER MC R.F. APPLE ) AC [ A J. TAYLOR* M C. D. BAUMANN S5 v b oeRs REE 3. M. MILLER AP S. CANTOR MC D. E. CARPENTER AC J. K, COOR M 1. A, GRIFFIN® M W. E. BRUNDAGE s5 . G‘ C. BLALOCK REE J. 5. CRUDELE PWA E. BECKHAM AP R. E. CLEARY PWA R. C. BRYANT AC M. R. D"AMORE PWA W, W, DAVY(S sS S.J ‘CLAIBORNE REE T ELLIS AP 3 FRANCIS AP H. A, FRIEDMAN MC L. R, HALL AC H. INOUYE M N. E. HINKLE s 4 Sones REE W. J. FADER PWA H. JARYS I S, LANGER MC L. E. IDOM AC J. P. PAGE M CONSULTANTS A. 5. OLSON S5 - V. 6. HARNESS* AP J.R. TAYLOR AP R. P. METCALF MC A. H. MATTHEWS AC T. K. ROCHE M R. A. WEEKS* 8§ J. 1 LYNN AP . W, WAMPLER AP R.E. THOMA MC C. E. PRATHER AC R. W. JOHNSON M G. M, BUTLER, CARBORUNDUM COMPANY 1, C. ZUKAS 55 E. R. ROKRER* AP A D WILSON ac !D M. T. CORY, GRAPHITE SPECIALTIES T. PRICE PWA E. V. SANDIN PWA FUEL PREPARATION RESEARCH C. M. WILSON AC WELDING AND BRAZING CORPORATION D. SCOTT, JR. ARE BULK SHIELDING FACILITY ! H. INSLEY RADIATION CHEMISTRY 5. SNYDER PWA F. €. MAIENSCHEIN AP G. M. WATSON st P. PATRIACA M T. N, MGVAY, UNIVERSITY OF ALABAMA FUEL REPROCESSING R, M. SPENCER USAF C. BOUNDS, SEC. AP C. M. BLCOD MC R. E. CUAUSING ] 7. 5. SHEYLIN, OHIO STATE UMIVERSITY G. W. KEILHOLTZ 58 . D. V. P, WILLIAMS* AP T.V. BLOSSER AP F. L. DALEY MC R.L.H ‘ESTAND Pwa H. THURNAUER, MINNESOTA MINING AND W. E. BROWNING 58 F. R, BRUCE cT ¢ D-ZERBY* AP G. M. ESTABROOK AP F. W. MILES . MC G. M. SLAUGHTER M MANUFACTURING COMPANY D. E. GUSS USAF e LD FLYNN AP G. E.{CONNOR M H. L. HEMPHILL $5 A T. FUTTERER PWA CORROSION STUDIES SPECTROGRAPHIC ANALYSIS B. McDOWELL M M. F. OSBORNE 35 CHEMICAL DEYELOPMENT M. P. HAYDON AP L . C. E. SHUBERT M H. E. ROBERTSON 55 - F. KERTESZ MC 4. R MCNALLY st D. E. FERGUSON* cT K. M. HENRY AP B ORRIS* AND OTHERS by R. G, SHOOSTER M M. T. ROBINSON 55 £ B, JOHNSON AP H. J. BUTTRAM MC - A. NORR L. C. WILLIAMS M C. C. WEBSTER 55 G. I. CATHERS cT T. A LOVE AP F. A, KNOX MC METALLURGY CONSULTANTS W. R. WILLIS 55 M. R. BENNETT CT W 20BEL 5 R. E. MEADOWS MC PHYSICAL CHEMISTRY OF LIQUID METALS R. M. DUFF cr " D. J. KIRBY AP G. F. SCHENCK PWA ! N. CABRERA, UNIVERSITY OF VIRGINIA FLUX MEASUREMENTS J. SELLERS iC J. M. DIDLAKE MC G. P. SHITH M N. J. GRANT, MASSACHUSETTS UNIT OPERATIONS R. M. SIMMONS AP €. R. BCGSTON " INSTITUTE OF TECHNOLOGY A B TRICE 5 W, K. EISTER* cT D, SHIDDIE \c PRODUCT{ON OF PURIFIED FUELS MASS SPECTROMETRY J. V. CATHCART M J. L. GREGG, CORNELL UNIVERSITY J. KRAUSE PWA )T, LONG cr F L] . H, W. LEAVENWORTH PWA W. D, JORDAN, UNIVERSITY OF ALABAMA M STAINKER &1 . G. $TOUT ic G. J. NESSLE MC C. R. BALDOCK S| G. F. PETERSEN M E.F. NIPPES, RENSSELAER ENGINEERING PROPERTIES 5. H.S H. WEAVER AP 3. P, BLAKELY MC ) R.SITES si . G, JONES, JR. cr M. E. STEIDLITZ M POLYTECHNIC INSTITUTE 0. SISMAN® WA €. R, CROFT MC R. W.ANDERSON M W. F. SAVAGE, RENSSELAER - 58 4. 5 WATSON T TOWER SHIELDING FACILITY F. A. DOSS MC L : R. M. CARROLL 55 J. E. EORGAN L L'FA - M POLYTECHNIC INSTITUTE J. G. MORGAN 55 DESIGR C. E. CLIFFORD AP N, V. SMITH i l G. SISTARE, HANDY & HARMON M. T. MORGAN 5 E. McBEE, SEC. AP ) TROITT s MECHANICAL PROPERTIES P. C. SHARRAH, UNIVERSITY OF H. E. GOELLER* CcT J. L. HULL AF ¥. 7. WARD MC D. A. DOUGLAS M ARKANSAS R. P. MILFORD cT F. L. KELLER AP . R. K. BAGWELL MC C. R, KENNEDY PWA F. G. TATNALL, BALDWIN-LIMA-HAMILTON F. N. BROWDER cT F. W. SANDERS AP J‘ P ’ EUBANKS MC J : RI'WE R IR M E. C. WRIGHT, UNIVERSITY OF ALABAMA N BAC B, F. HITCK MC J. W. WODDS M PILOT PLANT D RSROLL « W, JENNINGS MC K. W. BOLING W H. K. JACKSON™ eT -D. G. A. PALMER MC 4. T. GAST M W. H. CARR* T 1. D. CONNER AP B. C. THOMAS MC 4. B, HUDSON M * J.N. HONEY AP ‘ W. H. LEWIS cT - M R. G. WILEY MC V. G. LANE M G. G. UNDERWOOD ic B. MchABB, JR. M METALLURGY CONTRACTORS R. E. WRIGHT AP CHEMICAL EQUILIBRIA g- g TL%‘:‘;%S' IR. ’; BATTELLE MEMORIAL INSTITUTE . K. BRUSH BERYLLIUM COMPANY L. G. OYERHOLSER NC C. W, YIALKER M FERROTHERM CONSULTANT E. E. KETCHEN MC M B. PANISH He | GLENN L. MARTIN COMPANY H. A.-BETHE, CORNELL UNIVERSITY Vb REDMAN e NONDESTRUCTIVE TESTING METAL HYDRIDES, INC. D NEW ENGLAND MATERIALS TESTING i B. J. STURM M R. B. OLIVER M LABORATORY . L. E. TOPOL. MC J. W, ALLE M CONTRACTORS ‘ R W. MeCLUNG “ RENSSELAER POLYTECHNIC INSTITUTE METAL HYDRIDES, INC. SUPPORTING STUDIES K. W. REBER M fj:f’\fg;gmuoaf 'F&anéshslze NUCLEAR DEVELOPMENT ASSOCIATES, : W, J. HASON W P. A. AGRON c | J. E. SUTHERLAND < CONSULTANTS H. INSLEY T. N. MCVAY, UNIVERSITY OF ALABAMA ! CONTRACTORS 5 AMES LABORATORY , BATTELLE MEMORIAL INSTITUTE ! CARTER LABORATORIES f MOUND LABORATORY | A. R. NICHOLS, SAN DIEGO STATE : COLLEGE UNIVERSITY OF ARKANSAS *PART TIME 222 i e, < - g i . i oncill ik ol e oy i i 055, Gk sein. A s i R OFFICIAL USE ONLY THE AIRCRAFT NUCLEAR PROPULSION PROJECT AT THE OAK RIDGE NATIONAL LABORATORY SEPTEMBER 1, 1355 ANP PROJECT DIRECTOR W. H. JORDAN RD CO-DIRECTOR S. J. CROMER RD ASSISTANT DIRECTOR A. J. MILLER RD D. HILYER, SEC. RD PRATT & WHITNEY AIRCRAFT REPORTS E. R. DYTKO, ASST. PROJ. ENG. PWA . A. W, SAVOLAINEN ARE A. GIANGREGORIO, ADM. ASST. PWA 0. A, LIVINGSTON, SEC. ARE LITERATURE SEARCHES H. C. GRAY, DESIGN ENGINEER PWA : A. L. DAVIS ARE S. J. CROMER, DIRECTOR H. McFATRIDGE, SEC. AIRCRAFT REACTOR ENGINEERING DIVISION RD ARE ANP STEERING COMMITTEE W. H. JORDAN, CHAIRMAN E. 5. BETTIS D. 5. BILLINGTON E. P. BLIZARD G. E. BOYD S. J. CROMER ASSISTANT TO DIRECTOR R. S, CARLSMITH . ERGEN . FRAAS . GRIMES ARE . LARSON EXPERIMENTAL ENGINEERING H. W. SAVAGE ARE POWER PLANT ENGINEERING A. P, FRAAS ARE ENGINEERING DESIGN H. C. GRAY PWA REACTOR CONSTRUCTION E.S.BETTIS ARE REACTOR PHYSICS A. M. PERRY ENR 7503 AREA CONSTRUCTION W. G. PIPER ARE . MANLY . MILLER . POPPENDIEK . SAVAGE . SHIPLEY . SWARTOUT . WEINBERG PrmITI>EAErE TPUET-OMBTOX NOTE: THIS CHART SHOWS ONLY THE LINES OF TECHNICAL COORDINATICN OF THE ANP PROJECT, THE VARIOUS INDIVIDUALS AND GROUPS OF PEOPLE LISTED IN THIS AND THE FOLLOWING CHARTS ARE EN- GAGED EITHER WHOLLY OR PART TIME ON RESEARCH AND DESIGN WHICH IS COORDINATED FOR THE BENEFIT OF THE ANP PROJECT IN THE MANNER INDICATED ON THE CHART. EACH GROUP, HOWEVER, - 1S ALSO RESPONSIBLE TO ITS DIVISION DIRECTOR FOR THE DETAILED PROGRESS OF THE RESEARCH - AND FOR ADMINISTRATIVE MATTERS. ' L THE KEY TO THE ABBREVIATIONS USED IS GIVEN BELOW. AC ANALYTICAL CHEMISTRY DIVISION —ORNL AP APPLIED NUCLEAR PHYSICS DIVISION — ORNL ARE AIRCRAFT REACTOR ENGINEERING DIVISION — ORNL BAC BOEING AIRPLANE COMPANY BP BENDIX PRODUCTS, DIVISION OF BENDIX AVIATION CORPORATION C CHEMISTRY DIVISION ~ ORNL CT CHEMICAL TECHNOLOGY DIVISION - ORNL CY CONSOLIDATED VUL TEE AIRCRAFT CORPORATION ENR ELECTRONUCLEAR RESEARCH DIVISION — ORNL tC INSTRUMENTATION AND CONTROLS DIVISION ~ ORNL M METALLURGY DIVISION ~ ORNL MC MATERIALS CHEMISTRY DIVISION ~ ORNL MH MINNEAPOLIS-HONEYWELL REGULATOR COMPANY MP MATHEMATICS PANEL — ORNL PWA PRATT & WHITNEY AIRCRAFT, DIVISION OF UAC RD RESEARCH DIRECTOR’S DEPARTMENT — ORNL REE REACTOR EXPERIMENTAL ENGINEERING DIVISION ~ ORNL St STABLE 1SOTOPE RESEARCH AND PRODUCTION DIVISION — ORNL $s SOLID STATE DIVISION ~ ORNL USAF UNITED STATES AIR FORCE *PART TIME - - SUPPORTING RESEARCH W. H. JORDAN A. J. MILLER METALLURGY _ W. D. MANLY, STAFF ASSISTANT M CHEMISTRY - W. R. GRIMES, STAFF ASSISTANT MC . SHIELDING : E. P. BLIZARD, STAFF ASSISTANT ' AP RADIATION DAMAGE D. 5. BILLINGTON, STAFF ASSISTANT . | W HEAT TRANSFER AND PHYSICAL PROPERTIES H. F. POPPENDIEK, STAFF ASSISTANT '~ REE REACTOR PHYSICS W. K. ERGEN, STAFF ASSISTANT ARE FUEL REPROCESSING F. R. BRUCE* c1 T Pt TR T Y TN TR 223 - LA L . ; . " L L [ 1 : C s v . Nl . ; ; § ; Vi 1 . Coe { : L L . v i . ; ) ‘. . Lo . ' . . i . : o Ll . . e . . e e