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4CAPSULE RECOVERY AND DISASSEMBLYThe transfer of the two capsule basket assemblies and the neutrondosimeter monitor assembly from the vessel to the spent fuel pool was handledby reactor personnel prior to arrival of the BCL shipping cask and BCLpersonnel at the reactor site.The s6ipping cask was positioned alongsidethe pool, the lid was removed, and the cask was lowered into the pool.Thethree assemblies were then transferred into the cask using an overhead crane.The cask was then moved from the pool and placed at the side of the pool.The cask lid was then reinstalled, and the exterior of the cask was decontaminated by Dresden personnel.After decontamination, the cask surface was2below the maximum allowable shipping limits of 2200 disintegrations/100 cm /2. min !3Y and 220/disintegrations/100 cm /min a. The cask was then shipped tothe BCL hot laboratory facility by commercial carrier.Upon arrival at BCL, the three ·assemblies were removed from the · cask and transferred to a hot c ell for visual examination and disassembly · Visual examination showed no unusual features or damage. ·Figure 1 shows aneutron dosimeter monitor assembly and two capsule basket assemblies similarto those from D3 (the assemblies shown are from QC 1).revealed no damage or unusual features.the identification "112C2381G-2".identification "112C 2381G-3".Visual examinationCapsule Basket Assembly No. 13 hadCapsule Basket Assembly No. 14 had theThe monitor assembly had the serial numberidentification "6509450".The two capsule basket assemblies were cut apart using a flexiblewheel attached .to a Mo to tool.Capsule Basket Assembly No. 13 contained twoCharpy capsules and three tensilecapsules The identification numbers ofthese five capsules are as follows, with the first being located closest tpthe identification number end and the last being located furthest from theidentification number end of the capstile basket as embly:. .

Cl653FIGURE 1 . TYPICAL CAPSULE BASKET ASSEMBLIES (LEFT AND RIGHT)AND NEUTRON DOSIMETER MONITOR ASSEMBLY (TOP MIDDLE)

6 Tensile Capsule G6Tensile Capsule G8Tensile Capsule GlOCharpy Capsule 117C3728Gl0Charpy Capsule 117C3728GllEach of the Charpy capsules contained an iron, a nickel, and a copperdo.s ime te r wire.Capsule Basket Assembly No. 14 contained four Charpy capsules andfive tensile capsules.The identification numbers of these capsules are asfollows, with the first being located closest to the identification numberend and the last being located furthest from the identification number endof the capsule basket assembly.Tensile Capsule G6Tensile Capsule G7Tensile Capsule GBCharpy Capsule 117C3728Gl4Tensile C5psule G9 Tensile Capsule GlOCharpy Capsule 117C3728Gl5Charpy Capsule 117C3728Gl6Charpy Capsule 117C3728Gl7Each of the Charpy capsules contained an iron, a nickel, and a copperdosimeter wire.A photograph ofin Figure 2.specimen.atypical Charpy capsule with a specimen is presentedFigure 3 shows a typical tensile capsule with a single tensile)Charpy capsules contain up to 12 specimens per capsule.Tensilecapsules contain 2 specimens per capsule.Charpy and tensile capsules were cut apa,rt using the same techniqueand equipment ·as used for the capsule basket assemblies.An inventory ofspecimens is listed in Table 1 for Capsule Basket Assembly No. 13 and inTable 2 for Capsule Basket Assembly No. 14.(a)The neutron dosiraeter flux monitor was cut apart to obtain the sixenclosed flux wires, Three of these were copper, and the other three were iron (a) In later sections of this report capsule basket assembly No. 13 andcapsule basket assembly No. 14 are referred to as "capsule G2" and"capsule G3", respectively.

7 CH 81 FIGURE 2.TYPICAL CHARPY CAPSULE WITH CHARPY SPECIMEN . ., -· .-,C1680FIGURE 3.TYPICAL TENSILE CAPSULE WITH TENS ILE SPECIMEN

. 8TABLE 1.INVENTORY OF SPECIMENS RENOVED FRON CHARPY AND TENSILECAPSULES FROM CAPSULE BASKET ASSEMBLY NO. 13Charpy Capsule KLBKCJKATKCSKB2KCLKBUKCNKB4Tensile Capsule G6. GSGlOLDALJ6LLSLD3LJMLLl

9 TABLE 2.INVENTORY OF SPECIMENS REMOVED FROM CHARPY ANDTENSILE CAPSULES FROM CAPSULE BASKET ASSEMBLY NO. 14Charpy Capsule nsile Capsule G6G7G8G9GlOLDELPLLJ2LUCLLDLDDLPSLJULU3LLT

, 10 SPECillEN PREPARATIONThe base material of the reactor pressure vessel isSA 302Grade B.Mechanical property specimens were prepared from actual vessel plate inaccordance with GE specifications.(S)slabsAll specimens were made from flattaken parallel to the plate surfaces and at the 1/4 plate thickness.Base metal Charpy and tensile specimens were machined with their longitudinal axes parallel to the plate rolling direction.notches were cutpe pendicularCharpy specimento the plate surfaces.The weld HAZ Charpy specimens were machined with the longitudinalaxis transverse to the weld length and parallel to the plate surface.axis of the notch is perpendicular to the plate surface.TheThe notch radiusis at the·intersection of the base metal and the weld metal.T e.Charpyimpact specimen design-is shown in Figure 4.standard specimen design recommended in ASTM Standard E23-72.specimen design is shown in Figure 5. It is theThe tensileIt has a nominal 0.250 in. gagediameter and a nominal 1.00 in. gage length

11 .1. c.001. :t .001I .: c- I. .315. jDETAIL 8lA .001( 11IA 1.00163I.394 :t.001FIGURE 4. CHARPY V-NOTCH IMPACT SPECIMEN.4375-14 UNC-2A-letl A oosR@ lBOTH Et'IDS .o. .062 PLACESI. .,NOTES. .- .001I. 0 .250DIA. AT CENTER OF REDUCED. SECTION. o':ACTUAL D DIA .002TO .005 AT ENDS OF REDUCED SECTION TAPERING TO D AT CENTER 2. GR/NO REDUCED SECTION 8 RADII TO 32/ RADII TO BE TANGENT TO REDUCEDSECTION WITH NO CIRCULAR TOOL MARKS AT POINT OF TANGENCY Ol? WITHINREDUCED SECTION. POINT OF TANGENCY SHALL NOT LIE WITHIN REDUCEDSECTION.FIGURE 5.TENSILE SPECIMEN

12 EXPERIHENTAL PROCEDURESThis section describes the procedures used in the determinationof neutron exposure and the impact, hardness, and tensile properties.Alltesting and evaluations were performed at Battelle's Columbus Laboratories.Original data is recorded in BCL Laboratory Record Books 31226 .and 31231.Neutron DosimetryNeutron dosimeter wires were located in the neutron dosimetermonitor capsule and in each of the two capsule basket assemblies.Theneutron dosimeter monitor capsule contained three iron and three copperwires.Each Charpy capsule in the two capsule basket assemblies contained one iron, one copper, and one Ni-Co wire.(11,12,13)As TM stan d ar d s are as f o 11 ows:The reactions and the associatedAS'IM StandardIronReaction5454.Fe(n,p) MnNickelsaN.i. n,p )sac oE264-70Copper6360· Cu(n,a) CoE523-74MaterialE263-70After removal from their containers, the wires were identified, placed intoindividual vials, and transferred to the radiochemistry laboratory.Theywere then cleaned by wiping using successive swabs containing diiute nitricacid, distilled water and reagent acetone until residual contamination wascompletely removed.Weights were obtained to 0.0001 g on a calibrated·analytical balance.The wires were then mounted for counting by ga.-n:ma rayspectrometry.The activation products were analyzed by gamma ray spectrometryusing a 3 in. diameter x 3 in. long Nal(Tl) scintillation crystal detector and a 400 channel analyzer capable of 7 .O percent resolution FHH:l (full widthhalf maximum) at the 0.662 MeV13 7Cs-137mBa gamma ray energy level.

. 13The analyzer was calibrated with standard reference materials obtainedfrom the National Bureau of Standards.To calculate neutron flux fromthe dosimeter gamma activities at time of removal from the reactor, aknowledge of the reactor history and exact location of the samples wasrequired as shown in the following equation:AA Ncr [1 - exp(-A.ti)] or N cr [1 - -e x p-(--A-t-.-)-]wherel. neutron flux in n/cm 2-secAdisintegrations per second per gram attime of removal from reactorN number of atoms of target isotope pergram of dosimetercr· effective cros section at the samplelocation in cm t. time in the reactor (equivalent fulll.power seconds)A. isotope decay constant, sec-12The total neutron fluence is then equal to t. inn/cm .l.The exact capsule iocation is necessary in that the effectivecross section varies as a function of the neutron spectrum.Ai. ISN,a onedimensional transport code, was used to calculate the neutron spectrum atthe capsule

14- Charpy Impact PropertiesThe impact tests were performed. on a standard Wiedemann-Baldwinimpact machine in accordance with the recommendations of the pertinent-AS1M standard(14) The accuracy of the machine was verified within a6-month period prior to use with standards purchased from the U.S. ArmyMaterials and Mechanics Research Agency.TABLE 3. CALIBRATION DATA FOR THE BCL HOTLABORATORY CHARPY IMPACT MACHINEAverageBCL Energy,ft-lbGroupThe results are given in Table 3.Standar a)VariationAllowedActualEnergy,ft-lbLow Energy12.412.5-0.1 ft-lb 1.0 ft-lbMedium Energy41.543.2-3.9% 5.0%High Energy71.271.1 0.1% 5.0%(a) Established by U.S. Army Materials and Mechanics Research Center.The impact machine is shown in Figure 6.The Velocometer andDynamic Response Module associated with the instrumented Charpy testing aremounted on top of the impact machine.of the machine is used to recordThe oscilloscope located to the rightload timetraces during impact tests.As'IM procedures for specimen temperature control were utilized .The low temperature bath consisted of agitated methyl alcohol cooled withadditions of liquid nitrogen.The container was a Dewar flask which containeda grid to keep the specimens at least 1 in. from the bottom.The height ofthe bath was enough to keep a minimum of 1 in. of liquid over the specimens. The Charpy specimens were held at temperature for a minimum of at least theAS1M recommendedtime -

.·15 Cl914FIGURE 6.INS'lRUMENTED CHARPY MACHINEVelocometer and Dynamic Response Module areshown mounted on top of the Charpy impactmachine

. 16The tests above room temperature were conducted in a similarmanner except that a metal container with a liquid bath was used.Thebath used for temperatures from 70 to 212 F was water, and the bath usedfor temperature above 212 F was oil. · The baths were heated to temperatureusing a hot plate.The specimens were manually transferred from the temperature bathto the anvil of the impact machine by means of tongs that had also been'brought to temperature in the bat h.bath and impacted in less than 5 sec.The specimens were removed from theThe energy required to break the. specimens were recorded and plotted as a function of test temperature asthe testing proceeded.Lateral expansion was determined from measurements made with alateral expansion gage.Fracture appearance was estimated from observationof the fracture ·surface, and ·comparing the appearance of the specimen to anAS'IN fracture appearance chart. (lS) Hardness PropertiejHardness tests were done using a Wilson Rockwell hardness testingmachine.Before testing, the hardness machine values were checked againsttwo standardized test blocks having hardness values near the range of valuesexpected for the test specimens.Five impressions were made in each of thestandardtzed test blocks. -The average of these values were within 2 harc!nessnumbers of the standard values of the test blocks.All hardness readings on specimens were taken using the RockwellB scale.Specimens were Charpy impact specimens.Hardness readings weremade on the Charpy specimen surface opposite the notched surface.Fivereadings were made in the general region halfway between the specimen notchand one end of the speciraen.The minor load was first applied to seat theRockwell B ball penetrator on the specimen surface;The majorapplied, and the resultant dial hardness readings recorded l adwas then

17 After hardness readings were completed on the Charpy impactspecimens, the hardness machine was again checked using the same twostandardized test blocks.blocks.Five impressions were made in each of the twoThe average of these values were within 2 hardness numbers ofthe standard values of the test blocks.Tensile PropertiesThe tensile tests were conducted on a screw-driven Instrontesting machine having a 20,000 lb capacity.per min was used.A crosshead speed of 0.05 in.The deformation of the specimen was measured using astrain gage extensometer.The strain gage unit senses the differentialmovement of two extensometer extension arms attached to the specimen gagelength 1 in. apart.The extension arms are required for thermal protection.of the strain gage unit during the elevated temperature tests.Figure 7shows the extensometer extension arms and strain gage assembly used for tensile testing.The strain gage unit is shown at the bottom of the figurenext to the region of the extensometer arms where the unit is attachedduring testing.The extensometer was calibrated before testing using anInstron high-magnification drum-type extensometer calibrator.The irradiated tensile specimens wereand 550 F. estedat room temperatureElevated temperature tensile tests were conducted using a three-zone split furnace.The specimens were held at temperature before testing tostabilize the temperature.Temperature was monitored using a Chromel-Alwnelthermocouple in direct contact with the gage section of the specimen.Temperature was controlled within 5 F.The load extension data were recorded on the testing machine stripchart.Theyie dstrength, ultimate tensile strength, uniform elongation,and total elongation were determined.from these charts.The reduction inarea was determ.ined from specimen measurements made using a vernier caliper

18 P4973FIGURE 7. EXTENSOMETER EXTENSION ARMS AND STRAIN GAGEASSEMBLY USED FOR TENSILE TESTING

19 RESULTS AND DISCUSSIONNeutron DosimetryDosimeter wires from the neutron dosimeter monitor capsule andthe two capsule basket assemblies were recovered and analyzed as describedin the experimental procedures.A total of 18 iron and copper wires weregamma counted: three of each from the dosimetry monitor capsule, two of eachfrom the wall region capsule basket assembly, and four of each from the·topcore region capsule basket assembly.Results of the counting are given inTable 4 in terms of fluence greater than l MeV and O.l MeV.An average total integrated fast fluence greater than l MeV fromthe iron dosimeters from the neutron dosimeter monitor capsule of 0.983 x 10 16n/cm2was obtained.dosimeters of 1.15Somewhat higher values wer.e obtained from the copper'162x 10n/cm Generally, the iron value is consideredmore reliable due to its better known nuclear properties such as crosssection-neutron energy relationship and threshold energy. The iron dosimetersfrom the wall region capsule basket assembly showed essentially the same162average fluence ( l MeV) of 0.926 x 10n/cm The top core area showed alarge variation within the individual Charpy capsules. The measured i on18218fluence greater than l MeV ranged from 4.39 x 10n/cm to 10.2 x 102 182n/cm , with an average value of 7.11 x 10n/cm Several factors enterinto the calculations such as the reactor power history, neutron energyspec.trLUD at the particular location, and effective cross section for eachreaction as a function of the neutron spectrum.reactions are summarized in Table SA.Constants used for the two.The saturation ·factor was ·calculatedfroms.· .1-A.Nz::j lF . ( 1- eJi'Tj)e-A. (T-t .)wheres.1offull powerF.fraction'T length of time intervalJJ saturation correction factorT total irradiation time.th intervalt. time at end of JJN number of time intervalsA.l. decay constantiJ

TABLE 4.1DRESDEN UNIT NO, 3 FAST NEU'IRON DOSIMETRY RESULTS2FLUX RATE . nlcm -secFe54 l McV O.l MeV l McVCapsuleNo.Dosimeter Capsule.Dosimeter Capsule3.27xl03Dl'sir:1etcr CapEule3,24x10Avg,Wall C11p1iule Basket2'Wall npsule83.17xl02183 ,23xl02,97xl0BosketAvg.Coro Capsule Basket3 .J5xl02Core Capsule Basket2.53xl04Core Capsule Basket2 ,02xl0Core Capsule BasketAvg.8883 5,l3xl04.39xl0'884 ,60xl0.84.SOxlO4,02xl03,68xl03. 76xl03 ,55xl0,h79xl0J,67xl063 O. l McV88888885,70x106 .39xl08885,34xl085.98xl05.26xl085.6lxl05,44x10885 ,48xl0 114,15xl0 114,26xt0 113,34xt0116.94xlo 115,4ltxl0 111111113,3lx101111l .44xl02 .36x1011112 ,34x10' 3,83xl0( 1) Equivalent full power days of operation was calculated to be 352.5 days.(2) Date of capsule re·movol from the reactor was March 4, 1973.3,59xl0Cu2 ,6Jxl0l 1 B8xl03 ,C3xl011114,29x103 ,06x104.9Jxl01111FT.U ENCf: t I ( 1 2 ) n/ :.m 2Fe54 0.1 McV 1 MeV 1 l00.947xto0,926xl010.2xt07. 7lxlo6,15x104,39xio7. llxl01616161818181818l. 54xtol.58xl01616161.57 l.56xl0l.34xlol 140xt0l.37xl016. 7xt012 ,6xto10, lx107 .19x1011.6xlo161516161818181818cII 63 0.1 M.::V16l .10xl016l.22xlo16l.12x1016l. l5xl016l.08xl0l 116x1Cl .12xl013.0xl010.2xl08,0lx105 1 73xl09,24xlo16161818181818l. 74xl0l.95xl01616!,?8xl01610i.s2xio16l.60xl01, 7lxl016,1,66xI0 1621.lx101816,6xl0 181813.lxl0189.32xto1515.0xl0

. 21 TABLE SA.Reaction63Cu(n,a.)60Co54S4 .Fe(n,p) MnTargetTargetIsotope tionFactor100% Cu69.17s.o5.26y0.1161100% Fe:S.82l.S314d0.468STABLE SB. VALUES USED IN DRESDEN UNIT NO. 3DOSIMETRY CALCULATIONSACTIVATION CROSS SECTIONS IN BARNS FORDRESDEN NUCLEAR UNIT NO. 3S4Fe63CuCapsuleLocation l MeV O. l MeV l MeV 0 .1 MeVCapsule BasketAssemblyNear core topguide0.1440.08790.001130.000694Capsule BasketAssemblyWall-3S 00.2360.1590.004210.00284DosimeterCapsuleWall-27 S00.2250.1420.004210.00265

22For Dresden Unit No. 3 the average power was calculated to be0.575 times the 2527 MW(t) full power ratings. (16)Use of an average powerlevel rather than the detailed power history in the preceding equation wouldhave introduced errors of 10 percent and 2 percent in the case of Fe and Cureactions, respectively.Calculated fast neutron cross sections for the two reactions atthree locations and over two energy ranges are presented in Table SB.Tocalculate the effective cross section, it was necessary to know the neutronspectrum at the capsule location where the neutron energies would be at asignificantly higher range than the spectrum at the core edge.Figures 8,9, and 10 are plots of neutron flux as a function of neutron energy at thethree locations. (l6)These were calculated by using the one dimensionaltransport code, ANISN.The effective cross section cr lfrom the equationrc:o (E)cr(E)dEE OC(E)dEE l MeVwhere cr and are calculated over 27 energy groups MeVis calculated

.,.DRESDEN 2&32527·MW ·swR(275)M.(j NIT CJ R10 ::JJLL.10-l·w Nwt-a:Jwcc.'Z-2Ela: 10t-::JwL:lo-'I llJllll I 1111111L1.u1111L.JJJ.1wl I II 11ml. I 111111111 0-a1 Ou.1 0-71 0-G1 0-z;1 a I 11 lllJll1 0- I l llllLU.UUllU . . . .l.o.lo.1 ci l 0- 1l OuNEUTRBN ENERGY (MEVlFIGURE 8.CALCULATED NEUTRON FLUX--SPECIBUM FOR DRESDEN UNIT NO. 3 AT 275 nnq1v1F.TF.R MONITOR CAPSUT.E LOCATION (AFTER BRASHER AND TINMONS). 1'Jr.11·1'f'n"'-1l (f

DRESDEN 2527 M

unit no. 3 esw raz metal from capsule g3 29 table 12. charpy v-notch impact. test results for dresden unit no. 3 saw weld metal from capsule g3. 30 table 13. charpy .v-notch impact test results for dresden unit no. 3 saw haz metal from cap.sule g3 30 table 14.