ML17325A967

From kanterella
Revision as of 09:20, 29 June 2018 by StriderTol (talk | contribs) (Created page by program invented by StriderTol)
Jump to navigation Jump to search
Reduced Temp & Pressure Operation for Donald C. Cook Nuclear Plant Unit 1 Licensing Rept, Including FSAR mark-ups
ML17325A967
Person / Time
Site: Cook American Electric Power icon.png
Issue date: 10/31/1988
From: AUGUSTINE D B, CECCHETT D L
WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP.
To:
Shared Package
ML17325A960 List:
References
WCAP-11902, NUDOCS 8810190409
Download: ML17325A967 (12)


Text

MESTINGHOUSE CLASSIIIHCAP-11902 REDUCEDTEMPERATURE ANOPRESSUREOPERATION FORDONALDC.COOKNUCLEARPLANTUNIT1LICENSING REPORT0.L.Cecchett0.B.Augustine October1988eWESTINGHOUSE ELECTRICCORPORATION EnergySystemsBusinessUnitP.O.Box355Pittsburgh, Pennsy1vania 15230pop/g/'980a:1d/100588 cumulative fatigueusagefactorwascalculated tobe0.69whichislessthanthe1.0Codelimit.Thisvalueincludesthethermalstressduetothenon-linear portionofthethermalgradientforconservatism.

Asubstantial reduction inthemaximumrangeofstressintensity couldbeachievedifthenon-linear thermalgradientcontribution wereneglected aspermitted bytheASHECode.3.10.1.2ReactorVesselIntegrity Anevaluation oftheimpactofreratingonreactorvesselintegrity forneutronembrittlement wasperformed.

Neutronfluencechangesforthereratingwerecalculated.

Usingtheserevisedfluencesandthosefromotherrelevantsystemsparameters associated withthererating, theassessment includedreviewofsurveillance capsulewithdrawal schedules, thescheduleofapplicability oftheplantheatupandcooldownlimits,and10CFR50-~~~~~~~~~~~~AppendixGanalyses, including averification ofplantspecificmaterialproperties.

Arevisiontothecalculations usedinthesubmittal totheNRCformeeting-therequirements ofthepressurized thermalshock(PTS)rulewereperformed.

Finally,aninitialevaluation oftheimpactofreratingonthePTSriskofvesselfailurewascarriedouttoconfirmtheapplicability ofthescreening criteriainthePTSrulefortheCookNuclearPlantreactorvessels.ThereratingaffectsthePTStransient initiating temperature whichislowerthanthatusedinthegenericPTSriskanalyseswhichsupportthescreening criteria.

~Neutrontransport calculations havebeencompleted ataconservatively highpowerlevelof3600HWt,andreducedtemperature/pressure conditions forCookNuclearPlantUnit1.Resultsoftheseanalyseshaveindicated thatinadditiontotheincreased reactorpower,operation oftheunitswithreducedcoolanttemperatures, particularly inthedowncomer regions,alsohasasignificant impactonthefastneutronexposureratesincidentonthepressurevessel.Alsoimpactedaretherelationships amongtheneutronexposureratesatsurveillance capsulelocations andthoseatpositions withinthepressurevesselwall;i.e.,capsuleleadfactors.Agd~~9tzpgQg78739a:1d/092988 3.10-5

~I Toprovideaboundingevaluation ofthesevariouseffects,calculations wereperformed forthecurrentlicensedconditions aswellasforupratedpowerwithbothmaximumandminimumdowncomer temperatures.

Theresultsofthesestudiesaresummarized inTables3.10.1-1and3.10.1-2.

Anexamination ofTables3.10.1-1and3.10.1-2showsthattheimpactofhigherpoweroperation andchangedcoolanttemperatures isgreaterontheabsolutemagnitude oftheneutronexposureratethanontherelativebehaviorofneutronfluxdistributions asreflected incapsuleleadfactors.Twosetsofdatahavebeenprovidedtoestablish upperandlowerboundexposures forCookNuclearPlantUnit1.Theupperlimitconditions areconsistent withassuminganupratingattheonsetofthenextfuelcyclewithcontinued operation ataninlettemperature of547'Fforunit1.Lowerboundfluenceestimates werebasedonnoupratinginpowerlevel,butwithfutureoperation occurring atreducedT;i.e.,theinlettemperature wasassumedavg'obe512'F.Theselowerboundfluenceestimates arelowerthanthoseatcurrentoperating conditions.

Reviewoftheheatupandcooldowncurvesthatwerepreviously generated bySouthwest ResearchInstitute indicatethatthesecurvesweregenerated inaccordance withRegulatory Guide1.99-Revision 1.PerNRCGenericLetter88-11,datedJuly12,1988,allutilities mustsubmittotheNRCbyNovember1988theresultsoftheirtechnical analysisrelativetotheimplementation ofRegulatory Guide1.99-Revision 2,whichwasofficially issuedinMay1988.Giventhisregulatory change,theeffectofreratingshouldbeincorporated IIintofuturecalculations thatwillbeperformed forrevisingheatupandcooldowncurvesinaccordance withthislatestrevisionofRegulatory Guide1.99.Theeffectofthereratingisdeemedtonotbesignificant.

Thechangesinthesystemsparameters associated withthereratinghavebeenjudgedtonothaveanysignificant impacton10CFRPart50-AppendixGanalysis.

8139e:1d/093088 3.10-6IZpa~+g7 S

TheCookNuclearPlantUnit1reactorvesselbeltlineregionmaterialproperties wereverifiedagainstthelatestavailable information invariousindustrydata.basesandsurveillance capsulereports.Theproperties definedfromthelatestinformation areconsistent withthoseusedinpriorutilitysubmittals totheNRCrelativetomeetingtherequirements ofthePTSrule.SincethecoreloadingpatternwiIIbechangingasaresultofthererating, anupdatetothePTSsubmittal willberequiredasstatedinthePTSRule.Revisedcalculations wereperformed forthereratingusingthecurrentPTSRulemethodology andthelatestprocedure specified byRegulatory Guide1.99-Revision2.AsstatedinNRCGenericLetter88-11,thestaffispresently considering anamendment tothePTSRule,10CFR50.61,thatwillreplacetheequations forRTptsgiveninparagraph (b)(2)withthecalculation procedure inSectionC.lofRevision2toRegulatory Guide1.99,buttheywillnotchangethescreening criteria.

AlltheRTptsvaluesremainbelowtheNRCscreening valuesforPTSusingtheprojected fluencevaluesthatarebaseduponreratedconditions throughthelicenseexpiration.

ThehighestRTptsvalue(265'F)wascalculated atthecircumferential weldoftheCookNuclearPlantUnitIreactorvessel,usingthemethodology ofRegulatory Guide1.99Revision2.Onthebasisofprobabilisticworkdescribed inthePTSRule,theNRCstaff'oncluded thatPHRvesselswithconservatively calculated valuesofRTndt(i.e.,RTpts)lessthan270'Fforplatematerialandaxialwelds,andlessthan300'Fforcircumferential weldspresentanacceptably lowriskofvesselfailurefromPTSevents.Thisevaluation, however,didnottakeintoaccounttheimpactofrerating, whichcausespotential PTStransient scenarios tobeginfromalowersystemtemperature.

81390:1d/092988 3.10"7 Aninitialevaluation wasperformed todetermine theimpactofreratingonthe~~~~~~~applicability ofthePTSscreening criteriaintermsofriskofvesselfailure.Aprobabilistic fracturemechanics sensitivity studyoflimitingPTStransient characteristics, startingfromaloweroperating temperature, showedthattheconditional probability ofreactorvesselfailurewillnotbeadversely affected.

Therefore, theoverallriskofvesselfailurewillnotbeadversely impactedmeaningthatthatthescreening criteriainthePTSRulearestillapplicable fortheCookNuclearPlantUnit1reactorvesselrelativetoreratedconditions.

813S@:Id/0929883.10-8 TABLE3.10.1-1FASTNEUTRON(E>1.0MeV)FLUENCEPROJECTIONS FORCOOKNUCLEARPLANTUNIT1Unit122.89EFPYAllplates;Weld9-442Welds2-442B,2-442C,3-442A,3-442CUerBound1.84x101.19x10LowerBound1.55x101.01x10Weids2-442A,3-442B5.92x105.01x108139e:1d/092988 3.10-9 I

TABLE3.1.0.1-2 SURVEILLANCE CAPSULELEADFACTORSFORCOOKNUCLEARPLANTUNIT14'aosules 40'apsules Unit1BaseCase(3250Wt,536'FDowncomer) 1.34.2Unit1AtUpratedPower(3588HMt,547'FDowncomer) 1.34.2Unit1AtUpratedPower(3588HMt,512'FDowncomer) 1.34'8139e:1d/092988 3.10"10pffQQIPNCJtjI2PV~<7 E

TABLE4.1-1SYSTEMDESIGNANDOPERATING PARAMETERS iPlantdesignlife,yearsNumberofheatcransferloopsDesignpressure, psigNominaloperating

pressure, psigTocalsystemvolumeincluding pressurizer andsurgeline(ambientconditions),

ft(estimated) 3Systemliquidvolume,including pressurizer andsurgeline(ambientconditions),

fcSystemliquidvolume,including pressurizer 3max.,guaranteed power,fc(escimac'ed)

TocalReactorheatoutput(100%power)Btu/hr402485223512,50011,89211,78011,089x10(Unit1)6(3250MVt)11,641x10(Unit2)6(3411HPt)Unit1BoundingConditions forReracingLower/Upper Unit2Reactorvesselcoolanttemperature atfullpower:Inlet,nominal,F0Outlet,nominal,F0Coolanttemperature riseinvessel0acfullpower,avg.,FTotalcoolantflowrace,lb/hrx106Sceampressureacfullpo~er,psiaSteamTemp.Qfullpower,FTotalReactorCoolantVolumeatambientcondicions, ft3514.9/545.2 579.1/607.5 64.2/62.3 139.0/133.9 618/820489'/521.112,438541.3606.464.8134.6820521.112,4704.1-25July1990