ML17334B507

Submits Response to NRC 940422 Ltr,Supplying Sets of Summary Tables Containing Pressurized Thermal Shock & Upper Shelf Energy Info for Plant,Per GL 92-01

ML17334B507
Person / Time
Site:	Cook
Issue date:	05/20/1994
From:	FITZPATRICK E INDIANA MICHIGAN POWER CO. (FORMERLY INDIANA & MICHIG
To:	RUSSELL W T NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
AEP:NRC:1173C, GL-92-01, GL-92-1, TAC-M83453, TAC-M83454, NUDOCS 9405310207
Download: ML17334B507 (27)

Text

-ACCELERATED DISTRIBUTION DEMONSTION SYSTEMREGULATORY INFORMATION DISTRIBUTION SYSTEM(RIDS)

SUBJECT:

SubmitsresponsetoNRC940422ltr,supplying setsofsummarytablescontaining pressurized thermalshock6uppershelfenergyinfoforplant,per GL92-01.DSIZE.$0P~$tructural Integrity 1/DISTRIBUTION CODE:A028DCOPIESRECEIVED:LTR ENCLTITLE:GenericLetter92-01Responses (ReactorVesselNOTES:RECIPIENT COPIESIDCODE/NAME LTTRENCL"PD3-1PD11RECIPIENT IDCODE/NAME HICKMAN,J COPIESLTTRENCL22DACCESSION NBR:9405310207 DOC.DATE:

94/05/20NOTARIZED:

NODOCKETFACIL:50-315 DonaldC.CookNuclearPowerPlant,Unit1,IndianaM0500031550-316DonaldC.CookNuclearPowerPlant,Unit2,IndianaM05000316AUTH.NAMEAUTHORAFFILIATION FITZPATRICK,E.

IndianaMichiganPowerCo.(formerly Indiana!!'ichigan EleRECIP.NAME RECIPIENT AFFILIATION RUSSELL,W.T.

DocumentControlBranch(Document ControlDesk)INTERNAL:

NRR/DE/EMCB NRR/DRPE/PDI-1 NUDOCS-ABSTRACT OGC/HDS2RES/DE/MEB EXTERNAL:

NRCPDR221111101111NRR/DORS/OGCB NRR/DRPWOC/LPJ3CB M322hOlNSIC1111101111DDNOTETOALL"RIDS"RECIPIENTS:

DDPLEASEHELPUSTOREDUCEWASTE!CONTACTTHEDOCUMENTCONTROLDESK,ROOMPl-37(EXT.20079)TOELIMINATE YOURNAMEFROMDISTRIBUTION LISTSFORDOCUMENTS YOUDON'TNEED!TOTALNUMBEROFCOPIESREQUIRED:

LTTR15ENCL13 4IkII~a IndianaMichiganPowerCompanyP.O.Box16631Columbus, OH43216ÃIMEMSlMASNCMMWNPWMAEP:NRC:1173C DonaldC.CookNuclearPlantUnits1and2DocketNos.50-315and50-316LicenseNos.DPR-58andDPR-74RESPONSETOREQUESTFORVERIFICATION OFINFORMATION SUPPLIEDFORGENERICLETTER92-01,REVISION1(TACNOS.M83453andM83454)U.S,NuclearRegulatory Commission DocumentControlDeskWashington, D.C.20555Attn:W.T.RussellMay20,1994

References:

1)NRCletterfromJohnB.HickmantoMr.E.E.Fitzpatrick dated,April22,1994.2)LetterNo.AEP:NRC:1173 fromMr.E.E.Fitzpatrick toT.E.Murley(NRC)dated,July13,1992.3)LetterNo.AEP:NRC:1173A fromMr.E.E.Fitzpatrick toT.E.Murley(NRC)dated,November29,1993.4)LetterNo.AEP:NRC:1173B fromMr.E.E.Fitzpatrick toT.E.Murley(NRC)dated,January24,1994.Thisletterissubmitted inresponsetoyourApril22,1994,letterwhichsuppliedtwosetsofsummarytablescontaining pressurized thermalshock(PTS)anduppershelfenergy(USE)information foreachoftheDonaldC.CookNuclearPlantUnits.Thosesummarytablesweredeveloped byyourStaffbasedonourresponses toGenericLetter(GL)92-01,Revision1,"ReactorVesselStructural Integrity",

andonpreviously docketedinformation.

Specifically, inyourApril22,1994letter,yourequested thatweverifythattheinformation wesuppliedinresponsetoGL92-01,Revision1,hasbeenaccurately enteredinthesubjectsummarytables.QAgg~~J'i'4053i0207.'.940520

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ADGtK,05000315'P"'"-"--~:,.'"PDR',~

Mr.W.T.Russell-2AEP:NRC:1173C Asrequested, wehavereviewedandverified, withtheexceptions notedinEnclosure 1tothisletter,theaccuracyofthePTSandUSEsummarytables.Forclarity,acopyofthePTSandUSEtables,annotated withourcomments, isincludedasEnclosure 2tothisletter.Sincerely,

~~E.E.Fitzpatrick VicePresident drEnclosures cc:A.A.BlindG.CharnoffJ.B.Martin-RegionIIINFEMSectionChiefNRC'Resident Inspector J.R.Padgett

<OSgi020)ENCLOSURE 1TOAEP:NRC'1173C COMMENTSONPRESSURIZED THERMALSHOCKANDUPPERSHELFENERGYSUMMARYTABLES Enclosure 1toAEP:NRC:1173C Page1DonaldC.CookUnit1SummaryFileforPressurized ThermalShockThe32EFPY/EOLIDneutronfluenceof1.41xE19n/cm~ishighfornozzleshellplatesB4405-1,-2,and-3,andthenozzle/intermediate shellaxialandcircumferential welds1-442A/C,and8-442respectively sincetheplatesandweldsarelocatedabovethecoreaffectedheight.TheDonaldC.CookUnit1IDneutronfluenceat32EFPY/EOLfortheabovementioned platesandweldshasbeenestimated byWestinghouse at1.10xE18n/cm~.Westinghouse usedthe1.1xE18n/cm~fluencevalueindeveloping theDonaldC.CookUnit1USEspresented inWCAP-13587 "ReactorVesselUpperShelfEnergyBoundingEvaluation forWestinghouse Pressurized WaterReactors."

WCAP-13587 hasbeenreviewedbytheNRCOfficeofNuclearReactorRegulation, andisthesubjectoftheirsafetyassessment, datedApril21,1994(seeAttachment 1toEnclosure 1).Fortheaboveplatesandwelds,thevalueof1.41xE19shouldbereplacedwith1.10xE18.2.Asidentified onpage2-9oftheDonaldC.CookUnit1PTSevaluation, datedMarch1990(seeAttachment 2toEnclosure 1),the32EFPY/EOLIDneutronfluenceforthelongitudinal welds2-442A/Cand3-442A/Cis0.95xE19n/cm~.TheUnit1PTSreportwasincludedasAttachment 15totheGenericLetter92-01response, AEPletterNo.AEP:NRC:1173 datedJuly13,1992.3.Asidentified onpage2-8oftheDonaldC.CookUnit1PTSevaluation, datedMarch1990(seeAttachment 2toEnclosure 1),thepercentCuforaxialwelds1-442A/C, 2-442A/C, and3-442A/Candcircumferential weld9-442isestimated at0.28percent.Again,theUnit1PTSreportwasalsoincludedasAttachment 15totheGenericLetter92-01response, AEPletterNo.AEP:NRC:1173 datedJuly13,1992.The0.28percentCuvaluemaychangeasadditional information becomesavailable; however,thepercentCuvalueof.27shouldbereplacedwith.28fortheabovewelds.4,TheUnirradiated UpperShelfEnergyvaluesarenotincludedinthePTSTable,andassuch,thefootnoteshouldberemoved.

I Enclosure 1toAEP:NRC:1173C Page2DonaldC.CookUnit2SummaryFileforPressurized ThermalShock5.Asidentified onpage8oftheDonaldC.CookUnit2PTSevaluation datedFebruary1993(seeAttachment 3toEnclosure 1),the32EFPY/EOLIDneutronfluenceforthelowershellplatesC5540-2andC5592-1is1.71xE19n/cm~.Fortheaboveplates,thevalueof1.71xE18shouldbereplacedwith1.71xE19.TheUnit2PTSevaluation wasnotincludedwiththeGenericLetter92-01response; however,itwassubmitted perAEPletterNo.AEP:NRC:0561F datedApril12,1993.Asidentified onpage7oftheDonaldC.CookUnit2PTSevaluation datedFebruary1993(Attachment 3toEnclosure 1),thepercentNivalueforintermediate shellplateC5556-2is0.57,thepercentCuvalueforintermediate shellplateC5521-2is0.125,andthepercentNicontentforlowershellplateC5592-1is0.59.Therespective percentCuandNivaluesfortheseplatesshouldbereplacedwiththevaluesspecified inthisparagraph.

D.C.CookUnit1SummaryFileforUpperShelfEnergyThechangeinthepercentCucontentoftheaxialandlongitudinal welds,identified inCommentNo.3,resultsintheneedfortheNRCtore-calculate 1/4TUSEatEOL.Usingeitherthe0.27or0.28percentCuvalue,therevised1/4TUSEexceedstheminimumUSEEnergycriteriaof50FT-Lbs.ThepercentCuvaluesdonotappearintheUSETables,andassuchthefootnoteshouldberemoved.9.Itshouldbenotedthat,withthecorrection oftheIDneutronfluencevaluesforthenozzleshellplatesandthenozzle/intermediate shellaxialandcircumferential weldsasindicated incommentNo.labove,the1/4TneutronfluenceatEOLshouldalsobere-calculated bytheNRC.Westinghouse hasdetermined thatthe1/4TneutronfluencesatEOLforthenozzleshellplatesandthenozzle/intermediate shellaxialandcircumferential weldsare5.77xE17n/cm~.

lA.~

~gAREJIGktt44$~~c4~eUNITEDSTATESNUCIFARREGULATORY COMMISSION ygp,sHINGTON.

D.C.2055~<gqp>1$Hr.WilliamH.RasinVicePresident andDirectorTechnical DivisionNuclearHanagement andResources Council1776EyeStreet,N.W.,Suite300Washington, DC20006-3706

SUBJECT:

SAFETYASSESSHENT OFREPORTWCAP-13587, REVISION1,"ReactorVesselUpperShelfEnergyBoundingEvaluation forWestinghouse Pressurized WaterReactors,"

September 1993

DearHr.Rasin,

ByletterdatedHarch16,1993,theNuclearHanagement andResources Council(NUHARC)submitted areportpreparedbytheWestinghouse ElectricCorporation fortheWestinghouse Owners'roup (WOG)entitled, "ReactorPressureVesselUpperShelfEnergyBoundingEvaluation ForWestinghouse Pressurized WaterReactors,"

WCAP-13587, Revision0.ThereportwasprovidedtoNRCassupplemental information inresponsetoGenericLetter(GL)92-01.Noreviewandapprovalwasrequested.

Thereportisintendedtodemonstrate throughfracturemechanics analysesthatthereexistmarginsofsafetyagainstfractureequivalent tothoserequiredbyAppendixGofASHECodeSectionIIIforbeltlinematerials havinguppershelfenergy(USE)valuesbelowthescreening criteriaof50ft-lb.ByletterdatedJuly1,1993,theNRCissuedarequestforadditional information (RAI)concerning thereport.ThereplytotheRAIwasreceivedbyNRConAugust20,1993andtheNRCwasnotifiedthatthereportwouldberevisedbasedontheRAI.WCAP-13587, Revision1,wassubsequently submitted toNRCthroughNUHARCbyletterdatedSeptember 30,1993.TheHaterialsandChemicalEngineering Branchhascompleted asafetyassessment ofRevision1ofthereport.Theenclosure containsthesafetyassessment.

Thestafffindsthemethodology employedandtheanalysisperformed fortheWOGtobeacceptable exceptasnotedintheenclosure.

Thereportdidnotcontainanequivalent marginsanalysisbasedonweldmentproperties becausetheWOGconcluded thatallofthebeltlineweldswouldbeabove50ft-lbatendoflicense(EOL).AspartoftheGL92-01review,thestaffwillbeevaluating eachbeltlineweldfortheWOGplantstodetermine ifthescreening criterion willbemetatEOL.Individual licensees desiringtoreference WCAP13587,Revision1,asthebasisforaddressing theUSErequirements of10CFR50,AppendixGmustconfirmthespecificplantapplicability byeitherdemonstrating thatallbeltlineweldswillhaveEOLCONTACT:E.Hackett,301-504-2751 USEabove50ft-lborthattheboundingplateusedinthereporthasalowerJ-Rcurvethananyotherbeltlinematerialinthevessel.Further,individual.

licensees mustrequestapprovalinaccordance with10CFR50,AppendixG.Thestaffalsoconcluded thatcomparison ofappliedfracturedrivingforcewithmaterialfractureresistance wasoverlyconservative forsomeofthecasesanalyzed.

Thisissue.wasaddressed foralimitingplantspecificcasebyletterdatedDecember21,1993,andtheWOGispreparing arevisiontothereportwhichaddresses allofthecasesconsidered.

'fyouhaveanyquestions, pleasecontactEdHackettofmystaffat301-504-2751.H.WayneHodges,ActingDirectorDivisionofEngineering OfficeofNuclearReactorRegulation

Enclosure:

Asstated ENCLOSURE SAFETYASSESSHENT BYTHEOFFICEOFNUCLEARREACTORREGULATION REACTORVESSELUPPERSHFBOUNDINGEVALUATION FORWESTINGHOUSE PRESSURIZED MATERREACTORSMCAP-13587 REVISION11.0REVIEWSUHHARYThestaffhasevaluated theequivalent margihsanalysispresented inreportMCAP-13587, Revision1,submitted bytheWestinghouse ElectricCorporation fortheMestinghouse Owners'roup (WOG).Thestafffindsthemethodology employedandtheanalysisperformed fortheWOGtobeacceptable exceptasnotedherein.Thereportdidnotcontainanequivalent marginsanalysisbasedonweldmentproperties becausetheWOGconcluded thatallofthebeltlineweldswouldbeabove50ft-lbatendoflicense(EOL).AspartoftheGL92-01review,thestaffwillbeevaluating eachbeltlineweldfortheWOGplantstodetermine ifthescreening criterion willbemetatEOL.Individual licensees desiringtoreference WCAP13587,Revision1,asthebasisforaddressing theUSErequirements of10CFR50,AppendixGmustconfirmthespecificplantapplicability byeitherdemonstrating thatal.lbeltlineweldswillhaveEOLUSEabove50ft-lborthattheboundingplateusedinthetopicalreporthasalowerJ-Rcurvethananyotherbeltlinematerialinthevessel.Further,individual licensees mustrequestapprovalinaccordance with10CFR50,AppendixG.Thestaffalsoconcluded thatcomparison ofappliedfracturedrivingforcewithmaterialfractureresistance wasoverlyconservative forsomeofthecasesanalyzed.

Thisissuewasaddressed foralimitingplantspecificcasebyletterdatedDecember21,1993[17],andtheMOGispreparing arevisiontothereportwhichaddresses allofthecasesconsidered.

2.0INTRODUCTION

ByletterdatedHarch16,1993,theNuclearManagement andResources Council(NUHARC)submitted areportpreparedbytheMestinghouse ElectricCorporation fortheMOGentitled, "ReactorPressureVesselUpperShelfEnergyBoundingEvaluation forWestinghouse Pressurized WaterReactors,"

WCAP-13587, Revision0[1].ThereportwasprovidedtoNRCassupplemental information inresponsetoGL92-01[2].Noreviewandapprovalwasrequested.

Thereportisintendedtodemonstrate throughfracturemechanics analysesthatthereexistmarginsofsafetyagainstfractureequivalent tothoserequiredbyAppendixGofASNECodeSectionIIIforbeltlinematerials havingUSEvaluesbelowtheNRCscreening criteriaof50ft-lbin10CFR50,AppendixG.ByletterdatedJuly1,1993,theNRCissuedarequestforadditional information (RAI)onthereport[3].ThereplytotheRAIwasreceivedbytheNRConAugust20,1993andtheNRCwasnotifiedthatthereportwouldberevisedbasedontheRAI.

WCAP-13587, Revision1[4],incorporating theresponses totheRAI,wassubsequently submitted totheNRCthroughNUMARCbyletterdatedSeptember 30,1993.3.0APPCARGUATORYRURMNTSANUIDNSRegulatory requirements foruppershelfsafetymarginsarecontained inAppendixGofTheCodeofFederalRegulations, Title10,Part50(10CFR50).

AppendixGrequiresthattheinitialunirradiated CharpyV-Notch(CVN)uppershelfenergyatthestartofvessellifebenolessthan75ft-lbandthatthevesselmaintainanuppershelfenergylevelofnolessthan50ft-lbthroughout theservicelife.Ifitisanticipated thatavesselmightfallbelow50ft-lbbeforeEOL,ananalysismustbesubmitted whichdemonstrates "marginsofsafetyagainstfractureequivalent tothoserequiredbyAppendixGoftheASMECode."ThisanalysisissubjecttotheapprovaloftheDirector, OfficeofNuclearReactorRegulation.

Guidelines thatthestafffindsacceptable forconducting equivalent marginsanalysesarecontained inASMECodeCaseN-512[5]anddraftRegulatory GuideDG-1023,"Evaluation ofReactorVesselswithCharpyUpperShelfEnergylessthan50ft-lb"[6].

DG-1023incorporates thecriteriaofCodeCaseN-512and.providesadditional guidanceonmaterialproperties andtransient selection.-

DG-1023wasreleasedbyNRCforpubliccommentonOctober1,1993.NUREG/CR-.

6023[7]presentstheresultsofgenericboundingequivalent marginsanalysesconducted

.according toCodeCaseN-512guidelines forbothPWRsandBWRs.Asthemajorityoflicensees donothavefracturetoughness"information fortheirlimitingvesselmaterials, CVNdataistypically usedtoestimatethefracturetoughness.

Regulatory Guide1.99,Revision2[8]providesaprocedure forestimating thedecreaseinCVNuppershelfenergyasafunctionofcoppercontentandfluence.NUREG/CR-5729

[9]providesempirically derivedmodelsforpredicting materialfracturetoughness (J-Rcurves)fromCVNdataorchemicalcontentandfluence.TheNUREG/CR-5729 modelsareapplicable tothemajorityofRPVmaterials.

NRCBranchtechnical positionMTEB5-2[10]providescriteriaforestimating theCVNtoughness forthetransverse orientation fromlongitudinal dataforplatematerials.

The50ft-lbcriterion in10CFR50,AppendixGisforCVNdatafromtransversely orientedspecimens inplateorforwelds.Thetransverse orientation inplatematerialhaslowerimpactproperties thanthelongitudinal orientation.

Theimpactproperties oftheweldmetalarenotdifferentiated basedonorientation.

4.DMILJPIITheWOGemployedtheprocedures andcriteriaofASMECodeCaseN-512[5]toperformtheequivalent marginsanalysis.

ForservicelevelsAandB,theWOGperformed ananalysisforthelimitingnormaloperation cooldownrate(100'F/hr).

Theanalysisisconsistent withtheguidelines providedinCodeCaseN-512[5]andDG-1023[6].Inaccordance withboththeCodeCaseandDraftRegulatory Guide,theWOGassumedaquarterthickness depthflawforLevelsAandBandaflawdepthofupto1/10ofthebasemetalwallthickness

't pluscladdingforLevelsCandD.Theflawgeometryconsidered forallserviceconditions wasasemi-elliptical surfaceflawwitha6:1aspectratio.AquestionraisedintheRAI[3jconcerned theissueofwhetherbothaxialandcircumferential flawshadbeenaddressed asrequiredbytheCodeCase.TheresponsetotheRAIt3]citedthatbothcaseswereconsidered andtheappliedfracturedrivingforcefortheaxialflawswasinallcasesgreaterthanthose,forthecircumferential flaws.Consequently, theaxialflawcaseswereconsidered limiting.

TheRPVbeltlinebasematerials coveredbytheWOGincluded:

(1)A302GradeA(Plate)(2)A302GradeB(Plate)(3)A533GradeB,Class1(Plate)(4)A508Class2(Forging)

(5)A508Class3(Forging)

TheRPVbeltlineweldscoveredbytheWOGincludethoseproducedusingthefollowing fluxes:(1)Linde1092(2)Linde1091,(3)Linde0091(4)Linde124(5)UH89(6)ARCOSB5(7)GrauLo(8)SMIT89Linde80weldments werenotincludedintheWOGreport.TheWOGmaintains that"weldments fabricated withfluxesotherthanLinde80willnotexhibitlessthan50ft-lbduringservice."

Weldments willbediscussed furtherinSection4.2.Table1providestheWOGoverallminimumacceptable USEvaluesbyplanttype(2,3or4loop)fromtheequivalent marginsanalysis.

ThevaluesinTab'le1arebasedonfractureproperties forplateandforgingmaterials.

Noanalysiswasperformed basedonweldmentproperties sincetheWOGmaintains thatalloftheir'weldments willexceed50ft-lbatEOL~Theequivalent marginsanalysiscomparedtheEOLUSEvalueforeachplantwiththeminimumacceptable USEvaluesshowninTable1:TABLE1MinimumAcceptable USEValuesFromWCAP13587,Revision1CASELOWESTUSEft-lb2Loo3Loo4Loo294243

~f~'~Iw.'heEOLUSEvaluesforeachplantweredetermined inaccordance withthemethodology providedinRegulatory Guide1.99,Revision2[8].Theadequacyoftheequivalent marginsanalysiscanbedetermined fromthefollowing considerations:

(I)selection ofmechanical properties, (2)thedetermination ofpredicted EOLUSEvalue,(3)selection ofthemodelforgenerating thefracturetoughness data(J-Rcurves),(4)selection ofthelimitingtransients, (5)thecalculation forappliedfracturedrivingforce(J,~~)and,(6)theboundingnatureoftheanalysis.

4.IMechanical ProertiesPlantspecificvaluesoftensilemechanical properties foralloftheWOGvesselmaterials wererequested intheRAI[3].TheWOGinsteadchosetoboundthemechanical properties foralloftheplantsbyusingtheASHECodeminimum.allowable mechanical properties at600'F.Thestress-strain curveusedintheequivalent marginsanalysiswasgenerated usingtypicaldataforcarbonsteelandthenadjusting thecurvetomatchtheASHECodeminimumvalues.Thestafffindsthismethodology tobeacceptable.

4.2Predicted SglueInitialuppershelfenergyvaluesweredetermined frommaterialcertification andsurveillance testreports.GL92-01responses werealsousedtoobtainsupplemental CVNdata.TheEOLUSEvalueswereestimated usingtheRegulatory Guide1.99,Revision2methodology

[8].UsingthisapproachthreeplantswerefoundtohaveEOLUSEvaluesbelow50ft-lbasshowninTable2:TABLE2WOGPLantswithUSELessThan50ft-lbatEOLandComparison withMinimumAcceptable USEValuesFromTheEquivalent Ha'rginsAnalysisPLANTI.D.No.CASESHELLCOURSEHATERIALPREDICTED EOLUSEft-lbMINIHUHACCEPTABLE USEft-lb3Loo3LooLowerA302GrBIntermed.

A302GrA42374LooUerA508Cl249434LooIntermed.

A508Cl3Thelimitingmaterialforallthreeplantswaseitherplate(A302,A533)orforging(A508).Acomparison ofthepredicted EOLUSEvalueswiththeWOGminimumacceptable USEvaluesinTable,I,showsthatthepredicted plantdataisequaltoorboundedbytheminimumacceptable valuesforallthreeplants.Thesubjectreportalsonotedanadditional case(Plant16)whereEOLUSE.above50ft-lbwasnotdemonstrated foranA533Bplate.ItwasnotedbytheWOGthattheUSEvaluesfortheuppershellcourseofPlant16werebasedon-datafromunirradiated longitudinal specimens withlessthan100Kshear

6fractureindicating thatthetestsdidnotrepresent fulluppershelfbehavior.

ThelicenseeforPlant16hassubmitted anadditional analysisoftheCharpydatafortheirbeltlineplates[18j.Thissubmittal showsthattheuppershellcourseplateswillachieveanEOLfluenceofonly4.85E+17n/cmandtherefore thepercentdropinUSEwithirradiation islow(approximately 10K).Withthesmallpredicted dropinUSEaninitialvalueofonly56ft-lbsisrequiredfortheuppershellcourseplatestoremainabove50ft-lbtoEOL.Thesubmittal demonstrates that,althoughfullshearperformance wasnotachievedintheCVNtestsfortwooftheuppershellcourseplates,theextrapolation toanEOLUSEgreaterthan56ft-lbsforfullshelfperformance isreasonable.

Thestafffindsthisanalysistobeacceptable.

AstheMOGdidnotprovidealistingwhichidentified theWOGplantsandtheircorresponding USEdatabyname,confirmation oftheinputdata(chemistry andfluence)andcalculations onaplant-by-plant basiswasnotpossible.

Asstatedpreviously inSection4.0,theWOGmaintains that"weldments fabricated withfluxesotherthanLinde80willnotexhibitlessthan50ft-lbduringservice."

Table2-2inthesubjectreportconfirmsthisstatement byshowingalistingwithinitialUSEandprojected EOLUSEvalues~foreachplant.ThelowestEOLUSEvaluereportedwas50ft-lbforPlant17withARCOSB5flux.Aswasthecasewiththebasematerials, theWOGdidnotprovidealistingwhichidentified theWOGplantsandtheircorresponding USEdatabyname.Therefore, confirmation oftheinputdata(chemistry andfluence)andcalculations onaplant-by-plant basiswasnotpossible.

Further,sincetheminimumacceptable "SEvaluesfromtheequivalent marginsana'Iysis werebasedonfracturetoughness dataforplateorforgingmaterials, thesevalueswillnotapplytoweldments.

However,calculations performed forNUREG/CR-6023

[7jwiththeLinde80weldmodelhaveshownaminimumacceptable USEof41ft-lbforaPMR.Thestaffconsiders that,whileweldments fortheWOGplantsarenotlikelytobelimitingforUSE,thesubjectreportdoesnotprovidesufficient information tomakethisdetermination conclusively.

AspartoftheGL92-01review,thestaffwillbeevaluating eachbeltlineweldfortheWOGplantstodetermine ifthescreening criterion willbemetatEOL.4.3Selection oftheFractureTouhnessJ-RCurveModelTheJ-Rcurveinformation requiredfortheequivalent marginsanalysiswasgenerated fromtheboundingEOLUSEvaluescalculated foreachplantcategory(2loop,3loopand4loop).TheJ-RcurvesforRPVbasematerials wereobtainedfromCYNdatausingtheCharpymodelofNUREG/CR-5729

[9).Asstatedpreviously, theWOGmaintains thatalloftheWOGweldswillbeabove50ft-lbatEOLandtherefore didnotdevelopJ-Rdataforwelds.ForlevelsAand8theJ-Rcurvesforatemperature of390.5'Fwereused.Thisvaluerepresents thegreatesttemperature atthecracktipduringthe100'F/Hr.

cooldownfora1/4Tflawbasedonpeakstressresultsfroma2-Dfiniteelementanalysis.

ForLevelsCandDthetemperatures usedfortheJ-Rcurveswerefromtheappropriate transients (intherangeof400'F-500'F).Thestafffinds,theapproachtodeveloping theJ-RcurvedataforalloftheWOGbasematerials to.beacceptable withtheexception ofthemethodusedforA302B.ForA3028plate,theWOGconsiders the6TC(T)J-RcurvedataofNUREGCR/5265[ll]tobealowerboundfora50ft-lbA3028plate.TheMOGadjustedthe6Tdata forlowerUSEvaluesbydecreasing J,<by3Xperft-lbofCVNenergy.Thisrateofdecreasecorresponds toTeeratedetermined fromtheCharpymodelofNUREG/CR-5729

[9].Thestaffalsoconsiderthe6TA302BdataofNUREG/CR-5265tobealowerboundforA302B.However,thestafffindstheoverallJ-RCurveadjustment procedure forA302Btobeunacceptable forthefollowing reasons:(1)ThepercentdecreaseinJ,;,calculated toEOLforthelimitingA3025materialassumedtRaf.thematerialinNUREG/CR-5265

[11]hadaUSEof50ft-lb.However,theactualUSEfortheA302BmaterialinNUREG/CR-5265

[ll]is53ft-lb.Therefore theXdecreaseinJ<,<citedforA302Binthesubjectrepor'tshouldbeapproxImately 33Xasopposedto24X.(2)Theresulting J,.datawerenottemperature corrected.

ThedatafromNUREG/CR-5F63

[(1]weregenerated atatemperature of180'F.Thestaffmaintains thatatemperature correction isnecessary.

Onemethodthathasbeenproposedfordetermining thedecreaseinJ,,,withtemperature forNUREG/CR-5265

[11]materialiscontained inreference

[12].Usingtheequationprovidedinthisreference, thedecreaseinJ<withtemperature from180'Fto390'Fisapproximately 34'.Adjusting theanalysistoaccountfortheaboveyieldsaJ,,~<valueat0.1inchesofcrackextension (Jo)whichissignificantly less~ChanthatobtainedbytheWOG.A'ethodology foradjusting A302BJ-Rcurvedatawhichissimilartothatinreference

[12]andhasbeenfoundacceptable bythestaffiscontained intheBMROwnersGroupTopicalReportNEDO-32205

[13].ItshouldbenotedthattheA302BplatetestedforNUREG/CR-5265

[11]wasahighsulphurplatewhichreceivedaminimalamountofcrossrolling.Theresultant fractureproperties wereseverelydegradedbythepresenceoflargemanganese-sulfide(HnS)inclusions.

Forthesereasons,itisquestionable whethertheplatecanbeconsidered representative ofA302BwhichwouldhavebeenusedinRPVconstruction.

However,untilrecently, NUREG/CR-5265 represented theonlylargescalefracturedatathatwereavailable forA302B.Hence,thestaffhaveconsidered thesedatatobealowerboundforA302Bplate.Recentpreliminary fracturetestresultsfromtheOakRidgeNationalLaboratory (ORNL)onapotentially morerepresentative A302Bplateindicatevastlysuperiorproperties tothoseobtainedinNUREG/CR-5265

[11].Thest'affwillconsidertheORNLdataandotheravailable fracturedatainestablishing futurepositions forA302Bplatefractureresistance.

44SeletioniitiTransient Thesubjectreportusedthe100'F/hrheatup/cooldown caseasboundingforLevelsAandB.Thisisconsistent withtheevaluation performed inNUREG/CR-6023[7].ForLevelsCandDtheWOGusedbothpeakstressandtheoverallmagnitude ofthethrough-wall stressasthecriteriatodetermine theboundingtransients.

Theresulting temperatures atthecracktip(10Kofwallthickness

+cladding) were511FforPlant17and487'Ffortheremaining plants.Usingthesecriteria, itwasjudgedthatasmallsteamlinebreak(SLB)wasthelimitingLevelCtransient andlargelossofcoolantaccident JQ~~I~+(LOCA)'and largeSLBwerethelimitingLevelDtransients.

ForLevelD,thelargeSLBwasultimately selectedasthelimitingLevelDtransient asastressanalysisconducted bytheMOGshowedthatthelargeSLBproducedslightlylargerstressesatthecracktipfora1inchdeepflaw.InresponsetotheRAI,theWOGprovidedthepressureandtemperature histories forallofthetransients considered intheirassessment.

Basedonanexamination ofallofthetransients thestaffconcludes thatthelimitingCandDtransients selectedbytheWOGareacceptable.

4.5Calculation ofAliedFractureDrivinForceJTheMOGemployedtheprocedures ofCodeCaseN-512[5]andDG-1023[6]inthedetermination ofthefracturedrivingforce(J.)forLevelsAandB.Thestaffperformed anindependent evaluation oftfie7,.~calculations forthelimitingPlant7caseandwereabletoverifytheS(calculations.

ForlevelsCandDthepressureandtemperature histories forallofthetransients considered wereinputtoa2-Dfiniteelementmodelofthenuclearsteamsupplysystem(NSSS)usingtheWECAN[14]computercode.Theresulting stressdistributions forthelimitingtransients, whichincludedthecontributions ofthecladdingtothethermalstress,wereusedtocalculate J,~usingthePCFAD[15]computercode.Consistent withtheresultsoftlutefoundinganalysesperformed forNUREG/CR-6023, theMOGJ,,~valuesforLevelsAandBwerefoundtobecontrolling.

Thestafffindsthemethodology employedbytheWOGforcalculation ofthefracturedrivingforcetobeacceptable.

However,thestaffdiscovered thatthefinalanalysisforequivalent margin;wasoverlyconservative whencomparing thefracturedrivingforce(J<,~)withthematerialfractureresistance (J,-).ThiswillbediscusseP>n thenextsection.4.6BoundinNatureoftheAnalsisTheresultsoftheWOGequivalent marginsanalysisarepresented inTables3,4and5forLevelsA,8,CandD.TheseTablesshowacomparison betweentheapplieddrivingforceandmaterialresistance valuesforthethreegenericcases(2,3,and4loop)andtwoplant-specific cases.TheMOGconcluded thatinallcasesthecriteriaofCodeCaseN-512weremet(J,,,>J,~).However,inexamining thePlant7case(A302Bplate)inPetal),thestaffconcluded thatthematerialvalueforJpqdetermined bytheWOGwasnotacceptable (seeSection4.3).Thematerialvaluethatthestaffestimated forJ~,forPlant7waswellbelowtheappliedvaluecalculated bytheMOG.Furtherexamination ofthiscaserevealedthattheactualreasonforexceeding theCodeCaseN-512criteriawasthattheMOGhadconservatively comparedtheapplieddrivingforcefortheaxialfl~wwiththematerialresistance fortheweakorientation whichcorresponds tothecircumferential flaw(i.e.,meetingthecriteriaundertheseconditions assuresthatthecriteriawillalsobemetwhenthevaluesarecomparedassuggested bytheCodeCase.)Aconference call[16]withtheMestinghouse ElectricCorporation andthelicenseeforPlant7confirmed thatthisconservative analysiswasperformed forallofthecasesevaluated.

Thestaffconsiders thisanalysistobeoverlyconservative.

InarevisionletterdatedDecember21,1993[17]whichspecifically addresses thePlant7case,theWOGdemonstrated thattheappropriate comparison oftheappliedandmaterialvaluesshowsthattheCodeCaseN-512[5]criteriawere met.Theletter[17]alsoaddressed theUSEadjustment andtemperature correction concernsforA302Bplatethatwerediscussed previously inSection4.3,TheMOGispreparing amorecomprehensive revisiontothereportwhichwilladdressallofthecasesconsidered.

Thestaffconcludes that,intheinterim,thesubjectreportandthealternative evaluation providedintherevisionletterofDecember21,1993,demonstrate equivalent marginsofsafetyasperCodeCaseN-512[5]forWOGplateandforgingmaterials.

Forthecaseofwelds,asstatedpreviously, theWOGmaintains that"weldments fabricated withfluxesotherthanLinde80willnotexhibitlessthan50ft-lbduringservice."

However,theWOGdidnotprovidealistingwhichidentified theWOGplantsandtheircorresponding USEdatabyname.Therefore, confirmation oftheinputdata(chemistry andfluence)andcalculations onaplant-by-plant basiswasnotpossible.

Further,sincetheminimumacceptable USEvaluesfromtheequivalent marginsanalysiswerebasedonfracturetoughness dataforplateorforgingmaterials, thesevalueswillnotapplytoweldments.

Calculations performed forNUREG/CR-6023

[7]withtheLinde80weldmodelhaveshownaminimumacceptable USEof41ft-lbforaPWR.Therefore thestaffconsiders that,whileweldments fortheWOGplantsarenotlikelytobelimitingforUSE,thesubjectreportdoesnotprovidesufficient information tomakethisdetermination conclusively.

AspartoftheGL92-0Ireview,thestaffwillbeevaluating eachbeltlineweldfortheMOGplantstodetermine ifthescreening criterion willbemetatEOL.Inthesubjectreport,theMOGcitedaminimumacceptable USEvalueof29ft-lbforplatesandforgingsin2loopplants.Mhilenumbersthislowcanresultfromthecalculations andhavebeencitedelsewhere

['6],[7],theirsignificance isnotclearatthistimeandtheyrepresent anextrapolation ofthedatausedtodevelopthecorrelations inNUREG/CR-5729

[9].Thereisnotatpresentatechnical consensus ontheCVNenergylowerlimitforequivalent marginsanalyses.

However,valuesbelow30ft-lbforreactorpressurevesselsteelsarehighlysuspectassuchlowenergiesarelikelytobeassociated withductiletearingincombination withotherfracturemodes(e.g.,intergranular, incipient cleavage) notconsidered inthedevelopment ofthelowuppershelfcriteria.

5.0CONCLUSION

S Thestaffhasevaluated theequivalent marginsanalysispresented inreportWCAP-13587, Revision1,submitted bytheWestinghouse ElectricCorporation fortheWOG.Thestaffevaluation supportsthefollowing conclusions:

(1)Themethodology employedfortheWOGreportwasconsistent withtheguidelines inCodeCaseN-512[5]andDG-1023[6]andistherefore acceptable tothestaff.(2)(3)Thesubjectreportdemonstrates marginsofsafetyequivalent tothoseoftheASHECodeforWOGbeltlineplateandforgingmaterials.

Anequivalent marginsanalysisbasedonweldmentproperties wasnotperformed becausetheWOGconcluded thatalloftheWOGbeltlinewelds'ouldbeabove50ft-lbatEOL.AspartoftheGL92-01review,the

l410staffwillbeevaluating eachbeltlineweldfortheWOGplantstodetermine ifthescreening criterion willbemetatEOL.(4)Individual licensees desiringtoreference WCAP13587,Revision1,asthebasisforaddressing theUSErequirements of10CFR50,AppendixGmustconfirmthespecificplantapplicability byeitherdemonstrating

'hatallbeltlineweldswillhaveEOLUSEabove50ft-lborthattheboundingplateusedinthereporthasalowerJ-Rcurvethananyotherbeltlinematerialinthevessel.Further,individual licensees mustrequestapprovalinaccordance with10CFR50,AppendixG.(5)ThestafffindstheWOGapproachformodelingtheJ-RcurvebehavioroftheA302BplateinWCAP-13587, Rev.1,tobeunacceptable (seeSection4.3).However,theA302BJ-Rcurvemethodology employedintheplantspecificrevisionletterofDecember21,1993[17]includesappropriate adjustments forUSEandtemperature corrections andisacceptable tothestaff.(7)Thestafffindsthatthefinalcomparison ofappliedfracturedrivingforcewithmaterialfractureresistance wasoverlyconservative forallcasesanalyzed.

Thisissuewasadequately addressed foralimitingplantspecificcasebyletterdatedDecember21,1993[17],andtheWOGispreparing arevisiontothereportwhichaddresses allofthecasesconsidered.

Calculated minimum.acceptable USEvaluesbelow30ft-lbforreactorpressurevesselsteelsarehighlysuspectassuchlowenergiesarelikelytobeassociatedwithductiletearingincombination withotherfracturemodes(e.g.,intergranular, incipient cleavage) notconsidered inthedevelopment ofthelowuppershelfcriteria.

6.0REFERENCES

[2][3][4][5][6][8]WCAP-13587, Revision0,"ReactorVesselUpperShelfEnergyBoundingEvaluation.

for'estinghouse Pressurized WaterReactors",

S.TandonandT.R.Hager,Westinghouse ElectricCorporation,

February, 1993.GenericLetter92-01,Revision1,ReactorVesselStructural Integrity,.

10CFR50.54(f),

U.S.NuclearRegulatory Comnission, March6,1992.RequestforAdditional Information onWCAP-13587, "ReactorVesselUpperShelfEnergyBoundingEvaluation forWestinghouse Pressurized WaterReactors,"

U.S.NuclearRegulatory Commission, July1,1993.WCAP-13587, Revision1,"ReactorVesselUpperShelfEnergyBoundingEvaluation forWestinghouse Pressurized WaterReactors",

S.TandonM.J.HaloneandT.R.Mager,Westinghouse ElectricCorporation, September, 1993.CodeCaseN-512,"Assessment ofReactorVesselswithLowUpperShelfCharpyImpactEnergyLevels,"SectionXI,Division1,ASHEBoilerandPressureVesselCode,February12,1993.DraftRegulatory GuideDG-1023,"Evaluation ofReactorPressureVesselswithCharpyUpperShelfEnergyLessthan50ft-lb,"U.S.NuclearRegulatory Comaission, August,1993.NUREG/CR-6023, "GenericAnalysesforEvaluation ofLowCharpyUpperShelfEnergyEffectsonSafety.MarginsAgainstFractureofReactorPressureVesselMaterials,"

T.L.Dickson,USNRC,'ashington, DC,July1993.Regulatory Guide1.99,Revision2,"Radiation Embrittlement ofReactorVesselMaterials,"

U.S.NuclearRegulatory Comnission, Hay,1988.[9][10][12]NUREG/CR-5729, "Multivariable ModelingofPressureVesselandPipingJ-RData,"E.D.Eason,J.E.WrightandE.E.Nelson,USNRC,Washington, DC,1991.NUREG-0800, "Standard ReviewPlanfortheReviewofSafetyAnalysisReportsforNuclearPowerPlants,LWREdition,"

BranchTechnical Position-MTEB5-2,FractureToughness Requirements, Section5.3.2,USNRC,Washington, DC,1981.NUREG/CR-5265, "SizeEffectsonJ-RCurvesforA302-BPlate,"A.L.HiserandJ.B.Terrell,USNRC,Washington, DC,1989.Memorandum, A.L.HiserandS.N.M.HalikofUSNRCtoK.R.Wichman,USNRC,"J-RCurvesforLowToughness A302BPlate,"USNRC,September 9,1993.

12[13]NED0-32205,

".10CFR50 AppendixGEquivalent HarginAnalysisforLow'pperShelfEnergyinBWR/2ThroughBWR/6Vessels,"

Licensing TopicalReportfortheBWROwners'roup, GENuclearEnergy,April,1993.[14]Westinghouse ElectricComputerAnalysis(WECAN)Code,File87-1J7-WESAD-Rl, datedDecember1987.[15]Bloom,J.H.andD.R.Lee,"UsersGuidefortheFailureAssessment DiagramComputerCodeFAD,"BabcockandWilcox,Rev.4,April1990.[16]Conference Call,NRC,CarolinaPowerELightandWestinghouse, December13,1993.[17]LetterfromD.B.Waters,CarolinaPower5LightCompanytoUSNRC,ofDecember21,1993,"Carolina Power5.LightCompany,H.B.RobinsonSteamElectricPlant-UnitNo.2,DocketNo.50-261/License No.DPR-23,ReactorVesselUpperShelfEnergyForReactorVesselCoreRegionPlateHaterials."

[18]LetterfromE.E.Fitzpatrick, IndianaHichiganPowertoT.E.Hurley,USNRC,AEP:NRC:11738,withAttachment

entitled, "American ElectricPowerServiceCorporation, DonaldC.CookNuclearPlantUnit2,UpperShelfCharpyValues,"January24,1994.

13TABLE3J<.~vs.J,forLevelsA5.BfromMCAP13587,Revision1,(PnhsonJare>n-lbs/in

)CASE2Loo384APPLIEDdJda318702MATERIALdJda2925METCRITERIA?

Yes3Loo4LooPlant7Plant17500590525548321345222197585527614527614214059923305992330YesYesYesYes()-Calculations basedonJ-RCurvesfromReference 11TABLE4J~.~vs.J<,forLe~elCfromMCAP13587,Revision1(PnhsonJaresn-lbs/in

)CASE2Loo311APPLIEDdJ/da225702MATERIALdJ/da2925METCRITERIA?

Yes3Loo4LooPlant7Plant17310311308319252225250240585527614527614214059923305992330YesYesYesYes()-Calculations basedonJ-RCurvesfromReference ll 14TABLE5J<,.~vs.J,,forLevelDfromWCAP13587,Revision1(Pn>tsonJare1n-lbs/in

)CASE2Loo3Loo4LooPlant7Plant17APPLIEDdJda447447468MATERIALdJda2925214059923305992330METCRITERIA?YesYesYesYesYes()-Calculations basedonJ-RCurvesfromReference ll