ML17228B235

Fm Analysis of St Lucie Pressurizer Instrument Nozzle.

ML17228B235
Person / Time
Site:	Saint Lucie
Issue date:	07/11/1995
From:	NANA A D, YOON K K BABCOCK & WILCOX CO.
To:
Shared Package
ML17228B236	List: L-95-220, Forwards Suppl to ISI Plan Second ten-yr Interval Revised Stress & Fracture Mechanics Evaluations Pressurizer Instrument Nozzles ML17228B235 ML17228B237
References
32-1235128-02, 32-1235128-2, NUDOCS 9508100179
Download: ML17228B235 (35)

Text

BNT-20697-2(11/B9)(BNHP.20697.1)IljBBMINUCI.EAR%MSERll!CECOMPANYCALCULATION"SUMMARYSHEET(CSS)DOCUHENTIDENTIFIER32-1235128-02FMAna1sisofStLuciePressurizerInstrumentNozz1ePREPAREDBY:AshokD.NanaCOSTCENTER41020REFTPAGE(S)SIGNATURETITLEPrincialEnineerREVIENEOBY:KennethK.Yoon'IGNATURE/A/01$7//F95TTTRETechnicalnenltant01$7II'HSTATEHENT:REVIENERINDEPENDENCEPURPOSEANDSUHHARYOFRESULTS:PurposeToprovideaboundingflawevaluationforthesix1"instrumentnozzleslocatedinthesphericalheadsofthepressurizer.Theevaluationwillconsideraconservativeflawsizeandwilldeterminetheacceptabilityofthepostulatedboundingflawforthefortyyeardesignlifeoftheplant(30futureyears).ThisflawevaluationwillbeperformedinaccordancewithIWB-3612ofSectionXI,ASMEBoilerandPressureVesselCode.SummaryofResultsThepostulatedflawsizeof0.875inchesintheinstrumentnozzles(6)ofthesphericalheadsoftheSt.LucieUnit2pressurizerwasfoundtobeacceptableforthedesignlifeoftheplant,perIWB-3612oftheASMECodeSectionXI.***BWNTNON-PROPRIETARY***THEFOLLOJINGCOHPUTERCODESHAVEBEENUSEDINTNISDOCUMENT:CODE/VERSION/REVCODE/VERSION/REVTHISDOCUHENTCONTAINSASSUHPTIONSTHATHUSTBEVERIFIEDPRIORTOUSEONSAFETY-RELATEDIIORK"-'P508100179-950802PDRADOCK050003899PDRYES()NO(X)PAGE1GF29 B&WNuclearTechnologies1***BWNTNON-PROPRIETARY***32-1235128-02RECORDOFREVISIONSRevision000102DescritionofRevisionOriginalReleaseIssueof"Non-Proprietary"VersionRe-analysisconsideringonlytheinstrumentnozzles(6)locatedinthesphericalheadsand.usingfracturetoughnessvalueof200ksiVinDateReleased12/947/95Preparedby:A.D.NanaReviewedby:K.K.YoonD:~JI995D':~JI1995Page2of29 BA&NuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02TABLEOFCONTENTSPageEXECUTIVESUMMARY

1.0INTRODUCTION

1.1Assumptions2.0DESIGNINPUTS~~~~I73.0GEOMETRY,FLAWSIZEANDORIENTATION..........3.1GeometryofBoundingPressurizerNozzlePenetration...3.2FlawSizeandOrientation.......94.0MATERIALTOUGHNESS...135.0LOADINGCONDITIONS/STRESSES~~5.1NormalandUpsetLoadingConditions~~~~~~0~~~~14~~~~~~~~145.2EmergencyandFaultedLoadingConditions...........166.0FLAWEVALUATION.....................'.~..'...............176.1FlawEvaluationforNormalandUpsetLoadingConditionLoads6.2FlawEvaluationforEmergencyandFaultedConditionLoads.....182

07.0CONCLUSION

S278.0REFERENCES28Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page3of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02EXECUTIVESUMMARYDuringthe1994refuelingoutageexternalleakagewasidentifiedatthepressurizerinstrumentnozzle"C"ofFloridaPower&LightCompany'sSt.LucieUnit2.SubsequentNDEidentifiedindicationsontheJ-weldsforthreeoffoursteamspaceinstrumentnozzles.Modificationsweremadeandjustificationsperforinedtodeterminethepotentialforcrackgrowthduringplantoperation.Theevaluationperformedatthetimewasconservativelylimitedtoonefuelcycle.ThepurposeofthisevaluationwastojustifyacceptabilityofindicationsintheJ-weldforthesix1"instrumentnozzlesinthepressurizerfor30futureyearsofplantlife.Thesixnozzlesarelocatedinvariousregionsofthepressurizerandarehorizontallyandverticallyoriented.Fouroftheinstrumentnozzlesarehorizotallyorientedandcontainedinthepressurizerheadsteam-spaceregion.Theremainingtwonozzlesareverticallyorientedandlocatedinthelowerheadofthepressurizer.Adetailedfiniteelementstressanalysiswasperformedthataccountedforallsixnozzlepenetrationregions.Thestressanalysisconsideredandevaluatedallsignificantdesigntransientsintheevaluation.Themostsignificanttransientproducedmaximumtensilestressesintheinsideofthepressurizershellatthenozzlepenetrationregion(J-weldlocation)~Forthenormalandupsetconditioncategory,themaximumtensilestress(hoop)wasdevelopedduringanupsetconditionreactortriptransient(lossofloadtransient).Thistransientwasconservativelyevaluatedfor375cyclestoboundallfuturecyclesofplantheatup/cooldown.Fortheemergencyandfaultedcondition,thelossofsecondarypressuretransientwasevaluatedsincethesignificantcooldownduringthistransientproducedmaximumtensilestressesattheJ-weldlocation.Thefracturemechanicsanalysispostulatedanozzlecornerflawwithaconservativeflawsizeanddetermineditsacceptabilityforthirtyfutureyearsofplantlife.Anozzlecornerflawwithaninitialflawsizeof0.875incheswaspostulatedintheanalysis.Theflawsizeisconsideredtoboundthestructuralandbutteringwelddeptharoundthenozzlearea.AfatigueflawgrowthPreparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page4of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02analysiswasperformedforthenormalandupsetconditionloads.Consideringalltheapplicabledesigntransients,theinitialpostulatedflawsizeof0.875inchesintheinstrumentnozzleoftheSt.Luciepressurizerwasdeterminedtoreachafinalflawsize(af)of0.966inchesattheendofthedesignlifeoftheplant.Themaximumappliedstressintensityfactoratthefinalflawsizeis46.42ksiVinandresultsinasafetyfactorof4.31.Thissafetyfactorisgreaterthantherequiredsafetyfactorof410(3.16)perIWB-3612(a)ofASMECodeSectionXI.Fortheemergencyandfaultedcondition,themaximumappliedstressintensityfactoratthefinalflawsizeis84.6ksiVinandresultsinasafetyfactorof2.36.ThissafetyfactorisgreaterthantherequiredsafetyfactorofV2(1.414)perIWB-3612(b)ofASMECodeSectionXI.Therefore,itisconcludedthatthepostulatedflawsizeintheinstrumentnozzleoftheSt.Luciepressurizerisacceptableforthedesignlifeoftheplant(thirtyfutureyears)perIWB-3612oftheASMECodeSectionXI.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page5of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-0

21.0INTRODUCTION

Thepurposeofthisanalysisistoprovideaboundingflawevaluation.forsixoftheseveninstrument/temperature1"nozzlesinthepressurizer.Allthesixnozzlesarelocatedinthesphericalheadsofthepressurizer.Theevaluationwillconsideraconservativeflawsizeandwilldeterminetheacceptabilityofthepostulatedboundingflawforthirtyfutureyearsofplantlife.ThisflawevaluationwillbeperformedinaccordancewithIWB-3612ofSectionXI,ASMEBoilerandPressureVesselCode.1.1Assumptionsa.Anozzlecornerflawwithaninitialfiawsizeof0.875inchispostulated'nthisanalysis.Thisflawsizeisconsideredtoboundthestructuralandbutteringwelddeptharoundthenozzlearea.b.ItisassumedthatthepostulatedflawcoverstheentireSMAWI-182weldregionsothatprimarywaterstresscorrosioncracking(PWSCC)isnolongeractiveforthepressurizer.c.Threehundredandseventyfivefuturecyclesofheatup/cooldownareconservativelyassumedfortheremainingdesignlifeoftheplant.d.Eightfuturecyclesofpressuretestsat10%oftheoperatingpressure(2475psia)areassumedoverthenext30years.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page6of29 BAWNuclearTechnologiesI***BWNTNON-PROPRIETARY***32-1235128-022.0DESIGNINPUTSa)GeometryofPressurizerNozzlePenetrationsThepenetrationconfigurationofthepressurizerupperheadsteamspaceinstrumentnozzles(four)withthemodifiednozzledesigniscontainedinDrawing2998-19321ofReference1.Thepenetrationconfigurationofthepressurizerbottomhead(two)instrumentnozzlesiscontainedinDrawing2998-18709ofReference2.minimumpressurizerheadthickness=3.875inb)DesignTransients/NumberofCyclesThefollowinginformationwastakenfromReference3,withthetransientspecificinformationfromReference4(forthefortyyeardesignlifeoftheplant).i)500cyclesofnormalheatup/cooldownforthedesignlifeofthecomponent.ThenormaloperatingpressureperTable5.4-6ofReference3is2250psia.ii)Atotalof480cyclesofupsetconditiontransients.Themaximumpressurerangeduringupsetconditiontransientis660psiandoccursbetween2400psia(abnormallossofturbinegeneratorload)and1740psia(reactortriptransient)withassociatedtemperaturedifferenceof50'Fduringlossofloadtransient(Reference4).iii)200cyclesofleaktestat2250psia(Reference4)iv)Theremainderofthenormaloperatingtransientsi.e.15,000cyclesofpowerchangecyclesfrom15%to100%power,2,000cyclesofsteppowerchangesof10%ofthefullloadand1x10'yclesofnormalvariationsof100psiandtemperaturedifferencesoflessthan20'F(Reference4).v)5cyclesofemergencyconditiontransient(completelossofsecondarypressuretransient),giveninReference4.Sincetheanalysiswasperformedfor30futureyears,only75%oftheabovenumberofcyclesforagiventransientwereconsideredintheevaluation.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page7of29

BAWNuclearTechnologiesI***BWNTNON-PROPRIETARY***32-1235128-02c)MaterialsThepressurizerheadandshellmaterialismadeofSA-533GradeBClass1perReference1andAddendum2ofReference4.PerTable5.2-9ofReference5,theRTpyofthepressurizershellmaterialis10'F.d)ApplicableASMESectionXICodePerReference6,theapplicableASMESectionXIcodeis1989Edition.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page8of29 7I B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-023.0GEOMETRY,FLAWSIZEANDORIENTATION3.1GeometryofBoundingPressurizerNozzlePenetrationTherearesix1"instrumentnozzlesinthepressurizerofSt.LucieUnit2asdepictedbythedrawingofReference2.Fouroftheinstrumentnozzlearecontainedinthepressurizerupperheadsteamspaceregion.ThesenozzlesarehorizontallyorientedinthelowersphericalpartoftheupperheadasillustratedinFigure1.TheremainingtwoinstrumentnozzlesarelocatedinthelowerregionofthepressurizerasillustratedinFigure2.Thesenozzlesareverticallyorientedandlocatedinthelowerheadofthepressurizer.Theminimumwallthicknessoftheupperandthelowersphericalheadsis3.875inches.ThestressanalysisofReference7tookeachofthesixnozzlepenetrationregionsinthesphericalheadsintoconsiderationandconstructedanozzlepenetrationfiniteelementmodeltoboundallsixinstrumentnozzlelocations.ForadditionaldetailsrefertoSection3.3ofReference7.3.2FlawSizeandOrientationItispostulatedthatthereexistsanozzlecornerflaw(asdepictedinFigure3)withaninitialdepthequaltothestructuralandbutteringwelddeptharoundthenozzlearea.Therefore,aflawsizeof0.875inchesisassumed.Theorientationofthisflawwasassumedtobeinthex,yplane(seeFigure3)whichisnormaltothehoopdirection.ThisistheworsecaseflaworientationsincethemaximumstressisprimarilyduetopressureinducedhoopstressascanbeseenfromtheresultsofthestressesalongtheflawplaneinSection6.0ofReference7.Theanalysiswillevaluatemaximumstressintensityfactorandperformfatigueflawgrowthanalysisbasedonconsiderationofallcrackfrontanglesi.e.from6equalto0degrees(vesselside)tothe45degreeflawplaneto90degrees(nozzleboreside).Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page9of29

~B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02Figure1:UpperPressurizerRegionUlQvZIEhr~~~mm>r4gP>>/gxmSE'he.R.(65C~Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page10of29 IIII~~I~~~~IPEI~'~.~I'~~~~~.~.~~~~~~

B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02Figure3:NozzleCornerFlawQpter)n/RLNozzt.6PgasSua<<~~HGRbe-'/IPOSg~gAl6'DNozzleCoRNEP,FLAWZhl$7gUPTON!4Thlozz~E.C,Io.ld~wgx,ycoordinatesintheplaneofthecrack845degreesPreparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page12of29 BdkWNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-024.0MATERIALTOUGHNESSThepressurizershellandheadisSA-533,gradeB,class1perReference1andAddendum2ofReference4.TheRT>>ofthismaterialis10'F.AccordingtoIWB-3612,thearresttoughnesscurve,KI,inAppendixA,SectionXIofASMEBoiler&PressureVesselCode(Reference6)wasusedforthisevaluation.SincetheRTN>>ofthepressurizeris10'F,thematerialisconsideredtobeattheuppershelfregionfortemperaturesabove192'F.Becausethemaximumstressisprimarilyduetopressure,thecorrespondingtemperaturesduringthetransientwhenthemaximumstressesoccurinthepressurizershell/headareabove500'F.Anuppershelfvalueof200ksiVinwasconservativelyusedintheanalysis.Itisnotedthatanyshiftduetoirradiationisnegligible,i.e.nochangesinRT>>valueofthepressurizerwithincreasesinEffectiveFullPowerYears(EFPYs').Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page13of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-025.0LOADINGCONDITIONS/STRESSES5.1NormalandUpsetLoadingConditionsThestressesduetonormalandupsetconditionsarecontainedinSection6.0ofReference7.Thecompositetransientevaluatedintheanalysisconsistedof100'F/hrheatup,100%powersteadystatecondition,aboundingupsetconditiontransient(representedasa53'Fstep-downtopressureof1740psiaanda53'Fstepupwithapressureof2400psia)anda200'F/hrcooldownrateasdescribedinSection5.0ofReference7.ThenormalandupsetconditiontransientcasesaresummarizedinTable1.TheresultsoftheanalysisinReference7showedthatthemaximumstressesoccurduringanupsetconditionstepdowntransient(transientcase2casgiveninTable1).Thenextlargeststressstateoccursduringsteadystateconditionswhenthepressureis2400psia(transientcase2a).Thesemaximumstressstatesoccursattemperatureswellabove500'Fwhenthematerialisatupper-shelf.Transientcase2cwasconservativelyevaluatedfor375cycles(fromaninitialstress-freestatetothemaximumupsetcondition),inSection6.1,toboundthe360cyclesassociatedwithalltheupsetconditiontransientsaswellasthe375cyclesofplantstartupandshutdownand150cyclesofleaktests.Inaddition,8cyclesofpressuretests(case3,Table1)wereevaluated.Duringnormalcooldownthemaximumstressoccursat595'F(transientcase1casgiveninTable1)whenthematerialisatupper-shelf.Toensurethatthefracturetoughnessmargin(factorofsafetyos10perIWB-3612)ismaintained,throughouttheentirecooldowntransient,thetimeattheendofthe200'F/hrcooldownisalsoevaluated(transientcase1dasgiveninTable1).Atthistime,thebulkfluidtemperatureisat70'Fandmaximumthermalstressesaredevelopedinthepressurizershell/head.Also,thefracturetoughnessislow.However,thecomponentisdepressurizedsothattheresultingstressesarenotsignificantascanbeseeninSection6.0ofReference7forthistransientcase.Adequatefracturetoughnessmarginduringtheentireheatup/cooldownwasdemonstratedinSection6.1.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page14of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02Table1:NormalandUpsetConditionTransientCasesTransientCategory,CaseNormal,laNormal,lbNormal,lcNormal,ldDescriptionofTransientTimeEndof100'F/hrheatup(max.stressduringheatup)100%powersteadystateCooldownat560'F(max.stressduringcooldown)Cooldownat70'F(max.thermalstressduringcooldown)Pressure(psia)225022501472Temperature('F)65365359570NumberofCycles'75Normal,lePressureandtemperaturefluctuationsduringoperationd,P5100b,T<20765,000Upset,2aUpset,2bUpset,2cTest,3Atmax.pressure(lossofturbinegeneratorload)53'Fstepup53'Fstepdown110%ofoperatingpressure2400240017402475653600-653653-6006533604Associatedwith30futureyearsofplantlife.Basedonconsidering75%ofthedesigncyclesgiveninReferences3and4.ThiscaseisnotspecificallyevaluatedinReference7.Conservativelyassumedtobeone-halfthestressesduetothetransientcases2band2c.11,250cyclesofplantloading/unloading,1,500cyclesof10%steploadincrease/decreaseand750,000cyclesofnormalpressurevariationareconservativelygroupedbythistransientcase.Thereareonly30cyclesoflossofturbinegeneratorload,however,300cyclesofreactortriptransientand30cyclesoflossofprimaryflowtransientareconservativelygroupedbythistransientcase.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page15of29 BOWNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02Inadditiontothe375cyclesofplantstartup/shutdown(includes360cyclesofupsetconditiontransients)and8cyclesofpressureteststhereare11,250cyclesofplantloading/unloading,1,500cyclesof10%steploadincrease/decreaseand750,000cyclesofnormalpressurevariation(+/-100psi,+/-7'F)asgiveninReferences3and4.Reviewofthesetransientsshowthatthesetransientscanbegroupedasasingletransientwith765,000associatedcyclesofmaximumpressurevariationof100psiandtemperaturevariationoflessthan20'F(transientcaseleasdefinedinTable1).TheassociatedstressrangeduetothistransientisgiveninTables6-14and6-15ofReference7.5.2EmergencyandFaultedLoadingConditionsTheonlyemergencyandfaultedconditiondesigntransient(pressurizerpressureandtemperatureversustime)providedinReferences3and4isthelossofsecondarypressuretransient(anemergencyconditiontransient).ThefaultedconditiontransientsdescribedinReferenc'es3and4are;i)thoseduetosafeshutdownearthquakewithnormaloperationatfullpowerandwithandwithoutpiperuptureconditionandii)thoseduetoLOCA.However,perTable3.9-3BofReference3,therearenoassociatedcyclesforthefaultedconditiontransients.Therefore,theonlytransientevaluated(in.Reference7)forthisloadingconditionisthelossofsecondarypressuretransient.Duringthistransientthepressurizerexperiencesasignificantcooldownrate.Asaresultofthiscooldownrate,hightensilestressesattheinsidesurfaceofthenozzlecornerregioncanbeproduced.ThisisreflectedinthestressresultsgiveninSection6.0ofReference7whichproducedthemaximumhoopsurfacestressamongstallthetransientsanalyzed.ThistransientcasewillbeevaluatedinSection6.2.Thereare4cyclesassociatedwiththistransientcase.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page16of29 B&WNuclearTechnologies**".BWNTNON-PROPRIETARY***32-1235128-026.0FLAWEVALUATIONAthreedimensionalnozzlecornercrackispostulatedforthisanalysis.Thestressintensityfactor,KforthisflawgeometryisgiveninReference8andreportedbelow:K,=~iia[0.706A+0.537(2a/m)A,+OA48(a/2)A+0.393(4a/3n)A]whereAAAandA,arethepolynomialcoefficientsofthestressprofileexpressedas:o(r)=+A,r+A~r+A,r'hethreedimensionalnozzlecornerflawsolutiongivenaboveisutilizedtoevaluatethepostulatedflawintheoneinchpressurizerinstrument/temperaturenozzlesofSt.Lucieunit2.Thesolutiongivenaboveisapplicableforthe45degreeflawplaneasillustratedinFigure3.Hence,thestressesareobtainedalongthisflawplaneasillustratedinFigure6.2ofReference7.Toaddressthestressintensityfactorsatothercrackfrontangles,theinformationcontainedinReference9isutilized.Reference9hasevaluatedthestressintensityfactorsduetopressureinducedhoopstressesinanozzlecornerwithaquartercircularcrackgeometry.Threenozzlecornerflawsizeswithflawsizetothicknessratiosof0.15,0.26and0.34wereinvestigatedinthisstudy.Thisstudyprovidedthenon-dimensionalstressintensityfactorsasafunctionofthecrackfrontangle,eforeachofthethreeflawsizesasillustratedinFigure11ofReference9.Fromthisfigureitisclearthatthestressintensityfactornearthesurfacesofboththevesselandthenozzleboresideisslightlygreaterthanthestressintensityfactoralongthe45degreeplane.Forthetwolargerflawsizes(flawsizetothicknessratiocomparabletothisevaluation),thestressintensityfactornearthesurfacesisabout5to10percenthigherthanalongthe45degreeplane.Therefore,todeterminemaximumflawgrowthwithconsiderationofallcrackfrontangles,thestressintensityfactorsobtainedusingtheaboveequationswillbeincreasedby10percent.Thisisaconservativepractice.Aninitialflawdepthof0.875inchesisassumedtoboundthestructuralandbutteringwelddeptharoundthenozzlearea(J-welds).Thepostulatedflawintheinstrumentnozzleisevaluatedfornormal/upsetconditionandemergency/faultedconditionasgivenbelow.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page17of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02r6.1FlawEvaluationforNormalandUpsetLoadingConditionLoadsAsdiscussedinSection5.1,thefollowingboundingtransientcasewasanalyzedforthenormalandupsetconditionloading.Transientcase2c(reactortriptransient)wasevaluatedfor375cycles.Themaximumtensilestressstatealongtheflawplaneoccursduringthisconditionwhenthepressurizerisassumedtocyclefromanintialstress-freestate(0psiat70'F)toareactortriptransient.Thisstressstatewillbeconservativelyassumedtooccurforall375cyclesofnormalheatup/cooldown.Asafirststep,athirdorderpolynomialequationtothestressesfromthefiniteelementanalysisresultswasmade.Thecoefficientsforthepolynomialequationwereobtainedusingaleastsquareflit.Theresultingstressesusingthepolynomialequationagreeverywellwiththefiniteelementmodel(FEM)stressesasillustratedinFigure4.TheFEMstressesareforthemaximumupsetconditionpressurestressat2400psiaasgiveninTable6.4ofReference7.Thestressintensityfactor,Kfortheinitialflawsizeof0.875inchesis:K,(a;)=44.89ksiVinAfatigueflawgrowthanalysiswasperformedfor375cyclesusingtheabovemaximumupsetconditionstressesasgiveninTable2a.Thefatiguecrackgrowthrateis:da/dN=C,(b,K,)"whereda/dNisthecrackgrowthrateinmicro-inchpercycle,b,K,isthemaximumK,minusminimumK,(inthiscasetheminimumK,iszero),C,andnarematerialconstantsandareobtainedfromthefatiguecrackgrowthratecurvewhichisgiveninFigureA-4300-1ofReference6.Fromthisfigure,itcanbeseenthatforasurfaceflaw(waterreactorenvironment)withanRratio50.25andb,K,219ksiVin,theapplicablematerialconstantsareC,=1.01x10'in/cycleandn=1.95.Theflawsizeattheendof375cycles,is0.94inchesandthemaximumappliedK,=46.00ksiVin.Also,8cyclesofpressuretestsat2475psiawerePreparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page18of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02Figure4:FEMthroughwallstressesversuspolynomialfitstresses45000ForUpsetConditionStepDoomTransientFEMstressesPolyriomial-Fit-stresses--3500030000COD.00250001500000.51.5Distance(s),along45degreeflawplanePreparedby:A.D.NanaReviewedby:K.K.YoonDate:Jurie1995Date:June1995Page19of29 1

BAWNuclearTechnologies***BWNTNON-PROPRIETARY***.32-1235128-02consideredintheanalysis.Theflawsizeattheendof8cyclesofpressuretests,is0.942incheswithamaximumappliedK,=43.26ksiVin.Inaddition,thereare765,000cyclesofpressureandtemperaturevariations(transientcaseleofTable1).TheRratio(K,;JK,~forthiscaseis0.92andsinceb,K,islessthan2.9ksiVin,theapplicablematerialconstantsareC,=1.2x10"in/cycleandn=5.95.Thefatigueflawgrowthdueto765,000cyclesoftheabovetransientiscomputedusingtheflawsizeafter375cyclesofheatup/cooldownand8cyclesofpressuretests(0.942inches)astheinitialflawsize.TheresultsaregiveninTable2bwhichshowsthatafterconsiderationof765,000cyclestheflawsizeis0.964inches.Inaddition,afterconsiderationof4cyclesoflossofsecondarypressuretransientasgiveninTable4thefinalflawsize(af)is0.966inches.Themaximumappliedstressintensityfactoratthefinalflawsizeis:K,(af)=46.42ksiVin.Sincetheuppershelftoughnessis200ksiVin,thisresultsinasafetyfactorof4.31(asgiveninTable3)whichisgreaterthantherequiredsafetyfactorofv10(3.16)perIWB-3612(a)ofReference6.Also,asdiscussedinSection5.1,toensurethatthefracturetoughnessmarginismaintained,throughtheentirecooldowntransient,thetimeattheendofthe200'F/hrcooldownisevaluated(transientcase1dofTable1).ThemaximumappliedK,attheendofcooldown(70'F)wasdeterminedtobe8.69ksiVin.Theassociatedfracturetoughness,K,~,wasobtainedfromtheequationgivenonPageC-18ofReference8.Usingthisequation,thefracturetoughnessat(TRTNpr)=70'F-10'For60'Fis56.5ksiVin.Therefore,thereisasafetyfactorof6.50forthisconditionwhichissignificantlygreaterthantherequiredsafetyfactorofV'10perIWB-3612(a)ofReference6.6.2FlawEvaluationforEmergencyandFaultedConditionLoadsAsdiscussedinSection5.2,theonlyemergencyandfaultedconditiontransientrequiringevaluationisthelossofsecondarypressuretransientwhichhas4cyclesassociatedwithit.TheresultsoftheanalysisareprovidedinTable4.Thistransientoccursfollowingasteadystatecondition.Thed,K,associatedwiththistransientis44.84ksiVin.TheflawgrowthassociatedPreparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page20of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02withthistransientis2mils.Themaximumappliedstressintensityfactoratthefinalflawsize(a,)of0.966inchesfortheemergencyandfaultedconditionis:K~(a,)=84.6ksiVin.AspreviouslynotedinSection5.2,thematerialremainsatuppershelfduringthistransient(K<<=200ksiVin).Therefore,thisresultsinasafetyfactorof2.36fortheemergencyandfaultedconditionwhichisgreaterthantherequiredsafetyfactorofV'2perIWB-3612(b)ofReference6.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page21of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02Table2a:FatigueFlawGrowthAnalysisfor375cyclesofnormalheatup/cooldownFatigueFlawGrowthAnalysisofPostulatedNozzleCornerCrackai0.875inincrement=0.005inGEOMETRICFACTORSGO=1.251G1=0.606G2~0.397G3~0.296FordK>STRESSAOA1A2A3FACTORS40.21-12.22-1.531.26dN=C1m=R=Kmin=Kmax=KI=GO*AO*a(1/2)+G1*A1*a"(3/2)+G2*A2+a"(5/2)+G3*A3*a(7/2)Factorforworsecaseflawangle=1.119ksidin375cycles1.01E-07in/cycle1.9500.00ksi*in"0.544.98ksi*in"0.5KIA=Safetyfactor=200ksi*in"0.53'6ai(in)aj(in)FatigueGroup1KI(~a)C1(dKI)"mdNksidinin/cyclecyclesTotaldNcyclesCheckKIA/KIAccept70.8750.8800.8850.8900.8950.9000.9050.9100.9150.9200.9250.9300.9350.8750.8800.8850.8900.8950.9000.9050.9100.9150.9200.9250.9300.9350.9400.9544.8944.9845.0745.1545.2445.3345.4145.5045.5845.6745.7545.8445.9246.0046.161.69E-041.70E-041.70E-041.71E-041.71E"041.72E-041.73E-041.73E-041.74E-041.75E"041.75E-041.76E-041.76E-041.78E-0429.629.529.429.329.229.028.928.828.728.628.528.428.329.659.188.5117.7146.9175.9204.9233.7262.4291.1319.6348.0376.4continuecontinuecontinuecontinuecontinuecontinuecontinuecontinuecontinuecontinuecontinuecontinuestop4.454'44.434.424.414.404.404.394.384.374.364.364.354.33OKOKOKOKOKOKOKOKOKOKOKOKOKOKPreparedby:A.D.NanaDn'ltl&'l%>DrlhvKK'OOnDate:June1995Date;June1995Page22of29 BOWNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02Table2b:FatigueFlawGrowthAnalysis(cont'd)forremainingnormaloperatingtransientsFor8cyclesofpressuretestsat110%-ofoperatingpressureor2475psigStressFactorsfor2400psiareratioedby(2475/2400)1.031STRESSFACTORSFordK>19ksi~inAO=34.00dN=8Al-1.98Cl~1.01E-07A2-3.51m1.95A31.37R0Kmin=0.00Kmax43.24KZ=Go*AO*a"(1/2)+G1*A1*a"(3/2)+G2*A2+a"(5/2)+G3*A3*a"(7/2)Factorforworsecaseflawangle=1.1increment0.001inai(in)aj(in)FatigueGroup2KE(aj)C1(dKE)"mdNksiginin/cyclecyclesTotaldNCheckcyclesKlA/KXAccept70.9400.9410.9410.94243.2443.261.56E-041.57E-046.396.396.4continue12.8stop4.634.62OKOKPreparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page23of29 8'NuclearTechnologies***BWNTNON-PROPRIA<TARY***32-1235128-02Table2b:FatigueFlawGrowthAnalysis(cont'd)forremainingnormaloperatingtransientsFor765,000cyclesofremainingnormalconditiontransientsGOGlG2G31.2510.6060.3970.296GEOMETRICFACTORSSTRESSAOAlA2A3FACTORSGroup132.54<<12.426.41-1.17-Group242.80-26.4213.41-2.70dN=Cl7650001.20E-115.95andR>0.650.92FordK<19ksiginKI~GO*AO*a"(1/2)+Gl*A1*a(3/2)+G2*A2*a(5/2)+G3*A3*a(7/2)Factorforflawangle~increment0.002in1.1Kmin=43.88ksi*in"0.5Stepuptransient-Kmax=47.95ksi*in"0.5StepdowntransientFactor=0.5ai(in)aj(in)Group1MinKI(aj)ksi<finnFatigueGroup3Group2MaxKI(aj)ksiJinDeltadKI(aj)Cl(dKI)"Mksiginin/cycledNcyclesTotaldNcyclesCheck0.9420.9440.9460.9480.9500.9520.9540.9560.9580.9600.9620.9440.9460.9480.9500.9520.9540.9560.9580.9600.9620.96438.0438.0738.1138.1438.1738.2038.2338.2738.3038.3338.3645.4445.4745.5045.5345.5645.5945.6245.6545.6845.7145.743.703.703.703.703.703.693.693.693.693.693.692.88E-OB2.87E-OB2.87E-OB2.87E-OB2.86E-OB2.86E-OB2.85E-OB2.85E-OB2.85E-OB2.84E-OB2.84E-OB69502.069596.269691.469787.769885.069983.370082.770183.070284.470386.970490.369502.0continue139098.1continue208789.6continue278577.3continue348462.2continue418445.6continue488528.2continue558711.2continue628995.7continue699382.5continue769872.8stopPreparedby:A.D.NanaPsvi<w<rlhv'KYnnnDate:June1995Date:June1995Pace24of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02Table3:SummaryofflawsizesancheckwithacceptancecriteriafornormalandupsetconditionKIA200ksidinLumpedTransients:Considers375cyclesofworstupsetloads(coversfuturenormalheatupandcooldown)8cyclesof2475psigpressuretestsaswellas765,000cyclesofremainingnormalconditiontransientcyclesai(in)aj(in)KI(aj)KIA/KI(aj)ksiPinTransientGroupASMEACCEPTCODE0.8750.9350.9410.9620.8800.9400.9420.9640.96644.9846.0043.2638.2046.424.454.354.625.244.31Beginning-1endof1endof2endof3endofall3.163.163.163.163.16OKOKOKOKOKPreparedby:A.D.NanaDate:June1995Reviewedby:K.K.Yoon...Date:June19)5Page25of29

B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02Table4:SummaryofflawgrowthanalysisandcheckwithacceptancecriteriaforemergencyandfaultedconditionFor4cyclesoflossofsecondarypressuretransientGO~GlG2G3.~-1.2510.6060.3970.296GEOMETRICFACTORSAoA3STRESSFACTORSGroup130.91A1-1.80A2"3.191.25Group2101.23-113.1456.99-12.44dN~Cl41.84E-071.950.471.82FordKv15ksidinKI~GO*AO*a"(1/2)+Gl*A1*a"(3/2)+G2*A2~a"(5/2)+G3*A3*a"(7/2)Kmin=Kmax39.76ksi*in"0.5steadystateat2250psia84.60ksi+in"0.5lossofsecondarypressureFactorincrementai(in)forworsecaseflaw0.002inGroup1MinajKI(aj)(in)ksifinangleGroup2MaxKI(aj)ksiPinDeltadKI(aj)'l(dKI)"Mksi~inin/cyclecyclesTotaldNcyclesCheck0.96400.966039.7684.6044.843.06E-046.5'.5stop'SummaryoffinalflawsizesandcheckwithacceptancecriteriaKIC200ksiSinForEmergencyandFaultedCondition:ai(in)af(in)KI(af)KIC/KI(af)ksidinASMEACCEPTCODE0.96400.966084.602.361.41OKPreparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page26of29 Ol>"d B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-0

27.0CONCLUSION

SConsideringalltheapplicabledesigntransients,theinitialpostulatedflawsizeof0.875inchesintheinstrumentnozzleoftheSt.Luciepressurizerwasdeterminedtoreachafinalflawsize(a,)of0.966inchesafter30futureyearsplantlife.Forthenormalandupsetconditionthemaximumappliedstressintensityfactoratthefinalflawsizeis46.42ksiVinandresultsinasafetyfactorof4.31.Thissafetyfactorisgreaterthantherequiredsafetyfactorof410(3.16)perIWB-3612(a)ofReference6.Theanalysisconsideredallcrackfrontanglestodeterminethemaximumappliedstressintesityfactorandensureboundingfatigueflawgrowth.Fortheemergencyandfaultedcondition,themaximumappliedstressintensityfactoratthefinalflawsizeis84.6ksiVinandresultsinasafetyfactorof2.36.Thissafetyfactorisgreaterthantherequiredsafetyfactoros2perIWB-3612(b)ofReference6.Therefore,itisconcludedthatthepostulatedflawsizeintheinstrumentnozzleoftheSt.LuciepressurizerisacceptableforthethirtyfutureyearsofplantlifeperIWB-3612oftheASMECodeSectionXI.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page27of29 B&WNuclearTechnologiesI***BWNTNON-PROPRIETARY***32-1235128-028.0REFERENCES1~'loridaPower&LightDrawingNo.2998-19321,Rev.0,"TopHeadInstrumentNozzlesRepair".2.FloridaPower&LightDrawingNo.2998-18709,Rev.1,"PressurizerGeneralArrangement".3.BWNTDocument38-1210589-00,"PressurizerInstrumentNozzles,FMDesignInput,"forSt.LucieUnit2,dated11/11/94(FP&LNumberJPN-PSLP-94-603,File:PSL-100-14).4.BWNTDocument38-1210588-00,"PressurizerInstrumentNozzles,FMDesignInput,"forSt.LucieUnit2,dated11/11/94(FP&LNumberJPN-PSLP-94-631,File:PSL-100-14).5.'t.LucieUnit2UpdatedFinalSafetyAnalysisReport,throughAmendmentNo.9,datedOctober1994.6.ASMEBoilerandPressureVesselCode,SectionXI,1989Edition.7.BWNTDocument32-1235127-02,"StressesforSt.LucieUnit2,PressurizerLEFM,"byT.M.Wiger,datedJune1995.8.EPRIReportNumberNP-719-SR,"FlawEvaluationProcedures,"witherrataforsubjectreportdatedApril14,1980,preparedbyASMETaskGrouponFlawEvaluation,ElectricPowerResearchInstitute,PaloAltoCalifornia,August1978.9."SolutionofThreeDimensionalCrackProblemsusingtheBoundaryIntegralEquationMethod,"byJ.Heliot,R.LabbensandA.Pellissier-Tanon,presentedattheSecondPreparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995Date:June1995Page28of29 B&WNuclearTechnologies***BWNTNON-PROPRIETARY***32-1235128-02InternationalConferenceonNumericalMethodsinFractureMechanics,Swansea,GreatBritain,July1980.Referencesmarkedwithan"asterisk"areretrievablefromtheUtilitiesRecordSystem.AuthorizedProjectManager'sSignaturePreparedby:A.D.NanaReviewedby:K.K.YoonDate:June1995'ate:June1995Page29of29 NUCLEARENGINEERINGDEPARTMENTCoMPoNENT,SUPPoRTANDINsPEcTIoNsP.O.Box14000JUNoBEAcHgFLoRIDA33408St.LucieNuclearPowerPlantUnit2ATTACHMENTBSTRESSESFORS7;LUCIEUNIT2PRESSURIZERLEFMPreparedbyB&WNUCLEARTECHNOLOGIESForSt.LucieNuclearPowerPlant10MilesSouthofFf.PierceonA1AFt.Pierce,Florida33034NRCDocketNumber:DocumentNumber:RevisionNumber:2Date:CommercialServiceDate:August8,198350-38932-1235127-02July14,1995