ML17228B047

Nonproprietary Version of Fracture Mechanics Evaluation of St Lucie Pressurizer Instrument Nozzles.

ML17228B047
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Site:	Saint Lucie
Issue date:	02/13/1995
From:	NANA A D, YOON K K BABCOCK & WILCOX CO.
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ML17228B046	List: ML17228B045 ML17228B047 ML17228B048 ML17228B049
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32-1235128-01, 32-1235128-01-R01, 32-1235128-1, 32-1235128-1-R1, NUDOCS 9503070359
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FLORIDAPOWERANDUGHTCOMPANYNUCLEARENGINEERING DEPARTMENT P.O.Box14000JunoBeach,Florida33408St.LucieNuclearPowerPlantUnit2ATTACHMENT AFRACTUREMECHANICSEVALUATION OFST.LUCIEPRESSURIZER INSTRUMENT NOZZLESPreparedbyB&WNUCLEARSERVICECOMPANYForSt.LucieNuclearPowerPlant10MilesSouthofFt.PierceonA1AFt.Pierce,Florida33034Commercial ServiceDate:NRCDocketNumber.DocumentNumber.RevisionNumber.0August8,198350-38932-1235128-01 Date:February13,1995iI9503070359 950302PDR'ADOCK05000389PDR

,

BWNT-2D697-2 (11/B9)(BWNP-2D697-1) llfBBWNUCLEAR%MSERVICECOMPANYCALCULATION SUMMARYSHEET(CSS)DOCUHENTIDENTIFIER 32-1235128-01 FMAna1sisofStLuciePressurizer Instrument Nozz1ePREPAREDBY:AshokD.NanaREVIEWEDBY:KennethK.Yoonnave~~COSTCENTER41020REF.PAGE(S)29SIGNATURE Princia1EnineerSIGNATURE Technical CcetantTMSTATEHENT:

REVIEWERINDEPENDENCE PURPOSEANDSUHHARYOFRESULTS:Purpose,Toprovideaboundingflawevaluation forallsevenInstrument/temperature 1"nozzlesinthepressurizer.

Theevaluation willconsideraconservative flawsizeandwilldetermine theacceptability ofthepostulated boundingflawforthefortyyeardesignlifeoftheplant.Thisflawevaluation willbeperformed inaccordance withIWB-3612ofSectionXI,ASMEBoilerandPressureVesselCode.Rev.1:Purposeofthisrevisionistoissuea"non-proprietary" versionofthedocument.

SummaryofResultsThepostulated flawsizeintheinstrument/temperature nozzlesofSt.Luciewasfoundtobeacceptable forthedesignlifeoftheplant,perIWB-3612oftheASMECodeSectionXI.**BWNTNON-PROPRIETARY**

THEFOLLOWING COHPUTERCODESHAVEBEENUSEDINTHISDOCUHENT:

CODE/VERSION/REVCODE/VERSION/REVTHISDOCUHENTCONTAINSASSUHPTIONS THATHUSTBEVERIFIEDPRIORTOUSEONSAFETY-RELATED WORKYES()NO(X)PAGE"OF30 B&WNuclearTechnologies

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• • • 32-1235128-01 RECORDOFREVISIONS Revision0001DescritionofRevisionOriginalReleaseIssueof"Non-Proprietary" VersionDateReleased12/942/95Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page2of30 B&WNuclearTechnologies

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• • • 32-1235128-01 TABLEOFCONTENTSPageEXECUTIVE SUMMARY~~~~~~~~~~~~~~~~

41.0INTRODUCTION

.........................................

~..61.1Assumptions

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~a62.0DESIGNINPUTS~~~~~~~0~~~~~~~~~~~~~~~~~~~~~073.0GEOMETRY, FLAWSIZEANDORIENTATION...................

~..93.1GeometryofBoundingPressurizer NozzlePenetration...............

93.2FlawSizeandOrientation

.....~~~~~~~~~~~~~94.0MATERIALTOUGHNESS

.................

~..~~~~~~~~~~~135.0LOADINGCONDITIONS/STRESSES

.............................

145.1NormalandUpsetLoadingConditions

........................

145.2Emergency andFaultedLoadingConditions.....................

166.0FLAWEVALUATION...........,,

.~~.................

~176.1FlawEvaluation forNormalandUpsetLoadingCondition Loads..~~~.186.2FlawEvaluation forEmergency andFaultedCondition Loads...~...,.2

27.0CONCLUSION

S

~~~~~~~~~~~~~~~~~~~~~~2

88.0REFERENCES

~~~~~~~~~~~~~~~~~~~~~29Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page3of30 B&WNuclearTechnologies

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• • • 32-1235128-01 EXECUTIVE SUMMARYDuringthe1994refueling outageexternalleakagewasidentified atthepressurizer instrument nozzle"C"ofFloridaPower&LightCompany's St.LucieUnit2.Subsequent NDEidentified indications ontheJ-weldsforthreeoffoursteamspaceinstrument nozzles.Modifications weremadeandjustifications performed todetermine thepotential forcrackgrowthduringplantoperation.

Theevaluation performed atthetimewasconservatively limitedtoonefuelcycle.Thepurposeofthisevaluation wastojustifyacceptability ofindications intheJ-weldforallseven1"'(instrument/temperature) nozzlesinthepressurizer for30futureyearsofplantlife.Thetsevennozzlesarelocatedinvariousregionsofthepressurizer andarehorizontally andvertically oriented.

Fouroftheinstrument nozzlesarecontained inthepressurizer headsteam-space region.Theremaining threenozzlesarelocatedinthelowerregionofthepressurizer.

Adetailedfiniteelementstressanalysiswasperformed thataccounted forallsevennozzlepenetration regions.Thestressanalysisconsidered andevaluated allsignificant designtransients intheevaluation.

Themostsignificant transient producedmaximumtensilestressesintheinsideofthepressurizer shellatthenozzlepenetration region(J-weldlocation).

Forthenormalandupsetcondition

category, themaximumtensilestress(hoop)wasdeveloped whenthemaximumpressureof2400psiaisreachedduringanupsetcondition transient (abnormal lossofloadtransient).

Thistransient wasconservatively evaluated for375cyclestoboundallfuturecyclesofplantheatup/cooldown.

Fortheemergency andfaultedcondition, thelossofsecondary pressuretransient wasevaluated sincethesignificant cooldownduringthistransient producedmaximumtensilestressesattheJ-weldlocation.

Thefracturemechanics analysispostulated aconservative flawsizeanddetermined itsacceptability forthirtyfutureyearsofplantlife.Afatigueflawgrowthanalysiswasperformed forthenormalandupsetcondition loads.Considering alltheapplicable designtransients, theinitialpostulated flawsizeintheinstrument/temperature nozzleoftheSt.Luciepressurizer wasPreparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page4of30 BRWNuclearTechnologies

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• • • 32-1235128-01 determined toreachanacceptable finalflawsize(af)attheendofthedesignlifeoftheplant.Themaximumappliedstressintensity factoratthefinalflawsizeis78.0ksiVin.ThisresultsinasafetyfactorgreaterthantherequiredsafetyfactorofV10(3.16)perIWB-3612(a) ofASMECodeSectionXI.Fortheemergency andfaultedcondition, themaximumappliedstressintensity factoratthefinalflawsizeis76.8ksiVin.Theresulting safetyfactorisgreaterthantherequiredsafetyfactorofV2(1.414)perIWB-3612(b) ofASMECodeSectionXI.Therefore, itisconcluded thatthepostulated flawsizeintheinstrument/temperature nozzleoftheSt.Luciepressurizer isacceptable forthedesignlifeoftheplant(thirtyfutureyears)perIWB-3612oftheASMECodeSectionXI.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page5of30 BAWNuclearTechnologies

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1.0INTRODUCTION

Thepurposeofthisanalysisistoprovideaboundingflawevaluation forallseveninstrument/temperature 1"nozzlesinthepressurizer.

Theevaluation willconsideraconservative flawsizeandwilldetermine theacceptability ofthepostulated boundingflawforthirtyfutureyearsofplantlife.Thisflawevaluation willbeperformed inaccordance withIWB-3612ofSectionXI,ASMEBoilerandPressureVesselCode.1.1Assumptions a.Theflawtype,orientation andaspecificflawsizethatisconsidered conservative ispostulated inthisanalysis.

b.(Approachtakenforpostulation offlaw-BWNTProprietary

)c.Threehundredandseventyfivefuturecyclesofheatup/cooldown areconservatively assumedfortheremaining designlifeoftheplant.d.Eightfuturecyclesofpressuretestsat10%oftheoperating pressure(2475psia)areassumedoverthenext30years.e.AspecificuppershelfvalueforK,~isusedforthenozzlepenetration region.Thistoughness valueisassumedfortheSA533GradeBClass1basematerialaboveacertaintemperature rangewhenthematerialisveryductlie.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page6of30 B&WNuclearTechnologies

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• • • 32-1235128-01 2.0DESIGNINPUTSa)GeometryofPressurizer NozzlePenetrations Thepenetration configuration ofthepressurizer upperheadsteamspaceinstrument nozzles(four)withthemodifiednozzledesigniscontained inDrawing2998-19321 ofReference 1.Thepenetration configuration ofthepressurizer bottomhead(two)instrument nozzlesandsidetemperature nozzleiscontained inDrawing2998-18709 ofReference 2.minimumpressurizer headthickness

=3.875inminimumpressurizer shellthickness

=4.875inb)DesignTransients/Number ofCyclesThefollowing information wastakenfromReference 3,withthetransient specificinformation fromReference 4(forthefortyyeardesignlifeoftheplant).i)500cyclesofnormalheatup/cooldown forthedesignlifeofthecomponent.

Thenormaloperating pressureperTable5.4-6ofReference 3is2250psia.Atotalof480cyclesofupsetcondition transients.

Themaximumpressurerangeduringupsetcondition transient is660psiandoccursbetween2400psia(abnormal lossofturbinegenerator load)and1740psia(reactortriptransient) withassociated temperature difference of50'Fduringlossofloadtransient iv)(Reference 4).200cyclesofleaktestat2250psia(Reference 4)Theremainder ofthenormaloperating transients i.e.15,000cyclesofpowerchangecyclesfrom15%to100%power,2,000cyclesofsteppowerchangesof10%ofthefullloadand1x10'yclesofnormalvariations of100psiandtemperature differences oflessthan20'F(Reference 4).v)5cyclesofemergency condition transient (complete lossofsecondary pressuretransient),

giveninReference 4.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page7of30 B&WNuclearTechnologies

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• • • 32-1235128-01 Sincetheanalysiswasperformed for30futureyears,only75%oftheabovenumberofcyclesforagiventransient wereconsidered intheevaluation.

c)Materials Thepressurizer headandshellmaterialismadeofSA-533GradeBClass1perReference 1andAddendum2ofReference 4.PerTable5.2-9ofReference 5,theRTNDrofthepressurizer shellmaterialis10'F.d)Applicable ASMESectionXICodePerReference 6,theapplicable ASMESectionXIcodeis1989Edition.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page8of30 B&WNuclearTechnologies

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• • • 32-1235128-01 3.0GEOMETRY, FLAWSIZEANDORIENTATION 3.1GeometryofBoundingPressurizer NozzlePenetration Thereareatotalofseven1"instrument/temperature nozzlesinthepressurizer ofSt.LucieUnit2asdepictedbythedrawingofReference 2.Fouroftheinstrument nozzleare'ontained inthepressurizer upperheadsteamspaceregion.Thesenozzlesarehorizontally orientedinthelowerspherical partoftheupperheadasillustrated inFigure1.Theremaining threenozzlesarelocatedinthelowerregionofthepressurizer asillustrated inFigure2.Twooftheinstrument nozzles(vertically oriented) arelocatedinthelowerheadofthepressurizer.

Theseventhnozzleisa1"temperature nozzlewhichislocatedinthelowercylindrical portionofthepressurizer.

Thecylindrical portionofthepressurizer hasaminimumwallthickness of4.875incheswhereastheminimumwallthickness oftheupperandthelowerheadsis3.S75inches.ThestressanalysisofReference 7tookeachofthesevennozzlepenetration regionsintoconsideration andconstructed anozzlepenetration finiteelementmodeltoboundallinstrument/temperature sensingnozzlelocations.

Foradditional detailsrefertoSection3.3ofReference 7.3.2FlawSizeandOrientation Itispostulated thatthereexistsaspecifictypefiaw(asdepictedinFigure3)withaconservative initialflawdepth.Theorientation ofthisflawwasassumedtobeinax,yplane(seeFigure3).Thisistheworsecaseflaworientation sincethemaximumstressisprimarily duetopressureinducedstressascanbeseenfromtheresultsofthestressesalongtheflawplaneinSection6.0ofReference 7.Theanalysiswillevaluatemaximumstressintensity factorandperformfatigueflawgrowthanalysis.

Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page9of30 B&WNuclearTechnologies

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• "*32-1235128-01 Figure1:UpperPressurizer Region4gP>>~6CAIrn~m~Plgr4o~g4pggF445CThB.E.65Preparedby:A.D.Nana'eviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page10of30 IIII~I~~II/~~II~f1I,Ie'e~'I~~.~~~~

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• • • 32-1235128-01 Figure3:Postulated Flaw"Intensionally LeftBlank--containsBWNTProprietary Information" Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page12of30 B&WNuclearTechnologies

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4.0 MATERIAITOUGHNESS

Thepressurizer shellandheadisSA-533,gradeB,class1perReference 1andAddendum2ofReference 4.TheRT~rofthismaterialis10'F.According toIWB-3612, thearresttoughness curve,KI,inAppendixA,SectionXIofASMEBoiler&PressureVesselCode(Reference 6)wasusedforthisevaluation.

SincetheRTM,rofthepressurizer is10'F,thematerialisconsidered tobeattheuppershelfregionfortemperatures above192'F.Becausethemaximumstressisprimarily duetopressure, thecorresponding temperatures duringthetransient whenthemaximumstressesoccurinthepressurizer shell/head areabove500'F.Sincetheevaluation isbasedonaflawinthenozzlepenetration regionofthebasemetalwithirradiation embrittlement, aspecificuppershelfvaluewasused.Itisnotedthatanyshiftduetoirradiation isnegligible, i.e.nochangesinRT>>~valueofthepressurizer withincreases inEffective FullPowerYears(EFPYs').

Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page13of30 B&WNuclearTechnologies

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• • • 32-1235128-01 5.0LOADINGCONDITIONS/STRESSES 5.1NormalandUpsetLoadingConditions Thestressesduetonormalandupsetconditions arecontained inSection6.0ofReference 7.Thecomposite transient evaluated intheanalysisconsisted of100'F/hrheatup,100%powersteadystatecondition, aboundingupsetcondition transient anda200'F/hrcooldownrateasdescribed inSection5.0ofReference 7.Thenormalandupsetcondition transient casesaresummarized inTable1.TheresultsoftheanalysisinReference 7showedthatthemaximumstressesoccurduringanupsetcondition whenthepressure.

Thenextlargeststressstateoccursduringsteadystateconditions whenthepressureis2250psia.Thesemaximumstressstatesareprimarily duetopressureinducedhoopstressandoccursattemperatures wellabove500'Fwhenthematerialisatupper-shelf.

Transient case2awasconservatively evaluated for375cycles,inSection6.1,toboundthe360cyclesassociated withalltheupsetcondition transients aswellasthe375cyclesofplantstartupandshutdownand150cyclesofleaktests.Inaddition, 8cyclesofpressuretestswereevaluated.

Duringnormalcooldownthemaximumstressoccursat560'Fwhenthematerialisatupper-shelf.Toensurethatthefracturetoughness margin(factorofsafetyof>10perIWB-3612) ismaintained, throughout theentirecooldowntransient, thetimeattheendof200'F/hrcooldownisalsoevaluated.

Atthistime,thebulkfluidtemperature isat70'Fandmaximumthermalstressesaredeveloped inthepressurizer shell/head.

Adequatefracturetoughness marginduringtheentireheatup/cooldown wasdemonstrated inSection6.1.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page14of30 BOWNuclearTechnologies

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• • • 32-1235128-01 Table1:NormalandUpsetCondition Transient CasesTransient

Category, CaseNormal,laNormal,lbNormal,lcNormal,ldDescription ofTransient TimeEndof100'F/hrheatup(max.stressduringheatup)100%powersteadystateCooldownat560'F(max.stressduringcooldown)

Cooldownat70'F(max.thermalstressduringcooldown)

Pressure(psia)225022501133Temperature

('F)65365356070NumberofCycles'75 Normal,lePressureandtemperature fluctuations duringoperation d,P5100h,T520765,000Upset,2aUpset,2bUpset,2cTest,3Atmax.pressure(lossofturbinegenerator load)53'Fstepup53'Fstepdown110%ofoperating pressure2400240017402475653600-653653-6006533604Associated with30futureyearsofplantlife.Basedonconsidering 75%ofthedesigncyclesgiveninReferences 3and4.Thiscaseisnotspecifically evaluated inReference 7.Conservatively assumedtobeone-halfthestressesduetothetransient cases2band2c.11,250cyclesofplantloading/unloading, 1,500cyclesof10%steploadincrease/decrease and750,000cyclesofnormalpressurevariation areconservatively groupedbythistransient case.Thereareonly30cyclesoflossofturbinegenerator load,however,300cyclesofreactortriptransient and30cyclesoflossofprimaryflowtransient areconservatively groupedbythistransient case.Preparedby:A.D.NanaReviewedby:K.K.YoonDate;Feb.1995Date:Feb.1995Page15of30 B&WNuclearTechnologies

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• • • 32-1235128-01 Inadditiontothe375cyclesofplantstartup/shutdown and8cyclesofpressureteststhereare11,250cyclesofplantloading/unloading, 1,500cyclesof10%steploadincrease/decrease and750,000cyclesofnormalpressurevariation

(+/-100psi,+/-7'F)asgiveninReferences 3and4.Reviewofthesetransients showthatthesetransients canbegroupedasasingletransient with765,000associated cyclesofmaximumpressurevariation of100psiandtemperature variation oflessthan20'F.Theassociated stressrangeduetothistransient shouldbelessthanone-halfthestressrangefortheupsetcondition stepchangetransient giveninReference 7.Thestepchangecondition transient considered pressurevariation of660psiandtemperature variation of53'F.Therefore, itisconservative touseonehalfthestressrangeofthestepchangeupsetcondition transient.

5.2Emergency andFaultedLoadingConditions Theonlyemergency andfaultedcondition designtransient (pressurizer pressureandtemperature versustime)providedinReferences 3and4isthelossofsecondary pressuretransient (anemergency condition transient).

Thefaultedcondition transients described inReferences 3and4are;i)thoseduetosafeshutdownearthquake withnormaloperation atfullpowerandwithandwithoutpiperupturecondition andii)thoseduetoLOCA.However,perTable3.9-38ofReference 3,therearenoassociated cyclesforthefaultedcondition transients.

Therefore, theonlytransient evaluated (inReference 7)forthisloadingcondition isthelossofsecondary pressuretransient.

Duringthistransient thepressurizer experiences asignificant cooldownrate.Asaresultofthiscooldownrate,hightensilestressesattheinsidesurfaceofthenozzlepenetration regioncanbeproduced.

Thisisreflected inthestressresultsgiveninSection6.0ofReference 7whichproducedthemaximumhoopsurfacestressamongstallthetransients analyzed.

However,thestresses(hoop)alongthefiawplaneatthepostulated flawsizeandbeyondareinfactlowerthanthoseduringsteadystatecondition at2250psia.Also,thematerialremainsatuppershelfsincetheminimumtransient temperature reachedduringthistransient is348'F.Thistransient casewillnonetheless beevaluated inSection6.2.Thereare4cyclesassociated withthistransient case.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page16of30 B&WNuclearTechnologies

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6.0 FLAWEVALUATION

Aspecificflawtypeisassumedforthisanalysis.

Thestressintensity factor,KforthisflawgeometryisgiveninReference 8.Theflawsolutiongiveninthisreference isutilizedtoevaluatethepostulated flawintheoneinchpressurizer instrument/temperature nozzlesofSt.Lucieunit2.Thesolutiongivenaboveisapplicable fortheflawplaneillustrated inFigure3,Hence,thestressesareobtainedalongthisflawplaneasillustrated inFigure6.2ofReference 7.Toaddressthestressintensity factorsalongtheentirecrackfront,theinformation contained inReference 9isutilized.

Reference 9hasevaluated thestressintensity factorsduetopressureinducedhoopstressesinanozzlecornerwithaquartercircularcrackgeometry.

Threeflawsizeswithflawsizetothickness ratiosof0.15,0.26and0.34wereinvestigated inthisstudy.Thisstudyprovidedthenon-dimensional stressintensity factorsasafunctionofthecrackfrontangle,8foreachofthethreeflawsizesasillustrated inFigure11ofReference 9.Fromthisfigureitisclearthatthestressintensity factornearthesurfacesofboththevesselandthenozzleboresideisslightlygreaterthanthestressintensity factoralongtheflawplaneconsidered inthisanalysis.

Forthetwolargerflawsizes(flawsizetothickness ratiocomparable tothisevaluation),

thestressintensity factornearthesurfacesisabout5to10percenthigherthanalongthepostulated flawplane.Therefore, todetermine maximumflawgrowthwithconsideration ofallcrackfrontangles,thestressintensity factorsobtainedusingtheaboveequations willbeincreased by10percent.Thisisaconservative practice.

Thepostulated flawintheinstrument nozzleisevaluated fornormal/upset condition andemergency/faulted condition asgivenbelow.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page17of30 BAWNuclearTechnologies

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• • • 32-1235128-01 6.1FlawEvaluation forNormalandUpsetLoadingCondition LoadsAsdiscussed inSection5.1,thefollowing boundingtransient casewasanalyzedforthenormalandupsetcondition loading.Transient case2awasevaluated for375cycles.Themaximumtensilestressstatealongtheflawplaneoccursduringthiscondition whenthepressurizer isassumedtocyclefromaninitialstress-free statetoamaximumpressureof2400psiat653'F.Thisstressstatewillbeconservatively assumedtooccurforall375cyclesofnormalheatup/cooldown.

Thisisnotanoverlyconservative assumption considering thefactthatthehoopstressesarelargelypressureinducedandtheupsetpressureisonlyslightlygreaterthanthesteadystatepressure.

Asafirststep,athirdorderpolynomial equationtothestressesfromthefiniteelementanalysisresultswasmade.Theresulting stressesusingthepolynomial equationagreeverywellwiththefiniteelementmodel(FEM)stressesasillustrated inFigure4.Thenumerical valuesforthesestressesarealsogiveninTable2.TheFEMstressesareforthemaximumupsetcondition pressurestressat2400psiaasgiveninTable6.4ofReference 7.Thestressintensity factor,Kfortheinitialflawsizeisdetermined first.Nextafatigueflawgrowthanalysiswasperformed for375cyclesusingtheabovemaximumupsetcondition stressesasgiveninTable3a.Thefatiguecrackgrowthrateis:da/dN=C,(hK,)"whereda/dNisthecrackgrowthrateinmicro-inch percycle,d,K,isthemaximumK,minusminimumK,(inthiscasetheminimumK,iszero),C,andnarematerialconstants andareobtainedfromthefatiguecrackgrowthratecurvewhichisgiveninFigureA-4300-1ofReference 6.Fromthisfigure,itcanbeseenthatforasurfaceflaw(waterreactorenvironment) withanRratio50.25andd,K,219ksiVin,theapplicable materialconstants areC,=1.01x10'in/cycle andn=1.95.Theflawsizeattheendof375cycles,wasdetermined andthemaximumappliedK,wascalculated tobe75.30ksb/in.Also,8cyclesofpressuretestsat2475psigwereconsidered intheanalysis.

Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page18of30 0B&WNuclearTechnologies

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• • • 32-1235128-01 Figure4:FEMthroughwall stressesversuspolynomial fitstresses"Intensionally LeftBlank--containsBWNTProprietary Information" Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995D*:~F*b.195Page19of30 BAWNuclearTechnologies

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• • • 32-1235128-01 Table2:Spreadsheet forthirdorderpolynomial equationandcomparison toFEMstresses"Intensionally LeftBlank--containsBWNTProprietary Information" Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page20of30 B&WNuclearTechnologies

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• • • 32-123512S-01 Table2(cont'd)"Intensionally LeftBlank--containsBWNTProprietary Information" Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page21of30 BAWNuclearTechnologies

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• • • 32-1235128-01 Attheendof8cyclesofpressuretests,themaximumappliedK,=77.75ksiVin.Inaddition, thereare765,000cyclesofpressureandtemperature variations.

TheRratio(K,;JK,~forthiscaseis0.95andsinceb,K,islessthan3.3ksiVin,theapplicable materialconstants areC,=1.2x10"in/cycle andn=5.95.Thefatigueflawgrowthdueto765,000cyclesoftheabovetransient iscomputedusingtheflawsizeaAer375cyclesofheatup/cooldown and8cyclesofpressuretestsastheinitialflawsize.TheresultsgiveninTable3balsoshowstheconsideration of765,000cyclesdiscussed above.Themaximumappliedstressintensity factoratthefinalflawsizeis:K,(af)=78.0ksiVin.ThisresultsinasafetyfactorgreaterthantherequiredsafetyfactorofV10(3.16)perIWB-3612(a)ofReference 6.Also,asdiscussed inSection5.1,toensurethatthefracturetoughness marginismaintained, throughtheentirecooldowntransient, thetimeattheendofthe200'F/hrcooldownisevaluated.

ThemaximumappliedK,attheendofcooldownwasdetermined tobe9.0ksiVin.Theassociated fracturetoughness, K,iwasobtainedfromtheequationgivenonPageC-18ofReference 8.Usingthisequation, thefracturetoughness at60'Fis56.5ksiVin.Therefore, thereisasafetyfactorof6.28forthiscondition whichissignificantly greaterthantherequiredsafetyfactorofV'10perIWB-3612(a) ofReference 6.6.2FlawEvaluation forEmergency andFaultedCondition LoadsAsdiscussed inSection5.2,theonlyemergency andfaultedcondition transient requiring evaluation isthelossofsecondary pressuretransient whichhas4cyclesassociated withit.TheresultsoftheanalysisareprovidedinTable5.Sincethistransient occursfollowing asteadystatecondition, hK,associated withthistransient isonly5.68ksiVin.Also,theflawgrowthassociated withthistransient isinsignificant.

Themaximumappliedstressintensity factoratthefinalflawsize(af)fortheemergency andfaultedcondition is:K,(a,)=76.79ksiVin.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page22of30 B8rWNuclearTechnologies

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• • • 32-1235128-01 Aspreviously notedinSection5.2,thematerialremainsatuppershelfduringthistransient Therefore, thisresultsinasafetyfactorfortheemergency andfaultedcondition whichissignificantly greaterthantherequiredsafetyfactorofV2perIWB-3612(b)ofReference 6.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page23of30 B&WNuclearTechnologies

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• • • 32-123512S-01 Table3a:FatigueFlawGrowthAnalysisfor375cyclesofnormalheatup/cooldown "Intensionally LeftBlank--containsBWNTProprietary Information" Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page24of30 BAWNuclearTechnologies

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• • • 32-1235128-01 Table3b:FatigueFlawGrowthAnalysis(cont'd)forremaining normaloperating transients "Intensionally LeftBlank--containsBWNTProprietary Information" Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995D.'Pb.5Page25of30 B&WNuclearTechnologies

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• • • 32-1235128-01 Table4:Summaryofflawsizesancheckwithacceptance criteriafornormalandupsetcondition "Intensionally LeftBlank--containsBWNTProprietary Information" Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995D*:~I'*t.Page26of30 B&WNuclearTechnologies

• • • BWNTNON-PROPRIETARY

• • • 32-1235128-01 Table5:Summaryofflawgrowthanalysisandcheckwithacceptance criteriaforemergency andfaultedcondition "Intensionally LeftBlank--containsBWNTProprietary Information" Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995D*:~b.95Page27of30 BOWNuclearTechnologies

• • • BWNTNON-PROPRIETARY

• • • 32-1235128-01

7.0CONCLUSION

S Considering alltheapplicable designtransients, theinitialpostulated flawsizeof0.875inchesintheinstrument/temperature nozzleoftheSt.Luciepressurizer wasdetermined toreachafinalflawsize(af)of1.055inchesafter30futureyearsplantlife.Forthenormalandupsetcondition themaximumappliedstressintensity factoratthefinalflawsizeis78.00ksiVin.Theresulting safetyfactorisgreaterthantherequiredsafetyfactorofV10(3.16)perIWB-3612(a) ofReference 6.Theanalysisconsidered allcrackfrontanglestodetermine themaximumappliedstressintesityfactorandensureboundingfatigueflawgrowth.Fortheemergency andfaultedcondition, themaximumappliedstressintensity factoratthefinalflawsizeis76.79ksiVin.Theresulting safetyfactorisgreaterthantherequiredsafetyfactorofV2perIWB-3612(b) ofReference 6.Therefore, itisconcluded thatthepostulated flawsizeintheinstrument/temperature nozzleoftheSt.Luciepressurizer isacceptable forthethirtyfutureyearssofplantlifeperIWB-3612oftheASMECodeSectionXI.Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page28of30 BOWNuclearTechnologies

• • • BWNTNON-PROPRIETARY

• • • 32-1235128-01

8.0REFERENCES

1.'lorida Power&LightDrawingNo.2998-19321, Rev.0,"TopHeadInstrument NozzlesRepair".2.'lorida Power&LightDrawingNo.2998-18709, Rev.1,"Pressurizer GeneralArrangement".

3.BWNTDocument38-1210589-00, "Pressurizer Instrument Nozzles,FMDesignInput,"forSt.LucieUnit2,dated11/11/94(FP&LNumberJPN-PSLP-94-603, File:PSL-100-14).4.BWNTDocument38-1210588-00, "Pressurizer Instrument Nozzles,FMDesignInput,"forSt.LucieUnit2,dated11/11/94(FP&LNumberJPN-PSLP-94-631, File:PSL-100-14).5.'t.LucieUnit2UpdatedFinalSafetyAnalysisReport,throughAmendment No.9,datedOctober1994.6.ASMEBoilerandPressureVesselCode,SectionXI,1989Edition.7.BWNTDocument32-1235127-00, "Stresses forSt.LucieUnit2,Pressurizer LEFM,"byA.M.Miller,datedNovember1994(BWNTPROPRIETARY DOCUMENT).

8.SourceReference forFManalysisapproachusedinanalysis.

FManalysisapproachconsidered "BWNT-PROPRIETARY".

9.SourceReference forFManalysisapproachusedinanalysis.

FManalysisapproachconsidered "BWNT-PROPRIETARY".

Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page29of30 B&WNuclearTechnologies

• • • BWNTNON-PROPRIETARY

• • • 32-123512S-01 References markedwithan"asterisk" areretrievable fromtheUtilities RecordSystem.AuthoridProjectManager's Signature Preparedby:A.D.NanaReviewedby:K.K.YoonDate:Feb.1995Date:Feb.1995Page30of30