ML18038A714

Final Rept Entitled, Elastic-Plastic Fracture Mechanics Assessment of Nine Mile Point Unit 1 Beltline Plates for Service Level a & B Loadings.

ML18038A714
Person / Time
Site:	Nine Mile Point
Issue date:	10/16/1992
From:	NIAGARA MOHAWK POWER CORP.
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ML17056C080	List: ML17056C079 ML18038A714
References
MPM-USE-109213, NUDOCS 9210220185
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'>>>>>>>e>>*>>x<<<<>>><<>><<<<>>>>>>>v>>>>>>><<P<<fv October16,19929210220i85 92ioi6PDRADOCK.0500022 itPPDR II4J TableofContents1.0NMP-1LowUseIssue1.1WeldMetalScreening Criterion Calculations

.1.2BaseMetalScreening Criterion Calculations...

1.3Summary...44672.0ApproachtoResolution

~~~~~~~~~~~~123.0Analytical ModelforServiceLevelAandBAnalysis134.014141415151617184.34.41919~~~~~~~~~~~~~~~~~~2020MaterialModels4.1Technical BasisforUseofA302BJ-RCurveModel.............

4.1.1MaterialComposition Analysis4.1.2A302BDuctileFractureBehavior..~.4.2A302BJ-RCurveModel.~.421J~cUSECorrelation 4.2.2J-RCurveDetermination

...A533BJ-RCurveModel...~.........

MaterialParameters forElastic-Plastic FractureMechanics Analysis4.4.1Young'sModulus...4.4.2Poisson's Ratio.....

4.4.3YieldStress5.05.3Elastic-Plastic FractureMechanics Assessment

..5.1ModelDescription

..5.2Calculations forA302BMaterialModel5.2.1PlateG-8-1Analysis5.2.2PlateG-307-4Analysis........Calculations forA533BMaterialModel5.3.1PlateG-8-1Analysis........5.3.2PlateG-307-4Analysis5.4SummaryofConditions Analyzed..4444444444454545456.0SummaryandConclusions

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

717.0References 74 l)N~l 1.0NMP-1LowUseIssueTestingandevaluation mustbeconducted toensurethatnuclearreactorpressurevesselsaresafeintermsofbothbrittleandductilefractureundernormaloperation andduringdesignbasistransients.

Withregardtoductilefractureprotection, AppendixGto10CFR50prescribes ascreening criterion of50ft-lbs.Ifanybeltlinematerials areexpectedtoexhibitCharpyUpperShelfEnergy(USE)(T-Lorientation) below50ft-lbs,thenadditional analysesmustbeperformed toensurecontinued safeoperation.

TheDraftASMEAppendixX[ASME92]wasdeveloped toassistlicensees inperforming elastic-plastic fracturemechanics evaluations forbeltlinematerials withlowuppershelfenergies.

Thisreportdocuments application ofthedraftAppendixXcalculative procedures totwoNineMilePointUnit1(NMP-1)beltlineplates.TheNMP-1beltlinematerials wereevaluated todetermine whetheranymaterials wouldexceedthe50ft-lbscreening criterion.

Theresultsoftheseevaluations areshowninTables1-1and1-2,andwerepresented intheresponsetoNRCGenericLetter92-01[MA92].Withtheexception ofplateG-8-3,onlyL-TCharpydataareavailable forthebeltlineplates.Therefore, itisnecessary toapplyanL-TtoT-Lconversion factortoobtainT-Lorientation properties fortheplates.Sincetheweldmetalisessentially isotropic, orientation considerations arenotimportant forthebeltlinewelds.ThedatainTable1-1weredeveloped usingtheRegulatory Guide1.99(Revision 2)[RG1.99](RG1.99(2))

genericmodel.ThedatainTable1-2weredeveloped usingtheRG1.99(2) procedure withplant-specific data.AsshowninTable1-2,theplant-specific modelshowsthatnoneofthebeltlinematerials areexpectedtofallbelow50ft-lbspriortoend-of-license (EOL).ItisNiagaraMohawkPowerCorporation's (NMPC's)positionthattheplant-specific modelisappropriate.

However,sincetwoofthebeltlineplatesareexpectedtoapproachthescreening criterion, NMPChascommitted toperformanelastic-plastic fracturemechanics assessment.

Furtherdetailsconcerning thescreening criterion calculations areprovidedinSubsections 1.1and1.2below.1.1WeldMetalScreening Criterion Calculations FullCharpycurvesfortheNMP-1beltlineweldswerenotmeasuredatthetimewhenthevesselwasfabricated.

However,Charpydataat10'FweremeasuredbyCombustion Engineering andthesedataaresummarized inReferences

[MA90]and[MA91].Aninnovative methodology

[MA85]wasdeveloped todetermine theinitialRT~~forcaseswherethedatarequiredbytheASMECodearenotavailable.

ThisapproachwasappliedtotheNMP-1beltlinematerials andtheresultsaredescribed inReference

[MA90].Themethodology forRT~rdetermination includesestimation oftheunirradiated USEincaseswherefullCharpycurvesarenotavailable.

WeldW5214/5G13F isthesurveillance capsuleweld.Thisweldwasnotmadeusingthesamewireheatorfluxlotasthebeltlinewelds.However,theweldmaterials weremanufactured bythesamesuppliers, theweldwiretypeandfluxtypearethesame l4tI&h4jc (RACO03wire,ArcosB5flux),thesameprocedure wasused,andtheCuandNicontentisrepresentative ofthebeltlineweld1248/4M2F

[CE90,MA91].Ithasbeenassumedthatthecapsuleweldmaterialissimilartothebeltlineweldsintermsofitsmechanical behaviorresponse.

Theirradiated CharpydataforthecapsuleweldmaterialwasanalyzedusingtheSAMMcFRACcode[McFRAC].

Thiscodeisbasedonanon-linear, leastsquares,regression analysisusingtheWeibullstatistic.

TheWeibullstatistic hasbeenshowntobethecorrectstatistic foranalysisoffracturedatabyconsidering themicrostructural mechanisms involvedinthefractureofferritic, pressurevesselsteels[MA85a].Theconfidence bandsaremeasuresof'thegoodnessoffit'nddonotindicatetheengineering 95%statistical errorspread.Thisuncertainty mustbeanalyzedusingconventional statistical methods.However,theMcFRACconfidence intervals areusedtomeasureconfidence inthefitofaparticular datasetaswellastheinherentscatterduetothefractureprocess.Theseerrorbandsmustbecalculated, particularly forsparsedatasets,becauseinmanycasestheabilitytofitsparsedatadrivestheuncertainty.

TheMcFRACanalysisfortheirradiated capsuleweldisshowninFigure1-1.Theprocedure usedtocalculate theRT~oftheNMP-1beltlineweldsrequiresestimation oftheunirradiated USE.Odette'syieldstrengthmodel[OD86]wasusedtoestimatethesurveillance weldunirradiated USEusingtheirradiated USEasinput.Inparticular, USE'USEwhere,f=fractional changeinUSEf=9.0x10do+0.02(ha-40)',a=changeinyieldstrengthduetoirradiation USE'unirradiated USEUSE=irradiated USETheirradiated USEwasmeasuredat7.98EFPYandfoundtobe110ft-lbs.UsingOdette'smodelandthemeasuredyieldstrengthchange,theunirradiated USEforthesurveillance weldisestimated tobe128ft-lbs.Anotherimportant aspectoftheRT~revaluation, whichwasusedinthebeltlineweldUSEevaluation, istheestimation ofthe95%confidence intervalforenergymeasurement (2@a)atthe50ft-lblevel.The2'orthesurveillance weldatthe50ft-lblevelwasestimated at13.5ft-lbs.Thisestimateisconsistent withtheuncertainty indetermination

~~~<;sM~1I4A1IJ oftheUSEfortestsconducted ontheuppershelf.Theminimumunirradiated USEdataforthebeltlineweldsshowninTable1-1wasdetermined assumingthattheCharpybehaviorofthesurveillance weldissimilartotheresponseforthebeltlinewelds.Toensureconservatism, themeasuredirradiated USEwasusedasanestimateoftheunirradiated USE.Themeasuredirradiated USEforthesurveillance weld(110ft-lbs)wasthenreducedby2cra(13.5ft-lbs)plusanadditional 6.5ft-lbforconservatism.

Thislowerboundestimateof90ft-lbswasconservatively assumedtorepresent theunirradiated USEofthebeltlinewelds.InresponsetotheNRC'srequest,additional analysesarebeingperformed tomoreaccurately characterize theuncertainty intheRTNDTandUSEestimation procedure, andtheresultsoftheseanalyseswillbereportedtotheNRCinthenearfutureunderseparatecover.1.2BaseMetalScreening Criterion Calculations Inordertoidentifythebeltlineplateswhichmaypotentially fallbelowthe50ft-lb~screening criterion, theguidanceinparagraph C.1.2ofRG1.99(2) wasfollowed.

SinceonlyL-Torientation dataareavailable formostofthebeltlinematerials, theReference

[MTEB81]guidancewasusedtoconvertfromtheL-TtoT-Lorientation.

Inparticular, theL-Tvaluesweremultiplied by0.65toobtaintheT-Lorientation estimates.

AsshowninTable1-1,basedontheseconservative models,platesG-307-4andG-8-1wereidentified asthebeltlinematerials whichmayexceedthescreening criterion.

PlateG-307-4isalsothecriticalplatematerialfromanARTNDTperspective.

BasedontheresultsoftheRG1.99(2) genericmodelanalysis, furthercalculations wereperformed forplatesG-8-1andG-307-4onaplant-specific basis,Examination oftheirradiated uppershelfdatapresented inReference

[MA91]suggeststhattheshelfdropisnegligible.

However,thisconclusion istentative forplateG-8-3sincetherearenotsufficient USEdataavailable forstatistical analysis.

CapsuleBisscheduled forwithdrawal duringthe1996outage.Thiscapsulecanprovidethedataneededforverification ofasmalluppershelfenergydecreaseforboththeG-8-1andG-8-3materials, InthecaseofplateG-8-1,therearethreeirradiated andthreeunirradiated USEpointsavailable foranalysis.

Thesedataaresummarized inTable1-3.Comparison ofthelinearaveragessuggeststhattheAUSEissosmallthatitiswithinthemeasurement uncertainty.

Ifthe8USEisconservatively calculated usingthemeanoftheunirradiated dataandthelowestirradiated datapoint,thebUSEis10%.Similarly, ifthebUSEiscalculated usingthelowestirradiated andunirradiated points,theb,USEis5%.TheG-8-1Cucontent(0.23Wt.%)isclosetotheG-307-4Cucontent(0.27Wt.%),Therefore, achemistry correction wasnotapplied.TheReference

[MTEB81]L-TtoT-Lconversion factorof0.65appearstobeoverlyconservative fortheNMP-1beltlineplates.Inparticular, themeasuredL-TtoT-Lconversion is0.82[MA91].Applyingthesematerial-specific factors,thebestestimateUSEdataforplatesG-8-1andG-307-4aregiveninTable1-2.

~i~ly1Iy~C.

ThehUSEestimates inTable1-2wereobtainedusingtheguidanceofparagraph 2.2ofRegulatory Guide1.99(Rev.2)withanITtoT-Lconversion factorof.8andanassumedDUSEof10%at7.98EFPY.TheL-TtoT-Lconversion factorof0.8wasobtainedusingtheplateG-8-3lowestmeasuredUSEdatameasuredinboththeL-TandT-Lorientations.

Basedonthisanalysis, itispredicted thatthecriticalplateUSEwillnotfallbelow50ft-lbpriortoEOL.Itisrecognized thatadditional dataandanalyseswillbeneededtoconfirmtheplant-specific calculations.

Theon-goingNMPCworktodevelopmaterial-specific modelsisdescribed inSection2.0.1.3SummaryInsummary,NMPCbelievesthatthemodelsusedtocalculate theTable1-1dataareoverlyconservative fortheNMP-1beltlinematerials andtheplant-specific analysisisrepresentative oftheactualplatematerialcondition.

Microstructural dataobtainedtodateindicates alargepopulation ofMnSinclusions, MO,Cprecipitates, andFe,Cprecipitates intheunirradiated plate[FR92].Theseprecipitates andinclusions havebeenshowntobestableunderirradiation.

Ithasbeenproposed[MA91b]thattheloweringoftheuppershelfduetoneutrondamageinsteelswithinitially highconcentrations ofparticles isexpectedtobenegligible sincetheirradiation induceddefects(Curichprecipitates, microvoids) willnotsignificantly influence thefractureprocessontheuppershelf.Asdiscussed earlier,theReference

[MA91]datasupportthisproposition.

Accordingly, itisinappropriate toapplygenericcorrelations, developed usingdataforlowsulfursteels(A533B),topredicttheAUSEfortheNMP-1platematerials.

Therefore, asdescribed inSection2.0,NMPCisdeveloping material-specific models,whichaccurately modelthephysicsofductilefracture, whichwillyieldaccurateandconservative predictions oftheeffectsofneutrondamageonductilefractureproperties.

Additional workisalsounderwaytoprovidestatistical justification ofthe0.8L-TtoT-Lfactor.Inthemeantime, anelastic-plastic fracturemechanics assessment hasbeenconducted todemonstrate thatthereissufficient margintoensurecontinued safeoperation ofNMP-1.

~J~:l+II Table1-1Estimated UpperShelfEnergyforNMP-1BeltlineMaterials

[MA92]MaterialPlatesWt.%CuMinimumUnirrad.USE(ft-lb)L-T'inimumUnirrad.USE(ft-fb)T-L'rradiation Decrement IUSE(%)12/16/91irradiation Decrement hUSE(%)EOL(25efpy)'redicted USE(T-L)'2/16/91 (ft-Ib)Predicted USE(T-L)'t EOL(25efpy)'ft-Ib)

G-8-3/G-8-4 0.18G-8-10.236-307-30.206-307-40.276-307-100.227882100809764/50753.365.0'2.0'3.1 1517162017172019232054.444.254.641.652.453.142.652.740.050.5WetdsW5214/5G13F 0.1886054B/4E5F 0.221248/4K13F 0.221248/4M2F 0.22100904904904172020202023232383.072.072.072.080.069.369.369.3'heL-TandT-Ldesignations applytoplatematerialonly'easuredusingarchiveplateintheT-Lorientation

'rradiatedvalue measuredatafluenceof4.78x10"n/cm'Conservatively estimated usingdatain[MA90]and[MA91]'astfluenceof7.26x10"n/cm'tthepeak1/4Tposition'astfluenceof1.44x10"n/cm'tthepeak1/4Tposition'atafromReference

[CE90]'urveillance Weld'alculated bymultiplying L-Tdataby0.65 I1'\y1,II Table1-2BestEstimateUpperShelfEnergyforPlatesG-8-1andG-307-4G-8-1G-307-4MinimumUnirrad.USE(ft-lb)L-T8280MinimumUnirrad.USE(ft-lb)T-U65.664.0Irrad.Decre-menthUSE(%)12/16/91~

Irrad.Decre-ment'USE(lo)

EOL(25EFPY)1313Predicted USE(T-L)12/16/91(ft-ib)58.456.9Predicted USE(T-L)atEOL(25EFPY)4 (ft-lb)57.155.7'lateG-8-3measuredL-TtoT-Lconversion of0.8appliedFastfluenceof7.26x10"n/cm'tthepeak1/4Tposition'aragraph 2.2ofRG1.99(Rev.2)used.bUSEconservatively calculated usingaverageunirradiated dataandlowestirradiated datum'astfluenceof1.44x10"n/cm'tthepeak1/4Tposition g1 Table1-3USEDataforPlateG-8-1Unirradiated USE(ft-Ib)Irradiated'SE (ft-Ib)MeasureddataMeasureddataMeasureddata8283957899104AverageofMeasuredData86.793.6ShiftbasedonLowestMeasuredData8278ShiftConservatively BasedonMeanUnirradiated andLowestIrradiated Data86.778'hiftisnegligible andwithinexperimental scatter'rradiated toafastfluenceof4.78x10"n/cm'0 kII 125ClI1-'I00CSV5kkkkkk//kkkkAJkkkkkkkkkkekkk-150150300--TESTTEMPERATURE (F)NINEINILEPOINTUNITI~WELD52'I4/5G43F(SURYEILLANCE WELD)IRRADIATED DATAWEIBULLFITTRANSITION WEIBULLFITUPPERSHELFHYPERBOLIC TANGENTFITCONFIDENCE LIMn(95+)CONFIDENCE LIMn(e5%)CONFIDENCE LIMIT(86%)CONFIDENCE LIMn(esca)UNIRRADIATED DATAUNIRRADIATED CHARPYCURVEFigure1-1CharpyImpactEnergyVersusTestTemperature forIrradiated WeldSpecimens fromtheNineMilePointUnit1300DegreeCapsule11 I

2.0 ApproachtoResolution

NMPCiscurrently performing anASMEdraftAppendixXanalysistoresolvethelowUSEissue.Thisreportdemonstrates thatfortheServiceLevelAandBloadings, theNMP-1USElevelswillnotgobelowtheminimumsafeUSElevelbasedontheAppendixXanalysis.

Thisconclusion isvalidregardless ofwhetherthegenericmodelgable1-1)ortheplant-specific model(Table1-2)isused.Inadditiontotheelastic-plastic fracturemechanics assessment, thefollowing elementsoftheNMPCPressureVesselMaterials Integrity ResearchProgramareexpectedtoprovideusefuldataforconfirming marginsofsafety:L-TtoT-Lconversion modelling UpperShelfEnergy(USE)droptrendcurvemodelling

~Miniature specimentechnology development

~Surveillance capsulereinsertion 12 I1

3.0 Analytical

ModelforServiceLevelAandBAnalysis~~Revision11totheDraftASMEAppendixX[ASME92],

whichiscurrently formulated asaCodeCase,wasappliedtotheNMP-1G-8-1andG-307-4plates.Interioraxialandcircumferential flaws,withdepthsof1/4Tandlengthsequalto6timesthedepth,havebeenpostulated.

Toughness properties, whichcorrespond tothepostulated flaworientation, wereusedintheanalysis:

T-Lorientation properties forcircumferential flaws,andL-Torientation properties foraxialflaws.AppendixXdescribes threepermissible evaluation approaches forapplyingtheflawstability acceptance criteriaaccording totheflawstability rules:J-Rcurve-crackdrivingforcediagramapproach; failureassessment diagramapproach; andtheJ-integral/tearing modulusapproach.

ThelatterapproachwasusedintheNMP-1plateevaluations.

Thefollowing evaluation

criteria, specified inAppendixX,wereapplied;(1)Criterion forflawgrowthof0.1inchJi<Jo.i(2)Criterion forflawstability where,P')1.25P,J,=appliedJ-integral forasafetyfactoronpressureof1.15,anda1.0factoronthermalloadingJoiJ-integral resistance ataductileflawgrowthof0.1inchP'internalpressureatflawinstability P,=accumulation

pressure, butnotexceeding 1.1timesdesignpressureSinceJ-Rcurvedataarenotavailable forA302M,analyseswereperformed usinganA302BandanA533Bmaterialmodel.Thematerialproperties usedintheanalysisareaconservative representation ofthetoughness andtensileproperties ofplatesG-8-1andG-307-4atplantoperating temperature.

Furtherdetailsconcerning thematerialmodelareprovidedinSection4.0.13 IIAuVP"irP, 4.0MaterialModelsTheNMP-1belthneplatesareA302Bmodified(A302M)steel.Atthepresenttime,sufficient J-Rdataarenotavailable toconstruct anA302Mmodel.TheNRChasrequested

[TEL92]thattheAppendixXcalculations beperformed usingbothanA302BandanA533Bmaterialmodel.However,asdiscussed below,itisNMPC'spositionthattheA302Bmodelistheappropriate modelfortheNMP-1beltlineplates.Justification fortheuseoftheA302Bmodelisprovidedbelow.However,boththeA302BandA533Bmaterialmodelswereanalyzedinaccordance withtheNRCrequest.4.1Technical BasisforUseofA302BJ-RCurveModel4.1.1MaterialComposition AnalysisTheASTMnominalplatechemistry requirements arecomparedwiththeNMP-1measuredplatechemistry datainTable4-1.TheASTMA302Bsteelwasthe'.steel..used inconstruction oftheolderplantswhichareoperating today.NickelwasaddedtoA302Btoimproveductility, andthissteelwasdesignated A302M.Eventually, theA533Bstandardemerged.Examination ofTable4-1suggeststhattheNMP-1plateswouldbeaccurately modelledbyA533BJ-Rdata.However,theunirradiated USElevelsfortheNMP-1platesaresignificantly lowerthanthoseofA533Bmaterials.

Further,thesulfur(S)levelsfortheNMP-1platesarehigherthanfortheA533Bmaterials usedinthenuclearindustry(Figure4-1).Asaresult,theconcentration ofmanganese-sulfide inclusions isexpectedtobehigherintheNMP-1platesthanintheA533Bplates.Ithasbeensuggested

[MA91B]thathigherparticledensities wouldbeexpectedtolowertheUSEsincetheywouldactasdelamination sitesduringtheductilefractureprocess.Evidenceforthedetrimental effectofSontheUSElevelisshowninFigure4-2.AsshowninFigure4-2,theUSEresponsefortheNMP-1platesisconsistent withthatoftheA302Bmaterialwhichissubstantially lowerthanthatforA533B.Figures4-3and4-4suggeststhatthebeneficial effectsofNicanbeoffsetbyhighSlevels.AsshowninFigure4-4,A302Mmaterials withlowScontenthaveUSElevelsconsistent withthoseofA533Bplates.However,theA302BplateswithSabovethe0.02wt%levelhavesignificantly reducedUSElevels.Insummary,theNMP-1platesareexpectedtoexhibituppershelffracturebehaviorwhichisrepresentative ofA302Bsteelfromamaterialcomposition perspective.

Thisconclusion isbasedsolelyonCharpyUSEdatadependence onchemicalcomposition.

Asdescribed below,theJ-RdataforA302Bsteelismoreconservative thantheJ-RresponseofA533Bsteels.TheJ-Rdatareportedin[HI89]wereusedtoconstruct theNMP-1materialmodel.Thecomposition oftheNMP-1plates,withtheexception ofNicontent,compareswellwiththematerials usedinthe[HI89]studyasshowninTable4-2.14

'tIht*~1~a' Also,theheattreatments andCharpydatafortheNMP-1platescomparewellwiththe[HI89]heattreatments andCharpydata(Table4-3).Therefore, thefracturebehaviorofthe[HI89]materialisexpectedtoberepresentative oftheNMP-1plates.4.12A302BDuctileFractureBehaviorFigure4-5illustrates theJ-Rcurvespecimensizedependence forreactorpressurevesselmaterials otherthanA302B.Joyce[JOY91]concluded thatdeformation J-Rcurveswhicharedeveloped beyondtheJ-controlled regioncancurveup,curvedown,orstayconsistent withJ-controlled data.Joycedeveloped procedures forextrapolation ofdatabeyondthelowhaJ-controlled region.AsshowninFigure4-6,theextrapolated (smallspecimen) dataagreewellwiththe2TCTdata.IncontrastwiththeJ-Rcurvedatatrendsforotherpressurevesselmaterials, Reference

[HI89]reportedanunprecedented sizeeffectforA302Bsteel.As:showninFigure4-7,thethickerthespecimen, thelowertheJ-Rresponselevelafterinitiation.

Whilesimilardatatrendshavebeenobservedforsomepressurevesselmaterials, decreases intheJ-Rcurvesofthemagnitude reportedbyHiserhavenotbeenreportedearlier.Themicromechanical explanation fortheJ-RcurvebehaviorshowninFigure4-7hasnotbeendefinitively established.

Hiser[HI89]hasreportedbrittle-like splits,orlaminatetearing,forallofthespecimens tested.Thesesplitsareorientedinthedirection ofcrackgrowthwithsmallamountsofmicrovoid coalescence intheregionbetweenthesplits.Thesize,relativenumber,anddistribution ofthesplitsareapproximately constantforvariousspecimensizes.Hiserconcluded thatthesplitsresultedfromseparation oftheinterface betweenthematerialmatrixandtheinclusions (sulfides, aluminides) and/orthesplitting ofthemorebrittlealloyrich..bondedstructure (possibly bainite).

Theonlyapparentdifference inthefractureofsmallandlargespecimens isthetotalnumberofsplitsandnottherelativeproportion.

Acompletemicromechanical explanation isnotyetavailable.

4.2A302BJ-RCurveModelReference

[HI89]showedthatalthoughtheJ-Rcurvesaftercrackextension aresignificantly affectedbyspecimensize,J,cisapproximately invariant forspecimens ranginginthickness from.5Tto6T.AlthoughnotstatedbyHiserandTerrell,itislikelythatthematerialresponseintheJ-controlled regionisindependent ofspecimensize,andthisregionoftheJ-Rcurvedominates Jicestimation.

Table4-4liststheJicdatafortheA302Bmaterial.

Theinvariance ofJ,cwithspecimensizeenablesthedevelopment ofacorrelation betweenJ-Rresponseanduppershelfenergylevel.Thiscorrelation isneededtodetermine the15 fPt'~

minimumUSEforwhichtheplantcanbesafelyoperated.

Theapproachusedistodevelopacorrelation betweenJ,candUSE,andthentodetermine lowerboundJ-RcurvesforeachUSElevelofinterest, whichareindexedtotheJicvalue.Thekeyassumptions madeindeveloping thismodelarelistedbelow:Theheattreatment andcomposition oftheNMP-1platesandthematerials usedinthe[HI89]studyaresimilar.Jiccorrelates withUSElevel.TheUSEisapproximately constantfromthetemperature ofonsetof100%shearto550'F.Jicisapproximately constantbetween392'Fand550'F.The6Tdatareportedin[HI89]isrepresentative ofA302Bfullsizevesselbehavior.

Thejustification foreachoftheseassumptions isdiscussed below.Thespecimensizeindependence ofJ,cisshowninTable4-4andthecomparison oftheheattreatments andchemicalcompositions oftheNMP-1plateswiththe[HI89]studymaterials isshowninTable4-3.421JicUSECorrelation A302BJ-Rcurves,J,cdata,andUSEdataweregatheredfromReferences

[HA90],[HI83],[HA82],and[HI89].Analyseswereperformed toverifythevalidityofacorrelation betweenJ,candUSE.InaCharpytestontheuppershelf,thecrackadvanceisaccomplished byplasticdeformation resulting inmicrovoid coalescence, particledelamination, andinsomematerials, banddelamination.

TheCharpytest,therefore, measuresthetotalamountofenergyrequiredtoadvanceastablecrackinaninitially notchedspecimen.

TheJ-Rtestisafundamentally similarprocessinthattheenergyperunitarearequiredtoadvanceastablecrackismeasured.

Ofcourse,theJ-Rtestdiffersinspecimensize,parameters

measured, localstressfield,andthespecimenisalwaysfatiguepre-cracked.

Nevertheless, thebasicprocesswhichismeasuredineachofthetestsissimilar.Infact,itislogicaltoexpectthattheJparameter, measuredatanylevelofcrackextension (ha),wouldcorrelate withUSE,Hawthorne et.al.[HA82]havedemonstrated thisobservation (Figures4-8through4-10).However,itisnotclearthatanon-linear dependence isphysically correct.ThedatausedtodeveloptheJ<<-USEcorrelation inthepresentstudyareshowninFigure4-11.Thisdatasetincludesbothplateandwelddata,irradiated andunirradiated data,aswellasL-TandT-Lorientations.

Thelineartrendinthe16 Il44AI dataisobviousfromtheplot.NoticealsothattheLINDE-80weld,S/A533Bweld,andA302BplatedominatethelowUSE/J<<region oftheplot.ThefactthatJ<<USEdatafordifferent materials, materialheats,anddifferent crackplaneorientations correlate suggestsafundamental relationship betweentheJparameter (atorbeyondinitiation) andtheCharpyUSEformaterials withsimilarflowproperties (E,a~~).Linearregression wasperformed onthedatashowninFigure4-11.ThelinearmodelyieldedR'aluesof0.93.AsshowninFigure4-12,95%lowerboundconfidence intervals weredetermined.

The95%lowerboundlimitcanbedetermined usingthefollowing equations:

J<<=31(USE)USE<75ftlbs'ic=3634+793295(USE),USE>75ft-lbswhere,J<<=in-lb/in'SE

=ft-lbsThe95%confidence limitlowerbounddataaresummarized inTable4-5.Itisimportant tonotethatthedatausedintheJ,c-USEcorrelation isrepresentative ofreactoroperating temperature performance.

Forthedatausedinthecorrelation, theCharpyUSEwasnotastrongfunctionoftemperature.

AtypicalCharpycurveforoneofthematerials usedinthecorrelation isshowninFigure4-13.However,theJ<<valuesdovarystronglywithtesttemperature on,theuppershelf(Figure4-14).Therefore, alloftheJ,cdatausedinthecorrelation development weremeasuredbetween392'Fand550'F.Thevariation overthistemperature rangeisrelatively small.4.2.2J-RCurveDetermination NowthattheJ,c-USEcorrelation hasbeenestablished, thenextstepistodevelopaprocedure fordetermining theJ-Rcurve,atagivenvalueofJ<<,whichaccountsforthespecimensizeeffectreportedin[HI89].The6TJD-hadatasetreportedinReference

[HI89]wasusedtodefinefullthickness vesselbehavior.

Oncetheinitialplateau(700in-lb/in',

ha=0.1in.)isreached,theJ-Rcurveisassumedtobeflat.Thisapproachisconsistent withcurrentASTMdatavaliditylimits.The6TJD-hadatawerereducedbythedifference betweenthe6TtestJ,cvalue(525in-lbfin)andthe95%confidence limitlowerboundJ<<valuegable4-5).17

TheresultsoftheseanalysesareshowninFigure4-15.TheseJ-RcurvesaccountfortheA302Bspecimensizeeffectandtheinherentdatascatter.Therefore, theyareexpectedtobeconservative lowerboundstotheactualmaterialperformance.

4.3A533BJ-RCurveModelReference

[EA91]reportedtwomodelsforA533Bbasemetals:aCharpymodelandapre-irradiation Charpy(CVNp)model.Bothmodelswerederivedfromamodifiedpowerlawformulation:

J=C1(ha)~exp[C3(ha)]TheJ,datawerefittothefollowing equation:

lnJ,=lnCl+C2ln(d,a)+C3(ha)using,C2=dl+d2lnCl+d3lnBNC3=d4+d5lnCl+d6lnBlnCl=al+a2lnCVN+a3T+a4lnBwhereha=crackextension (in.)J,=deformation J-integral (kip-inIin')

B=specimennetthickness (in.)T=testtemperature

('F)CVN=Charpyimpactenergy(ft-lb)(44)Theconstants aregiveninTable4-6.TheCVNpmodelusedexpressions (4-2),(4-3),and(4-4)withthefollowing formforlnCl:lnCl=al+a2InCVN+a3T+a4B+a5gtwhere,18 II4h'LpOk~I gt=fluencex10is(E)1MeVg'cm~)Easonet.al.concluded thattheCharpyandCVNPmodelsareequallygoodfortheJddata.Therefore, sincethemodelsareequallygood,theCharpymodelwasusedforthecurrentcasesincethefunctional formismoreconvenient fordetermination ofJ-RcurvesasafunctionofUSE.The95%C.I.datawasobtainedbyusingthestandarddeviation ofthedataaboutthemodel(Se),whichisgiveninTable4-6.Therefore, J,-hadataaredetermined fortheCharpymodel,andthenmultiplied by0.789toyieldthe95%lowerboundconfidence interval.

Thus,thefinalformofequation(4-1)is:J=789.0C1(ha)~exp[C3(ha)~]

(in-lb/in' TheCharpymodel(equation 4-6)wasusedtocalculate thepowerlawparameters asafunctionofUSE.Theresultsofthecalculation areshowninTable4-7.The...:following.

datawereusedinthemodel,BN=7.281in.T=525'FC4=-0.409andthereducedequations forthepowerlawmodelare:C1=exp(-3.3802919

+1.13ln(USE))C2=-0.0047931

+0.116lnC1C3=-0.1397654

-0.00920lnClPlotsoftheJ-RcurvesaregiveninFigure4-16.4.4MaterialParameters forElastic-Plastic FractureMechanics AnalysisRevision11totheASMEAppendixXrequiresseveralmaterialparameter inputsinadditiontotheJ-Rcurvemodel.Thedetermination oftheappropriate parameters fortheanalysisisdescribed inthissectionofthereport.4.4.1Young'sModulusTableI-6.0of[ASME80]wasusedtodetermine theelasticmodulusat500'F.Forcarbonsteelswithcarboncontentof0.3orless,wehave:19 LvyTt4'1tv E=26.4x10'si,atT=500'FThemodulusdecreases withincreasing temperature.

Theoveralleffectofthemodulusontheelastic-plastic fracturemechanics analysisistoyieldmoreconservative results(-5%betweenRTand550'F)asthehighertemperature valuesareused.Therefore, tobeconservative, the500'FmoduluswasusedintheAppendixXanalysis.

Sincetheelasticmodulusisessentially insensitive toneutrondamageforfluencesofinterestforLWRoperation, itisnotnecessary toaccountforradiation damage.4.42Poisson's RatioPoisson's ratioistakenas0.33[DI76].Forthematerialandapplication beingconsidered, itisnotnecessary toadjustfortemperature orneutronfluenceeffects.4.4.3YieldStressTableI-2.1ofReference

[ASME80]showsthatfromRTto500'F,thereisan8ksidropinyieldstress(a).Therefore, thefollowing valuesforcrwereusedintheAppendixXanalysis:

NMP-1PlateG-307-4G-8-1ts~atRTksi69.466.6ssat500'~Fksi 6158TheRTyieldstrengthdataislistedinReference

[MA91].Theuseofloweravaluesresultsinmoreconservative AppendixXanalysisresults.Therefore, the500'Fproperties wereusedintheanalysis.

Theyieldstressincreases withneutronfluence.Asaresult,usingtheunirradiated adatayieldsconservative results.20 Il Table4-1PlateChemiseiht%ElementASTMA302B&302MASTMA533BNMP-1Plates'arbon, maxManganese Phosphorous, maxSulfur,maxSiliconMolybdenum Nickel0.251.07-1.62 0.0350.0400.13-0.45 0.41-0.64 0.251.07-1.62 0.0350.0400.13-0.45 0.41-0.64 0.37-0.73 0.18-0.20 1.16-1.45 0.012-0.021 0.026-0.034 0.17-0.26 0.45-0.52 0.48-0.56

'ukensladelanalysisbyatomicabsorption 21 Il Table4-2Comparison oftheNMP-1PlateChemistry withthe[HI89]StudyMaterialChemistry ElementCarbonManganese Phosphorous SulfurSiliconMolybdenum NickelNMP-1Plates0.18-0.201.16-1.450,012-0.0210.026-0.0340.17-0.260.45-0.520.48-0.56HI89Material0.211.460.0100.0210.240.540.2322 lr Table4-3"Comparison ofNMP-1PlateHeatTreatments andCharpyDatawiththe[HI89]StudyMaterialHeatTreatments andCharpyDataItemNMP-1PlatesSecimensHI89MaterialHeatTreatment 1550-1600'F, 4hr;waterquench,4hr1650+25'F, 6hr;waterquench1150+25'F,10.5hr.,aircool1200+25'F,6hr;aircooltestspecimens stressrelievedat1150+25'F,30hrsstressrelievetestspecimens only1150+25'F,40hrs1150+25'F, 24hr,furnacecoolto600'F,aircoolUSE(T-L)68.5(G-8-3)53.6T302623

JIl, Table4-4SummaryofJ,cDataasaFunctionofSpecimenSizeforA302B'aterial

[HI89]Testedat180'FSecimenIDSpecimenThickness JDeformation (Jn)~i-bi'50-113V50-116V50-114V50-117V50-115V50-118V50-119V50-120V50-121AverageV50-109V50-112AverageV50-105V50-108AverageV50-102V50-103AverageV50-1010.5T0.5T0.5T0.5T0.5T0.5T0.5T0.5T0.5T0.5T1T1T1T2T2T2T4T4T4T6T662560662405628525611657622592674634654594651623600588594525'-Lorientation, USE=52ft-lbuppershelfbehavioratT>150'F24 4

Table4-595%Confidence LimitLowerBoundJ,cDataUSEFT-LBS10I~IN-LB30.82061.63092.435107.840123.24550138.6154.055606570169.4184.8200.2215.67580231.0271.39095100310.9350.6390.2429.925 tgC Table4-6Constants forJ,ModelforA533BSteel[EA91)C2C3a4asd,d3Parameter lnCIa,Variable(constant) lnCVNorlnCVNT(constant) lnCICharpyModel-2.441.13-0.002770.08010.07700.116-0.0412CVN,Model-2,531.15-.002700.0760-0.01040.07700.116-0.0367C4A(4dsd5NPointsS.(constant}

lnCI(exponent) ln@~its-0.0812-0.00920-0.0295-0.40922950.144-0.0812-0.00920-0.0263-0.40822950.145Rc"..os-1.645S,-1S,-2S,-3De0.7890.8660.7490.6490.7880,8650.7480.64726 JJ7 Table4-7A533BMaterialModelforNMP-1MaterialCondition 10ft-lbUSE20ft-lbUSE30ft-lbUSE40ft-lbUSE50ft-lbUSE60ft-lbUSE70ft-lbUSE80ft-lbUSE90ft-lbUSE100ft-ibUSEC10.4591535

1.0 048975

1.5889305 2.1993061 2.8300492 3.4775133 4.1392215 4.8133735 5.4985973 6.1938100 C2-0.0950841

-0.0042264

0.0 489220

0.0866314 0.1158810 0.1397797 0.1599858 0.1774891 0.1929281 0.2067387 C3-0.1326044

-0.1398103

-0.1440256

-0.1470163

-0.1493361

-0.1512315

-0.1528341

-0.1542223

-0.1554467

-0.1565421 27

Mnvs.SforLWRVESSELMATERIALS 0.040.03~eNQPieoioo~~~oo~h0.02CLCO0.010.00oo~ol~~oo~ooooooo~~~~~~~0~~~~~~~~o~\~oo~~oh0hh00+00+4hCO+;+t~++0'+t~~op~~~~oo~~~~~h~~+A5338PlateaA508Plate~A3028Plate0A302MRate0.00.51,0Manganese SVt.%)1.5.2.0Figure4-1PlotofSandMnLevelsforLWRPressureVesselMaterials 28 lI fisC~USEvs.SforLWRVESSELMATERIALS 200~~150LLI-Ih~00CUJCO5080~~~~0~~~0~0~0~~0YI~~a+~;+~yS0~~j~~~\~tt\~0~~0~~OOA0:+~5+"ItloOIgo0'.4+~~~0~~0~0~0~0~0~0~1~1~~1~~~~~~~~Ot(~~0~~~~~~~~~~hj)NMp-1~+~+1~~+A5338PlateaA508Plate>A3028Plate0A302MRate0.000.010.02SulphurONt.X)0.030,04Figure4-2PlotofUSEvs.SContentShowingtheDetrimental EffectofSontheUSELevel29 1

USEvs.NiforLWRVESSELMATERiALS 200~~150I-100CUJCO50~~~~~op~b~~~~ooof~~~o~o~ooO~oÃgoogoo.oVg

~~~5~os~~~'os~~~o~o~o~o~O~~oo~~AooA~oo~~~~~.:pMvg.1~o~~~~~o~~o~~~o~~o~~o~o~~oogo~~~~~~o4~~o~~oo~os+o+Qctp+A533BPhteaA508Rate>A302BPlate0A302MPlate0.00.10.20.30.40.50.60.70.8Nickel0Nt,%)Figure4-3PlotofUSEvs.NiContentShowingtheGenerally Beneficial EffectsofNiontheUSELevel30

CoUSEvs.NiforLWRVESSELMATERIALS 200150Ico100CUJCO50R0~e~~~~~~ezS-.010~o~~~~i~ooooooo.022'<<.026',

i~~~~e~~~~~~~~~'~~~~~~o~~~~~~~4e4e'.pS-.010~ooooo,~ooooo>>

~~~oooQ~~~~8.01Bp;pprOi7':..

"~)g+ep".pS.917~gppS<.020~~~~~~I~~~~~oo~ooo~ooe~~~ooooAeoooo'.pS.030e~o~oo~oo~~~~~~~~~o~~~~~e$~eooo~eoeeooo~oo~+A533BPlateaA508Plate<A302BPlate0A302MPlate0,00.10.20.3OA0.50.60.70.8Nickel0/Vt,%)Figure4-4PlotofUSEvs.NiContentShowingtheImpactofSContentinCounteracting theBeneficial NiEffect31 l4 400035003000E2500c7200015001000500~o0~ox+xxxx++44+OOC1O000.394TCTL0.5TCTX05TCT01TCTG2TCT00.10.20.30.40.50.60.7JA.8CRACKEXTENSION (in.)Figure4-5:J-RCurvesforLinde80Welds[JOY91]32 I

4000350030002500CO2000C1500LimitofExtendedValidityRegionfor1TSpecimens lT~0.5T~0.394T1000tLimitofExtendedValidityRegionfor1/2TSpecimens Cl2TCTOATA500LimitofExtendedValidityRegionfor0.394TSpecimen0.10.20.30.40.50.60.7O.BCRACKEXTENSION (in.)Figure4-6:Extrapolations onSmallSpecimenJ-RCurves-Linde80Welds[JOY91].33

~'%g A302BJ-RDATAFORVARIOUSSPECIMENTHICKNESSES 15001000OHcd500O004OeO~~0~gA~o)~~~~~~~~~~J~>44mzqg44~~k~~o~~~4~~~~WO~~~o&IH~~~12Deltaa(In.}~A~~~~~~~~~~(~~I~~~~~~~~~01~~~~~0~0~<I0,5TDATA<0.5TDATA00,5TDATA40.5TDATA*0.5TDATA*0.5TDATA1TDATA+1TDATA02TDATAi2TDATA<4TDATA>4TDATA~6TDATA4Figure4-7Comparison ofJ~-RCurvesforA302BPlate(DataTakenFrom[HI89])34 1

EPRINUCLERRVESSELSTEELS288C,1T-CT,28-25/SGFilledSymbols=Irradiated kkLh188Cv(joule)158Figure4-8Comparison ofJ<<andtheCvUpperShelfLevelforAllSteelsInvestigated

[HA82]35 ml>

EPRINUCLERRVESSELSTEELS688288C,1T-CT,28-25/SGFilledSymbols=Irradiated

<880OOOyQ~8~O!88128Cv(joule)168288Figure4-9Comparison ofCvUpperShelfLevelwiththeJLevelataPointontheRCurveWhereJfl=4.4.Here,theCorrelation withCshelfisBetterthanthatbetweenJ,eandtheCvShelf[HA82]36

EPRINUCLERRVESSELSTEELS880288oC~1T-CT,28-25/SGFilledSymbols=Irradiated 688III-5884/Ah~hLkA~kk188Cv(joule)158288Figure4-10Comparison ofCvUpperShelfLevelwiththeJLevelataPointonthe'RCurvewhereJff=8.8forAllMaterials Investigated Here,theCorrelation withCShelfisBetterthanthatBetweenBothJ,oandJatJff=4.4andtheCShelfIHA82]37

~t(Jic/USECorrelation Data20001500~5It000500vkA303BPLATEA5SSBPLATEA508FORGINGSIA5338WELDLINDE-80WELDLINDE-0091WELD50'100UpperShelfEnergy{Ft-Lbs)Figure4-11DataSetUsedtoDevelopJ,C-USECorrelation 38 II Jic-USE95%C.I.LOWERBOUNDLIMIT200015001000I0500~~:~~y'.~~'.~~.:~I~:0050100USE(Ft-Lbs)150Figure4-12JicUSECorrelation and95%LowerBoundConfidence Limit39

~~

Temperature

('F)288388488688125188CQeR382-H(UBR"l6,CapsuleR,Rs-Irradi ated)CCE-21188J3I7SC5QQ.2S188158PG8258388Temperature

('lkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkk+kkkkkkk+kkkkkkkkk+

Cu~8+Btanhf<T-To)AC)ABCTo~Enlish41~92f't-1b37~21f't-1b85.81OF148~244Ft!ettlc56~84J58.45J47.67OC64.58kCCu~30,f't-1b

<41J)atT~119.7OF48.74CUpperShelf'nergy~79~1f't-1b107.3Jkkkkkkkkkkkkkkkkkkkkkkkkkk kkkkkkkkkkkkkkkkkkk kkkkkkkkkkkkkkkkk kkkkkkkkk+Figure4-13A302BCharpyDataIllustrating theWeakTemperature Dependence oftheUSEonTemperature

[HA90]40

tORNImIit30(NI00CNFt13L3:!30IMa0iruiaiI~(E.I~)+Ci>itIN"0I00IORAFillK li(1l056A!lfC Vf3(NtMQe~IMINgII00IHIQCft%ILIC (e('1-weIOftNILgf fi(30iNiNQo(NII0C~'<H<lttl(C3incI31iJ~(41KFigure4-14PlotofKgcvs.TestTemperature ShowingtheStrongTemperature Dependence ontheUpperShelf[HA90]41

/tf"N A302BJ-RCURVESFORVARIOUSUSELEVELS~95%Cj.LOWERBOUNDJWDATA06TMEANJ-RDATAAT180F-52Ft-Lbs(TL)Q700600600o4QQo300D200~~4g44'~1~~~~~~gott~~;~t44ttpCsRtI..aljA,O,.I,t...AA t,~A1tAMtM~~AA..Jtt~tMMtt~~~~~~~~~~ION509PS44tp'NtIIIIeaftT s0'~~~~~~~I~~~attoo~~~~0Pt~~tt,A}t.A,A,t

~,A,~~A,A~tNbl.tlat@,

A9,0(00.3Deltaa(In.)Figure4-15LowerBound95%CIJ-RCurvesforA302BThickSectionMaterial(6TDataTakenFrom[HI89])42

A533BJ-RCURVESFORVARIOUSUSELEVELS600060004000I3000COEo2000D1000;VSE100FTMrr\rrorr~o~~~~~~~I~~~~~~~~~~~~~~~~~~~~oro$10pgooFTorLBorrrr~ooi:USE-80FTM~~~~~~~~~~~y4~~~~~~~~Ir~~~~~~oo~~~~~o~~~~~~opom~~~~~~~~~QSE~70FT-LBrrr~roI~I~~<~~~~~~~~~>orrr~~~~~~~~~~~oVSF6Qo~~~IIr~VSE60FT-LB)IIIItyo~p~~~~O~~~~~~~~~~~~o~~~~~~oR~:USE-40Fi-LB/Il/Ioor~jr//I:USE30FT-LB//.:USE20FT-LBIUSE10FTM0Deltaa(In.)Figure4-16LowerBound95%CIJ-RCurvesforA533BThickSectionMaterial43 P1L,I 5.0Elastic-Plastic FractureMechanics Assessment

~~~~TheUSEŽcode[USE92],Version2.0,wasusedforcalculation oftheminimumallowable USEsubjecttothedraftAppendixX(Revision 11)evaluation criteria.

TheUSE~Version2.0codehasbeenvalidated inaccordance withtherequirements oftheMPMResearch8'cConsulting NuclearQualityAssurance Program.USEŽallowsJ-Rdatatobeinputaspointwise dataorintheformofpowerlawcoefficients.

Thepointwise datainputoptionwasused.5.1ModelDescription Inadditiontothematerialmodelinput,USEŽ2.0requiresthefollowing inputparameters:

VesselWallThickness VesselInnerRadius7.281in(FSARTableV-1)106.344in(FSARTableV-1)MaximumAccumulation Pressure=1.1DesignPressure=1375psig(Technical Specification Basesfor2.2.1)MaximumCooldownRate100'F/hrAsstatedintheFSAR,the1375psigpressureand100'F/hrcooldownboundalltheServiceLevelAandBloadings.

5.2Calculations forA302BMaterialModel5.2.1PlateG-8-1AnalysisTheresultsofthePlateG-8-1analysis, usingtheA302Bmaterialmodel,areshowninFigures5-1through5-6.Basedonthesecalculations, andtheReference

[ASME92]evaluation

criteria, thelimitingcaseistheaxialflaw(L-Tmaterialproperties).

Application oftheflawinstability criterion, whichisthelimitingcriterion, resultsinanallowable USErangeof23ft-lbsorhigherasshowninFigure5-5.5.2.2PlateG-307-4AnalysisTheresultsoftheplateG-307-4analysisusingtheA302BmaterialmodelareshowninFigures5-7through5-12.AsinthecaseofplateG-8-1,thelimitingcaseistheaxialflaworientation.

Application oftheflawinstability criterion, whichisthelimitingcriterion, resultsinanallowable USErangeof23orhigherasshowninFigure5-11.

4lI~4'-~

5.3Calculations forA533BMaterialModel5.3.1PlateG-8-1AnalysisTheresultsoftheplateG-8-1analysisusingtheA533BmaterialmodelareshowninFigures5-13through5-18.AsintheA302Bmodelanalysis, thelimitingcaseistheaxialflaworientation.

Application oftheASMEAppendixXcriteriaindicates thattheminimumUSElevelisbelow10ft-lbs,whentheA533Bmaterialmodelisapplied.5.3.2PlateG-307-4AnalysisTheresultsoftheplateG-307-4analysisusingtheA533BmaterialmodelareshowninFigures5-19through5-24.AsintheplateG-8-1analysis, usingthismaterialmodel,theminimumUSElevelisbelow10ft-lbs.5.4SummaryofConditions AnalyzedTheresultsoftheelastic-plastic fracturemechanics assessment areshowninTable5-1.Asexpected, theA302Bmaterialmodelyieldsthemostconservative results.Asdiscussed inSection4,0,theA302Bmaterialmodelbestrepresents theNMP-1beltlineplates.TheASMEflawstability criterion ismoreconservative thanthe0.1inchflawgrowthcriterion fortheNMP-1plates.Basedonthesecalculations, ithasbeenconcluded thattheNMP-1platesG-8-1andG-307-4mustbemaintained above23ft-lbs.45 l,<ei Table5-1MinimumUpperShelfEnergyLevel(AxialFlaw)forNMP-1PlatesBasedontheASMEDraftAppendixXEvaluation CriteriaforServiceLevelsAandBMinimumUSE(Ft-Lbs)PlateG-8-1'-8-1G-307-4G-307-4MaterialModelA302BA533BA302BA533BFlawGrowthof0.1in.Criterion Ji<Jo.i<1013<10FlawStability Criterion P'1.25P,23<1023<1046

10Ft.-Lbs.NINEMILEPOINTUNIT1PLATEQ-8-1A302BModef/L-T.

Orientation/Axial Flaw,20Ft100090030Ft.-Lbs.80004700C800C600C0400E300Cl200l~j40Ft.-Lbs.60Ft.-Lbs.60Ft.-Lbs.70Ft.-Lbs.80Ft.-Lbs.90Ft.-Lbs.10000.000.200.400.600.801.00Deltaa(In.)100Ft;Lbs.~J-Applied at0.1ln.Figure5-1Evaluation UsingCriterion forFlawGrowthof0.1in.forPlateG-8-1ModelledUsingA302BMaterialModel(AxialFlaw)47

~TI1t 10Fk.-LbI.NINEMILEPOINTUNIT1PLATEQ-8-1A3028Model/7-L Orientation/Circum.

Flaw,20FtLbs100090030Ft.-Lbs.80040Ft:Lbs.700aCO8OOC600C0400E300Cl7200/60Ft:Lbs.80Ft.-Lbs.70Ft.-Lbs.80Ft.-Lbs.90Ft.-Lbs.100100Ft.-Lbs.0.000.200.400.800.801eooDeltaa(In.)~J-Applied at0.1ln.Figure5-2Evaluation UsingCriterion forFlawGrowthof0.1in.forPlate6-8-1ModelledUsingA302BMaterialModel(Circumferential Flaw)

~~

10Fl..Lbe.NINEMILEPOINTUNIT1PLATEG-8-1A302BModel/L-T Orientation/Axial Flaw100090030Ft.-Lbs.80040Ft.-Lbs.700tlOBOOI600C0400E300Cl720060Ft.-Lbs.BOFt,-Lbs.70Ft.-Lbs.80Ft.-Lbs.90Ft.-Lbs.10000.000.200.40O.BO0.801.00TearingModulus100Ft.-Lbs.T-Applied Figure5-3J-TMaterialandJ-TAppliedCurvesforPlateG-8-1ModelledUsingA302BMaterialModel(AxialFlaw)49 10 10Ft.-Ltt~.NINEMILEPOINTUNITIPLATE0-8-1A302BModei/7-L Orientation/Ciroum.

Flaw100090030Ft.-Lbs.80040Ft.-Lbs.700cCO800Ic600C0C400E~eet0300A60Ft.-Lbs.80Ft.-Lbs.70Ft.-Lbs.80Ft.-Lbs.20090Ft.-Lbs,100100Ft.-Lbs,0.000.200.400.800.801.00TearingModulusT-Applied Figure5-4J-TMaterialandJ-TAppliedCurvesforPlateG-8-1ModelledUsingA302BMaterialModel(Circumferential Flaw)50

NlNEMlLEPolNTUNlT5PLATEG-8-'lA302BModel/L,>>T Orientation/Axial FlewOnsetof--Accumulation

--1.26'Accum.

FlawInstab.pressurePressure20001900180017001BOO1500COCO1400130012001100100001020304050BO7080UpperShelfEnergy(Ft.-Lbs.)

Figure5-5Evaluation UsingCriterion forFlawStability forPlateG-8-1ModelledUsingA302BMaterialModel(AxialFlaw)51 I

NINEMILEPOINTUNIT'IPLATEG-8-IA302BModel/7-L Orientation/Circum.

FlawOnsetof-"Accumulation

--1.25'Accum.

FlawInstab.PressurePressure40003500SOOOICLIa2500COIOIL,20001500100001020Sosoeo7080UpperShelfEnergy(Ft.-Lbs.)

Figure5-6Evaluation UsingCriterion forFlawStability forPlateG-8-1ModelledUsingA302BMaterialModel(Circumferential Flaw)52 b~5UV 10Ft.-Lbs.NINEMILEPOINTUNITIPLATE0-307-4A302BModel/L-T Orientation/Axial Flaw100090D30Ft.-Lbs.8OO40Ft.-Lbs.700tCO8OOC600C0ttt400E3004200le/~60Ft.-Lbs.80Ft.-Lbs.70Ft.-Lbs.80Ft.-Lbs.90Ft.-Lbs."'foo0D.DDD.2D0.400.8D0.801.00Deltaa(In.)100Ft.-Lbs.~.J-Applied at0.1ln.Figure5-7Evaluation UsingCriterion forFlawGrowthof0.1in.forPlate6-307-4ModelledUsingA302BMaterialModel(AxialFlaw)53 5~

10Ft.-LbI.NINEMILEPOINTUNIT1PLATEG-307-4A302BModel/T-L Orientation/Clroum.

Flaw10009OO30Ft.-Lbs.80040Ft.-Lbs.700C8OOIC800aa400E300Q2001000/:Jle'II'Ili60Ft.-Lbs.80Ft.-Lbs.70F!.-Lbs.80Ft.-Lbs.90Ft.-Lbs.100Ft,-Lbs.0.000.200.400.600.801.00Deltaa(In.)~J-Applied at0.1ln.Figure5-8Evaluation UsingCriterion forFlawGrowthof0.1in.forPlateG-307-4ModelledUsingA302BMaterialModel(Circumferential Flaw)54 r

10Ft.-Lbs.NINEMILEPOINTUNIT0PLATEG-307-4A302BModel/L-7 Orientation/Axial Flaw100090030Ft.-Lb@.80040Ft.-Lbs.700ceooC600c04006300Cl60Ft.-Lbs.eOFt.-Us.70Ft.-Lbs.80Ft.-Lbs.20090Ft:Lbs.10000.000.200.400.800.801.00TearingModulus100Ft.-Lbs.T-Applied Figure5-9J-TMaterialandJ-TAppliedCurvesforPlateG-307-4ModelledUsingA302BMaterialModel(AxialFlaw)55 1rfl4 10Ft.-LbaNINEMILEPOINTUNIT1PLATEQ-307-4A302BModel/T-L Orientation/Circum.

Flaw100090030Ft.-Lbs.80040Ft.-Lbs.700eCOeooC600Co400E300Ch60Ft.-Lbs.eoFt.-t.bs.

70Ft.-Lbs.80Ft.-Lbs.20090Ft.-Lbs.10000.000.200.400.800.801.00TearingModulus100Ft.-Lbs.T-Applied Figure5-10J-TMaterialandJ-TAppliedCurvesforPlateG-307-4ModelledUsingA302BMaterialModel(Circumferential Flaw)56

NINEMILEPOINTUNIT1PLATE6-307-4A302BModel/L>>T Orientation/Axial Flaw-~-Onsetof--Accumulation

--1.26'Accum.

FlawInstab.PressurePressure200019001800170018001500COII14001300120011001000010203060eo7080UpperShelfEnergy(Ft.-Lbs.)

Figure5-11Evaluation UsingCriterion forFlawStability forPlateG-307-4ModelledUsingA302BMaterialModel(AxialFlaw)57

NINEMILEPOINTUNITIPLATEG-307-4A302BModel/T-L Orlentatlon/Circum.

Flaw-~-Onsetof--Accumulation

--1.26'Accum.

FlawInstab.PressurePressure400035003000I02500COIOILaCL20001500100001020304050507080UpperShelfEnergy(Ft.-Lbs.)

Figure5-12Evaluation UsingCriterion forFlawStability forPlateG-307-4Modelling UsingA302BMaterialModel(Circumferential Flaw)58

~t' 10FL-Lbs.NINEMILEPOINTUNIT1PLATEC-8-1A533BNtodel/L-T Orientation/Axial Flaw,20Ft500030Ft.-Lbs.400040Ft.-Lbs.aCl3000Icc0Cti2000EICL1000t/I50Ft.-Lbs.60Ft.-Lbs.70Ft.-Lbs.80Ft.-Lbs.90Ft.-Lbs.100Ft.-Lbs.0.000.200.400.600.801.00Deltaa(In.)~J-Applied at0.1ln.Figure5-13Evaluation UsingCriterion forFlawGrowthof0.1in.forPlateG-8-1ModelledUsingA533BMaterialModel(AxialFlaw)59

~~~~I~I'~~

10Fl.-Lbe.NINEMILEPOINTUNIT1PLATEG-8-1A633BModel/L-T Orientation/Axial Flaw20FtLbs60004000L.:30Ft.-Lbs.40Ft.-Lbs.CCO3000ICC02000EICl50Ft.-Lbs.60Ft.>>Lbs.70Ft.-Lbs.80Ft.-Lbs.100090Ft.-Lb@.00TearingModulus100Ft.-Lbs.T-Applied Figure5-15J-TMaterialandJ-TAppliedCurvesforPlateG-8-1ModelledUsingA533BMaterialModel(AxialFlaw)61

10Ft.-Lbs.NINEMILEPOINTUNIT1PLATEG-8-1A633BModel/7-L Orientation/Clroum.

Flaw---20Ft.-Lbs.60004000L:.30Ft.-Lbs.40Ft.-Lbs.C3000Cc0Ct$20006Ch50Ft.-Lbs.80Ft.-Lbs.70Ft.-Lbs.80Ft.-Lbs.100080Ft.-Lbs.100Ft.-Lbs.12TearingModulusT-Applied Figure5-16J-TMaterialandJ-TAppliedCurvesforPlateG-8-1Modelled'singA533BMaterialModel(Circumferential Flaw)62

NINEMILEPOINTUNIT1PLATEG-8-1A6338Model/L-7 Orientation/Axial Flaw-~-Onsetof"-Accumulation

--1.26'Accum.

Flawlnstab.PressurePressure6000450040003500COCLIa3O0OIOI4250020001600100001020306oeo7080UpperShelfEnergy(Ft.-Lbs.)

Figure5-17Evaluation UsingCriterion forFlawStability forPlateG-8-1ModelledUsingA533BMaterialModel(AxialFlaw)63

~~NINEMILEPOINTUNITIPLATEG-8-IA633BModel/Y-L Orientation/Clroum.

Flaw-0-Onsetof"-Accumulation

--1.26'Accum.

FlawInstab.PressurePressure10QeQ.~oCCON~coQ5QCL10203040soeo7080UpperShelfEnergy(Ft.-Lbs.)

Figure5-18Evaluation UsingCriterion forFlawStability forPlateG-8-1ModelledUsingA533BMaterialModel(Circumferential Flaw)64

'I

~'10Ft.-LbI.NINEMILEPOINTUNIT1PLATEQ-307-4A5338Model/L-T Orientation/Axial Flaw600030Ft.-Lbs.400040Ft,-Lbs.cCO3000cC02000ELe0ICl50Ft.-Lbs.60Ft.-Lbs.,70Ft.-Lbs.80Ft.-Lbs.10000t1'I90Ft.-Lbs.100Ft.-Lbs.0.000.200.400.600.801.00Deltaa(In.)~J-Applied at0.1ln.Figure5-19Evaluation UsingCriterion forFlawGrowthof0.1in.forPlateG-307-4ModelledUsingA533BMaterialModel(AxialFlaw)65

10Ft.-Lbs.NINEMILEPOINTUNIT1PLATEG-307-4A533BModel/T-L Orientation/Circum.

Flaw,20Ft600030Ft.-Lbs.400040Ft.-Lbs.CCO3000Itc0CI200080OCl1000//I50Ft.-Lbs.80Ft.-Lbs.70Ft,-Lbs.80Ft.-Lbs.90Ft.-Lbs.100Ft.-Lbs.0.000.200.400.800.801.00Deltaa(In.)~J-Applied at0.1ln.Figure5-20Evaluation UsingCriterion forFlawGrowthof0.1in.forPlateG-307-4ModelledUsingA533BMaterialModel(Circumferential Flaw)66

~~

e~'0Ft.-Lbs.NINEMILEPOINTUNIT'IPLATEG-307-4A533BModel/L-T Orlentatlon/Axial Flaw.20Ft60004000L:30Ft.-Lbs.40Ft.-Lbs.ctO3000ec0sga42000EICl50Ft.-Lbs.60Ft.-Lbs.70Ft.-Lbs.80Ft.-Lbs.100090Ft.-Lbs.00TearingModulus100Ft.-Lbs.T-Applied Figure5-21J-TMaterialandJ-TAppliedCurvesforPlateG-307-4ModelledUsingA533BMaterialModel(AxialFlaw)67

10Fl.-Lbe.NINEMILEPOINTUNIT1PLATEG-307-4A6338Model/7-L Orientation/Ciroum.

Flaw60004000eL.:30Ft.-Lbs.40Ft.-ibs.tCO3000IC:c0Ctt2000EClCl50Ft.-Lbs.60Ft.-Lbs.70Ft.-Lbs.80Ft.-Lbs.100090Ft.-ibs.0012TearingModulus100Ft.-Lbs.T-Applied Figure5-22J-TMaterialandJ-TAppliedCurvesforPlateG-307-4Modelled'singA533BMaterialModel(Circumferential Flaw)68

~~)

NINEMILEPOINTUNIT1PLATEG-30T-4A533BModel/L-T Orientation/Axial FlawOnsetof--Accumulation

--1.25'Accum.

FlawInstab.PressurePressure6000460040003500COCL3000QLe250020001600100010203040507080UpperShelfEnergy(Ft.-Lbs.)

Figure5-23Evaluation UsingCriterion forFlawStability forPlateG-307-4ModelledUsingA533BMaterialModel(AxialFlaw)69

NINEMlLEPOINTUNITIPLATE6-307-4A633BModel/T-L Orientation/Circum.

Flaw-R-Onsetot"-Accumulation

--1.26'Accum.

FlawInstab.PressurePressure10QCL~6Ic05th2cog5Q010203050507080UpperShelfEnergy(Ft.-Lbs.)

Figure5-24Evaluation UsingCriterion forFlawStability forPlateG-307-4ModelledUsingA533BMaterialModel(Circumferential Flaw)70 (way>x'

6.0 SummaryandConclusions

Theelastic-plastic fracturemechanics analysesperformed haveshownthattheaxialflawisthelimitingorientation.

TheNMP-1A302MbeltlineplatesarebestmodelledusinganA302BJ-Rcurvemodel.DuringtheSeptember 30,1992,meeting,theNRCindicated reluctance inaccepting the0.8L-TtoT-Lconversion withoutadditional statistical evidence.

Workiscurrently beingconducted todemonstrate thatanL-TtoT-Lconversion factorabove0.65isappropriate fortheNMP-1beltlineplates.Nevertheless, asshowninTable6-1,thereisatpresentsufficient marginagainstductilefractureusingtheRG1.99(2) genericmodelwitha0.65conversion factor.Since1972,theT-Lorientation hasbeenrequiredbyASMEandusedinthenuclearindustryforanalysisofpressurevessels.The50ft-lbscreening criterion isalsoevaluated basedontheT-Lorientation.

However,amoreconsistent approachwouldbetoevaluatetheaxialflawusingL-TCharpyUSEdata,andtoevaluatethecircumferential flawusingT-LCharpydata.AsshowninTable6-2,whentheappropriate orientation isconsidered, themarginbetweentheminimumallowable USEandthepredicted actualUSEatEOLisontheorderof38ft-lbs.ThismarginofsafetyisinadditiontothesafetyfactorsappliedtotheASMEAppendixXequations.

Therefore, ithasbeenconcluded thattheNMP-1vesselissafeintermsofductilefracturefailurethroughEOLforServiceLevelAandBloadings.

TheLevelCandDloadingsarecurrently beinganalyzedandwillbereportedtotheNRCinaseparatereportinthenearfuture.71

Table6-1Comparison oftheMinimumUpperShelfEnergyLevel(AxialFlaw)forNMP-1PlatesBasedontheASMEDraftAppendixXEvaluation CriteriaforServiceLevelsAandBwiththeRegulatory Guide1.99(2)ModelEstimates PlateMaterialModelFlawGrowthof0.1in.Criterion Jt<Jo.tFlawStability Criterion P~>1.25P,MinimumAllowable USE(Ft-Lbs)forAxialFlaw(L-TOrientation)

RGL99(2)Model'T-L Orientation)

MinimumUSE(Ft-lbs)Prediction atEOLG-8-1G-307-4A302BA302B1313232342.640.0'enericmodelappliedwithoutplant-specific data72

Table6-2MinimumUpperShelfEnergyLevelMarginsforNMP-1PlatesforServiceLevelAandBLoadingsPIateMaterialFlawModelOrientation MinimumAllowable USEFt-LbCharpySpecimenOrientation Conservatively Predicted CharpyUSEat~EDL'-LbMargingt-L+bsG-8-1A302BAxial23L-T65.642.6G-8-1A302BCircumferential

<10T-L42.6>32.6G-307-4G-307-4A302BA302BAxialCircumferential 23<10L-TT-L61.640.038.6>30.025EFPYexposureprojected forEOLin2009.TheRG1.99(2) model,withoutplant-specific data,wasusedtoconservatively estimatetheminimumEOLUSElevels.73 4C.+1A4'4

7.0 References

[ASME80]ASMEBoilerandPressureVesselcode,SectionIII,"RulesforConstruction ofNuclearPowerPlantComponents",

July1,1980[ASME92]ASME,DraftCodeCaseN-XXX,"Assessment ofReactorVesselswithLowUpperShelfCharpyEnergyLevels",Revision11,May27,1992.[CE90]"NiagaraMohawkPowerCorporation NineMilePointUnit1ReactorVesselWeldMaterials",

ReportNo.86390-MCC-001, ABBCombustion Engineering NuclearPowerCombustion Engineering, Inc.,Windsor,Connecticut, June,1990.[DI76]Dieter,G.E.,Mechanical Metallurgy, SecondEdition,McGraw-Hill, 1976.[EA91]Eason,E.D.,Wright,J.E.,Nelson,E.E.,"Multivariable ModelingofPressureVesselandPipingJ-RData",NUREG/CR-5729, May,1991.[FR92]Freyer,P.,Manahan,M.P.,Presentation toProjectFERMI,"PlantLifeExtension Technology:

Non-Destructive ReactorMaterials Embrittlement Monitoring UsingPositronAnnihilation",

May,1992.[HA82]Hawthorne, J.R.,Menke,B.H.,Loss,F.J.,Watson,H.E.,Hiser,A.L.,Gray,R.A.,"Evaluation andPrediction ofNeutronEmbrittlement inReactorPressureVesselMaterials",

EPRI/NP-2782, preparedforEPRI,December, 1982.[HA90]Hawthorne, J.R.,Hiser,A.L.,"Influence ofFluenceRateonRadiation-Induced Mechanical PropertyChangesinReactorPressureVesselSteels",NUREG/CR-5493,March,1990.~[HI83],.Hiser,.A.L.,

Fishman,D.B.,"J-RCurveDataBaseAnalysisofIrradiated ReactorPressureVesselSteels",preparedforEPRIDecember, 1983.[HI89]Hiser,A.L.,Terrell,J.B.,"SizeEffectsonJ-RCurvesforA302BPlate",NUREG/CR-5265, January,1989.[JOY91]Joyce,J.A.,Hackett,E.M.,"Extension andExtrapolation ofJ-RCurvesandTheirApplication totheLowUpperShelfToughness Issue",NUREG/CR-5577, March,1991.[MA85]Manahan,M.P.,"Procedure fortheDetermination ofInitialRTNinCaseswhereLimitedBaselineDataareAvailable",

November, 1985.74 (awlc*ky~x>k4

[MA85a]Manahan,M.P.,Quayle,S.F.,Rosenfield, A.R.,andShetty,D.K.,"Statistical AnalysisofCleavage-Fracture Data",Invitedpaper,Conference Proceedings oftheInternational Conference andExhibition onFatigue,Corrosion

Cracking, FractureMechanics, andFailureAnalysis, SaltLakecity,December2-6,1985.[MA90]Manahan,M.P.,"NineMilePointUnit1RT~Determination",

FinalReportfromMPMResearch&Consulting toNMPC,September 28,1990.[MA91]Manahan,M.P.,"NineMilePointUnit1Surveillance CapsuleProgram",

NMEL-90001,January4,1991.[MA91b]Privatecommunication, M.P.Manahan(MPMResearch&Consulting) toJ.Helm(Columbia University),

"Physically BasedUpperShelfFractureModelforFerriticPressureVesselSteels",January,1991.[MA92]Manahan,M.P.,Soong,Y.,"Response toNRCGenericLetter92-01forNineMilePointUnit1",June12,1992.[McFRAC]Manahan,M.P.,et.al.,"Statistical AnalysisMethodology forMechanics ofFracture",

FinalreporttoBattelle's Corporate Technology Development Office,1984.[MTEB81]NRCBranchTechnical PositionMTEB5-2,"Fracture Toughness Requirements",

Revision1,July,1981.[OD86]Odette,G.R.,Lombrazo, P.M.,"TheRelationBetweenIrradiation Hardening andEmbrittlement ofPressureVesselSteels",Proceedings ofthe12thASTMSymposium ontheEffectsofIrradiation onMaterials, 1986.[RG1.99]Regulatory Guide1.99,Revision2,"Radiation Embrittlement ofReactorVesselMaterials",

May,1988.[TEL92]Telephone conference regarding NMP-1lowUSE,NRCstaff,NMPClicensing andengineering staff,MPMResearch&Consulting, August22,1992,[USE92]USEŽVersion2.0CodePackageforElastic-Plastic FractureMechanics Assessment ofNuclearReactorPressureVessels,MPMResearch&Consulting, 1992.75 1'PI1