ML17219A262

St Lucie I Steam Generator Allowable Tube Wall Degradation.

ML17219A262
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Site:	Saint Lucie
Issue date:	10/31/1986
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ST.LUCIEISTEAMGENERATOR ALLOWABLE TUBEWALLDEGRADATION CENC-1747 October19868612~503+

50003358gg212pgpggQCK05pgRp TABLEOFCONTENTSPAGESUMMARYANDCONCLUSIONS II.INTRODUCTION

......III.GEOMETRY.......IV.DEVELOPMENT OFHYDRAULIC LOADS~~~~~~~~~~~~~~123A~IntloductlOn~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~B.Loss-of-Coolant Accident1~Thermal-Hydraulic Model2.Assumptions

.......3.Operating Conditions

.........

Results............................................

C.MainSteamLineBreak5781.Thermal-Hydraulic Model............................

92.Assumptions

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

93.Operating Conditions

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

~~~t]OV.4.ResultsDEVELOPMENT OFMECHANICAL LOADSA.SafeShutdownEarthquake

......B.LOCAandMSLBImpulseResponseC.Piessure......~~~~~~~~~~~~~~~~~~~~~~~10~~~~~~~~~11~~~~~~~~~~~~~~~~~~~~~~~~~12VI.ALLOMABLE STRESSDETERMINATION A.Allowable StressesforTubes...........................

13VII.LOCAPLUSSSESTRUCTURAL ANALYSISA.FiniteElementModelB.LOCAAnalysis....VIII.MSLBPLUSSSESTRUCTURAL ANALYSISA.Loadings~~~~~~~~~~~~~~~~~~~~~~~~~14~~~~~~~~~~~~~t~~~151.Hydraulic FlowLoads...............................

172.SSELoads.....~~~~~~~~~~~~~~~~~~~~~~173.PressureLoads.....................................

17 PAGEB.FiniteElementModelC.StressResults1.Hydraulic Flow2.SSE..3.Pressure..D.Resultant StressesIX.NRCSTAFFCRITERIAFORMINIMUMACCEPTABLE TUBEWALLTHICKNESS X.ALLOWABLE TUBEWALLDEGRADATION

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

XI.REFERENCES 1718181819202122APPENDICES A.STRUCTURAL GEOMETRYANDFINITEELEMENTMODEL....-....'..

A,O8THERMALHYDRAULIC MODELANDRESULTS...-B.OC.LOCA+SSESTRUCTURAL ANALYSISRESULTS...-.............

C;0D.RESULTSFROMEPRI/CEPROJECTS144.E.EVALUATION PERNRCSTAFFCRITERIA..~~~~~~oD~P~~~~~~~E~OF.FATIGUEEVALUATION

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

F.O11

I.SUMMARYANDCONCLUSIONS Thisanalysisestablishes theallowable tubewalldegradation fortheSt.LucieIsteamgenerator basedontherequirements ofReg.Guide1.121(Reference 1).Theanalysisconsiders thetubeloadingsduetonormaloperation, LossofCoolantAccident(LOCA),MainSteamLineBreak(MSLB)andSafeShutdownEarthquake (SSE).Allowable tubewalldegradation isestablished inaccordance withtheASMECodeSectionIIIallowables (ormargins)consistent withtheprovisions ofReg.Guide1.121.Thefollowing summarizes theresultsofthisanalysis:

A.Thecriteriaonnormaloperating differential pressureofReg.Guide1.121controlstheallowable tubewalldegradation forallregionsofthetubebundlewiththeexception oftheupperre-gions(abovetheuppermost supportplate)ofTubeRows117through120which.aregovernedbyLOCA+SSEloads.B.Theallowable tubewalldegradation is63Kforallregionsexceptfortheregionsabovetheuppermost supportplateforfollowing TubeRows:a)TubeRow117-59%b)TubeRow118-60Kc)TubeRow119-61%d)TubeRow120-62%C.Theallowable tubewalldegradation determined fromconsideration ofNSLBandSSEisaminimumof66Kandisnotcontrolling.

II.INTRODUCTION Theanalysispresented hereinisperformed toestablish themaximumallowable tubewalldegradation fortheSt.Lucie1SteamGenerator tubespertherequirements ofNRCReg.Guide1.121.Theresultsofthisstudywillbeusedasthebasesforasteamgenerator technical specification changetothetubepluggingcriteria.

Thisreportaddresses therequirements ofNRCReg.Guide1.121formaximumallowable differential pressures duringnormaloperation andaccidentconditions aswellastheASMECodeSectionIIIAppendixFrequirements forfaultedloadconditions ofLossofCoolantAccidents (LOCA)plusSafeShutdownEarthquake (SSE)loadsandMainSteamLineBreak(MSLB)plusSSEloads.Duringtheperformance ofthisanalysis, consideration isgiventothetubesupportplatemodifications whereintheouterrimsandlugsoftheuppertubesupportplateswereremoved.Thisallowstheupperportionofthetubebundletomovelaterally throughagapandcon-tacttheshroudduringaLOCAevent.Tuberows87through140areevaluated inthisanalysiswiththeshorterrowsconsidered tobenon-controlling duetodecreasing LOCAforcesresulting fromshorterhorizontal spansanddecreasing momentarmlengthsbetweenthepointofloadapplication andthesupportlocations.

III.'GEOMETRY TheSt.LucieIsteamgenerator tubebundleisconstructed from0.75inchO.D.X0.048inchwalltubesandissupported bygridtype(eggcrate) tubesupportsintheaxialflowregion.(SeeFigureA.1.).Thetubebundleisrestrained inthecross-flow regionbyseveraldifferent typesoftubesupports.

Theverticalstraightlegportionofthetubesisrestrained bytwopartialeggcrates andtwodrillplates.Thehorizontal tubespaninsidethe90arc10inchradiibendsissupported byslottedverticalstripscontaining.

horizontal stripsweldedintoalignedslots.Thissupportarrangement providesverticalin-planeandout-of-plane motionrestraint andisaninte-gralpartofthediagonalsupportswhichextendacrossthe10inchradiusbendofalltubes.ThissupportassemblyisuniquetotheCEdesignand,duetoitsfirmattachment totherestraining I-beams,providesexcellent lateralaswellasverticalsupporttothetubes.Pastmodifications tothetwodrillplatesupportsconsisted ofre-movingtheirouterrimsandpartoftheattaching lugsleavingagapwherebylateralmotioncanoccur.Theplateswere"staked"byexpanding atubesleeveintothetubeattheplatejunctionatninelocations onthelowerplateandfiveplacesontheupperplate.

IV.DEVELOPMENT OFHYDRAULIC LOADSA.IntroductionALoss-of-Coolant Accident(LOCA)producesararefaction wavewhichpropagates atthespeedofsoundawayfromthebreaklocation.

Astherarefaction wavepassesthroughthetubesinthebendregionofthesteamgenerator, itimpartsalateralpressureloadingonthetubebundle.Thepressureloadingonaparticular tubeispropor-tionaltothepressuredifferenceactingbetweenthemidpoints ofthebends.Fluidfrictionandthecentrifugal forcesgenerated asthefluidnegotiates thebendsalsocontribute tothelateralloadingonrthetubebundle.Thenetforceonaparticular tubeisthealgebraic sumofthepressure,

friction, andcentrifugal forces.AMainSteamLineBreak(MSLB)producesatransient pressureloadingonsteamgenerator internals.

Thepressureloadingresultsfromtherelativeratesatwhichthesecondary fluidleavesadjacentregions.Ingeneral,theblowdownratefollowing amainsteamlinebreakde-pendsuponthesteamgenerator

geometry, thesecondary

pressure, the.secondary mass,andthenozzlearea.Thethermal-hydraulic responseoftheprimary(LOCA)andsecondary (MSLB)systemsduringthepostulated accidents isanalyzedusingCombustion Engineering's CEFLASH-4A computercode(Reference 4).CEFLASH-4A isaone-dimensional, two-phase, thermal-hydraulic codewhichcalculates thetime-dependent behaviorofthefluidstatere-sultingfromaflowlineruptureoranoperational transient.

Thesolutionproceedsbynumerically integrating themomentumequationappliedtotheflowpathswhilemaintaining massandenergybalancesinthenodes.Heattransferbetweentheprimaryandsecondary fluidsiscalculated.

Thecodecontainsitsownwaterpropertytablesand'numberofuser-selected options.CriticalflowmodelsincludetheMoody,theHenry-Fauske, andthemodifiedHenry-Fauske/Moody correlations.

Frictionfactorsmaybeuser-specified orcode-calculated toconformtoinitialconditions.

ThefrictionfactorsmaybeconstantorRey-noldsNumberdependent duringthetransient.

Available two-phase multipliers includethoseofMartinelli-Nelson andThorn.Themomen-tumfluxterm,whichaccountsforthepressuredropresulting fromspatialchangesindensityandvelocity, maybeselectively includedinthemomentumequation.

Finally,bothhomogeneous (mixedphase)andheterogeneous (separated phase)nodesmaybechosen.In1982,anexperimental program,sponsored inpartbytheElectricPowerResearchInstitute, wascompleted inwhichthehydraulic load-ingpredicted bytheCEFLASH-4A codewascomparedwithexperimental measurements forafivetubemodelofasteamgenerator experiencing aLOCA.Thisanalytical/experimental comparison providedvalidation ofthecode'sthermal-hydraulic modelingandrecommended that-forLOCAeventswhichfocusonthesteamgenerator internals

-thebreakbemodeledasclosetothesteamgenerator asisphysically possible(Reference 5).B.Loss-of-Coolant Accident1.Thermal-H draulicModelIthasbeenestablished thatmaximumhydraulic loadingonasteamgenerator tubeinthebendregionisrealizedduringadouble-ended guillotine breakinthecoldlegpipe.Inthepresentanalysis, thebreakismodeledatasteamgenerator primaryoutletnozzle(Refer-ence5).Foracoldlegbreak,thehydraulic forcesonasteamgen-eratortubeinthebendregionareillustrated inFigureB.l.The pressureforceresulting fromtherarefaction waveisdefinedbythepressuredifference betweenthemidpoints ofthebends(atthe45positions) actingoverthe-cross-sectional flowareaofthetube.Thetime-varying averagefluidfrictionforceisbasedonthemassflowrateinthecenterofthehorizontal spanandisdefinedby:2fWvL'2~0gwhere,fisthefrictionfactor,dimensionless Mistheflowrateinthetube,ibm/secvisthespecificvolume,ft/ibmDisthetubeinsidediameter, ft.Listhelengthbetweenthemidpoints ofthebends,ft.gistheuniversal gravitational

constant, 32.17ft-ibm/lb

-sec2fTheresultant horizontal component ofthecentrifugal forcesexertedbythefluidinnegotiating thebendsisneglected inthepresentanalysis.

Ouringaloss-of-coolant

accident, thesecondary systemremainsin-tactexceptforheattransferbetweentheprimaryandthesecondary fluids.Thusrepresentation ofthesecondary systems(twosteamgenerators) intheLOCAthermal-hydraulic modelisremote.However,thefinitespeedofpropagation andmultiplereflections oftherare-factionwavewhichtravelsthroughtheprimarysystemrequireanaccurateandcompleterepresentation oftheprimarysystem.Theentireprimaryflowsystemisdividedintoanetworkofnodesand flowpathsasisshowninFiguresB.2.Inaddition, itisnecessary toprovidemorerefinedmodelingforthesteamgenerator thatistheclosesttothebreaklocation(FigureB.3).Thethermal-hydraulic detailshowninFigure8.3pertainstoeachofthreetuberowsmodeled(tuberows8140,114and88).NodeandflowpathnumbersnotincludedinFigures8.2andB.3arenotutilizedintheLOCAthermal-hydraulic model.Thefollowing assumptions areutilized:

a.Allnodesarehomogeneous.

b.Theproperties ofwaterandsteamforestablishing initialandboundaryconditions aretakenfromReference 6;c.Adouble-ended guillotine breakopeningtimeof0.020secondsisassumedfortheruptureofone30-inchcoldlegpipeatonepri-maryoutletnozzle.Thisbreakopeningtimeisbasedonareac-torcoolantsystemasymmetric loadanalysis(Reference 7).d.Thetwo-phase pressuredropiscalculated byfirstspecifying constantliquidphasefrictionfactorsbasedontheMoodydiagram(Reference 8).Thesefrictionfactorsarethenmultiplied bytheThorntwo-phase flowfactor(Reference 9)storedwithinthecode.e.Themomentumfluxtermisincludedforallinternalflowpaths.f.FlowthroughthebreakismodeledusingthemodifiedHenry-Fauske/Moody criticalflowcorrelation.

g.Adischarge coefficient of0.7isassumed(Reference 10).h.Itisassumedthat15%ofthesteamgenerator tubesareplugged.3.0eratinConditions TheLOCAeventoccursatfullpowerwiththefollowing plantoperating conditions (Reference 11):~Pr1marPrimaryTemperature In,FPrimaryTemperature Out,FPrimaryFlowRate,ibm/sec.PrimaryPressure,

.psia598548193672250~Seconder Saturation Pressure,psiaFeedwater Temperature, FFeedwater FlowRate,ibm/sec.886430.916414.ResultsThenetforceonatubeineachofthethreetuberowsmodeled(tuberows8140,114and88)asafunctionoftimeispresented inFigures8.4,8.5and8.6,respectively.

Itcanbeseenthat,foreachofthesetuberows,themaximumhydraulic loadingisrealizedatapprox-imately0.015seconds.Thenetforceasafunctionoftimeforeachtuberowisinputintothelineardynamictransient analysis.

Thepressureinthemiddleofthebendsasafunctionoftimeforeachtuberowispresented inFigures8.7through8.12.TheaverageflowrateinFlowPath42asafunctionoftimeforeachtuberowispresented inFigures8.13through8.15.

C.MainSteamLineBreak1.Thermal-H draulicModelPreviousanalysesofamainsteamlinebreakforawiderangeofoperating conditions anddifferent steamgenerator geometries indi-catethatpeakpressureloadsonsteamgenerator internals arereal-izedateitherzeroorlowpoweroperation.

Peakpressureloadacrossthetubebendregionisrealizedatzeropercentpower.Our-ingthemainsteamlinebreak,therapiddepressurization ofthesecondary fluidanditsacceleration towardthebreaklocationareunaffected bytheprimarysystem.Therefore, theMSLBthermal-hydraulic modelfeaturesonlydetailthatpertainstothesecondary system,asisshowninFigure8.16.NodeandflowpathnumbersnotincludedinFigureB.16arenotutilizedintheMSLBthermal-hydraulicmodel.Thefollowing assumptions areutilized:

a.Allcalculations aremadeassumingnoslipbetweenthesteamandthewater.*b.Propertiesofwaterandsteamforestablishing initialandbound-aryconditions aretakenfromReference 6.c.Adouble-ended guillotine breakopeningtimeof0.001secondsisassumedfortheruptureofthe34-inchsteamlineatthesteamoutletnozzle.

d.Thetwo-phase pressuredropiscalculated byfirstspecifying constantliquidphasefrictionfactorsbasedontheMoodydiagramReference 8).Thesefrictionfactorsarethenmultiplied bytheThorntwo-phase flowfactor(Reference 9)storedwithinthecode.e.FlowthroughthebreakismodeledusingtheMoodycriticalflowcorrelation (Reference 12).f.Themomentumfluxtermisincludedforallinternalflowpaths.g.Adischarge coefficient of1.0isassumed.3.0eratinConditions TheMSLBeventoccursatzeropowerwiththefollowing plantoperat-ingconditions (Reference 11):~Seconder Saturation

Pressure, psiaFeedwater Temperature, FFeedwater FlowRate,ibm/sec.0%Power37509004.ResultsThepressuredifference acrossthetubebendregion(P9-P6)asafunctionoftimeispresented inFigureB.17.Themaximumpressureloadof28.6psiisrealizedatapproximately 0.075seconds.ThepressureinNodes9and6asafunctionoftimeispresented inFig-uressB.18andB.19.TheflowrateinFlowPath7(inthemiddleofthetubebendregion)asafunctionoftimeispresented inFigureB.20.10

V.DEVELOPMENT OFMECHANICAL LOADSA.SafeShutdownEarthuakeTheprojectspecification forSt.LucieI,Reference 3,statesthatthesteamgenerator assemblyshallbecapableofwithstanding amaxi-mumseismicloadingequivalent to0.5g'sinbothhorizontal andver-ticaldirections appliedsimultaneously throughthesteamgenerator supports.

Theevaluation ofthisloadingcondition isaccomplished withanANSYS(Reference 13)two-dimensional finiteelementmodelwhichisdescribed inSectionVIIandisutilizedforbothSSEandLOCAevaluations.

SSEstressesareobtainedbytheapplication ofastaticloadequivalent toa+0.5gacceleration inthehorizontal andverticaldirections simultaneously.

Twoverticalloadcasesareconsidered sinceSSE+deadweightloadingsareanalyzedtodetermine theworstcondition.

HoweverLOCAstressesarenormallycontrolling, therefore, SSEstresslocations areevaluated attheworstLOCAstresslocation.

B.LOCAandMSLBImulseResonseTheLOCAorMSLBaccidentproducesanexternally appliedimpulsetothesteamgenerator causedbythefluidescapingfromitsrespective loop.LOCAimpulsestresseshavebeencalculated foraunitofsimi-lardesignandhavebeenfoundtobeonly+2.0ksi.(Reference 14).However,duetoremovalofthedrillsupportplates,lugsandouterrim,gapsarepresentwhichallowimpacting betweenthedrillplatetubeassemblyandthebafflewhichincreases tubebendingstresses.

Avalueof+4.0ksiisusedinthisanalysisbasedontheparametric evaluation ofagapcondition presented inAppendixC.Mainsteamlinebreakimpulseloadingsareconservatively estimated at+6.0ksiforuseinthisanalysisbasedonaworstcaselocation11 inthecrossflowregionforaunitofsimilardesignand0.75"0.0.X0.008"walltubes.C.PressureOuringtheLOCAeventatubeissubjected toanetpressureforcewhichproducesanaxialforceintheverticalstraightportionofthetube.Withthesecondary pressureremaining approximately constantduringtheLOCAeventat815psia,a"blow-off" differential pressurestressisdetermined-basedonthispressureandtheprimarypressureatthetimeofmaximumLOCAstresses.

Theprimarypressure, isob-tainedfromthe"CE-FLASH" programresultsandis1336psiaatthetimeandlocationofmaximumtubestress.Thepressuredifferential forMSLBisconservatively takentobe2250ps'hisisbasedontheoperating primarypressurewiththeas-sumptionthatthesecondary pressurehasdecayedtozero.12 VI.ALLOWABLE STRESSDETERMINATION The'basisfortheallowable stressesusedinthisanalysisisSectionIIIoftheASMECodeforNuclearPowerPlantComponents.

ValuesforS,yieldstrengthandultimatestrengthatoperating temperatures aretakendirectlyfromtheappropriate tablesintheCode.A.Allowable StressesforTubesTheultimatestrengthfortheSB-163InconeltubingisS=80.0ksi0u,atthemaximumoperating temperature of600F.AppendixFofSectionIIIgivesthemembranestressallowable forthefaultedconditions considered inthisreportas:orSb=0.7SS=56.0ks>Themembraneplusbendingallowable isSbf.0.7S+bendMherefisafunctionofcross-sectional shapeaswellastheratioofmembraneandbendingstressestoyieldstress.Aninteraction curve,FigureE.4isshowninAppendixEfora63percentdegradedtubeandahealthytube.TheratioofmembranetoyieldstressfortheLOCAanalysisisap-proximately 0.2~Therefore, fisequalto1.44andtheallowable stressintensity is:S.I.=S+b=1.44(56)=80.6ksi13

VII.LOCAPLUSSSESTRUCTURAL ANALYSISA.FiniteElementModelAnANSYSfiniteelementmodelisdeveloped forthetubebundlegeome-trydescribed inSectionIII.FigureA.2givesaschematic oftheportionofthetubebundlethatis-modeledforthisanalysis.

Themodelisatwo-dimensional representation ofthetubebundledevel-opedbycombining thetubesinRows87through140into19lumpedparametric rowsasgiveninTableA.l.Themodelincludesthepor-tionofthetubebundleabovetheuppermost fulleggcratesupportwithallthetubesthatarecapturedbythe.lowerdrillplateplusthefirstthreetuberowsthatareinsidethelowerdrillplate.ThefiniteelementmodelisshowninFigureA.3.Thetubesaremodeledastwo-dimensional beam,ANSYSStif3,elements.

Themassdistribu-tionofthedrillplatesisrepresented bylumpedmass,ANSYSStif21,elementsatthenodeswhichareatthedrillplatelocations.

Theeffectofthedrillplatesismodeledbycouplingthenodesinthe"x"horizontal direction atthedrillplatelocations.

Thehori-zontalportionofthetubesarecoupledtotheverticalsupportswithonedimensional spring,ANSYSStif14,elements.

Theverticalsup-portandbatwingareasandmomentsofinertiaareweightedforeachrowbasedonthenumberofverticalsupportsandbatwingsinthatrow.Thefiniteelementmodelhas723elementsofthetypeslistedabove.)Themodelboundary"conditions areasfollows:Thetubesatthefulleggcratearefixedinthe"x"and"Y"direction.

Thetubesarefixedinthe"x"direction atthepartialeggcratelocations.

The.7inchgapwhichisdescribed inAppendixCismodeledusingtheANSYSgapmoduledescribed inSection3.2.14ofReference

13.

Theanalysisisperformed forhealthyInconeltubes-.75inchO.D.X.048inchwallthickness.

Thetubeelementsareattributed anequiv-alentdensity,p,formulated from:P=(1/AT)(PT AT+PSAS+CPfAf)wherep=Densityoftubematerial=.305lbs/inp=Density-of fluidintube=.0261lbs/inpf=Density-of displaced fluid=.0045lbs/inAT=Areaoftubematerial=.106inAS=Insideareaoftube=.336inAf=Outsideareaoftube=.442inC=Virtualmasscoefficient Avirtualmasscoefficient ofCm=1.7isappliedtothetubes.Theresulting densitybecomes.4157lbs/inandthecorresponding massdensityis.001077,lbs-sec/in.Astructural dampingof2Xofcriti-caldampingisusedforthesmalldiameterpipinginaccordance withAECRegulatory Guide1.61.(Reference 14).Themodulusofelasticity is28.8X10psiforthetubesand26.3X10psifortheverticalsupportsandbatwings.

ThefluiddynamicloadsversustimeforTubeRows140,114and88aregiveninFiguresB.4,B.5,andB.6.Thesecorrespond withModelRows19,10,and1.Theloadsgivenintheabovefiguresareforasingletubeineachrow.Therefore, theseloadsmustbescaledandcombined15 forthefiniteelementmodel.Thisisdonebyassumingthattheloadsvarylinearlybetweenthethreerowssothatthetotalloadonanymodelrowisthetotaloftheinterpolated singletubeloadmul-tipliedbythenumberoflumpedtubesinthatmodelrow.Themodeltuberowloadsareappliedasconcentrated forcesasafunctionoftimeinthehorizontal direction actingatthecenternodesoftherespective horizontal tubespans.TheanalysisistheANSYSReducedLinearDynamicAnalysis.

Theresultsofthisanalysisaretheele-mentstressesandloadsasafunctionof.time.ThemaximumstressinthestresstimehistoryforeachmodeltuberowisshowninTableC.l.Thelocationofthemaximumstressforeachtuberowisindi-catedinFigureC.l.Atimehistoryplotofthemaximumbendingstressformodelrowsllthrough15isgiveninFigureC.2.ThesestressesareatNodes259,284,309,334and359ofelements184,183,185,187and189,respectively asshowninFigureC.3.FigureC.4givesapl'otofthedisplaced geometryatthetimeofthemaximumLOCAstresses.

FigureC.5givesatimehistoryplotofthedis-placements ofNodes19,469and259.ThelocationofNodes19and469areshowninFigureC.1,whileNode259isgiveninFigureC.3.FigureC.6givesatimehistoryplotofthedisplacements ofNodes457and459.ThelocationofNode959isgiveninFigureC.l,while459isshowninFigureC.3..TheSSEseismicloadingisevaluated usingthesamemodelasfortheLOCAanalysis.

TheSSEloadsareappliedasaccelerations of-1.5Gvertically and+.5Ghorizontally.

Theresulting SSEstressesatthelocations ofmaximumLOCAstressarealsoshowninTableC.l.16 VIII.MSLBPLUS-SSESTRUCTURAL ANALYSISA.~Loadina1.HdraulicFlowLoadsThetubesinthecross-flow regionaresubjected toanexternalflowinducedpressuredropduringtheMSLBevent.Detailsoftheanalysisprocedure andresultsarepresented inSectionIVandAppendix8,respectively.

Themaximumpressuredropacrossthebendregionofthetubebundleis28.6psi.ThispressureloadisfromFigureB.17andisappliedasaconstantloadingwhichisconservative.

Theloadingimposedonthehorizontal spanofeachtubeisbasedontheassumption thattheforceactingisproportional totheratioofanindividual tubeprojected areatothetotalcross-flow tubeareaofthebundle.2.'SELoadsAsdefinedinSectionV.A,0.5gloadswereappliedsimultaneously inthehorizontal andverticaldirections withdeadweightloadsconsid-eredintheverticaldirection.

3.PressureLoadsThetubedifferential pressureisassumedtobe2250psiandisbasedontheassumption thatthesecondary pressurehasdecayedtozero.B.FiniteElementModelTheFEMisdescribed inSectionVIIwithdetailedgeometryplotspresented inAppendixA.Briefly,themodelisplanarwithRows87through140modeledin19lumpedparameter rows.Mostofthemodel17 rowshave-three actualtuberowswithcombinedmass,stiffness, andloadings.

Selection ofverticalstripareasandmomentofinertiasareweightedsothatthedynamiccharacteristics ofthetubebundlearenotaltered.C.StressResultsThemaximumbendingstressesduetoMSLBflowloadsare9.77and9.95ksiatnodelocations 212and217,respectively.

Thiscorresponds toTubeRows110,111and112whicharetheshortestrowsattachedtoallthreeverticalstrips(seeFigureA.2).Node217islocatedattheleftverticalstrip/tube positionwhile212isinthe90degreebendregion.2.SSETheseismicstressesatNodes212and217occurring atthetimeofmaximumNSLBstressesare7.6'and6.3ksi,respectively.

Thevalueof7.6ksiisalsothehighestSSEstressforanylocationinthebundle.Tabulated valuesareincludedinTableC.lforallmodeltuberows.3.PressureThestressesduetoadifferential pressureof2250psiintheaxial,hoop,andradialdirections are:i=7.7ksiPR.2t18 PR.~hoop=i=15.3ksitoradial=P=02D.Resultant StressesTheresultant stressintensity isdetermined bycombining NSLBandSSEstressesusingthesquarerootofthesumofthesquares(SRSS)methodplustheadditionofpressurestresses.

01[(9.77)+(7.6)]=12.4ksi8Node212<2=[(9.95)+(6.3)]=11.8ksi8Node217Theworstcasestress,a1,isusedtodetermine amaximumallowable TWDof66percent.Theprocedure fordetermining thisvalueispre-sentedinArticleE.lofAppendixE.1oaxialradial=12.4+7.7-0=20.1<1.44(.7)Su=80.6ksi19 IX.NRCSTAFF.CRITERIAFORMINIMUMACCEPTABLE TUBEWALLTHICKNESS 1.Tubeswithdetectedacceptable defectswillnotbestresseddur-ingthefullrangeofnormalreactoroperation beyondtheelasticrangeoftubematerial.

2.Thefactorofsafetyagainstfailurebyburstingundernormaloperating conditions isnotlessthanthreeatanytubelocationwheredefectshavebeendetected.

3.Crack-type defects,thatcouldleadtotuberuptureeitherduringnormaloperation orunderpostulated accidentconditions wouldnotbeacceptable.

ThesecriteriaarefromReference 1andareinadditiontothefault-edallowables ofSectionIII.FigureE.lpresentstheminimumre-quiredthicknesses fortubesbasedontheabovecriteria.

'20

X.ALLOWABLE TUBEWALLDEGRADATION Astructural-thermal hydraulic analysisoftheSt.Lucie1SteamGenerator tubebundleindicates thattheallowable TWDiscontrolled, foramajorityoftuberowsbyNRCReg.Guide1.121criteria.

Amaximumallowable TWDof63percentisfoundtobeacceptable foralltuberowswiththeexceptions of117through120abovethetopdrillplate.Themaximumallowable TWDfortheserowsiscontrolled bythefaultedcondition, LOCA+SSE,andis59,60,61,and62percent,respectively.

Theprocedure forfaultedloadsevaluation ispresented inAppendixE.Atabulation ofLOCAandSSEstressesisgiveninTableC.lofAppendixC.Itshouldbenotedthat97.9percentofalltubesmeettherequirements ofReg.Guide1.121for63percentTWDwithonly178tubesor2.1percenthavingallowable TMD'sof59-62percent.Afatigueanalysisofadegradedtubeispresented inAppendixFwiththemaximumusagefactor,U,fora63percentdegradedtubedeter-mined*tobezero.'21 XI.REFERENCES 1.NuclearRegulatory Guide1.121,"BasesforPluggingDegradedPHRSteamGenerator Tubes".2.ASMEBoilerandPressureVesselCode,SectionIIIforNuclearVessels,1986Edition.3.Engineering Specification forSteamGenerator Assemblies forSaintLucieNo.1,Specification No.19367-31-2, Revision13.4."CEFLASH-4A, AFortranIVDigitalComputerProgramforReactorBlowdownAnalysis",

SA-78-223, J.M.Betancourt, Combustion Engi-neering,Inc.,Department 489,June1973.5.EPRINP-2652,"LoadsonSteamGenerator TubesduringSimulated Loss-of-Coolant AccidentConditions",

ProjectS144-1,FinalRe-port,November1982.6.1977ASMESteamTables,C.A.Meyer,etal.,ThirdEdition,ASME,NewYork,N.Y.,1977.7."ReactorCoolantSystemsAsymmetric LoadEvaluation Program-FinalReportforCalvertCliffs1and2,Millstone 2,Palisades andFortCalhoun",

June30,1980.8.Moody,L.F.,"Friction FactorsforPipeFlow",Transactions, ASME,Vol.66,1944.9.Thorn,J.R.S.,"Prediction ofPressureDropDuringForcedCircu-lationBoilingofMater",Int.J.Heat&MassTransfer, Vol.7,1964.22 10.Combustion Engineering ReportCENPD-252-P-A, "Blowdown AnalysisMethod",July1979.11.FloridaPower5LightCompany,JNS-MCI-86-161, LetterfromJ.E.NoabatoJ.N.Mesthoven, October3,1986.12.Moody,F.J.,"MaximumFlowRateofaSingleComponent, Two-Phase Mixture",

ASMETransactions, February1965.13.ANSYSEngineering AnalysisSystem,FiniteElementComputerPro-gram,Revision4;1,March1,1983,JohnA.Swanson,Ph.D.14.AECRegulatory Guide1.61..15.Combustion Engineering, Inc.,CENC-1264 (Revision 2),"Analysis toDetermine Allowable TubeMallDegradation forPalisades SteamGenerators",

March30,1976.16.Combustion Engineering, Inc.,CENC-1170, "Analytical ReportforFloridaPower5LightCompanySteamGenerator",

December, 1971.17.DesininbPhotoelasticit

,R.B.Heywood,1952.23 APPENDIXASTRUCTURAL GEOMETRYANDFINITEELEMENTMODELFIGUREA.1STEAMGENERATOR ELEVATION VIEWFIGUREA.2UPPERTUBEBUNDLEGEOMETRYFIGUREA.3ANSYSFINITEELEMENTMODELTABLEA.1FINITEELEMENTMODELTUBEDATAA.O JQhQj,FIGUREA.1STEAMGENERATOR

-ELEVATION VIEWA.l

BAFFLE.BATWING317510"RADIUS(TYPICAL)

ROW14022DRILLPLATETYPICALSLOTS-ROW116ROI1110-tOW9022DRILLPLATEROW66P.EC26.5P.E.C.ROW56OW2825.5TOPFULLEGGCRAITE SUPPORTFIGUREA.2UPPERTUBEBUNDLEGEOMETRYA.2 TABLEA.lFINITEELEMENTMODELTUBEDATAMODELROWTUBEROWSROWNO.TOTALNO.OFTUBESMOMENTSOFINERTIA(IN)AREA(IN)687888990919293949596979899100101102103104666564636460~6261626160596059585756571951871851801771701.27731.22491.21181.17901.15941.113520.6719.82219.6119.0818.76218.0210556106.10754165..1.080817.4910108109110ill112113114115116535251505150494847105152194.6878.99561.270711.1316.11220.564A.4 MODELROMROWNO.TUBEROWSTOTALNO.OFTUBESMOMENTSOFINERTIA(IN)AREA(IN)1213141516171819117118119120121122123124125126127128129130131132133134135136137138139140464544434241403938373635343330292827282920171291129120102877449~--=-~9.5960.8450.7860.7271.6681.5699.4847.3210.058959.64613.67412.7211.76610.8129.2227.8445.194.954A.5 APPENDIXBTHERMAL-HYDRAULIC MODELSANDRESULTSFIGUREB.1HYDRAULIC FORCESONATUBEFIGUREB.2LOCATHERMAL-HYDRAULIC MODELFIGUREB.3FIGUREB.4FIGUREB.5LOCATHECAL-HYDRAULIC MODEL(STEAMGENERATOR DETAIL)CLOCANETFORCEVSTIME(TUBEROW8140)LOCANETFORCEVSTIME(TUBEROW8114)FIGUREB.6LOCANETFORCEVSTIVE(TUBEROW888)FIGUREB.7AVERAGEPRESSUREBETWEENNODES39AND40VSTIME(TUBEROlllj140)FIGUREB.8AVERAGEPRESSUREBETWEENNODES44AND45VS.TDK(TUBEROM8140)FIGUREB.9AVERAGEPRESSUREBETtJEENNODES39AND40VSTIVE(TUBEROW8114)FIGUREB.10AVERAGEPRESSUREBETWEENNODES44AND45VS.TIME(TUBEROWf114)FIGUREB.11AVERAGEPRESSUREBETWEENNODES39AND40VSTIME(TUBEROWII88)FIGUREB.12AVERAGEPRESSUREBETWEENNODES44AND45VSTIME(TUBEROWPP88)B.O

APPENDIXB-(CONTINUED)

THERMAL-HYDRAULIC YODELSANDRESULTSFIGUREB.13FLOWRATEINFLOtlPATH42VSTIME(TUBERONt'!140)FIGUREB.14FLOWRATEINFLOWPATH42VSTIYE(TUBEROW//114)FIGUREB.15FLONRATEINFLOWPATH42VSTIME(TUBEROWf88)FIGUREB.16Y~LBTHERYAL-HYDRAULIC YODELFIGUREB.17PRESSUREDIFFERENCE VSTIME(Pg-P6)FIGUREB.18PRESSUREINNODE9VSTIYEFIGUREB.19PRESSUREINNODE6VSTIYENFIGUREB.20FLOWRATEINFLOt'/PATH7VSTIYE FIGUREB.1HYDRAULIC FORCESONATUBEHorizonta FNt=F<<Ff(F-F)epcx1cx2'NeF=hP~APFfncx1BreakLocationB.2 FIGU8.2LOCATHERMAL-HYDRAULIC MODEL21222023251917D35Secondary

)2D34Secondary f11261627301533-3433ll12131ll910131215353131262930S.1.TankflS.1.Tankf2S.1.Tankl3FillSystoa5636NHode323229FlerPath 1

FIGUREB.3,LOCATHERMAL-HYDRAULIC MODELSTEAMGENERATOR DETAIL)PrimarySystem41l24344404142l3453946462547472119184949162417142629B.4

f~,ImIIh,"FIGUREB..TubeRo,'LOCANETFORCEf.~II~I4VSTIMEhIi140I!I80206050i.540O3020llm~WII;'i.!Iflt~Imatm~JW~AI'~=-I~~m~~~mm~W~~j'fI"='-llII~~It,~m--I~~ltIlmIIII~ImIIIIltiWI~Wl!I~IIIltNIII~~m~10II-10I~I-20h0,I~m,IIIIhh[I':"1ijjm~!(IIlltI'082,.0P4)l006!,0;~III~=*[hI,'I;'I0!10,01I120.]40.160.180Time,SecondsI~/mj'I="I'~'mjt!fjj;jt'ljj~Img'tm"I,):I!jlPW,(,mii'!Ž!'IIImI~ml'f,hm IL.~II":~~I>>FIGURE8.5}LOCANETFORCE,VSTINEIIh'>>*[807060~=~(~=h:It~I~~'\m~>>III~',4Il(I>>'}I:.I,~I~ITube'ow8114I~III'11't~>>~~~II'f,I>>~>>~l~I~*,~h->>Itl,h't(~>>t~I'I,lJ5Ig7>>~(I)OSO~~I(IJI50403Q>>II~I>>1-20~:,.',I10h~~ItmIIItt-10I',}-20iI0.020.040.06O.h8(0.I~~110-"0.;(ii}'i}'(0.14,'0.16-.'0; 8IO..Time,-SecandgIh~hl(I~~Ii(t)(~-'I}II),;;tI~lhI~I III~8070I~I'IIsII.~Ii~sIII'f~II*I'srjIIIs;IsIf1'TubeRow'888---iI;,I.-tI'FIGURE8.6IOCANETFORCEVSLIME*I~I'~~.I.I...I.:I~;'iI':iiii..':

i"II.al~ratIIIIII+~t+L1sI=~~~~t~=*~IsIII~.It~',l'.t~I~~~IIIIIf~I~I~I6050';~l,lIIIIIIII~.I'IW~~o!II~iQJt40302010II,II~.iI;ttIIII'tI.sIIilI'sIIsII~I~I}IIIiIl.IIIi=.~I~I!Il-10I-20~~"0.020.04'";0.06

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(.'~~n(Lli()))1800r117001600.lI1500~II')).I.,--'-!14001I'1300.>>i.,2200I....I..2100I'20001.,I;1900nI<<I~~'I';~I<<-~li~>>>>I'1ln)!,I<<I~~~~I~I~.~~>>'sr~~rn'<<iIi.~n~~s:sslI~~'r>>iI<<IlIs<<~lYls'1Il~.nAG<<I,<<')~>>I>>~~~1'I;,1;n\i~.I>>l,,I<<II',I(Isn;i));~(I'I>>n~If1nlr'VERIl'if.'1~ill))>>sil;isfn~~r'>>II=I'T:"11s,PRESSn>>r~nn~1Il1'IIlllewjI:!~l:sliIsIsIInss~~I1)>>i~~f(Ilr~>>snssIFIGUREB.7.,UREBETWEEN:NODES 39ANTubeRod~~<<swn!;i',~~islln>>s~>>~r(<<n~-II1r(>>I'1~n(~Isir~'~<<'i~rl1I.~~II,'(~ll1>>,n'I40VsInI~TIME<<n~~I~1".;I~s)'Isii~~fIs1!i>>I',"'...+I.l..~.;1Is(s',.I'IlsIin)>>1~~nr>>n1.!1IIlnr!jill>>~>>r1InI!I;.~'-,lI-r1':I'Y~I~I~>>II~(I:I.iIIsTr~~Irnll>>II~!l1!nrl1~~I,.n<<IIIre,1.!III~I~>>il'<<.I~~n~>>~.I,(I>>~>>r!iI,-'i(IInIsnl1.jI,:I'I!i~(f~~1~Inn'i":..I..nn,:.1Inln~~li'1)1'I~sl".,Ir~~II),'1I>>!in,'-n!r1I1Inst~rn<<~~r'r>>~~~.'1,.I~=.;I..1~II.0.020;0410.06'.sOo!'0.IIl~~s!-:in~10i0In)((me.!(I1>>iCOlldS,s1r1~(n1I'120.14';160.'18;0.InI20;II~'T>>I~"n<<1s:I':>>~Iis"i<<<<t~n>>I>>sl!<<'

s~s~s,~~tC~t~i~I'1.t.'),Ii.;AVERAG~'isiFIGUREB.:8IUREBETWEEN'NODES

~~I!!?~I~~I~~~~~~~III~~!1~!4t44AND45rsil;;s~VTIME~IJTis.stst~~,if,lsI'I~sts~tst'Ii~~Iss'I....I~II22002100I1900.I"1800~~Igl~CLQstgCl.IglIggl~{j)O1700.1600I'500i1400~.,~~2000{sIt~~iIitsIsssI'ts)Is~sJ't~~tIsiII~s~~~gsitte]sIggt{~{s~I'I':i:Ig.'II!IIIll~,Il~sit-~itI~~I?II~.I""=~Isist{Ilst~II",?~"'sgi,'lIIiill<<i<<iI".l!I~I~-gs;IlIIi!:!sgs'lsIL'Isfg,I;I.;I"Ia-.il<<J~+I~.t~lg'g>>I,s,II.it.l:IIJstI~IIs~t~t~I.~~tJ?-Js.IsgsstJlIsItsIts~~I~s.st~tJITub'eRow8140sstsst~sggsP~s~I~asiiIs~~s~IsIIsss~gtt~I{g,jt"ilI!~s~tsIsIsI'.',I,t"J~II~~~s~,,I-~sskit~IliltI',Ii'ltglsss1gI,~.I'~"sli'.il't'Igi,'-I'sI';fig<<s'IIIIII.-jl;'I'll',ill::;I:?Itstt,i~t'l':.sIslsi1300'I~I'.";I~~~ss"II'rt"s~I~.IIsi.-~~I~II'~~Js~ti,I~sIIIIs(sts.~I~~-lII~sI~~I's'lg8~0.1Isr",~iisjil~'liiti;0.020.040.060.000.120.140.160.18'.20:JI;I'I'ime.

Sei';on<<-'~~ItI'IrIIII!sl~Iss'!I(!rss~IiillssI!'ll kJ 2200210020001900gl16001600<<~I'II~14001800~I~1700j'-efOg.4!1~~~I~ei.fi!~,~~1"II"I~~II~I4~iIced'.I1'I;,-'II'I~~~rf.lcI.!!Ge,eII<<4ijl",'~~I~"'I'fcjF4'll;4I'4!!IlIil,!leIc"~~4'ii!li~'Iili,I~'I'Ilie~III,:,Ii1.IIII~~~4~vEkn~~~I'Iiil~1'IIIII1~~Ill~~I)II,'-I~I!,4'.II'~1-II.IjclclIIII~~~II!IIIi;,IfPRES4'IGURk8;9UREBETMEEN'ODES 39ANITubeRow'If!114~~~Ililt!II~IIII~~11I~Ii!'4'cl~~44clII'IIIItIi'el<<!II.ll4I40V.I'TiNE~~~~1I~~~4I.':I:'elI:fl~I~;I'W,'l~~~~eirlI'~'I4I~1-IIIIiil!llI!II!,IilII~III~I,114,lLlCl'I41~1~I~II*.I~I~\~,I~~II1'ji~'iI~1','llei..-Ice,,I*I*1I"4~~~l4I~4e.I~II'~~~~I~I~IIIlI'.IF.Iei~ii1'r.;il'II~I~~III*'l~I11'"I~'I'.Illci~Iie"II~II,l,eIce~i}I~I~IIII,'leIII,~I-ee'4~4I'I4~'IIIII,II~1i"~4~'~fi~ec1300II0.020.04,0.060.I~1~I~life"1~~80.iI.I~~~I~l.if'tI~I0IO;1el1II'4i~!~!l.160.12.0.14'0Ije.;...Time4I.-:econdI,I~8;0.'I1~Iei~4II1!'.,:Iil~~II,4IIIII'1'!Ic<<,4Ile'IiIcI,"I~1te4IIIIIlI

~~~~~~2200II,es'tI~eI'-!I.,~'.lee~Is'i!;I~~~IsAGVERI~'ITubeRowfj114I(!FIGUREIB.10.PRESSURE BETllEEN'ODES 44ANbsI45VfTIflEsI~IleI~,~I;;.s~I,eI.IIe.'.Isrs~I.~ee~~~'"*eeIeI"i.:I"!:sl~~s..l.!.e;s.I:-210020001800ICL~~seIC!IllC!i017001600Is('-150s140I~*130s1900s!II~sset's'.IIItI1IIIIIs'fes}IsI!~',I'llsts.sse~Isc~sssesji'~tseI':III-~I'!'~:le~li'~I~ei.',I:~eseelrI~sf~...!r!;;sjf)j:.i.'i!I',I~~~;".',il.:

ei!I}*i,lit,'ll.i.,~lj(se~~se,'sflit,,Ie!,Iee!!lf,hl!i'-iIrstI'e-tei'Ii'I~T,:.Il."I:~use~f;;II~~~s~II~sf~~eI"IhlIelII~IIeII~i~I.I'(,:(,II~lretteess'ffIse-ssIf~.I~.~~~'r~~e~iced~II~~IfI'II':.s':";I'.-';-

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~lt~iIIIIIt4VE'PRESURE'FIGURE8;11BETNEENNODES139'Nll AOTheTIHEIIEIVICLCU~4QJMEI/IUlI33EO17001600=15001402200I2100I2000I1900-11300tIlI-Il4~tl4IT~I~~,IIm~I~1*tt~~4E~/44~tl~"~~,1'I"';":.I).4~,Ig44t'.IIII'ubeRowP88IIiII4~4f~t~-~I~hlI~I)t)t444I~*Itl1IT'~Ih~I-I4130jlvIII~I4~Il~~I0.020.040.060.080.1'00.120.140.160.180.2044I~=thllileecon~~'il~j,TT~II~'hIIlE!Wh:jtii~

~Iill'~I>>'II"2200I;.*;~I210020001900IOIIhC7CL~>>illSCJO1800III1700I}.j160I150II140~~>>~I~\'b*I.'li'.'IlII~Il>>II!'IIiI~~iI;I;Iiitlii:lliII~rij'lil>>'~II.ItliltI:i'};I,iI,I'.It,I}"'Ir>>I'I~.~I~~~'II~'.ASPERA.'Ill'I.'~PRESSURE' 1'll'ttIb;iiill~>>II'-i!IIIIjfjtIliI1'tII;tllIII!i:IiI::IiilIb'.;.:I.;~I:-'.,:.'1l:~1j'i-,FIGUREB.12:"I',':BETLIEENNODES44.AND45VS~ba'ssl.TubeRow~kvtII}!:I~'I'.I.'Ij"~Ir~1i'.~~*~t~~IIII'biIIIibI~t~I1I~~~IIbk~li~~II~'II>>~IIIII*IITII}ti'~~l~II-~*ITIMEII"',I,~I~~~~~I1III~tII~III:IIt;I.lI~,~~I,~I~I~~'i:,ljl.;,klbI>>vIill:',,}I~1~tI~IIIk~Ii;II<<ll~~Ilt~=I'I!I:tIjI;I>>.llrIb'Il~~ii'"I~~II1I<<'i:"'.IrI>>~,I~I.IIIII'.'riIl'llb~IIII'~I~~b~ll-.I,.'j~II~-Ib~~~I~I}:,::~i>>b~*~~~~~~klbI}b'I.130I~II~I~~I}~iI>>IIIiII}l~"i"~,.I~".I>>~II'l',Jl}~I>>!l':~iI'.lII'IiI~I.I'~~'"':iv'blI0.020.040.060.0o'.1I>>~~0.140.160.18'"0.20*1t~tII'.I:i>>I~~'-"I'l.I~!}"II~b~~tivl~I'I~vlII~I~;i",]lime,.SecoriI~Isj!I~,t'aiI}I>>Ilt~>>Iif~libl)iII,>>II~~1'1~-.

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E0, rmIa~'~~*ai:tIii~~aI~i~'I~Ii'lait~~r:laIi~~aaIt:i.FIGUREB.l4FLOW'ATEIf)FLO>fPATHTubeRow8i114mII'I;I\tI.'~iiir~il~,jIi~tt~~42VSI~ITIMEi..iIil'I.'i!tIII~1~'t~III',r~f':itl.,~aI'alma"iIJii'11~Iti)Itl~a~~a.I~I~~tiI0~i,I'ImaI~~~I='at;~f~I'llI~Ia~~~I,Ifii~IIII~,~'!IDQtC/l~~E~Cl'~JOltttlitCC0Lt-~I'al-t.-'..i-,1~IIII60000Il)30000'0000!aIaII1IIIIilI0I1,UI1~~[,liat01:I!'it~~tIIII.,'ail1mfIail..'t-I..II~IiI~',t!t~~~I~II'IiJii',1I~'!-.IaiIIil'III.Uit~,iiI'f~m0al-0~f~If00.020.040.060.08D.IDII~)':im=~-II1iI~0.121~III~I00i~0.140.160.180.20'1~Iilat~~1~~m~IIII~~I~iIITime',Si'":cohdsIaim.t;I~t~I~I'!I1fIf'~IUi:iii~It~ttf~liitl

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FIGUREB.16MSLBTHERMAL-HYDRAULIC MODELSecondary System11IFloePath2424232019191010111213lSB.17

~II~~III4~....j.'."HSLB~4--LBENt)IFIGUREB.r17EGIONPRESSUREDIIIIFEREN~III.-I,E9S~-I~IiIJI4..(..4~I',.jiI4iiI'I~I~4I4IfI"~~'4~~IfrilJII'IllI'*/I'ltI"44IIsfII~ji;"l~ICJOOCQ~$~Q400~IID302520I~*'It~Ii~siilI,i~4~,~~I~~"~44II'IIISr'ii,,I'II~I'IIsl,'I.~~~I~I~II~j-IlltClS-CJS-CL15I10I~5'll'444-10'4I,~O.!20.IIIIf,hlff,tillji"IITjme,reconI4I~!4Ii,llIl~I'i~i'its,4I L14~ee~~~~V~1~1~1~111eIct51~CLlO~IAIll920900QQO860840i~~I~1iII~~1~"!e+Ie~~ilail'ljij)>j~III11~~~1!~ee~'lfit~~;.i!II)j~~',!~ii'Ijl1III1(!'e1e1*~!je.jieelilieie~I'*~~I:i':"'-i"FIGUREB.18,I11PRESSUREINNODE9ItS~*I~'.i!11'1.'!i-~I1lfiljI:11~~~1I,'1TIj1E1~1~~1'ee'Ie:I!~I~If~1"1'~=~11Ie'eI~e~~*i,i:I1t'~'e~i~1j~j.i11~j'I'll~,~'~l1'i~,~~j:1.-l.~1~~IIi1,pieeIlf,1li)1~II'eIji,jji'IIlII~~~I~1'=I~~~1~ilef1lI'I,'~~~'1')1--:I-~1lIel:.e'11:eiejIt~820800I14eee11~.I-"iI'~~~I~11~e~1~i'I1'1ge'i,i;~~~~11.~eei.'111.ijij"I~jI'feejele7801~.l.I;jI,)"jl.l'.2~0.1~1~eII~~tii~i~lIIII~~jj",,*I~'jI1~~11~0.6~~11I1I!I0.8ime',.econ'dI~ItII~'!j1~...I,~11~l111~II,eelI1!l~,!jjjjili.~1Ii~4~1eI1'ej1<<lI~ll~~el~ifeil~~IjI1II I~III~~~I1IiCUgMOgS-Icj6CL--920.900-.8808684}-82I'l."80-78II1II~I~I~I~~1I1,';II*~I~rIf~,.*:I1'I~I,'iIIItI(~-}~ip;.}.'-,IlTTII;'liIII~(II~',PR1IIIII:.ipIiI~!I11)ii'}II~~~~ijII.!IJII~'.1,~~~I~~lar1t!FIGURE0.19ESSUREINRODE(!6VSTINEI~1-I~~I~~I~~I1~*II~*I~~~~I~I~'I,la~!II.~~i".II}':,I~VIIV~~I~I1I~~,'!ii~=I~~Iaal~I~~I~I'avi}"IIltI'I'I~I'III~}~~fIIL;e'I~-I1~'III~VI'I'IllIII~la~~II.I"I(",I,ltI~Il(~I,,I~I~1111~~II,I*llj}.'I}IIIaaI~Iji'II~'I!I!I,IIla~IafI~~I~~~~I~~~I:!3,$!I~!I'II~II~II11I,~I~IItI~ii-}/vaaIIII1~I~IIIVt1'Iii}a~Iliaa-~'II~~~aa!IIII'I0.24:lj0.60.8}'.'0~~~It~II1~ii.'vaa'I~

0000070000~'46000050000CQ~rt444CX3000020000~4110000I"'4'10='=I~44II!40000oE4I'II4III~i:~444I4'I444~\~~~44~s*~IIII~4~",!!';[tI-:(ii4Is.II~~I~4.I:IIi41~IsiIT~I~Iil44!4I44~4II~-I4-lti;4~4"~.4lt44~IFLOWI4I~I~IS44IJT*I4~~~41=I4~,")~II~I*4~'i\~Ii!'4il4~~4444<<4494I4I~I=4I;4>>4li'f.14li.4~~I~'II'ilI4I4II~~II,';;>>Ii't'441IlIIII~}IIiilaI~~~4IFIGUREB.20RATEIttFLOWPATH7VSTItlE!4~4>>~I1'.i44li144~tll4I'";,~tt4~~I~~~I4Ilt~Iilsi~ITII.s'~~4rt~,III,Ii"",I'>>II4Ij444[!IIIit~4~I4.4IsI!lii:,','4~I~I,)1'r4']~4IIh1'"44~~~~It4'4~I44,;"jH~*4'.4i~4I~4l~~II4>>,I~4I.II,.s.11IIstI~~4..It~I4~'I4l>>';.*)IiillI14~~~ill.i:."-is~is'II'lls!ItI4~I,~*I'~Isl44~~+I4~~0.2'.4rr~I4~4\~I1hi.i.>>I,'si~iI,il4ill!IsI'-I~:0.Ij:~stItl4440.84Sego'ri*I,"Time;4,"II]..~~1I!,~IsI~J~itiI~II4~4~*I~l4l:,sl~~4~~~4I444~~~ APPENDIXCRESULTSOFLOCAANDMSLBSTRUCTURAL ANALYSISARTICLEC.lDISCUSSION OFTUBESTRESSASAFUNCTIONOFGAPWIDTHTABLEC.lLOCAANDSSESEISMICSTRESSESFIGUREC.1LOCAMAXIMUM-STRESSLOCATIONS FIGUREC.2TIMEHISTORYOFLOCABENDINGSTRESS;NODES259,309,3345350FIGUREC.3GEOMETRYATMAXIMUMSTRESSLOCATIONFIGUREC.4LOCADISPLACED GEOMETRYFIGUREC.5TIMEHISTORYDISPLACEMENTS; NODES19,2575469FIGUREC.6TIMEHISTORYDISPLACEMENTS; NODES4595759FIGUREC.7MAINSTEAMLINEBREAKDISPLACED GEOMETRYWITHMAXIMUMSTRESSLOCATIONS FIGUREC.8PARAMETRIC EVALUATION OFBENDINGSTRESSVS.GAPWIDTH ARTICLEC.1DISCUSSION OFTUBESTRESSASAFUNCTIONOFGAPMIDTHAsdiscussed earlier,amodification toSt.Lucie1uppertubesupportplateswasperformed in1978toremovetheouterrimandsupporting lugs.Basedonphotographs takenatthistimeagapcondition forsteamgenera-tors"A"and"B"existedbetweentheouterportionoftheseplatesandtheremainder ofthesupportlugwhichisweldedtotheshroud.Thisgapvariedfrom0.7to1.3inchesatthattime.Nofurtherdataisavailable pres-ently,henceaparametric evaluation ofthegapcondition forLOCArarefac-tionloadingswasperformed withtheresultsillustrated inFigureC.8.Themaximumstressoccursforagapcondition of0.70"whichisusedinthisanalysis. Agapofabout1.15inchesappearstoproducethesmalleststress.Inconclusion, onecanstatethatthegapcondition hasthepoten-tialforchangingthemaximumLOCAstressesby25-30percent.Therefore theLOCAimpulsestressobtainedfromananalysisofasimilarsteamgener-ator.withrigiddrillplatesupportscanbeamplified byafactorof2.0,aswasdoneinthisanalysis, andshouldyieldconservative results. TABLEC.1LOCAANDSSESEISMICSTRESSESMODELROWMAXIMUMLOCAREDUCEDLOCASSESTRESSKSINODE123567891011121314151617181925.924.020.819.918.716.816.218.822.223.737.7234.628.721.920.721.922.422.123.019.4318.015;614.9314.0312.612.1514.116.6517.7828.2825.9521.5316.4315.5316.4316.816.5817.252.85.74.94.74.54.33.71.37.46.77.15.34.03.02.41.71.7.74.15053255801051301646822132382592843093348598849099349641TheLOCAStressesarereducedby25'XperAppendixD. I.OIWCNode469SeeFigureG.3.7"GaP-OrillPlateNode954VerticalSupportNode19DrillPlate-P~rtialEggcratepartialEggcrateSatuingFullcerateFIGUREA.3ANSYSFFNITEEI,EMENTMODELA.3 Node469DrillPlate-Node959DrillPlateNode19Partia1Eggorate'sLOCAStressSSEStressFZGUREC.lLOCAHAXIHUHSTRESSLOCATIONS C.3 / .812.825.837.858.862.875.887.188.112.125FIGUREC.2TIHEHISTORYOFLOCARENDINGSTRESSNODES259,284,309,334,and359 i 613686GrillPLate338883.5833888358FIGUREC.3GEOHEXRYATHAXINUNLOCASTRESSLOCATIONC.S R%+~~~wos

3DIP.21969XX59INE.812.825.837.858.862.875.887.188.112.125FIGUREC.5TIMEHISTORYDISPLACEMENTSp NODES19,259,and469C.7 C DI1~'yJj:NE.812.825.837.858.862;875.887.188.1]12.125FIGUREC.6TIHEHISTORYDISPLACEHENTS; NODES459and959C.S

40NODE9643025tA~CAcnC920MCQNODE25915NODE959,101.0GAP(IN)FIGUREC.8PARAMETRIC EVALUATION OFBENDINGSTRESSVS,GAPWIDTH1.5 L APPENDIXD'IMPORTANT FINDINGSFROMEPRI/CEPROJECTS144Abriefdiscussion regarding theabovetestprogramispresented inthissection.Theobjectives oftheprogramare(i)toverifytheCEFLASHCodemodelingofthefluid-dynamic loadsinasteamgenerator tubeduringaLOCAand(ii)toverifythepredicted structural responses. Thetestloopsimulated theprimarysidethermal-hydraulic conditions inanoperational nuclearsteamgenerator .Theloopconsisted offivefullsizedouble90bendtubesandsteamgenerator plena,apressurizer, a0reactorresistance simulator, aheater,apump,andassociated pipesandvalvestocompletethesystem.ThetubesusedwereoftypicallengthandthesameoutsidediameterasthoseusedinCfsteamgenerators. Prototypical supportswereprovidedforthebundleoffivetubes.SeeFigureD.1whichisaphotograph oftheteststand.Coldlegguillotine breaksweresimulated usingquickopeningvalveandrupturedisks.Breakopeningtimesrangedfromlessthan1msectoasmuchas67milliseconds. Theloopinstrumentation wasdesignedtomeasurethetransient pressurehistoryatvariouslocations andmonitorthestructural responseofthetubetotheLOCAhydrodynamic loading.Aseriesofblowdowntestswereperformed fordifferent operating andboundaryconditions. Theparameter variations includedfluidtemperature, pre-blowdown flowrate,breakopeningtime,breakopeningarea,andbreaklocation. Bothuniformandmixedlengthtubebundleswereused.Analytically predicted transient pressurehistories andthedifferential pressurehistoryacrossthetubespanwerecomparedwiththeexperimental data.SeeFigureG.2.Predicted structural responses inthebendregionwerealsocomparedwiththetestdata.Thetransient pressurehistories aspredicted byCEFLASMwereinexcellent agreement withthetestdata.Thecalculated structural 'responses ofthetubealsohadgoodoverallagreement withthetestdata.0.0

Duringthecourseofthetestprogram,mechanical testswereconducted tomeasurethestructural dampingofthehorizontal tubespan.Itwasfoundtobe8Xofthecriticaldamping.Itwasalsoobservedthatthefrictional and"binding" forcesintheverticalsupportreducedthepredicted bendingstressesanaverage34.3X.SeeTableD,l.AsshowninTableD.1,theanalytically predicted bendingstressesinthisreportwerelowered25.1X(34.3X-1standarddeviation 9.2X=25.1%)totakeaccountofthefrictionandbinding. 44,~j~Pr,~I4((/~~~~~~~i~~FIGURE0,1EPRI/CEPROGRNIS144-1LOCABLOLJDONN SIMULATION TESTSTAND0.2 ~I~Ett.A5ltCXPKRIMEHSAI. ~!CSiCC:SC.C.S.CIA~VASS.CI~ISO~0C>FOROSV'-tttIKlN5KC00IIIIIII'ACCELERATjON A001CtOitI~9aoCH~IOINIISs0Ctl.tart<iO,ttvSSC, IjIIII~BaselineMeasuredandPredicted PressureDifferentials BetweenTubeBendsIZ000O.OOO.OV0.00O.CO0.IO0.IZ0.IV0.IOtt~ISCC.IAcceleration atTubeMidspanTestA34I5IOSTRESSSGQQCIIiIOwltSICSICg.tRtingv0SC.35v555IOl5Nlbwgret~CIIUSILM0.0.00O.OV0.000.00O.IOC.llO.IVO.ISll+ISSC.IBendingStressesinTubeNearSupportPlate-TestA34FIGURE0.2COMPARISON BETWEENPREOICTEO ANDMEASUREDFLUIDDYNAMICLOADINGANDSTRUCTURAL RESPONSE-0.3 TABLED.tPALISADES STEAMGENERATOR 1.0CAANALYSISBATWINCiFRICTION-EPRITESTEPRITESTANSYSANALTestIDDescription BreakOpenT(Sec)Reports(ksi)Corrects(ksi)WithFPs(ksi)ReportNoFPs(ksi)XDueFrictA-28SmallerBreakArea(Downstream Orifice).0175.55.710.712.246.7A-31A-37A-37ShortBreakLengthMixedHeightBundle(L'ongTube)MixedlleightBundle(ShortTube).016.014.0146.45.810.36.66.010.79.89.014.211.210.316.332~733.324.6AverageValueStandardDeviation SelectedValue(Avg-S)34.39.225.1 C APPENDIXEEVALUATION OFNRCSTAFFCRITERIAARTICLEE.lPROCEDURE FORDETERMINING ALLOWABLE,TWD TABLEE.lRELATEDDATAFORALLOWABLE TWDDETERMINATION FIGUREE.lEVALUATION PERNRCREG.GUIDE1.121FIGUREE~2ALLOWABLE TUBEWALLDEGRADATION BASEDONLOCA+SSESTRESSESFORTUBEROWS117-123FIGUREE.3ALLOWABLE TUBEWALLDEGRADATION FORTOTALTUBEBNUNDLEFIGUREE.4MEMBRANEANDBENDINGINTERACTION DIAGRAMFORCYLINDRICAL TUBEE,O C ARTICLEE.1PROCEDURE FORDETERMINING ALLOMABLE TMDLOCA+SSEThemaximumallowable stressintensity foradegradedtubeforLOCA+SSEstressisdetermined fromthefollowing equation: S.I.22.21/2LOCASSELOCAXA+a-e=f(0.7)SuRAREIMPi.'XP'rP=(Equation E.l)TheLOCArarefaction, impulse,andsafeshutdownearthquake stressesareevaluated bytheSRSSprocedure forahealthytubeandthenamplified bythefactorA.whichistheratioofthesectionmodulusofadegradedtubetoahealthyone.Tubestressesduetoadeltapressure, primaryminussecondary, areincludedandcomparedtoanallowable, f(0.7S)wherefisuafunctionofcross-sectional geometryandtheratioofmembraneandbend-ingstressestoyieldstress.Aninteraction graphisshowninFigureE.4.Thiswasdeveloped foracylindrical tubecross-section formembraneandbendingstresses. TableE.lpresentsdatacalculated foruseintheaboveequationforS.I.ThethreemodelrowswithmaximumLOCArarefaction stressesarell,12,and13corresponding tosteamgenerator tuberows117-118,119-121and122-124,respectively. ThesevaluesareshowninTableC.l.ModelRow11Evaluation: (UseTMD59%Input)S.I.=[(28.3)+(7.1)+(4)](2.559)+4.3+.82 =80.5<Allow.=80.6ksi ModelRow12Evaluation: (UseTWD62%Input)S.I.=[(26)+(5.3)+(4))(2.776)+4.7+.82 =79.9<Allow.=80.6ksi2221/2ModelRow13Evaluation: (UseTWD68%Input)S.I.=[(21.5)+(4)+(4)](3.305)+5.2+.82 =79.6<Allow.=80.6ksiFiguresE:2andE.3showtheallowable TWDforthelocalized regionandtheentiretubebundle.NSLB+SSEAllowable TWDisdetermined normallybyconsidering stressesfromfoursources.1)MSLBflowloads,2)MSLBimpulseloads,3)Safeshutdownearthquake and4)differential pressure. Stressesresulting from1),3),and4)havebeendetermined. NSLBimpulserelatedmaximumstressisas-sumedtobe+6ksi,basedonananalysisofasteamgenerator ofsimilardesign,andisusedinthisportionoftheevaluation. ItshouldbenotedthatNSLBimpulserelatedstressesaregenerally smallerthanMSLBflowstressesandwiththecombining ofstressesutilizing theSRSSprocedure, theeffectofMSLBimpulsestressesontheresultant valueisfurtherde-creased.TheworstcaseNSLB+SSEstressesaretakenfromSectionVIIIandusedtoevaluatetheallowable TWD.NSLBFlowStress=9.77ksiSSEStress7.6ksiMSLBImpulseStress=6.0ksiResultant =(9.77+7.6+6.0)=13.7ksiE.2

Solvingequation. E.lusinganallowable TWOestimateof66percent,thestressintensity, S.I.forMSLB+SSEis65.3ksi.Theallowable S.I.isf(.7)S=66ksibasedonavalueoff=1.18ob-utainedfromFigureE.4.TheratioofmembranestresstoyieldforInconeltubingis0.81asshownbelowandisrequiredtodetermine f.a=-='22.6ksii2.25.327m2tr=0.81.'.f=1.18fromFigureE.4m22.6Hence,themaximumallowable TWDforMSLB+SSEstressesis66percentwhichisnon-controlling. E.3 TABLEE.lRELATEDDATAFORALLOWABLE TWDDETERMINATION TWD585960616266686970t(IN).0201.0197.0192.0187.0182.0178.0163.0154.0149.0144R(IN).3471.3467.3462.3457.3452.3448.3433.3424.3419.3414ZDIN.006972.006828.006649.006471.006293.006151.005618.005286.005124.004948HIN.017470.017470.017470.017470.017470.017470.017470.017470.017470.017470A.ZH/ZD2.5062.5592.6272.7002.7762.8403.1103.3053.4093.531xP(KSI)4.34.34.44.64.74.85.25.65.75.84PRixP~trP>=1336psiP2=815psiWherehP=Pq-P2=0.521ksicr=0.815ksi((rremb)=g7g=0.18..f=1.44(FigureE.4)5SSE=2.2ksi(HealthyTubeatTimeandLocationofMaximumLOCAStress)0LOCA40ksi(HealthyTube)IMPE.4 4 1.NORMALOPERATION 2.NORMALOPERATION 3.STEAMLINEBREAKa<S=27.9KSI,600F3a<S=80.0KSI,600Fa<.7S=56.0ksi,600FNORNLOPERATING PRESSURES rS-.P+P36PR'S+U~PRi07S-.P+PP>=2250psiaPz=815psiahP=1435psiSTEANLINEBREAKPg=0Pi=2250psia1.435.3273.65t=0.0178in.XAllow.Degradation (.048-.0178)X100.0483(1.435.327r8tr=0.0179in,XAllow.Degradation 0100.048-,0179=632.25.327rtr=0.0134in.XAllow.Degradation 0100='72FIGUREE.1EVALUATION PERNRCREG.GUIDE1.121 CI I,!eIII'I1aIaa70III~a;aI..I{e~IIaa,I.I{,IIe~~~~I~\IaalII~I~II~~I~aIaIjr~I~eIaI~tI~I{.LOCA+SSE~I~I*~I':{~EIVALUAl'ION 1j,I'il~."'IIj'"~IelII~IaIIIIIl~-~IIIj"IIIIIIII~~II~Ia-'--".66.MlC)~ic)6258IaI.I-i".I{I'IjI..~NRC']a~I.IIIIII,j~ACCEPTABLE REGIONSTAFF{leI-~4~-~Ia~~aROWi..NUMBER!I>>7.>>8>>9120'aiI~'{ICRITERIA',',I..I..j{'UBES PERROW46454443.V~a~I~IaIIII-Q5'6IIIALLOWABLE TUBEIa1III140Ia'E'ROWS>>73123 ~"'EI~II1t7';-118,;j{ 119,120:121122:123aTUBEROMNUMBERII'r'IIli~I',.'FIGUREE.2.lI"WALLDEGRADATION BASEDON'LOCA+SSE ST!{ESSES.FOR TUBt-eIIIaI~ el II,~jI~IIIIII',-801,',70-60'~rIIjIr~-II,II~Ii~IiII,iII)~'IIiIHRCSTAFFCRITERIA~~l'i'~"~~IIItrt".rIr'rIlj~II,i1~II~..LOCA+SSE;EVALUATION h:/Ii-~1ICDI-C)CYC9C)IJJCOCDcC.50=4030I-'.2010I~IIIACCEPTABLE REGIONit.'I.II~!.III!IItIr.)I00~20.";-40ljrIi..=1'~IIl'I~~"ALLOWABLETUBE WALLi,FIGUREE.'3I-DEGRADATION FORTOTjALTUBPBUNDLE'IIII6080'100ITUBEROMNUMBER120II~Irl~IiI140I r cP"M5-"CAVl,UJs~CY-li4UJCAUJCLI-1.3COC)LVCXl'-'4--:l2.~t~~~~s~~I,.(~63KDEGRADEDTUBE'IIHEALTHYTUBE~1~."'-..-.:-.j 'I":00.20.40.60.81.0MEMBRANE"MEMBRANESTRESS/YIELD STRESSFIGUREE,4ANDBENDINGINTERACTION DIAGRAMFORCYLINDRICAL TUBEI~>~~~IE.8

APPENDIXFFATIGUEANALYSISOFDEGRADEDTUBESThefatigueevaluation ofadegradedtubeisbasedupontheconservative assumption of15,000cyclesfromambientconditions to1005power.Theresulting alternating stressintensity is(Ref.16,PageA-465)Slt=16.8ksiAstressconcentration factorforatubethatisdegraded63$isdetermined byconsidering astriponthetensionsideofthetubeandtreatingitasashouldered plateintension.(Ref.17,Page178).DegradedZoneTransition AreaAfullfilletradiusisassumed0.018"pdTR=.03h=.03d=.036D=.096d=D/dh0.65~h-Y0~6s=1.33Applying. thisstressconcentration factoryieldsSalt=(1.33)(16.8 )=22.4ksi.Thisalternating stressisgoodforcyclesinexcessof106(seeFigureI-9.2,Reference 2).f/ence,theusagefactorisE.O 4r' ATTACHMENT EDETERMINATION OFNOSIGNIFICANT HAZARDSCONSIDERATION Thestandards usedtoarriveatadetermination thatarequestforamendment involvesnosignificant hazardsconsideration areincludedintheCommission's regulations, 10CFR50.92,whichstatesthatnosignificant hazardsconsiderations areinvolvediftheoperation ofthefacilityinaccordance withtheproposedamendment wouldnot(I)involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated; or(2)createthepossiblity ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated or(3)involveasignificant reduction inamarginofsafety.Eachstandardisdiscussed asfollows:(I)Operation ofthefacilityinaccordance withtheproposedamendment wouldnotinvolveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated. Theproposedsteamgenerator tubewallacceptance criteriahasbeendetermined inaccordance withRegulatory Guidel.l2I.Theacceptance criteriaisbasedonmarginsofsafetyconsistent withthemarginsprovidedinSectionIIIoftheASMEBoilerandPressureVesselCode.Thedemonstrated marginsofsafetyprovidereasonable assurance thattubefailurewillnotoccurduringoperating oraccidentconditions. Therefore, theproposedchangewillnotresultinasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated. (2)Useofthemodifiedspecification wouldnotcreatethepossibility ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated. Theproposedchangedoesnotchangetheconfiguration oftheplantorthewayinwhichitisoperated. Therefore, thechangedoesnotcreatethepossibility foranewordifferent kindofaccidentfromanypreviously evaluated. (3)'Useofthemodifiedspecification wouldnotinvolveasignificant reduction inamarginofsafety.Thesupporting steamgenerator tubestressanalysismeetsthecriteriaofRegulator'y GuideI.I2I.Theproposedacceptance criteriaisbasedonsafetyfactorsof3fornormaloperating conditions andI.Sforaccidentconditions. Theassociated marginsofsafetyareequivalent tothemarginsdetermined bythestresslimitsofSectionIIIoftheASMEBoilerandPressureVesselCode.Thesemarginsofsafetyassurealowprobability fortubefailureduringoperating oraccidentconditions. Therefore, theproposedchangedoesnotresultinasignificant reduction inamarginofsafety.Basedontheabove,wehavedetermined thattheamendment requestdoesnot(I)involveasignificant increaseintheprobability orconsequences ofanaccidentpreviously evaluated, (2)createtheprobability ofanewordifferent kindofaccidentfromanyaccidentpreviously evaluated, or(3)involveasignificant reduction inamarginofsafety;andtherefore doesnotinvolveasignificant hazardsconsideration. EJW2/024/5 Vcrl~hvhv+f>>urv( ~vv1-~l~4~I,cr'wr44$ JI>>riv4>>54th'-4vr'4>>r ril,~4ItI>>WW.l4Ili~41I4IvI"~..4vc,l,".>>A4"444Ii~i>>8441~*~4vlt.4~i'l,IIIJ"Ill')MIHltil'.1hvtI11'-/[IIII,4~h1~4bil~'uvlt"II4*Vi,Vuhc"IlhI1v1"II~>>"I,llti44h4t'Jkvlt-lt'hclv*"'1>>llIII4'I'.WII>>vI,4'fv'W~~~t4P,4ItI~I44-II,~4...I,'ll,44ILWIlh>>MI14il4.I,IIIJlIih'llIVWI'>>I'I,,4,IqlI-'I',h."A').;IHl14.,44lttvvc4JW1lrV'WCIVhcl1JVC44~li'h.,I~i'1'1IvhI1til.H<'Itf"i<,.ll'~viIIIIllih~4*~,ukill4Ill;4~1-J'ilHWW(flicI~4444t:~~,ihv,'I>>v".$ttgvuhhiff4IiH'lilhivlhhilvWW41It14~.Ii.~IvHw4I'tvr\IiHCH"I'IiilWI4atilwli,4vvuIHAut,c.>>44~44JIIJ44W4".~4Irc,>>4ilHl,III4I'IllI1VW.~I,j'4*14A~.IIHtlijl'1hl,WtjVC',rI>>441441IIlt4,It~(11>>J44,Illl-4"ICInJl.~1I.I444~4li44hitIhi'I4~I'.~il4}}