ML17261A877
| ML17261A877 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 03/06/1989 |
| From: | MECREDY R C ROCHESTER GAS & ELECTRIC CORP. |
| To: | STAHLE C NRC |
| References | |
| IEB-88-011, IEB-88-11, NUDOCS 8903150532 | |
| Download: ML17261A877 (5) | |
Text
,gccE~~TEDD1.'>1;jEIUTIONDEMONSTR~TeINSYSTEMREGULATORYINFORMATIONDISTRIBUTIONSYSTEM(RIDS)ACCESSIONNBR:8903150532DOC.DATE:89/03/06NOTARIZED-YESDOCKETgFACIL'.50-244RobertEmmetGinnaNuclearPlant,Unit1,RochesterG05000244AUTH.NAMEAUTHORAFFILIATIONMECREDY,R.C.RochesterGas&ElectricCorp.RECIP.NAMERECIPIENTAFFILIATIONSTAHLE,C.NRC-NoDetailedAffiliationGiven
SUBJECT:
Discussesobjectivesofutilprogramtoconfirmpressurizersurgelineintegrity,perNRCBulletin88-011.DISTRIBUTIONCODE:IE11DCOPIESRECEIVED:LTRENCLSIZE:TITLE:BulletinResponse(50DKT)NOTES:LicenseExpdateinaccordancewith10CFR2,2.109(9/19/72).05000244RECIPIENTIDCODE/NAMEPD1-3LASTAHLE,CINTERNAL:AEOD/DOANRR/DEST/ADE8HNRR/DEST/MEB9HNRR/DOEA/GCB11QJGkSQDLRB12GN1ILE01EXTERNAL:LPDRNSICCOPIESLTTRENCL1011111111111111111111RECIPIENTIDCODE/NAMEPD1-3PDAEOD/DSP/TPABNRR/DEST/ADS7ENRR/DOEA/EAB11NRR/DREP/EPB10NUDOCS-ABSTRACTRES/DSIR/EIBNRCPDRCOPIESLTTRENCL111111111111111'.1NOTE'IOALL"RIDS"RECIPZEÃIS:PLEASEHELPUSTOREDUCEWASTE!CONTACT'IHEDOCUMEMI'GÃIBOLDESK,RXMPl-37(EXT.20079)IOELQ~TEARKNAMEFRYDISTEKBVZIGNLISTSFORDOCt2KMISYOUDGN~TNEEDfTOTALNUMBEROFCOPIESREQUIRED:LTTR19ENCL18 March6,1989U.S.NuclearRegulatoryCommissionDocumentControlDeskAttn:Mr.CarlStahlePWRProjectDirectorateNo.1Washington,D.C.20555
Subject:
NRCBulletinNo.88-11AlternateScheduleforEvaluationofPressurizerSurgeLineThermalStratificationR.E.GinnaNuclearPowerPlantDocketNo.50-244
DearMr.Stahle:
OnDecember20,1988,theNRCissuedBulletinNo.88-11"PressurizerSurgeLineThermalStratification".Itrequestsalladdresseestoestablishandimplementaprogramtoconfirmpressurizersurgelineintegrityinviewoftheoccurrenceofthermalstratification,andrequiresthemtoinformthestaffoftheactionstakentoresolvethisissue.PursuanttosatisfyingtherequirementsandschedulesofBulletin88-11,RochesterGasandElectricCorporationisparticipatinginaprogramforpartialresolutionofthisissuethroughtheWestinghouseOwner'sGroup(WOG).TheWOGprogramwasapprovedattheOctober1988meetingandhasthefollowingobjectives:~DevelopagenericJustificationforContinuedOperation(JCO)toassurethatplantsafetyisnotcompromisedwhiletheeffectsofthermalstratificationarebeingdetermined.Collectandsummarizerelevantdesign,operational,analytical,andtestdataforasmanyWOGplantsaspossible.Inaddition,arepresentativesampling,ofapproximatelytenplants,willbeselectedtoperformareviewofplantrecordsandconductinterviewswithoperationspersonnel.~Evaluatedataandidentifyandprioritizesignificantparameterscontributingtothisissue.Categorize(group)~~plplantsbasedontheseparameters.w'0~~'203i5053239030'~PDFAGOCK0.":000244
~RecommendadditionalmonitoringtosupplementtheexistingtransientdatabaserequiredtoboundallWOGplants.Estimatetheeffectofthermalstratificationonfatiguelifeasafunctionofkeyparameters.~Recommendshorttermandlongtermactions.TheWOGprogramisdesignedtobenefitfromtheexperiencegainedintheperformanceofseveralplant.-specificanalysesonWestinghousePWRsurgelines.Thesedetailedanalysesincludeddefinitionofrevisedthermaltransients(includingstratification)andevaluationsofpipestress,fatigueusagefactor,thermalstriping,fatiguecrackgrowth,leak-before-break,andsupportloads.Theoverallanalyticalapproachusedinalloftheseanalyseshasbeenconsistentandhasbeenreviewed,indetail,bytheNRCstaff.Asignificantamountofsurgelinethermalmonitoringdatahasbeenobtainedinsupportoftheseplant-specificanalyses.AdditionalsurgelinethermalmonitoringandplantsystemdatacontinuestobemadeavailablewithintheWOG,resultinginasteadilyincreasingdatabase.Asignificantamountofprogresshasbeenaccomplishedtowardmeetingtheseobjectives.Todate,theWOGhascompletedapproximately80-odftheeffortofassemblingplant-specificdesigninformationonalldomesticWestinghousePWRs(55unitstotal);Theeffortwillestablishtherangeofkeydesignparametersandpermitgroupingofplantsbasedontheseparameters.Basedontheinformationassembledtodate,andtheexperiencegainedinplant-specificanalysesandmonitoringprograms,theWOGevaluationhasresultedinthefollowingobservationsregardingplantsimilarityandthermalstratification:1.Thermalstratification(>100'F)hasbeenmeasuredonallsurgelinesforwhichmonitoringhasbeenperformedandwhichhavebeenreviewedbytheWOGtodate(7plants).2.Theamountofstratificationmeasuredanditsvariationwithtime(cycling)varies.Thisvariationhasbeenconservativelyenvelopedandapplicabilitydemonstratedforplant-specificanalyses.AdditionalmonitoringdatarepresentingawiderrangeofsurgelineconfigurationsmaybeneededinordertodemonstratetheapplicabilityofthesethermalstratificationtransientstootherWestinghouseunits.3.Significantfactorswhichcaninfluencethestructuraleffectsofstratificationare:a.Locationanddesignofrigidsupportsand.restraintsb.Pipelayoutgeometryandsizec.Typeandlocationofpipingcomponents 4.AlthoughthematerialandfabricationtechniquesforWestinghousesurgelinesarereasonablyconsistentandofhighquality,thedesignparameterslistedinitem3varyamongWestinghousePWRs.Thisvariationindesignisprimarilyaresultofplant-specificroutingrequirements.Thisvariabilityiscurrentlybeingexaminedinordertoasse'ssthefeasibilityofa.boundinganalysisapproach.TheseobservationsdevelopedthroughtheongoingWOGprogram,indicatethatthedevelopmentofthermalstratificationloadingsandtheevaluationoffatigue,consideringtheseloadings,isacomplexprocess.Therefore,inordertopreciselyevaluatestratification,additionaltimeisneeded.Whilemoretimeisneededtoevaluatethestratificationissueindetail,theNDEinspectionhistoryatR.E.Ginna,aswellasallotherdomesticWestinghousedesignedPWRs,hasnotrevealedanyserviceinduceddegradationinthesurgelinepipingthathasbeenattributedtothermalstratification.Inaddition,alltheplant-specificanalysesperformedtodatethathaveincludedtheloadingsduetostratificationandstripinghavevalidatedthe"leak-before-break"conceptandhavesubstantiateda40-yearplantlife.Thus,aprudentapproachforprovidingadetailedevaluationoftheeffectsofsurgelinestratificationwouldbetofollowtheWOGprogramgroupingevaluationrecommendationsandmonitorasdeterminedtobeappropriate.TheWOGhascompletedagroupingevaluation,forthepurposeofrecommendingalistofadditionalplantswherethermalmonitoringisneeded.Thetimerequiredforthisadditionalmonitoringwillbedependentonplantoutageschedules.Toassurethattheplantsafetyisnotcompromisedwithintherequestedperiodofscheduleextension,aJCOwillbeprepared.TheJCO,whichiscurrentlybeingdeveloped,willbeavailableforstaffreview,ifdesired,within4monthsofreceiptoftheBulletin.TheJCOwillutilizetheinformation,experience,andmonitoringdataobtainedthroughtheWOGprogram,andwillsupportthealternateschedulediscussedherein.RochesterGasandElectricCorporationherebyrequestsanalternatescheduletothatrequestedinBulletin88-11.Ascheduleoftwoyears,fromreceiptoftheBulletin,isconsideredsufficienttimetoobtainthenecessaryadditionalmonitoringdata,definethermaltransients,performallrequiredanalysesandupdatethestressandfatigueanalysestoensurecompliancewithapplicablecodeandregulatoryrequirements.Thisschedule,thoughdifferentfromthatrequestedinaction1.bofBulletin88-11,isconsistentwiththerequirementtoupdatethestressandfatigueanalyseswithintwoyearsasstatedinaction1.do~eBulletin.
Atthistime,RochesterGasandElectricCorporation'srequestforanalternatescheduleappliesonlytoitem1.bofNRCBulletin88-11.RochesterGasandElectricCorporationintendstocomplywithallotherrequirementsoftheBulletin,butwillinformthestaffandjustifydifferences,ifappropriate.Verytrulyyours,RobertC.MecedyGeneralManagerNuclearProductionRWEN024Subscribedandsworntobef'oremeonthis6thdayofMarch,1989.JAMESC.McGUiAENTARYPUSUC,StateoiNewYorkOuaIfiedinhbnroeCourttyMgCoinnissionExp@aOec.28,t9'zc:U.S.NuclearRegulatoryCommissionRegionI475AllendaleRoadKingof'Prussia,PA19406GinnaSeniorResidentInspector