ML18040A167

NMP Nine Mile Point Unit 1 Nuclear Power Station Rept of RPV FW & CRD Return Line Nozzle Exams Performed for NUREG-0619...at Culmination of Refueling Outage 13 Which Ended on 950404.

ML18040A167
Person / Time
Site:	Nine Mile Point
Issue date:	09/29/1995
From:	NIAGARA MOHAWK POWER CORP.
To:
Shared Package
ML18040A166	List: ML18040A165 ML18040A167
References
RTR-NUREG-0619, RTR-NUREG-619 NUDOCS 9510100318
Download: ML18040A167 (42)

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NIAGARAMOHAWKPOWERCORPORATIONNINEMILEPOINTUNIT1NUCLEARPOWERSTATIONREPORTOFREACTORPRESSUREVESSELFEEDWATERANDCONTROLRODDMVERETURNLINENOZZLEEXAMINATIONSperformedforNUREG0619BWRFEEDWATERNOZZLEANDCONTROLRODDRIVERETURNLINENOZZLECRACKINGattheculminationofREFUELINGOUTAGENO.13whichendedonApril4,1995ThisdocumentcompletedSEPTEMBER29,19959510100318951003PDRADOCK05000220,,P...,PDR,,

l~Q NMP1RPVFEEDWATERANDCRDRLNOZZLEEXAMINATIONS1995REFUELINGOUTAGE(RFO-13)TABLEFCNTENTSINTRODUCTION...................................1ACKGROUND....................................1BRESULTSOFEXAMINATIONS.........................2MODIFICATIONSANDSYSTEMCHANGES................2STARTUP/SHUTDOWNCYCLES........................3LEAKAGEMONITORING.............................3VlaARYe~~~~~~~~~~~~~~~~~'o~~~~~~~~~~~~~~~~~~~~3SEFERENCESe~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~o~~~~~5RAPPENDICESA.FEEDWATERANDCONTROLRODDRIVERETURN.....7LINENOZZLEINSPECTIONRESULTSB.MODIFICATIONSORSYSTEMCHANGESTHAT.......15AFFECTFEEDWATERFLOWORTEMPERATUI&C.ULTRASONICEXAMINATIONTECHNIQUES..........16

~'NMP1RPVFEEDWATERANDCRDRLNOZZLEEXAMINATIONS1995REFUELINGOUTAGE(RFO-13)I.INTRODUCTIONThisreportprovidestheinformationrequiredbyNUREG-0619,"BWRFeedwaterNozzleandControlRodDriveReturnLineNozzleCracking"(November1980).Thereportincludes:Asummaryofmethodsused,theresultsoftheinserviceinspectionsofthefeedwaterandcontrolroddrivereturnline(CRDRL)nozzlesandfeedwaterspargerflowholesandweldsinspargerarmsandtees,theeffectsofmodificationsorsystemchangesonfeedwaterflowortemperature,thenumberofstartup/shutdowncycles,andadiscussionofthermalsleeveleakagemonitoring.TheinspectionswereperformedbytheGeneralElectricNuclearEnergyCorporation(GE-NE)ofSanJose,California.H.BACKGROUNDNineMilePointUnit1isa620MweBoilingWaterReactor(BWR)whichbeganoperationinNovember1969andhasbeeninserviceforapproximately26years.Duringthe1977RefuelingOutage,NiagaraMohawk(NMPC)removedtheoriginally-installedloose-fitfeedwaterspargersandreplacedthemwithanimproveddesign(single-pistonring/flowbaffleseal).Thefourfeedwaternozzleswereultrasonically(UT)examinedfromthereactorvesselexteriorusingproceduresandtechniquesdevelopedbyGeneralElectric(GE).ThisUTexaminationestablishedabaselineforsubsequentnozzleexaminations.AsrequiredbyNUREG-0312,"InterimTechnicalReportonBWRFeedwaterNozzleandControlRodDriveReturnLineNozzleCracking,"aninserviceUTanddyepenetrant(PT)examinationofthefourfeedwaternozzleswasperformedbyGEduringthe1979refuelingoutage.Nosignificantchangesfromthebaselineexaminationswereobserved.Inaddition,theReactorWaterCleanup(RWCU)returnlinewasreroutedtothefeedwaterlines.InNiagaraMohawk'sresponsetoNUREG-0619,datedDecember29,1980,wecommittedtoaprogramofperiodicinspectionsofthefeedwaterandcontrolroddrivereturnlinenozzles.ThefeedwaternozzleUTinspectionwastobeperformedeveryotherrefuelingoutageandthevisualinspection(VT)ofthefeedwaterspargerswastobeperformedeveryfourthrefuelingoutage,commencingwiththe1981outage.ThePTinspectionofthefeedwaterandcontrolroddrivereturnlinenozzleswastobeperformedeverysixthrefuelingoutageorevery90startup/shutdowncycles,whicheveroccurredfirst.ThePTInspectionintervalscommencedwiththe1979refuelingoutage,duringwhichthebaselinefeedwaternozzlePTinspectionsweremade.

I NMP1RPVFEEDWATERANDCRDRLNOZZLEEXA1VHNATIONS1995REFUELINGOUTAGE(RFO-13)H.BACKROUNDCont'dDuringthe1988RefuelingOutage(RFO-11),theNMPCNuclearQualityAssuranceDepartmentgeneratedCorrectiveActionRequest88.2039-01todocumentandresolvediscrepanciesinpreviousoutages'eedwaternozzleexaminationdata.Alsogeneratedduringthe1988outagewastheRestartActionPlan(RAP).OneoftheRAPspecificissuesaddressedthelackoffullvolumecoverageonfeedwaternozzlesasrequiredbyNUREG-0619.Allofthecorrectiveactionsforbothoftheseissueswereidentifiedandimplementedduringthe1988outage.The1988UTexaminationsofthefeedwaternozzlesperformedbytheNuclearEnergyServicesCo.(NES)revealedindicationsthatwouldrequiremonitoringduringthefollowingrefuelingoutage.TheUTexaminationsconductedduringRFO-12in1993offeedwaternozzle"A"wereperformedbyGeneralElectricNuclearEnergy(GE-NE).TheresultsoftheseexaminationswerepresentedinNMPC'ssubmittalofAugust25,1993(NMP1L0777)whichindicatednorecordableindicationsandresolvedthoseindicationsidentifiedin1988duringRFO-11asrequiringadditionalmonitoring.Visualexaminations(VT)ofthefeedwaterspargerflowholesandweldsinspargerarmsandteeswereperformedbyGE-NEduringRFO-11in1988andagainduringRFO-12in1993,Theseexaminationsindicatednoreportableindications.III.RULTSOFEXAMINATINTheinspectionsconductedduringRFO-13in1995wereperformedwiththeUltrasonicTest(UT)methodbyGE-NEwhichindicatednoreportableindications.TheseUTexaminationsutilizedtheGERIS2000automatedsystemandmanualUTpickupsoftheRPVnozzlesonfour(4)feedwaterandthecontrolroddrivereturnlinenozzles.TheresultsoftheseexaminationsandasummaryofallpreviousexaminationsarepresentedinAppendixAofthisreport.IV.MODIFICATIONSNUREG-0619requireslicenseestoreportallmodificationsorsystemchangesthataffectfeedwaterflowortemperatureandtoconsiderthesechangesinpredictingfuturecrackingtendencies.Sinceour1988outageNUREG-0019report,therehavebeennomodificationsorsystemchangesthataffectfeedwaterflowortemperature.AppendixBtothisreportsummarizesallapplicablephysicalandproceduralmodificationsimplementedatNineMilePointUnit1since1977whichaffectfeedwaterflowortemperature.

NMPIRPVFEEDWATERANDCRDRLNOZZLEEXAMINATIONS1995REFUELINGOUTAGE(RFO-13)V.TARTUP/HUTDWNCYCLThefeedwaterandcontrolroddrivereturnlinenozzleshaveexperienced171startup/shutdowncyclessinceinitialplantoperation.Thecontrolroddrivereturnlinenozzlehasexperiencedonly63startup/shutdowncyclessincethePTexaminationin1979.Table1providesfurtherdataonthenumberofstartup/shutdowncyclesfromoutagetooutagesince1977.VI.LEAKAGEMNITRINGNiagaraMohawkhasnotinstalledanon-linebypassleakagemonitoringsystematNineMilePointUnit1(NMP1).Thethermalsleevedesignincludesflowbafflesthatpreventmixingofthehotreactorwaterandthecolderfeedwaterinthenozzleannulus.NUREG-0619,Section4.3.2.4specificallyexemptsNMP1fromthisrequirement.VII.8UMMARYThenondestructiveexaminationsperformedduringthe1995RefuelingOutage,tu'0-13,identifiednoreportableindicationsthatwillrequiremonitoringinaccordancewithNUREG-0619.NMPCanticipatestocontinueutilizinganautomatedinspectionmethodsuchastheGEGERIS2000automatedsystemforfutureoutagesasdescribedinNMPC'ssubmittalofJune23,1994(NMP1L0829).

I NMP1RPVFEEDWATERANDCRDRLNOZZLEEXAMINATIONS1995REFUELINGOUTAGE(RFO-13)TABLEINUMBEROFSTARTUPHUTDWNCYCLATNINEMILEINTT1PERIODNUMBEROFCYCLESDURINGPERIODCUMULATIVE1969InitialStartup-1977RefuelingOutage1977RefuelingOutage-1979RefuelingOutage1979RefuelingOutage-1981RefuelingOutage1981RefuelingOutage-1983Safe-EndOutage1983Safe-EndOutage-1986RefuelingOutage1986RefuelingOutage-1987FeedwaterTransientOutage(1988RefuelingOutage)1988RefuelingOutageRFO-111993RefuelingOutageRFO-121993RefuelingOutageRFO-121995RefuelingOutageRFO-13951317141795108125127141149166171

VIII.R~RPERRNCNMP1RPVFEEDWATERANDCRDRLNOZZLEEXAMINATIONS1995REFUELINGOUTAGE(RFO-13)2.BWRFeedwaterNozzleandControlRodDriveReturnLineNozzleCracking,NUREG-0619,U.S.NuclearRegulatoryCommission,November1980.NMPCLetter,D.P.DisctoR.C.Haynes,U.S.NuclearRegulatoryCommission,datedJanuary4,1982(

Subject:

InserviceInspectionsofFeedwaterNozzlesandSpargersPerformedDuringthe1981RefuelingOutage).3.4,5.6.NESLetter,T.J.KochtoT.W.Roman,datedMarch4,1983(

Subject:

February,1983FeedwaterNozzleInnerRadiusExams).NESLetter,W.R.DownstoT.W.Roman,datedJune27,1984(

Subject:

April,1984FeedwaterNozzleInnerRadiusExams).NMPCsubmittaltotheNRC,datedDecember23,1986,letternumberNMP1L0119(

Subject:

1986RFO-10FeedwaterNozzleExaminationResults).NMPCsubmittaltotheNRC,datedMarch21,1989,letternumberNMP1L0374(

Subject:

1988RFO-11FeedwaterNozzleExamResults/NMPCPlansforFutureExaminationsandEvaluationofIdentifiedIndications).7.NRCLetter,datedMay1,1989,(TACNo.72944)(

Subject:

SummaryofApril18,1989MeetingtoDiscussFeedwaterIndicationsatNMP1).8.9.10.12.NMPCsubmittaltotheNRC,datedMay5,1989,letternumberNMP1L0394(

Subject:

FeedwaterNozzleIndicationFractureMechanicsAnalysis).NRCSafetyEvaluationofUltrasonicTestIndicationsintheFeedwaterInletNozzle"A"NearaNozzleSafeEnd(TAC72944),dated9/26/89.NMPCsubmittaltotheNRC,datedJanuary11,1991,letternumberNMP1L0560(

Subject:

1988RFO-11FeedwaterNozzleExaminationResults).NMPCInternalCorrespondencetoUnit1LicensingFilefromN,A,Spagnoletti,datedMarch1,1993,FileCode003631GG(

Subject:

NotesofTeleconwithNRCRegardingFeedwaterNozzle"A"UTInspection).NMPCsubmittaltotheNRC,datedAugust25,1993,letternumberNMP1L0777(

Subject:

1993RFO-12FeedwaterNozzle"A"ExaminationResults).

I NMP1RPVFEEDWATERANDCRDRLNOZZLEEXAMINATIONS1995REFUELINGOUTAGE(RFO-13)VIH.REFERENCCont'd13.NMPCNuclearEngineeringReportNo.NER-IM-006"NineMilePointUnit1FeedwaterNozzleFatigueEvaluation,"datedMay1994,(ReferenceMPR-1484,Revision0).14.NMPCNuclearEngineeringReportNo.NER-IM-007"NineMilePointUnit1ControlRodDriveReturnNozzleFatigueEvaluation,"datedMay1994,(ReferenceMPR-1485,Revision0).15.NMPCsubmittaltotheNRC,datedJune23,1994,letternumberNMP1L0829(

Subject:

AmendNUREG0619CommitmentfromPTtoAutomatedUTInspection).16.NRCLetter,datedJanuary12,1995,(TACNo.M89792)(

Subject:

AmendNMPC'sNMP1NUREG0619CommitmentutilizingtheGERIS2000SystemfromAutomatedUTInspection).

IX.APPENDICESAPPENDIXAFEEDWATERNZZLEINSPECTIONRULTAsstatedinNiagaraMohawk'sletterofDecember29,1980,theNineMilePointUnit1Feedwaterandcontrolroddrivereturnlinenozzleswillbeperiodicallyreinspectedatthefollowingintervals:~FeedwaterNozzleUT-everyotherrefuelingoutage,commencingwiththe1981outage.~FeedwaterNozzleVT-everyfourthrefuelingoutage,commencingwiththe1981outage.~FeedwaterandCRDNozzlePT-everysixthrefuelingoutageorevery90startup/shutdowncycles,commencingwiththe1979refueling.Duringthe1981refuelingoutage(RFO-8),aninserviceUTexaminationofthefourfeedwaternozzleswasperformedbyNESandalsobyGE.Anapparentchangefromthebaselineexaminationwasobserved.Furtherevaluationrequiredremovalofthespargerfromthesoutheastnozzle.Basedontheresultsoftheadditionalnondestructiveexaminations,NiagaraMohawkconcludedthattheUTindicationwascausedbyageometricreflectorandnotbyacrackinthenozzle.Anewfeedwaterspargerwasinstalledinthesoutheastnozzle.Thedesignofthenewspargerwasthesameasthereplacementspargersinstalledduringthe1977refuelingoutage.Duringthe1983safe-endoutage,inserviceinspectionsofthefeedwaternozzleswerenotrequiredbyNUREG-0619schedulecommitment.However,thenozzleswereexaminedbyNESforinformationonly.Anincreaseintheamplitudeofthesignalfromthegeometricreflectorinthesoutheastnozzlewasnoted.Amorerigorousevaluationofthisindicationwasperformedduringthe1984refuelingoutageclearlyidentifyinganddocumentingthatthisreflectorisgeometricandhasexhibitednogrowthorchange.Duringthe1986refuelingoutage(RFO-10),inserviceUTexaminationsofthefourfeedwaternozzleswereperformedbyNES.Nosignificantchangesfromthepreviousexaminationswereidentified.Duringthe1988refuelingoutage(RFO-11),inserviceUTexaminationsofthefourfeedwaternozzleswereperformedbyNES.Theseexaminationsidentifiedapproximately25indicationsinthevicinityofthenozzletosafe-endweldofthenortheastnozzle"A"at45degrees.Althoughtheseindicationsmighthavebeencausedbyscratchmarksmadeduringspargerinstallation,weconservativelyevaluatedthemascracks.NUREG0619,Section4.3.2.3states,"ifrecordableindicationsareinterpretedtobecracksinanynozzle,proceedwithspargerremoval,Fl'fthenozzleboreandnozzleblendradius,andrepair."Eighteenofthetwenty-fiveindicationswereobservedat20to25%ofthedistanceamplitudecorrection e,

APPENDIXAFEEDWATERNZZLEINPETINRULTCnt'dcurve(DAC).However,theapplicableASMECoderecordingcriteriais50%DAC.Therefore,theseindicationswerenot"recordable"anddidnotrequirefurtherevaluation.Theremainingindicationsappearedtobetwoseparateflaws,onelocatedinthenozzleandonelocatedinthesafeendweld.Theindicationsappearedatapproximately50%DAC.TheflawswereaxiallyorientedandtheirsizewellwithintheASMESectionXIacceptancecriteria(a/t-4.7%and7%versusallowableof11.02%and11.23%).Theexaminationwasperformedusinga45degreeshearwavetransducercalibratedonanozzlemock-upwitha5%T-notchreflector.TheCodepermitscalibrationonnotchesupto10%T(Tisthenominalthicknessofthecalibrationblock).Consequently,theexaminationsensitivityexceedstheCoderequiredsensitivity.Ifa10%Tnotchhadbeenused,theseindicationsmaynothavebeenrecordableperASMESectionXI.ConsideringthattheexaminationwasperformedatahighersensitivitythanrequiredbyCode,thattheindicationsareatthethresholdoftherecordingcriteria,andthattheindicationswillremainwithinallowablesizeforatleastthenexttwooperatingcycles,NiagaraMohawkdeterminedthatfurtherevaluationoftheseindicationswasnotrequired.Afracturemechanicsevaluationofthesetwoflawswasperformed.Theresultsoftheanalysispredictedgrowthoftheflawsnottoexceed0,001inchesovera40-yearperiod.Therefore,theconclusionwasmadethattheflawswerenotsignificantandshouldnotaffectcontinuedplantoperation.Additionally,NiagaraMohawkcommittedtoexaminefeedwaternozzle"A"duringthenextrefuelingoutage(1993).Duringthe1993refuelingoutage(RFO-12),inserviceUTexaminationsoffeedwaternozzle"A"(N4A)Zones1,2,3,and4wereperformedbyGeneralElectricNuclearEnergy(GE-NE).Notetheindicationsidentifiedin1988(RFO-12)werecontainedinZone4ofN4A.Thesameultrasonictechniqueswereemployedasusedduringthe1988refuelingoutage(RFO-11)examinations,otherthan,thecalibrationstandardwasmodifiedtoincludeCodeallowable10%notchesaswellasthepreviouslyused5%notches.Theexaminationsindicatednoreportableindications.TheZone4indicationsdetectedinthe1988outagewereseenbutnotatrecordablelevelsbasedoneitherthe5%or10%notchcalibrations.ElectricPowerResearchInstitute(EPRI)sizingtechniqueswerethenattemptedtoseeifanadequatethrough-walldimensioncouldbeattainedonthepreviouslyrecordedindications.Althoughabasesignalcouldbeseen,notipsignalswerenotedwitheithertheRelativeArrivalTimetechniqueortheAbsoluteArrivalTimetechnique.Sincenotipcouldberesolved,thesourceofthesereflectorswasdeterminedtobefromscratchesorinsidediameter(ID)surfaceirregularitiesandnotfromIDcracking.TheseinserviceinspectionresultshavebeenreviewedandapprovedbyaNiagaraMohawkLevelIIIexaminer.

APPENDIXAFEEDWATERNOZZLEINPECTINRULTSCont'dByletterdatedJune23,1994(NMP1L0820),NMPCinformedtheCommission,andprovidedtechnicalbasisfor,utilizationoftheGEGERIS2000automatedsystem(UT)forfutureexaminationsinlieuofperformingaPT.ThisamendedourpriorNUREG0619commitment.InaletterdatedJanuary12,1995,theNRCdeterminedthatitwasacceptableforNMPCtoproceedwiththedescribedcommitmentchangesandthatNMPCwouldbeadvisedofthefinalresultsoftheNRCreview.Duringthe1995refuelingoutage(RFO-13),inserviceexaminationswereperformedonfour(4)feedwaterandthecontrolroddrivereturnlinenozzles.TheUltrasonicTest(UT)examinationswereperformedbyGE-NEandindicatednoreportableindicationswererecorded.TheseUTexaminationsutilizedtheGERIS2000automatedsystemandmanualUTpickups.AlloftheseexaminationresultshavebeenreviewedandapprovedbyaNiagaraMohawkLevelIIIexaminer,

APPENDIXAFEEDWATERNOZZLEINSPECTIONRESULTSN4ANOZZLE45DEGREENORTHEASTRESULTS19771NRI1979NRINRI1981GEOMETRICREFLECTORSWELDREPAIREDCRACKINBRACKETPIN1983*GEOMETRICREFLECTORS1984~GEOMETRICREFLECTORSGEOMETRICREFLECTORSRESULTSGEOMETRIC&NON-GEOMETRICREFLECTORS1993FO-12NRINRI1995FO-13NRIAMENDEDMETHODPERFORMEDUTNOTES:NOTREQUIREDBYNUREG-0619.PERFORMEDFORINFORMATIONONLY.THE1983SAFE-ENDREPLACEMENTOUTAGEISNOTCONSIDEREDAREFUELINGOUTAGEBYNIAGARAMOHAWK.NRIUTPTVT(I)NOREPORTABLEINDICATIONULTRASONICTESTINGDYEPENETRANTTESTINGVISUALTESTINGNOREPORTABLEINDICATIONSEITHERBEFOREORAFTERSPARGERREPLACEMENT10

APPENDIXAFEEDWATERNOZZLEINSPECTIONRESULTSN4BNOZZLE135DEGREOUTHEASTRESULTS1977119791981219831984~UTVTNRINRINRI1-1/2"LONGX314"5-1I2"LONGX0.8"DISPOSITIONEDGEOMETRICDEEPGEOMETRICDEEPAMPLITUDEASGEOMETRICREFLECTORSINCREASEOF309o8INDICATIONSDISPOSITIONEDASMINORSURFACEIRREGULARITIESNRIRESULTSVT1988FO-11GEOMETRICREFLECTORS1993FO-12NRI1995FO-13NRIAMENDEDMETHODPERFORMEDUTOTES:NOTREQUIREDBYNUREG4619.PERFORMEDFORINFORMATIONONLY.THE1983SAFE-ENDREPLACEMENTOUTAGEISNOTCONSIDEREDAREFUELINGOUTAGEBYNIAGARAMOHAWK.NRIUTPTVT(1)(2)NOREPORTABLEINDICATIONULTRASONICTESTINGDYEPENETRANTTESTINGVISUALTESTINGNOREPORTABLEINDICATIONSEITHERBEFOREORAFTERSPARGERREPLACEMENTSPARGERPULLEDFOREVALUATIONOFINDICATIONS.NEWSPARGERINSTALLED.11

APPENDIXAFEEDWATERNOZZLEINSPECTIONRESULTSN4CNOZZLE225DEGREESSOUTHWESTRESULTS19771NRINRI1979NRINRI1981GEOMETRICREFLECTORSNRI19834GEOMETRICREFLECTORS19844ACCEPTABLEINCLUSION1986FO-10GEOMETRICREFLECTORSUTGEOMETRICREFLECTORS&ACCEPTABLENON-GEOMETRICREFLECTORS1993RFO-12NRI1995FO-13NRIAMENDEDMETHODPERFORMEDUTNOTES:NOTREQUIREDBYNUREG-0619.PERFORMEDFORINFORMATIONONLY.THE1983SAFE-ENDREPLACEMENTOUTAGEISNOTCONSIDEREDAREFUELINGOUTAGEBYNIAGARAMOHAWK.NRIUTPTVT(I)NOREPORTABLEINDICATIONULTRASONICTESTINGDYEPENETRANTTESTINGVISUALTESTINGNOREPORTABLEINDICATIONSAFTERCOMPLETIONOFREPAIRACTIVITIESANDREPLACEMENTOFSPARGER.12 I

APPENDIXAFEEDWATERNOZZLEINSPECTIONRESULTSN4DNOZZLE315DEGREESNORTHWEST~~RESULTSPT19771NRINRINRI1979NRI1981GEOMETRICREFLECI'ORSNRI1983*TWOINDICATIONSNOTGEOMETRIC25%FSH1984+NRI1986FO-10GEOMETRICREFLECTORSRESULTSUTVT1988RFO-11GEOMETRICREFLECTORSNRI1993FO-12NRI1995FO-13NRIAMENDEDMETHODPERFORMEDUTNOTES:NOTREQUIREDBYNUREG4619.PERFORMEDFORINFORMATIONONLY.THE1983SAFE-ENDREPLACEMENTOUTAGEISNOTCONSIDEREDAREFUELINGOUTAGEBYNIAGARAMOHAWK.NRIUTPTVT(1)NOREPORTABLEINDICATIONULTRASONICTESTINGDYEPENETRANTTESTINGVISUALTESTINGNOREPORTABLEINDICATIONSAFTERCOMPLETIONOFREPAIRACTIVITIESANDREPLACEMENTOFSPARGER.13

APPENDIXACONTROLRODDRIVERETURNLINENOZZLEINSPECTIONRTN9NOZZLE44.1-WD417/01S-IRRESULTS19771197919811983~19848'986FO-10NRIRESULTS1988FO-111993RFO-121995FO-13NRIAMENDEDMETHODPERFORMEDUTNOTES:NOTREQUIREDBYNUREG-0619.PERFORMEDFORINFORMATIONONLY.THE1983SAFE-ENDREPLACEMENTOUTAGEISNOTCONSIDEREDAREFUELINGOUTAGEBYNIAGARAMOHAWK.NRIUTPTVT0)NOREPORTABLEINDICATIONULTRASONICTESTINGDYEPENETRANTTESTINGVISUALTESTINGNOREPORTABLEINDICATIONSEITHERBEFOREORAFTERSPARGERREPLACEMENT14

~~4APP~~IX3MODIFICATIONORSYSTEMCHANGESAFFECTFEEDATERFLWORTEMPERAE1997.Feedwaternozzlecladdingremovedandspargersreplacedwithimproveddesign.~179ReactorWaterCleanupreturnlinereroutedtothefeedwaterlineinaccordancewithSection4.2ofNUREG-0619.1981ReplacedsoutheastspargerafterevaluationofUTindications.1983Thefeedwaterlowflowcontrolvalveswerereplacedwithnewvalvesdesignedtoimprovecontrolatlowflowconditions.Inaddition,asix-inchrecirculationlinewasinstalledtoprovideimprovedflowcontrolofthefeedwatersystem.Thesemodificationswerepreviouslydescribedinourletterdated9/8/81.19914InresponsetoNUREG0737,ActionItemII.D.1,instrumentandcontrolequipmentwereinstalledtoprovideahighreactorleveltripofthemotor-drivenfeedwaterpumps.Inaddition,theHPCIcontrolsystemwasmodifiedtoaddannunciatoralarmsforlossofHPCIfailuresignalinstandbymode.1998iThefollowingchangesweremadetoimprovethereliabilityofthefeedwatersystem:1.Modifiedhighleveltripcircuitsealinlogic.2.Modifiedmainflowvalvelockupcircuitstowithstandmomentarypowerinterruptions.3.Modifiedlogictoclose6-inchrecirculationvalveonpumpstartsignalforrunoutprotection.4.ModifiedlogictocloselowflowcontrolvalvesonHPCIinitiation.199Noadditionalmodificationsorsystemchangesthataffectfeedwaterflowortemperature.~193Turbinedrivenfeedwaterpumpflowcontrolvalveswerereplacedbyasingleflowcontrolvalve;thischangehadnoaffectonfeedwaterflowortemperature.~195Noadditionalmodificationsorsystemchangesthataffectfeedwaterflowortemperature.15

APPENDIXCDESCRIPTIONOFTRANIEXAMINATINPRCEDA.IIXILPPWM~TheNESfeedwaternozzleUTexaminationprocedurewasfirstusedatNineMilePointUnit1in1981.Thisproceduredividedthenozzleinnerradiusandboresurfacesintotwozones,NESZone1examinationsareperformedfromthereactorvesselshell;NESZone2examinationsareperformedfromthenozzlebarrel.NESZone1andZone2examinationsoverlapattheinsideradiussurfaceofthenozzle.Examinationsperformedfromthereactorvesselshellareperformedbyattachingaspeciallydesignedlucitewedge,whichconformstothereactorvesseloutsideradius,toanultrasonictransducersuchthatthelongitudinalbeamangleisfixed.Examinationsperformedfromthenozzlebarrelareperformedusingcompoundanglebeamshearwavetechniques.Inthiscase,anumberofspeciallydesignedfixedcompoundanglelucitewedgeswhichconformtotheoutsideradiusofthenozzlebarrelareused.In1988,additionalscansandscanningangleswereusedonthesafe-endbore,nozzlebore,andtheinnerradiustoensureoptimalinterrogationoftherequiredvolumes.Recordingcriteriawasupdatedformoreuniformitywhencomparingdatafromeachoutage.Anewtemplatewasdesignedandbuilttofacilitateshell-sideexams.B.~GEPC.URBTheGEfeedwaternozzleUTexaminationprocedurewasusedforthe1977baselineandthe1979inserviceinspectionsatNineMilePointUnit1.Thisproceduredividesthenozzleinnerradiusandboresurfacesintothreezones.TheGEZone1examinationisperformedbyattachinganultrasonictransducertoaspeciallydesignedlucitewedge,whichconformstothereactorvesseloutsideradius,suchthatthelongitudinalbeamangleandthecircumferentialbeamanglearefixed.TheGEZone2examinationisperformedbyattachinganultrasonictransducertoaspeciallydesignedlucitewedge,whichconformstotheouterdiameterblendradiusofthenozzle,suchthatthelongitudinalbeamangleandthecircumferentialbeamanglearefixed.TheGEZone3examinationisperformedbyattachinganultrasonictransducertoaspeciallydesignedlucitewedge,whichconformstotheoutsideradiusofthenozzlebarrel,suchthatthecircumferentialbeamangleisfixed.16

tAPPENDIXCDESCRIPTIONOFULTRANICEXAMINATIONPROCEDURC.NMPCPROCEDURENiagaraMohawkNDEProcedure(No.NDEP-UT-6.07)wasusedtoUTexaminefeedwaternozzle"A"(N4A)Zones1,2,3,and4duringthe1993refuelingoutage(RFO-12).ThisprocedureutilizedmanualtechniquesandequipmentwhicharesimilarandequivalenttothoseusedbyNESduringthe1988refuelingoutage(RFO-11).TheultrasonictechniquesemployedarethesameasthoseusedfortheRFO-11examinations,otherthan,thecalibrationstandardwasmodifiedtoincludeCodeallowable10%notchesaswellasthepreviouslyused5%notchesforthesafe-endboreexamination.TheseexaminationswereperformedbyGeneralElectricNuclearEnergy(GE-NE)personnel.D.DESCRIPTIONOFGE-NEGERIS-2000AUTOMATEDVTINSPECTINYTEMF-13TheGERIS-2000UTImagingSystemisanautomatedultrasonicdataacquisitionandimagingsystem.AutomatedscannersinterfacedtotheGERIS-2000,movedUTtransducersradiallyandcircumferentiallyaroundtheoutsidesurfaceofthenozzleandadjacentsurfacesofthesafe-endandreactorpressurevessel.UTdatawascollectedandstoredindigitalformat.ThecompleteRFwaveformwasdigitizedandrecordedonopticaldisksforanalysis,TheGERIS-2000UTsubsystemisamultiplexedlogarithmicUTflawdetectioninstrument.Foreachchannel,thecompleteRFA-scanwasdigitizedandstoredonopticaldisks.ThesystemstorestheRFsignalinlogarithmicformatthathasaninstantaneousdynamicrangethatisgreaterthan85dB.ThelogarithmicUTsystemallowstherecordingofthepeaksoflowandhighamplitudeUTsignalsatthesametimewithoutclippingUTsignals,suchaswouldoccurwithlinearsystemsthathaveaninstantaneousdynamicrangegenerallylessthan45dB.TheanalysisoftheGERIS-2000datautilizedadvancedinteractivecolorgraphicstoevaluateandassistincharacterizingindicationsfromservice,fabricationandgeometricrelatedUTreflectors.CoordinatedA-,B-,C-,volumetricside-view-,volumetricend-view-,and3D-scansareprovidedonahighresolution(1280by1024pixels)colordisplay.Severalchannelsmaybedisplayedatonetimetocorrelateindicationsfromdifferentchannels.Thesegraphicdisplayshaveanadjustablecolorscalethatprovidesthebestresolutionofflawdetectionandcharacterizationdowntothematerialnoise.NMPCsubmittalofJune23,1994tReference¹13]includedEnclosure1,SectionII,"UltrasonicInspectionTechniques",whichprovidedadescriptionoftheGERISUTtechniques,UTinstrumentationandscanningequipmentindetail.17

tAPPENDIXCDESCRIPTIONOFULTRANICEXAMINATINPROCEDURESCont'dD.DCRIPTIONFE-NEGERT-2000AUTMATEDVTINPECTIONSYSTEMCont'dAmplitude-basedrecordingandreportingcriteriaisnotusedwiththeGERIS-2000fornozzleinnerradiusandboreexaminations.AllUTdataisrecordedandevaluated.AnyUTdatathathassignal-to-noiseratiosofgreaterthan2-to-l,hasecho-dynamiccharacteristicsofcrackingandcanbeconfirmedfrom2directionsoraccompaniedbytip-diffractedsignalsarecalledcracks.TheGERIS-2000systemiscapableofdetectingandsizingaxialflaws0.250inchesorlessindepthinfeedwaternozzleinnerradiusandboreregions.ThecapabilityoftheGERIS-2000systemfordefectdetectionandsizingwasdemonstratedandincludedinNMPCsubmittalJune23,1994[Reference¹13]inEnclosure1,SectionIII,"UltrasonicTechniqueQualificationPlan",whichprovidedadetaileddescriptionoftheEDMnotchesandfatigue-crackimplantsthatareusedtodemonstratethecapabilityoftheGERIS-2000system.Whenobstructionslimitedautomatedscanningcoverage,supplementalmanualexaminationswereperformed.Inbothcases,fullIDcoveragewasobtainedfromatleastonedirection.Whenautomatedscanningcannotbeperformedfrombothdirections,manualtechniquesutilizingthesametechniquesastheautomatedexaminationswereused.TheentireIDsurfaceofzones1through5(seeFigure1below)wereexaminedforaxialflawsfromatleast1directionwitheitherautomatedormanualtechniques.Areasexaminedwerefullydocumentedintheinspectionresults.ThemethodusedtoensurethattheNMP1feedwaternozzlesareexaminedwithequivalenttechniquesisthroughtheuseofmodeling.ThemodelingusedwaswheretheUTbeampathsarepredictedusingraytracingalgorithmswithpredeterminedbeamangleparameters.ThebeampathsareusedtodeterminetheincidentanglesofthebeamontheIDsurfaces.TheincidentanglesoftheUTbeamontheIDsurfacesusedontheNMP1feedwaternozzlewerecomparabletotheGEqualificationmockups.Multipleangle-beamtransducersdesignedfrom"asbuilt"andfabricationwereusedtofullyexaminezones1through5.18 r

~N4'APPENDIXCDESCRIPTIONOFULTRASNICEXAMINATIONPROCEDURESCont'dVESSELINOZZLE)SAFEEND~BB,/l4B44,4BlFigure1-NouleExaminationZones19 F