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| document type = CORRESPONDENCE-LETTERS, INCOMING CORRESPONDENCE, UTILITY TO NRC
| document type = CORRESPONDENCE-LETTERS, INCOMING CORRESPONDENCE, UTILITY TO NRC
| page count = 6
| page count = 6
}}
=Text=
{{#Wiki_filter:QvOb..REGULATORINFORMATIONDISTRIBUTIONTEMDOCKETNBR.-50-250/251~RKEYPT3/4DQCDATE:781115RECIPIENT:ACCESSIONNBR:7811210338ORIGINATOR-UHRIG,R.E.COPIESRECEIUED:COMPANY.FLPVR&LIGHTLTR3ENCL
==SUBJECT:==
SIZE:4RequestsrelieffromASMECodeReqsreUltrasonicExaminationsofPipingWelds.Recording&evalindicationsat20%DACisimpractical.Primaryreferencelevel(100%DAC)criteriaforUTexaminationprovidescomparable'afety'evel.'1STRTPIITIQNCOOEt800bQIST@IPLITI()NTITLE'!RFa(IESTSFOREXEI.PTIOTAS(ALITYPES)NOTARIZEDBRCHIEF'ROJv(:RF'4RCPrRLEJI"ILI.E>T~BELLI.PDRACRSTOT>LN(jPHERENCL7w/ENCLHIE'>CL'w/ENCLiu/ENCLw/FNCL>'/2ENCLW/ENCLw/P'NCL~~Al2.6Hc~w/1bENCLQFCOPIESREQUIRED!LTRENCLIFORACTIONDEISENHUTORB//1BGRIMESORB(f4BCPERICKSONORB(/4LA2b26IOY2pHieNOTES:
P.O.BOX013100,MIAMI,FL33101FLORIDAPOWER&LIGHTCOIiIPANYOfficeofNuclearReactorRegulationAttention:Mr.VictorStella,DirectorDivisionofOperatingReactorsU.S.NuclearRegulatoryCommissionLlashington,D.C.20555
==DearMr.Stello:==
November15,1978L-78-361Re:TurkeyPointUnits3&4,St.LucieUnit1DocketNos.50-250,50-251&50-33510CFR50.55a(g)(5),RequestforReliefUltrasonicExaminationsofPiinMeldsFloridaPower&LightCompanyhasdeterminedthatconformancewithcertaincoderequirementsconcerningultrasonicexaminationofpipingweldswouldbeimpracticalforTurkeyPointUnits3&4andSt.LucieUnitl.Therefore,pursuantto10CFR50.12and10CFR50.55a(g)(5),arequestforrelieffromthecoderequirements,includinginformationinsupportofourdetermination,isattached.Additionalrequestsforreliefarebeingconsidered,buthavenotbeencompletelyformulatedatthistime.Forexample,asaresultofmeetingswiththeNRCstaffatourcorporateheadquartersduringtheperiodMay3-5,1978,itwasdeterminedthatsomevalvesinthevalvetestingprogramwerenosafetyrelated,sotheyweredeletedfromtheprogram.Therefor,weareconsideringarequesttoexemptthesystemsandcomponentscontiguouswiththesenon-safetyrelatedvalvesfromtheexaminationrequirementsoftheinserviceinspectionprogram.Additionalrequestsforreliefwillbeforwardedtoyourofficeastheyaredeveloped.Veryt1yours,RobertE.UhrigVicePresidentREU/MAS/cpcAttachmentcc:Mr.JamesP.O'Reilly,RegionIIHaroldF.Reis,EsquiregalV811210'~&iqPEOPLE...SERVINGPEOPLE ATTACHi~1ENTRe:TurkeyPointUnits3&4andSt.LucieUnit1DocketNos.50-250,50-251,and50-335ReuestforRelieffromAS?4ECodeReouirementsI.APPLICABILITYFloridaPower&LightCompanyrequestsrelieffromthebelowlistedCodeRequirementsastheyapplytoultrasonicexaminationofpipingweldsatTurkeyPointUnits3&4andSt.LucieUnit1(Class1&2).II.CODEREQUIREMENTSA.ASNECodeSectionXI(1974Edition),ParagraphIWA-2232,UltrasonicExamination:"UltrasonicexaminationshallbeconductedinaccordancewiththeprovisionsofAppendixI.WhereAppendixI(I-1200)isnotapplicable,theprovisionsofArticle5ofSectionVshallapply."B.ASNECodeSectionV(1974'Edition),ParagraphT-537,EvaluationofIndications:"Allindicationswhichproducearesponsegreaterthan20percentofthereferencelevelshallbeinvestigatedtotheextent.thattheoperatorcanevaluatetheshape,identity,andlocationofallsuchreflectorsintermsoftheacceptance-rejectionstandardsofthereferencingCodeSection."III.BASISFORRELXEFA.The20%DAC(distance-amplitudecorrection)criteriaofparagraphT-537ofSectionVisimpractical.IV.B.Theprimaryreferencelevel(100%DAC)criteriafortheultrasonic(UT)examinationofpipingweldsprovidesalevelofsafetycomparabletotheSectionVstandards.DISCUSSXONA.Recordingandevaluatingindicationsat20%DACisimpracticalforthefollowingreasons:1.TheweldedjointsinnuclearpipingfrequentlycontainCodeallowablewallthicknessdifferences(12%ofnominalthickness)aswellassomewelddrop-through,counterboretaper,crownheight,etc.TheseconditionsgenerateanextremelylargenumberofgeometricreflectorswhichproduceUTindicationsgreaterthan20%DAC.
2.Weldmetalinstainlesssteelpipingcontainsreflect,-orsduetothemetallurgicalstructurewhichproducealargenumberofUTindications.3.Althoughstresscorrosioncrackinginstainlesssteelhasbeenfoundtoexistinlowlevelamplitudes,experiencehasshownthatthetypicalmodeoffailureinthistypeofcrackingisnotintheweldmetalperse,butintheheataffectedzone(HAZ)andbasemetalofthepipe.AnexperiencedUToperatorcandiscriminatestresscorrosioncracksfromgeometricandmetallurgicalreflectors.Thus,itisnotneces-sarytorecordandevaluateallreflectorsasSectionVrequires,butonlythosewhicharerealflaws.ItshouldalsobenotedthattherecordingofrealflawsisdoneregardlessofCodeevaluationcriteria(insofaraspercentageofDACisconcerned)aspartofgoodexaminationpractice.4.Allexaminationpersonnelexperienceradiationex-posureduringinserviceexaminations.TheSectionVrequirementtorecordandevaluateUTindicationsatthe20%DACplacesanunnecessaryburdenonthelimit-ednumberofexperiencedandqualified.examiners=availabletotheowner.B.Theprimaryreferenceevaluation(100%DAC)ofindicationsestablishesanadequatelevelofinformationforthefol-lowingreasons:Historically,SectionXIestablishesthe20%DACeval-uationcriteriabyreferencingotherSectionsotheASNECode.Forexample,ParagraphIS-213.2ofthe1970Codeandthe1971CodereferencesAppendixIXofSectionIII.Also,asquotedaboveinpart.IIofthisAttachment,ParagraphIPlA-2232ofthe=1974Codereer-encesArticle5ofSectionV.Until1976,.-.when10CFR50.55a(g)requiredinserviceinspectionprogramstobeupgradedtothe1974EditionofSectionXI,mostoftheseprogramshadbeenconductedinaccordancewithParagraphIS-213.2oftheSummer1971AddendatoSectionXI.Theseprogramsinvokedthe100%DACevaluationcriteriaandtookexceptiontothe20%DACevaluationcriteriaofAppendixIXofSectionIII.Suchprogramswereverysuccessfulandprovidedacomprehensivesafety,levelforthecomponentsexamined.2.TheSummer1973AddendaandtheWinter1975Addenda,withtheintroductionofAppendixIforvesselUTexaminationandAppendixIIIforpipingUTexamination,confirmedtheASNESectionXICommitteepositionon50-:-DACrecordingand100%DACevaluationofUTindications.Inaddition,the100%DACevaluationcriteriaforindic-ationsfoundduringUTexaminationofpipingweldswasreconfirmedbythe1977EditionoSectionXI[ParagraphINA-2232(b)(l)andIII-4500(1)].
V.ALTERNATIVEEVALUATIONCRITERIAA.Indications50%ofDACorgreatershallberecorded.B.Anyindication100%ofDACorgreatershallbeinvest-igatedbyaLevelIIorLevelIIIexaminertotheextentnecessarytodeterminetheshape,identity,andlocationofthereflector.C.Anynon-geometricindication,regardlessofDAC,discoveredduringtheUltrasonic(UT)examinationofpipingweldsandbasemetalmaterialsshallberecordedandinvestigatedbyaLevelIIorLevelIIIexaminertotheextentnecessarytodeterminetheshape,identity,andlocationofthereflector.D.Theownershallevaluateandtakecorrectiveactionforthedispositionofanyindicationinvestigatedandfoundtobeotherthangeometricinnature.
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}}
}}

Revision as of 18:48, 26 April 2018

Requests Relief from ASME Code Requirements Re Ultrasonic Examinations of Piping Welds.Recording & Eval Indications at 20% DAC Is Impractical.Primary Reference level(100% DAC) Criteria for UT Exam Provides Comparable Safety Level
ML17206A516
Person / Time
Site: Saint Lucie, Turkey Point  NextEra Energy icon.png
Issue date: 11/15/1978
From: UHRIG R E
FLORIDA POWER & LIGHT CO.
To: STELLO V
Office of Nuclear Reactor Regulation
References
L-78-361, NUDOCS 7811210338
Download: ML17206A516 (6)


Text

QvOb..REGULATORINFORMATIONDISTRIBUTIONTEMDOCKETNBR.-50-250/251~RKEYPT3/4DQCDATE:781115RECIPIENT:ACCESSIONNBR:7811210338ORIGINATOR-UHRIG,R.E.COPIESRECEIUED:COMPANY.FLPVR&LIGHTLTR3ENCL

SUBJECT:

SIZE:4RequestsrelieffromASMECodeReqsreUltrasonicExaminationsofPipingWelds.Recording&evalindicationsat20%DACisimpractical.Primaryreferencelevel(100%DAC)criteriaforUTexaminationprovidescomparable'afety'evel.'1STRTPIITIQNCOOEt800bQIST@IPLITI()NTITLE'!RFa(IESTSFOREXEI.PTIOTAS(ALITYPES)NOTARIZEDBRCHIEF'ROJv(:RF'4RCPrRLEJI"ILI.E>T~BELLI.PDRACRSTOT>LN(jPHERENCL7w/ENCLHIE'>CL'w/ENCLiu/ENCLw/FNCL>'/2ENCLW/ENCLw/P'NCL~~Al2.6Hc~w/1bENCLQFCOPIESREQUIRED!LTRENCLIFORACTIONDEISENHUTORB//1BGRIMESORB(f4BCPERICKSONORB(/4LA2b26IOY2pHieNOTES:

P.O.BOX013100,MIAMI,FL33101FLORIDAPOWER&LIGHTCOIiIPANYOfficeofNuclearReactorRegulationAttention:Mr.VictorStella,DirectorDivisionofOperatingReactorsU.S.NuclearRegulatoryCommissionLlashington,D.C.20555

DearMr.Stello:

November15,1978L-78-361Re:TurkeyPointUnits3&4,St.LucieUnit1DocketNos.50-250,50-251&50-33510CFR50.55a(g)(5),RequestforReliefUltrasonicExaminationsofPiinMeldsFloridaPower&LightCompanyhasdeterminedthatconformancewithcertaincoderequirementsconcerningultrasonicexaminationofpipingweldswouldbeimpracticalforTurkeyPointUnits3&4andSt.LucieUnitl.Therefore,pursuantto10CFR50.12and10CFR50.55a(g)(5),arequestforrelieffromthecoderequirements,includinginformationinsupportofourdetermination,isattached.Additionalrequestsforreliefarebeingconsidered,buthavenotbeencompletelyformulatedatthistime.Forexample,asaresultofmeetingswiththeNRCstaffatourcorporateheadquartersduringtheperiodMay3-5,1978,itwasdeterminedthatsomevalvesinthevalvetestingprogramwerenosafetyrelated,sotheyweredeletedfromtheprogram.Therefor,weareconsideringarequesttoexemptthesystemsandcomponentscontiguouswiththesenon-safetyrelatedvalvesfromtheexaminationrequirementsoftheinserviceinspectionprogram.Additionalrequestsforreliefwillbeforwardedtoyourofficeastheyaredeveloped.Veryt1yours,RobertE.UhrigVicePresidentREU/MAS/cpcAttachmentcc:Mr.JamesP.O'Reilly,RegionIIHaroldF.Reis,EsquiregalV811210'~&iqPEOPLE...SERVINGPEOPLE ATTACHi~1ENTRe:TurkeyPointUnits3&4andSt.LucieUnit1DocketNos.50-250,50-251,and50-335ReuestforRelieffromAS?4ECodeReouirementsI.APPLICABILITYFloridaPower&LightCompanyrequestsrelieffromthebelowlistedCodeRequirementsastheyapplytoultrasonicexaminationofpipingweldsatTurkeyPointUnits3&4andSt.LucieUnit1(Class1&2).II.CODEREQUIREMENTSA.ASNECodeSectionXI(1974Edition),ParagraphIWA-2232,UltrasonicExamination:"UltrasonicexaminationshallbeconductedinaccordancewiththeprovisionsofAppendixI.WhereAppendixI(I-1200)isnotapplicable,theprovisionsofArticle5ofSectionVshallapply."B.ASNECodeSectionV(1974'Edition),ParagraphT-537,EvaluationofIndications:"Allindicationswhichproducearesponsegreaterthan20percentofthereferencelevelshallbeinvestigatedtotheextent.thattheoperatorcanevaluatetheshape,identity,andlocationofallsuchreflectorsintermsoftheacceptance-rejectionstandardsofthereferencingCodeSection."III.BASISFORRELXEFA.The20%DAC(distance-amplitudecorrection)criteriaofparagraphT-537ofSectionVisimpractical.IV.B.Theprimaryreferencelevel(100%DAC)criteriafortheultrasonic(UT)examinationofpipingweldsprovidesalevelofsafetycomparabletotheSectionVstandards.DISCUSSXONA.Recordingandevaluatingindicationsat20%DACisimpracticalforthefollowingreasons:1.TheweldedjointsinnuclearpipingfrequentlycontainCodeallowablewallthicknessdifferences(12%ofnominalthickness)aswellassomewelddrop-through,counterboretaper,crownheight,etc.TheseconditionsgenerateanextremelylargenumberofgeometricreflectorswhichproduceUTindicationsgreaterthan20%DAC.

2.Weldmetalinstainlesssteelpipingcontainsreflect,-orsduetothemetallurgicalstructurewhichproducealargenumberofUTindications.3.Althoughstresscorrosioncrackinginstainlesssteelhasbeenfoundtoexistinlowlevelamplitudes,experiencehasshownthatthetypicalmodeoffailureinthistypeofcrackingisnotintheweldmetalperse,butintheheataffectedzone(HAZ)andbasemetalofthepipe.AnexperiencedUToperatorcandiscriminatestresscorrosioncracksfromgeometricandmetallurgicalreflectors.Thus,itisnotneces-sarytorecordandevaluateallreflectorsasSectionVrequires,butonlythosewhicharerealflaws.ItshouldalsobenotedthattherecordingofrealflawsisdoneregardlessofCodeevaluationcriteria(insofaraspercentageofDACisconcerned)aspartofgoodexaminationpractice.4.Allexaminationpersonnelexperienceradiationex-posureduringinserviceexaminations.TheSectionVrequirementtorecordandevaluateUTindicationsatthe20%DACplacesanunnecessaryburdenonthelimit-ednumberofexperiencedandqualified.examiners=availabletotheowner.B.Theprimaryreferenceevaluation(100%DAC)ofindicationsestablishesanadequatelevelofinformationforthefol-lowingreasons:Historically,SectionXIestablishesthe20%DACeval-uationcriteriabyreferencingotherSectionsotheASNECode.Forexample,ParagraphIS-213.2ofthe1970Codeandthe1971CodereferencesAppendixIXofSectionIII.Also,asquotedaboveinpart.IIofthisAttachment,ParagraphIPlA-2232ofthe=1974Codereer-encesArticle5ofSectionV.Until1976,.-.when10CFR50.55a(g)requiredinserviceinspectionprogramstobeupgradedtothe1974EditionofSectionXI,mostoftheseprogramshadbeenconductedinaccordancewithParagraphIS-213.2oftheSummer1971AddendatoSectionXI.Theseprogramsinvokedthe100%DACevaluationcriteriaandtookexceptiontothe20%DACevaluationcriteriaofAppendixIXofSectionIII.Suchprogramswereverysuccessfulandprovidedacomprehensivesafety,levelforthecomponentsexamined.2.TheSummer1973AddendaandtheWinter1975Addenda,withtheintroductionofAppendixIforvesselUTexaminationandAppendixIIIforpipingUTexamination,confirmedtheASNESectionXICommitteepositionon50-:-DACrecordingand100%DACevaluationofUTindications.Inaddition,the100%DACevaluationcriteriaforindic-ationsfoundduringUTexaminationofpipingweldswasreconfirmedbythe1977EditionoSectionXI[ParagraphINA-2232(b)(l)andIII-4500(1)].

V.ALTERNATIVEEVALUATIONCRITERIAA.Indications50%ofDACorgreatershallberecorded.B.Anyindication100%ofDACorgreatershallbeinvest-igatedbyaLevelIIorLevelIIIexaminertotheextentnecessarytodeterminetheshape,identity,andlocationofthereflector.C.Anynon-geometricindication,regardlessofDAC,discoveredduringtheUltrasonic(UT)examinationofpipingweldsandbasemetalmaterialsshallberecordedandinvestigatedbyaLevelIIorLevelIIIexaminertotheextentnecessarytodeterminetheshape,identity,andlocationofthereflector.D.Theownershallevaluateandtakecorrectiveactionforthedispositionofanyindicationinvestigatedandfoundtobeotherthangeometricinnature.

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