ML010100519

Interim Guidance for In-situ Pressure Testing Pertaining to Pressurization Rate

ML010100519
Person / Time
Issue date:	01/05/2001
From:	Sheron B NRC/NRR/ADPT
To:	Modeen D Nuclear Energy Institute
Karwoski K
References
TAC MA4265
Download: ML010100519 (2)

Text

January5,2001DavidJ.Modeen,DirectorEngineering NuclearGenerationDivision NuclearEnergyInstitute 1776IStreet,NWSuite400 Washington,DC20006-3708

SUBJECT:

INTERIMGUIDANCEFORIN-SITUPRESSURETESTINGPERTAININGTOPRESSURIZATIONRATE

DearMr.Modeen:

ByletterdatedNovember8,2000,"InterimGuidanceforInSituPressureTesting"(ADAMSAccessionNumberML003770571),youprovidedthestatusofyourevaluationoftheArkansas NuclearOneUnit2(ANO-2)steamgeneratortubepressuretestingresultswhichincluded interimguidanceontheconductofin-situpressuretests.Thisguidanceincludedspecifyinga maximumpressurizationrateof200poundspersquareinch(psi)persec,addingadditional holdpointsduringtheconductofthetest,andspecifyingaminimumholdtimeoftwominutesto verifycrackstability.Iunderstandthefinalreportdocumentingyoureffortswillbepublishedin2001.ConsistentwithNRCcommentsatapublicmeetingonSeptember28,2000,(seemeetingsummarydated October,12,2000,"SummaryofSeptember28,2000,MeetingwiththeNuclearEnergy Institute(NEI)RegardingSteamGeneratorTubeBurstIntegrity"-ADAMSAccessionNumber ML003760794),theNRCstaffwillwanttoreviewthereportbeforemakinganyconclusionson thistopic.Intheinterim,themodificationsyou'veproposedtothein-situpressuretesting guidelinesappearappropriate.Inyourletter,youindicatedtheunexpectedtestresultsrelatetoanycrack,greaterthanthethrough-wallcriticalcracklength,thatcontainscracksegmentsgreaterthan90%through-wall, butthattheabsenceoftherateeffectatveryslowratesofpressurizationhasnotbeen specificallydemonstratedforotherdefectmorphologies.Nonetheless,youconcludedthere wasnodependencyonpressurizationrateinanyoftheindustrystandardcorrelationdatasets.

Regardingtheseconclusionsandobservations,itwouldbebeneficialifyoufurtherclarifiedtheir basisinyourreportinlightofthefactthattheabsenceofthepressurizationeffecthasnotbeen specificallydemonstratedforotherdefectmorphologiesindicatingtotheNRCstaffthatthe potentialexistsforthecorrelationstobeaffected.AttheSeptember28,2000,meeting,theindustryindicateditwouldconsiderdoingsomeverificationtestingoftheirhypothesesregardingthenecessaryflawmorphologyforobservation ofthepressurizationeffect.Wewouldbeinterestedinhearingtheoutcomeofthisactivity.

DavidJ.Modeen-2-Insummary,theNRCstaffbelievestheNEIinitiativeisprudentgiventheresultsoftheANO-2pressuretestsandweappreciateyoureffortsonthismatter.Ifyouwouldliketodiscussanyof thisinformationinmoredetail,pleasecontactJackStrosniderat(301)415-3298.Sincerely,/ra/BrianW.Sheron,AssociateDirectorforProjectLicensingandTechnicalAnalysisOfficeofNuclearReactorRegulation cc:JimRiley,NEI RalphBeedle,NEI DavidJ.Modeen-2-Insummary,theNRCstaffbelievestheNEIinitiativeisprudentgiventheresultsoftheANO-2pressuretestsandweappreciateyoureffortsonthismatter.Ifyouwouldliketodiscussanyof thisinformationinmoredetail,pleasecontactJackStrosniderat(301)415-3298.Sincerely,BrianW.Sheron,AssociateDirectorforProjectLicensingandTechnicalAnalysisOfficeofNuclearReactorRegulation cc:JimRiley,NEI RalphBeedle,NEIDistributionEMCBRFSCoffinRRothmanAKeim EMurphyCBeardslee REnnisLLund ZFuJTsao JBirmingham SNewberryDOCUMENTNAME:C:\NEIletteronpressurizatio~.wpdINDICATEINBOX:"C"=COPYW/OATTACHMENT/ENCLOSURE,"E"=COPYW/ATT/ENCL,"N"=NOCOPYOFFICEEMCB:DEEEMCB:DEEEMCB:DENAMEKKarwoski:kkESullivan:ejsWBateman:whbDATE12/22/0012/22/0012/22/00OFFICEDD:DE:NRRD:DE:NRRAD:ADPT:NRRNAMERHWessman:rhwJRStrosnider:jrsBWSheron:bws:DATE12/29/001/02/011/05/01OFFICIALRECORDCOPY