ML17037C271

Nine Mile Point Unit 1 - Letter Enclosing a Report on Environmental Qualification Test Results Applicable to the Main Steam Isolation Valve Position Switch

ML17037C271
Person / Time
Site:	Nine Mile Point
Issue date:	07/29/1975
From:	Rhode G K Niagara Mohawk Power Corp
To:	Rusche B C Office of Nuclear Reactor Regulation
References
Download: ML17037C271 (12)

Text

NRCDISTRIBUTIONFORf'ART50DOCKETMATERIAL(TEMPORARYFORM)fROMagaraoawoweroSyracuse,N.Y,GeraldKRhodes'ATEQFDOC7-29-75DATEREC'D8>>4-75'TRCONTROLNO:FI)E'WXRPTOTHERTO:BernardC.RuscheORIG1SignedCCOTHERSENTNRCPDRSENTLOCALPDRCLASSUNCLASSPROPINFOXXXxINPUTNOCYSREC'DDOCKETNO:50-220DESCRIPTION:Ltr,transthefoll'owing.o,ENCLOSURES:MainSteamIsolationValvePositionSwit.eh,Enviro.TestRePort,~~~..rplANTNAME.NineMlePoint81(1cy,EncloRec'd)'DONOTR@MPV@FORACTION/INFORMATIONVCR9-29-75BUTLER(L)W/CopiesCLARK(L)W/CopiesPARR(L)W/CopiesKNIEL(L)~W/CopiesSCHWENCER(L)W/CopiesSTOLZ(L)W/CopiesVASSALLO(L)W/CopiesPURPLE(L)W/CopiesZIEMANN(L)W/CopiesDICKER(E)W/Copies-KNIGHTON(E)W/CopiesYOUNGBLOODW/Copies~REGAN(E)W/CopiesEAR(L)'W/ssCopiesSPMSW/Copies(E)LPMW/op(esREID(L)W/COPIESINTERNALDISTRIBUTIONRCPDROGC,ROOMP-506AGOSSICK/STAFFCASEGIAMBUSSOBOYDMOORE(L)DEYOUNG(L)SgOVHOLT(L);,yCOLLER(L)(Ltr)~P.COLLINSDENISEEGOPRFILE5REGION(2)MIPCDENTONGRIMES(iAMMILLKASTNERBALLARDSPANGLERTECHREVIEWSHROEDERACCARYKNIGHTPAWLICKISHAO@%TELLOHOUSTONp4OVAKROSSIPPOLITOTEDESCOJ,COLLINSLAINASBENAROYAVOLLMERENVIROMULLERDICKERKNIGHTONYOUNGBLOODBEGANPRJECTLD~HARLESSLICASSTR.DIGGS(L)H.GEARIN(L)E.GOULBOURNE(L)P.KREUTZER(E)J.LEE(L)M.RU3HBROOK(L)S.REED(E)M.SERVICE(I)S.SHEPPARD(L)M.SLATER(E)SMITH(L)'.TEETS(L)G.WILLIAMS(E)V.WILSON(L)R.INGRAM(L)M.DUNCANA/TIND~BRAITMANSALTZMANMELTZPLANSMCDONALDCHAPMANDUBE(Ltr)E.COUPEPETERSONHARTFIELD(2)KLECKEREISENHUTWIGGINTON"'"":"""""""'XTERN'AsL"DIS:IBUTIQN'-",".'<"":.-.;.'.:-'..:...'.'~.xs."..-'.-..."..-.;.~~~..".-',,',-LOCALPDRW-TIC(ABERNATHY)(12)(10)-ATIONALLABS~-NSIC(BUCHANAN).,1,-W.PENNINGTON,RmE-201GT1-ASLB1-CONSULTANTS1-NewtonAnderson,NEWMARK/BLUME/AGBABIAN/5ACRSH8L~~/SENT~~~&=/1-PDR-SAN/LA/NY1-BROOKHAVENNATLAB1-G.URIKSONORNL

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,RegulatoryDockatF'l~NIAGARAMOHAWKPOWERCORPORATON.1II1IM;NIAGARAI'OHAWK300ERIEBOULEVARDWESTSYRACUSE.N.Y.132023~'1JcYa+r00Spy,u~aeV"'-g~lhO"R,ouoacIeiJuly29,1975Mr.BernardC.Rusche,DirectorOfficeofNuclearReactorRegulationsU.S.NuclearRegulatoryCommissionWashington,D.C.20555Be:NineMilePointUnit¹1DocketNo.50-220j

DearMr.Rusche:

AreportonenvironmentalqualificationtestresultsapplicabletothemainsteamisolationvalvepositionswitchatNineMilePointUnit¹1isattached.ThisreportisintendedtofulfillthecommitmentmadeinAmendmentNo.2tothe"ApplicationtoConvertProvisionalOperatingLicensetoFull-TermOperatingLicense."ResultsareforasimilartypeswitchsuccessfullytestedbytheGeneralElectricCompany.Testconditionsweremorestringentthanthosecommitted.Insummary,testresultsindicatethatthemainsteamisolationvalvepositionswitcheswillperformtheirrequiredfunctionduringnormalandincidentconditions.Sincerely,eraldK.RdeVicePresident-EngineeringAttachment8285 IIe~~Pt~

MAINSTEAMISOLATIONVALVEPOSITIONSWITCHENVIRONMENTALTESTREPORT~SummarThisreportwaspreparedtodocumentthequalificationoftheNationalAcmeCompanylimitswitch.modelnumberSL-3MDP-DT.Limitswitchesofthisdesignareusedtomonitorthepositionofmainsteamisolationvalvestemsandtogeneratescramsignals.Theobjectiveofthesteamchambertestwastoqualifytheoperationofthesubjectlimitswitchesintheabnormalambientconditionsduringthefirst24hoursafteraLoss-of-CoolantAccident.Toqualify,thelimitswitchwasrequiredtooperatefor24hoursunderthecontrolledatmosphere.Twoswitchesweretestedforaddedconfidence.ThereareminordifferencesbetweenthetestswitchandtheinstalledswitchatNineMilePointUnit1.Thesedonotaltertheapplicabilityofthetestresults.(SeetheDiscussionSection.)Inaddition,thetestconditionsweremoreconservativethanthosecommitted.Atwenty-fourhourtestwasperformed;threehoursat103psigand340F,3hoursat75psigand320Fand18hoursat16psigand250F.Ascommittedatestat340Fand62psigwasrequired.Theaboveconservativetestingconditionswouldalsotendtonegateanyslightdifferencesbetweentheinstalledswitchandthetestedswitch.Ithasbeendemonstratedbythetestingdescribedhereinthattheswitcheswilloperateforatleast24hoursinthesteamatmosphereinwhichitwastested.SincethetestconditionsconservativelysimulateLoss-of-CoolantAccidentambientconditions,itisconcludedthatthelimitswitcheswilloperatenormallyundertheactualpost-Loss-of-CoolantAccidentconditionsforatleast24hours.Inaddition,thejunctionboxandthehookupwirewerealsofoundtoretaintheirintegrityandfunctionproperly.ProcedureTwolimitswitches'weretestedinaccordancewiththetestdescription,entitled"TestDescription,PositionSwitchforMainSteamIsolationValve,SteamEnvironment"(attachedasExhibit1).Briefly,thetestconsistedofthefollowing.Thelimitswitchestestassembly(includingthejunctionboxandhookupwire)wasplacedinasteamchamber.Steamwasgeneratedtoproduceanenvironmentofabout103psigpressureand340F.Theswitcheswereoperatedduringa3hourperiod.Theenvironmentwasthenchangedto75psigpressureand320F.Theswitcheswereagainoperatedduringthenext

18hours.Theactionsofthelimitswitchesweresignifiedbyonandoffcon-ditionsofthelightbulbsandtheactionofthesolenoidvalveconnectedtothelimitswitches.Uponremovalfromthetestchamber,thetestassemblywasdisassembledandinspected.DiscussionLimitswitchesofthemodeltestedareusedtomonitorthemainsteamisolationvalvepositionandtogeneratescramsignals.Thelimitswitchesperformtheirsafetyfunctionwithin5to10minutesaftertheLoss-of-CoolantAccident.Atestperiodof24hourswasselectedformarginofconfidence.TherearedifferencesbetweenthetestswitchandtheinstalledswitchatNineMilePointUnit1,TheNineMilePointswitchhasanepoxysealedconduitopeningfortheelectricalleadswhereastheswitchtesteddidnot.ThisdifferenceisexpectedtoimprovetheperformanceoftheNineMilePointswitch.TheNineMilePointswitchhasanoilimpregnatedbrassshaftbushinginsteadofthesolidbrassbushingonthetested.switch.Basedontheabove,theswitchesareessentiallythesameandtheresultsreceivedforthetestswitchareapplicabletotheoperationoftheinstalledswitchesatNine.MilePoint.ResultsAnevaluationofthedatareceivedindicatesthatthelimitswitchqualifiesfortheabnormalambientconditionsofthefirst24hoursafteraLoss-of-CoolantAccident.Thetestitselfproceededinaroutinemanner,andtheswitchesfunctionednormallyforthe24hourtestperiod.Visualinspectionofthetestassemblyrevealedpeelingofthepaintonthesurfacesofthejunctionbox,slightcharringofthelubricant,andbendingofthelongersidesofthejunctionbox(inwardforabout1/8ofaninch).Thecontactsoftheswitcheswerefoundintact,withnosignsofpittingorburning.'he.hookup-wireswerefoundingoodcondition.Therewasnodiscolorationoftheinsulation.Thejunctionboxwasfoundtohavemaintaineditsintegrity.Therewasnotraceofmoistureorcondensateinthejunctionbox.Thepeelingofpaints,andbendingofthejunctionboxdidnotinterferewiththeswitchoperation.Thetestpressureof103psigismuchhigherthanthepeakpressureexpected,soinrealitythejunctionboxwouldbendevenlessthan1/8ofaninch.Thecharredlubricantdidnotinterferewithswitchoperationduringthetest.Therefore,theswitcheswillprovidetheirdesignfunctionduringnormalandincidentconditions.

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EXHIBIT1TESTDESCRIPTIONPOSITIONSl(ITCHFORMAINSTEAMISOLATIONVALVESTEAMENVIRONMENTI.EuimentToBeTestedA.PositionSwitchManufacturer:Model:RatedCapacity:NationalAcmeMfg.Co.SL-3MDP-DT125volts,20ampsB.WiringSize:Type:16GaStrandedGeneralElectricVulkene-insulatedhookupwireA.Autoclavecapableof350FTemperatureand150psigpressure.B.Calrodtypeheatercontrolledbyanautotransformerandasafetyrelaytolimitmaximumtemperature.C.Temperatureisrecordedbasedonoutputfromathermocouplelocatedinthesteamregionoftheautoclave.Apressureindicatorisavailable.III.TestProcedureA.Thetwoswitchestobetestedaremountedwithaprcssure-operateddevicetoactuatetheswitches.Cablesfromtheswitchesarecontainedwithintheautoclaveandconnectedtowireswhichpenetratetheauto-clave.i%enthepressure-operateddeviceisenergized,theswitchisactuatedandasignalobservedoutsidetheautoclave.B.Theswitchesaremountedinsidetheautoclaveandwateraddedtoimmersetheheaters.Thetemperatureisraisedtoboilingandtheairpurgedfromtheautoclave,Thetemperatureisraisedfurthertothedesiredlevelandrecorded.Thepressureisobservedandcheckedagainstsaturatedsteampressureforthecorrespondingtemperature,

C.Conditionswithintheautoclaveareheldatorabovethefollowingconditionsforatleasttheperiodindicated:340F320F2SOF3hours3hours18hours'.Thetestswitchesareactuatedfromopentoclosedtoopenatthebeginning,theend,andatleastoneothertimeduringthetestperiodforeachtemperaturelevel.Thetestsignalisatleast120volts,4Svolt-amperesinrushand25volt-amperessteadystate.E.CriteriaforsuccessfulcompletionA.ThesignaldescribedinIII.D.aboveshallbeobservedeachtimetheswitchisactuated.

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