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【英文标准名称】:StandardGuideforIn-ServiceAnnealingofLight-WaterModeratedNuclearReactorVessels
【原文标准名称】:轻水冷却核反应堆容器在运转中逐渐冷却的标准指南
【标准号】:ASTME509-2003(2008)
【标准状态】:现行
【国别】:美国
【发布日期】:2003
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E10.02
【标准类型】:(Guide)
【标准水平】:()
【中文主题词】:
【英文主题词】:fracturetoughness;irradiation;nuclearreactorvessels(light-watermoderated);radiationexposure;surveillance(ofnuclearreactorvessels);Annealing;Fracturetesting--nuclearreactors;Nuclearapplications/materials--steel;Nuclearreactorvessels
【摘要】:Reactorvesselsmadeofferriticsteelsaredesignedwiththeexpectationofprogressivechangesinmaterialpropertiesresultingfromin-serviceneutronexposure.Intheoperationoflight-water-coolednuclearpowerreactors,changesinpressure-temperature(Px2013;T)limitsaremadeperiodicallyduringservicelifetoaccountfortheeffectsofneutronradiationontheductile-to-brittletransitiontemperaturematerialproperties.Ifthedegreeofneutronembrittlementbecomeslarge,therestrictionsonoperationduringnormalheat-upandcooldownmaybecomesevere.Additionalconsiderationshouldbegiventopostulatedevents,suchaspressurizedthermalshock(PTS).Areductionintheuppershelftoughnessalsooccursfromneutronexposure,andthisdecreasemayreducethemarginofsafetyagainstductilefracture.Whenitappearsthatthesesituationscoulddevelop,certainalternativesareavailablethatreducetheproblemorpostponethetimeatwhichplantrestrictionsmustbeconsidered.Oneofthesealternativesistothermallyannealthereactorvesselbeltlineregion,thatis,toheatthebeltlineregiontoatemperaturesufficientlyabovethenormaloperatingtemperaturetorecoverasignificantportionoftheoriginalfracturetoughnessandothermaterialpropertiesthatwerelostasaresultofneutronembrittlement.Preparationandplanningforanin-serviceannealshouldbeginearlysothatpertinentinformationcanbeobtainedtoguidetheannealingoperation.Sufficienttimeshouldbeallocatedtoevaluatetheexpectedbenefitsinoperatinglifetobegainedbyannealing;toevaluatetheannealingmethodtobeemployed;toperformthenecessarysystemstudiesandstressevaluations;toevaluatetheexpectedannealingrecoveryandreembrittlementbehavior;todevelopandfunctionallytestsuchequipmentasmayberequiredtodothein-serviceannealing;and,totrainpersonneltoperformtheanneal.Selectionoftheannealingtemperaturerequiresabalanceofopposingconditions.Higherannealingtemperatures,andlongerannealingtimes,canproducegreaterrecoveryoffracturetoughnessandothermaterialpropertiesandtherebyincreasethepost-anneallifetime.Theannealingtemperaturealsocanhaveanimpactonthereembrittlementtrendaftertheanneal.Ontheotherhand,highertemperaturescancreateotherundesirablepropertyeffectssuchaspermanentcreepdeformationortemperembrittlement.Thesehighertemperaturesalsocancauseengineeringdifficulties,thatis,coreandcoolantremovalandstorage,localizedheatingeffects,etc.,inpreventingtheannealingoperationfromdistortingthevesselordamagingvesselsupports,primarycoolantpiping,adjacentconcrete,insulation,etc.SeeASMECodeCaseN-557forfurtherguidanceonannealingconditionsandthermal-stressevaluations(2).Whenareactorvesselapproachesastateofembrittlementsuchthatannealingisconsidered,themajorcriterionisthenumberofyearsofadditionalservicelifethatannealingofthevesselwillprovide.Twopiecesofinformationareneededtoanswerthequestion:thepost-annealadjustedRTNDTanduppershelfenergylevel,andtheirsubsequentchangesduringfutureirradiation.Furthermore,ifavesselisannealed,thesameinformationisneededasthebasisforestablishingpressure-temperaturelimitsfortheperiodimmediatelyfollowingtheannealanddemonstratingcompliancewithotherdesignrequirementsandthePTSscreeningcriteria.Theeffectsonuppershelftoughnesssimilarlymustbeaddressed.ThisguideprimarilyaddressesRTNDTchanges.HandlingoftheuppershelfispossibleusingasimilarapproachasindicatedinNRCRegulatoryGuide1.16.......
【中国标准分类号】:F69
【国际标准分类号】:27_120_10
【页数】:11P.;A4
【正文语种】:英语