UsedinUSNRC-RDTstandards
StandardPracticefor
UltrasonicExaminationofSteelForgings1ThisstandardisissuedunderthefixeddesignationA388/A388M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.
1.Scope*
1.1Thispractice2coverstheexaminationproceduresforthecontact,pulse-echoultrasonicexaminationofsteelforgingsbythestraightandangle-beamtechniques.ThestraightbeamtechniquesincludeutilizationoftheDGS(DistanceGain-Size)method.SeeAppendixX3.
1.2Thispracticeistobeusedwhenevertheinquiry,contract,order,orspecificationstatesthatforgingsaretobesubjecttoultrasonicexaminationinaccordancewithPracticeA388/A388M.
1.3ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedseparatelyasstandard.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnon-conformancewiththestandard.
1.4Thisspecificationandtheapplicablematerialspecifica-tionsareexpressedinbothinch-poundunitsandSIunits.However,unlesstheorderspecifiestheapplicable“M”speci-ficationdesignation[SIunits],thematerialshallbefurnishedtoinch-poundunits.
1.5Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.
2.ReferencedDocuments2.1ASTMStandards:3A469/A469MSpecificationforVacuum-TreatedSteelForgingsforGeneratorRotors
A745/A745MPracticeforUltrasonicExaminationofAus-teniticSteelForgings
ThispracticeisunderthejurisdictionofASTMCommitteeA01onSteel,StainlessSteelandRelatedAlloysandisthedirectresponsibilityofSubcommitteeA01.06onSteelForgingsandBillets.
CurrenteditionapprovedMay1,2009.PublishedMay2009.Originallyapprovedin1955.Lastpreviouseditionapprovedin2008asA388/A388M–08.2ForASMEBoilerandPressureVesselCodeapplicationsseerelatedSpecifi-cationSA-388/SA-388MinSectionIIofthatCode.3ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,orcontactASTMCustomerServiceatservice@astm.org.ForAnnualBookofASTMStandardsvolumeinformation,refertothestandard’sDocumentSummarypageontheASTMwebsite.
1E317PracticeforEvaluatingPerformanceCharacteristicsofUltrasonicPulse-EchoTestingInstrumentsandSystemswithouttheUseofElectronicMeasurementInstrumentsE428PracticeforFabricationandControlofMetal,OtherthanAluminum,ReferenceBlocksUsedinUltrasonicTesting
E1065GuideforEvaluatingCharacteristicsofUltrasonicSearchUnits
2.2ANSIStandard:B46.1SurfaceTexture42.3OtherDocument:
RecommendedPracticeforNondestructivePersonnelQuali-ficationandCertificationSNT-TC-1A,(1988orlater)53.Terminology3.1Definitions:
3.1.1indicationlevels(clusters),n—fiveormoreindica-tionsinavolumerepresentinga2-in.[50-mm]orsmallercubeintheforging.
3.1.2individualindications,n—singleindicationsshowingadecreaseinamplitudeasthesearchunitismovedinanydirectionfromthepositionofmaximumamplitudeandwhicharetoosmalltobeconsideredtravelingorplanar.
3.1.3planarindications,n—indicationsshallbeconsideredcontinuousoveraplaneiftheyhaveamajoraxisgreaterthan1in.[25mm]ortwicethemajordimensionofthetransducer,whicheverisgreater,anddonottravel.
3.1.4travelingindications,n—inductionswhoseleadingedgemovesadistanceequivalentto1in.[25mm]ormoreofmetaldepthwithmovementofthetransduceroverthesurfaceoftheforging.
4.SignificanceandUse
4.1Thispracticeshallbeusedwhenultrasonicinspectionisrequiredbytheorderorspecificationforinspectionpurposeswheretheacceptanceoftheforgingisbasedonlimitationsofthenumber,amplitude,orlocationofdiscontinuities,oracombinationthereof,whichgiverisetoultrasonicindications.
AvailablefromAmericanNationalStandardsInstitute(ANSI),25W.43rdSt.,4thFloor,NewYork,NY10036.5AvailablefromtheAmericanSocietyforNondestructiveTesting,1711Arlin-gateLn.,P.O.Box28518,Columbus,OH43228–0518.
4*ASummaryofChangessectionappearsattheendofthisstandard.
Copyright©ASTMInternational,100BarrHarborDrive,POBoxC700,WestConshohocken,PA19428-2959,UnitedStates.
1
A388/A388M–09
4.2Theultrasonicqualitylevelshallbeclearlystatedasorderrequirements.
5.OrderingInformation
5.1Whenthispracticeistobeappliedtoaninquiry,contract,ororder,thepurchasershallsostateandshallalsofurnishthefollowinginformation:
5.1.1Designationnumber(includingyeardate),
5.1.2Methodofestablishingthesensitivityinaccordancewith9.2.2and9.3.3(Vee-orrectangular-notch),
5.1.2.1Thediameterandtestmetaldistanceoftheflat-bottomholeandthematerialofthereferenceblockinaccordancewith9.2.2.2,
5.1.3Qualitylevelfortheentireforgingorportionsthereofinaccordancewith12.3,and
5.1.4Anyoptionsinaccordancewith1.4,6.4,6.5,7.1,8.1,8.2,9.1.11,10.1,and10.2.
6.Apparatus
6.1Anultrasonic,pulsed,reflectiontypeofinstrumentshallbeusedforthisexamination.Thesystemshallhaveamini-mumcapabilityforexaminingatfrequenciesfrom1to5MHz.Onexaminingausteniticstainlessforgingsthesystemshallhavethecapabilitiesforexaminingatfrequenciesdownto0.4MHz.
6.1.1Theultrasonicinstrumentshallprovidelinearpresen-tation(within5%)foratleast75%ofthescreenheight(sweeplinetotopofscreen).The5%linearityreferredtoisdescriptiveofthescreenpresentationofamplitude.InstrumentlinearityshallbeverifiedinaccordancewiththeintentofPracticeE317.AnysetofblocksprocessedinaccordancewithPracticeE317orE428maybeusedtoestablishthespecified65%instrumentlinearity.
6.1.2Theelectronicapparatusshallcontainanattenuator(accurateoveritsusefulrangeto610%(+1dB)oftheamplituderatio)whichwillallowmeasurementofindicationsbeyondthelinearrangeoftheinstrument.
6.2SearchUnits,havingatransducerwithamaximumactiveareaof1in.2[650mm2]with3⁄4in.[20mm]minimumto11⁄8in.[30mm]maximumdimensionsshallbeusedforstraight-beamscanning(see9.2);andsearchunitswith1⁄2in.[13mm]minimumto1in.[25mm]maximumdimensionsshallbeusedforangle-beamscanning(see9.3).
6.2.1Transducersshallbeutilizedattheirratedfrequencies.6.2.2Othersearchunitsmaybeusedforevaluatingandpinpointingindications.
6.3Couplants,havinggoodwettingcharacteristicssuchasSAENo.20orNo.30motoroil,glycerin,pineoil,orwatershallbeused.Couplantsmaynotbecomparabletooneanotherandthesamecouplantshallbeusedforcalibrationandexamination.
6.4ReferenceBlocks,containingflat-bottomholesmaybeusedforcalibrationofequipmentinaccordancewith6.1.1andmaybeusedtoestablishrecordinglevelsforstraight-beamexaminationwhensospecifiedbytheorderorcontract.
6.5DGSScales,matchedtotheultrasonictestunitandtransducertobeutilized,maybeusedtoestablishrecordinglevelsforstraightbeamexamination,whensospecifiedbytheorderorcontract.TheDGSscalerangemustbeselectedto
2
includethefullthicknesscross-sectionoftheforgingtobeexamined.AnexampleofaDGSoverlayisfoundinAppendixX3.
6.5.1AsanalternativetousingDGSoverlays,anultrasonicinstrumenthavingintegraldecibelgainorattenuatorcontrolsincombinationwithaspecificallypairedtransducerandDGSdiagrammaybeusedtoevaluateultrasonicindications.7.PersonnelRequirements
7.1PersonnelperformingtheultrasonicexaminationstothispracticeshallbequalifiedandcertifiedinaccordancewithawrittenprocedureconformingtoRecommendedPracticeNo.SNT-TC-1A(1988orlater)oranothernationalstandardthatisacceptabletoboththepurchaserandthesupplier.
8.PreparationofForgingforUltrasonicExamination8.1Unlessotherwisespecifiedintheorderorcontract,theforgingshallbemachinedtoprovidecylindricalsurfacesforradialexaminationinthecaseofroundforgings;theendsoftheforgingsshallbemachinedperpendiculartotheaxisoftheforgingfortheaxialexamination.Facesofdiskandrectangularforgingsshallbemachinedflatandparalleltooneanother.8.2Thesurfaceroughnessofexteriorfinishesshallnotexceed250µin.[6µm]unlessotherwiseshownontheforgingdrawingorstatedintheorderorthecontract.
8.3Thesurfacesoftheforgingtobeexaminedshallbefreeofextraneousmaterialsuchasloosescale,paint,dirt,andsoforth.
9.Procedure9.1General:
9.1.1Asfaraspracticable,subjecttheentirevolumeoftheforgingtoultrasonicexamination.Becauseofradiiatchangeofsectionsandotherlocalconfigurations,itmaybeimpossibletoexaminesomesectionsofaforging.
9.1.2Performtheultrasonicexaminationafterheattreat-mentformechanicalproperties(exclusiveofstress-relieftreatments)butpriortodrillingholes,cuttingkeyways,tapers,grooves,ormachiningsectionstocontour.Iftheconfigurationoftheforgingrequiredforthetreatmentformechanicalpropertiesprohibitsasubsequentcompleteexaminationoftheforging,itshallbepermissibletoexaminepriortotreatmentformechanicalproperties.Insuchcases,reexaminetheforgingultrasonicallyascompletelyaspossibleafterheattreatment.9.1.3Toensurecompletecoverageoftheforgingvolume,indexthesearchunitwithatleast15%overlapwitheachpass.9.1.4Formanualscanning,donotexceedascanningrateof6in./s[150mm/s].
9.1.5Forautomatedscanning,adjustscanningspeedorinstrumentrepetitionrate,orboth,topermitdetectionofthesmallestdiscontinuitiesreferencedinthespecificationandtoallowtherecordingorsignalingdevicetofunction.Atnotimeshallthescanningspeedexceedthespeedatwhichanacceptablecalibrationwasmade.
9.1.6Ifpossible,scanallsectionsofforgingsintwoperpendiculardirections.
9.1.7Scandiskforgingsusingastraightbeamtechniquefromatleastoneflatfaceandradiallyfromthecircumference,wheneverpracticable.
A388/A388M–09
9.1.8Scancylindricalsectionsandhollowforgingsradially9.2.2.4ChoosetheappropriateDGSscaleforthecross-usingastraight-beamtechnique.Whenpracticable,alsoexam-sectionalthicknessoftheforgingtobeexamined.Inserttheinetheforgingintheaxialdirection.
overlayovertheCRTscreen,ensuringtheDGSscalebaseline9.1.9Inaddition,examinehollowforgingsbyangle-beamcoincideswiththesweeplineoftheCRTscreen.Placethetechniquefromtheoutsidediametersurfaceasrequiredinprobeontheforging,adjustthegaintomakethefirstback-wall9.3.1.
echoappearclearlyonCRTscreen.UsingtheDelayand9.1.10InrecheckingorreevaluationbymanufacturerorSweepcontrol,shiftthescreenpatternsothattheleadingedgepurchaser,usecomparableequipment,searchunits,frequency,oftheinitialpulseisonzerooftheDGSscaleandtheandcouplant.
back-wallechoisontheDGSscalevaluecorrespondingtothe9.1.11Forgingsmaybeexaminedeitherstationaryorwhilethicknessoftheforging.Adjustthegainsotheforgingrotatinginalatheoronrollers.Ifnotspecifiedbytheback-wallechomatchestheheightoftheDGSreferenceslopepurchaser,eithermethodmaybeusedatthemanufacturer’swithin61Db.Onceadjusted,increasethegainbytheDboption.
shownontheDGSscaleforthereferenceslope.Instrumentis9.2Straight-BeamExamination:
nowcalibratedandflawsizesthatcanbereliablydetectedcan9.2.1Forstraight-beamexaminationuseanominal21⁄4-bedirectlyreadfromtheCRTscreen.TheseflawsizesaretheMHzsearchunitwheneverpracticable;however,1MHzistheequivalentflatbottomreflectorthatcanbeusedasareferencepreferredfrequencyforcoarsegrainedausteniticmaterialsandpoint.
longtestingdistances.InmanyinstancesonexaminingcoarseNOTE3—Theabovecanbeutilizedonallsolidforgings.Cylindricalgrainedausteniticmaterialsitmaybenecessarytouseahollowforgings,anddrilledorboredforgingsmustbecorrectedtofrequencyof0.4MHz.Otherfrequenciesmaybeusedifcompensateforattenuationduetothecentralhole(seeAppendixX4).
desirableforbetterresolution,penetrability,ordetectabilityofflaws.
9.2.3Recalibration—Anychangeinthesearchunit,cou-9.2.2Establishtheinstrumentsensitivitybyeithertheplant,instrumentsetting,orscanningspeedfromthatusedforreflection,reference-blocktechnique,orDGSmethod(seecalibrationshallrequirerecalibration.PerformacalibrationAppendixX3foranexplanationoftheDGSmethod).
checkatleastonceevery8hshift.Whenalossof15%or9.2.2.1Back-ReflectionTechnique(Back-ReflectionCali-greaterinthegainlevelisindicated,reestablishtherequiredbrationApplicabletoForgingswithParallelEntryandBackcalibrationandreexamineallofthematerialexaminedintheSurfaces)—Withtheattenuatorsetatanappropriatelevel,forprecedingcalibrationperiod.Whenanincreaseof15%orexample5to1or14dB,adjusttheinstrumentcontrolstogreaterinthegainlevelisindicated,reevaluateallrecordedobtainabackreflectionapproximately75%ofthefull-screenindications.
heightfromtheoppositesideoftheforging.Scantheforging9.2.4Duringtheexaminationoftheforging,monitortheatthemaximumamplificationsettingoftheattenuator(attenu-backreflectionforanysignificantreductioninamplitude.atorsetat1to1).CarryouttheevaluationofdiscontinuitiesReductioninback-reflectionamplitudemayindicatenotonlywiththegaincontrolsetatthereferencelevel.Recalibrationisthepresenceofadiscontinuitybutalsopoorcouplingoftherequiredforsignificantchangesinsectionthicknessordiam-searchunitwiththesurfaceoftheforging,nonparallelback-eter.
reflectionsurface,orlocalvariationsofattenuationintheforging.Recheckanyareascausinglossofbackreflection.NOTE1—Highsensitivitylevelsarenotusuallyemployedwhenin-9.3Angle-BeamExamination—RingsandHollowForgings:spectingausteniticsteelforgingsduetoattendanthighlevelof“noise”or9.3.1Performtheexaminationfromthecircumferenceof“hash”causedbycoarsegrainstructure.
ringsandhollowforgingsthathaveanaxiallengthgreaterthan9.2.2.2Reference-BlockCalibration—Thetestsurface2in.[50mm]andanoutsidetoinsidediameterratiooflessroughnessonthecalibrationstandardshallbecomparableto,than2.0to1.
butnobetterthan,theitemtobeexamined.Adjustthe9.3.2Usea1MHz,45°angle-beamsearchunitunlessinstrumentcontrolstoobtaintherequiredsignalamplitudethickness,OD/IDratio,orothergeometricconfigurationresultsfromtheflat-bottomholeinthespecifiedreferenceblock.infailuretoachievecalibration.OtherfrequenciesmaybeusedUtilizetheattenuatorinordertosetuponamplitudeslargerifdesirableforbetterresolution,penetrability,ordetectabilitythantheverticallinearityoftheinstrument.Inthosecases,offlaws.Forangle-beaminspectionofhollowforgingsuptoremovetheattenuationpriortoscanningtheforging.
2.0to1ratio,providethetransducerwithawedgeorshoethatwillresultinthebeammodeandanglerequiredbythesizeandNOTE2—Whenflat-surfacedreferenceblockcalibrationisspecified,shapeofthecrosssectionunderexamination.
adjusttheamplitudeofindicationfromthereferenceblockorblockstocompensateforexaminationsurfacecurvature(anexampleisgivenin9.3.3Calibratetheinstrumentfortheangle-beamexamina-AppendixX1).
tiontoobtainanindicationamplitudeofapproximately75%full-screenheightfromarectangularora60°V-notchoninside9.2.2.3DGSCalibration—Priortouse,verifythattheDGSdiameter(ID)intheaxialdirectionandparalleltotheaxisofoverlaymatchesthetransducersizeandfrequency.Accuracytheforging.Aseparatecalibrationstandardmaybeused;oftheoverlaycanbeverifiedbyreferenceblocksandhowever,itshallhavethesamenominalcomposition,heatproceduresoutlinedinPracticeE317.Overlaysaretobetreatment,andthicknessastheforgingitrepresents.Thetestserializedtomatchtheultrasonictransducerandpulseechosurfacefinishonthecalibrationstandardshallbecomparabletestingsystemthattheyaretobeutilizedwith.
butnobetterthantheitemtobeexamined.Whereagroupof
3
---`,,`,`,,`,,`-`-`````,,``,`,`,```,`,,,```,,`--A388/A388M–09
identicalforgingsismade,oneoftheseforgingsmaybeusedastheseparatecalibrationstandard.CuttheIDnotchdepthto3%maximumofthethicknessor1⁄4in.[6mm],whicheverissmaller,anditslengthapproximately1in.[25mm].Thicknessisdefinedasthethicknessoftheforgingtobeexaminedatthetimeofexamination.Atthesameinstrumentsetting,obtainareflectionfromasimilarODnotch.DrawalinethroughthepeaksofthefirstreflectionsobtainedfromtheIDandODnotches.Thisshallbetheamplitudereferenceline.Itispreferabletohavethenotchesinexcessmetalortestmetalwhenpossible.WhentheODnotchcannotbedetectedwhenexaminingtheODsurface,performtheexaminationwhenpracticable(someID’smaybetoosmalltopermitexamina-tion),asindicatedabovefromboththeODandIDsurfaces.UtilizetheIDnotchwheninspectingfromtheOD,andtheODnotchwheninspectingfromtheID.Curvewedgesorshoesmaybeusedwhennecessaryandpracticable.
9.3.4Performtheexaminationbyscanningovertheentiresurfaceareacircumferentiallyinboththeclockwiseandcounter-clockwisedirectionsfromtheODsurface.Examineforgings,whichcannotbeexaminedaxiallyusingastraightbeam,inbothaxialdirectionswithanangle-beamsearchunit.Foraxialscanning,userectangularor60°V-notchesontheIDandODforthecalibration.Thesenotchesshallbeperpendicu-lartotheaxisoftheforgingandthesamedimensionsastheaxialnotch.
10.Recording
10.1Straight-BeamExamination—Recordthefollowingin-dicationsasinformationforthepurchaser.Theserecordableindicationsdonotconstitutearejectableconditionunlessnegotiatedassuchinthepurchaseorderorcontract.10.1.1Forindividualindications,report:
10.1.1.1Intheback-reflectiontechnique,individualindica-tionsequaltoorexceeding10%ofanominalbackreflectionfromanadjacentareafreefromindications,and
10.1.1.2Inthereference-blockorDGStechnique,indica-tionsequaltoorexceeding100%ofthereferenceamplitude.10.1.2Forindicationsthatareplanar,traveling,orclustered,determinethelocationoftheedgesandthemajorandminoraxesusingthehalf-amplitude(6dBdrop)techniqueandreport:10.1.2.1Thevariationindepthorplanararea,orboth,oftravelingindications,
10.1.2.2Thelengthofmajorandminoraxesofplanarindications,and
10.1.2.3Thevolumeoccupiedbyindicationlevelsandtheamplituderange.
10.2Angle-BeamExamination—Recorddiscontinuityindi-cationsequaltoorexceeding50%oftheindicationfromthereferenceline.Whenanamplitudereferencelinecannotbegenerated,recorddiscontinuityindicationsequaltoorexceed-ing50%ofthereferencenotch.Theserecordableindicationsdonotconstitutearejectableconditionunlessnegotiatedassuchinthepurchaseorder.
10.3Reportreductioninbackreflectionexceeding50%oftheoriginalmeasuredinincrementsof10%.
10.4Whenrecording,correctionsmustbemadeforbeamdivergenceattheestimatedflawdepth(SeeGuideE1065).10.5Reportindicationamplitudesinincrementsof10%.
4
11.Report
11.1Reportthefollowinginformation:
11.1.1Allrecordableindications(seeSection10);
11.1.2Forthepurposeofreportingthelocationsofrecord-ableindications,asketchshallbepreparedshowingthephysicaloutlineoftheforgingincludingdimensionsofallareasnotinspectedduetogeometricconfiguration,thepur-chaser’sdrawingnumber,thepurchaser’sordernumber,andthemanufacturer’sserialnumber,andtheaxial,radial,andcircumferentialdistributionofrecordableultrasonicindica-tions;
11.1.3Thedesignation(includingyeardate)towhichtheexaminationwasperformedaswellasthefrequencyused,methodofsettingsensitivity,typeofinstrument,surfacefinish,couplant,andsearchunitemployed;and
11.1.4Theinspector’snameoridentityanddatetheexami-nationwasperformed.
12.QualityLevels
12.1Thispracticeisintendedforapplicationtoforgings,withawidevarietyofsizes,shapes,compositions,meltingprocesses,andapplications.Itis,therefore,impracticabletospecifyanultrasonicqualitylevelwhichwouldbeuniversallyapplicabletosuchadiversityofproducts.Ultrasonicaccep-tanceorrejectioncriteriaforindividualforgingsshouldbebasedonarealisticappraisalofservicerequirementsandthequalitythatcannormallybeobtainedintheproductionoftheparticulartypeforging.
12.2Austeniticstainlesssteelforgingsaremoredifficulttopenetrateultrasonicallythansimilarcarbonorlow-alloysteelforgings.Thedegreeofattenuationnormallyincreaseswithsectionsize;andthenoiselevel,generallyorinisolatedareas,maybecometoogreattopermitdetectionofdiscreteindica-tions.Inmostinstances,thisattenuationresultsfrominherentcoarsegrainedmicrostructureoftheseausteniticalloys.Forthesereasons,themethodsandstandardsemployedforultra-sonicallyexaminingcarbonandlow-alloysteelforgingsmaynotbeapplicabletoausteniticsteelforgings.Ingeneral,onlystraightbeaminspectingusingaback-reflectionreferencestandardisused.However,utilizationofPracticeA745/A745Mforausteniticsteelforgingscanbeconsideredifflatbottomholereferencestandardsoranglebeamexaminationofthesegradesarerequired.
12.3Acceptancequalitylevelsshallbeestablishedbetweenpurchaserandmanufactureronthebasisofoneormoreofthefollowingcriteria.
12.3.1Straight-BeamExamination:
12.3.1.1Noindicationslargerthansomepercentageofthereferencebackreflection.
12.3.1.2Noindicationsequaltoorlargerthantheindicationreceivedformtheflat-bottomholeinaspecificreferenceblockorblocks.
12.3.1.3Noareasshowinglossofbackreflectionlargerthansomepercentageofthereferencebackreflection.
12.3.1.4Noindicationsper12.3.1.1or12.3.1.2coupledwithsomelossofresultantbackreflectionper12.3.1.3.
12.3.1.5Noindicationsexceedingthereferencelevelspeci-fiedintheDGSmethod
A388/A388M–09
12.3.2Angle-BeamExamination—Noindicationsexceed-ingastatedpercentageofthereflectionfromareferencenotchoroftheamplitudereferenceline.
12.4Intelligentapplicationofultrasonicqualitylevelsin-volvesanunderstandingoftheeffectsofmanyparametersonexaminationresults.
13.Keywords
13.1anglebeamexamination;back-reflection;DGS;reference-block;straightbeamexamination;ultrasonic
SUPPLEMENTARYREQUIREMENTS
Thefollowingsupplementaryrequirementsshallapplyonlywhenspecifiedbythepurchaserintheinquiry,contract,ororder.Detailsshallbeagreeduponbythemanufacturerandthepurchaser.
S1.ReportingCriteria
S1.1Referenceblockcalibrationshallbeperformedusingatleastthreeholes,spacedtoapproximateminimum,mean,andmaximumthicknessastested,andshallbeusedtogenerateadistanceamplitudecorrection(DAC)curve.Thefollowingholesizesapply:
1.1⁄16in.[1.5mm]flatbottomholes(FBH)forthicknesseslessthan1.5in.[40mm]
2.1⁄8in.[3mm]FBHforthicknessesof1.5-6in.[40-150mm]inclusive
3.1⁄4in.[6mm]FBHforthicknessesover6in.[150mm]
S1.2Reportingcriteriainclude:
1.2.
AllindicationsexceedingtheDACcurve
Twoormoreindicationsseparatedby1⁄2in.[12mm]orless
APPENDIXES
(NonmandatoryInformation)
X1.TYPICALTUNINGLEVELCOMPENSATIONFORTHEEFFECTSOFFORGINGCURVATURE
X1.1Thecurve(Fig.X1.1)wasdeterminedforthefollow-ingtestconditions:
Material
InstrumentSearchunitFrequency
Referenceblock
Reflectionareaofrefer-encecurveSurfacefinish
--`,,```,,,`,```,`,`,``,,`````-`-`,,`,,`,`,,`---nickel-molybdenum-vanadiumalloysteel(SpecificationA469/A469M,Class4)TypeURReflectoscope
11⁄8-in.[30-mm]diameterquartz21⁄4MHz
ASTMNo.3-0600(aluminum)
0.010in.2[6.5mm2]innickel-molybdenum-vana-diumalloysteel
250µin.[6µm],max,roughness
X1.2Toutilizecurve,adjustreflectoscopesensitivitytoobtainindicatedultrasonicresponseonASTMNo.3-0600referenceblockforeachdiameterasshown.Aresponseof1in.[25mm]sweep-to-peakisusedforflatsurfaces.Useattenuatortoobtaindesiredamplitude,butdotestingat1to1setting.
FIG.X1.1TypicalCompensationCurveforEffectsofForging
Curvature
5
A388/A388M–09
X2.INDICATIONAMPLITUDECOMPENSATIONFORTESTDISTANCEVARIATIONS
X2.1Thecurve(Fig.X2.1)hasbeendeterminedforthefollowingtestconditions:
Material
nickel-molybdenum-vanadiumalloysteel(SpecificationA469/A469M,Class4)InstrumentTypeURReflectoscope
Searchunit11⁄8-in.[30-mm]diameterquartzFrequency21⁄4MHzCouplant
No.20oil
Referenceblock
ASTMNo.3-0600(aluminum)
Reflectionareaofrefer-0.010in.2[65mm2]innickel-molybdenum-vana-encecurvediumalloysteel
Surfacefinish
250µin.max,roughness
X2.2Toutilizecurve,establishamplitudefromASTMreferenceblocktocoincidewithvaluesfromAppendixX1.
FIG.X2.1TypicalDistance-AmplitudeCorrectionCurve
X3.BACKGROUNDINFORMATIONONTHEDGSMETHODS
FIG.X3.1ExampleofDGSOverlay
6
---`,,`,`,,`,,`-`-`````,,``,`,`,```,`,,,```,,`--A388/A388M–09
X3.1TheoverlayinFig.X3.1wasdesignedfora2.0MHz,1in.[25mm]diameterprobeandamaximumtestdistanceof39.4in.[1000mm].Inordertousethisoverlay,thesweeptimebasemustbeaccuratelycalibratedandalignedwiththeoverlaybeingused.ThebackreflectionisthenadjustedtoeithertheRE+10dBlineortheRE+20dBline,basedonthethicknessbeingtested;additionalgain(10or20dB)isaddedas
designatedbythelinebeingused.TheRE+20linecoversarangetoapproximately15.7in.[400mm]andtheRE+10linefrom15.7to39.4in.[400to1000mm].Atthiscalibrationlevel,theflawsizeisreaddirectlyfromthescreen.Flawsizesfrom0.078to1in.[2to25mm]canbereaddirectlyfromtheoverlay.
X4.COMPENSATIONFORCENTERHOLEATTENUATIONONCYLINDRICALBOREDORHOLLOWFORGINGS
UTILIZINGTHEDGSMETHOD
X4.1Theholeinacylindricalboredforgingcausessoundscatter.Inthesecases,acorrectionisrequiredwhichdependsonthewallthicknessandborediameter.
X4.1.1DeterminethecorrectionvalueindBfromtheNomogram(Fig.X4.1).Withthegain-dBcontrol,proceedasdescribedin9.2.2.4reducingtheflawdetectorgainbythecorrectionvaluedetermined.
NOTE—MetricunitsarepresentedinthisfiguretobeconsistentwithDGSscalespresentlyavailable.ConversiontoEnglishunitswouldalsobeacceptable.
FIG.X4.1TheInfluenceofaCentralBoreontheBackwallEchoAmplitudeofCylindricalorPlaneParallelForgings
--`,,```,,,`,```,`,`,``,,`````-`-`,,`,,`,`,,`---7
A388/A388M–09
SUMMARYOFCHANGES
CommitteeA01hasidentifiedthelocationofselectedchangestothisstandardsincethelastissue(A388/A388M–08)thatmayimpacttheuseofthisstandard.(ApprovedMay1,2009.)
(1)Added6.5.1.
CommitteeA01hasidentifiedthelocationofselectedchangestothisstandardsincethelastissue(A388/A388M–07)thatmayimpacttheuseofthisstandard.(ApprovedNov.1,2008.)
(1)Droppedthetermheavyfromthetitleandbodyofthe(2)AddedSignificanceandUse(Section4).
standard.
ASTMInternationaltakesnopositionrespectingthevalidityofanypatentrightsassertedinconnectionwithanyitemmentionedinthisstandard.Usersofthisstandardareexpresslyadvisedthatdeterminationofthevalidityofanysuchpatentrights,andtheriskofinfringementofsuchrights,areentirelytheirownresponsibility.
Thisstandardissubjecttorevisionatanytimebytheresponsibletechnicalcommitteeandmustbereviewedeveryfiveyearsandifnotrevised,eitherreapprovedorwithdrawn.YourcommentsareinvitedeitherforrevisionofthisstandardorforadditionalstandardsandshouldbeaddressedtoASTMInternationalHeadquarters.Yourcommentswillreceivecarefulconsiderationatameetingoftheresponsibletechnicalcommittee,whichyoumayattend.IfyoufeelthatyourcommentshavenotreceivedafairhearingyoushouldmakeyourviewsknowntotheASTMCommitteeonStandards,attheaddressshownbelow.
ThisstandardiscopyrightedbyASTMInternational,100BarrHarborDrive,POBoxC700,WestConshohocken,PA19428-2959,UnitedStates.Individualreprints(singleormultiplecopies)ofthisstandardmaybeobtainedbycontactingASTMattheaboveaddressorat610-832-9585(phone),610-832-9555(fax),orservice@astm.org(e-mail);orthroughtheASTMwebsite(www.astm.org).
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