ASME规范产品金属材料和焊件着色液体渗透检验

ASME规范产品金属材料和焊件着色液体渗透检验1．概述1．1本规程适用于ASME规范产品金属材料和焊件着色液体渗透检验。1．2本规程仅适用于探测材料或焊件表面开口类缺陷。1．3本规程在执行之前，须演示至AI满意。2．人员2.1从事液体渗透检验的人员必须是根据南京定色钛业有限公司NDE人员培训、考试、资格认证实施细则(资料号：QCD-011)进行考试和资格任命的合格人员。3.渗透材料3.1渗透材料包括检验过程中使用的所有渗透剂、溶剂或清洗剂、显像剂等。3.2液体渗透探伤材料，必须是指定的和推荐的，见表3.2。检验使用的材料必须是同一类型的。不允许用不同类型的或不同制造厂的渗透材料混合使用表3.23.3当检验奥氏体不锈钢或钛材时，必须根据ASME规范第Ⅴ卷T-641(b)中的程序，对所有材料分别分析氯和氟的含量。残留氯和氟总含量不得超过残留物重量的1%，必须有制造厂相应的合格证。3.4当检查镍基合金时，必须按照ASME规范第Ⅴ卷T-641(a)中的程序，对所有材料分别分析硫含量。硫含量不得超过残留物重量的1%。必须有制造厂相应的合格证。4.检验程序4.1检验程序流程图见图4.1图4.14.2表面制备所有渗透检验前，被检工件表面及其附近至少为1英寸(25.4mm)的区域内都应干燥清洗干净，不得有任何脏物、纤维屑、氧化皮、焊剂、油和其它外来物。必要时，应对表面进行打磨或机加工。4.3预清洗4.3.1在施加渗透剂之前，被检区域及其附近至少为1英寸(25.4mm)的区域内均需用清洁剂进行清洗。4.3.2清洗后，通过适当的方法(自然挥发或人工通风)，对被检表面进行干燥；最少干燥的时间以保证在施加渗透剂之前清洁剂已完全挥发为界。4.4施加渗透剂4.4.1可以用浸渍、涂刷或喷涂等任一合适的方法，在被检工件NJBSTCo.,Ltd.QCD-015Rev.:0Page:5of8Title:PROCEDUREFORLIQUIDPENETRANTEXAMINATIONofworkpiecestobeexaminedbyanysuitablemeanssuchasdipping,brushingorspraying.4.4.2Thetemperatureofthepenetrantandthesurfacetobeexaminedshallnotbebelow500F(100C)norabove1250F(520C)throughouttheexaminationperiod.Whenitisnotpracticaltoconductaliquidpenetrantexaminationwithinabovetemperaturerange,theexaminationprocedureattheproposedlowerorhighertemperaturerangeshallbequalifiedusingaquenchcrackedaluminumblockaccordingtoASMECodeSectionV,T-653.4.4.3Penetrationtimeiscritical.TheminimumdwelltimeisshowninTable4.4.3.Forsuitabletemperature,theareabeingexaminedshallremainwettedbythepenetrantforthedwelltime.Table4.4.3Recommendedminimumdwelltimes4.5ExcessPenetrantRemovalExcesssolventremovablepenetrantshallberemovedbywipingwithaclothorabsorbentpaper.Theremainingtracesshallberemovedbylightlywipingthesurfacewithaclothorabsorbentpapermoistenedwithsolvent.Toavoidoverremoving,flushingthesurfacewithsolventshallbeprohibited.4.6DeveloperApplication4.6.1Thedevelopershallbeappliedassoonaspossibleafterexcesspenetrantremovalanddryingsurface.Thesurfacemaybedriedbynormalevaporationbeforethedeveloperisapplied.Thedryingtimeshallbewithin5to20min.4.6.2Thedevelopershallbeappliedbyspraying.Auniformthincoatingshallbeprovidedandthecoatingthicknessshallbesuitable.4.6.3Priortoapplyingwetdevelopertothesurface,thedevelopermustbethoroughlyagitated.4.6.4Dippingorfloodingthepartwithnon-aqueousdeveloperisprohibited,sinceitwilldissolvethepenetrantinthediscontinuitiesthroughitssolventaction.4.7Interpretation4.7.1Developingtimeforfinalinterpretationbegins表面施加渗透剂。4.4.2在整个检验期间，渗透剂和被检表面的温度不得低于500F(100C)，不得高于1250F(520C)。当在上述温度范围内不能满足时，则按照ASME规范第V卷T-653，对提议采用的温度范围，使用有淬火裂纹的铝试块进行验证。4.4.3严格控制渗透时间，最小滞留时间见表4.4.3。适当的温度条件下，在滞留时间内，被检区域必须用渗透剂保持潮湿。表4.4.3推荐的最少滞留时间4.5多余渗透剂的清除多余渗透剂必须用布或吸纸擦去，剩下的痕迹必须用蘸有溶剂的布或纸在表面轻轻地擦去。为了防止清洗过分，禁止用溶剂清洗表面。4.6施加显像剂4.6.1多余的渗透剂被清除且工件干燥后，必须尽快地施加显像剂。显像剂施加之前，工件表面可以自然挥发干燥，干燥时间必须在5-20分钟以内。4.6.2施加显像剂必须采用喷涂法，薄且均匀，涂层厚度适中。4.6.3在施加湿型显像剂至工件表面之前，显像剂必须充分搅拌。4.6.4禁用非水湿显像剂浸渍或灌洗工件，因非水湿显像剂会通过溶解作用将缺陷中的渗透剂溶解掉。4.7判断4.7.1最终判断显像时间应从施加NJBSTCo.,Ltd.QCD-015Rev.:0Page:6of8Title:PROCEDUREFORLIQUIDPENETRANTEXAMINATIONassoonasawetdevelopercoatingisdry.Theminimumdevelopingtimeshallbe7min.4.7.2Finalinterpretationshallbemadewithin7to60minaftertherequirementsofPara.4.7.1aresatisfied.4.7.3Thedevelopingtracecanbeexaminedeitherbynaturallightorartificiallight.Aminumumlightintensityof50fc(500Lx)isrequiredtoensureadequatesensitivityduringtheexaminationandevaluationofindications.4.7.4Thesurfaceshallbedividedintoseveralpartstobeexaminedifthesurfaceissolargethattheexaminationcannotbefinishedwithinthegiventime.Thedevelopingconditioncanbeobservedeitherbyeyesorbymeansofamagnifier.4.8Post-cleaningThepenetrantmaterialsshallbeclearlyremovedawayfrompartsafterexamination.Thepostcleaningmustbeperformedifremainingpenetrantmaterialscanresultincorrosionbythecombinationwithothermaterialsduringtheoperation.Thesuitablecleaningprocessshallbeadoptedforpostcleaningsuchasflushingwithwater,mechanicalcleaning,solventsoaking,etc.Thedevelopershallbecleanedassoonaspossibleafterexaminationifthepartrequeststhepostcleaningsoastoavoiditcondensedonthepart.5.EvaluationofIndications5.1Broadareasofpigmentationwhichcouldmaskindicationsofdiscontinuitiesareunacceptableandsuchareasshallbecleanedandreexamined.5.2Anindicationistheevidenceofamechanicalimperfection.Onlyindicationswithmajordimensionsgreaterthan1/16in(1.6mm)shallbeconsideredrelevant.5.3Linearindicationsarethoseindicationsinwhichthelengthismorethanthreetimesthewidth.Roundedindicationsareindicationswhicharecircularorellipsoidalwiththelengthlessthanthreetimesthewidth.5.4Anyquestionableordoubtfulindicationsshallbereexaminedtodeterminewhetherornottheyarerelevant.Surfaceconditioningmayproceedbeforethereexamination.5.5Theindicationofadiscontinuitymaybelargerthanthediscontinuitythatcausesit;however,thesizeoftheindicationisthebasisofacceptanceorrejection.6.AcceptanceStandardsThefollowingrelevantindicationsareunacceptable:a.anycracksorrelevantlinearindications;b.relevantroundedindicationsgreaterthan3/16in.(4.8mm);c.fourormorerelevantroundedindicationsinalineseparatedby1/16in.(1.6mm)orless(edgetoedge);干显像剂后或从湿显像剂涂层干燥后立即起算，不得少于7分钟。4.7.2在满足4.7.1要求后，最终判断必须在