ASTM E834-2004 用冷凝管测定真空室气态环境的标准实施规程

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【英文标准名称】:StandardPracticeforDeterminingVacuumChamberGaseousEnvironmentUsingaColdFinger
【原文标准名称】:用冷凝管测定真空室气态环境的标准实施规程
【标准号】:ASTME834-2004
【标准状态】:现行
【国别】:
【发布日期】:2004
【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】:E21.05
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:真空的;航空航天运输;试验;气体;环境;手指;气体的;煤气;航天技术
【英文主题词】:coldfinger;contaminationmonitoring;residualgascompositions;vacuumchamber
【摘要】:Whenappliedinthecaseinwhichthereisnotestiteminthevacuumchamber(suchasduringbake-outoperations),thisproceduremaybeusedtoevaluatetheperformanceofthevacuumchamberinrelationtootherdatafromthesameorotherchambersgiventhatcriticalparameters(forexample,lengthofexposure,temperatureofthechamberandcoldfinger,anisotropy,andsoforth)canberelated.Theprocedurecanbeusedtoevaluatetheeffectsofmaterialsfoundintheresidueonitemsplacedinthevacuumchamber.Theprocedurecanbeusedtodescribetheeffectofapriortestontheresidualgaseswithinavacuumchamber.Byselectingthetimeatwhichthecoolantisintroducedintothecoldfinger,theenvironmentpresentduringaselectedportionofatestcanbecharacterized.Thiscanbeusedtodeterminetherelativeefficacyofcertainvacuumchamberproceduressuchasbake-out.Theproceduremaybeusedtodefinetheoutgassedproductsofatestitemthatcondenseonthecoldfinger.Theproceduremaybeusedindefiningtherelativecleanlinessofavacuumchamber.Inapplyingtheresultsoftheproceduretothevacuumchamberingeneral,considerationmustbegiventotheanisotropyofthemolecularfluxeswithinthechamber.Theprocedureissensitivetoboththepartialpressuresofthegasesthatformthecondensiblesandthetimeofexposureofthecoldfingeratcoolanttemperatures.Theprocedureissensitivetoanylossesofsamplethatmayoccurduringthevarioustransferoperationsandduringthatprocedurewhereinthesolventisevaporatedbyheatingitonasteambath.Note18212;Reactionsbetweensolventandcondensatecanoccurandwouldaffecttheanalysis.1.1Thispracticecoversatechniqueforcollectingsamplesofmaterialsthatarepartoftheresidualgasenvironmentofanevacuatedvacuumchamber.Thepracticeusesadevicedesignatedasa"coldfinger"thatisplacedwithintheenvironmenttobesampledandiscooledsothatconstituentsoftheenvironmentareretainedonthecold-fingersurface.1.2Thepracticecoversamethodforobtainingasamplefromthecoldfingeranddeterminingtheweightofthematerialremovedfromthecoldfinger.1.3Thepracticecontainsrecommendationsastowaysinwhichthesamplemaybeanalyzedtoidentifytheconstituentsthatcomprisethesample.1.4Bydeterminingthespeciesthatconstitutethesample,thepracticemaybeusedtoassistindefiningthesourceoftheconstituentsandwhetherthesampleisgenerallyrepresentativeofsamplessimilarlyobtainedfromthevacuumchamberitself.1.5Thispracticecoversalternativeapproachesandusagestowhichthepracticecanbeput.1.6Thedegreeofmolecularfluxanisotropysignificantlyaffectstheassurancewithwhichonecanattributecharacteristicsdeterminedbythisproceduretothevacuumchamberenvironmentingeneral.1.7Thetemperatureofthecoldfingersignificantlyaffectsthequantityandspeciesofmaterialscollected.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.Forspecificwarningstatements,seeSection.
【中国标准分类号】:J78
【国际标准分类号】:23_160
【页数】:5P.;A4
【正文语种】: