SAE AS4208 Fitting End, Bulkhead, External Thread, Beam Seal, Design Standard

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Product Code:SAE AS4208
Title:Fitting End, Bulkhead, External Thread, Beam Seal, Design Standard
Issuing Committee:G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
Scope:No scope available.
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【英文标准名称】:Specificationfortungstenelectrodesforinertgasshieldedarcweldingandforplasmacuttingandwelding
【原文标准名称】:惰性气体保护电弧焊和等离子切割与焊接用钨电极规范
【标准号】:BSEN26848-1991
【标准状态】:作废
【国别】:英国
【发布日期】:1991-06-28
【实施或试行日期】:1991-06-28
【发布单位】:英国标准学会(BSI)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:长度;缺陷与故障;电弧焊接设备;掺杂剂;钨;包装;直径;作标记;金属弧焊;电极;名称与符号;热切割设备;电弧切割;直流电流;焊接设备;直线度测量;化学成分;交流电流;电焊条;色码;气体保护焊
【英文主题词】:
【摘要】:
【中国标准分类号】:J64
【国际标准分类号】:25_160_20
【页数】:12P;A4
【正文语种】:英语


【英文标准名称】:StandardTestMethodforConcentrationLimitsofFlammabilityofChemicals(VaporsandGases)
【原文标准名称】:化合物(蒸气和气体)易燃性浓度限值的标准试验方法
【标准号】:ASTME681-2004
【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】:E27.04
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:化合物;浓缩;最大值;试验;材料;防火安全;易燃性;统计学
【英文主题词】:flammability;chemicals;vapors;gases
【摘要】:TheLFLandUFLofgasesandvaporsdefinetherangeofflammableconcentrationsinair.Limitsofflammabilitymaybeusedtodetermineguidelinesforthesafehandlingofvolatilechemicals.Theyareusedparticularlyinassessingventilationrequirementsforthehandlingofgasesandvapors.NFPA69providesguidanceforthepracticaluseofflammabilitylimitdata,includingtheappropriatesafetymarginstouse.Note28212;Forhydrocarbons,thebreakpointbetweennonflammabilityandflammabilityoccursoveranarrowconcentrationrangeatthelowerflammabilitylimit,butthebreakpointislessdistinctattheupperlimit.Formaterialsfoundtobenon-reproducibleper13.1.1thatarelikelytohavelargequenchingdistancesandmaybedifficulttoignite,suchasammoniaandcertainhalogenatedhydrocarbon,thelowerandupperlimitsofthesematerialsmaybothbelessdistinct.Thatis,awiderrangeexistsbetweenflammableandnonflammableconcentrations(seeAnnexA1).Note38212;ThismethodmeasurestheLFLandUFLforupward(andpartiallyoutward)flamepropagation.thelimitsfordownwardflamepropagationarenarrower.1.1Thistestmethodcoversthedeterminationofthelowerandupperconcentrationlimitsofflammabilityofchemicalshavingsufficientvaporpressuretoformflammablemixturesinairatatmosphericpressureatthetesttemperature.Thistestmethodmaybeusedtodeterminetheselimitsinthepresenceofinertdilutiongases.Nooxidantstrongerthanairshouldbeused.Note18212;Thelowerflammabilitylimitandupperflammabilitylimitarealsoreferredtoasthelowerexplosivelimit(LEL)andtheupperexplosivelimit(UEL),respectively.1.2Thistestmethodisbasedonelectricalignitionandvisualobservationsofflamepropagation.Usersmayexperienceproblemsiftheflamesaredifficulttoobserve(forexample,irregularpropagationorinsufficientluminescenceinthevisiblespectrum),ifthetestmaterialrequireslargeignitionenergy,orifthematerialhaslargequenchingdistances.1.3providesamodifiedtestmethodformaterials(suchascertainamines,halogenatedmaterials,andthelike)withlargequenchingdistanceswhichmaybedifficulttoignite.1.4Inothersituationswherestrongignitionsources(suchasdirectflameignition)isconsideredcredible,theuseofatestmethodemployinghigherenergyignitionsourceinasufficientlylargepressurechamber(analogous,forexample,tothemethodsinTestMethodE2079formeasuringlimitingoxygenconcentration)maybemoreappropriate.Inthiscase,expertadvicemaybenecessary.1.5Theflammabilitylimitsdependonthetesttemperatureandpressure.Thistestmethodislimitedtoaninitialpressureofthelocalambientorless,withapracticallowerpressurelimitofapproximately13kPa(100mmHg).Themaximumpracticaloperatingtemperatureofthisequipmentisapproximately150176;C(302176;F).1.6ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareprovidedforinformationonly.1.7Thistestmethodshouldbeusedtomeasureanddescribethepropertiesofmaterials,products,orassembliesinresponsetoheatandflameundercontrolledlaboratoryconditionsandshouldnotbeusedtodescribeorappraisethefirehazardorfireriskofmaterials,products,orassembliesunderactualfireconditions.However,resultsofthistestmethodmaybeusedaselementsofafireriskassessmentthattakesintoaccountallofthefactorspertinenttoanassessmentofthefirehazardofaparticularenduse.1.8Thisstandardmayinvolvehazardousmaterials,operations,andequipment.Thisstandarddoesnotpurporttoaddress......
【中国标准分类号】:G04
【国际标准分类号】:13_220_40;71_060_01;71_080_01
【页数】:12P.;A4
【正文语种】: