ASTM C 495-1999 轻质隔热混凝土抗压强度的标准试验方法

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【英文标准名称】:StandardPracticeforConductingFrictionTestsofPistonRingandCylinderLinerMaterialsUnderLubricatedConditions
【原文标准名称】:在润滑条件下进行活塞环和缸衬材料摩擦试验的标准实施规程
【标准号】:ASTMG181-2004(2009)
【标准状态】:现行
【国别】:美国
【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】:G02.50
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:
【英文主题词】:cylinderliner;dieseloil;friction;liquidlubricant;pistonring;Cylinderlinermaterials;Frictiontests;Lubricatedmaterials/testing;Pistonrings
【摘要】:Theefficiencyandfueleconomyofsparkignitionanddieselenginesisaffectedinparttothefrictionbetweenmovingparts.Althoughnoreliable,insitufrictionmeasurementsexistforfiredinternalcombustionengines,ithasbeenestimatedthatatleasthalfofthefrictionlossesinsuchenginesareduetothoseattheringandlinerinterface.Thispracticeinvolvestheuseofareciprocatingslidingarrangementtosimulatethetypeofoscillatingcontactthatoccursbetweenapistonringanditsmatingcylinderboresurfacenearthetop-dead-centerpositioninthecylinderwheremostseveresurfacecontactconditionsoccur.Therearemanytypesofenginesandengineoperatingenvironments;therefore,toallowtheusertheflexibilitytotailorthistesttoconditionsrepresentativeofvariousengines,apracticeisconsideredmoreappropriatethanastandardtestmethodinwhichspecifictestparametersareprescribed.Variablesthatcanbeadjustedinthisprocedureinclude:normalforce,speedofoscillation,strokelength,durationoftesting,temperatureoftesting,methodofspecimensurfacepreparation,andthematerialsandlubricantstobeevaluated.Guidanceisprovidedhereontheset-upofthetest,themannerofspecimenfixturingandalignment,theselectionofalubricanttosimulateconditionedoilcharacteristics(foradieselengine),andthemeanstorun-intheringspecimenstominimizevariabilityintestresults.Engineoilspendsthemajorityofitsoperatinglifetimeinastatethatisrepresentativeofuse-conditionedoil.Thatis,freshoilischangedbyexposuretotheheat,chemicalenvironment,andconfinementinlubricatedcontact.Itages,changingviscosity,atomicweight,solidscontent,acidity,andchemistry.Conductingpistonringandcylinderlinermaterialevaluationsinfresh,non-conditionedoilisthereforeunrealisticformaterialscreening.Butadditive-depleted,usedoilcanresultinhighwearandcorrosiveattackofengineparts.Thecurrenttestisintendedforusewithlubricantsthatsimulatetribologicalbehaviorafterin-serviceoilconditioning,butprecedingthepointofsevereenginedamage.1.1Thispracticecoversproceduresforconductinglaboratorybench-scalefrictiontestsofmaterials,coatings,andsurfacetreatmentsintendedforuseinpistonringsandcylinderlinersindieselorspark-ignitionengines.Thegoalofthisprocedureistoprovideameansforpreliminary,cost-effectivescreeningorevaluationofcandidateringandlinermaterials.Areciprocatingslidingarrangementisusedtosimulatethecontactthatoccursbetweenapistonringanditsmatinglinernearthetop-dead-centerpositioninthecylinderwhereliquidlubricationisleasteffective,andmostwearisknowntooccur.Specialattentionispaidtospecimenalignment,running-in,andlubricantcondition.1.2Thispracticedoesnotpurporttosimulateallaspectsofafiredenginex2019;soperatingenvironment,butisintendedtoserveasameansforpreliminaryscreeningforassessingthefrictionalcharacteristicsofcandidatepistonringandlinermaterialcombinationsinthepresenceoffluidsthatbehaveasuse-conditionedengineoils.Therefore,itisbeyondthescopeofthispracticetodescribehowonemightestablishcorrelationsbetweenthedescribedtestresultsandthefrictionalcharacteristicsofringsandcylinderborematerialsforspecificenginedesignsoroperatingconditions.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapp......
【中国标准分类号】:J92
【国际标准分类号】:27_020
【页数】:9P.;A4
【正文语种】:英语

标准名称：	视镜 ⅠPg16 Dg100装配图
中标分类：	化工 >> 化工机械与设备 >> 化工机械与设备零部件
ICS分类：	化工技术 >> 化工设备
替代情况：	原标准号HGJ 501.8-1986
发布日期：
实施日期：	1992-01-01
首发日期：
作废日期：
出版日期：
页数：	4页

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