基本信息
| 标准名称： | 三硫化二锑化学分析方法 重量法测定王水不溶物 |
| 中标分类： |
冶金 >>
金属化学分析方法 >>
重金属极其合金分析方法 |
| ICS分类： |
冶金 >>
金属材料试验 >>
金属材料化学分析
|
| 替代情况： | 原标准号GB/T 3255.4-1982;被YS/T 239.4-2010代替 |
| 发布日期： | |
| 实施日期： | 1997-01-01 |
| 首发日期： | |
| 作废日期： | 2011-03-01 |
| 出版日期： | |
| 页数： | 2页 |
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所属分类： 冶金 金属化学分析方法 重金属极其合金分析方法 冶金 金属材料试验 金属材料化学分析
【英文标准名称】:StandardTestMethodforMeasuringRollingFrictionCharacteristicsofaSphericalShapeonaFlatHorizontalPlane
【原文标准名称】:在平坦水平面上测量球形滚动摩擦特性的标准试验方法
【标准号】:ASTMG194-2008
【标准状态】:现行
【国别】:美国
【发布日期】:2008
【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】:(TestMethod)
【标准水平】:()
【中文主题词】:
【英文主题词】:balls;coefficientofrollingfriction;plane;rollingfriction;spheres
【摘要】:Rollingfrictionlikeslidingfrictiondependsuponmanyfactors.Itisasystemeffectthatinvolvesthenatureoftherollingsurfaceandthecounterface.Theslidingfrictionforce(F)isusuallyconsideredtobethesumofforcesarisingfromdeformationsofsurfacefeatures(Fs),fromattractiveforces(atomic,molecular,etc.)atcontactpoints(Fa)andforcefrominteractionoffilmsandparticulatesontherubbingsurfaces(Ff):Therollingfrictionforceincludestheseforcecontributionspluseffectsfromtherelativestiffnessofthecontactingsurfaces,thediameter(curvature)ofthesphericalshape(ball,orange,etc.)andotherfactors.Becausetherearesomanyfactorsinvolvedinarollingtribosystem,rollingresistancecanbestbequantifiedbyanactualtestofthesphereofinterestontheintendedcounterface,asinthistestmethod.Therearecountlessapplicationswhereitisimportanttoquantifytherollingcharacteristicsofaparticularsphericalshapeonaparticularsurface.Theinterlaboratorytestsconductedforthistestmethodwereperformedonhardenedsteelballslikethoseusedinballbearings.Thistestmethodcouldbeusedtoassesstheeffectofdifferentcounterfacesurfacesontherollingcharacteristicsofballsforballbearings.Conversely,itcouldbeusedasaqualitycontroltestonballs.Surfaceimperfections/defects/films,etc.ontheballscanaffecthowtheyroll:thedistancetraveledonacommoncounterface.5.3Industrialapplicationsofthistestmethodcanincludeassessingconveyingsurfacesforsphericalornearlyspecialparts:checkvalveballs,cabinetknobs,Christmasornaments,toiletfloats,etc.Manymedicaldevicesusespecialshapeswhererollingcharacteristicsareaconsideration.Similarly,manypharmaceuticalproducts(pills)aresphericalornearlysphericalinshape,andthistestmethodcanbeusedtoassessrollingcharacteristicsforconveyingorotherreasonssuchassize(mass)check.5.4Rollingfrictionofsphericalshapescanbeaconsiderationincountlesssports(soccer,golf,lacrosse,etc.)andgameapplications(billiards,bocce,toys,etc.).Thistestmethodcanbeusedtoranktherollingresistanceofdifferentballcompositions,masses,shapes,surfacetextures,design,stiffness,etc.Similarly,thetestmethodcanbeusedtoassesstheeaseofrollingofballsondifferentplayingorgamesurfaces.5.5Thistestmethodisveryapplicabletosphericalormostlysphericalfoodproducts.Forexample,itiscommontouserollingdistanceofapples,citrus,nuts,etc.toclassifythembysizeformarketing.Theyarerolleddownanangledsurfaceandtherollingdistancebecomesafunctionofsize(mass/diameter).Thistestmethodcanbeusedtoassessthesuitabilityofvariousrollingsurfaces(carpet,metal,wood,etc.)forsuitabilityinclassificationequipment.Itcouldalsobeusedforfoodconveyanceonspherical-shapedprocessedfoods(gumballs,hardcandy,meatballs,etc.)5.6Finally,thistestmethodcanbeavaluableteachingtoolforphysicsandtribologystudents.Theequipmentissimple,lowcostandstudentproof.Itcanbeusedtodemonstratetheconceptofrollingfrictionandthefactorsthataffectit.1.1Thistestmethodcoverstheuseofanangledlaunchramptoinitiaterollingofasphereornearlysphericalshapeonaflathorizontalsurfacetodeterminetherollingfrictioncharacteristicsofagivensphericalshapeonagivensurface.1.1.1Steelballsonasurfaceplatewereusedininterlaboratorytests(seeAppendixX1).Golfballsonagreen,soccerandlacrosseballsonplayingsurfaces,b......
【中国标准分类号】:J04
【国际标准分类号】:17_040_20
【页数】:9P.;A4
【正文语种】:英语