尺寸公差与表面粗糙度.ppt

,Newwords:,LocatingAccuracySealingInterchangeabilityPistonfinish,工件定位精度，精确度密封，绝缘交替性活塞抛光磨光,Newexpressions,DimensionaltolerancesSurfaceroughnessProductioncostEconomicmanufacturingProducibilitystandpointShaftbearingBearingsurfaceSurfacefinish,尺寸公差表面粗糙度生产成本经济生产可生产的观点轴承承压面，支撑面表面加工/抛光,Sentence-analysis:,1.Becauseofthehighlycompetitivenatureofmostmanufacturingbusiness,thequestionoffindingwaystoreducecostiseverpresent.由于大多数制造业高度竞争的天性，找到降低成本的方法是永恒的问题。,Sentence-analysis:,2.Designingforfunction,interchangeability,quality,andeconomyrequiresacarefulstudyoftolerances,surfacefinishes,processes,materialsandequipment.功能、互换性、质量和经济性的设计都要求对公差、表面光洁度、工艺、材料和装备进行仔细研究。,Sentence-analysis:,3.Tolerancesonfinishanddimensionsplayanimportantroleinthefinalachievementorabsenceofpracticalproductiondesign.光洁度和尺寸公差在最终效果（成品）或者没有实际加工的设计中起重要作用。,Sentence-analysis:,4.Detailsofallpartsshouldbesurveyedcarefullytoassurenotonlyinexpensiveprocessingbutalsorapid,easyassemblyandmaintenance.Itmustberememberedthateachproductionmethodhasawell-establishedlevelofprecisionwhichcanbemaintainedincontinuousproductionwithoutexceedingnormalbasiccost.所有零件的细节都应该被仔细调查以确保工艺不仅简单快捷、容易安装，而且维修方便。这就必须记住每个加工方法都有一个已建立的适当的精度等级以维持连续加工而不超出正常的基本成本。,Sentence-analysis:,5.Withoutneedingtoknowhowtooperateaparticularmachinetoattainthedesireddegreeofsurfaceroughness,therearecertainaspectsofallmachiningmethodswhichshouldbeunderstoodbythedesignengineer.设计工程师无需知道怎样操作具体的机器来获得期望的表面粗糙度，但是应该理解每一种机械加工方法的诸多特定方面。,Sentence-analysis:,Knowledgeofsuchfactsasdegreeofallroughnessobtainedbyanyoperation,andtheeconomicsofattainingasmoothersurfacewitheachoperation,willaidthedesignengineerindecidingjustwhichsurfaceroughnesstospecify.每种操作所能获得的表面粗糙度及其成本等方面的知识有助于设计工程师确定所需的表面粗糙