尺寸公差与表面粗糙度

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,Dimensional tolerances and surface roughness,New words:,Locating,Accuracy,Sealing,Interchangeability,Piston,finish,工件定位,精度，精确度,密封，绝缘,交替性,活塞,抛光磨光,New expressions,Dimensional tolerances,Surface roughness,Production cost,Economic manufacturing,Producibility standpoint,Shaft bearing,Bearing surface,Surface finish,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.Because of the highly competitive nature of most manufacturing business,the question of finding ways to reduce cost is ever present.,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.Designing for function,interchangeability,quality,and economy requires a careful study of tolerances,surface finishes,processes,materials and equipment.,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.Tolerances on finish and dimensions play an important role in the final achievement or absence of practical production design.,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.,Details of all parts should be surveyed carefully to assure not only inexpensive processing but also rapid,easy assembly and maintenance.It must be remembered that each production method has a well-established level of precision which can be maintained in continuous production without exceeding normal basic cost.,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.Without needing to know how to operate a particular machine to attain the desired degree of surface roughness,there are certain aspects of all machining methods which should be understood by the design engineer.,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:,Knowledge of such facts as degree of all roughness obtained by any operation,and the economics of attaining a smoother surface with each operation,will aid the design engineer in deciding just which surface roughness to specify.,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度。,Thoughts,1.What is the secret in the film?,2.Do you agree with the secret?Why?(no less than 80 words),