按照我国的形位公差标准,常见的位置公差有:平行度、垂直度、同轴度、对称度、位置度及圆跳等。在精密零件加工中,由于定位基准、机床夹具或加工方法的原因,零件加工表面与其他表面之间总会存在一定的相对位置误差。不同工序所产生的位置误差,又会在整个零件上互相累积,造成不能满足设计要求。因此,必须通过计算对加工过程中的位置公差予以控制和规定,从而达到满足设计要求的目的。 According to our standard form tolerance, common position tolerances are: parallelism, perpendicularity, concentricity, symmetry, position degree and circle jump. In the precision machining of parts, there is always a certain relative position error between the machined surface and other surfaces due to the positioning datum, machine tool fixture or machining method. Position error generated by different processes, will accumulate each other in the whole part, resulting in can not meet the design requirements. Therefore, it is necessary to control and stipulate the position tolerance in the process through calculation, so as to meet the design requirements.