基准转换在生产应用中的分析

Analysis of Datum Conversion in Production Application

以槽形零件为例,分析了槽加工中对称度和尺寸公差不易控制的加工难点,并针对加工完成后出现槽尺寸变大的问题,提出在加工槽时把基准孔转换到零件外表面上的实体平面的加工方法。同时提出在尺寸链计算中,将含有零尺寸对称度位置公差换算为对称偏差计入尺寸链的方法,并建议在尺寸链反计算分配公差时采用不完全互换法更符合实际尺寸的分布规律。

Taking a slot part as example,we analyze the difficulties in the processing of slot.To the problem that the size of the slot is changed after the processing is finished,the processing method of converting the datum hole into the solid plane is proposed in production.And the method of converting zero dimension symmetry degree to the dimension chain is presented.The paper also suggests that the distribution of tolerance with incomplete interchangeable method in the inverse calculation of dimension chain conforms to the law of actual size.