孔、轴不等公差条件下的统计分组装配技术

分组适配率是分组装配中应关注的一个重要指标.对孔、轴公差等级不等条件下的公差带及分组调整提出实现方法,并讨论此种情形下的分组适配率预测及统计分组装配的公差及统计公差设计,这对提高装配精度和降低整个装配批生产过程的生产成本具有重要意义.过程能力指数Gp及偏移参数k对形成孔、轴配合尺寸的过程质量指标及分组适配率均有重要影响.利用统计公差实现统计分组装配技术,可以保证孔、轴公差等级不等条件下分组装配的预期适配率和配合精度.

Statistical selective assembly technology based on unequal tolerances of holes and shafts

The matchable degree is an important index of the process for selective assembly and should be considered in selective assembly.The calculation and realization method for adjusting the tolerance zone and intervals of each group is presented under the unequal tolerance degree of the mating lot of holes and shafts,and the predicting matchable degree,designing for tolerance and statistical tolerance are discussed in details,which has the realistic significance for improving assembling accuracy and reducing production cost of whole assembly process.The process capacity index Cp and the shift parameter k have important influence to the quality indices of the process that forms the mating sizes,specially to the matchable degree of selective assembly to holes and shafts.The statistical selective assembly can be realized via statistical tolerancing,thus,the designated matchable degree and fit precision can be assured under the unequal tolerance degree of the mating lot of holes and shafts.