推土机终传动外壳体大孔径加工同轴度超差问题研究

Research on out-of-tolerance coaxiality of wide-aperture in bulldozer shell body during machining process

推土机终传动外壳体外壳体结构复杂、外廓尺寸大,刚性差、加工时容易变形,导致外壳体同轴度、垂直度超差。通过改善外壳体加工路线,增加辅助支撑点,减小了外壳体变形,提高了零件形位公差;同时对于基准孔宽度较小、被测量孔与基准孔距离较大的外壳体,提出了采用测量公共轴线的方法评价其同轴度,这样更符合生产实际情况。

The shell body has complicated structure and huge outline dimensions, it is easy to deform during the machining process,t hen lead to the out-of-tolerance coaxiality and squareness.I n this paper,t he shell body deformation was decreased, and geometric tolerance was increased by improving machining process route, and adding auxiliary bearing point. Meanwhile, a method to evaluate coaxiality by measuring common axis was presented aimed the problem thai the shell body has small datum hole, and distance between measured hole and datum hole is huge. This method is much more in line with actual production situation.