液压支架用大铰接销轴加工余量分析

Analysis on machining allowance of large hinge pin for hydraulic support

依据GB/T 702-2008从理论上分析销轴保有加工余量,然后取3组试样进行了验证,结果显示:该试样粗加工余量不宜小于5 mm,精加工余量不宜小于2 mm,总加工余量不宜少于7 mm;为了消除表面氧化皮对热处理的影响,粗加工时应完全去除氧化皮;采购尺寸偏差、不圆度和弯曲度较小的原材料也可以减小加工余量;原材料出现明显弯曲情况时,可以在加工前增加原材料校直工序;对于非关键受力销轴,对热处理质量要求不高时,可简单粗车后即进行热处理。

According to GB / T 702-2008, the limit machining allowance of the pin is theoretically analyzed, and then three groups of samples are verified. The results show： the rough allowance of this sample should not be less than 5 ram, and the finishing allowance should not be less than 2 ram, the total allowance should not be less than 7 mm; in order to eliminate the intluenee of surface oxide on heat treatment, ox- ide should be completely removed in rough processing; purchase raw materials with small dimensional deviation and small out-of-roundness and small bending can also reduce the machining allowance; raw materials appear obvious bending, you can increase the straightening process before the machining; for non-key bearing pin, tire heat treatment quality requirements are not high, can make heat treatment al- ter simple rough turning.