我厂去年十月份生产的QY8型汽车起重机试车后解体检查,发现几只外齿圈滚道面上有大小不同的点状、片状、条状剥落现象,见图1。为分析产生剥落原因,对齿圈主要尺寸、热处理及工作条件进行了检查。外形尺寸和淬 I plant in October last year, the production of QY8 truck crane after the disintegration test test found that there are a few only a few outer ring raceway surface of the point size, flake, strip spalling phenomenon, shown in Figure 1. In order to analyze the causes of spalling, the main dimensions of ring gear, heat treatment and working conditions were examined. Dimensions and quenching