钳工加工中,常有这样的阶梯孔如图1所示。按常规的加工方法:1)用直径d_1的麻花钻钻孔,钻L_3深;2)用直径d_2的麻花钻扩孔,深度小于L_2;3)用d_2的平底钻锪平至L_2;4)D孔的加工同工序2)、3)。这样工序多,质量差。如果加工零件数量多,效率很低,为此,我们制作了如图3所示的成 Fitter processing, there are often such ladder hole shown in Figure 1. According to the conventional processing methods: 1) Drilling L_3 deep with a drilled drill of diameter d_1; 2) Reaming using a twist drill of diameter d_2 with depth less than L_2; 3) Flat- D hole processing the same process 2), 3). This process more, poor quality. If the processing of a large number of parts, the efficiency is very low, for which we have produced as shown in Figure 3 into