机械加工中,对于有精度要求的孔,通常都是采用钻模来加工。近年来国外采用了一种新的孔加工工艺——按冲窝钻孔。这种方法的实质是,在毛坯上预先冲窝,然后,根据冲窝的位置钻孔。这种新工艺的优点是: 一、由于有较规矩的冲窝定位,钻头对心性好,从而避免了进刀时钻尖在毛坯表面晃动带来的位置误差。实践证明,孔的位置精度可提高3～5倍。二、由于钻头伸出量短,排屑空间大,散热好,故 Machining, for precision requirements of the hole, are usually used to drill. In recent years abroad adopted a new hole processing technology - according to punching holes. The essence of this method is to pre-bury the blank and then drill holes according to the position of the pocket. The advantages of this new process are: First, due to the more regular positioning of the dimples, the drill has good concentricity, thereby avoiding the position error caused by the slippage of the drill point on the rough surface when the knife is fed. Practice has proved that the hole position accuracy can be increased by 3 to 5 times. Second, due to the short drill bit, chip evacuation space, heat dissipation, so