在大批量生产中,过去,为加工阶梯孔常常采用高速钢整体阶梯锪钻(如上之左图所示)。这种刀具均为专用刀具,不仅制造费用高,并且以后重磨费用也较高。现今,随着可转位刀片的推广,采用可转位刀片结构的阶梯锪钻日益增多。实践表明,这种刀具 In mass production, in the past, high-speed steel integral ladders were often used for machining stepped holes (as shown on the left). These knives are special tools, not only high cost of manufacture, and later re-grinding costs are higher. Nowadays, with the promotion of indexable inserts, the number of step countersinking using indexable insert structures has been increasing. Practice shows that this tool