经验告诉我们,在加工直径为20—25毫米以及更大的孔时,用整体式搪刀是不合适的.因此必须采用能在杆内插入方形的或圆形断面搪刀的搪杆.苏联某铣床工厂,制造了一种用分度环调整搪孔直径的搪杆(如附图)当旋转分度环时,分度环则抵住搪刀的端部,使搪刀伸出到要求的尺寸,伸出尺寸由刻度盘上的读数读出。然后用螺钉 Experience has taught us that in the processing of holes with a diameter of 20-25 mm and larger it is not suitable to use a monolithic boring tool, so that it is necessary to use a boring bar which inserts a square or circular cross-section boring bar into the shaft. A milling machine factory, made a graduated ring diameter adjustment of the bored bore (as the figure) When the indexing ring rotation, the indexing ring is to withstand the end of the boring blade, the boring knife extended to the requirements The size of which is read out by the reading on the dial. Then use screws