本文所介绍的对称排屑槽麻花钻(图1)和不对称排屑槽麻花钻(图2)是西安石油学院孔加工课题组的两项专利。两种钻头都是用来钻削深孔的,前者可以有横刃,也可以无横刃,后者没有横刃。钻削轴向力小;容屑空间大;一般可以钻削(5～20)d_0(d_0为钻头直径)的深孔,一次钻通,中途不需退钻排屑,有四条棱带,导向良好,排屑顺畅,冷却液可通过冷却液输送槽进入切削刃部,冷却效果好,钻头经久耐用;钻孔质量良好。现将这两种钻头的结构特点及刃形介绍如下: Symmetric chip-cut twist drill (Figure 1) and asymmetric chip-cut twist drill (Figure 2) presented in this paper are two patents of the hole processing group of Xi’an Petroleum Institute. Both drill bits are used to drill deep holes. The former can have either chisel edge or chisel edge, while the latter has no chisel edge. Drilling axial force is small; chip space is large; generally can drill (5 ~ 20) d_0 (d_0 for the drill diameter) of the deep hole, a drilling, midway without drilling chip removal, with four strips, guide Good, chip evacuation, coolant through the coolant tank into the cutting edge, the cooling effect is good, the drill durable; good drilling quality. The structural characteristics of these two kinds of drill bit and now introduced as follows: