阶梯式导向钻头是一种新型钻头,能对多种不同材料进行钻孔加工,也能作精加工。在钻削和扩孔时,能保持较好的几何精度和光洁度。其结构和特点如下(图1): 1.具有导向部分,形成直径为d和d_1的阶梯式二层钻头。钻孔时,d钻头起定心、导向、切削作用,d_1担负主要切削作用,以改善切削条件,减轻轴向负荷,消除钻削振动。 Stepped pilot bits are a new type of drill bit that drills and cuts many different materials as well as finishing. In drilling and reaming, to maintain good geometric accuracy and finish. Its structure and characteristics are as follows (Figure 1): 1. With the guide part, the formation of the diameter d and d_1 stepped two drill. Drilling, d bit centering, guiding, cutting, d_1 bear the main cutting action to improve the cutting conditions, reduce the axial load, to eliminate drilling vibration.