日本三菱公司研制出在钻头中心处无切削刃的钻头,获得惊人的切削性能,以往的钻头有横刃,中心处参予切削,切削过程不理想。经改进后的新型钻头无横刃,可提高孔加工的效率和精度。这种新型钻头具有如下特点: ①适用于钢材切削;②轴向力是过去钻头的30～50%; Japan’s Mitsubishi Corporation has developed a drill without a cutting edge at the center of the drill bit, resulting in an amazing cutting performance. In the past, the drill had a chisel edge, and the center was involved in cutting. The cutting process was not satisfactory. The improved new drill without chisel edge, can improve the efficiency and accuracy of hole processing. The new drill has the following characteristics: ① for steel cutting; ② axial force is 30 to 50% of the past bit;