钻头式的强力镗刀是我厂青年工李思忠根据上海锅炉厂著名车工彭大生所创造的强力内孔镗刀改进的。这种镗刀的结构如图1。刀杆的形状很象钻头,是用45号钢做成,刀头用硬质合金,加工钢件时用 T_5K_(10),加工铸铁件用BK_6。刀头的几何角度:前角γ=25°,后角α(制造时)=0°、α(加工时)=3～5°, Drill-type powerful boring knife is our young workers Li Si-zhong based on the Shanghai Boiler Works Peng Dasheng car workers to create a strong hole bore boring knife to improve. This boring cutter structure shown in Figure 1. The shape of the arbor is very much like a bit, made of 45 # steel, with cemented carbide for the tip, T_5K_ (10) for machining steel, and BK_6 for cast iron. The geometric angle of the cutting head: γ = 25 ° for the rake angle, α (for the manufacture) = 0 ° for the relief angle, α = 3 to 5 ° for the machining,