套铣钻头在钻塞时 ,钻头旋转 ,使铣头吃入灰塞边缘后形成灰柱 ,单向铣牙做圆周运动切削灰柱 ,实现钻塞 ,如有落物铣牙旋转落物拔入筒内 ,不影响钻塞。文中介绍了该套铣钻头的结构特点、工作原理、主要技术参数、研制该工具的关键技术及应用情况 Set milling bit in the drill, the drill bit rotation, the milling head to eat after the edge of the gray plug to form an ash column, one-way milling circular motion cutting ash column, to achieve drilling, Tube, does not affect the drill. This paper introduces the structural features, working principle, main technical parameters, the key technology and application of the tool