1,尺寸size1000- 3000mm2,切削刀类型 cutter type81/2寸钻头牙掌，8村滚刀,江汉合金齿81/2” tricone bit cutter , 8” hob cutter , IADC code 517,537,637, kingdream teeth material steel YG163,连接螺纹Thread connectionPin*box (IF,REG , NC,FH )4,应用Application硬岩石扩孔桥桩地基工程，如硬页岩、石灰岩、砂岩、…