【摘要】 运用PDC钻头几何学理论和分析方法,对影响岩石可钻性测定的关键因素之一——可钻性微钻头的结构合理性进行了研究,结果表明标准微钻头存在PDC齿的侧圆柱面与岩石试样的井底表面相干涉的问题。研究了微钻头的侧转角、后倾角和厚度对齿-岩干涉的影响规律,在此基础上,进行了微钻头结构的改进,得到了能避免干涉现象的PDC微钻头结构方案。更多还原

【Abstract】 Using the geometric theory and analysis method of PDC bits,it is proved in this paper that the cylindrical surface of the cutters of the standard micro bits used for rock drillability test will interfere with the bottom-hole rock surface,which will significantly affect the accuracy of rock drillability test and the decision on rock drillability grades. Study has been made on the effects of back rake angle,side rake angle,and thickness of the cutters on the interference phenomenon. And improvements on the structural parameters of the micro bit have been proposed.更多还原