一、迴转钻进时岩石硬度概念迴转钻进时确定岩石可钻性的最主要因素一般认为是岩石的硬度和研磨性。其理论与实践依据是：第一、现用迴转钻进碎岩工具以硬质合金、金刚石作为钻头齿刃，钻进过程依赖压入—剪切、压裂—压碎的作用；细粒孕镶金刚石钻头以磨削破碎岩石。如果把磨粒放大，也和前者的破碎岩石作用相仿。十分明显，一般较坚硬的岩石总是比较软的岩石难以钻进，也就是钻进速度较低。 First, the concept of rotary drilling rock hardness Rotary drilling to determine the most important factor in the drillability of the rock is generally considered the hardness of the rock and grinding. The theory and practice are based on the following aspects: First, the current rotary drilling crushing tools to carbide, diamond as the drill edge, drilling process depends on press-shear, fracturing-crushing effect; fine Impregnated with diamond bits to grind crushed rock. If you enlarge the abrasive, but also the role of the former broken rock is similar. Obviously, rocks that are generally harder are often harder to drill than softer rocks, which means they are drilled slower.