屋脊齿破岩生成岩屑特性研究

为了更加深入研究屋脊齿破岩机理,完善屋脊齿在生成岩屑方面的相关理论,采用试验与数值模拟相结合的方法,从屋脊齿破岩机理的角度,研究岩屑生成过程、切削参数(切削深度、后倾角)对岩屑质量分数的影响和岩屑粒径分布的规律。研究结果表明:屋脊齿破岩生成岩屑可分为屋脊齿楞脊结构接触岩石、楞脊结构吃入岩石内部造成预破碎、屋脊齿2个斜面及齿刃轮廓剪切岩石3个阶段,并且随着屋脊齿对岩石的周期性破坏,岩石内部裂纹扩展到岩石表面形成岩屑; 切削深度与岩屑粒径、大块岩屑质量分数占比呈正相关; 后倾角存在最优解,且最优解与由机械比功和屋脊齿侵入能力共同决定; 粒径分布符合Rosin-Rammler分布函数,且切削参数的变化不影响岩屑粒径分布规律,其相关系数均大于0.95。研究成果是对屋脊齿破岩机理的完善,为今后脊形金刚石钻头的优化设计提供理论参考。

Study on Cuttings Generated by Ridge Cutter

In order to further study the rock breaking mechanism of the ridge cutter, and to complete the theoretical research of the ridge cutter in generating cuttings, by using a combination of experiments and numerical simulations, from the perspective of the ridge cutter’s rock breaking mechanism, the law of cuttings generation process, the influence of working parameters(cutting depth, back dip angle)on the proportion of cuttings mass fraction, and the size of the cutting distribution law. The research results show that the ridge cutter rock fragmentation can be divided into three stages, the ridge cutter ridge structure contacts the rock, the ridge structure eats into the rock to cause pre-fragmentation, the ridge cutter two slopes, and the tooth edge profile shear the rock. With the periodic destruction of the rock by ridge cutter, the internal cracks in the rock spread to the surface of the rock to form cuttings. The cutting depth is positively correlated with the particle size of cuttings and the mass fraction of large cuttings. There is an optimal solution for the back dip angle, and the optimal solution is determined by the mechanical specific energy(MSE)and the intrusion ability of the ridge cutter. The particle size distribution conforms to the Rosin-Rammler distribution function, the change of cutting parameters does not affect the particle size distribution of the cuttings generated by the ridge cutter, and the correlation coefficients are all greater than 0.95. The research results are the perfection of the rock-breaking mechanism of the ridge cutter and provide a theoretical reference for the optimal design of the ridge diamond bit in the future.