Rock cutting performance and wear characteristics of undercutting disc cutter: Based on experiment and DEM

Abstract

The undercutting disc cutter used to break the hard rock bears a huge load and severe wear during rock fragmentation; however, the wear mechanism and law of the cutter are still unclear. The wear mechanism of the undercutting disc cutter was revealed by comparing and analyzing the three-dimensional topography of the cutter before and after the experiments. Based on the DEM, the numerical model of rock cutting using an undercutting disc cutter was established and the influence of factors such as structural and working parameters on the wear behavior of the cutter was studied. The results indicate that under the large contact force, the hard particles of rock are inset into the cutter tip and the material was spalled, resulting in the local pits; the furrows on the cutter face are not continuous and less deep because of the contact between the cutter face and the bottom rock free-face is discontinuous. The wear of the cutter is positively related to the cutting depth and tip width, and negatively to the cutting angle. The circular tip has better wear resistance than the flat tip, and the effect of the tip angle on the wear of the cutter is not significant. The index of cutter consumption ratio (CCR) is proposed, and combined with the specific energy, the recommended structural and working parameters of the cutter for improving the cutting performance and reducing cutter wear are provided.