A numerical simulation of the coal cutting process using a conical pick at different cutting angles

Abstract

This paper presents the results of a numerical simulation of coal cutting with a tangential rotary pick using the LS-DYNA software suite. The aim of the study was to evaluate the impact of the pick installation angle on the force parameters of the cutting process. The rock mass was represented by a deformable coal block, while the cutting tool was modeled as a rigid body. The installation angle varied from 45° to 53° with a step of 2°. The mechanical behavior and failure of coal were described using the Holmquist–Johnson–Cook material model with account of the accumulated damage and removal of the failed elements. The calculation cases were compared using the mean and peak cutting forces, the mean and peak normal forces, and the failure pattern in the cutting zone. It was found that the dependence of the force parameters on the installation angle is nonmonotone. The minimum values of the mean cutting force, mean normal force, and peak cutting force were obtained at the installation angle of 51°. At this angle, the mean cutting force was 1.04 kN, the mean normal force was 0.27 kN, and the peak cutting force was 2.74 kN. The results indicate that the most efficient cutting mode is the chip-and-shear mode, in which the failure zone propagates from the pick tip toward the free surface of the coal block. The obtained results can be used to select rational pick installation parameters for the shearer drums of continuous miners.