Experimental and theoretical design for decreasing wear in conical picks in rotation-drilling cutting process

Serious wear-out failure in conical picks leads to low working efficiency when mining protective seams using a coal auger. In this study, to decrease the wear of conical picks in the rotation-drilling cutting process, an interference model of rotation-drilling cutting is established according to coal cutting theory. Then, laboratory rotation-drilling cutting experiments with 28 different cutting angles δ and rotation angles ε are realized on large blocks of test coal wall using one type of conical pick to verify the interference model. The experimental results show that the wear of picks increased gradually with an increase in rotation angle and a decrease in cutting angle. The rotation-drilling cutting experiments verify the correctness of the interference theory model. It is preferable to choose a small rotation angle and large cutting angle when deciding on the installation parameters of conical picks in the theoretical range.

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