Coal falling trajectory and strength analysis of drum of shearer based on bidiectional coupling method

Abstract

The cutting and crushing of coal and rock containing gangue is the result of the coupling effect of multiple factors. The geometric parameters of the working mechanism, the Kinematics parameters of the shearer, and the physical and mechanical properties of the coal and rock to be cut will all affect the cutting and crushing process of the shearer. In order to study the coal falling trajectory of spiral drum cutting coal and rock, obtain its optimal cutting parameters, and achieve efficient cutting of spiral drum, a coal falling trajectory and strength analysis of drum of shearer based on bidirectional coupling technology was proposed based on particle discrete element contact theory and virtual prototype technology. The DEM-MFBD (Discrete Element Method Multi Flexible Body Dynamics) two-way coupling technology was used to realize the cutting and interactive information of the spiral drum on the complex coal seam with gangue. Construct the cutting conditions of the spiral drum under different cutting depths, rotational speeds, and traction speeds. Monitoring the movement status of coal and rock particles under different working conditions. Compile the coal falling trajectory equations of coal and rock particles under different working conditions and draw the coal falling trajectory curve. The optimal coal loading rate was used as the measurement standard for the coal falling trajectory, and the optimal coal falling trajectory of the drum was obtained through full factor experiments. Extract the load of the drum and pick, analyze their stress and deformation, and perform fatigue life analysis on the pick with the highest stress. The results indicate that the maximum deformation occurs on the cutting teeth that are cutting hard gangue. The stress of the tooth seat is mainly concentrated at the root of the tooth seat, and its maximum equivalent stress is less than the yield limit value of the selected material. Therefore, the material selection and structural design of the drum are safe and reliable. By building a coal mining machine cutting coal and rock experimental platform, monitoring the working status of the designed spiral drum, it meets the usage requirements. Based on industrial experiments conducted underground, the measured average coal loading rate of the shearer drum was 46.31%, achieving stable operation and verifying that the designed drum of shearer has efficient cutting ability.