Drum shearer is the main mechanical equipment of mechanized coal mining and plays an important role in coal mining.The study of the interaction between the cutting teeth and the coal wall is helpful to the further study of the cutting performance of the drum, so as to improve the working efficiency, stability and service life of the shearer.In view of this, it is of great significance for the optimization design of the spiral drum to study the damage and cutting performance of the cutting teeth under different parameters to the coal wall.This paper studies the cutting process of cutting teeth and drum, mainly including the following contents.

        Firstly, based on the understanding of the physical and mechanical properties of the coal wall, the discrete component coal wall model was established with the help of PFC3D software. The uniaxial compression and Brazil splitting simulation test was carried out, and the mechanical properties of the simulated coal wall were measured to match the real coal wall.Then, UG software was used to build pick type cutting model and import it into PFC3D. Linear cutting simulation was carried out for the simulated coal wall under different cutting thicknesses, and the reliability of the coal wall model was verified by regression analysis.Secondly, in the cutting thickness is 5 mm, 10 mm, 15 mm, respectively analyzes the cutting Angle of 40 °, 45 °, 50 ° and 55 ° and cut secant speed of 2 m/s, 3 m/s, 4 m/s and 5 m/s 16 kinds of micro damage cases of coal wall, cutting and cutting tooth load than energy consumption.

        Secondly, a two-tooth cutting model is established to study the cutting mechanism and cutting performance of pick-type cutting teeth under correlation cutting mode and non-correlation cutting mode.In addition, the micro-damage, load and specific energy consumption of pick-shaped cutting teeth on coal wall under 32 conditions of cutting thickness of 5 mm, 10 mm, 15 mm and 20 mm, and cutting line spacing of 10 mm, 20 mm, 30 mm, 40mm, 50 mm, 60 mm, 70 mm and 80 mm are discussed.Finally, the single-tooth rotation cutting model and the drum cutting model were established, and the cutting performance of the drum and the drum under 16 conditions of drum rotation speed of 40 r/min, 50 r/min, 60 r/min and 70 r/min, traction speed of 2 m/min, 3 m/min, 4 m/min and 5 m/min were analyzed respectively.

        Through the above research contents, the following conclusions are drawn: the correctness of simulation results and the reliability of simulated coal wall are verified by the regression analysis method;Cut secant speed, the greater the cut tooth the stronger the effect on shear rupture properties, as the cut secant line speed and the increase of the cutting Angle, the cutting tooth load and energy consumption of cutting than the trend of first increases and then decreases, the comprehensive consideration, cut secant speed should be take 3 ~ 4 m/s, cutting Angle take 45 ~ 50 ° advisable;The larger the transversal distance is, the weaker the interaction between the transversal teeth will be. The stronger the shear dislocation effect of the transversal teeth on the coal wall will be. The larger the load of the transversal teeth will be.The drum load increases with the increase of the traction speed, and with the increase of the drum speed, the drum load first decreases and then increases. When the cutting speed is 60 r/min and the traction speed is 2m/min, the drum load reaches the minimum value, which is consistent with the simulation results of single-tooth rotary cutting.The energy consumption of the cutting ratio of the drum decreases with the increase of the traction speed. When the traction speed is constant, the energy consumption of the cutting ratio decreases first and then increases with the increase of the drum speed. When the drum speed is 50 r/min and the traction speed is 5 m/min, the energy consumption of the cutting ratio reaches the minimum and the cutting efficiency is the highest.