Discrete Element Simulation Of Spiral Blade Wear Of Shearer Drum And Optimization Of Coal Loading Performance

Coal loading is the main function of the spiral blade of the shearer drum.The blade wear failure is not easy to repair and the replacement cost is high,which will reduce the working efficiency of the shearer.In this paper,the analysis and research on the wear of spiral blades are carried out.After optimization to ensure the blade coal loading and drum cutting performance,the blade wear is minimized,and the production efficiency of the drum is comprehensively improved and the service life of the drum is extended.According to the multi-objective optimization of the blade coal charging performance and the drum cutting performance,the drum is proposed to respond to the coal seam with different gangues with adaptive speed regulation and cutting strategies,and the spiral angle of the drum blades is analyzed and optimized to further improve the working efficiency of the drum.Taking the spiral blade of the MG2×55/250-BW thin seam shearer drum as the research object,setting the relevant parameters of the coal wall model based on the occurrence conditions of the17-layer coal in Yangcun Mine of Yankuang Group,and using the Hertz-Mindlin with EDEM The collision and friction between the virtual coal and rock mass of Archard Wear model and the drum are simulated by the coupling of the three-dimensional modeling software PROE and the discrete element numerical simulation software EDEM,and the drums and different coals with different traction speed,drum speed and blade helix angle are established respectively.The coal wall coupling of the firmness coefficient obtains the wear position of the drum blade,the load change and the wear change law under different working conditions.The results showed that the wear at the end of the blade was the most prominent,and the blade edge and tooth seat root were also more serious.Blade wear increases with the increase of traction speed,helix angle and coal rock firmness coefficient,and decreases with the increase of drum speed.Through orthogonal experiments,among the four influencing factors of traction speed,drum rotation speed,blade helix angle and coal rock solidity coefficient,the analysis shows that the impact on blade wear from large to small is drum rotation speed and coal rock solidity.Coefficient,traction speed,blade helix angle.Combining the analysis of actual working conditions,comprehensively considering the coal loading rate,productivity,lump coal rate,cutting specific energy consumption and blade wear of the shearer,a multi-objective optimization model is constructed to ensure the working performance of the drum and reduce the blade Wear,solve the optimal drum speed and traction speed.That is,when the coal rock solidity coefficient is 3.5,the drum speed is 80.65 r/min,the traction speed is4.23 m/min,the blade lift angle is 11.56°,the coal rate is 43.29%,the productivity is 214.1149 t/h,and the maximum cutting area is 1217.0 mm~2,the cutting specific energy consumption is 0.8612k W·h/m~3,and the total blade wear depth is reduced to 0.25416 mm when the drum is cutting for10 s.In order to improve the working performance of the drum,a shearer adaptive cutting strategy based on multi-objective optimization of memory drum speed and traction speed is designed.Aiming at four coal seams containing gangue,genetic algorithm is used to find the best matching value of drum speed and traction speed.The self-adaptive cutting judges the hardness of the coal seam according to the stator current,takes the optimal drum speed and traction speed as the database memory,and realizes the self-adaptive mining of the shearer through adaptive correction.According to the influence of the blade helix angle on coal loading and drum cutting performance,the helix angle of the drum blade is optimized,that is,the blade angle is designed to be a variable helix angle of 10°?16°to conform to the direction of coal flow.After comparing the data before and after optimization for the coal conveying space,it is found that the total blade wear depth when the drum is cut for 10 s is reduced by 0.02317 mm,the coal loading rate of the drum is increased by 1.3%,the productivity remains unchanged,and the maximum cutting area is increased by 68.94 mm~2.Cutting specific energy consumption is reduced by 0.011 k W·h/m~3.