Study On The Performance Of Multi-point Impact Cutting Drum

Coal will still occupy an absolute dominant position in China’s energy system in the next few decades,but with the depletion of high-quality coal seam reserves,the depth of coal mining in China will continue to increase,deep mining will become the normal in the development of coal resources,the geological conditions will be more complex in the future,and the hardness of coal and rock will continue to increase.In recent years,the mining technology and theory of hard coal and rock are being improved gradually,but the development of mining equipment is relatively slow.In order to solve this problem,based on the research result of"hydraulic-aided impact cutting tooth project"in Shenhua Shendong enterprise,this paper introduces a multi-point impact cutting drum for high-efficiency coal breaking equipment.It is of theoretical and practical significance for the development and upgrading of coal mining equipment and the improvement of mining efficiency of non-quality coal seam.This paper analyzes the new research achievements and the performance parameters of shearer’s drum,briefly summarizes the coal-rock crushing method and its constitutive model,compares the traditional cutting drum with the rock-breaking principle,constructs the multi-point impact-type rock-breaking model,analyzes the influence factors and performance evaluation index of coal-breaking efficiency,and determines the numerical simulation parameters and scheme.The simplified geometric model of shearer cutting drum is established by CATIA software,the similar structure discrete element model is established in EDEM according to the physical and mechanical characteristics of coal and rock medium,and the multi-point impact cutting drum working numerical simulation model is constructed according to the working process of the drum.The results show that:Taking the coal drop rate as the evaluation index,the main order of influencing factors is:A>C>B（coal wall hardness>drum rotation speed>impact frequency）,and the optimal scheme combination is A₂B₁C₃（coal wall hardness:f5,impact frequency f=4Hz,drum rotation speed n=40r/min）.Taking the energy consumption of cutting ratio as the evaluation index,the main and secondary order of the influencing factors are C>A>B（drum rotation speed>coal wall hardness>impact frequency）,and the optimal scheme combination is A₂B₁C₃（coal wall hardness f5,impact frequency f=4Hz,drum speed n=40r/min）.Further introduction of matrix analysis,the primary and secondary order of the influence of each factor on the index value of orthogonal test is C>A>B（drum rotation speed>coal wall hardness>impact frequency）,and the weight of factor A₂,B₁and C₃is the largest,so the best scheme is A₂B₁C₃,that is,the hardness of coal wall is f5,the impact frequency is f=4Hz,and the drum speed is 40r/min.At last,number of falling particles of multi-point impact drum is 29131 higher than that of non-impact drum 24.86%under the same conditions,the energy consumption of the impact-free drum cutting ratio is 0.7423 k W·h/m³,which saves 0.2053 k W·h/m³compared to the impact-free drum.Therefore,the optimal parameter combination of multi-point impact roller is reasonable,and the performance is better than that of traditional impact-free roller.