Frictional Contact Analysis And Bionic Optimization Design Of Scraper Conveyor Middle Slot

The life span of the scraper conveyor directly determines the economic benefits of the coal mine,while the middle slot life is an important indicator of the life of the scraper conveyor.As the main bearing parts of the scraper conveyor,a large number of middle slot are scrapped due to severe wear.In order to improve the wear resistance of the middle slot of the scraper conveyor,this paper applies the non-smooth wear-resistant theory to the middle slot,which opens up a new way to improve the middle slot life.In this paper,the finite element simulation of the frictional contact behavior of the middle slot with the scraper and the material under different working conditions was carried out.It is found that the friction contact stress between the scraper and the middle slot is 3 to 5 times of that of the coal and the middle slot,and more than 2 times of that of the rock and the middle slot,so the friction contact between the scraper and the middle slot plays a more important role on the wear and tear of middle slot.In addition,the contact stress on the surface of the middle plate with both ends of the scraper and the fastening bolts is about 9times that of the remaining area,which in turn results in significant wear marks,which is consistent with its actually worn status.Based on the non-smooth wear-resistant theory,the bionic optimization of the middle slot was carried out by using the pits on the surface of the middle plate.The orthogonal test design of L₉?3⁴?four factors and three levels was used.The structural static analysis and frictional contact analysis of 9 groups ofthe bionic middle slot samples and the original middle slot samples were carried out respectively,and the simulation results were compared.The results show that the pits have stress relief effect,moment effect,edge strengthening effect and the effect of collecting debris and so on.So the pits reduce fatigue wear,abrasive wear,impact wear,adhesive wear,thermal fatigue and thermal wear of the middle slot.Based on the middle slot studied for the subject,the range analysis and index estimation of orthogonal test simulation results was carried out.The primary and secondary order of pit morphology parameters?pit diameter,pit depth,pit cross / longitudinal spacing?that effect the maximum,mean and standard deviation of static equivalent stress and friction contact stress are obtained.The preferred pit morphology parameters which make the stress related values above smallest are obtained.Then,the influence of the parameters of the pits on the wear resistance of the non-smooth surface was studied by the contact analysis of the rectangular blocks.The results show that the surface of the pits is easily deformed to produce more compressive and bending strain energy.The pits have the effect of releasing stress,and thus improve the wear resistance of the non-smooth surface of the pits.At the same time,with the increase of the length and spacing of the pits,the wear resistance of the non-smooth surface increases first and then decreases,and there is an optimal value.With the increase of the pit depth,the wear resistance of the non-smooth surface increases small.Finally,combined with the results of simulation analysis,the experiment design of the middle slot bionic optimization is designed,which is instructive for the next step.