Research On Coupling Kinematics And Dynamics Of Shearer-scraaper Conveyor In Fully Mechanized Mining Face

During the cutting process of the shearer,the middle trough is not only the track on which the shearer runs,but also the main carrier of material transportation,and it is also impacted by the falling coal and rock when shearer cuts the coal wall.In addition,the middle trough will also face a variety of working conditions and complex and changeable mine environments.Therefore,the middle trough has become one of the most consumed parts of the scraper conveyor.Once a failure occurs,its maintenance is difficult and affects the production schedule,Resulting in waste of resources.This paper takes scraper conveyor as the research object,and analyzes the dynamic analysis of the middle trough on the basis of coupling action between shearer and scraper conveyor.Firstly,obtaining the coupling load of shearer and scraper conveyor.Using LS-DYNA to simulate coal cutting to obtain the external load on the drum when the shearer cuts the coal wall;Using ADAMS multi-body dynamics software to create a reasonable coupling model of the shearer and the scraper conveyor,and the three-dimensional force of the drum is applied to the center of mass of the shearer drum to obtain the load of the shearer on the middle trough of the scraper conveyor through simulation.The results show that the traction direction is the largest,the axis direction of the walking wheel is the smallest,and the vertical pressure of the smooth shoe is greater than the friction in the traction direction.Secondly,using ANSYS / LS-DYNA finite element analysis software,under the condition of flat and uneven coal and rock floor,applying the load of the shearer on the middle trough to the corresponding position,and carrying out the dynamic simulation analysis of the middle trough to obtain the load action curve of the adjacent middle trough and dumbbell pin on the middle slot,as well as the stress distribution and variation law of the middle trough.The results show that when the walking wheel of the shearer runs to the junction of the two middle trough,the interaction force between the adjacent middle slots and dumbbell pin and the middle slot is the largest.The high stress area of the middle slot occurs in the dumbbell socket at the concave end of the coal wall and the root of the rib plate on the same side,and the uneven floor will increase the stress amplitude.Then,using the ANSYS Workbench software to analyze the transient dynamics of the middle trough in the case of flat and uneven bottom plate.The analysis results are imported into ncode Design Life software to simulate the fatigue life of the middle trough under dynamic load and obtain the cloud diagram of fatigue life analysis.The results show that fatigue failure is most likely to occur at the root of rib plate of side groove of coal shovel board,and the fatigue life of middle groove will be seriously reduced when the bottom plate is not flat.This kind of situation should be avoided in practical work.Finally,using the optimization module of ANSYS Workbench to optimize the high stress and fatigue failure parts of the middle trough under dynamic load.Taking the dumbbell pit radius,rib chamfering radius and the thickness of each rib on the left,middle and right sides as design variables,and the maximum equivalent stress,maximum deformation and rib mass as target variables,a series of test designs are carried out in the corresponding optimization design module,which provides the direction for the design and optimization of the middle trough structure.