Research On Thermo-mechanical Coupling Dynamic Behavior Of Cutting Coal And Rock With Truncated Teeth

The cutting tooth is a cutting tool for crushing coal and rock on the cutting mechanism of mining machinery.In the cutting tooth work,it interacts with coal and rock in direct contact.The working environment is harsh and the load is complex and changeable.Therefore,based on the cutting theory of coal and rock,a simulation model is established according to the structure parameters of the cutting teeth and the actual production conditions,to simulate the dynamic process of cutting coal and rock,and to study the influence of different parameters of the cutting teeth on its stress and temperature distribution,which is of great significance in optimizing the cutting teeth and improving the performance of the cutting teeth.In this paper,the pickaxe cutter is used as the research object,and the process of cutting coal and rock is simulated by ABAQUS finite element software.The results show that the higher cutting speed has no obvious effect on the position of the high stress area of the cutting tooth,but the higher the stress extreme value of the cutting tooth,the higher the number of impact times per unit time with coal and rock.When the cutting thickness exceeds 15 mm,the extreme stress value of the cutting tooth is basically unchanged with the increase of the cutting thickness,but the mean and standard deviation of the stress increase.The higher the cone Angle of tooth tip,the smaller the stress peak of truncated tooth.When the tooth tip Angle is 75°,the stress standard deviation of the truncated tooth is the smallest and the load fluctuation is the smallest.The change of installation Angle has no significant effect on the stress extreme value of the truncated teeth,and the mean and standard deviation of installation Angle at 45° are smaller than those at 40°,50° and 55°.Thermal mechanical coupled analysis was carried out on the cutting process,and get pick cutting speed,cutting thickness,tooth taper Angle and installation Angle of the cutter tooth temperature distribution and its variation law: the influence of cutting speed and cutting thickness,cutting tooth high temperature area,temperature rise rate and equilibrium temperature increase,high temperature zone position has no obvious change;With the increase of the tooth cusp Angle and the installation Angle,the position of the high temperature region of the truncated tooth gradually changed from the tooth tip to the tooth body,the tooth cusp Angle increased,the temperature distribution area of the truncated tooth increased,but the area of the high temperature region decreased,and the temperature decreased slightly at equilibrium.The mean value and standard deviation of the stress increased with the increase of the cutting temperature.The influence of cutting speed,cutting thickness,taper Angle and installation Angle on cutting performance and wear resistance of cutting teeth is obtained through analysis and research.