Analysis On Impact Characteristic Of Shearer Picks

Pick is a cutting tool of shearer, which is also the direct working part of shearer. because of the poor working environment, pick is also the main parts which have to be replaced often. The mechanical properties of pick play a significance important part for improving productive efficiency and economic efficiency. According to the force and possible fault in the operation, static load and dynamics of picks during the operation are detail analyzed and researched in the thesis.Based on the impact dynamics theory and analysis of explicit integration algorithms, the basic technical process of the pick dynamics by using finite element method (FEM) is established in the paper. By using ANSYS/LS-DYNA, the analysis model of static and dynamic analysis. The stress and strain distribution under static force of pick is obtained. The equivalent stress distribution, velocity, acceleration and energy characteristics of pick under impact dynamics condition, and the effect of the different install binding on the mechanical properties is especially compared.The main conclusions in this thesis are as followings:(1) The maximum equivalent stress of pick occurs is in the head in the static load,, and the closer to the head the stress is bigger, but the maximum strain is in the welded zone. Therefore, it is possibly failure reason of pick set that the head fall off.(2) It is easy to fatigue failure during the impact load, because stress is increased and decreased repeat. The shear stress plays a major role in this kinds loading.(3) The stress, velocity, acceleration transient is a larger under impact loading as the speed increase. So, the larger pick speed during operations is limited.(4) The stress is smaller in the head and changes are not obviously in the tail because of the pick which is installed strongly, kinetic energy loss more, and internal energy increase less. It's good for cutting coal.The research results in this thesis provide a theoretical basis for the pick optimized design and experimental study.