液压支架在冲击荷载下的运动状态分析

Analysis of Movement State of Hydraulic Support under Impact Load

针对煤矿回采工作面顶板活动诱发液压支架冲击性损伤的现状,为解决支架稳定性不足导致工作面失稳或报废的问题,运用动力学原理分析冲击荷载下液压支架的运动状态,获得描述支架支柱转动速度的解析式,显示支柱转速由冲击荷载值、支架几何尺寸与质量、支架支柱倾角等多因素共同决定。结合算例,重点分析了支柱转速随转动历时和支柱倾角的变化规律,结果表明:受冲击作用的支柱呈变加速度转动;支架前柱的稳定性弱于后柱;将液压支架前、后柱倾角分别设置成120°~130°和70°~90°有益于提升支架的抗冲击性能。

In view of the current situation of the impact damage of the hydraulic support caused by the roof movement of the coal mining face,in order to solve the problems that the stability of the support is insufficient and the working face is unstable or abandoned,the movement state of the hydraulic support under the impact load was analyzed by using the dynamic principle,and the analytical formula describing the rotation speed of the support column was obtained,which showed that the rotation speed of the support is determined by many factors such as the impact load value,the mass and the geometric dimension of the support and inclination angle of support column.Combined with an example,the change rule of the rotation speed of the column with the rotation time and the inclination angle of the column is emphatically analyzed.The results show that the column under the impact is rotating with variable acceleration,and the stability of the front column of the support is weak compared with that of the rear column.It is found that setting the inclination angles of the front column and the rear column of the hydraulic support to 120°~130°and 70°~90°respectively is beneficial to improve the shock resistance of the support.