通过案例研究了液压支架工作过程中推移千斤顶活塞杆弯曲失效问题。对综采面煤层赋存条件、案例特点、推移千斤顶过载的可能性及其稳定性、受力关系、检修技术方案等进行全面分析。结果表明:修复利用活塞杆的残余变形导致推移千斤顶失效。提出了改进措施。 The problem of bending failure of piston rod of jacking jack during the work of hydraulic support was studied by case study. Carrying out a comprehensive analysis of the coal mining conditions, the characteristics of the case, the possibility of overloading the jacking overloading, the stability of the coal seam, the force relationship, and the technical solutions for overhaul and so on. The results show that repairing and utilizing the residual deformation of piston rod lead to the failure of jacking jack. Put forward the improvement measures.