摩擦与配合间隙对超长大型液压缸承载能力影响规律研究

以水利工程中启闭机油缸为例,对超长大型液压缸最大轴向载荷进行计算分析.研究了两端耳环与支座轴销之间的摩擦、缸筒与活塞杆的配合间隙对轴向承载能力的影响规律,利用有限元软件ANSYS对液压缸进行非线性屈曲分析.样机试验得出最大轴向载荷为580kN,与理论计算值相差约6%,验证了理论模型的合理性.分析结果表明,由强度条件确定的极限载荷小于由稳定性条件确定的临界载荷,液压缸允许的最大轴向载荷由极限载荷衡量.随着配合间隙的减小或摩擦因数的增大,液压缸轴向承载能力增加,如当摩擦因数从0增加到0.3,允许的最大轴向载荷增加约5.5%.

Research on Effects of Friction and Fit Clearance on Bearing Capacity of Super-long Large Scale Hydraulic Cylinder

Taking the hydraulic hoist cylinder in water projects as an example, the maximum axial load of super-long large scale hydraulic cylinder was calculated and analyzed. The effects of the friction between earring and bearing shaft pin and the fit clearance between cylinder and piston rod on the axial bearing capacity were studied. The nonlinear buckling analysis of the hydraulic cylinder was carried out by ANSYS software. The maximum axial load of the prototype is 580 kN and about 6% different from that calculated by theoretical model, which verifies the rationality of the theoretical analysis. The results show that the limit load determined by strength condition is less than the critical load determined by stability condition. The maximum allowable axial load of hydraulic cylinder is determined by the limit load. The axial bearing capacity of hydraulic cylinder increases with the increase of the friction coefficient or the decrease of the fit clearance. When the friction coefficient increases from 0 to 0.3, the maximum allowable axial load increases by about 5%.