重载工况下卡车车桥轴承润滑特性分析

Lubrication characteristics analysis of truck axle bearing under heavy load condition

为提高卡车车桥轴承的润滑性能,以某型卡车车桥轴承为研究对象,在重载工况下建立考虑表面粗糙度的等温线接触弹性流体动压润滑模型。采用有限差分法对模型进行求解,分析了当量半径、润滑油粘度、粗糙度幅值以及粗糙度波长等参数变化下对润滑特性的影响。结果表明:在所研究的参数变化范围内,随着当量半径增大,油膜压力减小,油膜厚度增大;随着润滑油粘度的增大,最大压力先增大后减小,最小膜厚逐渐增大;随着粗糙度波长增大,最大压力先减小后增大,摩擦系数先减小后增大,最小膜厚变化较小;随着粗糙度幅值增大,最大压力先减小后增大,摩擦系数逐渐增大,最小膜厚变化较小。合理范围内增加当量半径、润滑油粘度取0.11~0.345 Pa·s、粗糙度波长取1.2~1.54、幅值小于0.02时润滑性能最好,同时有利于提升轴承疲劳寿命。

To improve the lubrication performance of truck axle bearings,an isotherm contact elastic-fluid dynamic pressure lubrication model considering surface roughness was established under heavy load conditions.The finite difference method was used to solve the model,and the influence of the variation of parameters such as equivalent radius,lubricating oil viscosity,roughness amplitude and roughness wavelength on the lubrication characteristics was analyzed.The results showed that the oil film pressure decreased and the oil film thickness increased with the increase of the equivalent radius within the variation range of the studied parameters.With the increase of lubricating oil viscosity,the maximum pressure increased first and then decreased,and the minimum film thickness increased gradually.With the increase of roughness wavelength,the maximum pressure decreased first and then increased,the friction coefficient decreased first and then increased,and the minimum film thickness changed little.With the increase of roughness amplitude,the maximum pressure decreased first and then increased,the friction coefficient increased gradually,and the minimum film thickness changed little.When the equivalent radius was increased within a reasonable range,the lubricating oil viscosity was 0.11~0.345 Pa·s,the roughness wavelength was 1.2~1.54,and the amplitude was less than 0.02,the lubrication performance was the best,and the fatigue life of bearings was improved.