滚子歪斜对滚子副润滑性能的影响

Influence of Roller Skew on the Lubricating Performance of Roller Pairs

为研究圆柱滚子副中的滚子歪斜效应,建立滚子的竖直歪斜和水平歪斜2种弹流润滑模型。求得滚子竖直歪斜时等温条件下有限长线接触润滑问题的完全数值解,分析滚子竖直歪斜角和滚子端部圆角半径对滚子副润滑性能的影响,并将竖直歪斜滚子副润滑的理论结果与试验结果进行比较;利用坐标变换法求得滚子水平歪斜条件下的弹流数值解,分析滚子水平歪斜角对膜厚和压力的影响,并给出了相应的试验结果。结果表明,滚子的竖直歪斜极易引起滚子偏磨,但通过滚子端部修形可缓解油膜压力及厚度沿接触线长度分布不均的程度;滚子一定范围内水平歪斜会导致接触区油膜厚度和压力变化,尤其油膜出口颈缩和第二压力峰变化明显;与滚子水平歪斜相比,滚子的竖直歪斜对润滑更为不利。

In order to investigate the roller＇s skew effect in cylindrical roller pairs, elastohydrodynamic lubrication （EHL） models of a vertical and a horizontal skew roller were built. A full numerical solution for isothermal finite line con- tacts EHL problem under a vertical skew roller condition was obtained, the effects of the roller＇s vertical skew angle and the end profile radius on the lubricating performance were analyzed, and the theoretical results were compared with the ex- perimental results. A numerical EHL solution for a horizontal skew roller was achieved with the method of coordinate trans- formation, the influence of the roller＇s horizontal skew angle on the film thickness and pressure was given, and the corre- sponding experimental results were provided, too. Results show that, partial wear easily occurs for the vertical skew roller. However, the uneven distribution of pressure and film thickness along the contact length can be relieved by profile modification of the end part of the roller. Variations in the film thickness and pressure, especially the film thickness in exit restriction and the second pressure peak of the contact area can be caused by a certain range of a horizontal skew angle of the roller. Compared with the results of roller＇s horizontal skew, the vertical skew is more harmful to the lubrication of roll- er pairs.