圆锥滚子轴承滚子/滚道副的脂润滑热成膜性能

考虑圆锥滚子轴承的非等截面属性和脂润滑状态，基于润滑脂Power-law流变模型，结合脂膜能量方程和固体热传导方程，建立轴承滚子与滚道接触的非等温脂润滑模型，分析滚子修形、打滑、歪斜和倾斜等对接触副脂润滑热成膜性能和拖动性能的影响. 结果表明：在未发生倾斜或歪斜时，Lundberg对数母线修形滚子的最小膜厚略大于切交母线修形滚子，而压力峰值略小于切交母线修形滚子. 在考虑温度效应后，脂膜厚度减小，压力峰值增大. 倾斜运动导致滚子主要承载端的脂膜压力和颈缩量增加，膜厚减小，因此滚子修形应考虑倾斜运动的影响；歪斜运动对膜厚和压力分布的影响则相对较小. 滚子/滚道副的脂润滑拖动系数随打滑加剧呈现先增大后减小的趋势.

Thermal film-forming ability of grease lubrication at roller-raceway pair in tapered roller bearings

Considering non-equal section properties and grease lubrication condition of tapered roller bearings, the grease thermal lubrication model at the roller-raceway pair was established based on the Power-law rheological model of greases, combining with the energy equation of grease film and the heat conduction equation of the roller/raceway. The effects of roller crowning, sliding, tilting and skewing on the grease lubrication and traction action were analyzed. Results show that when no tilting or skewing occured, the minimum film thickness of the Lundberg crowned roller was slightly thicker than that of the cut-off crowned roller, while the film pressure peak was slightly thicker than that of the cut-off crowned roller. After considering the temperature effect, the film thickness decreased and the pressure peak increased. The tilting motion causes the reduce of the minimum film thickness and the increase of the film pressure and the necking at the main loaded end. Therefore, the effect of the tilting motion should be considered when crowning the tapered roller. The skewing motion brings less effect to the grease film thickness and pressure distribution. The traction coefficient at the roller-raceway pair increases first and then decreases with aggravation of bearing sliding.