基于电容法的脂润滑球轴承弹流膜厚影响因素研究

Study of the Impacting Mechanism of EHL Film Thickness of a Grease Lubricated Ball Bearing Based on Capacitance Method

采用电容法对脂润滑球轴承的弹流膜厚影响机制进行了研究,分别在不同轴承转速、轴向载荷、润滑脂类型以及滚珠数量条件下对弹流膜厚值进行测量。结果表明:轴承转速的提升会导致温度的变化,虽然不同润滑脂具有不同的剪切稳定性,但所有润滑脂的标准化膜厚值变小,即导致更恶劣的乏油程度;载荷的变化仅对剪切稳定性低的润滑脂的弹流膜厚值有影响;而轴承滚珠数量减半后,在每个滚珠所受载荷不变的情况下,润滑脂所受剪切作用减少,导致轴承的乏油程度更加严重。研究表明,脂润滑球轴承的弹流膜厚值受到多因素的影响,需要对不同情况进行单独分析。

The impacting mechanism of elastohydrodynamic lubrication(EHL)film thickness of a grease lubricated ball bearing was studied by capacitance method.The EHL film thickness was measured under different bearing speed,load,grease type and bearing ball number.The results show that the increase of bearing speed will lead to variations in temperature,although the shear stability of the tested greases is different,but the relative EHL fim thickess of all greases is reduced,which leads to more serious starvation level.The change of load only affects the EHL film thickness of the grease which has a low shear stability.When the number of bearing balls is reduced by half while the load per ball is kept the same,greases would experience less shear which leads to more serious starvation level.The research shows that the EHL film thickness of the grease lubricated ball bearing is affected by many factors,and it needs to be analyzed separately in different cases.