滚动轴承润滑膜厚及保持架转速的超声测量

Ultrasonic Measurement for Lubrication Film Thickness of Rolling Bearings and Rotational Speed of Cages

滚动轴承的运行稳定性与钢球和内外圈之间的润滑状态密切相关,膜厚则是表征轴承润滑性能的重要参数。基于超声弹簧模型建立了膜厚测量模型并搭建了试验台,通过试验台模拟球轴承的运行状态并测量钢球周围以及沿滚动方向的膜厚分布,分析了转速对最小膜厚的影响;同时,根据连续2个钢球通过探头正下方的时间间隔计算保持架转速,分析得到了不同重复频率所能测量的保持架转速范围。试验结果表明,膜厚的实际测量值与理论值吻合较好,保持架转速的实际测量值与纯滚动条件下的理论转速一致性良好,可用于轴承打滑状态的评估。

The operational stability of rolling bearings is closely related to lubrication state between steel balls and inner/outer rings,and the film thickness is an important parameter to characterize the lubrication performance of the bearings.Based on ultrasonic spring model,a film thickness measurement model is established,and a test rig is built.The film thickness distribution around steel balls and along rolling direction is measured by simulating the operational state of ball bearings,and the effect of rotational speed on minimum film thickness is investigated.In addition,the rotational speed of cages is calculated according to time interval between two consecutive steel balls passing directly below probe,and the rotational speed range of cages that could be measured with different repetition frequencies is analyzed.The test results show that the actual measured value of film thickness is in good agreement with theoretical value,and the actual measured value of rotational speed of cages also matches well with theoretical value under pure rolling condition,which can be used to evaluate the bearing skidding.