环境因素对推力轴承润滑膜超声检测精度的影响

Influence of Environmental Factors on Ultrasonic Testing Accuracy of Thrust Bearing Lubricating Film

核主泵推力轴承摩擦副采用的润滑介质黏度较低且轴承工作于高温高压等极端工况下,采用超声技术对润滑膜分布进行精确测量时,要考虑环境因素的影响。建立核主泵推力轴承润滑膜分布的超声检测模型,并在模拟试验台上进行推力润滑状态的实测。在对测试结果的分析中考虑测量时温度和压力等环境因素的影响,分析环境因素对超声检测精度的影响程度。结果表明:在启、停阶段推力轴承处于边界润滑状态,考虑温度和压力影响时润滑膜厚值最大会增大加38.5%;在额定转速下推力轴承处于流体润滑状态,考虑温度和压力影响时润滑膜厚值最大会增大加39.8%。

The lubricating medium used in the friction pair of thrust bearing of nuclear main pump has low viscosity,and the bearing works under extreme working conditions such as high temperature and high pressure.When using ultrasonic technology to accurately measure the distribution of the lubrication film,the influence of environmental factors should be considered.An ultrasonic testing model of the lubrication film distribution of thrust bearing was established,and a actual measurement of thrust lubrication state was conducted on a simulation test bench.In the analysis of the test results,the influence of environmental factors such as temperature and pressure during the measurement was considered,and the degree of influence of environmental factors on the accuracy of ultrasonic testing was analyzed.The results show that the thrust bearing is in the boundary lubrication state during the start and stop stages,and the lubrication film thickness value is increased by 38.5%when considering the influence of temperature and pressure.The thrust bearing is in a fluid lubrication state at the rated speed,and the lubrication film thickness value is increased by 39.8%when the influence of temperature and pressure is considered.