基于摩擦信号的滑动轴承接触摩擦故障的状态监测

Condition monitoring of contacting fault of plain bearings based on friction signals

摩擦信号与固有振动信号混叠造成滑动轴承的接触摩擦故障诊断困难。针对此特点,在不分离摩擦信号的条件下提出了一种基于摩擦信号强度的接触摩擦故障监测方法。该方法首先结合EMD和非线性峭度确定摩擦信号发生的时刻,然后改进灰色B型绝对关联度以计算摩擦信号对相邻固有振动信号的冲击强度,以此衡量摩擦信号的相对大小,进而监测滑动轴承接触摩擦故障。仿真和试验证明了该方法的有效性,为监测滑动轴承故障提供了一种新思路。

Contact friction fault diagnosis is diffcuh in plain bearing due to that friction signals are usually mixed with natural vibration signals. A diagnosis method for plain bearing contact friction fault was proposed based on the calculation of friction signal intensity instead of the seperation of natural vibration signals. In the method, EMD and nonlinear kurtosis were used to search the moment of friction signal appearance. Then the impact degree of friction signals on natural vibration signals was calculated by an improved absolute grey relational degree of B-mode. Finally, the calculation results were used to estimate the magnitude of the friction signal and to diagnose the contacting fault of plain bearing. The proposed method was applied to simulated signals and actual signals. The analysis results demonstrate the effectiveness of the proposed method and offer a new ideas to diagnosis the plain bearing fault.