The fault simulation experiment and feature extraction of rolling bearing based on casing measuring point

In this paper, the reliability of the rolling bearing fault feature extraction based on casing vibration signals is discussed. Through the fault simulation experiment of rolling bearing, the vibration data of the outer ring fault, inner ring fault and rolling element fault, which respectively comes from bearing block measuring point and casing measuring point, is acquired. Then this paper analyzed the data from the time domain, frequency domain and amplitude domain. Analysis results show that, compared to the bearing block measuring points, due to the attenuation of the pulse signal of the fault in the transmission way and the increase of signal to noise on the casing, the fault features of casing vibration signals are significantly weakened. The envelope demodulation, FFT change on the vibration signal of casing directly cannot extract the fault characteristics. However the fault characteristic frequency can be extracted from the appropriate resonance frequency band. The results provide a reference for the fault feature extraction of rolling bearing based on the signal of casing.