Experimental Evidences in the Monitoring of Rolling Element Bearings

The identification of the damage type in rolling element bearings is usually performed by means of Envelope Analysis of vibration signal. This method is based on the identification of bearing damage frequency components in the so-called Envelope Spectrum. Conversely, the monitoring and the evaluation of the trend of a suitable fault indicator are complex tasks to be performed. The fault indicator must be robust against variations of system operating conditions and external vibration sources to avoid misleading results. In the paper, the case of a rolling element bearing in which the defect develops until a severe failure is described as well as the algorithm implemented for alarm signaling.