Recommended Alarm Criteria for Bearing Condition Assessment Using Enveloped Acceleration

This application note presents a set of guidelines for initially establishing Alert and Danger alarm thresholds for enveloped acceleration measurements for early detection of rolling element bearing damage. The criteria recommended herein should be used to determine initial alarm thresholds only. As with all commonly published severity charts and tables, this method provides target thresholds for new, refurbished and recently maintained equipment. Once a good operating baseline is established and sufficient data and experience have been acquired for high confidence statistical alarm calculation on a point-by-point basis, the prudent analyst will abandon these guideline thresholds in favor of an automatically calculated trend-based or statistically-based change technique. 

Specific details on the enveloped acceleration technique may be found in the SKF Reliability System’s Application Note, publication CM3013, “Frequency Asked Questions About Enveloping”.