Novel Threshold Calculations for Remaining Useful Lifetime Estimation of Rolling Element Bearings

摘要

The prognostics objective is to avoid sudden machinery breakdowns and to estimate the remaining useful life after initial degradation. Typically, physical health indicators are derived from available sensor data, and a mathematical model is tuned to fit them. The time it takes for the model to reach a failure threshold is the estimated remaining useful life. The failure threshold may be determined from historical failure data, but that is not always readily available. ISO standard 10816-3 defines permissible velocity vibration levels for machines that may be used as a failure threshold. However, velocity vibration is not suitable for bearing prognostics due to the effect of integration from acceleration. In this paper, the drawbacks of velocity vibration are explained, and two new failure thresholds using acceleration vibration data are proposed. Results from three run-to-failure tests are provided to show the performance of the proposed failure thresholds.