A defect size estimation method based on operational speed and path of rolling elements in defective bearings

This paper describes the effect of inertia and centrifugal force that act on a rotating rolling element in a defective bearing, on the measured vibration signature. These effects are more pronounced as the speed of components increases. Significant speed-dependency of the characteristic events that are generated at the angular extents of the defect are shown by simulation and experimental measurements. The sources of inaccuracy and the speed-dependency in the existing defect size estimation algorithms are explained. The analyses presented in this study are essential to develop accurate and reliable defect size estimation algorithms. A complete defect size estimation algorithm is proposed that is more accurate and less biased by shaft speed when compared with existing methods.