Comparison of Models for Rolling Bearing Dynamic Capacity and Life

摘要

The widely used Lundberg-Palmgren rolling-element bearing fatigue life model was developed inthe 1940’s based on Weibull analysis and on life data for bearings made from the materials existingat the time. In the 1980’s, Zaretsky proposed a life model also based on Weibull analysis, buteliminating the Weibull slope in the critical shear stress exponent and the term involving the depthto the critical shearing stress. Over the years, significant advancements have been made inmaterials, lubricants and manufacturing techniques. As a result, life-modeling algorithms haveadvanced in two areas: modification of the basic life prediction model itself, and algorithms tocalculate life modification factors for Lundberg-Palmgren life predictions. Existing life models havethe elastic properties embedded in the model constant; therefore, there is no provision to varythese properties in the analysis. The objectives of this paper were (1) generalize the modelformulation to allow arbitrary elastic properties of the materials to be inputs to the model, (2)correlate model predictions with experimental data to derive the model constants and (3) comparelife predictions of the original and modified Lundberg-Palmgren and the Zaretsky models. Themodified analysis considers the variation in elastic modulus with temperature.