Analytical model of rolling element bearing for studying its wear modelled as change in its clearance

Abstract

Machinery with components having rotary relative motion have bearings in between them for reduction in friction during motion. Owing to simplicity in construction and ability to operate at high speeds, rolling element bearings are highly sought type of bearing. During operation the rolling element bearings are subjected to load and heat due to which they are subjected to wear. This wear is persistent and leads to increase in clearance in the bearing and tends to generate higher vibrations. Hence, the objective of this study is to assess the effect of wear modelled through clearance on the bearing vibrations. A four degree of freedom model is presented and based on Hertzian theory of contact the contact between rolling elements and raceways is modelled. The effect of clearance on accelerations and force acting on rolling element is presented. The results ascertain that as the clearance in the bearing increase the vibration levels of the bearing increases. Further, the analysis of variation in force on rolling element with change in clearance shows that the rolling elements experience higher force as clearance in the bearing increases.