Experimental investigations to analyze surface contact fatigue wear by using a dynamic response of the roller bearing system

In modern engineering applications, rolling element bearings are the essential machine components in rotating machinery, which are used to constrain the desired motion and reduce friction between two rolling/sliding members of machines. Under the normal operating conditions, increase in the fatigue load cycles on the bearing contact surfaces result in surface fatigue faults viz. micro pitting, macro pitting, spalling and scuffing thereby causing damage to roller bearing components. These defects result a gradual increase in vibration levels, which lead to negative impact on the performance of rotating machinery. Hence, in order to maintain better operating performance of rotating machines it is essential to keep a track on operating parameters of roller bearing. In the present work, the experiments were carried out to assess wear propagation on contact surfaces of the roller bearing by using tribological and vibration parameters such as vibration signals, lubricant film thickness, shear rate of lubricant and wear propagation on the bearing contact surfaces. Dowson and Higginson’s equation was used to estimate the specific film thickness between rolling elements of the bearing. Results obtained from the experimental investigations provided a good correlation between an increases in surface fatigue wear and corresponding effects on transition in lubrication regimes, increase in vibration levels, variations in rheological properties of lubricant and wear severity developed on the contact surfaces of the roller bearing. The proposed approach can be used as a promising tool to asses surface fatigue wear developed on roller bearing contact surfaces.