Experimental exploration for the performance improvement of a thrust ball bearing using circumferential micro-grooved races

Abstract

This paper presents the findings of an experimental study performed for exploring and improving the tribodynamic performance behaviours of a thrust ball bearing employing circumferential micro-grooves on the stationary upper race. Investigations were conducted using oil and grease lubricants and operating the bearings at light loads (in the vicinity of requisite minimum loads characterised by pH = 0.4 and 0.6 GPa) and speeds varying in the range of 1.8–4.0 m s−1 at the ambient condition. The effects of micro-grooved stationary races on frictional torque, temperature rise and vibrations of the bearings were measured and have been discussed herein. The surface topographies of races and balls of used test bearings were examined after finishing the experiments for extracting the surface topographies based technical information. Significant reductions in the magnitudes of frictional torque (14%–21%), bulk temperature rise of race (14%–26%), vibrations (7%–34%) were found with micro-grooved bearings (pair of conventional moving lower races and micro-grooved upper stationary races) in comparison to the conventional bearings (pair of conventional races). Moreover, the oil lubricated micro-grooved bearings yielded substantial improvement in the tribo-dynamics as compared to grease lubricated case irrespective of the operating parameters i.e. loads and speeds.