Study of grease behaviour in a starved elastohydrodynamically lubricated contact

Abstract

This paper is an experimental study of grease lubrication in a starved elastohydrodynamic lubricated (EHL) contact. Lubricating film thickness is measured with tribological experimental device ball-on-disc using optical interferometry and high speed camera. The lubricants used were commercial greases with a various kinematic viscosities, additives and thickeners formulated for low and high-speed applications. The experiment is aimed at a comparison of results acquired by ball-ondisc device and full scale axial bearing. In addition, this paper also investigates the influence of number of the rolling elements (overrolling time) on the resulting film thickness. Experiments confirm the presence of replenishment mechanism caused by relative motion of the surfaces, which generates base oil flow into the inlet of the contact.