Effect of speed, load, and grease type on the film thickness in grease-lubricated cylindrical roller bearings

The lubrication behavior in grease-lubricated cylindrical roller bearings varies with operating conditions. Understanding the influence of speed and load on film thickness—particularly during the early period immediately following the churning phase—can enhance the knowledge of the lubrication mechanisms and support more accurate predictions of grease performance. In this study, the effect of speed and load on the film thickness in a grease-lubricated cylindrical roller bearing is investigated via the electrical capacitance method, using two different greases. Experimentally measured film thickness exhibits different trends with increasing speed at a fixed load for both greases. In addition, at a fixed speed, grease type-dependent dynamics in the film thicknesses are also observed as the load changes.