Investigation of the High Speed Rolling Bearing Temperature Rise With Oil-Air Lubrication

Abstract

The oil-air lubrication system has been widely used for rolling ball bearing. However, as the rotation speed increases, the temperature rise will increase dramatically, resulting in shortening the service life of the ball bearing. The existing literature has offered valuable fundamental data about the oil-air lubrication of rolling bearing; however, there are still some problems that concerned the oil-air lubrication, which are not addressed. In this study, an experiment setup to investigate the oil-air lubrication for the high speed ball bearing has been developed, and performance tests of hybrid ceramic and steel ball bearings under the extensive operating conditions including oil-air supply pipe length, bearing preload, lube interval, oil type, oil viscosity, nozzle design, and rotation speed have been conducted. The test results show that the bearing has the lowest temperature rise with the pipe length of 1.5 m. For the steel ball bearing, the proper preload decreases with increasing of the rotating speed, and the temperature rise of the hybrid ceramic ball bearing is not sensitive to the axial preload. There exists a proper amount of lubricant for the bearing at each rotational speed; and a larger amount of lubricant is required for the bearing as the rotating speed increases. The tested bearings under different speeds have almost the same lowest temperature rise under the lubricant with the viscosity of 100 cSt; a higher or lower viscosity will increase the bearing temperature rises. The nozzle design is an important factor to affect the temperature rise of the ball bearing, and the suitable geometric parameter of the nozzle is closely related to the cage landing method of the bearing. The temperature rise of tested bearings increases with the increase in the rotation speed; and the hybrid ceramic ball bearing always has a lower temperature rise than that of the steel ball bearing at the same operating conditions.