Influence of base oil and degree of refining on friction loss by meshing of spur gears

Abstract

The purpose of this paper is measurement of friction loss by meshing of Spur Gears and evaluation of the influence of base oils. Three types of lubricant oil which is Mineral-Oil-Based Automatic Transmission Fluid (Gr.Iand Gr.III) and Polyalphaolefin -Based Automatic Transmission Fluid (Gr.IV) were used. The measurement was carried out in case of three different oil temperatures, and three different circumferential speeds. Frictional loss is measured by using the back-to-back gear tester. In order to separate the friction loss, windage loss, churning loss, seal loss and bearing loss were individually measured. As a result of these measurements, two tendencies were shown. Firstly, as the oil temperature increases, friction loss is decreased. Secondly, friction loss also decreased with increasing circumferential speed. Lowly Viscosity and lowly Pressure viscosity coefficient is effective for the power transmission efficiency of the gear.