Gao Chuangkuan

Qi Xiumei

College of Mechanical Engineering,

Taiyuan University of Technology,

Taiyuan 030024, China

Xiong Shibo

Institute of Mechano-electronic
Engineering,

Taiyuan University of Technology,

Taiyuan 030024, China

Abstract: Based on a lot of numerical solutions to the problems of the thermal non-Newtonian elastohydrodynamic lubrication and some fatigue tests with rollers, the lubrication factor of involute spur gears (called gear for short) is investigated. The results suggest that gear lubrication effects bear close relations to a dimensionless parameter D which is synthetically determined by gearing rotational speed, load, material, dimension and lubricant viscosity. When D≤8, the gear fatigue life increases as the lubricant viscosity is increased; When D＞8, however, the life decreases with the viscosity addition, which is in marked contrast to the lubrication factor ZL recommended by the International Standard for Computing Cylindrical Gear Strength. At the end, a set of formulae for calculating gear lubrication factors suitable for different working conditions are advanced.