中文摘要：

介绍了四点接触球转盘轴承中产生摩擦的各个因素，在此基础上给出了球与沟道间摩擦力矩的理论计算公式，分析了初始接触角、沟曲率半径系数、钢球直径、游隙对四点接触球转盘轴承钢球与沟道间摩擦力矩的影响，认为四点接触球转盘轴承的初始接触角为50°-60°，沟曲率半径系数为0．53～0．54，游隙为-0．01～0．01mm，同时选择较小的钢球直径，有利于减小轴承的摩擦力矩，降低轴承的发热量，提高轴承的使用寿命。

英文摘要：

The factors bringing about the friction are introduced in four point contact ball slewing bearings, and the theoretical calculation formulas of the friction torque between the balls and the raceways are given. The effects of the initial contact angle, raceway curvature coefficient, ball diameter and clearance on friction torque between the balls and the raceways are analyzed. It is found that in order to decrease the friction torque and heat, and improve the life, the parameters of the bearings should be selected as following： the initial contact angle of four point contact ball slewing bearings 50°- 60°, raceway curvature radius coefficient 0.53 - 0.54 , clearance - 0.01 - 0.01mm and smaller ball diameter.