单排四点接触球式回转支承由两个座圈组成，结构紧凑，重量轻，钢球与圆弧滚道四点接触，能同时承受轴向力，径向力和倾翻力矩，回转式输送机，焊接操作机，中小型起重机和挖掘机等工程机械均可选用。

The single-row four points contact ball Slewing Bearing is composed of 2 seat-rings.It features compact in design,and light in weight.The balls contact with the circular race at four points,via which the axial force,radial force and resultant moment may be born simultaneously.It may be used for slewing conveyors,welding arms and positioners,light,medium duty cranes,excavators and other engineering machines.