單排四點接觸球式回轉支承由兩個座圈組成，結構緊湊，重量輕，鋼球與圓弧滾道四點接觸，能同時承受軸向力，徑向力和傾翻力矩，回轉式輸送機，焊接操作機，中小型起重機和挖掘機等工程機械均可選用。

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.