2018 National Bearing Industry Quality Conference

Thrust ball bearings, also known as thrust bearings, consist of a row of steel balls (with cage), a shaft ring (tightly fitted with the shaft) and a race (with a clearance from the shaft and tightly fitted with the housing bore). Steel ball is rotating between the shaft ring and the race. It can only withstand axial loads in one direction and cannot withstand radial loads. Since the axial load is evenly distributed on each steel ball, the load capacity is large; however, when working, the temperature rise is large, and the allowed limit speed is low.

Thrust ball bearings can not limit the radial movement of the shaft or casing, but can limit the axial movement of the shaft and casing in one direction. Therefore, such bearings are often used in conjunction with deep groove ball bearings.

When installing, the axis of the shaft and housing bore must be kept concentric, otherwise the bearing will be prematurely damaged due to stress concentration. In order to eliminate this phenomenon, a radial gap of 0.5 to 1 mm may be left between the outer diameter of the race and the hole of the outer casing. The shaft center line and the bearing support surface should be vertical, and the shaft should not be inclined or deflected. Otherwise, the bearing will be damaged prematurely due to uneven load distribution. In order to eliminate the inclination of the bearing axis, the support surface of the race can be padded with an elastic material such as an oil-resistant rubber, leather, or thrust ball bearing with a spherical seat.

Thrust ball bearings are mainly used in automobiles, machine tools, oil rigs, iron and steel machinery industries.