What is the working principle of planar thrust bearings?
The core working principle of planar thrust bearings is to convert axial loads into rolling friction, achieve low resistance axial positioning and force transmission through the rolling of rolling elements, and allow relative rotational motion between the shaft and the housing.
When the equipment generates axial force (thrust or pressure along the axis direction) during operation, this force will first act on the shaft ring of the bearing (a component fixed to the rotating shaft), and then be transmitted to the internal rolling elements (balls, rollers, etc.) through the shaft ring raceway, and then transmitted to the seat ring (a component fixed to the stationary shell) by the rolling elements, ultimately dispersing the axial force to the supporting structure.
When sliding friction is converted into rolling friction, when the bearing is not working, the end faces of the shaft ring and the seat ring are theoretically in surface contact, and there will be significant sliding friction when they rotate relative to each other. The presence of rolling elements transforms the contact between the shaft ring and the seat ring into a line/point contact between the rolling elements and the two ring raceways. When the shaft drives the shaft ring to rotate, the rolling elements undergo self rotation and revolution within the raceway, converting the original sliding friction into rolling friction, significantly reducing the friction coefficient (usually only 1/10~1/100 of sliding friction), thereby reducing energy loss and component wear.
The size of the axial positioning and motion constraint rolling elements and the geometric shape of the raceway are precisely designed to strictly limit the axial movement of the shaft and ensure the axial position accuracy of the shaft during rotation. Different types of planar thrust bearings (such as thrust self-aligning roller bearings) can also compensate for certain installation coaxiality errors through their own structures, avoiding early failure caused by unbalanced loads.
