Plain bearings / Spherical plain bearings Info

Plain bearings and spherical plain bearings are used to reduce friction between moving components. 
Plain bearings have a simpler design and consist of two sliding surfaces that move against one another, thereby reducing friction. The sliding surfaces are either made of self-lubricating material or must be treated with lubricants.
Spherical plain bearings, on the other hand, reduce friction via the sliding surface of the hollow spherical outer ring and the bulbous inner ring. Thanks to their design, spherical plain bearings can evenly absorb high loads and allow movement in various directions.

Further information about our plain bearings / spherical plain bearings:

Plain and spherical plain bearings are used alongside roller bearings as machine components for guiding moving parts relative to one another. Unlike spherical plain bearings and roller bearings, plain bearings are simpler in design yet can still withstand high forces. 

In roller bearings, the shaft is supported by rolling elements that rotate with it, whereas in plain and spherical plain bearings, the two components moving relative to one another are in direct contact. In plain bearings, frictional resistance arises from the shaft sliding within the bearing bush; in spherical plain bearings, the inner ring slides on the outer ring. Depending on the material, this friction necessitates lubrication between the sliding surfaces.

Plain bearings are available as cylindrical bushings in the form of sleeves, with or without a flange, as well as in the form of thrust washers or blanks. They are further categorised into plain bearings that are rolled, turned from solid material, or manufactured using various forming processes.

Cylindrical bushings can be used in applications involving radial forces, whilst bushings with a flange can accommodate both radial and axial forces. 

Plain bearings are either maintenance-free (self-lubricating) or require maintenance (lubrication required). They are available in many different materials, such as bronze, sintered bronze or synthetic material, as well as composite bearings made from metal-polymer or PTFE fibre composites.

Spherical plain bearings are ready-to-install, standardised machine components used in swivelling, tilting and rotational movements involving static or dynamic forces and low speeds. 

Depending on the load on the bearing, different types of spherical plain bearings are used: radial spherical plain bearings for purely radial loads, axial spherical plain bearings for purely axial loads, and angular contact spherical plain bearings, which can accommodate both radial and axial loads.

Spherical plain bearings consist of a hollow spherical outer ring and a bulbous inner ring (ball joint). The main differences between the various series are the overall dimensions and the bearing surface pairing (steel/steel, steel/brass, stainless steel/PTFE, etc.). The different bearing surface pairings determine whether a spherical plain bearing is maintenance-free or requires maintenance.

Rod ends are spherical bearing units and consist of an internal or external thread which terminates in a rod end (eye), where a spherical bearing is fitted.

The main area of application for rod ends is in hydraulic and pneumatic cylinders. As with spherical plain bearings, rod ends are available in various materials; some are maintenance-free, whilst others require lubrication.