Maintenance-free spherical plain bearings are used where there are particular requirements for operating life or where bearings with a metallic sliding contact surface are not suitable for lubrication reasons, e.g. under unilateral load. Spherical plain bearings allow spatial adjustment movements and, depending on the bearing type (radial, angular contact or axial spherical plain bearing), can support, radial, combined or axial loads.
Maintenance-free spherical plain bearings have special sliding layers based on PTFE (polytetrafluoroethylene). In descending order of performance, these are:
These materials form the slideway of the outer ring or shaft locating washer. They transmit the forces occurring and provide lubrication – the bearings must not be lubricated by any other means.
Radial spherical plain bearings
Radial spherical plain bearings comprise inner and outer rings with maintenance-free sliding layers of ELGOGLIDE®, PTFE composite or PTFE-bronze film. They can support slight axial forces as well as radial forces and are suitable for alternating dynamic loads. Sealed spherical plain bearings are protected against contamination and spray water by lip seals. Large spherical plain bearings of d = 320 mm and above belong to the premium grade X-life.
Angular contact spherical plain bearings
Angular contact spherical plain bearings comprise inner and outer rings with ELGOGLIDE®. They can support higher axial forces as well as radial forces and are suitable for alternating dynamic loads.
Axial spherical plain bearings
Axial spherical plain bearings comprise shaft and housing locating washers with ELGOGLIDE®. They are preferably used to support axial forces and are suitable as support or base bearings. Large spherical plain bearings of d = 220 mm and above belong to the premium grade X-life.
Cylindrical plain bushes
Cylindrical plain bushes comprise a steel bush with ELGOGLIDE®. They permit not only swivel movements but also axial movements and can support higher forces than conventional plain bearings. |
