Radial spherical plain bearings feature a simpler construction than rolling bearings, primarily comprising an inner ring with an external spherical surface and an outer ring with an internal spherical surface. Typically employed for low-speed oscillating motion (i.e., angular motion), these bearings can also accommodate tilting motion (i.e., self-aligning motion) within a certain angular range due to their spherical sliding surfaces. They maintain reliable operation even when significant misalignment exists between the shaft and housing bore.

Characteristics

Spherical plain bearings can withstand substantial loads. Depending on their type and construction, they can bear radial loads, axial loads, or combined radial and axial loads. The outer spherical surface of the inner ring is fitted with composite materials, enabling self-lubrication during operation. Typically employed for low-speed oscillating motions and rotations, they also permit angular deflection within specified limits. They maintain functionality even when significant misalignment exists between the support shaft and housing bore. Self-lubricating spherical plain bearings find application in hydraulic systems, specialised machinery, and related industries.

Applications

Self-lubricating spherical plain bearings

Spherical plain bearings find extensive application in engineering hydraulic cylinders, forging presses, construction machinery, automation equipment, automotive shock absorbers, hydraulic machinery, and related sectors. These bearings constitute spherical sliding bearings, with the basic configuration comprising inner and outer rings featuring spherical sliding contact surfaces. Depending on their structure and type, they can accommodate radial loads, axial loads, or combined radial and axial loads acting simultaneously.

Owing to their large spherical sliding contact area and significant tilt angle, coupled with specialised surface treatments such as phosphating, zinc plating, chrome plating, or the application of linings, inserts, and coatings to the outer sliding surfaces, they exhibit substantial load-bearing capacity and impact resistance. These bearings also feature corrosion resistance, wear resistance, self-aligning capability, good lubrication or self-lubrication without lubricant contamination, and can operate normally even with misalignment during installation. Consequently, spherical plain bearings are widely employed in low-speed oscillating, tilting, and rotational motions.

Composition

A spherical plain bearing primarily consists of an outer ring and an inner ring. The inner spherical surface of the outer ring and the outer spherical surface of the inner ring form the rolling friction pair.