You are in our Global Site


Plain Bearing

The spherical plain bearing is a kind of spherical sliding bearing. Its sliding contact surface is an inner spherical surface and an outer spherical surface. It can rotate and swing at any angle during the movement. It is made of various special processing methods such as surface phosphating, frying(stress fracture opening), padding, spraying, etc. The spherical plain bearing has the characteristics of large load capacity, impact resistance, corrosion resistance, wear resistance, self-aligning and good lubrication.

Radial Spherical Plain Bearings

It is also known as radial joint bearings. Radial Spherical Plain Bearings can withstand radial loads and small axial loads in either direction.

Axial Spherical Plain Bearings

It is also known as thrust joint bearings. Both the shaft washer and the seat washer are hardened bearing steel; the seat ring has oil grooves and oil holes. Axial spherical plain bearings can withstand axial load or combined load in one direction (at this time, the radial load value should not be greater than 0.5 times the axial load value).

Angular Contact Spherical Plain Bearings

It is also known as angular contact joint bearings. The inner and outer rings are all hardened bearing steel, and the outer ring has oil grooves and oil holes. Angular contact spherical plain bearings can withstand radial loads and axial (combined) loads in one direction.

Self-lubricating Bearing

It is also known as bushing. Bushings are accessories that are used outside of mechanical parts to achieve sealing, wear protection, etc., and refer to the ring sleeve that acts as a gasket. In the field of valve applications, the bushing is inside the valve cover, and corrosion-resistant materials such as PTFE or graphite are usually used to make it. Bushings are generally used for sealing.

Plain Bearing Definition

Sliding bearing is a bearing that works under sliding friction. Sliding bearings work smoothly, reliably and without noise. Under liquid lubrication conditions, the sliding surfaces are separated by lubricating oil without direct contact, which can greatly reduce friction loss and surface wear, and the oil film also has a certain vibration-absorbing ability, but the starting friction resistance is large. The part of the shaft supported by the bearing is called the journal, and the part that matches the journal is called the bearing bush. In order to improve the friction properties of the bearing surface, the layer of anti-friction material cast on its inner surface is called a bearing lining. The materials of the bearing shell and bearing bush are collectively referred to as sliding bearing materials. Sliding bearing is generally applied in high-speed and light-load conditions.

The Application of Spherical Plain Bearing

Spherical plain bearings are widely used in engineering hydraulic cylinders, forging machine tools, engineering machinery, automation equipment, automotive shock absorbers, water conservancy machinery and other industries. The spherical plain bearing is a spherical sliding bearing, and the basic type is composed of inner and outer rings with spherical sliding spherical contact surfaces. Depending on its structure and type, it can bear radial load, axial load, or combined radial and axial loads at the same time.

The spherical sliding contact area of the spherical plain bearing and the inclination angle are large, and most of the spherical plain bearings adopt special processing methods, such as surface phosphating, galvanizing, chrome plating or outer sliding surface lining, padding, spraying, etc., therefore, it has a large load capacity and impact resistance, and has the characteristics of corrosion resistance, wear resistance, self-alignment, good lubrication or self-lubricating without lubrication and dirt pollution, and can work normally even if the installation is misplaced. Therefore, spherical plain bearings are widely used for low-speed oscillating motion, tilting motion and rotational motion.

The Features of Spherical Plain Bearing


When assembling the spherical plain bearing series, it is necessary to pay special attention to the position of the outer ring dividing surface. In order to prevent the load from directly acting on the dividing surface, the dividing surface should be maintained at right angles to the matching direction.

Loading and unloading:

The assembly and disassembly of spherical plain bearings should follow the following principles, that is, the force exerted by assembly and disassembly cannot be transmitted directly through the spherical sliding surface. In addition, auxiliary loading and unloading tools, such as sleeves, disassemblers, etc., should be used to directly and uniformly apply the loading and unloading force exerted by the outside to the matching ferrule, or use auxiliary methods such as heating for unloaded loading and unloading.

Operating temperature:

The allowable working temperature of the spherical plain bearing is mainly determined by the matching materials between the bearing sliding surfaces, especially the plastic sliding surface of the self-lubricating spherical plain bearing, its load-carrying capacity will decrease at high temperature. For example, when the sliding surface material of lubricated spherical plain bearing is steel/steel, the allowable working temperature depends on the allowable working temperature of the lubricant. But for all lubricated and self-lubricating spherical plain bearings, they can be used in the temperature range of -30℃~+80℃, and maintain the correct bearing capacity.

Custom Bearings From THB Bearings

Any questions or concerns about types of industrial bearings and their uses, you can ask here.
As a specialized solutions provider of bearing technology, THB Bearings team member will get back to you within 24 hours for your bearing design, analysis and engineering services.
Contact THB Bearings to get more info about all types of custom bearing products and service!
select files