QJBY is a professional sliding bearings manufacturer and supplier in China. 

A slide bearing or plain bearing, is the simplest type of bearing, comprising just a bearing surface and no rolling elements. Therefore, the journal (i.e., the part of the shaft in contact with the bearing) slides over the bearing surface. The simplest example of a plain bearing is a shaft rotating in a hole. A simple linear bearing can be a pair of flat surfaces designed to allow motion or the ways on the bed of a lathe.

Sliding bearings work under sliding friction. The sliding bearings work smoothly and reliably without noise. Under liquid lubrication conditions, the sliding surface is separated by the lubricating oil without direct contact, the friction loss and surface wear can be greatly reduced, and the oil film also has a certain vibration absorbing capability. However, the starting friction resistance is large.

The design of a sliding bearing depend on the type of motion the bearing must provide. The three types of motions possible are:

Journal (friction, radial or rotary) bearing: This is the most common type of plain bearing. It is simply a shaft rotating in a hole. 

Linear bearing: This bearing provides linear motions. It may take the form of a circular bearing and shaft or any other two mating surfaces.

Thrust bearing: A thrust bearing provides a bearing surface for forces acting axial to the shaft. One example is a propeller shaft.

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