Summary of plain bearings

2021-09-06 11:33:57

Spherical plain bearing is a kind of spherical plain bearing. Its sliding contact surface is an inner spherical surface and an outer spherical surface. It can rotate and swing at any angle during movement. It is made by a variety of special processing methods such as surface phosphating, cratering, pad inlay, spraying and so on. Articulated bearing has the characteristics of large load capacity, impact resistance, corrosion resistance, wear resistance, self-aligning and good lubrication.

The structure of plain bearing is simpler than that of rolling bearing. It is mainly composed of an inner ring with outer sphere and an outer ring with inner sphere. The plain bearing is generally used for low-speed swing motion (i.e. angular motion). Because the sliding surface is spherical, it can also make inclined motion (i.e. centering motion) within a certain angle range. It can still work normally when the non concentricity between the support shaft and the shaft shell hole is large.

1、 Characteristics

The plain bearing can bear large load. According to its different types and structures, it can bear radial load, axial load or combined radial and axial load at the same time. Because the outer spherical surface of the inner ring is inlaid with composite materials, the bearing can produce self lubrication in operation. It is generally used for low-speed swing movement and low-speed rotation. It can also make inclined movement within a certain angle range. It can still work normally when the non concentricity between the support shaft and the shaft shell hole is large. Self lubricating plain bearings are used in water conservancy, professional machinery and other industries.

2、 Composition

The plain bearing is mainly composed 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 a rolling friction pair.

3、 Performance

Because the structural form and working mechanism of articulated bearing are completely different from that of rolling bearing, articulated bearing has its own technical characteristics and maintenance requirements.

4、 Loading and unloading

The loading and unloading of plain bearings shall follow the following principle, that is, the force applied by assembly and disassembly cannot be directly transmitted through the spherical sliding surface. In addition, auxiliary loading and unloading tools, such as sleeves and disassemblers, shall be used to directly and evenly apply the external loading and unloading force to the matched ferrule, or no-load loading and unloading shall be carried out by auxiliary methods such as heating.

5、 Installation

When assembling the plain bearing series, it is necessary to pay special attention to the position of the split surface of the outer ring. In order to avoid the load directly acting on the dividing surface, it is necessary to maintain the dividing surface at right angles to the conforming direction.

6、 Lubrication

When the applied load and the speed generated by swing motion are very small, the oil fed articulated bearing can be operated without lubrication. However, in general, grease must be replenished regularly. During the initial installation and operation, it is recommended that the lubrication cycle should be appropriately shortened.

Oil free plain bearings can be used without lubrication. However, if lithium soap based grease is added before operation, the service life of spherical bearings can be extended. If grease is injected into the space around the bearing, the joint bearing will be more effective in preventing the invasion of dust and foreign matters.