In the moving parts, the parts are worn due to long-term friction. When the clearance between the shaft and the hole wears to a certain extent, the parts must be replaced. Therefore, the designer chooses a lower hardness and better wear resistance when designing. The material is a shaft sleeve or a bushing, which can reduce the wear of the shaft and the seat. When the shaft sleeve or the bushing is worn to a certain extent, it can be replaced. This can save the cost of replacing the shaft or the seat. Generally, the bushing and the seat are used. Interference fit, and clearance fit with the shaft, because wear is unavoidable in any case, can only extend the life, and shaft parts are relatively easy to process; some new designers do not like this design, think that It is an increase in cost during manufacture, but after a period of use, it is still necessary to modify it in accordance with this method. However, the modification is likely to reduce the accuracy of the equipment. The reason is simple. Secondary processing cannot guarantee the position of the center of the seat hole.

In addition, the bushing is used to replace rolling bearings (such as camshafts) in places with low speed, high radial load and high clearance requirements (actually, the bushing is also considered as a plain bearing). The material requires low hardness and resistance Grinding, the inner hole of the shaft sleeve can be ground and scraped to achieve high matching accuracy. There must be an oil groove on the inner wall. Lubrication of the shaft sleeve is very important. If dry grinding, the shaft and shaft sleeve will be scrapped quickly. Recommended here Scrap the inner hole wall of the sleeve during installation, which can leave many small pits and enhance lubrication

1. Plain bearing bushing generally function as sliding bearings. In order to save material, the wall thickness of the sleeve is designed according to the axial load required by the bearing. Generally, cast copper and bearing alloy materials are used. The shaft sleeve is divided into open and non-open, which depends on the needs of the structure. Generally, the sleeve cannot bear axial load, or can only bear small axial load. Or add thrust bearings. The shaft is generally round.

2.Bushings generally function as linings. The shaft can be of various shapes, as is the bushing. Bushings can be used to prevent corrosion, eliminate assembly gaps, etc.

The shaft sleeve generally plays the role of axial positioning, and the end is in contact with the gear bearing and other parts under compressive stress. Sometimes the shaft must be matched with seals and other standard parts, and it is necessary to ensure that the middle part can pass through the shaft end. The shaft sleeve and seal ring can be made thin to ensure that the parts pass through.

Plain bearing bushing have different uses in different occasions, can be axially positioned, can reduce friction and vibration, and can also be used to isolate the shaft from harmful media to increase shaft life and durability.