The bushing is an accessory used outside the mechanical parts to achieve sealing, wear protection, etc., and refers to the ring sleeve that acts as a gasket. In the field of valve application, the bushing is inside the valve cover, and corrosion-resistant materials such as polytetrafluoroethylene or graphite are generally used for sealing.
In the moving parts, the wear of the parts is caused by long-term friction. When the gap between the shaft and the hole is worn to a certain extent, the parts must be replaced. Therefore, the designer chooses the one with 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 seat. When the bushing or bushing is worn to a certain extent, it can be replaced, which can save the cost of replacing the shaft or seat. Generally speaking, the bushing and seat are made of Interference fit, and clearance fit with the shaft, because it is inevitable to wear anyway, it can only prolong the life, and the shaft parts are relatively easy to process; there are also some new designers who do not like this design. It increases the cost during manufacturing, but after a period of use, it is still necessary to modify it according to this method during maintenance, but the modification will easily cause the accuracy of the equipment to decrease. The reason is very simple, and the secondary processing cannot guarantee the position of the center of the seat hole. In addition, the shaft sleeve is used to replace the rolling bearing (in fact, the shaft sleeve is also a kind of sliding bearing) in some places with low speed, high radial load and high clearance requirements (such as camshaft). The material requires low hardness and resistance Grinding, the inner hole of the shaft sleeve is ground and scraped to achieve high matching accuracy. There must be an oil groove for lubricating oil on the inner wall. The lubrication of the shaft sleeve is very important. If dry grinding, the shaft and shaft sleeve will soon be scrapped. Recommended here Scrape the inner hole wall of the bushing during installation, so that many small pits can be left. The enhanced lubrication bushing and bushing are selected according to different industrial and mining conditions. Different models. The most important conditions are: pressure, velocity, pressure-velocity product, lubrication state, load nature. Bushing quick, easy and optimal automatic selection is included.
Wraps the stem, and if it wears out, it can be easily replaced. If the bushing is not used, it is the part that is replaced when it wears out. So the replacement is to replace the bushing (when designing, the hardness of the bushing is reduced to make it a wear-bearing part in the friction pair). Because of its convenient processing, low replacement cost and easy replacement. Of course, there are guiding functions, etc., which are secondary.