Material Selection of Bushings Without Lubricating Bearings
Bearing is widely used in various types of machines. Generally, when selecting bearings, lubricating bearings are often used to reduce frictions and ensure long service life. However, lubricating bearings can easily lead to leakage, which can cause pollution and equipment damage. Therefore, the use of bushings without lubricating bearings is an ideal option in many industries.
Bushings without lubricating bearings are hollow cylindrical components with two ends side opening. The function of bushings without lubricating bearing is to reduce friction and provide effective support for the component to rotate or move. In the material selection of bushings without lubricating bearings, different bearing materials are used for different working conditions, such as temperature, speed, load, vibration and corrosive environment, etc.
For bushings without lubricating bearings used in low speed and light load occasions, the bearing material that be used often is carbon graphite bronze, composite bronze, aluminum or other soft metals. Carbon graphite bronze has higher strength and hardness, excellent antifriction performance and good wear resistance, but its elasticity is relatively weak so it is not suitable for dynamic friction load and cyclic service condition. Composite bronze has good performance and better wear resistance than carbon graphite bronze. Aluminum and other soft metals are suitable for low speed and light load occasions due to their low elastic modulus and good impact resistance.
For bushings without lubricating bearings used in high speed and heavy load conditions, the bearing material should have high strength, good flexibility and wear resistance. Such materials include high-carbon high-chrome steel, cemented carbide and ceramic. High-carbon high-chrome steel with good welding performance, heat treatment performance and wear resistance is usually used to make bushings of large diameter, especially in heavy machinery. Cemented carbide has the advantages of high hardness, good wear resistance, and long service life, so it is often used in rolling, short-range linear motion, low-speed and light-load occasions, while ceramic materials have high hardness, excellent wear resistance, good thermal conductivity and self-lubrication performance, so it is often used in motion parts with high speeds and heavy loads.
In summary, the selection of bushings without lubricating bearings depends on the service conditions. When selecting the materials for bushings without lubricating bearings, the choice should be made according to the working temperature, speed, load, vibration and corrosive environment, etc. Hard materials such as high-carbon high-chrome steel, cemented carbide and ceramic are suitable for bushings used in high speed and heavy load conditions, while soft materials such as carbon graphite bronze, composite bronze, aluminum and other soft metals are suitable for bushings used in low speed and light load occasions.
