Friction is the force that resists the relative motion of two surfaces in contact with each other. When bush bearings are in operation, friction is generated between the bearing surface and the mating surface it comes into contact with, typically a shaft or a housing. This friction can be caused by various factors such as the speed of rotation, load applied, and the condition of the mating surface. Over time, this friction can result in wear in the plastic material of the bush bearing.
Wear in plastic bush bearings can occur in different forms. One common type of wear is adhesive wear, also known as galling. Adhesive wear happens when the surfaces of the bearing and the mating surface adhere to each other and then separate, causing small fragments of material to be removed from the bearing surface. This can result in surface roughness, loss of material, and ultimately, a decrease in the bearing's performance.
Another type of wear in plastic bush bearings is abrasive wear. Abrasive wear occurs when hard particles or debris come into contact with the bearing surface, leading to the removal of material through mechanical abrasion. This can be caused by contaminants in the operating environment or particles that are introduced into the system during operation, such as dust, dirt, or debris. Abrasive wear can result in increased friction, reduced clearance, and premature failure of the bush bearing.
Fatigue wear is another form of wear that can occur in plastic bush bearings. Fatigue wear is caused by repeated loading and unloading cycles, which can lead to localized stress concentrations and material fatigue. This can result in the formation of cracks, fractures, and ultimately, material failure.
The material properties of the plastic used in bush bearings can also influence wear. Factors such as the type of plastic, its composition, and its mechanical properties can affect the wear resistance of the bearing. For instance, materials with lower hardness or lower melting points are more susceptible to wear caused by friction. Additionally, the presence of fillers or reinforcements in the plastic material can also impact wear resistance.
To mitigate wear in plastic bush bearings caused by friction, proper lubrication and maintenance are critical. Lubrication can reduce friction between the bearing and mating surfaces, minimizing wear. The choice of lubricant should be compatible with the plastic material used in the bush bearing and the operating conditions of the application. Regular inspection and cleaning of the bearing and mating surfaces can also prevent the buildup of contaminants and debris, reducing the risk of abrasive wear.