Materials and functions of water pump bearing parts
The water pump bearing is a vital component in the water pump. Its main function is to support the rotation of the pump shaft, reduce the friction coefficient during the rotation process, and ensure the rotation accuracy and stability of the pump shaft. The materials and functions of the water pump bearing parts can be elaborated in detail from the following aspects:
1. Materials of water pump bearing parts
The material selection of water pump bearings has a vital impact on its performance and life. Common bearing materials are mainly divided into two categories: metal materials and non-metallic materials.
1. Metal materials
Bearing alloy (Babbitt alloy or white alloy): The main alloy components are tin, lead, antimony, and copper, which are used to improve the strength and hardness of the alloy. Babbitt alloys can be divided into tin-based alloys and lead-based alloys according to standards. Among them, tin-based alloys have higher strength and hardness and better corrosion resistance, so they are usually preferred. Commonly used grades include ZSnSb11Cu6, ZSnSb8Cu4, etc. However, Babbitt alloys have a low melting point and are suitable for use in working conditions below 150°C.
Wear-resistant cast iron: It has good wear resistance and mechanical strength, and is suitable for some occasions with high requirements for wear resistance.
Copper-based and aluminum-based alloys: Copper-based alloys have high thermal conductivity and wear resistance, and excellent processability and lubricity. Commonly used copper-based alloys include brass (with copper and antimony as the main components), bronze (with copper and tin as the main components) and copper-lead alloy (also known as lead bronze). These alloys are suitable for bearings under different speed and load conditions.
2. Non-metallic materials
Polytetrafluoroethylene: It has good self-lubricating properties and high thermal stability, low friction coefficient, does not absorb water, is non-sticky, and is non-flammable. It can be used at -180~250℃. However, its linear expansion coefficient is large, its dimensional stability is poor, and its thermal conductivity is relatively low.
Graphite: It is a good self-lubricating material that is easy to process and becomes smoother with grinding. However, its mechanical properties are poor, and its impact resistance and load bearing capacity are limited. It is only suitable for light load occasions. Its mechanical properties and operating temperature range can be improved by impregnation treatment (such as impregnation with babbitt alloy, copper alloy or antimony alloy).
Rubber: It has good elasticity and vibration absorption, but poor thermal conductivity, difficult processing, and limited operating temperature (generally below 65°C). It requires circulating water lubrication and cooling, so it is rarely used in water pump bearings.
Silicon carbide: It is a new type of artificially synthesized inorganic non-metallic material with extremely high hardness, chemical corrosion resistance, wear resistance, high temperature resistance and other excellent properties. It is often used as a friction pair material for sliding bearings and mechanical seals, and is widely used in petroleum, metallurgy, chemical industry and other fields.
2. The role of water pump bearing parts
Support function: The water pump bearing provides stable support for the pump shaft through the mutual cooperation of its inner and outer rings and rolling elements (or sliding surfaces), ensuring that the pump shaft can rotate according to the predetermined trajectory.
Reduce friction: The lubrication system and material design inside the bearing can significantly reduce the friction coefficient during the rotation of the pump shaft, thereby reducing energy loss and wear.
Ensure rotation accuracy: High-precision bearing design and manufacturing can ensure that the pump shaft maintains stable rotation accuracy during rotation, which is crucial to the performance and efficiency of the water pump.
Bearing load: The bearing needs to bear various forces and moments generated by the pump shaft and liquid flow to ensure that the pump can operate stably and meet working requirements.
