Plain bearing is a bearing that works under sliding friction. The sliding bearing works smoothly, reliably and without noise. Under liquid lubrication conditions, the sliding surface is separated by the lubricating oil without direct contact, and the friction loss and surface wear can be greatly reduced, and the oil film also has a certain vibration absorbing capability. However, the starting friction resistance is large. The part of the shaft that is supported by the bearing is called the journal, and the part that matches the journal is called the bearing. The layer of friction reducing material cast on its inner surface in order to improve the frictional properties of the surface of the bearing pad is referred to as a bearing lining. The material of the bearing bush and bearing bushing is collectively referred to as a plain bearing material. Commonly used sliding bearing materials are bearing alloys (also known as babbitt or white alloy), wear-resistant cast iron, copper-based and aluminum-based alloys, powder metallurgy materials, plastics, rubber, hardwood and carbon-graphite, and polytetrafluoroethylene (PTFE). ), modified polyoxymethylene (POM), and the like. Sliding bearing applications are generally used under low-speed and heavy-duty conditions, or where it is difficult to maintain and fill lubricants.
A precise mechanical component that converts the sliding friction between the running shaft and the shaft seat into rolling friction, thereby reducing friction loss, is called a rolling bearing. Rolling bearings generally consist of an outer ring, an inner ring, a rolling element and a cage. The inner ring is matched with the shaft and rotates together with the shaft, and the outer ring acts to cooperate with the bearing seat to support the rolling element, and the rolling body is evenly distributed between the inner ring and the outer ring by means of the cage. The shape size and quantity directly affect the service performance and life of the rolling bearing. The cage can evenly distribute the rolling elements, prevent the rolling elements from falling off, and guide the rolling elements to rotate to provide lubrication.