Deep groove ball bearing is a combination of supporting shaft rotation. Its rings and rollers are precision machined. Before bearing leaving factory, in order to protect the surface of raceway and rolling body from rust, anti-rust oil or anti-rust grease is injected between raceway and rolling body. Therefore, the bearings should be cleaned before installation. Bearings sealed with rust-proof oil can be cleaned directly with gasoline or kerosene; if heavy oil or rust-proof grease is used for rust-proof, light mineral oil, such as 10# engine oil or transformer oil, must be heated to dissolve and cool the grease before cleaning with gasoline or kerosene. Bearings with dust proof caps or sealing rings on both sides have been added grease before they leave the factory, so they need not be cleaned again during installation. Bearings coated with lubricating and rust-proof grease need not be cleaned during installation. In the process of cleaning and installation, foreign bodies should be strictly prevented from falling into the bearing, because micro-abrasive particles will cause wear and tear between the rolling body and raceway, increase noise and vibration.
There are two main ways to assemble and disassemble bearings. Firstly, the interference ring is pressed into the shaft or into the bearing seat hole; secondly, the inner diameter of the bearing is expanded by heating the bearing, or the outer diameter of the bearing is reduced by cooling the bearing, so that the bearing can be easily mounted on the shaft or pushed into the seat hole. When pressure is applied, the mechanical or hydraulic force acts directly on the ring to be assembled and disassembled through a special device, and the loading and unloading force is never allowed to be transmitted through the rolling body. Otherwise, it will cause indentation on the surface of raceway and rolling body, increase noise and vibration and cause damage. If heating or cooling method is used for assembly and disassemble, the heating temperature or cooling temperature should be strictly controlled. Because the strength of the bearing working surface is affected by the metal structure of the metal surface, too high temperature will cause tempering effect, too low temperature will cause the cellular transformation of the metal surface. Usually the heating temperature should not exceed 100℃, and the lowest cooling temperature should not be lower than minus 50℃. At the same time, uniform heating should be considered.
Practice has proved that improper installation of bearings is one of the reasons leading to premature damage of bearings. It is very difficult to assemble and disassemble rings with interference. Therefore, in the design of support, it is necessary to consider how to assemble and disassemble bearings and how to make them easy to assemble and disassemble. Special equipment is often needed for assembling and disassembling large bearings of heavy machinery. If high-pressure oil is used for disassemble, the oil pipeline, pipeline and pump should be designed accordingly. This paper simply introduces some common devices and methods used in assembling and disassembling medium and small bearings. The process of bearing installation is also the process of bearing clearance adjustment. Therefore, some methods of clearance adjustment should be introduced when introducing the installation method.