The Maintenance-Free bearings is a component supporting the shaft, which is used to guide the rotational movement of the shaft and bear the load transmitted from the shaft to the frame. Bearings are widely used and strictly required accessory parts and basic parts in the machinery industry. They are the supporting elements for the rotating shafts or movable parts of various machines, and they are also the supporting elements that rely on the rolling of rolling elements to realize the rotation of the host. People are called mechanical joints.

Bearings have become the main supporting form of modern mechanical vehicles and are widely used. Due to the wide range of use, the variety and complexity of bearing varieties are determined. The strict requirements determine the importance of bearing quality and performance. Bearing manufacturing is a kind of precision basic parts manufacturing. Its accuracy is measured by 0.001 mm, while the manufacturing tolerance of ordinary mechanical parts is generally only 0.01 mm. The noise and vibration of the motor largely depend on the quality of the bearing; the swing difference and temperature rise of the high-precision machine tool spindle are closely related to the quality of the bearing; the performance of the bearing in the rotating device of the communication satellite directly affects its communication effect; aerospace The failure of key bearings in aviation will cause serious accidents. In short, the accuracy, performance, life, reliability and various economic indicators of mainframes in various fields such as industry, agriculture, national defense, science and technology, and household appliances are closely related to the bearing, and the development of the bearing industry is also related It depends on the manufacturing level of China's major technical equipment and the export capacity of machinery and equipment. Bearings are essential and indispensable basic components in contemporary machinery and vehicles. Although it has only a history of more than a hundred years, because it is related to the national economy and people’s livelihood, countries around the world spare no effort to develop their own bearing industry. With superb modern science and technology, there are more than 100,000 types of bearings produced, with excellent quality and superior performance. The development of machinery industry and other industries has made outstanding contributions to the progress of human society.

Rolling bearings are mass-produced in a special factory, which can guarantee the quality, and are very convenient in use, installation, and replacement. Therefore, they are widely used in machines operating under medium speed, medium load and general working conditions. Under special working conditions, such as high speed, heavy load, precision, high temperature, low temperature, anti-corrosion, anti-magnetic, miniature, extra large and other occasions, rolling bearings can also be used, but it is necessary to adopt some special features in terms of structure, materials, processing technology, heat treatment, etc. Technical measures. Rolling Slotted Bearings have been standardized and mass-produced by bearing factories, so the cost is low. Rolling bearings have been widely used in industry. The main task of the user is to be familiar with the standard and select it correctly.