Source: China Bearing Network Time: 2018-03-13

The use and selection of motor bearings First, the choice of bearing type: the bearing type is usually selected by the user's technical staff based on the operating conditions of the supporting products and the acceptance of the load. The business personnel first know whether the user's practical load can match the selected bearing. Consistent; if the bearing does not meet the operational requirements; should promptly advocate the type of customer reorganization; but unless the special product is usually not a problem in the selection type.
Second, the bearing should pay attention to the use of the bearing in the machine is mainly to support and reduce the friction; so the bearing accuracy, noise, etc. are directly related to the use of machinery and life. But business people often meet some customers That is to say, the power of the best bearing or imported bearing is not high; this is related to the application and selection of the bearing. Some people may say that "the use and selection of the bearing is the user's business; I only want the user to sell me." "But as a qualified salesman, besides knowing the common sense of the product itself, you must know the use of the product; that is, the sale of the physician type; select the best matching bearing according to the function and application conditions of the user's accessory products. This is the current world. The professional production and sale prevailing in major companies; this method has also played an outstanding role in the implementation of the People's Group.
1. Selection of bearing clearance: When purchasing bearings, users usually only report the type and grade of the bearing; there is little demand for the clearance of the bearing; it is necessary for the business personnel to ask about the operating conditions of the bearing, the rotational speed of the bearing, Temperature and cooperation are directly related to the selection of bearing clearance. Generally, most of the motors below 3500 rpm use CM clearance; for high-temperature high-speed motors, relatively large clearance is required. Bearing clearance is installed. After that, the reduction will be caused by the increase of the inner hole and the reduction of the outer circle; the reduction of the clearance = the interference amount × 60% (the bearing chamber is aluminum). The clearance before the bearing installation is 0. 01mm; The time interference is 0. 01mm; the clearance after the bearing is installed is 0. 004mm. In theory, the noise and the lifespan of the bearing at zero clearance reach the best condition; but in practice, temperature rise is considered. The problem is that the bearing has a clearance of 0. 002mm-0.004mm after installation.
The life of the bearing is closely related to the production, installation and operation; it is necessary to do it at every stage; in order to make the bearing in the best working condition; then extend the service life of the bearing.
2, the installation method of the bearing: because the bearing is a high-precision product; if the installation is not simple, it is very simple to damage the bearing channel; cause damage to the bearing. The bearing should have a special mold when installing; can not be hit at random; When the pressure is large, only the large circle is stressed. When installing, the air pressure or hydraulic pressure is required; when the press is installed, the upper and lower molds should be outside the horizontal condition; if there is a skew, the bearing channel will be affected by the force. Damage; and cause the bearing to make a sound.
The selection of bearings follows the progress and development of society; mechanization is widely used in production and in the days. Bearings are not a part of machinery; their use will be more and more extensive; To the bearing.
Due to the wide variety of types of bearings; the following will be the first to analyze the application and selection of the most widely used deep groove ball bearings. It is expected that people who know less about bearings can deepen their knowledge of bearings.
1. Selection and control of the shaft and bearing chambers: After the bearing is pressed into the bearing, it should be changed to be sensitive and unobstructed. If there is significant change, it is not sensitive; then the scale of the shaft is too large; the public service should be lowered. After pressing into the shaft, there is a significant "sand" feeling by hand; it may be that the public service of the shaft is too large or the roundness of the shaft is not good. Therefore, the roundness should be controlled when the shaft and the bearing chamber are operated. At present, many domestic manufacturers only control the public service; there is no control on the roundness.
2, the avoidance of paint rust: paint rust is characterized by multiple seals in the motor; the sound of the motor is very good when installed; but after some time in the warehouse; the abnormal noise of the motor is very large; Severe rusting appearance. Many manufacturers once thought it was a bearing problem; through our constant publicity; now the motor factory has realized that it is the primary problem of insulating varnish. The problem is mainly due to the acidic substance evaporated from the insulating varnish. Corrosive substances are formed under temperature and humidity; the bearing channel is corroded and the bearing is damaged. The problem can only be selected from good insulating paint; and it is installed after drying for a while.
3, the selection of grease: the selection of grease is usually based on the bearing speed, temperature resistance, noise demand and starting torque, etc.; demand business personnel on the function of various greases are well known.
4, the choice of bearing seal type: the smoothness of the bearing can be divided into oil smooth and grease smooth. Oil smooth bearing is usually the choice of bearing; grease smooth bearing is usually sealed with dust cover or rubber seal. Dust cover is suitable for high temperature or The use of the environment is good; the seal is divided into two types: touch seal and non-touch seal; touch seal has good dustproof function but large starting torque; non-connected seal starting torque.
5. Avoidance of installing foreign objects: When the bearing is mounted on the rotor to make dynamic balance, it is very simple to insert the iron filings that occur during dynamic balancing into the bearing; therefore, it is best to balance the load before loading the bearings. Some manufacturers are convenient for installation; Apply some oil or grease to the bearing chamber to smooth the effect; but it is often difficult for the operator to control the amount; if oil or grease accumulates in the bearing chamber; it is very easy to enter the bearing along the shaft when the bearing changes. The best part of the bearing chamber is not to apply oil or grease; if it is not painted, it must be handled without accumulation in the bearing chamber.