Type Selection Requirements For Long Life INA Imported Bearings
Type Selection Requirements For Long Life INA Imported Bearings
2021年12月11日
The Higher The Importance Of SKF Bearing, The More Careful Inspection Is Required
The Higher The Importance Of SKF Bearing, The More Careful Inspection Is Required
2021年12月11日

Precautions For Selection And Use Of FAG Imported Bearings

 

Selection of fag imported bearing model:

The bearing model is generally selected according to the service conditions and load of supporting products. Therefore, it is necessary to know whether the user’s actual load is consistent with the selected fag imported bearing. If the bearing fails to meet the use requirements, the model shall be selected as soon as possible, but there will be no problem in selecting the model unless special products. Selection of fag imported bearing clearance: when purchasing fag imported bearings, generally only the model and grade will be informed, and there are few requirements for the clearance of fag imported bearings. The business personnel must ask about the service conditions of the bearings, including the speed, temperature and matching allowance of fag imported bearings, which are directly related to the selection of fag imported bearing clearance. Generally, CM clearance is mostly used for motors with speed below 3500 rpm.

 

For example, relatively large clearance is required for high-temperature and high-speed motors. After assembly, the clearance of fag inlet bearing will be reduced due to the increase of inner hole and the reduction of outer circle. The reduction of clearance = interference × 60% (except that fag inlet bearing chamber is aluminum). For example, if the clearance before bearing assembly is 0.01mm and the interference during assembly is 0.01mm, the clearance after fag imported bearing assembly is 0.004mm. Theoretically, the noise and service life of the bearing reach the state of zero clearance, but considering the temperature rise and other problems in actual operation, the clearance of the bearing after assembly is 0.002mm-0.004mm. Selection of grease: the selection of grease is generally based on the speed, temperature resistance, noise requirements and starting torque of fag imported bearings. It is required to have a good understanding of the performance of various greases.

 

Selection of sealing type of fag imported bearing: the lubrication of fag imported bearing can be divided into oil lubrication and grease lubrication. Oil lubricated fag imported bearings are generally formal bearings, and grease lubricated fag imported bearings are generally sealed with dust covers or rubber seals. The dust cover is suitable for parts with high temperature or good service environment. The seals are divided into contact seal and non-contact seal. The contact seal has good dust-proof performance but large starting torque, and the non-contact seal has small starting torque, but the sealing performance is not as good as the contact seal.

Precautions For Selection And Use Of FAG Imported Bearings
Selection and control of tolerance of shaft and fag inlet bearing chamber:

The bearing shall rotate flexibly without blocking feeling after being pressed into fag inlet bearing. If there is obvious inflexible rotation, it indicates that the size of the shaft is too large and the tolerance should be reduced. If the fag imported bearing is pressed into the shaft and rotates by hand with an obvious “rusty” feeling, it may be that the tolerance of the shaft is too large or the roundness of the shaft is not good. Therefore, the roundness should also be controlled when controlling the tolerance of shaft and fag inlet bearing chamber.

 

Assembly method of fag imported bearing: because fag imported bearing is a high-precision product, if it is improperly assembled, it is easy to damage the fag imported bearing channel, resulting in bearing damage. Fag imported bearing shall be equipped with a special mold during assembly, and can not be knocked at will. When pressing the shaft, only a small ring can be stressed, and when pressing a large ring, only a large ring can be stressed. Pneumatic or hydraulic pressure is required during assembly. During press assembly, the upper and lower molds shall be outside the horizontal state. If there is inclination, the bearing channel will be damaged due to stress, resulting in conduction sound of fag inlet bearing.

 

Prevention of assembly foreign matters: when fag inlet bearing is installed on the rotor for dynamic balance, it is easy to enter the iron filings generated during dynamic balance into fag inlet bearing, so dynamic balance is performed before bearing installation. During assembly, apply some oil or grease in the fag inlet bearing chamber for lubrication, but it is often difficult for the operator to control the amount. If more oil or grease is accumulated in the fag inlet bearing chamber, it is easy to enter the bearing along the shaft when the fag inlet bearing rotates. The bearing chamber shall not be coated with oil or grease. If it must be coated, it shall be controlled and there shall be no accumulation in the fag inlet bearing chamber.

 

Prevention of paint rust: paint rust is often found in sealed motors. The sound of the motor is very good during assembly, but after it has been placed in the warehouse for some time, the abnormal noise of the motor becomes very large, and there is serious rust when removing fag imported bearings. In the past, many manufacturers thought it was the bearing problem. Now the motor factory has realized that the main problem is the insulating paint. This problem is mainly because the acidic substances volatilized from the insulating paint form corrosive substances at a certain temperature and humidity, which corrodes the fag inlet bearing channel and leads to the damage of fag inlet bearing. At present, only good insulating paint can be selected and assembled after drying and ventilation for a period of time. The service life of fag imported bearings is closely related to manufacturing, assembly and use. It must be done well in each link in order to make the bearings in the running state, so as to prolong the service life of fag imported bearings.