Motor bearing heat damage to the motor
Although the motor seems to be relatively simple in structure, it is also very easy to cause very serious losses in mechanical failure. In the mechanical failure of the entire motor structure, the most likely failure is the bearing failure of the motor, most of which are It is a motor failure caused by the heat of the motor bearing. Once the motor bearing has a heating fault, it will cause the motor grease to melt and overflow, and the heavy oil will cause the grease to burn, which will directly lead to the burning of the motor bearing.
Maintenance of the motor bearing is one of the important contents of the overall maintenance of the motor, and it is also the most important type of motor maintenance. Regardless of the bearing used in the motor, once the bearing is damaged, it is very likely to cause the motor to fix the rotor and the rotor, and the uninterrupted operation of the motor causes the insulation of the motor coil to be burnt.
At the same time, due to the leakage of lubricating oil caused by the heat of the bearing, although the motor can operate normally, the leaked grease is likely to be immersed in the coil of the motor, causing dust and other debris to accumulate on the coil and insulating the motor.
Analysis of the causes of motor bearing heating
1 The friction between the motor bearing and the bearing cap causes the fault mainly because the motor does not suffer from the shortage of machining during the machining process of the bearing cap or the friction scratches appear in the assembly, resulting in local friction phenomenon when the motor bearing rotates. If it is a slight friction bearing, it will generate heat, but there will be no smoke. If you open the motor cover, you will find black rubbing marks on the friction.
If it is due to the eccentricity of the inner circumference of the motor bearing cap, or the scratches during assembly, it will cause serious friction in the motor bearing and emit smoke.
2 motor bearing refueling method problem Generally refueling the motor In order to prevent excessive refueling and convenience, it is usually the refueling operation of the outer side of the bearing. If the motor running time does not reach a sufficient length of time, the lubricating oil is difficult to distribute to the inside of the bearing. For high-speed operation or large motors, the bearings of the motor often heat up for this reason.
3 Damage to the motor bearing The ball of the motor bearing is not round or broken, and it has not undergone rigorous inspection after being repaired, and the outer ring of the motor bearing is corroded and broken due to the absence of the waterproof ring during the assembly process. The motor bearing is subject to frictional losses and generates heat.
4 If the motor belt is too tight or the coupling is not properly installed, the belt of the motor is too tight and the installation of the coupling is not uniform. This will cause the bearing of the motor to increase sharply due to the increased load. During the operation of the motor, if It is found that the motor does not generate heat when it is idling, and if there is a lot of heat in the loaded state, it is necessary to check whether the belt of the motor is too tight and the coupling is not flat.
5 improper assembly of motor bearings The most common motor bearing assembly is improper. For example, the bearing wear caused by the inner ring is not evenly knocked during the cold-loading process of the bearing, resulting in the loss of the original interference between the inner ring of the motor and the bearing. The amount is either the reduction of the interference and the phenomenon of running the inner ring; in the assembly process of the cover end of the motor, the cover end bearing chamber and the outer ring of the bearing are not loosely fitted due to the uniform tapping of the motor, so that the bearing appears Running the outer ring phenomenon.
6 There is foreign matter in the motor bearing chamber or the grease is not clean. For example, there is a tiny rigid substance in the bearing cage. During the operation of the motor, the bearing raceway is damaged and the temperature rises, resulting in the burning of the motor bearing.
7The motor bearing itself has some quality problems such as rusting of the raceway, excessive clearance, deformation of the cage and inflexibility of rotation.
