As an indispensable and important power provider in people's production and life, many motors will generate severe heat during use, but they often do n’t know how to solve them, and even more seriously do not know why. The heat generated by the motor should be grasped first in the use of the motor.
Let's take a look at the common reasons why the motor is very hot.
1
The air gap between the stator and the rotor of the motor is very small, which easily leads to collision between the stator and the rotor.
In medium and small motors, the air gap is generally 0.2mm to 1.5mm. When the air gap is large, a large excitation current is required, which affects the power factor of the motor; if the air gap is too small, the rotor may be subject to friction or collision. Generally, due to the severe bearing misalignment and the wear and deformation of the inner holes of the end cover, the different shaft centers of the machine base, end cover and rotor cause sweeping, which can easily cause the motor to heat up or even burn. If the bearing is found to be worn, it should be replaced in time. Replace the end cap or brush plating. The simpler method is to insert an end cap.
2
The abnormal vibration or noise of the motor easily causes the motor to heat up
This situation belongs to the vibration caused by the motor itself, most of which are due to the poor dynamic balance of the rotor, as well as poor bearings, curved shafts, different shaft centers of the end caps, bases, and rotors, loose fasteners, or uneven installation foundations of the motors and incomplete installation The cause may also be transmitted from the mechanical end, which should be excluded according to the specific situation.
3
The abnormal operation of the bearing will definitely cause the motor to heat up. Whether the bearing works normally can be judged by hearing and temperature experience.
Use the hand or a thermometer to test the bearing end to determine whether the temperature is within the normal range. You can also use a listening rod (copper rod) to contact the bearing box. If you hear an impact, it means that one or more balls may be crushed. A snoring sound means that the bearing has insufficient lubricant. The motor should be changed once every 3,000 hours to 5,000 hours.
