1. Water is sprayed in the mine roadway, after the motor is damp, the insulation drops, the flameproof surface is seriously rusted, and it continues to be used without drying.

2. The explosion-proof motor used by the scraper conveyer of the mining face is often covered with coal dust, resulting in poor heat dissipation of the motor.

3. Coal mine underground handling is not careful, causing damage to the motor fan cover and parts; Falling rock or coal rock flattens the motor hood, causing friction between fan and hood; The coal stone falls into the wind hood of the motor, and the fan is damaged when the motor is running.

4. The installation of the conveyor is unstable, and severe vibration occurs during operation.

5. The rubber seal ring in the cable lead-in device of the motor junction box is aging and losing elasticity. After the wiring bucket is pressed, there is a gap between the cable and the seal ring; The fastening bolt spring washer is lost, the motor outlet box is not tightly combined with the frame joint surface, and the explosion-proof performance is lost.

6. The motor bearing is worn, the axial and radial clearance increases, and the rotating shaft moves in series during operation. At the same time, the flameproof clearance at the joint of the rotating shaft and the inner cover increases, and the minimum unilateral clearance does not meet the requirements of the explosion-proof standard.

Only by strengthening scientific management, rational use of explosion-proof motors, frequent maintenance, overhaul, and always keep the motor in good condition can we ensure the safe and reliable operation of explosion-proof motors in coal mines.