Coal mine underground operation, the working conditions are complex and difficult, the environment is harsh, the load changes with the change of geological conditions, the operation scope is more limited, there are collision, collision and falling and other dangers, there are wet, water, oil, emulsion and other effects on the motor, and there are gas, coal dust explosion risk, equipment operation vibration and other adverse conditions. How to ensure that the motor does not have accidents in operation is very important for the correct selection of the motor. Therefore, the selection of the motor must fully consider the above working environment and conditions, so that the motor itself is suitable for the requirements of the working environment and conditions in terms of structure and performance. Therefore, the following principles should be considered when choosing a motor:

1 Explosion-proof motor should be selected according to the working characteristics of the transmission machinery and environmental conditions, matching power, voltage, speed, starting torque and overload capacity. Because the coal seam cut by the shearer is sometimes filled with gangue, and the coal seam is hard and soft, the overload phenomenon often occurs when the motor is running. Roadway conveyors, especially rotary face scraper conveyors, often start with overload, and suddenly pile up coal or roll into coal during operation, so overload phenomenon also often occurs. Therefore, the explosion-proof motor with high starting torque should be selected.

2 The explosion-proof motor must be a nationally recognized inspection unit to pass the inspection, and obtain the explosion-proof certificate and production license of the product, and have the coal safety Office of the National Coal mine Administration issued a downhole certificate.

3 According to the principles of safe operation, convenient maintenance, advanced technology, economic and reasonable comprehensive analysis, scientific selection.