SOLUTION

DC Motor with Ward Leonard Speed control, Double Squirrel cage Induction Motor, Slip Ring Induction Motor with rotor resistance starter drive can be used for Mining Process.

Coal and Mining Industry:-

The motors used in coal and mining are classified into two groups. The first group drive is for mine accessories such as compressors, pumps, etc. While the second motors are used for the actual mining process i.e. to drive the cutters, drillers, etc.

It is necessary that the motors used for coal and mining must be flameproof. The atmosphere is generally hot with high ambient temperature and also humid. The motors should have humid-proof insulation. 

The coal cutting or drilling does not require any speed control as the processes are constant speed processes. High starting torque is necessary. The high starting torque squirrel cage motors with a double cage are preferred for these applications.

For haulage purposes, the motors are able to start large drums. So they must have high starting torque. The speeds required are different at different haulage stages. Frequent starts and stops are required. To meet these requirements the slip ring induction motor with rotor resistance starter is preferred.

The mine winder motor may be a D.C motor win Ward Leonard speed control or slip ring motor with rotor resistance starter is preferred.

The centrifugal pumps are used in mining for various jobs like pumping water. The high torque squirrel cage motors which do not have any maintenance problems are selected.