What is the function of the gearbox of the mining electric locomotive?

There is a device in the mining electric locomotive, which is a reduction box, whose function is to reduce the speed of the motor through the transmission chain, and then drive the wheelset to move. Why use a gearbox? Does it just reduce the RPM? Then why not directly control the motor speed or use a low speed motor?

Obviously, the role of the gearbox is not just to reduce the speed, and the purpose of reducing the speed is not only to reduce the speed itself. The reason why the mining electric locomotive needs to use the reduction box to reduce the motor speed, and then drive the wheelset to make the mining electric locomotive move. It is because although the motor rotates at a high speed, the torque of the motor is not large. The mining electric locomotive needs a lot of torque when driving, especially when transporting.

In addition, if the variable frequency motor is deliberately operated at a low speed, not only the torque is low, but also it is prone to heat. Therefore, a gearbox with two functions of deceleration and torque increase is very important. In addition, the gearbox also plays a role in protecting the motor. It not only provides a good airtight working environment for the rotating shaft, but also reduces the pressure on the motor after passing through the reduction box when it is overloaded.

The above is the role of the mining electric locomotive gearbox.