Traction locomotives on China's railways can be divided into passenger locomotives, freight locomotives, dual purpose locomotives, transfer locomotives, industrial and mining locomotives, emu locomotives, high-speed railway locomotives and so on.

Passenger locomotive: it is specially used for traction locomotive of passenger train, for the characteristics of the traction is not big, but requires speed, as long as can achieve traction train speed, don't need to care about is too big traction, locomotive on the brakes and the car speed is fast, and have maneuverability, at the time of traction train, the train itself does not consume traction, only play the role of guiding direction, can be fast trains running. Freight locomotive: it is used to pull freight train locomotive, its own traction power, and in some places for the speed of the locomotive also has certain requirements. But generally speaking, the speed of the locomotive is not too high requirements. Freight locomotives have great traction power. Therefore, when a freight locomotive drives a vehicle, it consumes a large amount of power. The train runs with the maximum power, and the speed is uniform. The brake is fast and the lift is slow. For traction power and other indicators are very high requirements. High-speed railway locomotive: it belongs to the scope of passenger locomotive, and there are a few freight locomotives. There are fixed modes for traction power, model and speed, etc. However, the general high-speed railway locomotive requires speed rather than traction.

In a word, passenger locomotives, emus locomotives and high-speed railway locomotives belong to the scope of passenger locomotives, which require high speed. They do not have too high requirements for traction power and pull a small number of long vehicles for fast running. Freight locomotive traction power requirements, for a number of cars jogging; Each index of small locomotive is different from that of passenger locomotive and freight locomotive. The shunting locomotive requires high traction power, but the speed is not necessarily too fast, which can facilitate the reciprocating operation; Mining locomotive speed and traction are not too high requirements.

Dual purpose traction locomotive: usually also known as a small locomotive. In the railway is a general locomotive, speed and traction power and the difference between the two types of passenger and freight locomotives. In terms of traction of passenger cars, the speed and power are relatively balanced. In terms of freight, it is mostly used for small running fast freight trains on the railway, and the number of train sections is relatively small, so as to realize less pulling and fast running. Therefore, the traction power consumed by this locomotive in the traction of the train is not very large. Shunting locomotive: it is a locomotive specially used for lifting and assembling trains. It is generally designed as an outer corridor. Not used as a trunk locomotive. The requirement of the locomotive is to have too much traction power, but not too high speed requirements. Because the locomotive in the railway reciprocation is more frequent, therefore, the requirement is in the locomotive in the process of traction train, the speed should be fast. And the brake and lift are fast, and smooth operation, traction power to have good and smooth characteristics, can have the convenience of the train. Industrial and mining locomotive: it is a locomotive engaged in transportation in factories or mines and factory areas.

There is no high demand for traction power and speed. Industrial and mining locomotives are generally freight locomotives. Therefore, traction power does not belong to the scope of general locomotives. Emu locomotive: a special type of locomotive, whose rear end is connected to the carriage. It is single-sided traction locomotive, whose traction force on the railway is pulling and propulsion. Belonging to the scope of passenger locomotives, brake and lift speed is fast, and smooth operation, speed. Little traction is expended.