What kind of train do you have?

Railway locomotive, also known as locomotive, is mainly used to pull railway passenger and freight trains. There are three kinds of railway locomotives, namely steam locomotives, diesel locomotives and electric locomotives.

1, steam locomotive

Steam locomotive uses steam engine to generate electricity, and drives wheels through rocker and connecting rod device.

Steam locomotive consists of boiler, turbine, frame and coal water wheel. A boiler is a component that burns fuel and produces steam. The function of steam turbine is to convert the thermal energy of steam into mechanical energy. The frame is the support for the fixed installation of boilers, turbines and other components. Deep-water truck is divided into two parts: coal tank and water tank, which are hung behind the locomotive cab. Because the steam locomotive consumes a large amount of coal per unit time, the coal pusher and coal conveyor are installed on the coal water truck, which not only improves the working conditions of the stoker, but also enables the coal to be sprayed evenly on the boiler hearth, killing two birds with one stone.

Steam locomotives have a history of 190 years. Although continuous progress has been made in traction and other aspects, the thermal efficiency is only about 8%, which is difficult to compete with diesel locomotives and electric locomotives. After 1960s, Britain, America, France and Japan stopped using it. In the late 1980s, China stopped producing new steam locomotives. However, there are still a few primitive steam locomotives that continue to play their role in some railway branches.

2. Diesel locomotive

Diesel locomotive is a locomotive powered by diesel engine, with high thermal efficiency, which can reach about 25%. Diesel locomotive consists of diesel engine and its auxiliary system, transmission device, car body and bogie. According to its transmission mode, it can be divided into electric diesel locomotive and internal combustion hydraulic pressure. Diesel hydraulic appeared in the late 1930s. It uses a diesel engine to drive a set of hydraulic transmission device, and uses liquid to transfer power to drive the walking mechanism. It developed rapidly in the 1950s. Since France took the lead in introducing AC -DC electric diesel locomotives, hydraulic transmission began to collapse. In the mid-1960s, the first AC-AC diesel locomotive was born in Britain. This kind of diesel locomotive adopts asynchronous motor, with high rated power, durability and reliability, almost maintenance-free, light weight and strong overload capacity, which is suitable for both heavy-haul freight and high-speed passenger transport. Up to now, the single locomotive with the highest power is the CP4744 locomotive modified by Canadian Pacific Railway Company and German BBC Company in 1984, with a power of 2980 kW.

3. Electric locomotive

Electric locomotive is a non-self-contained energy locomotive, which relies on catenary to provide electric energy and directly drives the traction motor on the locomotive to make the locomotive run.

The thermal efficiency of electric locomotives is better than that of diesel locomotives and steam locomotives. When power is supplied by thermal power plant, the thermal efficiency reaches about 35%; When the hydropower station supplies power, the thermal efficiency can be as high as 60% or more. In addition, electric locomotives also have the following advantages:

High power, fast start-up, fast running speed and strong overload capacity;

The locomotive maintenance cycle is long and the daily maintenance is small;

No waste gas emission, no environmental pollution.

According to the different catenary power supply systems, electric locomotives can be divided into DC electric locomotives, power frequency single-phase electric locomotives and power frequency single-phase AC electric locomotives.