What are the advantages and disadvantages of various railway switches?

A single turnout has a main line and a side line. The turnout is opened through the action of the point rail. The opening of the side line and the main line are controlled by the transfer machine.

A three-turn switch is equivalent to two sets of single-turn switches connected on opposite sides, but its length is much shorter than the sum of the lengths of the two sets of single-turn switches. Therefore, it is often used in railway ferry bridgehead leads, peak driving marshalling yards and areas with narrow terrain and special needs. The three-way switch consists of a set of switches and should not be used unless the operating conditions are very difficult.

The compound crossing switch is equivalent to two sets of single-opening switches laid in opposite directions, realizing the intersection of non-parallel tracks, but it has the advantages of short switch length, many openings and the two main driving directions are straight lines. It can save land, improve shunting capacity and improve train operating conditions. The intersection turnout is composed of rhombus intersections, switches and connecting curves.

Extended information

In order to increase the speed of the train when passing the switches, reduce the discomfort of passengers and prevent the displacement of goods, large-number switches can be used. For example, my country's railways generally use No. 18 for mainline turnouts, while foreign high-speed railways use No. 14, 16, 18, 20, 22, 33, and 34 switches. For safety reasons alone, the speed of trains crossing switches can also be limited.

The use of movable switches on railways has been promoted, which has completely eliminated the disadvantages of harmful spaces. The trains are much smoother and safer when passing the switches. If the turnout curve radius can be increased, the driving speed can be appropriately increased.

The characteristic of the turnout is its complex structure. The structure of the turnout is much more complicated than that of ordinary lines, because the turnout is composed of rails, sleepers, fasteners and various connecting parts. In addition, there is a conversion equipment related to electrical work in the turnout. The whole can be regarded as an electromechanical device, so the turnout is much more complex than ordinary lines.