Turnout is a kind of railway track connecting equipment that enables locomotives to move from one track to another track. It is usually laid in a large quantity at a station or marshalling stations. The turnout can give full play to the passing capacity of the line. Even for single track railway, laying turnouts and building a longer branch line than the length of train can make the train run in opposite directions. Turnouts are very important for railway lines operation.
Composition of single turnout:
Switch part: stock rail, switch rail and switch machinery.
Frog and guard rail: frog core, wing rail and guard rail.
Connecting part: straight rail and curved rail.
High manganese steel integral casting Frog: the main material of the frog is high manganese alloy steel, which is used to cast the wing rail and the center rail into one body. It has the advantages of long service life, few parts, solid structure, and can always keep the correct flange groove and control size, so as to improve the stability and safety of the driving.
Movable core rail frog: use the core rail to swing and close to the wing rail to eliminate harmful space.
The straight rail of the frog is not equipped with guard rail, and the core rail is close to the wing rail, so that the track line is continuous, avoiding the impact of the wheel on the wing rail and the core rail, and greatly improving the speed of the train passing through the turnout.
As the usage, turnout has the kinds of Single (simple) turnout, Equilateral turnout, Compound turnout, Crossover turnout and Combined turnout.
As the different sleeper, has the kind of Wooden sleeper turnout and Concrete sleeper turnout.
Regulations for selection of turnout number:
1. The direct passing speed of the train at the main line turnout shall not be less than the design running speed of railroad.
2. In the section where the direct passing speed of the train is 100-160km/m, the turnout of the main line shall not be less than No.12. Under difficult conditions, No. 9 can be adopted for stations in reconstructed sections and above.
3. In the section where the direct passing speed of the train is less than 100km/h, the main line turnout of the passing station, overtaking station and intermediate station receiving and departing the train laterally shall not be less than No.12, and No. 9 can be used for other stations and rail lines.
4. No. 18 single turnout shall be adopted for the train with lateral passing speed greater than 50km/h but not greater than 80km/h.
5. The lateral passing speed of the train shall not be greater than 50km/m for single turnout, and shall not be less than No.12.
6. The turnout for receiving and departing passenger trains on the side shall not be less than No.12. Under difficult conditions, the turnout for receiving and departing passenger trains on the non main line can be No. 9 symmetrical turnout.
7. Movable center rail single turnout shall be adopted for the line with the train passing speed of 160km/h and above.
8. The turnout with the direct passing speed of the train greater than 120km/h shall adopt the transfer external locking device.
9. The turnout with concrete sleepers shall be adopted for the main line with design running speed of more than 120km/h; For the main line and station track with the design running speed of 120km/h and below, the turnout with concrete sleepers should be preferred.
Note: AT track switch is a switch made of low profile special section rail, and the movable joint is eliminated.