Ordinary Simple Railway Turnouts

Railway Turnous can be divided into different classifications, such as ordinary simple railway turnouts, symmetric railway switch and line crossing railway switch. Today, we will have a discussion on the ordinary simple railway turnouts and the components.

This type of rail switch is the equipment that divides one rail into two rails. There are straight stock rail and curved stock rail, which are divided into left hand and right hand. As the curved stock rail turns left, it is called left hand turnout; conversely, it is called right hand turnout.
 

Rail Switch

Rail switch is a guiding device that guides the locomotive or vehicle into different directions of the turnout. It is operated by pulling switch rail to different positions to guide a train to run along the straight stock rail and curved stock rail of the turnout. Switch is composed of two stock rails, two switch rails, various connecting parts and turning machinery.
 

A. Stock rail and switch rail

Stock rail is made of ordinary steel rails, which are divided into straight stock rail and curved stock rail. In order to maintain certain rules, the curved stock rail should be bent into an appropriate folding line. Stock rail has the same function as a normal rail and also withstands horizontal force from trains together with switch rail. In order to prevent lateral movement, the stock rail is not provided with rail braces in the range of outside switch rail.
 
Switch rail is one of the important components in the switch system. It is made of the same type of stock rail by the cutting. It can be divided into two types: straight type and curved type.
 

B. Heel structure of switch rail

Heel structure of switch rail is the connection point of the switch system. It enables the rail to swing left and right on the plane according to different switch requirements and makes a train remain stable when passing. The heel structure is composed of filler, rail fish plate, sleeve, bolts and so on.
 

C. Other components

In order to ensure that switch rail is flexible and stable, the necessary components are provided in the joint of the heel structure of switch rail and the connection of switch rail and stock rail.
 

a. Connecting rod

The function of connecting rod is to connect two switch rails into one unit, which can fix the distance between two rails and prevent them from striking when a train passes.

b. Rail brace and slide plate

In order to enhance the lateral stability of the contact surface between switch rail and stock rail, rail brace is installed at the outer side of stock rail, and there are shoulders at the outer side of slide plate for supporting rail brace. The role of rail brace is to prevent lateral movement of stock rail.

Slide plate is used to support the pressure transmitted from switch rail and stock rail and transfer it to rail sleeper. Each plate has a convex platform that ensures that the switch rail can smoothly swing to left and right, and the platform also has the function of preventing stock rail from moving inwards.
 

Frog and guard rail

Here includes frog, guard rail, stock rail for mounting guard rail and other connecting components.
Frog consists of point rail and wing rail. There are two types of frogs for simple turnout: bolted rigid frog and integral casting frog.
The frog throat is the starting bend of the working edge of wing rail and the narrowest distance between the working edges of two rails.

2. Bilateral turnout

Bilateral turnout is the equipment that separates the railway track from the left and the right. Both sides are curved rails and symmetrical to the center line of the straight track.

3. Crossover turnout

Crossover turnout is the equipment that connects two adjacent railway tracks. Single crossover turnout consists of two sets of simple turnouts with same turnout number and a section of connecting rail. It is always used when a train travels from one rail to another.