Types of Rail Joint ?
A Joint made between two rails and this incidentally forms the weakest part of the track is known as Rail Joint. Many fastening are found out to move this joint as much as efficient as possible.
Depending upon the position of joint or sleeper, the types of rail joint are classified as follows :
Types of Rail Joint According to Position of Joint :
1. Square Joint :
When a joint in one rail is exactly opposite to the joint in other parallel rail is called as square joint. This types of rail joint is very common in straight tracks but at present the staggered joint are more favoured.
2. Staggered Joint :
When a joint in one rail is exactly opposite to the center of parallel rail length it is known as staggered joint.
Advantages of Staggered Joint :
- The centrifugal force on a curved track will have a tending to push the track out of line and as the weakest part of the track is the joint, this effect would be joint previously.
- It is found that the staggered joint reduce the tending of centrifugal force.
- It is observed that staggered joint produces smooth running than square joint.
Also Read : Coning of Wheels
Types of Rail Joint According to Position of Sleepers
1. Suspended Joint :
The rail joint when placed at the center of the two consecutive sleeper is known as suspended joint.
It is claimed that load is equally distributed on 2 sleepers and also when joint is depressed both rail ends are pressed down. They however require more maintenance.
2. Supported Joint :
When the sleeper is placed exactly below the rail joint it is known as supported joint. This type of joint is not used at present. It is found from experience that the supported joint give sufficient support with heavy axle load.
3. Bridge joint :
This joint is just similar to the suspended joint. But in this case a length of metal serving as bridge is used to connect the end of two rail so that there is no bending stresses in rail. To rest the bridge on two sleepers they are not head out. But a experiment have shown that this type of joint is not possible in a actual practice so presently it is not favoured.
Requirements of Good Rail Joint
- It should be strong, stiff and give some strength as that of the original rail section.
- It should be cheap and durable.
- The rails provide continuous and level surface for movement of train.
- It should maintain the gauge distance of the track.
- It should not allow the rail end to be battered in any case.
- It should be capable of maintaining the two rails at the same level.
- It should provide free expansion and contraction due to temperature.
- There should be easy removal and replacement of rail without disturbing the whole track.
- It should be elastic both laterally and vertically.
Also Read : Ballast in Railway : Types and Functions