RAILWAY TRANSPORTATION ENGINEERING
5. Rail Fastenings
Fittings and fastenings are used for joining rails together as well as fixing them to the sleepers, and
they serve their purpose so well that the level, alignment, and gauge of the railway track are
maintained within permissible limits even during the passage of trains.
5.1. Rail Joints
Rail joints are necessary to hold together the adjoining ends of the rails in the correct position,
both in the horizontal & vertical planes. It is the weakest part of the track.
5.2. Avoidance of Rail Joints
Problems created due to Rails –joints
a. Weakest link in track
b. Break of continuity (horizontal & vertical)
c. Blow of wheels–loosening of fish plate, ballast, fastenings etc.
d. Wear & tear of track components
e. Impact at rail joints – reduce life span of rails, sleepers & fastenings
f. Noise is created
g. Increases fuel consumption
Requirements of an Ideal Rails joints
a) Holding rail ends for continuity.
b) Sufficient strength & stiffness.
c) Adequate expansion gap.
d) Easy removal or replacement, flexibility.
e) Provision for wear at rail ends. It should not allow the rail ends to get battered in any case.
f) Adequate elasticity.
g) The joint should fulfill the above requirements with the minimum of initial & maintenance cost.
(i.e. it should be economical)
Possibility of Avoidance
a. Manufacture of longer rail as possible.
b. Use of CWR
c. …….
Er. Parivesh Parajuli | PURWANCHAL UNIVERSITY [EASTERN COLLAGE OF ENGINEERING]
RAILWAY TRANSPORTATION ENGINEERING
5.3. Types of Rail joints
a. Supported rail joint
b. Suspended rail joint
c. Bridge joint
Er. Parivesh Parajuli | PURWANCHAL UNIVERSITY [EASTERN COLLAGE OF ENGINEERING]
RAILWAY TRANSPORTATION ENGINEERING
d. Base joint
This is similar to bridge joint, with the difference that the inner fish plates are of bar type and outer
fish plates are of the special angle type, in which the horizontal leg is further extended over the
sleepers to be bolted to both bridge plate and sleeper. • Due to complicated design, this is not
generally used.
e. Welded rail joint
f. Staggered / broken joint
The joints on railway track are not directly opposite to the joints of the rail track.
These joints are generally provided on curves, where the length of outer curved track is greater
than the length of inner curved track.
Er. Parivesh Parajuli | PURWANCHAL UNIVERSITY [EASTERN COLLAGE OF ENGINEERING]
RAILWAY TRANSPORTATION ENGINEERING
g. Square joint/Even joint
The joint of the one railway track are directly opposite to the joints of other rail track.
This type is generally used on straight track.
h. Compromise joint
Where two different rail sections are required to be jointed together, it is done by means of fish
plates which fit both the rails and this is joint termed as compromise joint
i. Insulated joint
When insulating medium is inserted in a rail joint to stop the flow of current beyond the track-
circuited part, it is called insulated joint.
Er. Parivesh Parajuli | PURWANCHAL UNIVERSITY [EASTERN COLLAGE OF ENGINEERING]
RAILWAY TRANSPORTATION ENGINEERING
j. Expansion joint
In bridges, provision for expansion and contraction is kept for girders and rails both.
5.5 Fish Plates
The name ‘fish plate’ derives from the fish-shaped section of this fitting. The function of a fish
plate is to hold two rails together in both the horizontal and vertical planes. Fish plates are
manufactured using a special type of steel (Indian Railways specification T-1/57) with
composition given below:
Carbon: 0.30–0.42%
Manganese: not more than 0.6%
Silicon: not more than 0.15%
Sulphur and phosphorous: not more than 0.06%
Er. Parivesh Parajuli | PURWANCHAL UNIVERSITY [EASTERN COLLAGE OF ENGINEERING]
RAILWAY TRANSPORTATION ENGINEERING
Er. Parivesh Parajuli | PURWANCHAL UNIVERSITY [EASTERN COLLAGE OF ENGINEERING]
