Permanent Way In Railway
What is(definition of) permanent way?
The railway track of permanent nature is called permanent way or permanent track.
In other words, a permanent way is the combination of rails, fitted on sleepers and resting on ballast and subgrade.
Purpose of Permanent Way
The purpose of the permanent way is to provide a permanent facility for safe and quick movements of normal commercial traffic between the starting and destination station.
Component Parts of a Permanent Way
The following are the component parts of a permanent way: a) Formation of sub-grade. b) Ballast. c) Sleepers. d) Rail. e) Fixtures and fastenings.
Requirements of an Ideal Permanent Way
The following are the principal requirements of an ideal permanent way:
1. The gauge should be correct and uniform.
2. The rail should be at a proper level. In the straight track, two rails must be at the same level. On curves, the outer rail should have proper superelevation.
3. The alignment should be correct.
4. The gradient should be uniform. Any change of gradient should be followed by a smooth vertical curve.
5. The tractive resistance of the track should be minimum.
6. The track should possess sufficient elasticity.
7. The track should be sufficiently strong against lateral forces.
8. The radius and superelevation on curves should be properly designed and maintained.
9. The drainage system of the track should be perfect.
10. It should be free from excessive rail joints. All joints including points and crossing should be properly designed and maintained.
11. All the components of track should fully satisfy the requirements for which they have been provided.
12. There should be adequate provision for easy renewals and repairs of any portion of the track.
13. The track structure should be strong.
14. The initial cost of construction, as well as the maintenance cost of the track, should be as minimum as possible.
Functions of Curves For a Railway Track