Corrugated (roaring), Hogging, Buckling, Kinks in rails

Railway, Bridge and Tunnel Engineering

1. GOVERMENT ENGINEERING COLLEGE, BHARUCH Name : Kaptan sagar r Enrollment No. : 130140106021 Topic : Corrugated (roaring), Hogging, Buckling, Kinks in rails Sub : Railway, Bridge and Tunnel Engineering

2. Corrugated (Roaring) Rails In certain places the heads of rails are found to be corrugated rather than straight ones. Such type of rails are known as corrugated rails or roaring rails. When trains pass over such rails, a roaring noise is caused, which is unpleasant to the passengers. The corrugations consists of minute depression on the surface of rails. They are usually created at places where brakes are applied or trains start.

3. Corrugation develop in any part of the whole rail gets corrugated in a short time. Corrugation occur at any gradient and on any track, whether a straight track or a curved track. When corrugated rails are relaid in other sections, the corrugation sometimes get smoothened. When new rails are laid in places where corrugation are prevalent, the new rails get corrugated. Rails carrying empty trains are easily corrugated than rails carrying loaded trains. Some of the peculiarity of corrugated rails in nature are :

4. Causes of corrugations : Where brakes are applied to trains for stopping them. Where trains start. Where the ballast consists of broken bricks. In electrified section of a railway track. High speed of trains. Rigid railway track. Use of light wagons and coaches. Steep gradient Slipping of wheels of engine.

5. Remedial Measures The corrugations of rails can be removed by grinding a few thousands of a millimetre of the rail heads. For this purpose, rail grinding trains are used which move at 3 km.ph when the grinders are in action.

6. Hogged Rails Due to battering action of wheels over the end of the rails, the rails get bent down and are deflected at ends. These rails are called ‘hogged rails’. The hogging of the rails is mainly due to loose packing under the joints and loose fish plates. This defect causes rough riding.

7. Remedial measures : Cropping : In this measure, the hogged ends of the rails are cut off and fresh holes for fixing the fish plates are provided. The cutting of rails either is done in workshop or at the site. Welding : Hogged rails are brought to the level by welding the wornout or deflected ends. Replacing : In this method, the hogged rails are completely removed and replaced by new rails. But, this measure is very costly. Dehogging : This method involves straightening the hogged ends by means of jim crow or a dehogging machine. The dehogging machine is used with success in India.

8. Buckling of rails : Buckling of rails means the track has gone out of its original position or alignment due to prevention of expansion of rails in hot weather. Buckling, usually take place on tangent lengths or at curves.

9. Causes : When expansion gap between ends of two rails is not sufficient. The fish plates being bolted so tight that the rails are not allowed to slip or expand. Due to welded rails on weak tracks.

10. Remedial measures : Sufficient expansion gap should be provided. The fish bolts should not be tightened so much as to prevent the expansion or contraction of rails. The contact surface between the fish plates and rails should be periodically lubricated. Provision of steel sleepers or anchoring of welded rails should be done. Number of welded rails should not be large.

11. Kinks in rails : When the ends of adjoining rails move slightly out of position ‘kinks’ or ‘shoulders’ are formed. Causes : Loose packing at joints Defect in cross level at joints Defect in gauge and alignment Uneven wear of rail head

12. Effects : The kinks causes unpleasant jerks in vehicles. On curves, it causes defect in gauge alignment and camber. Remedial Measures : Providing proper packing at joints Correct alignment of joints and curves Periodical maintenance of the track in respect of gauge, welding, cross levels etc.

13. Thank you