Mechanized Methods of Railway Track Maintenance

Mechanized Methods of Track Maintenance

The need to switch over from manual to mechanized methods of track maintenance is progressively being felt due to the following reasons.

(a)  Beater packing is a very hard and strenuous job and thus the labourers have a tendency to shirk from doing this type of work.

(b) It is difficult to ensure the uniform quality of the compaction under the sleepers carried out by manual means due to the uncertainties associated with the varying physical strength of the labourers, commitment of the workers, varying weather conditions, and other allied factors.

(c)  The intensity of the pressure and shock that the ballast is subjected to when the beater is being used is very high and in many cases exceeds the crushing strength of the stone. This results in the progressive clogging of the ballast section.

(d) Traffic densities, axle loads, and speeds have increased considerably on Indian Railways considerably in the recent past. Beater packing does not enable track geometry to be maintained within the tolerances prescribed for a satisfactory length of time.

(e)  The retention of the packing done via manual maintenance is not very good and the track geometry gets distorted in a short time due to high-speed traffic.

(f)  Manual maintenance is not much suited to the modern track, which consists of long welded rails and heavy concrete sleepers.

(g)  With the increase in traffic density, the time available between trains is becoming progressively short. It is, therefore, becoming increasingly difficult to maintain tracks by manual methods, which take a considerably long time.

(h) When a track is maintained manually, it takes considerable time for it to get fully consolidated and, therefore, speed restrictions exist for a long period after track renewal work has been completed.

(i)  Manual methods do not emphasize on the identification of defects and monitoring of the work being done. These are, however, done in the case of modern methods of track maintenance, thereby giving move effective results.

Some of the important heavy track machines being used on Indian Railways (IR) are listed in Table 20.1.

Table 20.1   Track machines in use on IR

On railways, the mechanized maintenance of tracks normally involves the use of mechanical tampers, which are used to tamp or pack the ballast. Mechanical tampers are generally of two types, namely, off-track tamper and on-track tampers.