Maintenance of Permanent Way
The permanent way is the backbone of any railway system, and the safety and comfort of the travelling public primarily rests on its proper maintenance. Till a decade ago, the Indian Railways tracks were mostly manually maintained by beater packing as per a fixed timetable round the year. In recent years, however, on account of heavier and faster traffic and due to economic considerations, modern methods of track maintenance such as measured shovel packing, mechanized maintenance, and directed track maintenance have been tried and are in vogue on some sections of Indian Railways, particularly on high-speed routes.
Mechanical maintenance of the track has been introduced on about 14,500 km of high-density BG routes and the rest of the track is maintained through manual labour. The labour force directly employed for this task is about 190,000. About 3000 km of track is being maintained at present by measured shovel packing, which is an improved method of manual packing. A need-based directed track maintenance system, which initiates maintenance work only when there is actual requirement, is being increasingly introduced in order to eliminate unnecessary maintenance work. It makes the labour force more productive. About 20,000 km of track is covered by this system.
A major portion of the track, however, continues to be maintained on a predetermined cyclic programme by the manual method of maintenance, i.e., better packing. The full details of these methods of maintenance have been discussed in subsequent chapters.
With the introduction of high-capacity bogie wagons and the replacement of steam locomotives with more powerful diesel and electric locomotives, the tracks have been subjected to heavier axle loads and higher operating speeds. During the period 1950-51 to 1994-95 the average density of traffic (in terms of net million tonne kms per route km) has increased from 5.24 to 18.40 millions on BG and from 1.19 to 2.65 millions on MG. The increased track loading has necessitated improvement in the track structure and maintenance practices, specially over high-density and high-speed routes.