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The Civil Engineering Department of SCR is the custodian of land and fixed assets of the railway system. Construction and maintenance of assets such as Tracks (Permanent Way), Bridges and Buildings, and the management of land are the main responsibilities of the Department. Keeping up to date with technology and modernising the maintenance organisation continuously, the Civil Engineering Department has come a long way in emerging as the backbone of South Central Railway. Assets At a Glance Track 9313 Track Kms Buildings 41,66,846 Sq.m. of plinth area Bridges 117.85 Kms. of water way Land 27,516 Hectares
Guidelines for enlistment of contractors in approved list Track Details Among the zonal railways of the Indian Railway System, South Central Railway is the fourth largest in terms of total route kms of track. SCR has 5083.38 route kms of Broad Gauge track and 650.49 route kms of Metre Gauge track. South Central Railway encompasses
nearly the whole of Andhra Pradesh and parts of Karnataka, Maharashtra, Madhya Pradesh and Tamilnadu.
According to the norms laid down for classification of routes on Indian Railways, South Central Railway System has the following configuration of route kms: Broad Gauge System
Group 'C' Classification is basically for Suburban sections of Mumbai, Delhi, Chennai and Kolkatta. As such, there is no section under Group 'C' in South Central Railway. Metre Gauge System
Group 'Q' routes are those with maximum speed of more than 75 Kmph and 'R1' routes are those with speed potential of 75 Kmph and traffic density of more than 5 GMT. There are no such routes in SCR. Group 'R2' and 'R3' routes with route of 476.90 kms are slated for conversion to Broad Gauge. In order to keep pace with the increasing traffic on various routes and also to take care of the heavier axle loads of rolling stock, Track Modernisation had been taken up as a thrust area in South Central Railway. As a part of track modernisation, heavier track structures are provided by way of provision of higher poundage and Ultimate Tensile Strength (UTS) rails on pre-stressed concrete sleepers with elastic fastening devices. Track Modernisation mainly involved the following areas:
Prior to track Modernisation, rails with weight of 90 lbs. Per metre and 75 lbs. Per metre with Ultimate Tensile Strength (UTS) of 72 Kg/mm were in use. In order to facilitate higher speeds and haulage of heavier wagons, heavier rails of 60 Kg/m and 52 Kg/m weight with UTS of 90 Kg/mm are being used while replacing existing rails. SCR has already got 5323 km of track replaced with these 52/60 kg/m rails of 90 UTS. Provision of Pre-stressed Concrete (PSC) Sleepers In SCR, as part of track Modernisation, out of a total BG running track kilometres of 6964 Kms., 645 Kms. of track has already been provided with pre-stressed concrete sleepers. Provision of Increased Clean Ballast Cushion Stone ballast provided in the track affords resilience and stability to the track, resulting in improved ride quality. As a part of modernisation, the ballast cushion below the bottom of sleepers have been increased from about 150 mm, existing earlier, to about 300 to 350 mm, after laying of PSC sleepers. Provision of PSC Sleepers in Track Junctions Track junctions (turnouts), which are provided in station yards were earlier provided with wooden sleepers and steel sleepers. In view of the higher traffic density and also to conserve precious forest resources, SCR has gone in for provision of pre-stressed concrete sleepers for turnouts in station yards as a priority area in track Modernisation. So far, 4223 points and crossings on BG running track have been renewed with pre-stressed concrete sleepers. Every year about 300 turnouts with PSC sleepers are being provided in the place of existing wooden/steel sleepers. Welding of Rail Joints Individual rails rolled in India are of 13/26 metre length. Rails, when laid in track can be joined either by provision of fish plates or by welding the rail joints. Fishplated joints in track contribute to heavy noise and bad running as wheel has to jump across the gap at the joint. Hence welding of rails is done to convert the rails panels into long or continuous welded rail panels of a few kilometres length. These panels are called Long Welded Rails (LWRs) or Continuous Welded Rails (CWRs). Welding of rails for conversion into LWRs/CWRs is another priority area in Track Modernization as this will facilitate smoother riding and also reduce the maintenance effort. Out of total BG running track kilometers of 6964 in SCR, the track in a length of 5835 Kms has so far been converted into LWR/CWR. Welding in SCR is done by two methods:
Flash butt welding technique involves pre-heating of rail ends by passing high ampere low voltage current and then the rail ends are cyclically brought closer and separated, which results in heavy sparking between the rail ends. After the rail ends are brought to a molten state, butting of rail ends is done under pressure. Flash butt joints have very high fatigue strength and are preferred to other types of welds. The rail panels of 10-rail length and 20-rail length formed by flash butt welding are transported from the Flash Butt Welding Plant to the field locations by loading into specially designed railway flat wagons. These panels are unloaded at the site through specially designed end unloading chutes fitted to the rearmost wagon. Alumino Thermic (AT) Welding AT Welding is basically a field technique, wherein the joints in the 10-rail panels are welded in the track to convert into LWR/CWR. In AT Welding, specially fabricated dry clay moulds are fitted to the rail ends to be welded, duly creating a gap of 25 mm between the rails. The gap is filled by pouring hot molten metal into the mould of the same metallurgical composition, as that of the parent rail material. Testing of Rails/Welds by USFD Monitoring and maintaining the integrity of rail/Weld sections during their service life is paramount for ensuring safety of track and increasing asset life. The rails and welds in track are periodically tested by Ultra Sonic Flaw Detection (USFD) technique to detect any incipient minor flaws caused due to the passage of traffic and prompt remedial action taken in case of detection of any flaws. Due to the passage of continuous traffic, track parameters slowly get altered and a few bad running locations get formed at isolated locations. Monitoring of the track in terms of track parametres and riding quality is done on a continuous basis by the following means:
Inspections in the locomotives of fast express/mail trains are done by maintenance Engineers periodically to identify locations of bad running which are promptly attended to. The Maintenance Engineers do physical inspection of track at periodical intervals by travelling along the track in trolleys, either motor powered or pushed manually. During these trolley inspections, the defects, if any, in the track are physically measured and prompt remedial action is taken. Measurement of Track Parametres by Track Recording Cars (TRCs) To make an objective assessment of the track parametres of the entire length of track, special Track recording cars, which carry special equipment to measure the track parameters on a continuous basis are run on various sections of the Railway at periodical intervals. Based on the assessment of the track parametres, prompt attention is given to the needy locations. Determination of Riding Quality by Oscillation Monitoring System (OMS) To judge the riding quality of the track objectively, specially designed Oscillation Monitoring System (OMS) is fitted in nominated coaches and these special coaches are attached as the last vehicle for important Mail/Express trains and oscillations are measured on a continuous basis during the run. The system generates a list of locations of the track where oscillations exceed pre-determined values, which is used by the Maintenance Organization for prompt remedial action. |
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