AMAR METRO
KOLKATA
PRESS RELEASE
METRO RAILWAY CONNECTS CENTRAL AND SHYAMBAZAR RECEIVING SUBSTATIONS THROUGH ENERGY EFFICIENT HIGHLY CONDUCTIVE ALUMINUM THIRD RAIL
Kolkata, 05.01.2025
Metro Railway, Kolkata has achieved the first milestone for replacement of Steel third rail by highly conductive Aluminum third rail. Installation of the highly conductive Aluminum third rail between Shyambazar and Central station of the DN line has been completed. The length of this section is approximately 4 kms. This Aluminum third rail may be seen at Shyambazar, Shovabazar-Sutanuti, Girish Park and Mahatma Gandhi Road stations in the DN Line (towards Kavi Subhash).
Earlier Metro Railway, Kolkata had made trials in the month of September to November 2024 in different sections like Girish Park, Maidan sidings and Central Main line. The work has started in full steam in the month of December 2024. Around 3500 mtr rail has been replaced in the month of December 2024. Now, approximately 4000 mtr will be replaced every month.The work of replacement in the underground section has been targeted for completion within August, 2025. Earlier, the rail was being replaced after taking power blocks on Saturday nights. Now, the replacement is being done on weekdays also.
The replacement work is extremely challenging as delay in completion of day’s work may lead to traffic disruption in the morning. So, all steps are monitored critically and after detailed minute to minute planning, back up planning and fall back strategy in place the work is executed. First new pedestals are made of appropriate height with best material available in the market (M65 pre mix concrete to avoid any adulteration and quality compromise). Then all materials like third rail components and shroud boards are brought to the site and kept in safe location. one day before the scheduled work, the shroud boards of existing rails are removed. on the execution day, existing steel rails are cut at marked locations and dismantled. New GRP (Glass Reinforced Plastic) insulators are placed on the pedestals. Then the new highly conductive Aluminium third rail is placed on the insulators after adjusting height and distance. Interconnection with the existing power supply system is done with cables. After all adjustment of mid-point anchor, expansion joints and cable connectors, one final checking of tightness of all fasteners are done. Finally, the shroud boards are placed on the rail.
This highly conductive Aluminum third rail has the capacity to reduce the system voltage drops and subsequent energy losses, thanks to its superior electrical conductivity. This less voltage drop in the third rail will help to achieve faster acceleration of the running Metros. That will be an improvement in the efficiency of Metro operations. In this new system a huge amount of energy will be saved which will in turn help the Metro Railway to reduce its operational cost. As a result, the entire expenses for replacing this third rail could be realized within three years by saving this operational cost. Additionally Aluminium third rail shall reduce carbon emission by 50000 ton in its lifetime.
Apart from this, Aluminium third rail will require less maintenance and will be highly reliable and stable. In a hot and humid city like Kolkata, this replacement will be very much beneficial and inside the tunnel lesser heat will be generated during the time of contact of Third Rail Current Collector (TRCC) with this third rail. For maintenance work the new third rail will not require any welding as two such rails can be joined with the help of splice joint. It will help to maintain the air quality inside the tunnels.
.jpg)
.jpg)
.jpg)
.jpg)
