Replacement of Steel Third Rail with Aluminium Third Rail in North-South Metro (Blue Line)

NEWS WAVE INDIA: Metro Railway is gearing up its assets for 150 sec headway in North-South Metro. The impact of this change will be massive on commercial Metro services. After a gap of 38 years, steel-made current conducting Third Rail is going to be replaced with Aluminium Third Rail in the North-South Metro (Blue Line). This change shall ensure 84% reduction in energy loss which is equivalent to Rs. 1 Cr / year. For laying Aluminium Third Rail, expenses will be almost half in comparison to laying per km steel Third Rail. Once completed, Kolkata Metro will belong to the league of Singapore, London, Moscow, Berlin, Munich, and Istanbul Metros where such replacement work of Third Rail has already been done and Metro services are running smoothly there.

Following their footsteps, Metro Railway has been moving towards installing highly conductive Aluminium Third Rail with stainless steel top replacing the existing steel-made third rail from Dum Dum to Mahanayak Uttam Kumar stretch of North-South Metro (Blue Line) in two phases. For this a tender has already been floated and multinational companies are showing their interests in this tender process. The replacement work will be completed in two years. Such Aluminium Third Rail with stainless steel top has already been installed in East-West Metro (Green Line), Joka-Taratala stretch of Purple Line and will be there in all upcoming corridors of Kolkata Metro.

This proposed Aluminium 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 in the running Metros. As a result, for completing one trip lesser time will be required and in turn Metro will acquire the capability to run services at lesser intervals during the peak hours. That will be an improvement in the efficiency of Metro operations. In this new system huge amount of energy will be saved which will in turn help Kolkata Metro to reduce its operational cost. As a result, the entire expenses for replacing this Third Rail could be realized within three years for 150 sec frequency by saving this operational cost.

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.