Kolkata Metro Railway to construct 7 more traction sub-stations in oldest corridor

Kolkata, Nov 22 (PTI) With the aim of upgrading its different systems for improvement of services, amenities and safety system, Metro Railway Kolkata will construct seven additional traction sub-stations along its Blue Line, the Dakshineswar-Sahid Khudiram (Birji) stretch.

A Metro spokesperson said Saturday that to improve train operations in Blue Line, which is a 41-year-old corridor and the country's oldest, seven additional traction substations will be constructed at Kalighat, Netaji Bhawan, Maidan, Esplanade, MG Road, Sovabazar-Sutanuti and in between Belgachia and Shyambazar stations.

With this, Blue Line shall have traction substations at each station like the Purple Line (Joka-Majerhat) and Orange Line (Kavi Subhas-Beleghata), he said.

"Apart from this, in order to meet the demand for additional traction power with fire safety, an order for two Traction SubStations (TSS) at Chandni Chowk and Geetanjali (Naktala) has already been placed. The TSS coming up at Chandni Chowk will help avoid congestion of rakes between Esplanade and Central stations," he said.

The ventilation and cooling system of stations as well as tunnels are also being upgraded.

"In the 41-year-old existing system, tunnels were also cooled as the rakes were non-air conditioned. But as Metro Railway, Kolkata is now armed with all AC rake fleet, discarding the non AC rakes, it provides the opportunity to shift to TVS (Tunnel Ventilation System) to have the state-of-the-art smoke extraction system as well," he said.

In the existing system, forced ventilation using centrifugal fans of 110 kW at fourteen midpoints are being used.

"These fans rotate 24X7 and used to consume energy incurring a cost of Rs 21 crore annually. By installing Variable Frequency Drive in midpoint in 2021-2022 this consumption was reduced by half. These fans can rotate in one direction to work as exhaust fans," the spokesperson said.

All these old fans shall now be replaced by axial fans which are suitable for two-hour operation even if the air temperature it handles reaches 250 degrees Celsius. These fans will rotate automatically when fire or smoke in tunnel occurs or ambient temperature of the tunnel crosses the set limit or concentration of CO2 or sub-soil temperature inside the tunnels crosses the set limit, he said.

"A work order has already been placed on the Indian subsidiary of a Japanese company for upgrading Blue Line's stations Environmental Control Systems (ECS) and upgrade the TVS. This holding company has already commissioned ECS and TVS systems in more than one hundred underground Metro stations in Singapore. A team of Japanese engineers has already visited Jatin Das Park station air conditioning plant and other areas," he said.

This upgrade will ensure improved fire safety, save electricity bills and reduce carbon footprint by 12,300 metric tonnes annually, he said, adding that oOnce completed, passengers will have a more comfortable riding experience. PTI SUS NN