The CCL will be 33.3 km long with 29 stations. Starting from the Dhoby Ghaut station, it will run through some of the busiest corridors in the city and end at Harbour Front station on the North East Line. The project will be implemented in five stages and is expected to be ready by 2010.
CNA is involved in the implementation of the Tunnel Ventilation System and Environmental Control System for CCL Stage 2, 4 and 5. Our total contract value is S$4.16 million. Stage 2, 4 & 5 will complete in Feb 2009. CNA was also involved in the previous MRT lines – North East Line, Changi Line, East-West Line, Woodlands Line and upgrading of the East-West Line.
CCL Stage 2 comprises five stations, connecting tunnels and a depot and joins the Stage 1 Circle Line at the end of the Boulevard Sidings. The five stations, located over a route of approximately 5 Km, are Old Airport Road, Tanjong Katong, Paya Lebar Interchange, MacPherson and Upper Paya Lebar. Old Airport Road, Tanjong Katong and MacPherson stations are to be constructed as Civil Defense shelters.
CCL Stage 4 and 5 comprise twelve stations, one RTS facility building, connecting tunnels, siding and crossover tracks. The stations and facility building, located over a route length of approximately 17 Km, are Thomson Station, Bukit Brown RTS Facility Building, Botanical Gardens Station, Farrer Station, Holland Village Station, Buona Vista Station, One-North Station, Kent Ridge Station, West Coast Station, Pasir Panjang Station, Labrador Park Station, Telok Blangah Station and Harbour Front Station. Thomson station, Botanical Gardens station, Buona Vista station, West Coast station and Labrador Park stations are to be constructed as Civil Defense shelters. Buona Vista and Harbour Front Stations are interchange stations with the existing East West Line and North East Line respectively.
CNA provides a Local Sequential Control System (LSC) for the Environmental Control System and Tunnel Ventilation System. The LSC system design is based on a fail-safe, dual-redundant Programmable Logic Controller (PLC) System to enhance the robustness of the Tunnel Ventilation System and Environmental Control System for maximum commuter safety. The contract requires the PLC system to be developed in accordance with the standard EN 50128, to a Safety Integrity Level of 2.
The role of the Tunnel Ventilation System is to provide an acceptable environment condition within the tunnel for the operation of trains during normal and congested operating conditions and an effective means of controlling smoke flow during emergency condition. Tunnel ventilation shafts and fan system are located at both ends of the tunnel for each of the stations to ensure acceptable operational conditions for the equipment and comfort to the operators.
The Environmental Control System ensures a comfortable and safe environment for commuters, station personnel and equipment in the station. It provides smoke control during fire emergency and interfaces with the Fire Protection System to shutdown appropriate equipment and operates the Smoke Purge System during an emergency.
The Smoke Purge System is part of Environmental Control System. It consists of a smoke control panel, smoke purging fans and supply air fans. The smoke purging fans are provided for the station public areas and service corridors at ancillary area. Supply air fans are provided for the smoke stop lobbies and emergency / firemen staircases.
CNA has a proven track record in delivering robust and reliable environmental control systems and tunnel ventilation systems in Singapore. Our ability to understand and meet LTA's stringent safety and reliability requirements has resulted in our winning of almost all the MRT contracts in Singapore. |
