Meeting the high-altitude challenge
The first of 361 passenger cars Bombardier Sifang Power is building for the new line to Lhasa was dispatched to Tibet for trials in February. Designed to operate at altitudes up to 5000m, they have special equipment to cope with ultra-violet radiation, low oxygen levels and reduced atmospheric pressure
ENSURING the safety and comfort of passengers travelling on the line to Tibet was a major challenge for the supplier, Bombardier Sifang Power. The long distances, difficult terrain and high altitude of the new line meant that the cars had to be exceptionally reliable. Not only that, but they feature an array of special equipment to cope with the unusual conditions presented by the railway to Tibet.
An oxygen supply system will enable the oxygen content to be increased from 21% to around 23%. This will be distributed via the main ventilation duct as well as to individual masks for passengers. Positive air pressure inside the cars will be maintained through the use of sliding plug doors, sealed Hübner gangways and special modifications to the air-conditioning, vacuum toilets and waste water collection.
To shield passengers from ultra-violet radiation, protective film has been inserted between the panes of the double-glazed car windows. Protection from ultra-violet radiation has also been fitted to cover the rubber air bellows of the secondary suspension.
To prevent the ingress of sand and snow, most underfloor equipment is contained within a protective enclosure. The fresh air ducts of the roof-mounted air-conditioning units have been equipped with filters.
Roof-mounted GPS and broadcast antennas will be fitted with lightning protection rings no less than 8mm in diameter, manufactured from steel with a surface treatment to ensure conductivity and resistance to rust. All external and underframe wiring on the cars will be contained in a seamless metal conduit, with ends grounded or connected to an electrical device. Shielded wire is used where metal conduit is not suitable.
To protect electrical equipment from power surges, lightning protection has been built into the cable TV system and the power supply systems providing 100 and 600V DC. An earthing device has been fitted at one end of each axle.
Grey water from the toilet compartments will be collected in a non-vacuum tank inside the car bolster. The dining car is equipped with a gravity-fed tank containing up to 800litres of waste water from the kitchen, as well as rubbish compactors.
A 16-car trainset including a generator car will accommodate a total of 930 passengers. There will be four hard class coaches, each with 98 seats, and a dining car with room for 44 passengers. There will be two soft class sleepers with 32 berths each, seven hard class sleepers, each with 60 berths, and a hard class sleeper with 54 berths plus a wheelchair-accessible toilet compartment. Maximum speed will be 160 km/h.
A sub-fleet of 53 coaches is being built for 'tourist trains'. These will feature more luxurious accommodation with sleeping cars offering private showers as well as panoramic coaches.
All tests are due to be completed by the end of May, with delivery of all trains complete in June, ready for revenue service to start in July.
- CAPTION: The first set of coaches for the line to Lhasa is now undergoing type and route tests following static trials in a climate chamber and checks for noise, vibration and stability
- CAPTION: Hard class sleepers have three berths per compartment (right), while the hard class seating is arranged 3+2 in open saloons (below left). A single dining car (below right)will serve all passengers in a 16-car train