New trains for the Downtown Line are put through a stringent testing process to ensure they are safe and reliable for service, said the Land Transport Authority (LTA).
The first two trains built for the line went through an 18-month testing phase at a 3km track in Changchun, China. This is three months longer than earlier testing for the North East and Circle Lines, and allows for more comprehensive trials.
Contractors are brought in for tests to integrate the trains with other key components such as the signalling system, communications system and platform screen doors.
The LTA awarded a $571 million contract to Canadian manufacturer Bombardier Transportation in Nov 2008 after a "stringent tender process" to design, manufacture, test and supply 73 three-car trains for the Downtown Line.
Speaking to reporters during a visit last week to the Changchun Bombardier Railway Vehicles Company (CBRC) facility where the trains are built, LTA senior group director for rail Sim Wee Meng said: "When deciding on the award, LTA also considered CBRC's track record, safety record and technical expertise."
Train assembly began at the CBRC facility in Changchun, China in June 2010. There are Bombardier staff from its head office in Hennigsdorf on site to supervise the works, while the LTA also has staff in Changchun to keep an eye on various processes.
Formed in 1997, the CBRC has supplied hundreds of train cars for cities like Shenzhen and Shanghai. CBRC general manager Stephen Barry told The Straits Times the China facility has the latest equipment, and meets all of Bombardier's standards for manufacturing and quality control.
"We are a very mature, experienced manufacturer," he said.
The DTL trains are made of welded aluminium panels and are 90 per cent recyclable.
Bombardier is the world's largest supplier of metro trains. The trains on the other MRT lines are either from Japan's Kawasaki, France's Alstom or Japan's Kawasaki.
The DTL contract is one of several the LTA has awarded to consortiums that manufacture the rolling stock in China. For instance, the Shanghai Alstom Transport Co is supplying 18 six-car trains worth $234.9 million for the North East Line, and 24 three-car trains for the Circle Line for $184.2 million.