Zhang Jun

The first 22 city-built tunneling machines are set to help Metro workers beat a 2010 deadline.

Imported machines dug the five Metro lines now in place, but the new equipment, unveiled yesterday at a Pudong factory, will speed up work on the extra 277 kilometers of track scheduled to be opened in time for the 2010 Shanghai World Expo.

"Using our own machines we can reduce construction periods and save on costs," said Yang Guoxiang, chief engineer of the Shanghai Tunnel Engineering Company, which built the equipment.

Workers celebrate the completion of a Metro tunneling machine at Shanghai Tunnel Engineering Company factory yesterday. Photo: shanghaidaily.com

He said the machines could dig 38 meters of tunnel a day - 12 meters more than a Japanese machine.

"We have broken the monopoly on tunneling equipment in China," Yang said.

He said technical problems with imported machines could hold up construction for weeks because spare parts or technicians had to be flown in.

"We can quickly fix the problems when using our own machines," Yang said.

The machines cost about 20 million yuan (US$2.5 million), compared to a Japanese machine, which costs 30 million yuan, or a European machine, which costs 40 million yuan, company officials said. Work on the 22 machines started in February.

The company said 86 machines would be needed before 2010 to complete the Metro network.

It's not clear whether the remaining 64 shields will be city-built or imported.

By 2012, Shanghai plans to have a Metro network 500 kilometers long.