Multiple Machines: The Challenges and Successes of Delivering Three TBMs for Malaysia’s Longest Water Tunnel
Simultaneous delivery of TBMs, some of the most complex machines in the construction industry, is no easy task. Robbins TBM assembly is most often a local process—one that requires skilled workers with knowledge of components designed and manufactured all over the world.
Robbins use of local or nearby shops can often cut down on delivery times. A partial video of the TBM assembly process in the Robbins China-Shanghai facility is available here:
The video depicts the recent assembly of one of three 5.2 m (17.2 ft) diameter Robbins Main Beam TBMs. The machines are being built simultaneously for Malaysia’s Pahang Selangor Raw Water Tunnels, and are a good example of the assembly process.
Each machine is built at a workshop in Shanghai from components manufactured in the U.S. and China. After assembly of each machine is complete, the TBM and continuous conveyor system are shipped from Shanghai to Port Kelang in Malaysia. Once at the port, the components are trucked to the jobsite.
“One of the most difficult processes is finding a single shop that can manage the volume of fabrications and machining. The delivery times for the Malaysian TBMs are one month apart, which means that at one point you are disassembling and shipping the first machine, testing the second machine and starting assembly of the third machine,” said Kolenich. On average, each TBM requires a skilled crew of 20-30 fabricators, welders, and technicians, but shorter delivery schedules can require up to 60 people in two shifts. “We have an experienced group in China that has been building machines for many years,” he added.
Assembly of TBM #3, the first machine to be built, was completed in early July 2010. Assembly of the machine began with core components, including the main bearing and back-up structures, and finished with installation of the electrical and hydraulics systems, as well as outer components including cutterhead pieces and ground support.
“We perform all of the same quality inspections in our shops, regardless of location,” adds Kolenich. “At the end of assembly there is a two to three week no-load testing period to ensure that each machine is set up and functioning properly per the contractual and engineering requirements.”
The two other Robbins Main Beams will be completed later in 2010, with the factory acceptance for TBM #1 scheduled in August and TBM #2 in mid-September. The three machines will be launched between December of 2010 and March 2011.
For more about the Pahang Selangor Raw Water Transfer tunnels, visit the Malaysian Government’s Ministry of Energy, Green Technology, and Water.
View a short video about the project here:
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