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NFM Technologies Pockets Major Contract for Six TBMs in China

NFM Technologies Pockets Major Contract for Six TBMs in ChinaNFM Technologies, affiliated to Wirth, has won an order for the supply of six slurry Benton'air® type TBMs to China. The contract is worth more than EUR70 million and entails the design, assembly and commissioning of six machines, with diameters of 11.93 m and 11.12 m. The TBMs will be used on two different railway projects. Visit www.nfm-technologies.com and www.wirth-europe.comThe first project is a 9.4 km new rail line to link the central and west main stations in Beijing, whereof 7.2 km to be built underground by two 11.93 m-diameter TBMs. The new line must be operational for the 2008 Olympic Games. The second project is the Shiziyang tunnel on the Guangzhou-Shenzhen express line. The tunnel consists of two tubes, with lengths of 4,540 and 4,500 m. Four 11.12 m-diameter machines will be employed, one starting from each end of the two bores. Click cn/75.Delivery of the TBMs is scheduled for the summer of 2007. To take up the challenge in terms of industrial production time, NFM Technologies will act as chief architect while its partner Shenyang Heavy Machinery Group in China will produce certain components and will assemble the machines. This new major contract gives the Wirth Group a leading position in China for large diameter TBMs, with more than 30 references to date.The TBMs will use a slurry mucking-out system named Benton'Air®. The mud, produced in a mud plant by mixing water and bentonite, is injected to the tunnel face. The slurry is regulated thanks to the presence of a big air bubble in the upper part of the excavation chamber. The soil that is excavated is mixed with the mud and mucked away by an extracting pump and conveyed through a mucking pipe. Once the materials (mud and spoil) have reached the surface, they are separated in a slurry plant to recycle the mud and thereby reduce the volume of the spoil. 35/06.