The TBM beneath the Himalayas bores with a cover between 750 – 1000m at an altitude of 2430m. Seli stated that another factor in the efficiency of the TBM has to do with machine specifications, which were developed to handle variable and exceptional working conditions.
The features include a 19in (483mm) cutterhead design, 350mm of maximum total overcutting that is adjustable depending on geology, and the ability to rotate the cutterhead even in the presence of collapsing faces.
The project is expected to be completed in June 2014.
