The second Double Shield TBM for the Follo Line is completed and was recently approved. Two more high-speed tunnel borers are still in assembly at the Herrenknecht plant in Schwanau.

In total there will be four TBMs, which each will work its way through 9.5 kilometers of hard Norwegian granite. Starting from the installation site in Åsland, two will drill the tunnel northward towards Oslo, the other two will head south towards Ski.

The second TBM 981 has a white cutterhead and 71 red cutters. The colors are exactly the same as the white and red in the Norwegian flag.

"We are delighted that another TBM is ready to be transported to Norway. The first TBM arrives in Norway in May, and number two will soon follow" says Mrs. Anne Kathrine Kalager, Project Manager TBM for the Norwegian National Rail Administration (Jernbaneverket).

Fernando Vara, Project Director at Acciona Ghella Joint Venture, is also pleased with the cooperation: "We continue at full pace with the construction of TBMs, and at the site. I am glad to present the second of the four similar TBMs."

Double Shield TBMs are among the most technically sophisticated tunnel boring machines. They combine the functional principles of Gripper and Single Shield TBMs in one machine. In stable geological conditions, combining these methods permits the installation of concrete segments parallel to the drive, resulting in very high performance rates. This powerful technology is ideal for the construction of what will become the longest railway tunnel in Scandinavia.

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