A Machine To Saw Through The Mountain

Lane enlargements are a common annoyance for drivers - traffic jams, closures and disabilities often disturb for weeks. In Italy, the Montedomini tunnel has now been impressively expanded from two to three lanes on the Autostrada Adriatica - without any interruptions. The road connects the north of the country with the boot heel and is therefore heavily used.

At the port city of Ancona, a further tunnel was built into the existing tunnel through which traffic could flow during the construction work. Meanwhile, people and machines worked between the two tunnel ceilings.

The mountain saw saws the new tunnel floor

From the 3rd minute you can see the mountain saw in action

Impressive machines such as the mountain saw that the Italian Palmieri Group designed for the project were used. The eight and a half meter long saw sawed the new tunnel floor into the mountain. The conditions for the technology were extreme: the machine had to withstand dust, heat and moisture.

Palmieri chose a Hägglunds hydraulic motor and a closed hydraulic system from Rexroth for driving the saw, through which two axial piston variable pumps pumped the fluid. (kj)