Mechanical moles

A tunnel boring machine (TBM) is a mechanised tunnelling machine, a huge steel can or shield with a rotating cutter head at its front end which holds special tools for biting into the ground. Earth is transported from the cutter head, through the machine and the tunnel and out to the surface.

Often the TBM, and the miners who operate it, will place precast concrete tunnel lining segments as the machine moves forward. All TBMs pull behind them a series of decks which carry the machine’s ‘back-up’ such as electrical and mechanical systems, ventilation and grouting equipment. It’s a bit like a mobile, underground production line.
Herrenknecht has been making tunnelling equipment for over 40 years. With 4,100 mechanised tunnelling projects under its belt, nearly 5,000 employees around the world and a revenue of €1.2 billion in 2017, it can rightfully claim to be the world’s leading TBM manufacturer.