Glossary.

The cutting wheel drive; usually ring-shaped, free centre drive for the cutting wheel and/or the cutterhead of the tunnel boring machine. A large, ring-shaped bearing with internal teeth equipped with numerous pinions on the periphery, which are driven hydraulically or electrically via planetary gears. The free centre makes this drive ideal for Mixshield technology.

A jacking system, installed in the launch shaft which is often called jacking frame (pipe jacking).

Air lock to allow acces to the excavation chamber under compressed air for cutting wheel inspection, cutter change and removal of obstacles. The man lock consists of two chambers (front chamber/main chamber).

A material lock is provided on the TBM to allow tools and other materials to be passed into the pressurized chamber at the front of the TBM. In order to make the handling of heavy objects easier, the transfer lock is equipped with transport trolleys which travel on rails.

Machines with partial face excavation.

Micromachines are manned or remote-controlled TBMs for the construction of tunnels with a nominal width of up to 4.2 m.

AVND

Technology for conveying of the extracted material with the help of muck pumps (piston pumps). It is comparable to the concrete pump technology and is employed with EPB machines.

Piston pumps for viscous slurries, plastic materials such as grout, bentonite, conditioned excavated material, etc. Can also pump solid particles up to a certain size. Suitable for high slurry pressures.