Glossary.

Back part of a shield. Within the protection of the tailskin, the segment ring is installed.

The tailskin seal is positioned at the rear edge of the tailskin and seals the annular gap between the inside of the tailskin and the outside of the segmental lining.

The electronic target is used to control the position of the tunnel boring machine. It uses sensors to measure its position relative to the laser beam and passes values to the computer in the control panel. This enables the exact position of the machine to be checked at all times.

Tunnel Boring Machine (general expression) and machine type for employment in solid rock.

Exchange  of the excavation tools requiring access to the tunnel face (sometimes via an access to the compressed air lock).

A rotating or twisting force; the product of a force and the length of a lever arm.

Trailer which can be attached to a tow vehicle and is thus mobile on the road. Serves as rig for HDD equipment.

Circular ring area at the front of the jacking pipe.

Area where the material is excavated.

General term for the construction of tunnels.