Ramming with displacement (Displacement mole)

When tunnelling at relatively small diameters (45–190 mm with expansions up to 300 mm) and short distances (up to 20 m), we employ the displacement mole. This soil displacement hammer is pneumatically driven. The leveller is sighted in the target pit through a telescopic sight. The displacement mole pulls the product pipe – typically polyethylene (PE) – behind it. It can be used for both horizontal and vertical boring, although only when the ground is displaceable (soil class 1–4). We use the displacement mole mainly for building connections (gas, water, telecommunications etc.).

1 STARTING PIT
2 TARGET PIT
3 COMPRESSED AIR
4 PRODUCT PIPE
5 DISPLACEMENT MOLE