Ramming

In this process, one end of the steel casing pipe is welded onto the previous pipe in the starting pit. We fasten the other end to a pneumatic ram. This draws back and then rams the pipe into the earth.

This method is suitable for horizontal tunnels and for tunnels at a gradient. Ramming can also be employed for vertical drilling. Our machines can produce tunnels up to 50 m long. They range in diameter from 114 to 2500 mm. Ramming is only possible if the ground is displaceable (soil class 1–4).

Once the front pipe has reached the target pit, we flush the pipes out with water or compressed air. In some settings, the flushing water must be pumped away and disposed of. Only then can the lines be pulled in and the tunnel filled in. Often, entire cable packages are pulled through rammed tunnels.

microtunnel_ag_schlagvortrieb.jpg

1 STARTING PIT
2 TARGET PIT
3 COMPRESSED AIR
4 PIPE RAM
5 PIPE ELEMENTS
6 PIPE FLUSHING WITH WATER OR COMPRESSED AIR
7 PULLING IN LINES
8 FILLING THE TUNNEL