Microtunneling

The most demanding, yet most refined drilling technique is microtunnelling. This method is a combination of thrust boring and HDD. This drilling method can be used either in soft soils or in rocky ground (up to soil class 8). The drive is inside the pipe at the tip of the borehole. The cutter head turns, crushing the material in front of it, thus advancing slowly through the earth. At the same time, the presses in the starting pit exert a constant pressure. In this method again, the steel casing pipes, concrete pipes or Hobas jacking pipes (500–1500 mm diameter) are built together in the starting pit.
The cutter head can be steered to all sides. Like with HDD, the system is lubricated with a bentonite/water mixture.
A feed pipe pumps the cleared earth to the surface and into a separation system.
Microtunnelling is a self-contained and tight system. Thus it is even possible to bore through ground water and beneath rivers. Using our equipment, we can drill up to 150 m in length.

1 STARTING PIT
2 TARGET PIT
3 WATER
4 HYDRAULICS
5 POWER
6 PRESS STATION AND LASER
7 INTERMEDIATE PRESS STATION
8 CUTTER HEAD