TERRA-JET DJ 10 drills gas line

Spülbohranlage TERRA-JET Gasleitung, HDD machine directly on the road, © TERRA AG, Reiden, Switzerland
The contractor Salzmann Erd- und Betonbohrungen from Oberstetten, Canton St. Gallen, Switzerland has used its directional HDD drilling machine TERRA-JET DJ 10 to lay a gas line in the city Sirnach. Therefore the HDD machine was installed directly on the road, which was blocked due to the open trench for the main gas pipeline. The directional pilot bore was 49 m (160 ft) long. After 20 m (66 ft) an existing telecom cable had to be undercrossed. During backreaming a HDPE pipe OD 125 mm (5”) was pulled in. The HDD machine TERRA-JET DJ 10 is equipped with 2 m (6.6 ft) long drill rods, which allow a minimum bending radius of 25 m (82 ft). The torque of 1’800 Nm (1‘350 ft.lbs) and the thrust and backream force of 40 kN (4 tonnes, 8’800 lbs) allow bore channels up to ø 200 mm (8 ft). It was not possible to position the HDD machine at the higher end of the bore. Therefore the bore started at the lowest point. The drill rods had to be bent upwards by 9 % per drill rod. The drill head reaches the arrival pit right on target. The backreamer ø 160 mm ( 6.3“) and the HDPE pipe ø 125 mm (5“) are assembled and pulled in. The mixing and pumping station, the drilling fluid tank and the tools are installed on the trailer. This allows easy mixing of the Bentonite into the drilling fluid. The complete 49 m (160 ft) long bore including pipe pulling took half a day.
Spülbohranlage, drill rods had to be bent up © TERRA AG, Reiden, Switzerland
Bohrarbeit, pilot bore © TERRA AG, Reiden, Switzerland
zielgenaue Ankunft, reaches the arrival pit right on target © TERRA AG, Reiden, Switzerland

Tank und Werkzeug, drilling fluid tank and the tools© TERRA AG, Reiden, Switzerland
Schutzmantelrohr, HDPE pipe has been butt welded © TERRA AG, Reiden, Switzerland
Aufweitkopf mit Rohr, backreamer arrives with a pipe in the starting pit © TERRA AG, Reiden, Switzerland


TERRA AG für Tiefbautechnik - Hauptstrasse 92 - 6260 Reiden - Schweiz - Tel. +41 62 749 10 10 - office@terra-eu.eu