In the little Village Wimmis in the beginning of the Swiss Alps (Berner Oberland) two steel pipes with Ø 600 mm (24“) had to be laid underneath the railway in a length of 17 m (56 ft). Both parallel steel pipes were laid as casings for product pipes for a district heating network. The contractor Burn & Künzi from Adelboden and Oey decided to ram these steel pipes trenchless with his TERRA-HAMMER TR 360.
The ground consisted of gravel, stones and boulders. Therefore the foreman decided to stabilise the front of the steel pipe by an outer and an inner cutting ring.
The steel pipe ram TR 360 is connected to the first steel pipe
The ramming speed was at 4 m/h (13 ft/h). It slowed down under 1 m/h (3 ft/h), when the steel pipe hit rock or bolders. Both steel pipes were cleaned with a sewer cleaning truck. Its high pressure pump produced over 150 ltr/min (40 gpm) at 150 bar (2’200 psi).
One of the steel pipes reached the arrival pit. The cutting rings were cut off. Then the product pipe was pushed in.