The French contractor Gauthey TP of La Ravoire had to renew around 250 m (825 ft) of a sewer and de-watering system for the factory of Placoplatre in Chambéry. The old pipes had an inner diameter of Ø 300 mm (11.8”) and Ø 400 mm (15.75”). They decided to use the Cable Burster TERRA-EXTRACTOR X 400 and the PIPe method (PIPe = Pipe In Pipe). They operated from manhole to manhole without digging any pit. For this relining job they pulled in short pipes with OD 280 mm (11”) and 375 mm (14.75”).
Gauthey TP is a specialist in pipe and cable laying. They belong to the society Eiffage TP. Eiffage has 22’000 workers and employees, 85 % of them in France. They exist since 1993, but their history begins in the year 1844 with the creation of the society Fougerolle.
The section lengths varied between 14–38 m (46-125 ft). For a 14 m (46 ft) long section they required around 8 working hours. One big advantage of the PIPe method is that new PP or PE pipes are pulled in. These new pipes have a lifetime of 60-80 years.
The manhole frame fits through the manhole opening Ø 620 mm (24.4“) and can be positioned into manholes Ø 800 mm (32“) and 1‘000 mm (40”).
The Cable Burster TERRA-EXTRACTOR X 400 is assembled via two support struts onto the manhole frame.
The calibre head Ø 295 mm (11.6“) is lifted down into the second manhole.
A short pipe is pulled in. This takes approximately 20 seconds.