This paper provides an overview of the multiple case histories of the Direct Pipe technology in the US and overseas, including a 42″/48″ casing pipe installation by Michels Directional Crossings. Thereby illustrating the benefits for the owner, engineer and contractor in comparison to HDD in permeable soil conditions.
The Direct Pipe method has been first used in 2007 at the Rhine river crossing in Worms, Germany. Since then, more than 18 crossings have been installed in Europe and the US with great success. The longest installation so far had a total length of 4,600ft (1,400m) and a pipeline diameter of 48″. The peak performance during that installation was 756ft (232m) per day (24hrs).
The first installation in the US was in August 2010, crossing HI 70 in Florida. In 2011 the first 42″ system has been used at a project in Corning, NY by Michels Directional Crossings, for the installation of a casing pipe for a 24″ HDD crossing.
Laney Directional Drilling followed in early 2013 with the first 48″ Direct Pipe system being operated in North America at the Aquashicola crossing for Williams Pipelines in Monroe county, Pennsylvania.
August 2013 Direct Pipe made its debut in Canada at the Beaver River Crossing for Inter Pipeline Fund north of Bonnyville, Alberta.
The largest pipeline currently installed is a 56″ steel pipe in Preston, England with a total length of 2,820ft, serving as casing pipe for a post installed 36″ potable water pipeline (HDPE).
The combination of the well established Microtunneling technique with the Pipe Thruster technology makes it ideal for difficult (permeable) soil conditions which pose a certain risk for frack-outs using the HDD method.