Pipe ramming is a Trenchless method for installation of steel pipes and casings over distances usually up to 150 ft up long and up to 55-inches in diameter, although the method can be used for much longer and larger installations. Pipe Ramming is an excellent, cost efficient alternative for placing large diameter steel casing under roads, railroads, finished landscapes and structures. In cobble like materials, rammed pipe can swallow the material whole including large rocks and cobble, keeping the casing size to a minimum and saving cost on the job. In free flowing soil conditions the material is not removed until after the casing is placed, to reduce the risk of voids.

 

This method is pneumatic, i.e. it uses pneumatic percussive blows to drive the casing into the ground. The pneumatic tool is arranged on a launching pad with the nose of the tool placed inside a set of pipe collets that are fastened to the casing. The leading edge of the casing is almost always open to direct the soil into the casing interior instead of compacting it outside the casing. This helps to reduce friction between the pipe and soil and improve load conditions on the pipe. The leading edge of the casing is only closed when installing smaller diameters. Further reduction of friction is typically achieved with lubrication, and different types of bentonite and/or polymers can be used (as in horizontal directional drilling) for this purpose.