Environmental & Foundation Drilling Inc. recently utilized its rig's ability to drill steel casing into bedrock without the need for an enlarged borehole and grout.
EFD proposed to set up its Barber DR 24 rig on a series of barges that could be adjusted to obtain an opening for advancement of the drill stem. A Barber DR drill has two separate rotary drives. There is an outward pivoting tophead that has the ability to turn standard drill pipe, as well as dual tube applications. The lower drive is a large hydraulic ring gear that clamps onto steel casing. The lower drive cannot only spin the casing in the ground, it also advances the casing using down pressure. Drill rods and steel casings are loaded from the rear using the outside pivoting tophead, along with the assistance of a winch or crane behind the rig.