摘要 |
A drilling and hoisting system that mounts a rotating elevator, providing lift and rotation for a drill string, on a horizontal platform assembly, together with all necessary drive motors and ancillary pipe handling equipment. This platform is suspended from balanced dual crown blocks driven by a double drum draw works. This rotary elevator platform opens up the center of the drill rig for pipe handling. Pipe is handled by the elevator by gripping the pipe at a tool joint; the pipe stand may extend above the rotary elevator. A keyhole in the crown assembly of the drill rig passes the upper end of pipe stands to a light weight stand jib crane which racks pipe stands against a ground level pipe rack. The height of the rig mast no longer limits the maximum length of pipe stand which can be handled, and four section stands can be handled in a rig having a mast under 100 feet high.
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