20110083841 | DRILL PIPE - A drill pipe assembly includes an elongate drill pipe and a drill pipe extension. The elongate drill pipe has a first threaded end and a second threaded end. The drill pipe extension has a first threaded end and a second threaded end. The second threaded end matingly engaging the first threaded end of the elongate drill pipe. The first threaded end being adapted to matingly engage an additional component of a drill string. The drill pipe extension has an external upset. The external upset has recessed flow paths. | 04-14-2011 |