Abstract: A high strength Wedgethread Pipe Connection having a ratio of the radius change per turn to the thread width change per turn, as is required to maintain both a thread seal and tightness, even when the connection is subjected to transient service loads such as vibrations, shock, bending, tension, compression, torsion and/or thermal changes. The thread form may be Open or Trapped for use on large or small diameter pipe, configured such as: a flush joint; with collars of larger diameter than the pipe; with double-pin couplings; tool and accessory connections; or it may also be used to reversibly connect such as solid structural posts to base members where a wide range of repeatable makeup torque is desired. The threads have provisions for ease of manufacture and assembly, and to minimize handling damage.

Abstract: Several embodiments of a wedgethread pipe connection are disclosed that have improved makeup, sealing and non-loosening characteristics. In one embodiment, an open wedgethread is disclosed that has an included angle measured in the gap between the stab flank and the load flank to be not less than zero, so as to prevent premature wedging between mating flanks before the position of full makeup is reached, as does occur between trapped wedgethreads wherein the included angle is less than zero.