Abstract: A threaded tubular connection has a box member including an internal thread, a pin member including an external thread engageable with the internal thread of the box member, and a protruding sealing surface disposed in the box member such that the pin member flexes radially inward upon passing the protruding sealing surface during make-up. The threaded tubular connection also has a recessed seal cavity disposed in the box member and a reverse angle shoulder at the pin nose that forces the pin member to flex radially outward into the recessed seal cavity of the box member upon final make-up.

Abstract: A threaded connector includes a pin member having a large thread step and a small thread step. The pin member has a first sealing surface between the steps. Threads on the steps of the pin member each have load flanks and stab flanks. The connector includes a box member having a large thread step and a small thread step corresponding to the thread steps on the pin member. The box member has a second sealing surface corresponding to the first sealing surface. Threads on the steps of the box member have load flanks and stab flanks corresponding to the threads on the pin member. The threads on the large thread step have a first clearance between corresponding stab flanks on the pin and box members when the pin and box members are assembled and the corresponding load flanks are engaged. The threads on the small step have a second clearance between corresponding stab flanks when the pin and box members are assembled. The first clearance in one embodiment is smaller than the second clearance.

Abstract: A threaded pipe connection includes a box member and a pin member. The box member has multiple internal, generally dovetail-shaped threads, each with stab flanks, load flanks, roots, and crests. The pin member also has multiple external, generally dovetail-shaped threads, each with stab flanks, load flanks, roots, and crests. The internal threads of the box member each increase in width in one direction, while the external threads of the pin member increase in width in the other direction so that the complementary flanks of the respective threads move into engagement upon make-up of the connection.

Abstract: A threaded pipe connection is disclosed for connecting two joints of pipe having externally threaded pin members, one pin member having external right-hand threads and the other pin member having left-hand threads. An internally threaded coupling having right and left-hand threads that mates with the threads on the pin members. An internal pressure seal ring is positioned to provide a seal between the ends of the pin members. A plurality of mating lugs and grooves on the ends of the pin members hold the pins from relative rotation when the connection is being made up. A metal-to-metal seal located between each pin member and the coupling adjacent each end of the coupling isolates the threads of the connection from the ambient environment thus sealing off the pipe annulus from external pressure due to hydrostatic head.