Abstract: A tubular connector system for joining two pipe ends without the necessity of rotating the pipe ends. A coupling has opposing tapered ends. Each of the tapered ends slopes inwardly from an inner extent to an outer extent to form a respective mouth opening of the body. Each tapered end of the coupling has a contoured surface which is made up of a series of alternating helical spline wedges. The wedges are oppositely tapered from an inner extent to an outer extent, whereby the helical spline wedges form an alternating series of lands and grooves on the body as viewed from the respective mouth openings. The two opposing pipe ends have mating engagement surfaces which engage and mate with the contoured surfaces of the coupling as one pipe end is pushed toward the other during assembly.

Abstract: A thread form is shown which is used to make a threaded pipe connection capable of being screwed together and subsequently unscrewed. A pin member has external threads with stab flanks and load flanks and flat crests and roots for mating with the mating internal threads of a box member to make up a pipe connection. The stab flanks and load flanks form a distinct geometric profile which is arrow-shaped when viewed in profile. The arrow profile can be cut in either of two opposite directions. Each profile includes only two facets with the facets on the stab flank and the facets on the load flank both leaning in the same direction with respect to the longitudinal axis of the pipe, when viewed in profile.

Abstract: A thread form is shown which is used to make a threaded connection between two tubular members and which is capable of being screwed together and subsequently unscrewed. A pin member is provided having external threads with stab flanks and load flanks and flat crests and roots for mating with the mating internal threads of a box member to make up a pipe connection. The thread crests on the pin member are cylindrical with respect to a central longitudinal axis of the tubular member while the thread roots are cut on a taper so that the height of the threads vary over the length of the thread form. The threads on the pin and box members can also be cut oppositely so that respective members of the thread forms are mirror images of each other.

Abstract: A tubular connector system is disclosed for joining two pipe ends. The pipe ends are joined without the necessity of rotating the pipe ends. A special coupling has opposing tapered ends. Each of the tapered ends slopes inwardly from an inner extent to an outer extent thereof to thereby form a respective mouth opening of the body. Each tapered end of the coupling has a specially contoured surface which is made up of a series of alternating helical spline wedges. The wedges are oppositely tapered from an inner extent to an outer extent thereof, whereby the helical spline wedges form an alternating series of lands and grooves on the body as viewed from the respective mouth openings. The two opposing pipe ends have mating engagement surfaces which engage and mate with the contoured surfaces of the coupling as one pipe end is pushed toward the other during assembly.

Abstract: A threaded pipe connection is shown which features a pressure energized flex-seal structure. The connection includes a first box member having a box end, the box end having an end opening defining an interior surface with internal threads, the internal threads being defined by crests and roots and opposing flanks. A second, mating pin member has a pin end with a pin nose, the pin end having an exterior surface with mating external threads, the external threads also having crests and roots and opposing flanks, at least selected ones of which move into engagement with the internal threads of the box when the connection is made up. A flex-seal region is located on the box end interior surface which is designed to engage a cooperating energizing surface on the mating pin end to thereby form a primary containment seal upon make up of the connection.

Abstract: A thread form is shown which is used to make a threaded pipe connection capable of being screwed together and subsequently unscrewed. A pin is provided having external threads with stab flanks and load flanks and flat crests and roots for mating with the mating internal threads of a box to make up a pipe connection. The stab flanks and load flanks form complex geometric profiles which in one version form an inclined Z-shape in profile and in another version form a reverse inclined Z-shape profile. Each profile includes at least three separate facets with the facets on the stab flank and the facets on the load flank both leaning in the same direction with respect to the longitudinal axis of the pipe, when viewed in profile.

Abstract: A welded low carbon dual phase (ferrite plus martensite) and/or low carbon martensitic stainless steel PIPE having requisite yield strength and corrosion and/or erosion resistance is shown. Pipe can be manufactured up to a maximum outside diameter from finished plate or coil by utilizing a high speed-forming mill rather than using the traditional costly seamless pierced billet methods, or utilizing U-O-E or break press. An ERW technique is also used rather than utilizing the traditional laser, tungsten inert gas, gas metal arc, plasma arc, submerged arc or double submerged arc welding methods; or the parameters and procedures for ERW traditionally used to weld carbon steel pipe. Welded pipe dimensions and mechanical properties can be achieved which comply with the heat treatment process and the continuous roll forming mill's capability to produce the yield strengths and dimensional tolerances required to meet the service criteria of the pipe's intended application.