A system for blocking rotation between a first tubular and a second tubular includes a key positioned within a recess formed in the first tubular. The system also includes a retention fastener securing the key to the first tubular, the retention fastener being arranged within an elongated aperture extending through the key. The system further includes an installation fastener moving the key from a storage configuration when in a first position to an engaged configuration when in a second position, the installation fastener having a tapered face that engages at least a portion of the key. The system also includes teeth arranged along a bottom portion of the key, proximate the second tubular, the teeth engaging the second tubular via rotation of the key about the retention fastener and blocking rotation of the first tubular relative to the second tubular in a first direction.

A polymeric device for protection of the connecting pipe coupling contains a stepped bushing having a medium part with an increased diameter and two lateral parts with a smaller outside diameters, which is installed between end faces of pipes with a conic thread, and connected by means of a coupling and having sealing rings made of an elastomer, which are on parts of the bushing with the small diameter. The device has an additional stepped bushing, and the first stepped bushing has a constant outside diameter and two parts with small and large internal diameters, and the second stepped bushing has a constant internal diameter and two parts with small and large diameters.

The galling resistance of a threaded joint for steel pipes which has a pin with triangular male threads and a box with triangular female threads which threadingly engage with the male threads and an unthreaded sleeve positioned at the end of the box is improved. The unthreaded sleeve is shortened or removed so that the length of the unthreaded sleeve in the axial direction of the box becomes at most ½ (including 0). The shape of the box may be modified by providing a swoosh portion at the end of the box and/or by making the bevel angle at the end of the female threads ±15 degrees of the flank angle of the female threads.

A leak-resistant pipe connection has an annular seal bulge on a pin end of the connection and a tapered seal area adjacent a secondary box shoulder of a box end of the connection. The annular seal bulge is coined on contact with the tapered seal area on initial make-up of the connection which provides a metal-to-metal seal that is very resistant to high-pressure fluid leakage even after the connection is subjected to extreme shear and tensile stresses.

A superhigh torsional strength, metallic and airtight drillrod coupler including an externally threaded coupler having a radially outward outer shoulder at an end thereof in an axial direction, an inner end face at the other end thereof in the axial direction, and a first sealing face being provided in sequence in the axial direction of the externally threaded coupler. The coupler further includes an internally threaded coupler to be threadedly connected to the externally threaded coupler, the internally threaded coupler having a radially inward inner shoulder at an end thereof in an axial direction, and an outer end face at the other end thereof in the axial direction, with a second sealing face. Further, the first sealing face and the second sealing face are both sloped faces, and are in an interference-fit sealed connection with each other.

A joint structure for steel pipes according to the invention includes a pair of steel pipes having male threads formed at end portions thereof, and a coupling having a pair of sets of female threads formed therein so that the male threads of the pair of steel pipes screw in the pair of the sets of female threads, respectively. Distal end surfaces at the end portions of the steel pipes have inner circumferential edges each protruding in a direction of a pipe axis with respect to outer circumferential edges thereof. When the pair of steel pipes are coupled to each other by the coupling and the inner circumferential edges of the distal end surfaces of the pair of steel pipes are brought into contact with each other, a gap is formed between the outer circumferential edges of the distal end surfaces of the pair of steel pipes.

A piping is provided with an RFID tag for identifying the piping, wherein the piping comprises a first end section for being coupled to a second piping and a second end section for being coupled to a third piping. The piping further comprises a mid-section in between the end sections. The RFID tag is provided in an elongate recess that is formed in the piping and that extends in a tangential direction parallel to a surface of the mid-section of the piping.

A threaded joint includes: a pin having an annular outer peripheral surface portion formed on a tip end side of a steel pipe, and an externally-threaded portion formed from the annular outer peripheral surface portion toward a center of a steel pipe in an axial direction of the steel pipe; and a box having a cavity in which the pin is housed, wherein an internally-threaded portion which threadedly engages with the externally-threaded portion and an annular inner peripheral surface portion which is brought into contact with and abuts against the annular outer peripheral surface portion are formed in the cavity, wherein the pin and the box are joined to each other due to threaded engagement between the externally-threaded portion and the internally-threaded portion.

A threaded joint is constructed of a pin and a box, the box having an outside diameter less than 104% of an outside diameter of a tubular body having the pin. The box includes, in order from an end of the box toward the tubular body: a lip portion and a female threaded portion, the lip portion including a shoulder surface and a sealing surface. The pin includes a shoulder surface, a sealing surface, and a male threaded portion. The lip portion of the box has a nose portion disposed between the shoulder surface and the sealing surface and an annular portion disposed between the sealing surface and the female threaded portion. The nose portion and the annular portion are not in contact with the pin, and a length of the annular portion is longer than a thread pitch of the female threaded portion.

A threaded connection connecting a pair of pipes includes a pin and a box. The pin has a male thread on its outer diameter. The box has a female thread on its inner diameter, the female thread corresponding to the male thread. The male thread includes constant-thread-width and varying-thread-width portions. The constant-thread-width portion has a constant thread-groove width. The varying-thread-width portion has a thread-groove width equal to or larger than the groove width of the constant-thread-width portion and gradually increasing, from the constant-thread-width portion toward the tip of the pin. The female thread includes constant-thread-width and varying-thread-width portions. The constant-thread-width portion has a constant thread-ridge width. The varying-thread-width portion has a thread-ridge width equal to or larger than the thread-ridge width of the constant-thread-width portion and gradually increasing from the constant-thread-width portion toward the center of the box.