A drill pipe comprises a drill pipe body and a tool joint that comprises a rotary shoulder connection is disclosed. The rotary shoulder connection comprises: a box connection, wherein the box connection has a box outer radius, a box counter bore radius and a box inner radius, and box threads having a box thread form cut along a box taper; a pin connection, wherein the pin connection has a pin outer radius, a pin cylinder radius and a pin nose radius, and pin threads having a pin thread form cut along a pin taper to align with the box threads inside the box connection; and a primary shoulder connection comprising: a primary box shoulder that is angled or curved; and a primary pin shoulder that is angled or curved. Methods of using the drill pipe are also disclosed.

Threaded joint, comprising a first and a second tubular component (C1, C2), the first tubular component comprising a first pipe body (10) and a male end (1), the male end comprising a distal surface (17) and a male threaded zone (13) at a male end, the second tubular component comprising a second pipe body (20) and a female end (2) comprising a distal surface and a female threaded zone (23), both male and female threaded zones (13, 23) comprising respectively a varying zone where thread have varying width, and a non varying zone, adjacent to the varying zone, where thread have a constant width, the varying zone of the male threaded zone being made up with the varying zone of the female threaded zone, and non varying zone of the male threaded zone being made up with the non varying zone of the female threaded zone, a thread profile of the male and female threaded zones being trapezoidal and a pin external shoulder (37) of the male end is in axial abutting contact against a corresponding abutment surface (42) of the female distal surface.

A tubular connection comprising a longitudinal axis, a pin member comprising a distal pin end, a tapered pin thread having a constant pin taper angle α.sub.1 with respect to the longitudinal axis, and a pin sealing surface located between the pin thread and the distal pin end, and a box member comprising a distal box end, a box sealing surface, and a tapered box thread having a constant box taper angle β.sub.1 with respect to the longitudinal axis and located between the box sealing surface and the distal box end, and wherein the pin thread is configured to cooperate by make up with the box thread along a cooperating area, while having a radial thread interference between the pin thread and the box thread along at least part of the cooperating area, the pin sealing surface and the box sealing surface are configured to contact each other upon make-up in a sealing manner while forming a metal to metal seal, and the pin taper angle α.sub.1 is larger than the box taper angle β.sub.1.

A directly connected drill pipe applicable to extreme conditions includes a tool joint pin and a tool joint box, where an external pipe section is located on an external side of a threaded section of the tool joint pin, and an annular groove is formed between the external pipe section and the threaded section of the tool joint pin. An insertion section of the tool joint box can be inserted into the annular groove in a matched manner. A main shoulder of the tool joint pin is located at an end of the external pipe section, a main auxiliary shoulder of the tool joint pin is located on a bottom surface of the annular groove, and an auxiliary shoulder of the tool joint pin is located at a small end of the tool joint pin. The tool joint box has three corresponding shoulders which form a 3-stage sealing with the tool joint pin.

An example fitting includes: a fitting body having counterbore, where the counterbore defines an annular shoulder within tire fitting body: a spring having a first end interfacing with the annular shoulder of the counterbore; and a seal carrier having: (i) a first end face interfacing with a second end of the spring, (ii) a second end face configured to interface with an internal surface of a port, such that the spring is configured to apply a biasing force on the seal carrier toward the internal surface of the port, (iii) a first annular groove on an exterior peripheral surface of the seal carrier, where the first annular groove is configured to have a radial seal disposed therein, and (iv) a second annular groove in the second end face, where the second annular groove is configured to have a face seal disposed therein.

A tubular connection includes a first joint of casing having an integral box end with an internal female wedge threaded zone having wedge threads disposed on a portion of the integral box end, and a second joint of casing having an integral pin end with an external male wedge threaded zone having wedge threads disposed on a portion of the integral pin end. The external male wedge threads engage with the internal female wedge threads. The second joint of casing has an internal diameter D1, and also includes an internal annular recess with an internal diameter D2. D2 is greater than D1, and the annular recess is disposed longitudinally along an inner surface of the second joint of casing. The annular recess is positioned radially adjacent to a portion of the external male threads disposed on a lower portion of the pin end.

A threaded connection includes a first tube having a pin, the pin having pin threads, a circumferential concave outer pin surface, and a pin torque shoulder at a free end, the concave outer pin surface including a pin seal surface and a continuous extension from the pin seal surface to the pin torque shoulder. A second tube has a box, the box has box threads for interacting with the pin threads, a circumferential inner box surface and a box torque shoulder. The inner box surface has a radially inwardly extending box seal surface, the pin seal surface contacts the box seal surface to define a seal. The seal is spaced from the free end when the pin and box torque shoulders contact, the continuous extension continuing from the seal to the pin torque shoulder. A method for making-up a threaded connection is also provided.

A threaded joint for casing pipes and production pipes has a threaded portion, and a metal-metal type sealing assembly structure in the form of a combination of sealing elements which provide 100% effective functioning of the joint under compression and tension, inter alia under the effect of internal and external fluid pressure, by observing the size ratio criteria of a ball-and-cone type seal, in which a radial sealing surface has two consecutively arranged toroidal surfaces which, in the event of axial contact between flanges, form, together with a mating sealing surface of a female member, two seals which remain tight under any combination of loads. The technical result of the group of inventions is an increase in the reliability of the threaded joint under the effect of static and variable operating loads, including external pressure, compression, twisting, and combined loads during the bending and turning of a pipe string, wherein the pipes can be used in the construction of wells having a degree of deviation of up to 13°/10 m.

A tubular connection includes a first joint of casing having an integral box end with an internal female wedge threaded zone having wedge threads disposed on a portion of the integral box end, and a second joint of casing having an integral pin end with an external male wedge threaded zone having wedge threads disposed on a portion of the integral pin end. The external male wedge threads engage with the internal female wedge threads. The second joint of casing has an internal diameter D1, and also includes an internal annular recess with an internal diameter D2. D2 is greater than D1, and the annular recess is disposed longitudinally along an inner surface of the second joint of casing. The annular recess is positioned radially adjacent to a portion of the external male threads disposed on a lower portion of the pin end.

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.