TORQUE SHOULDER FOR TUBULAR GOODS CONNECTION

TECHNICAL FIELD

This disclosure relates to a tubular good connection between tubular good joints, in particular, threaded tubular connections for tubular goods used in a wellbore.

BACKGROUND

Threaded tubular goods connections are used to couple joints of tubing together for use in a wellbore. A tubular goods connection couples a first tubular member with a box having an internal thread therein and a second tubular member with a pin having an external thread thereon.

Alternatively, a tubular goods connection couples a first tubular member having a threaded pin with a second tubular member with a pin having an external thread there using a coupling box connector having two boxes with mating internal threads disposed thereon.

A tubular goods connection can include a positive stop torque shoulder that acts as a load-bearing surface at the tubular goods connection.

SUMMARY

This disclosure describes roughened torque shoulders in threaded tubular good connections for tubular goods used in wellbores.

Certain aspects of the disclosure include a tubular connection including a first pin with an external male threaded zone having external male threads disposed on a portion of the pin, and a first box with an internal female threaded zone having internal female threads disposed on a portion of the first box. The internal female threads are to engage with the external male threads of the first pin, where at least one of the first pin or the first box includes a first torque shoulder surface having a surface roughness greater than or equal to 100 microns. The surface roughness may relate to the arithmetic average roughness (Ra). The term “micron” is used, but it is also referred to as micrometer (μm).

This, and other aspects, can include one or more of the following features. The surface roughness of the first torque shoulder surface can be between 100 microns and 500 microns. The first torque shoulder surface can include a knurled surface profile. The knurled surface profile can be continuous along the first torque shoulder surface. The first torque shoulder surface can include a laser cut, stamped, machined, or blasted surface profile. One of the first pin or the first box can include the first torque shoulder surface, and the other of the first pin or the first box can include a second torque shoulder surface, the second torque shoulder surface to engage the first torque shoulder surface. The second torque shoulder surface can include a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns). The second torque shoulder surface can include a knurled surface profile. The knurled surface profile can be continuous along the second torque shoulder surface. The second torque shoulder surface can include a laser cut, stamped, machined, or blasted surface profile. The first torque shoulder surface and the second torque shoulder surface can be at a respective one of a first longitudinal end of the first pin or a second longitudinal end of the first box. The first longitudinal end of the first pin can be a distal longitudinal end of the first pin, and the second longitudinal end of the first box can be a proximal longitudinal end of the first box. The first pin can include a third torque shoulder surface proximate to a third longitudinal end of the first pin opposite the first longitudinal end, the first box can include a fourth torque shoulder surface proximate to a fourth longitudinal end of the first box opposite the second longitudinal end, and at least one of the third torque shoulder surface or the fourth torque shoulder surface can include a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns), the fourth torque shoulder surface to engage the third torque shoulder surface. The at least one of the third torque shoulder surface or the fourth torque shoulder surface can include a knurled surface profile. The knurled surface profile can be continuous along the at least one of the third torque shoulder surface or the fourth torque shoulder surface. The tubular connection can further include a second pin with a second external male threaded zone having second external male threads disposed on a portion of the second pin, and a coupling box connector comprising the first box and a second box, the second box having an internal female threaded zone having internal female threads disposed on a portion of the second box, the internal female threads to engage with the external male threads of the second pin, where the first pin has the first torque shoulder surface, and the second pin has a second torque shoulder surface, and where the second torque shoulder surface is to engage the first torque shoulder surface of the first pin. The first torque shoulder surface can include a knurled surface profile. The knurled surface profile can be continuous along the first torque shoulder surface. The first torque shoulder surface can include a laser cut, stamped, machined, or blasted surface profile. The second torque shoulder surface can comprises a surface roughness greater than or equal to 100 microns, e.g. between 100 microns and 500 microns. The second torque shoulder surface can include a knurled surface profile. The knurled surface profile can be continuous along the second torque shoulder surface. The second torque shoulder surface can include a laser cut, stamped, machined, or blasted surface profile.

Certain aspects of the disclosure encompass a method for forming a tubular connection. The method includes providing a first pin with an external male threaded zone having external male threads disposed on a portion of the first pin, and providing a first box with an internal female threaded zone having internal female threads disposed on a portion of the first box, the internal female threads configured to engage with the external male threads of the first pin. One of the first pin or the first box has a first torque shoulder surface, and the other of the first pin or the first box has a second torque shoulder surface. The method also includes engaging, with the first torque shoulder surface, the second torque shoulder surface to form a tubular connection, at least one of the first torque shoulder surface or the second torque shoulder surface including a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns).

Some aspects of the disclosure encompass a method for forming a tubular connection. The method includes providing a first pin with an external male threaded zone having external male threads disposed on a portion of the first pin, the first pin having a first torque shoulder surface positioned proximate to a first longitudinal end of the first pin, and providing a second pin with an external male threaded zone having external male threads disposed on a portion of the second pin, the second pin having a second torque shoulder surface positioned proximate to a second longitudinal end of the second pin. At least one of the first torque shoulder surface or the second torque shoulder surface has a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns). The method also includes providing a coupling box connector having a first box with an internal female threaded zone having internal female threads disposed on a portion of the first box, the internal female threads to engage with the external male threads of the first pin, and having a second box with an internal female threaded zone having internal female threads disposed on a portion of the second box, the internal female threads to engage with the external male threads of the second pin. The method further includes engaging the external male threads of the first pin with the internal female threads of the first box, engaging the external male threads of the second pin with the internal female threads of the second box, and engaging the first torque shoulder surface with the second torque shoulder surface.

Certain aspects of the disclosure encompass a method for forming a pin or a box for a tubular connection. The method includes providing a pin or box having a first torque shoulder surface, and modifying the first torque shoulder surface to have a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns).

This, and other aspects, can include one or more of the following features. Modifying the first torque shoulder surface can include at least one of knurling, laser cutting, stamping, machining, or blasting the first shoulder surface to the surface roughness of greater than or equal to 100 microns (e.g. between 100 microns and 500 microns).

Certain aspects of the disclosure encompass a tubular connection including a first tubular good joint. The first tubular good joint includes an integral threaded end including a threaded zone having threads disposed on a portion of the integral threaded end, and a first torque shoulder surface, where the first torque shoulder surface includes a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns).

This, and other aspects, can include one or more of the following features. The integral threaded end can be an integral box, the threaded zone can be an internal female threaded zone, and the threads can be female internal threads. The integral threaded end can be an integral pin, the threaded zone can be an external male threaded zone, and the threads can be male external threads. The tubular connection can further include a second tubular good joint including an integral box, where the integral box can include an internal female threaded zone having internal female threads disposed on a portion of the integral box, the internal female threads to engage with the external male threads, and a second torque shoulder surface, the second torque shoulder surface to engage the first torque shoulder surface of the first tubular good joint. The second torque shoulder surface can include a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns). The second torque shoulder surface can include a knurled surface profile. The knurled surface profile can be continuous along the second torque shoulder surface. The second torque shoulder surface can include a laser cut, stamped, machined, or blasted surface profile. The first torque shoulder surface can include a knurled surface profile. The knurled surface profile can be continuous along the first torque shoulder surface. The first torque shoulder surface can include a laser cut, stamped, machined, or blasted surface profile.

Some aspects of the disclosure encompass a tubular joint including a pin with an external male threaded zone having external male threads disposed on a portion of the pin, the pin having a torque shoulder surface having a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns).

Some aspects of the disclosure encompass a tubular joint including a box with an internal female threaded zone having internal female threads disposed on a portion of the box, the box having a torque shoulder surface comprising a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns).

Some aspects of the disclosure encompass a coupling box connector including a box with an internal female threaded zone having internal female threads disposed on a portion of the box, the box including a torque shoulder surface having a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns).

Some aspects of the disclosure encompass a torque shoulder surface for a pin or a box of a tubular connection, the torque shoulder surface having a surface roughness greater than or equal to 100 microns (e.g. between 100 microns and 500 microns).

The details of one or more implementations of the subject matter described in this disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the subject matter will become apparent from the description, the drawings, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial cross-sectional perspective view of a first example tubular goods connection.

FIG. 2A is a schematic cross-sectional side view of a box of the tubular goods connection of FIG. 1.

FIG. 2B is a schematic cross-sectional side view of a pin of the tubular goods connection of FIG. 1.

FIGS. 3A and 3B are partial schematic cross-sectional side views of the example tubular goods connections of FIG. 1.

FIGS. 4A and 4B are partial schematic cross-sectional side views of example tubular goods connections.

FIG. 5 is a partial top perspective view of the box of FIG. 2A.

FIG. 6 is a graph showing a torque curve over rotations (or turns, n) for a conventional tubular goods connection versus a tubular goods connection with a roughened torque shoulder.

FIG. 7A is a flowchart describing an example method for forming a threaded tubular connection.

FIG. 7B is a flowchart describing an example method for forming a threaded tubular connection.

FIG. 8 is a flowchart describing an example method for forming a tubing joint.

FIG. 9 is a partial cross-sectional perspective view of a second example tubular goods connection.

FIG. 10A is a schematic cross-sectional side view of a box of the tubular goods connection of FIG. 9.

FIG. 10B is a schematic cross-sectional side view of a pin of the tubular goods connection of FIG. 9.

FIG. 11 is a partial top perspective view of the box of FIG. 10A.

FIG. 12A is a schematic cross-sectional side view of a third example tubular goods connection.

FIG. 12B is an enlarged schematic cross-sectional side view of the example tubular goods connection of FIG. 12A.

Like reference numbers and designations in the various drawings indicate like elements.

DETAILED DESCRIPTION

Certain terms are used herein as they would be conventionally understood in the tubular goods industry, particularly where threaded tubular goods are connected in a longitudinal (e.g., vertical) position along their respective central axis such as when making up a tubular goods string for lowering into a wellbore. Typically, in a male-female threaded tubular goods connection, the male component of the connection is referred to as a “pin” member at a pin and the female component is called a “box” member. In certain implementations, a first pin and a second pin can be connected with a coupling box connector. A coupling box connector is a tubular element having a box at each end thereof.

This disclosure describes tubular good connections between threaded tubular good joints, where one or both of pin and box of the tubular good joints or the coupling box connector includes a torque shoulder (i.e., positive-stop torque shoulder) with a roughened shoulder surface. The shoulder surface of the torque shoulder is also referred to as torque shoulder surface. The torque shoulder surface is mechanically roughened, for example, via knurling or other mechanical manipulation, such that its surface roughness is increased. The roughened surface of the torque shoulder can increase torque at a tubular goods connection, which can provide improved securement and hold of the tubular good connection, and an increased break-out torque of the tubular good connection. The roughened shoulder surface in a tubular good connection can increase an operative torque of the connection due to the engagement of the roughened torque shoulder with a corresponding abutment surface. A tubular good connection is formed between a threaded tubular good joint and a corresponding tubular good joint or connector (e.g., coupling box connector), where corresponding threading and corresponding torque shoulders provide load bearing surfaces in the made-up tubular good connection. For example, a tubular good joint includes threading (for example, radially external male threading, or radially internal female threading) and a torque shoulder with a roughened surface. The torque shoulder surface is roughened by knurling, laser cutting, stamping, machining, blasting, a combination of these, or other surface roughening technique, so that the surface roughness of the torque shoulder is greater than or equal to 100 microns (e.g., between 100 microns and 500 microns). The surface roughness relates to the arithmetic average roughness (Ra). The term “micron” is used, but it is also referred to as micrometer (μm).

In some conventional threaded tubular good joints, torque shoulder surfaces of respective tubular good joints are typically smooth, for example, with a surface roughness of less than 40 microns. Some conventional torque shoulder surfaces typically maintain a default, post-machined roughness when the respective tubular good joint is manufactured and machined. This default roughness is less than 40 microns, such as 10 to 40 microns. In this disclosure, at least one torque shoulder of a tubular good connection includes a roughened surface with a surface roughness greater than 100 microns (for example, via knurling, laser cutting, stamping, machining, blasting, or other technique). In some implementations, the surface roughness is achieved by mechanical manipulation of the shoulder surface, as opposed to a chemical treatment to a surface, to increase the surface roughness of the shoulder surface. The roughened surface can be easier to apply and be applied in a shorter amount of time than alternatives using a chemical or solvent. For example, the surface roughness of the present disclosure can be applied in a matter of seconds (e.g., 4 to 8 seconds), have a high accuracy of consistent and reliable roughness values, and can have little to no impact on health and the environment. These characteristics are advantageous over chemically-applied roughening techniques, for example, which can be difficult to apply, are less accurate, and can have a harmful impact on health and environment (depending on solvent and solid particles used) as compared to the present disclosure.

Referring now to FIG. 1, an example tubular goods connection 100 is shown in a partial cross-sectional perspective view. The example tubular goods connection 100 includes a first (lower) tubular member 400 with a pin 402 at an end, a coupling box connector 300 with a first box 301 at a first end and a second box 302 at a second end, and a second (upper) tubular member 200 with a pin 202. FIG. 1 shows the example tubular goods connection 100 as a buttress thread connection; however, the type of tubular connection can be different, as described in more detail later.

The first box 301 of the coupling box connector 300 is configured to engage with and seal to the pin 402 of the first tubular member 400, and the second box 302 of the coupling box connector 300 is configured to engage with and seal to the pin 202 of the second tubular member 200 to form the connection 100. In the example connection 100 of FIG. 1, the coupling box connector 300, the first tubular member 400, and the second tubular member 200 form a portion of a casing configured for implementation in a wellbore. However, the coupling box connector 300, the first tubular member 400 and second tubular member 200 can form a portion of another type of tubing. FIG. 2A is a cross-sectional side view of the box 302 at one end of the coupling box connector of FIG. 1 shown separately. FIG. 2B is a cross-sectional side view of the pin 202 at the end of the second tubular member 200 of FIG. 1 shown separately.

As illustrated in FIG. 2A, the coupling box connector 300 includes an internal thread 304 disposed along a portion of (e.g., an internal threaded zone of) the box 302, and includes a first torque shoulder 306 proximate to a proximal longitudinal end of the box 302. With respect to central axis A-A of FIG. 2A, the box 302 includes a distal longitudinal end at a (vertically) upper end of the box 302, and includes the proximal longitudinal end at a (vertically) lower end of the box 302 opposite the distal end. The first torque shoulder 306 includes a shoulder surface 315, or load bearing surface, that can engage (e.g., contact) a corresponding load bearing surface of the second tubular member 200 when the coupling box connector 300 and the second tubular member 200 are made-up to form the example connection 100. The shoulder surface 315 of the first torque shoulder 306 is also referred to as the first torque shoulder surface. The first torque shoulder 306 forms a ring shape around the inner cylindrical diameter of the box 302. The ring shape of the first torque shoulder 306 can be continuous around an entire circumference of the ring shape. However, in some instances, the ring shape can be non-continuous, or segmented. In some instances, the torque shoulder 306 can have a flat surface profile, a tapered conical surface profile, or a combination of both, with respect to a radial of the coupling box connector 300.

As illustrated in FIG. 2B, the second tubular member 200 includes an external thread 204 disposed along a portion of (e.g., an external threaded zone of) the pin 202, and a second torque shoulder 206 proximate to a distal longitudinal end of the pin 202. With respect to central axis A-A of FIG. 2B, the pin 202 includes the distal longitudinal end at a (vertically) lower end of the pin 202, and includes a proximal longitudinal end at an upper end of the pin 202 opposite the distal end. The second torque shoulder 206 includes a shoulder surface 215, or load bearing surface, that can engage (e.g., contact) the shoulder surface 315 of the first torque shoulder 306 of the coupling box connector 300 when the pin 202 and box 302 are fully engaged. The shoulder surface 215 of the second torque shoulder 206 is also referred to as the second torque shoulder surface. The second torque shoulder 206 forms a ring shape around the cylindrical diameter of the pin 202 at the distal end of the second tubular member 200. The ring shape of the second torque shoulder 206 can be continuous around an entire circumference of the ring shape. However, in some instances, the ring shape can be non-continuous, or segmented. In some instances, the torque shoulder 206 can have a flat surface profile, a tapered conical surface profile, or a combination of both, with respect to a radial of the coupling box connector 300.

As mentioned earlier, the torque shoulder 206, torque shoulder 306, or other torque shoulder of the connection 100 can have a varying profile shape. FIGS. 1-2B show the torque shoulders 206 and 306 as having a substantially flat surface profile that is (substantially or exactly) perpendicular to center longitudinal axis A-A. However, this surface profile shape can vary. For example, the surface profile of any of the torque shoulders of the connection 100 can include a slanted surface profile (i.e., that is angularly offset from a perpendicular of the longitudinal axis A-A), a jagged surface profile, a tapered surface profile with a rounded or pointed longitudinal end, a conical surface profile, a chamfered surface profile, a combination of these surface profiles, or another surface profile shape. In some examples, the torque shoulder surface can have a surface profile that is a combination tapered profile.

The shoulder surface 315 of the first torque shoulder 306, the shoulder surface 215 of the second torque shoulder 206, or both the shoulder surfaces 315, 215 of the first torque shoulder 306 and the second torque shoulder 206 can have a surface roughness greater than a minimum threshold roughness, such as 100 microns. The surface roughness of one or more of the shoulder surfaces increases a sliding frictional force of surfaces abutting the one or more shoulder surfaces. The surface roughness can be attained in a variety of ways, such as by knurling, laser cutting, stamping, machining, blasting, a combination of these, or another surface roughening technique (mechanical or other), so that the surface roughness of the respective shoulder surface is greater than or equal to 100 microns, such as between 100 microns and 500 microns. For example, FIG. 5 is a partial top perspective view of the example coupling box connector 300 with the box 302 showing the shoulder surface 315 of the first torque shoulder 306. As shown in FIG. 5, the shoulder surface of the first torque shoulder 306 includes knurling 308 in the form of slanted lines arranged continuously along an entirety of the shoulder surface. The example knurling 308 of FIG. 5 provides a surface roughness of the shoulder surface that is at least 100 microns, for example, between 100 microns and 500 microns. While FIG. 5 shows the knurling as including a slanted-line pattern that provides a sequence of peaks and valleys that create the surface roughness, the knurling can take a variety of other forms. For example, the knurling can include a straight pattern, angular pattern, diamond pattern, bubble pattern, or other knurling pattern types with a varying pitch and/or coarseness. Furthermore, while FIG. 5 shows the roughening, in particular the knurling, according to the invention on the shoulder surface of the torque shoulder 306 of the box 302, additionally or alternatively, the roughening, in particular the knurling, with the same or a different pattern, may be provided on the shoulder surface of the second torque shoulder 206 of the pin 202

To form the example connection 100, the integral pin 202 of the second tubular member 200 is inserted into the box 302 of the coupling box connector 300 to engage the corresponding threading and the corresponding torque shoulders. When the integral pin 202 of the second tubular member 200 is inserted into the box 302 of the coupling box connector 300 and the second tubular member 200 is rotated, the external thread 204 and the internal thread 304 threadingly engage (e.g., corresponds to and mate) to form the tubular goods connection 100. As the integral pin 202 is rotated relative to the box 302 toward a maximum rotation for complete engagement, the respective torque shoulder surfaces approach and abut each other. Upon a complete rotational installment of the pin 202 with the box 302, the shoulder surface 315 of the first torque shoulder 306 engages with (e.g., contacts, or abuts) the shoulder surface 215 of the second torque shoulder 206. FIG. 3A is a partial schematic cross-sectional side view of the example tubular connection 100 of FIGS. 1-2B. FIG. 3B shows in detail the coupling of the integral pin 202 of the second tubular member 200 and the box 302 of the coupling box connector 300. This coupling of the coupling box connector 300 and the second tubular member 200 is referred to in the art as making-up the tubular goods connection 100. When the tubular goods connection 100 is made-up, the internal thread 304 engages the external thread 204 via an interference fit of mating threads, and the first torque shoulder 306 engages (i.e., contacts) the second torque shoulder 206 via an interference fit of the contacting shoulder surfaces 315, 215. In some implementations, the internal thread 304 sealingly engages the external thread 204, for example, along all or a portion of the internal and/or external threaded zones. Alternatively or additionally, sealing of the connection is provided by an elastomeric seal or a so-called metal-to-metal seal. Examples of connections with a metal-to-metal seal in combination with torque shoulder surfaces are illustrated in U.S. Patent Publication No. US2004/0108719 to Carcagno et al., incorporated herein by reference in its entirety.

As used herein, “make-up” or in the past tense “being made up” refers to the procedure of inserting into and engaging the pin 202 of the second tubular member 200 with the box 302 of the first tubular member 300, and screwing the members together through torque and rotation to obtain a “made-up connection” where the respective threadings engage each other and the respective torque shoulders engage each other. In some implementations, the surface roughness of one or more shoulder surfaces of the torque shoulders provides an increased resistance to jump-out, or break-out, during use (i.e., increases break-out torque to disconnect the example connection). The use of the threaded connection in combination with the roughened torque shoulders can be used in applications (such as downhole wellbore operations) where additional torque is required, such as in horizontal wells, deviated wells, or other wellbore locations. In certain implementations, the additional torque gained from the roughened torque shoulders allows for less torque to be required by the respective mating threads of the connection. For example, the roughened torque shoulders can be implemented in thin-walled pipes where the radial dimension of the abutment surface is shorter than in thick-walled pipes. In other words, utilizing roughened torque shoulders provides an amount of torque to the tubular goods connection that allows for the use of a casing or tubing with thinner walls with shorter threaded zones, since the roughened torque shoulders and the shorter threaded zones still provides sufficient minimum torque (i.e., minimum operative torque) to the tubular goods connection.

FIGS. 1-3B show the torque shoulders 206 and 306 as having a substantially flat surface profile that is (substantially or exactly) perpendicular to center longitudinal axis A-A. However, this surface profile shape can vary. For example, the surface profile of any of the torque shoulders of the connection 100 can include a slanted surface profile (i.e., that is angularly offset from a perpendicular of the longitudinal axis A-A), a jagged surface profile, a tapered surface profile with a rounded or pointed longitudinal end, a conical surface profile, a chamfered surface profile, a combination of these surface profiles, or another surface profile shape. A variant of the example tubular connection 100 is illustrated in FIG. 4A. In FIG. 4A, a partial schematic cross-sectional side view of an example tubular connection 100′ is shown that corresponds to the example tubular connection 100 shown in FIG. 3B, except that the torque shoulders 206′ and 306′ of the connection 100′ include a slanted surface profile that is angularly offset from a perpendicular of the longitudinal axis A-A. In some instances, the coupling box connector 300, the second tubular joint 200, or both the coupling box connector 300 and the second tubular joint 200 include a torque shoulder on both longitudinal ends of the respective box 302 or pin 202. For example, FIG. 4B is a partial schematic cross-sectional side view of an example tubular connection 100″. The example tubular connection 100″ of FIG. 4B is similar to the example tubular connection 100′ of FIG. 4A, except the coupling box connector 300″ includes two torque shoulders on opposite longitudinal ends of the box 302″, and the second tubular good joint 200″ includes two torque shoulders on opposite longitudinal ends of the pin 202″. In the example connection 100″ of FIG. 4B, the coupling box connector 300″ includes the first torque shoulder 306′ on the proximal longitudinal end of the box 302″, and further includes a third torque shoulder 310 at the distal end of the box 302′. The second tubular good joint 200″ includes the second torque shoulder 206′ on the distal longitudinal end of the pin 202″, and further includes a fourth torque shoulder 210 on the proximal longitudinal end of the pin 202″. The third torque shoulder 310 includes a shoulder surface 325, and the fourth torque shoulder 210 includes a shoulder surface 225. The shoulder surface 325 of the third torque shoulder 310 is also referred to as the third torque shoulder surface. The shoulder surface 225 of the fourth torque shoulder 210 is also referred to as the fourth torque shoulder surface. The shoulder surface 325 of the third torque shoulder 310 can engage (e.g., contact) the shoulder surface 225 of the fourth torque shoulder 210 when the pin 202″ and box 302″ are fully engaged. One or more or all of the shoulder surfaces 315′, 215′, 325, 225 of the first torque shoulder 306′, second torque shoulder 206′, third torque shoulder 310, or fourth torque shoulder 210 can have a surface roughness greater than the minimum threshold roughness (e.g., 100 microns), as described earlier.

The third torque shoulder 310 forms a ring shape about the central axis A-A on the box 302″, and the ring shape of the third torque shoulder 310 can be continuous around an entire circumference of the ring shape. However, in some instances, the ring shape can be non-continuous, or segmented. Similarly, the fourth torque shoulder 210 forms a ring shape about the central axis A-A on the pin 202″, and the ring shape of the fourth torque shoulder 210 can be continuous around an entire circumference of the ring shape. However, in some instances, the ring shape can be non-continuous, or segmented. As described earlier, the surface profile of the torque shoulder 310 can vary. For example, the torque shoulder 310 can have a flat surface profile, a tapered conical surface profile, or a combination of both, with respect to a radial of the coupling box connector 300″.

Although herein above, under reference to FIGS. 1, 2A to 3B, and 5, the coupling between one box 302 at one end of the coupling box connector 300 and the pin 202 of the second tubular member 200 has been described, the same applies to the coupling between the other box 301 at the other end of the coupling box connector 300 and the pin 402 of the first tubular member 400. The same apples to connection 100′ of FIG. 4A and connection 100″ of FIG. 4B.

The coupling box connector 300 includes a radially inward flange 307 between the first box 301 and the second box 302 that can abut and engage shoulder surface 406 of the pin 402 of the first tubular member 400 and shoulder surface 206 of the pin 202 of the second tubular member 200.

Referring to the tubular goods connection 100 of FIGS. 1 to 3B and 5 (or connection 100′ of FIG. 4A and connection 100″ of FIG. 4B), the first tubular member 400 can be a first joint of casing 400 (or joint of tubing) having the pin 402 and the external male thread 404 disposed longitudinally on a portion of the pin 402. The external thread 404 is configured to sealingly engage with the internal female thread 305 of the box 301 of the coupling box connector 300. The second tubular member 200 can be a second joint of casing 200 (or joint of tubing) having the pin 202 with external male threading 204 disposed longitudinally on a portion of the pin 202. The external thread 204 is configured to sealingly engage with the internal female thread 304 of the box 302 of the coupling box connector 300. The second joint of casing 200 has an internal diameter D1 of an inner surface of the second joint of casing 200 that can be the same as an internal diameter of an inner surface of the first joint of casing 400. The tubular connection 100 can be made up to connect the first tubular good joint 400 and the second tubular good joint 200 to the coupling box connector 300.

Referring to the geometry of threads, the following is a brief discussion of standard industry terminology. For example, the term “load flank” designates the sidewall surface of a thread that faces away from the outer end of the respective pin or coupling member on which the thread is formed and supports all or a portion of the weight (i.e., tensile load) of the lower tubular member hanging in the wellbore. Similarly, the term “stab flank” designates the sidewall surface of the thread that faces toward the outer end of the respective pin or coupling member and supports forces compressing the joints toward each other such as the weight of the upper tubular member during the initial make-up of the joint.

Vanishing threads: The portion at the end of the threaded portion in a threaded connection, in which threads are not cut full depth, but which provides a transition between full formed threads and pipe body. Theoretically, the vanishing point is the point in which the tapered pitch diameter of the thread intersects the outside pipe diameter (“OD”).

Additionally, a thread “lead” refers to the differential distance between components of a thread on consecutive threads. As such, the “stab lead” is the distance between stab flanks of consecutive thread pitches along the axial length of the connection. A “load lead” is the distance between load flanks of consecutive thread pitches along the axial length of the connection.

FIG. 6 is a graph of an example torque curve 600 showing the torque of a tubular joint connection over rotations (or turns, n), more particularly, for a first, conventional tubular goods connection versus a tubular goods connection with a roughened torque shoulder. Torque plot 602 shows an example torque curve for an example conventional tubular good connection (first connection), for example, that excludes a roughened torque shoulder. The torque plot 602 shows the example torque curve of making up a pin and a box for an example conventional tubular good connection. Torque plot 604 shows an example torque curve for an example tubular good connection (second connection) that includes a roughened torque shoulder, for example, such as example tubular good connection 100, 100′, 100″, as described earlier. The torque plot 604 shows the example torque curve of making up a pin and a box, e.g. pin 202 of the second tubular member 200 and second box 302 of coupling box connector 300. The same example torque curve could be for making up the pin 402 of the first tubular member 400 and the first box 301 of the coupling box connector 300.

The torque curve 600 shows the torque of the respective tubular good connection between an initial point of contact (where respective threads of the connection begin to engage each other) and a final position of the connection (where the respective threads and respective torque shoulders of the connection are fully engaged). As described in more detail later, the torque plots 602 and 604 include a starting point, an inflection point (where corresponding torque shoulders begin to contact each other), and a final, fully made-up point.

Point 602a of torque plot 602 indicates the starting point for the make-up operation of the first tubular good connection. Point 602b is referred to as the “shouldering torque,” and indicates the instance where a torque shoulder of a box of the connection abuts (i.e., first contacts) a torque shoulder of a pin of the connection. Point 602c indicates the first operative torque 606 of the first connection, which refers to a torque value provided by the first connection when fully made-up (i.e., the end of the fastening operation between the pin and the box of the first connection). The operative torque can be provided by a manufacturer of the connection,

Point 604a of torque plot 604 indicates the starting point for the make-up operation of the second tubular good connection. Point 604b is the shouldering torque of the second connection, and indicates the instance where the torque shoulder with a roughened shoulder surface of a first tubular good joint of the second connection abuts (i.e., first contacts) a corresponding torque shoulder of a second tubular good joint of the second connection. Point 604c indicates the second operative torque 608 of the second connection, which refers to the torque value provided by the second connection when fully made-up (i.e., the end of the fastening operation between the first tubular good joint and the second tubular good joint of the second connection).

In the example torque curve 600 of FIG. 6, the torque plots 602 and 604 are representative of the first connection and the second connection having the same size threading, same location of respective torque shoulders, and other similarities, with the only primary difference being that the second connection (torque plot 604) includes a roughened shoulder surface (e.g., surface roughness greater than or equal to 100 microns), whereas the first connection has a conventional shoulder surface (e.g., surface roughness of about 20 microns).

The difference in the torque values at point 602b and at point 602c (torque at 602b subtracted by torque at 602c) is referred to as “delta torque” for the first connection. Similarly, the difference in the torque values at point 604b and at point 604c (torque at 604b subtracted by torque at 604c) is referred to as delta torque for the second connection. The segment of torque plot 602 between points 602a and 602b represents the gradual increase in torque of the first connection as corresponding threads are engaging. In this segment between 602a and 602b, the main resistance to the application of torque is the radial interference exerted by radial surfaces in contact with each other. Similarly, the segment of torque plot 604 between points 604a and 604b represents the gradual increase in torque of the second connection as corresponding threads are engaging. In this segment between 604a and 604b, the main resistance to the application of torque is the radial interference exerted by radial surfaces in contact with each other. As shown in the example torque curve 600, the segment between 602a and 602b and the segment between 604a and 604b are (substantially or exactly) the same.

Points 602b and 604b are inflection points in the respective torque plots, where torque more steeply increases as the turns increase. The segment of torque plot 602 between points 602b and 602c shows the sharp increase in torque caused by the energization of the abutment shoulders of the first connection. The torque value drastically increases in a fraction of a turn compared to the preceding segment between points 602a and 602b, for example, because axial interference is overcome, which consumes the corresponding torque energy that is stored as elastic energy in the first connection.

The segment of torque plot 604 between points 604b and 604c show a sharp increase in torque caused by the energization of the abutment shoulders of the second connection. This segment between 604b and 604c of torque plot 604 is steeper and reaches a higher operative torque 608 than the segment between 602b and 602b of torque plot 602, for example, because the surface roughness of the torque shoulder of the second connection provides an increased friction between the abutted shoulder surfaces, thereby increasing the torque energy that is stored as elastic energy in the second connection. As a result, the operative torque 608 of the second connection is greater than the operative torque 606 of the first connection, and the delta torque of the second connection is larger than the delta torque of the first connection.

Generally, the delta torque can be a measure of the resistance of the connection to break out or undergo undesired unfastening. The delta torque of the second connection is larger than the delta torque of the first connection, so the second connection has a larger break-out torque, and has increased resistance to undesired unfastening, than the first connection. The value of the operative torque 608 of the second connection can be increased (from the first operative torque 606) without the risk to reach the material plastic limit 610 of the material (e.g., steel or other metal) that makes up the tubular good joints of the second connection. The surface modification (i.e., surface roughening) of the torque shoulder generates enhanced tribological properties of the contact surfaces of the torque shoulder, which promotes an advantageous redistribution of stresses and deformations in the connection.

FIG. 7A is a flowchart describing an example method 700 for forming a connection, such as the tubular goods connection 100 of FIGS. 1-3B, tubular goods connection 100′ of FIG. 4A, or tubular goods connection 100″ of FIG. 4B. At 702, a first pin is provided, the first pin including an external male threaded zone having external male threads disposed on a portion of the first pin. At 704, a first box is provided, the first box including an internal female threaded zone having internal female threads disposed on a portion of the first box. The internal female threads are to engage with the external male threads of the first pin, where one of the first pin and or the first box has a first torque shoulder surface, and the other of the first pin or the first box has a second torque shoulder surface. At 706, the second torque shoulder surface engages with the first torque shoulder surface to form a tubular connection, where at least one of the first torque shoulder surface or the second torque shoulder surface includes a surface roughness greater than or equal to 100 microns.

FIG. 7B is a flowchart describing an example method 720 for forming a tubular connection, such as the tubular goods connection 100 of FIGS. 1-3B, tubular goods connection 100′ of FIG. 4A, or tubular goods connection 100″ of FIG. 4B. At 722, a first pin with an external male threaded zone having external male threads disposed on a portion of the first pin is provided, the first pin having a first torque shoulder surface positioned proximate to a first longitudinal end of the first pin. At 724, a second pin with an external male threaded zone having external male threads disposed on a portion of the second pin is provided, the second pin having a second torque shoulder surface positioned proximate to a second longitudinal end of the second pin. At least one of the first torque shoulder surface or the second torque shoulder surface includes a surface roughness greater than or equal to 100 microns. At 726, a coupling box connector is provided, the coupling box connector having a first box with an internal female threaded zone having internal female threads disposed on a portion of the first box, the internal female threads configured to engage with the external male threads of the first pin, and having a second box with an internal female threaded zone having internal female threads disposed on a portion of the second box, where the internal female threads are configured to engage with the external male threads of the second pin. At 728, the external male threads of the first pin are engaged with the internal female threads of the first box. At 730, the external male threads of the second pin are engaged with the internal female threads of the second box. At 732, the first torque shoulder surface is engaged with the second torque shoulder surface.

FIG. 8 is a flowchart describing an example method 800 for forming a tubing joint such as the tubular joints 200, 200′, 200″, 400, or for forming a coupling box connector 300′, 300″ of FIGS. 1-5B. At 802, a pin or box is provided, the pin or the box having a first torque shoulder surface. At 804, the first torque shoulder surface is modified to have a surface roughness greater than or equal to 100 microns.

The tubular connections 100, 100′, and 100″ described herein above under reference to FIGS. 1 to 4B are so-called “threaded and coupled” connections, wherein a pin at an end of a first tubular joint and a pin at and end of a second tubular joint are coupled via a coupling box connector having a box at both ends thereof. Alternatively, a tubular connection in accordance with the present invention is a so-called “integral” connection, wherein an integral box at an end of a first tubular joint is coupled to an integral pin at an end of a second tubular joint. An example of a tubular connection in accordance with the present invention that is of the “integral” type, is described herein below under reference to FIG. 9.

Referring now to FIG. 9, an example tubular goods connection 1100 is shown in a partial cross-sectional perspective view. The example tubular goods connection 1100 includes a first (lower) tubular member 1300 with an integral box 1302, and a second (upper) tubular member 1200 with an integral pin 1202.

FIG. 9 shows the example tubular goods connection 1100 as a wedge thread connection; however, the type of tubular connection can be different. The thread profile can be a buttress profile such as in the example connections 100, 100′ and 100″ described herein above. Furthermore, the threaded connection can be other thread profiles that can be used in combination with a torque shoulder.

Examples of connections with a wedge thread profile in combination with a torque shoulder are illustrated in U.S. Patent Publication No. US2010/0181763 to Mallis et al., incorporated herein by reference in its entirety.

The box 1302 of the first tubular member 1300 is configured to engage with and seal to the pin 1202 of the second tubular member 1200 to form the connection 1100. In the example connection 1100 of FIG. 9, the first tubular member 1300 and second tubular member 1200 form a portion of a casing configured for implementation in a wellbore. However, the first tubular member 1300 and second tubular member 1200 can form a portion of another type of tubing. FIG. 10A is a cross-sectional side view of the first tubular member 1300 of FIG. 9 shown separately. FIG. 10B is a cross-sectional side view of the second tubular member 1200 of FIG. 9 shown separately.

As illustrated in FIG. 10A, the first tubular member 1300 includes an internal wedge thread 1304 disposed along a portion of (e.g., an internal wedge threaded zone of) the box 1302, and includes a first torque shoulder 1306 proximate to a proximal longitudinal end of the box 1302. With respect to central axis A-A of FIG. 10A, the box 1302 includes a distal longitudinal end at a (vertically) upper end of the box 1302, and includes the proximal longitudinal end at a (vertically) lower end of the box 1302 opposite the distal end. The first torque shoulder 1306 includes a shoulder surface 1315, or load bearing surface, that can engage (e.g., contact) a corresponding load bearing surface of the second tubular member 1200 when the first tubular member 1300 and the second tubular member 1200 are made-up to form the example connection 1100. The shoulder surface 1315 of the first torque shoulder 1306 is also referred to as the first torque shoulder surface. The first torque shoulder 1306 forms a ring shape around the inner cylindrical diameter of the box 1302. The ring shape of the first torque shoulder 1306 can be continuous around an entire circumference of the ring shape. However, in some instances, the ring shape can be non-continuous, or segmented. In some instances, the torque shoulder 1306 can have a flat surface profile, a tapered conical surface profile, or a combination of both, with respect to a radial of the tubular member 1300.

As illustrated in FIG. 10B, the second tubular member 1200 includes an external wedge thread 1204 disposed along a portion of (e.g., an external wedge threaded zone of) the pin 1202, and a second torque shoulder 1206 proximate to a distal longitudinal end of the pin 1202. With respect to central axis A-A of FIG. 10B, the pin 1202 includes the distal longitudinal end at a (vertically) lower end of the pin 1202, and includes a proximal longitudinal end at an upper end of the pin 1202 opposite the distal end. The second torque shoulder 1206 includes a shoulder surface 1215, or load bearing surface, that can engage (e.g., contact) the shoulder surface 1315 of the first torque shoulder 1306 of the first tubular member 1300 when the pin 1202 and box 1302 are fully engaged. The shoulder surface 1215 of the second torque shoulder 1206 is also referred to as the second torque shoulder surface. The second torque shoulder 1206 forms a ring shape around the cylindrical diameter of the pin 1202 at the distal end of the second tubular member 1200. The ring shape of the second torque shoulder 1206 can be continuous around an entire circumference of the ring shape. However, in some instances, the ring shape can be non-continuous, or segmented. In some instances, the torque shoulder 1206 can have a flat surface profile, a tapered conical surface profile, or a combination of both, with respect to a radial of the tubular member 1300.

As mentioned earlier, the torque shoulder 1206, torque shoulder 1306, or other torque shoulder of the connection 1100 can have a varying profile shape. FIGS. 9-10B show the torque shoulders 1206 and 1306 as having a substantially flat surface profile that is (substantially or exactly) perpendicular to center longitudinal axis A-A. However, this surface profile shape can vary. For example, the surface profile of any of the torque shoulders of the connection 1100 can include a slanted surface profile (i.e., that is angularly offset from a perpendicular of the longitudinal axis A-A), a jagged surface profile, a tapered surface profile with a rounded or pointed longitudinal end, a conical surface profile, a chamfered surface profile, a combination of these surface profiles, or another surface profile shape. In some examples, the torque shoulder surface can have a surface profile that is a combination tapered profile, such as illustrated in U.S. Pat. No. 9,752,710.

The shoulder surface 1315 of the first torque shoulder 1306, the shoulder surface 1215 of the second torque shoulder 1206, or both the shoulder surfaces 1315, 1215 of the first torque shoulder 1306 and the second torque shoulder 1206 can have a surface roughness greater than a minimum threshold roughness, such as 100 microns. The surface roughness of one or more of the shoulder surfaces increases a sliding frictional force of surfaces abutting the one or more shoulder surfaces. The surface roughness can be attained in a variety of ways, such as by knurling, laser cutting, stamping, machining, blasting, a combination of these, or another surface roughening technique (mechanical or other), so that the surface roughness of the respective shoulder surface is greater than or equal to 100 microns, such as between 100 microns and 500 microns. For example, FIG. 11 is a partial top perspective view of the example first tubular member 1300 with the box 1302 showing the shoulder surface 1315 of the first torque shoulder 1306. As shown in FIG. 11, the shoulder surface of the first torque shoulder 1306 includes knurling 1308 in the form of slanted lines arranged continuously along an entirety of the shoulder surface. The example knurling 1308 of FIG. 11 provides a surface roughness of the shoulder surface that is at least 100 microns, for example, between 100 microns and 500 microns. While FIG. 11 shows the knurling as including a slanted-line pattern that provides a sequence of peaks and valleys that create the surface roughness, the knurling can take a variety of other forms. For example, the knurling can include a straight pattern, angular pattern, diamond pattern, bubble pattern, or other knurling pattern types with a varying pitch and/or coarseness.

To form the example connection 1100, the integral pin 1202 is inserted into the integral box 1302 to engage the corresponding threading and the corresponding torque shoulders. When the integral pin 1202 of the second tubular member 1200 is inserted into the integral box 1302 of the first tubular member 1300 and the second tubular member 1200 is rotated, the external wedge thread 1204 and the internal wedge thread 304 threadingly engage (e.g., corresponds to and mate) to form the tubular goods connection 1100. As the integral pin 1202 is rotated relative to the integral box 1302 toward a maximum rotation for complete engagement, the respective torque shoulder surfaces approach and abut each other. Upon a complete rotational installment of the pin 1202 with the box 1302, the shoulder surface 1315 of the first torque shoulder 1306 engages with (e.g., contacts, or abuts) the shoulder surface 1215 of the second torque shoulder 1206. When the tubular goods connection 1100 is made-up, the internal wedge thread 1304 engages the external wedge thread 1204 via an interference fit of the mating wedge threads, and the first torque shoulder 1306 engages (i.e., contacts) the second torque shoulder 1206 via an interference fit of the contacting shoulder surfaces 1315, 1215. In some implementations, the internal wedge thread 1304 sealingly engages the external wedge thread 1204, for example, along all or a portion of the internal and/or external threaded zones.

Wedge threads, regardless of a particular type, increase in width W1, W2 in opposite directions on a pin member and a box member. In preferred embodiments, the threads have a dovetail wedge thread profile characterized by having a width of a tooth crest WTC wider than a width of teeth WTR, so it can also be said that both flanks, stab and load flanks, are negative. In some examples, the threads can take on other profiles and shapes.

Depending on the type of the wedge thread (interference type or clearance type), the wedging between flanks will be generated in different ways. The wedging effect generated on interference wedge threads is due to specific axial interference fit between mating load and stab flanks. Moreover, the wedging effect can also be achieved without this specific design interference (e.g. clearance wedge type) by, for example, thread drunkenness and/or radial interference, for example by radial interference between crests and roots.

Regardless of the type of the wedge thread, e.g. clearance wedge, or interference wedge, corresponding flanks come closer to each other (i.e., clearance decreases or interference increases) during make-up. Indeterminate make-up allows for the flank interference to be increased by increasing the make-up torque on the connection. This increased make up torque will produce some drawbacks because said increased make up torque will generate a higher general stress state due to the higher flank to flank interference that will lead to high contact pressures between sliding elements (during make-up), and also between assembly elements (e.g., at the end of make-up).

Depending on the type of the wedge thread, the wedging between flanks will be generated in different ways. The wedging effect generated on interference wedge threads is due to specific interference fit between at least part of mating load and stab flanks of at least part of the threaded portion.

An example making up of the connection 1100 is as follows. Internal thread of box 1302 has stab flanks, load flanks, roots, and crests. The thread increases in width progressively at a uniform rate in one direction substantially the entire helical length of thread. External thread of pin 1202 has stab flanks, load flanks, roots, and crests. The thread increases in width progressively at a uniform rate in the other direction substantially the entire helical length of thread. The oppositely increasing thread widths and the taper of threads, cause the complementary roots and crests of the respective threads to move into engagement during make-up of the connection 1100. Root and crest engagement is followed by the moving of complementary stab and load flanks into engagement upon make-up of the connection. The moving of complementary flanks, roots and crests into engagement forms sealing surfaces that resist the flow of fluids between the threads. The torque shoulder surfaces of the torque shoulders 1206 and 1306 move into engagement upon make-up of the connection. The torque shoulder engagement may occur simultaneously with the stab and load flanks moving into engagement. Alternatively, the stab and load flanks may move into engagement after root and crest engagement during make-up of the connection and followed by the torque shoulder surface engagement upon make-up of the connection. As an alternative, upon initial make-up the torque shoulder surfaces are at an axial distance from each other. The torque shoulder surfaces may then during use, i.e. in the well, engage in case torque applied to the connection exceeds the torque resistance of the wedge thread. The torque shoulder surfaces thus serve as a backup for over-torque conditions during use.

FIGS. 12A and 12B show a further variant of the example tubular connections of FIGS. 1 to 11. The example tubular connection 500 of FIGS. 12A and 12B is a threaded and coupled type connection similar to the example tubular connections 100, 100′ and 100″ shown in and described under reference to FIGS. 1 to 8, however the coupling box connector 502 of tubular connection 500 does not have a radially inward flange between the first box 504a and the second box 504b. Furthermore, the thread profile of the tubular connection 500 is a wedge profile like the thread profile of example connection 1100 of FIGS. 9 to 11.

FIG. 12A is a schematic cross-sectional side view of an example tubular good connection 500 with an example coupling box connector 502. FIG. 12B is an enlarged schematic cross-sectional side view of the example made-up tubular good connection 500 of FIG. 12A. The first box 504a of the coupling box connector 502 is configured to engage with and seal to the first pin 512 of the first tubular member 510, and the second box 504b of the coupling box connector 502 is configured to engage with and seal to the second pin 1522 of the second tubular member 520 to form the example connection 500. The coupling box connector 502 includes a first internal wedge thread 506a disposed along a portion of (e.g., a first internal wedge threaded zone of) the first box 504a, and includes a second internal wedge thread 506b disposed along a portion of (e.g., a second internal wedge threaded zone of) the second box 504b.

The first tubular member 510 includes a first external thread 514 disposed along a portion of (e.g., a first external wedge threaded zone of) the first pin 512, and a first torque shoulder 516 proximate to a distal longitudinal end of the first pin 512. With respect to central axis A-A of FIG. 12A, the first pin 512 includes the distal longitudinal end at a terminal end of the pin 512, and includes a proximal longitudinal end at an opposite longitudinal end of the pin 512 opposite the distal end. The first torque shoulder 516 includes a shoulder surface 515, or load bearing surface, that can engage (e.g., contact) a shoulder surface of the second tubular member 520. The shoulder surface 515 of the first torque shoulder 516 is also referred to as the first torque shoulder surface. The first torque shoulder 516 forms a ring shape around the cylindrical diameter of the pin 512 at the distal end of the first tubular member 510. The ring shape of the first torque shoulder 516 can be continuous around an entire circumference of the ring shape. However, in some instances, the ring shape can be non-continuous, or segmented. As described earlier, the surface profile of the torque shoulder 516 can vary. For example, the torque shoulder 516 can have a flat surface profile, a tapered conical surface profile, or a combination of both, with respect to a radial of the tubular member 510.

The second tubular member 520 includes a second external wedge thread 524 disposed along a portion of (e.g., a second external wedge threaded zone of) the second pin 522, and a second torque shoulder 526 proximate to a distal longitudinal end of the fourth pin 522. With respect to central axis A-A of FIG. 12A, the second pin 522 includes the distal longitudinal end at a terminal end of the pin 522, and includes a proximal longitudinal end at an opposite longitudinal end of the pin 522 opposite the distal end. The second torque shoulder 526 includes a shoulder surface 535, or load bearing surface, that can engage (e.g., contact) the shoulder surface 515 of the first torque shoulder 516 of the first tubular member 510. The shoulder surface 535 of the second torque shoulder 526 is also referred to as the second torque shoulder surface. The second torque shoulder 526 forms a ring shape around the cylindrical diameter of the second pin 522 at the distal end of the second tubular member 520. The ring shape of the second torque shoulder 526 can be continuous around an entire circumference of the ring shape. However, in some instances, the ring shape can be non-continuous, or segmented. As described earlier, the surface profile of the torque shoulder 526 can vary. For example, the torque shoulder 526 can have a flat surface profile, a tapered conical surface profile, or a combination of both, with respect to a radial of the tubular member 520.

The shoulder surface 515 of the first torque shoulder 516, the shoulder surface 535 of the second torque shoulder 526, or both the shoulder surfaces 515, 535 of the first torque shoulder 516 and the second torque shoulder 526 can have a surface roughness greater than the minimum threshold roughness, described earlier.

To form the example connection 500, the first pin 512 is inserted into the first box 504a to engage the corresponding threading, and the second pin 522 is inserted into the second box 504b to engage the corresponding threading, and the first torque shoulder 516 and the second torque shoulder 526 engage (i.e., contact) each other. As the pins 512 and 522 are rotated relative to the coupling box connector 502 toward a complete engagement, the respective torque shoulder surfaces of the pins 512 and 522 approach each other. Upon a complete rotational installment of the first pin 512 with the first box 504a and the second pin 522 with the second box 504b, the shoulder surface 515 of the first torque shoulder 516 engages with (e.g., contacts) the shoulder surface 535 of the second torque shoulder 526. FIG. 12B shows this contacting engagement. The coupling of the first tubular member 510 and the second tubular member 520 with the coupling box connector 502 can be referred to in the art as making-up the tubular goods connection 500. When the example tubular goods connection 500 is made-up, the first internal wedge thread 506a engages the first external wedge thread 514 via an interference fit of the mating wedge threads, the second internal wedge thread 506b engages the second external wedge thread 524 via an interference fit of the mating wedge threads, and the first torque shoulder 516 engages (i.e., contacts) the second torque shoulder 526 via an interference fit of the contacting shoulder surfaces 515, 535.

Similar to the example connections 100, 100′, and 100″, in some implementations, the coupling box connector 502 can include a positive-stop torque shoulder that engages one or both of the shoulder surfaces of the first tubular member 510 and/or second tubular member 520. For example, the coupling box connector 502 can include a radially inward flange between the first box 504a and the second box 504b that can abut and engage the shoulder surfaces 515, 535 of the first torque shoulder 516 and the second torque shoulder 526 (instead of the first torque shoulder 516 directly abutting and engaging the second torque shoulder 526).

In FIGS. 12A and 12B the example connection 500 is shown in made-up state. As an alternative, upon initial make-up, the torque shoulder surfaces are at an axial distance from each other. The torque shoulder surfaces may then during use, i.e. in the well, engage in case torque applied to the connection exceeds the torque resistance of the wedge thread. The torque shoulder surfaces thus serve as a backup for over-torque conditions during use. Examples of connections with wedge threads wherein upon make-up torque shoulder surfaces are at an axial distance from each other are illustrated in U.S. Patent Publication No. US2017/0314596 to Harvey et al., incorporated herein by reference in its entirety.

FIGS. 12A and 12B show the example connection 500 as a wedge thread connection; however, the type of tubular connection can be different. The thread profile can be a buttress profile such as in the example connections 100, 100′ and 100″ described herein above. Furthermore, the thread profile of the connection can be other thread profiles that can be used in combination with a torque shoulder.

A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. In particular, the thread profile of the connection can be other thread profiles that can be used in combination with a torque shoulder. Furthermore, the torque shoulder surfaces can be at another location than at a longitudinal end of a pin or a box. The torque shoulder surfaces can be located at a location between the longitudinal ends of a pin or a box, for instance at a location between two axially separated threaded zones of a pin or a box. Examples of connections with torque shoulder surfaces between two axially separated threaded zones of a pin or a box are illustrated in U.S. Patent Publication No. US2010/0181763 to Mallis et al., incorporated herein by reference in its entirety.

TORQUE SHOULDER FOR TUBULAR GOODS CONNECTION

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