Coupling for threaded joints

Abstract

A coupling for a threaded joint is provided. The coupling includes a tubular body having first and second ends. Each end has a box having an inner surface thereon which female threads are formed for engagement with a pin of the tubular component. The coupling further includes a first female electrical contact insulated from the tubular body on the inner surface of the first end; a second female electrical contact insulated from the tubular body on the inner surface of the second end; and a longitudinal conductor communicating with the first and second female electrical contacts and insulated from the tubular body. The tubular body has a conductor hole formed therein which a longitudinally extending hole is formed, through which the longitudinal conductor extends.

Description

Background Art

[0001] Background During operations inside a wellbore, such as during drilling, it may be desirable to measure and communicate the state of the wellbore. This may be, for example, measurements of pressure and / or temperature of the in-well state.

[0002] Typically, a casing string is inserted into the wellbore, which is a tubular structure inside the wellbore to support the hole. Inside this, a drill string is provided. The casing is exposed to the state outside the wellbore, which, due to a much harsher environment, must be much more robust than the drill string. The casing is exposed to the pressure of a very large possible reservoir, while the drill string is only exposed to the hydrostatic pressure inside the casing. Also, a tubing string may exist between the casing string and the drill string.

[0003] The drill string can typically be retrieved after a few days, during which repairs can be made. This does not apply to the casing string or tubing string remaining in the wellbore. The sealing requirements for the drill string are also much looser and may not require any metal-to-metal seals, for example. The drill string is typically provided with an outer diameter of 2.375 inches to 6.625 inches.

[0004] The use of wired sensors has generally not been successful because the harsh in-well environment can easily damage the wires extending downward into the wellbore. For example, perforating explosives are frequently used during in-well operations, which will damage the wiring extending to the in-well sensors.

[0005] Wireless sensors are also used, which are battery-powered to avoid the need for wiring extending into the wellbore. In addition to the depth of the wellbore and the problem of communication due to an environment generally not suitable for wireless transmission, battery depletion will naturally occur. As a result, while the wireless sensor is retrieved for battery replacement / charging, the in-well operation must be stopped and the tool removed. This halts the wellbore operation.

[0006] The use of optical fibers has also been considered. However, this requires a separate cable that is clamped to the string. If there are multiple cables connected together along the string, they also need to be carefully aligned with each other to enable transmission along the string. These individual cables may be clamped to the outer surface of the string and connected to each other on this outer surface.

[0007] Patent Document 1 discloses a device for acquiring and communicating data between strings of an oil or gas well. This system requires supplying wires along the string to various battery-powered sensors. Alignment of threaded components is necessary to supply these wires, as rotation could damage the device. Furthermore, the system requires an electromagnetic field to power the batteries. This means that all components of the string must be non-magnetic.

[0008] Patent Document 2 discloses an electrical conduction system between sections of a drill pipe string. A connector is provided at the end of the male section for engaging with a connector provided on the female section. Since this connection is provided on the drill string, it is not exposed to the harsh conditions of the casing string. Furthermore, since the outer surface rotates within the casing and is exposed to significant external forces, the wire passes through the inside of the drill string and is considered unsuitable for wiring.

[0009] Patent documents 3 and 4 disclose systems for underground power and data transfer. Multiple power transfer spring structures are provided, which contact the corresponding paths when the screw coupling is assembled. Since each spring structure represents a different path, careful alignment of the spring structures and each path is required. This means that the two sets of contacts are the same size and, to ensure alignment, the coupling is positioned directly adjacent to the shoulder of the screw coupling. If any misalignment exists in the axial direction, power and data transfer will not function.

[0010] Patent Document 5 discloses a drill pipe comprising a pin-end connector, a box-end connector, a first communication connector, and a second communication connector. The pin-end connector includes a first region for forming a threaded joint to connect sections of the drill pipe together, the first region comprising at least one thread starting from one end of the first region and ending at the other end of the first region. The box-end connector receives the pin-end connector, and the box-end connector includes a second region that mates with the first region to form a threaded joint. The first communication connector is coupled to the pin-end connector and located within the first region; the second communication connector is coupled to the box-end connector and located within the second region to form a communication connection with the first communication connector. This is directed towards the drill string, and as a result the string rotates at high speed, any external wiring cannot be placed externally because any external wiring would be damaged during use. Furthermore, since the drill string is a component of thicker walls, wiring can be accommodated within the central portion of each wall.

[0011] Patent document 6 discloses an arrangement of electrical connectors positioned at the joints of drill string pipe sections connected together to form a remote measuring drill string. The electrical connectors are positioned at the pipe joints and connect the insulating segments of the electrical connectors positioned in the drill string pipe sections.

[0012] Patent Document 7 discloses a wired drill pipe segment for a drill string positioned in a well. The pipe segment includes a box end and a pin end. Communication couplers are positioned at each of the box and pin ends. Conductors connect the communication couplers and extend through at least a portion of the hole in the pipe. Preferably, means for protecting the conductors are provided in the form of expandable sleeves positioned inside the pipe, which are plastically expandable and bonded to the inner wall of the pipe. Alternatively, a wired pipe segment having multiple induction windings and conductors is disclosed. A wired pipe segment is disclosed that includes a communication coupler containing a transformer held in the slot by a filler. This is a pipe segment and not a coupling. As a result, it has different male / female threads at both ends. Furthermore, given the size of the pipe segment, there is no through hole extending between the ends for the conductor to pass along its entire length.

[0013] Patent Document 8 discloses a drill pipe including a pin-end connector, a box-end connector, a first communication connector having a plurality of first communication contacts, and a second communication connector having a plurality of second communication contacts. The pin-end connector is received by the box-end connector to connect the sections of the drill pipe together. When the drill pipe sections are connected by the pin-end and box-end connectors, a plurality of isolated communication connections are formed between the first and second communication contacts. Again, this is a section of pipe, not a coupling.

[0014] Patent document 9 discloses a drilling system comprising a drill string including a drill bit, a bottom-of-hole assembly connected to the drill bit, and a plurality of interconnected tubular members connected to the bottom-of-hole assembly. The first tubular member is positioned in an annular recess at the first end. The drilling system includes a first annular inductive coupling element, a second annular inductive coupling element disposed within a second terminal annular recess, and a communication link having a cable connecting the first annular inductive coupling element to the second annular inductive coupling element. In addition, the drilling system includes a first signal level determination unit disposed within the drill string and configured to determine the level of a first signal communicated from the second inductive coupling element. Furthermore, the drilling system includes an axial load determination unit configured to determine the axial load in the first signal level determination unit based on the level of the first signal.

[0015] Therefore, an improved system is needed, particularly for communicating sensed in-well conditions, especially for casing strings or tubing strings. [Prior art documents] [Patent Documents]

[0016] [Patent Document 1] U.S. Specification No. 2021 / 0310350 A1 [Patent Document 2] U.S. Specification No. 2004 / 0242044 A1 [Patent Document 3] International Publication No. 2022 / 197745 A1 Pamphlet [Patent Document 4] International Publication No. 2022 / 094144 A1 Pamphlet [Patent Document 5] U.S. Patent No. 2010 / 264650 A1 [Patent Document 6] U.S. Specification No. 3879097A [Patent Document 7] British Patent No. 2433080 A Specification [Patent Document 8] U.S. Patent No. 2009 / 166087 A1 [Patent Document 9] US Patent No. 9157313 B2 [Overview of the project]

[0017] A coupling for a screw joint is provided. The coupling is a tubular body having first and second ends, each end having a box with an inner surface on which an internal thread for engagement with a pin of a tubular component is formed; a first female electrical contact on the inner surface of the first end, insulated from the tubular body; a second female electrical contact on the inner surface of the second end, insulated from the tubular body; and a longitudinal conductor communicating with the first and second female electrical contacts and insulated from the tubular body, the tubular body having a conductor hole formed therein that includes a longitudinally extending hole through which the longitudinal conductor extends. In certain cases, the tubular body has a longitudinally extending hole formed therein.

[0018] With this coupling, effective electrical connectivity can be effectively achieved across the coupling, particularly with respect to a casing string.

[0019] The first female electrical contact may extend circumferentially around the inner surface; and / or the second female electrical contact may extend circumferentially around the inner surface. This can help ensure an effective electrical connection regardless of the rotational alignment. This may relate to a portion of the inner surface or the entire circumference of the inner surface.

[0020] The conductor may be formed from a first wire and a second wire joined to each other at a location within the longitudinally extending hole. Such an arrangement allows the coupling to be formed without excess wire, with each wire inserted at the opposite end of the hole.

[0021] The first wire may be joined to the second wire using a connector within the longitudinally extending hole. The connector within the hole is an effective way to join the two wires. The connector may extend across the entire hole or a portion of the hole.

[0022] The connector may include a solder sleeve. The solder sleeve is external to the coupling By applying local heat, it can be melted to join the first and second wires together for electrical connection.

[0023] The connector may include heat shrink tubing; i.e., tubing that is activated by heat to reduce its inner diameter. This can hold the wires in an electrically connected state and can be easily activated externally by applying heat to the coupling. Each female electrical contact may include a deformable element that is deflected towards the inside of the box. Such contacts can help ensure a reliable electrical connection in an assembled configuration.

[0024] Each deformable element is a circumferentially extending coil spring. This is an effective way to implement a deformable element, especially in situations where components are subject to radial interference.

[0025] The coupling includes a first plurality of female electrical contacts on the inner surface of the first end, each insulated from the tubular body, having a second circumferential length, and spaced apart from each other by a second circumferential gap; and It may further include a second plurality of female electrical contacts on the inner surface of the end of the second end, each insulated from the tubular body, having a third circumferential length, and spaced apart from each other by a third circumferential gap. This allows multiple electrical signals to be transmitted along the screw joint while still accommodating rotational misalignment of the screw joint.

[0026] Each female electrical contact may be insulated from the tubular body by an elastomeric seal, with the female electrical contact and conductor embedded within the seal and partially exposed to form the female electrical contact. The elastomeric seal is an effective way to insulate the female electrical components while also forming both the seal and the electrical connection.

[0027] The tubular body may include a first radially extending hole at the first end that extends longitudinally from a first female electrical contact, and a second radially extending hole at the second end that extends longitudinally from a second female electrical contact. This allows for the formation of a coupling using the individual holes to create a concave longitudinal hole and a passage leading thereto.

[0028] The longitudinally extending hole may have a blind hole with an opening at the first end of the tubular body. This means that the longitudinally extending hole can be formed from one end of the coupling in a single machining step. The blind hole can be formed by either not machining the entire length of the coupling or by closing the blind hole of the through hole.

[0029] The opening of a longitudinally extending hole may be closed using a plug. This seals the hole from external access and prevents the perforating fluid and / or debris from entering the hole.

[0030] A longitudinal conductor may extend from the first female electrical contact to the second female electrical contact only along the conductor hole. That is, the conductor does not extend on the inner or outer surface, and the hole needs to extend effectively along most, if not the entire length, of the conductor.

[0031] Longitudinal conductors may be spaced apart from the outer and / or inner surfaces of the coupling along their entire length. This helps protect the conductors by ensuring that they do not extend beyond their length to the outer surface.

[0032] The axial length of the coupling may be 20 inches or less, preferably 12 inches or less. Such a length is suitable for connecting the tubular components discussed herein.

[0033] The axial length of the coupling may be 5 inches or more, preferably 7 inches or more. Such a length is suitable for connecting the tubular components discussed herein.

[0034] A threaded coupling is provided. The threaded coupling comprises the coupling described above and herein; a first tubular component and a further tubular component, each tubular component comprising: a pin having an outer surface thereon which a male thread is formed in a first end region, each male thread being arranged to engage with a female thread of the coupling in an assembled configuration; a second end region on the opposite side; a male electrical contact insulated from the tubular component on the outer surface of the first end region of the tubular component; and a first conductor extending along the tubular component, communicating with the male electrical contact and insulated from the tubular component, wherein the male and female electrical contacts are arranged to be in contact with each other in an assembled configuration. The further tubular component may be called a second tubular component.

[0035] This threaded joint provides effective electrical connectivity along threaded joints, particularly casing strings.

[0036] Each male electrical contact may extend circumferentially around the outer surface. This can help ensure a valid electrical connection regardless of rotational alignment. This may be a portion of the inner surface or the entire circumference of the inner surface.

[0037] Each tubular component may further include a plurality of male electrical contacts on the outer surface of the end region of the first tubular component, each insulated from the tubular component, having a first circumferential length and spaced apart from each other by a first circumferential gap, where the first circumferential length is smaller than the second and third circumferential gaps; the second and third circumferential lengths are smaller than the first circumferential gap. This allows multiple electrical signals to be transmitted along the threaded joint while still accommodating the rotational displacement of the threaded joint.

[0038] The first tubular component may be the first casing tubular component, and the second tubular component may be the second casing tubular component.

[0039] A method for manufacturing a coupling for threaded joints is provided. The method includes: forming a tubular body having first and second ends, each end having a box having an inner surface thereon which female threads are formed for engaging with a pin of a tubular component; machining a longitudinally extending hole through the tubular body; and inserting an insulating conductor into the longitudinally extending hole to communicate with a first female electrical contact and a second female electrical contact, wherein the first female electrical contact is on the inner surface of the first end and insulated from the tubular body, and the second female electrical contact is on the inner surface of the second end and insulated from the tubular body. This method is particularly suitable for manufacturing couplings, especially holes that are offset from the inner and outer surfaces.

[0040] The first female electrical contact may extend circumferentially around the inner surface; and / or the second female electrical contact may extend circumferentially around the inner surface. This can help ensure a valid electrical connection regardless of rotational alignment. This may be a portion of the inner surface or the entire circumference of the inner surface.

[0041] The insulating conductor may include a first wire and a second wire, and the insulating conductor is oriented in the longitudinal direction. Insertion into extending holes includes inserting a first wire into a hole extending longitudinally from a first end of a tubular body; and inserting a second wire into a hole extending longitudinally from a second end of a tubular body so that the first and second wires are electrically connected. Such an arrangement allows for the formation of a coupling without excess wire, with each wire inserted at the opposite end of the hole.

[0042] The method may further include: 1) positioning a connector in a longitudinally extending hole, wherein the step of inserting a first wire includes inserting the first wire into the connector, and the step of inserting a second wire includes inserting the second wire into the connector; and 2) heating a tubular body to activate the connector and coupling the first wire to the second wire. Activating the connector may include melting a solder sleeve and / or shrinking heat-shrinkable tubing. This allows the two wires to be coupled to each other by applying heat to the outside of the coupling. The connector may span the entire hole or a portion of the hole. The connector may include a solder sleeve. The solder sleeve can be melted by applying external heat to the coupling, thereby joining the first and second wires together and creating an electrical connection.

[0043] The connector may include heat-shrink tubing, i.e., tubing that is activated by heat and reduces its inner diameter. This holds the wires in an electrically connected state and can be easily activated externally by applying heat to the coupling.

[0044] The first female electrical contact may be fixed to the first wire before the first wire is inserted. For example, the first female electrical contact may be integrally molded to the end of the first wire. The electrical contacts may be inserted through a hole, and thus these fixed electrical contacts can be used by connecting the wires within the hole.

[0045] The second female electrical contact may be fixed to the second wire before the second wire is inserted. For example, the second female electrical contact may be integrally molded to the end of the second wire. The electrical contacts may be inserted through a hole, and thus these fixed electrical contacts can be used by connecting the wires within the hole.

[0046] The method may further include the steps of machining a first radially extending hole at a first end to a longitudinally extending hole; and machining a second radially extending hole at a second end to a longitudinally extending hole, wherein an insulating conductor is inserted through the first radially extending hole and the second radially extending hole. This allows a coupling to be formed using the individual holes, creating a concave longitudinal hole and a passage thereto.

[0047] A longitudinally extending hole may have blind holes. This means that a longitudinally extending hole can be formed from one end of the coupling in a single machining step. Blind holes can be formed either by not machining the entire length of the coupling or by closing the blind holes of through holes.

[0048] The method may further include a step of closing the opening of the longitudinally extending hole. This can seal the hole from external access and prevent perforating fluid and / or debris from entering the hole.

[0049] Connectors may be positioned before their ends are closed. Connector positioning takes place before the coupling is inserted into the well. Connectors may be inserted linearly through the longitudinal hole before their ends are closed and sealed.

[0050] A string for a well is provided. The string includes a plurality of screw fittings as described above and herein, which are screw-engaged to form the string such that a first conductor and a longitudinal conductor collectively form a conductive path; and one or more sensors arranged along the string and communicating with the conductive path.

[0051] This string connection provides effective electrical connectivity along threaded joints, particularly for casing strings.

[0052] A conductive path may transmit power to one or more sensors and transmit signals from one or more sensors. This allows a single conductive path to transmit both power and signal information.

[0053] One or more sensors may include one or more of the following: temperature sensors; pressure sensors; accelerometers; magnetometers; ultrasonic sensors; flow sensors; and / or acoustic sensors. Such sensors detect the parameters of interest of the string.

[0054] The strings may be casing strings or tubing strings, and each tubular component may be a casing or a tubular component. Simple explanation This description is based on the attached drawings, which are for illustrative purposes only. [Brief explanation of the drawing]

[0055] [Figure 1] Figure 1 shows a close-up side cross-sectional view of a threaded joint. [Figure 2] Figure 2 shows a side view of the first tubular component for the threaded joint. [Figure 3] Figure 3 shows a perspective cross-sectional view of the second tubular component for the threaded joint. [Figure 2A] Figure 2A shows a perspective view of a further first tubular component for a threaded joint. [Figure 2B] Figure 2B shows a front cross-sectional view of a further first tubular component of Figure 2A. [Figure 4] Figure 4 shows a side cross-sectional view of a further threaded joint. [Figure 5] Figure 5 shows a close side cross-sectional view of the coupling used in the further threaded joint in Figure 4; [Figure 6] Figure 6 shows a perspective cross-sectional view of the coupling in Figure 5. [Figure 7] Figure 7 shows a close-up perspective cross-sectional view of the connector used in the coupling shown in Figure 6. [Figure 8] Figure 8 shows a side cross-sectional view of the connector shown in Figure 7. [Figure 9A] Figure 9A shows a cross-sectional view of an electrical connection that may be used with the threaded fittings shown in Figure 1 or Figure 4. [Figure 9B] Figure 9B shows a cross-sectional view of Figure 9A at a rotationally shifted position. [Modes for carrying out the invention]

[0056] Figure 1 shows an example of a threaded joint 100 comprising a first tubular component 200 shown in Figure 2 and a second tubular component 300 shown in Figure 3. This threaded joint 100, including the first tubular component 200 and the second tubular component 300, may be part of a casing string or tubing string. That is, a casing string suitable for receiving a drill string, as described above, or a tubing string positioned between a casing string and a drill string, again as described above. It should be understood that any reference to “casing string” in this disclosure is equally applicable to a tubing string. Casing strings or tubing strings may be used in many different operations, including but not limited to production and injection.

[0057] The casing string, particularly its inner diameter, will have a larger diameter than the drill string to be used with it. The outer diameter of the casing string can range from 4 inches to 24 inches.

[0058] Furthermore, casing strings may have different types of threaded fittings compared to drill strings. In casing strings, these may be one-piece and have thicker upset sections, making them more robust. Drill strings may have greater wall thickness than casing strings because they generally need to be more durable. Casing strings will typically use a different grade of steel than drill strings.

[0059] Generally, the threaded joint 100 is formed from a first tubular component 200 and a second tubular component 300. The first tubular component 200 and the second tubular component 300 can be arranged in an assembly configuration as shown in Figure 1.

[0060] A first tubular component 200, particularly the first terminal region of the first tubular component 200, is shown in Figure 2. The first tubular component 200 may include a second terminal region at the opposite end. The first and second terminal regions may be substantially similar to, identical to, or different from each other. In the first terminal region, the first tubular component 200 includes a pin. The pin has an outer surface on which a male thread 21 is formed. The first tubular component 200 may generally be cylindrical.

[0061] A second tubular component 300, particularly the first end region of the second tubular component 300, is shown in Figure 3. The first tubular component 300 may include a second end region at its opposite end. The first and second end regions may be substantially similar to, identical to, or different from each other. In the second end region, the second tubular component 300 includes a box. The box has an inner surface on which a female thread 31 is formed. The first tubular component 200 may generally be cylindrical. The female thread 31 of the box may generally correspond to the male thread 21 of the pin. In the assembly configuration, the male thread 21 of the pin and the female thread 31 of the box may engage with each other. That is, the male thread 21 of the pin may be threaded into the female thread 31 of the box to form the assembly configuration.

[0062] The male thread 21 and female thread 31 may be any suitable type of thread for forming the threaded joint 100. In certain examples, the male thread 21 and female thread 31 may be or include threads with variable thread width, also known as wedge threads or self-locking threads; that is, threads whose axial width increases along their length. The male thread 21 and / or female thread 31 may include a division of threads with variable thread width and a division of threads with constant thread width.

[0063] The first tubular component 200 and the second tubular component 300 may together form one or more seals in this assembly configuration.

[0064] The male electrical contact 24 extends circumferentially around the first tubular component 200, particularly around the outer surface of the pin. The male electrical contact 24 may extend only slightly circumferentially (as shown particularly in Figures 2A and 2B). In other examples, the male electrical contact 24 may extend around the entire circumference or a portion of the circumference of the first tubular component 200. The male electrical contact 24 may form a cylindrical shape together with the outer surface of the male tubular component 200. This can be a cylindrical shape that is substantially continuous with the outer surface of the male tubular component 200.

[0065] The male electrical contact 24 may be axially offset from the male screw 21. For example, the male screw 21 may be located between the male electrical contact 24 and the end of the first tubular component 200, particularly the pin. In other words, the end region of the first tubular component 200 (e.g., the illustrated first end region) may include, in order, the end, the male screw 21, and then the male electrical contact 24. This configuration may be located at one end of the first tubular component 200, or at both ends of the first tubular component 200 (i.e., the first end region and the second end region). These elements may be directly adjacent to each other, or there may be a space between them. The end in this sense is the end closest to the male electrical contact 24, that is, not the end on the opposite end of the first tubular component 200 which would not be in the same end region.

[0066] The reference herein to the axial direction may be understood as a centerline passing along the length of the first tubular component 200 or the second tubular component 300. Each tubular component 200, 300 may generally be a hollow cylinder defining the axial, radial, and hoop directions. The axial direction is the line passing through the center of each base of the cylinder.

[0067] The male electrical contact 24 is insulated from the first tubular component 200. That is, the male electrical contact 24 may be electrically insulated from and / or isolated from the first tubular component 200. For example, the male electrical contact 24 may be a conductive ring extending circumferentially around the first tubular component 200. An insulator, such as an elastomer ring, may be provided between the male electrical contact 24 and the first tubular component 200 to electrically insulate the electrical contact 24 from the first tubular component 200.

[0068] The first conductor 22 extends along the first tubular component 200, for example, in the axial direction. The first conductor 22 is electrically connected to the male electrical contact 24. The first conductor 22 may extend precisely in the axial direction, as shown in Figure 2. However, in further examples, the first conductor 22 may deviate from this purely axial path. For example, the first conductor 22 may also have circumferential and / or radial deviations from the purely axial path.

[0069] The first conductor 22 is electrically insulated from the first tubular component 200. For example, the first conductor 22 may be in the form of a wire having a conductive core covered with a non-conductive covering. Alternatively or additionally, an insulator may be provided between the first conductor 22 and the first tubular component 200.

[0070] The female electrical contact 34 extends circumferentially around the inner surface of the second tubular component 300, particularly the box. In certain examples, the female electrical contact 34 may extend around the entire circumference or a portion of the circumference of the second tubular component 300. The female electrical contact 34 may form a cylindrical shape within the inner surface of the female tubular component 300. This may be a substantially continuous cylindrical shape within the inner surface of the female tubular component 300.

[0071] The female electrical contact 34 may be axially offset from the female thread 31. For example, the female electrical contact 34 may be located between the female thread 31 and the second tubular component 300, particularly the end of the box. In other words, the end region of the second tubular component 300 (e.g., the illustrated first end region) may include, in order, the end, the female electrical contact 34, and then the female thread 31. This configuration may be located at one end of the second tubular component 300 or at both ends of the second tubular component 300 (i.e., the first end region and the second end region). These elements may be directly adjacent to each other, or there may be a space between them. The end in this sense is the end closest to the female electrical contact 34, that is, not the end on the opposite end of the second tubular component 300 which would not be in the same end region.

[0072] The female electrical contact 34 is insulated from the second tubular component 300. For example, female electrical contact Point 34 may be at least partially insulated from the second tubular component 300 by the elastomer seal 35. For example, the female electrical contact 34 may be embedded within the elastomer seal 35 or otherwise permanently fixed and protruding from there. Alternatively, a deformable element, such as a coil spring, may be held between the elastomer seal 35 and a further component, such as an anti-extension ring. These anti-extension rings may be non-conductive and may help insulate the female electrical contact 34 from the second tubular component 300.

[0073] The elastomer seal 35 may contact the first tubular component 200, particularly the pin, to form a seal with the first tubular component 200. Again, this may be part of an interference seal or an inner seal. Further support rings, such as a PEEK ring, may be present. A split locking ring may be provided to hold the female electrical contact 34 and any further elements within this area in place.

[0074] The second conductor 32 extends along the second tubular component 300, for example, in the axial direction. The second conductor 32 is electrically in communication with the female electrical contact 34. The second conductor 32 may extend precisely in the axial direction, as shown in Figure 3. However, in further examples, the second conductor 32 may deviate from this purely axial path. For example, the second conductor 32 may also have circumferential and / or radial deviations from the purely axial path.

[0075] The second conductor 32 is electrically insulated from the second tubular component 300. For example, the second conductor 32 may be in the form of a wire having a conductive core covered with a non-conductive covering. Alternatively or additionally, an insulator may be provided between the second conductor 32 and the second tubular component 300.

[0076] In the assembly configuration shown in Figure 1, the male screw 21 and the female screw 31 engage, and the male electrical contact 24 contacts the female electrical contact 34. That is, the male electrical contact 24 and the female electrical contact 34 engage with each other to form an electrical connection. This is shown in Figure 1. More specifically, this may be the male contact surface of the male electrical contact 24 contacting the female contact surface of the female electrical contact 34.

[0077] As a result, a conductive path is defined from the first conductor 22 through the male electrical contact 24 to the female electrical contact 34, and then to the second conductor 32. That is, the assembly of the first tubular component 200 and the second tubular component 300 also forms a conductive path that crosses both the first tubular component 200 and the second tubular component 300.

[0078] The first tubular component 200 may have a described pin and associated male electrical contact 24 at one end region and a box similar to that generally described in relation to the second tubular component 300 at the opposite end region. Similarly, the second tubular component 300 may have a described box and associated female electrical contact 34 at one end region and a pin similar to that generally described in relation to the first tubular component 200 at the opposite end region. Such tubular components 200, 300 may be referred to as integral fittings.

[0079] Alternatively, a first tubular component 200, which may have the described pin and associated male electrical contact 24 at one end, may have an additional pin and associated male electrical contact 24 at the opposite end. Similarly, a second tubular component 300 may have the described box and associated female electrical contact 34 at one end, and an additional box and associated female electrical contact 34 at the opposite end.

[0080] In this sense, the string of threaded joint 100 can form a continuous electrical connection that extends along the entire length of the string.

[0081] Sensors placed within the tunnel may be connected to this continuous electrical connection, thereby establishing electrical communication with the sensors. These sensors may include temperature sensors, pressure sensors, accelerometers, magnetometers, ultrasonic sensors, flow sensors, acoustic sensors, or any other type of sensor.

[0082] In certain examples, the first tubular component 200 may include grooves or recesses formed on its outer surface. These can be formed by either machining or milling the outer surface. The grooves may be curved in cross-section; that is, the grooves may not contain sharp corners that could act as stress concentration areas. In certain examples, the grooves may have a U-shaped cross-section. For example, the grooves may have a radius of curvature of less than 5 millimeters. In certain examples, the radius of curvature of the grooves may be between 1 and 2 millimeters.

[0083] The first conductor 22 may then extend into this groove. This may prevent the first conductor 22 from extending beyond the outer circumference of the outer surface. That is, the first tubular component 200 does not have a larger outer diameter as a result of the introduction of the first conductor 22.

[0084] To further protect the first conductor 2 from external influences of the underground environment, a sealing cover 23 (shown in Figures 2A and 2B) may be provided. This sealing cover 23 may be coupled to the outer surface of the first tubular component 200 to cover the first conductor 22. For example, the first conductor 22 may be located in a groove over which the sealing cover 23 is provided.

[0085] As described above, in the assembly configuration, the first tubular component 200 and the second tubular component 300 may be sealed to each other. This may be done via one or more sealing surfaces. For example, an inner seal and / or an outer seal may be present. A sealing surface 29 may be provided on the first tubular component 200 to form an interference seal with the corresponding sealing surface 39 of the second tubular component 300.

[0086] In the terminal region, the sealing surface 29 may be positioned such that the male thread 21 is located between the sealing surface 29 and the first tubular component 200, particularly the end of the pin.

[0087] The male electrical contact 24 may be axially offset from the male screw 21. For example, the male electrical contact 24 may be located between the sealing surface 29 and the male screw 21. In other words, the terminal region of the first tubular component 200 (e.g., the illustrated first terminal region) may include, in order, the terminal, the male screw 21, the male electrical contact 24, and then the sealing surface 29. This configuration may be located at one end of the first tubular component 200 or at both ends of the first tubular component 200 (i.e., the first terminal region and the second terminal region). These elements may be directly adjacent to each other, or there may be a space between them. The terminal in this sense is the terminal closest to the male electrical contact 24, that is, not the terminal on the opposite end of the first tubular component 200 which would not be in the same terminal region.

[0088] To avoid disturbance in the sealing surface 29, the groove in which the first conductor 22 is located may communicate with a hole 28 extending beneath the sealing surface 29. This is best illustrated in Figure 1. In other words, the groove may be a surface groove extending to the vicinity of the sealing surface 29. The groove may then extend to the diameter of the first tubular component 200 to form a hole 28, which generally functions as a tunnel beneath the sealing surface 29. Thus, the sealing surface 29 may be continuous (i.e., uninterrupted) around the entire circumference of the first tubular component 200. The corresponding sealing surface 39 may be continuous (i.e., uninterrupted) around the entire circumference of the second tubular component 300, separately or additionally. (It may not be interrupted.)

[0089] As shown in Figure 1, the hole 28 may include a first and second corner-forming section that converges at its apex, or any other suitable shape. This shape may be formed by drilling one or more holes within the first tubular component 200.

[0090] The corresponding sealing surface 39 of the second tubular component 300 may be positioned in the terminal region such that the corresponding sealing surface 39 is located between the female thread 31 and the end of the second tubular component 300, particularly the end of the box.

[0091] The female electrical contact 34 may be axially offset from the female thread 31. For example, the female electrical contact 34 may be located between the corresponding sealing surface 39 and the female thread 31. In other words, the end region of the second tubular component 300 (e.g., the illustrated first end region) may, in order, include the end, the corresponding sealing surface 39, the female electrical contact 34, and then the female thread 31. This configuration may be located at one end of the second tubular component 300 or at both ends of the second tubular component 300 (i.e., the first end region and the second end region). These elements may be directly adjacent to each other, or there may be a space between them. The end in this sense is the end closest to the female electrical contact 34, that is, not the end on the opposite end of the second tubular component 300 which would not be in the same end region.

[0092] The sealing surface 29 and the corresponding sealing surface 39 may form at least part of an interference seal between the first tubular component 200 and the second tubular component 300. Such a seal may also be referred to as an outer seal.

[0093] In some cases, the male electrical contact 24 may be used for sealing. The male electrical contact 24 may form an interference seal, or part of a separate interference seal or inner seal. That is, the contact between the male electrical contact 24 and the female electrical contact 34 may help to seal the threaded joint 100.

[0094] In certain examples, the female electrical contact 34 is insulated at least partially from the second tubular component 300 by an elastomer seal 35. This elastomer seal 35 may come into contact with the first tubular component 200, particularly with the pin, thereby forming a seal with the first tubular component 200. Again, this may be part of an interference seal or an internal seal.

[0095] Further or alternative seals, such as an internal seal, may be provided for the threaded joint 100. The first tubular component 200, in particular the pin, may include an annular sealing surface. This annular sealing surface may be sealed by interference with the annular sealing surface of a complementary second tubular component 300, in particular the box. The annular sealing surface of the first tubular component 200 may be located in a first end region between the male thread 21 and the end of the first tubular component 200, in particular the pin. In other words, the end region of the first tubular component 200 (e.g., the illustrated first end region) may, in order, include the end, the annular sealing surface of the first tubular component 200, the male thread 21, the male electrical contact 24, and (optionally) then the sealing surface 29. This configuration may be located at one end of the first tubular component 200 or at both ends of the first tubular component 200 (i.e., the first end region and the second end region). These elements may be directly adjacent to each other, or there may be space between them. In this sense, the terminus is the male electrical contact 24, which is the closest terminus to the first tubular component 200, that is, not the terminus on the opposite end of the first tubular component 200, which would not be in the same terminus region.

[0096] In the assembly configuration, there may be some variation in the range in which the male thread 21 and the female thread 31 engage. That is, by applying further torque, the male thread 21 can engage the female thread 31. It may be possible to screw them in further. The torque value may be specified for the assembly configuration, which represents the amount of torque that needs to be applied to the components to achieve this assembly configuration. The range of engagement of the male thread 21 and the female thread 31 affects the relative axial position of the male electrical contact 24 and the female electrical contact 34.

[0097] The threaded joint 100 may be a threaded joint 100 without a shoulder. Such a threaded joint 100 without a shoulder may, in particular, use a thread with a variable thread width, also known as a wedge thread or a self-locking thread. Such a thread may constitute at least a portion of the male thread 21 and / or female thread 31. As described above, a thread with a variable thread width may control the relative assembly position instead of a shoulder. Alternatively or additionally, if the second tubular component 300 has a box at each end, the end of the first tubular component 200 inserted into the box may, in some cases, abut with the end of a further tubular component 200 inserted into another box. Such abutment between the end of the first tubular component 200 and the end of the further tubular component 200, also known as pin-to-pin contact, may control the relative assembly position instead of a shoulder.

[0098] Such shoulderless threaded joints with pin-to-pin contact may be used with threads of varying widths, or alternatively, with threads of fixed widths, as described above. In such shoulderless threaded joints with pin-to-pin contact, the pin-to-pin contact may control the relative assembly position instead of the shoulder. This is particularly important because such shoulderless threaded joint 100 may have an uncertain assembly configuration. That is, when in the assembly configuration, there may be axial variations in the positions of the first tubular component 200 and the second tubular component 300.

[0099] There may be indeterminate assembly configurations where the assembly position is determined based on the interference between the apex and root of each screw. Similarly, there may be indeterminate assembly configurations based on the height and taper angle of each screw. In each case, the screw reaches a point where it cannot advance any further (for example, when a certain torque is applied). However, this is not a precise axial alignment.

[0100] In detail, the first end region 200 of the first tubular component and / or the first end region 300 of the second tubular component (i.e., the end regions where the respective male electrical contacts 24 and female electrical contacts 34 are located) may not have shoulders.

[0101] The male electrical contact 24 may have an axial width to ensure that electrical contact with the female electrical contact 34 can be maintained despite this variation in axial position. Alternatively, of course, this width may be provided for the female electrical contact 34 in the same manner. In detail, the width may be greater than 3 millimeters. Alternatively, there may be an upper limit on the width. For example, the width may be less than 6 millimeters. Exceeding this limit may cause the electrical contact to exhaust the space that can be properly used by mechanical engagement or liquid-tight sealing. Thus, a combination of upper and lower limits can provide a robust seal against undesirable variations in the assembly amount of the connection without degrading the performance of the connection. The exact width depends on the diameter of the tubular component 200 and the type of connection.

[0102] In certain cases, the width may be defined based on the thread lead and / or pitch of the male thread 21. Of course, since the male thread 21 engages with the female thread 31, the thread lead and / or pitch may be the same. In one example, the width may be within 25% of the thread lead and / or pitch. That is, if the thread lead and / or pitch is l, the width may be between 0.75l and 1.25l.

[0103] Generally, the male electrical contact 24 may have a width in the axial direction of the first tubular component 200, and the female electrical contact 34 may have a width in the axial direction of the second tubular component 300. In particular, this may be the width of each contact surface that contacts each other in the assembled configuration. The width of the female electrical contact 34 may be smaller than the width of the male electrical contact 24. Alternatively, the width of the male electrical contact 24 may be smaller than the width of the female electrical contact 34. In further examples, the width of the female electrical contact 34 may be approximately the same as the width of the male electrical contact 24. The widths of the male electrical contact 24 and the female electrical contact 34 contact each other to form an electrical connection. Each width is in the same direction as the direction in which the respective threads 21, 31 extend (without tapering of the threads 21, 31).

[0104] In an axial cross-section (i.e., a cross-section taken from a plane including the axial direction), the male electrical contact 24 (particularly its contact surface) may be substantially flat. That is, it is flat in the axial direction. This can be seen, for example, in Figure 1. Of course, the male electrical contact 24 extends circumferentially around the first tubular component and is therefore curved in a radial cross-section. In addition, or alternatively, the female electrical contact 34 may be substantially flat in an axial cross-section. Substantially flat may mean, for example, a deviation of ±10° or less from purely flat.

[0105] In other words, the male electrical contacts 24 and / or female electrical contacts 34, when viewed in an axial cross-section, may not substantially extend across the width or in a direction perpendicular to the width. That is, they may extend only in the axial direction.

[0106] In certain cases, the reliability of the electrical contact between the male electrical contact 24 and the female electrical contact 34 may be improved by elastically deflecting one contact toward the other in the assembly configuration. The figure shows the female electrical contact 34 as an elastically deformable contact, but it is equally expected that this could also be the male electrical contact 24, and therefore the following description can be applied to the male electrical contact 24.

[0107] In other words, the female electrical contact 34 may include a deformable element in its assembly configuration that is deflected toward the male electrical contact 24. Alternatively, the male electrical contact 24 may include a deformable element in its assembly configuration that is deflected toward the female electrical contact 34. The deformable element may be conductive itself and form part of the electrical contact between the male electrical contact 24 and the female electrical contact 24. For example, the deformable element may generally be a coil spring extending circumferentially around the first tubular component 200 or the second tubular component 300. The corresponding first conductor 22 or second conductor 32 can then make electrical contact with this deformable element.

[0108] In certain cases, deformable elements, such as coil springs, may be embedded in the elastomer seal 35 or otherwise permanently fixed. Alternatively, deformable elements, such as coil springs, may be held between the elastomer seal 35 and further components, such as anti-extension rings. These anti-extension rings may be non-conductive and help insulate the female electrical contacts 34 from the second tubular component 300.

[0109] Figures 2A and 2B show further examples of the first tubular component 200, which may be described herein in relation to the first tubular component 200 of Figures 1 and 2. Unless otherwise expressly specified, any feature of the first tubular component 200 of Figure 1 or 2 may be equally applicable to the first tubular component 200 of Figure 2A, and vice versa.

[0110] The first tubular component 200 in Figures 2A and 2B represents a sealing cover 23. This sealing cover 23 is coupled to the outer surface of the first tubular component 200 and covers the first conductor 22. Yes, it is possible. For example, the first conductor 22 may be located in a groove, and a sealing cover 23 may be provided over it. Such a sealing cover 23 can be used together with the first tubular component 200 shown in Figures 1 and 2.

[0111] The first tubular component 200 in Figures 2A and 2B has a male electrical contact 24. This male electrical contact 24 is generally smaller than the male electrical contact 24 of the first tubular component 200 in Figures 1 and 2. The male electrical contact 24 extends further circumferentially, but much less than around the entire circumference. The insulating material 25 may be provided as a circumferential band aligned with the contact surface 25. For example, a circumferential groove may exist around the first tubular component 200. The insulating material 25 may be inserted into this groove. The male electrical contact 24 may then be inserted into the top of this insulating material 25 within the groove. The groove may have a specific recessed section for receiving the electrical contact 24, as shown in Figure 2B.

[0112] The male electrical contact 24 communicates electrically with the first conductor 22, for example, at the end of the wire.

[0113] Further threaded joints 100 are shown in Figures 4-8. Unless otherwise specified, all features disclosed above in relation to the threaded joints 100 in Figures 1-3 are equally applicable to the threaded joints 100 in Figures 4-8, and vice versa.

[0114] In the threaded joint 100 shown in Figures 4-8, the second tubular component 300 shown in Figures 1-3 and described above in relation thereto has a box at each end and is hereafter referred to herein as the coupling 500. The end of the first tubular component 200 may be inserted into a box, and the end of a further tubular component 200 may be inserted into another box.

[0115] Such threaded joints 100, including the coupling 500, are known as threaded and coupling connections. Threaded and coupling connections are generally used with so-called full-length pipe joints, which are, in this specification, a first tubular component 200 and a further tubular component 200, having pins at both ends. The further tubular component 200 may be identified using the nomenclature of the second tubular component, which, as stated above, may also be used to refer to the coupling 500.

[0116] An alternative to threaded and coupling connections is a so-called integral connection, which is generally used with so-called full-length pipe joints having a pin at one end and a box at the other end. In integral connections, the full-length pipe joints are connected directly, whereas in threaded and coupling connections described below herein, the full-length pipe joints are connected by couplings.

[0117] Coupling 500 is suitable for use in threaded joints 100. Coupling 500 may be particularly suitable for use in casing strings or tubing strings. Any reference to “casing string” in this disclosure should be understood to be equally applicable to tubing strings. Casing strings or tubing strings may be used for many different operations, including but not limited to production and injection.

[0118] The coupling 500 functions to connect the first tubular component 200 and the further tubular component 200 together. Although Figure 4 shows the tubular components 200 as being substantially identical, this is not necessarily the case (although it may be preferable), and there may be variations between the first tubular component 200 and the further tubular component 200. In detail, any features described herein may apply to only one of these tubular components 200. It should be understood that any reference to each tubular component 200 means that, in this context, each may independently possess the characteristics described. The coupling 500 and the threaded joint 100, including the first tubular component 200 and the further tubular components 200, may be part of a casing string or tubing string.

[0119] The coupling 500 may have an axial length of 20 inches or less. In certain examples, this may be 12 inches or less. The coupling 500 may have an axial length of 5 inches or more, for example, 7 inches or more. For example, the coupling 500 may have an axial length in the range of 7 inches to 12 inches.

[0120] The axial direction may be understood as the center line passing along the length of the coupling 500. The coupling 500 may generally be a hollow cylinder with defined axial, radial, and hoop directions. The axial direction is the line passing through the center of each base of the cylinder.

[0121] Each tubular component 200 may be identical or generally similar to the first tubular component 200 in Figures 1-3.

[0122] Each tubular component 200 may have a first end region at one end and a second end region at the opposite end. The first and second end regions may be substantially similar to, identical to, or different from each other.

[0123] Each tubular component 200 includes a pin. The pin has an outer surface on which a male thread 21 is formed. The first tubular component 200 may be generally cylindrical. Each male thread 21 may be positioned in the assembly configuration for engagement with the corresponding female thread of the coupling 500.

[0124] The male electrical contacts 24 extend circumferentially around each tubular component 200, particularly around the outer surface of the pins. These male electrical contacts 24 may extend only a small amount circumferentially, e.g., less than 20° of the circumference. In other examples, the male electrical contacts 24 may extend around the entire circumference or a portion of the circumference of each tubular component 200. References to each tubular component 200 imply tubular components 200 with or associated with further features.

[0125] Each male screw 21 may be located between the male electrical contact 24 and each tubular component 200, particularly the end of the pin. In other words, the end region of each tubular component 200 may, in order, include the end, the male screw 21, and then the male electrical contact 24. This configuration may be located at one end of the first tubular component 200 or at both ends of the first tubular component 200 (i.e., the first end region and the second end region). These elements may be directly adjacent to each other, or there may be a space between them. The end in this sense is the end closest to the male electrical contact 24, that is, not the end on the opposite end of the tubular component 200, which would not be in the same end region.

[0126] Each electrical contact 24 is insulated from its respective tubular component 200. That is, each male electrical contact 24 may be electrically insulated from and / or insulated from its respective tubular component 200. For example, a male electrical contact 24 may be a conductive ring extending circumferentially around a tubular component 200. An insulator, such as an elastomer ring, may be provided between each male electrical contact 24 and its respective tubular component 200 to electrically insulate the electrical contact 24 from its respective tubular component 200.

[0127] The conductor 22 may extend along each tubular component 200, for example, in the axial direction. Each conductor 22 communicates electrically with each male electrical contact 24. Each conductor 22 may extend precisely axially, as shown in Figure 4. However, in further examples, each conductor 22 may deviate from this purely axial path. For example, each conductor 22 may also have circumferential and / or radial deviations from the purely axial path.

[0128] Each conductor 22 is electrically insulated from its respective tubular component 200. For example, each conductor 22 may be in the form of a wire having a conductive core covered with a non-conductive sheath. Alternatively, an insulator may be provided between each conductor 22 and its respective tubular component 200.

[0129] In certain examples, each tubular component 200 may include grooves or recesses formed on its outer surface. These can be formed by either machining or milling the outer surface. The grooves may be curved in cross-section; that is, the grooves may not contain sharp corners that could act as stress concentration areas. In certain examples, the grooves may have a U-shaped cross-section. For example, the grooves may have a radius of curvature of less than 5 millimeters. In certain examples, the radius of curvature of the grooves may be between 1 and 2 millimeters.

[0130] Each conductor 22 may extend into its respective groove. For example, the conductor 22 does not extend beyond the outer circumference of the outer surface. That is, each tubular component 200 does not have a larger outer diameter as a result of the introduction of the conductor 22.

[0131] To further protect the conductor 22 from external influences of the underground environment, a sealing cover 23 may be provided. This sealing cover 23 may be bonded to the outer surface of a tubular component 200 to cover the conductor 22. For example, the conductor 22 may be located in a groove over which a sealing cover is provided.

[0132] These first tubular components 200 and further tubular components 200 are each connected to a coupling 500 to form each threaded joint 100.

[0133] The coupling 500 may be symmetrical with respect to a radial plane passing through its axial center. That is, the first end of the coupling 500 may be identical to the second end of the coupling 500.

[0134] Figure 5 shows a cross-section of a coupling 500 having a first tubular component 200 and a further tubular component 200 that engages with it. The coupling may be substantially cylindrical. The coupling 500 includes a tubular body. This body has a first end and a second end. The first and second ends are the opposite ends of the elongated tubular body. Each end of the body includes a box. The box has an inner surface on which female threads 51 are formed. The surface as an inner surface faces inward toward the central axis direction of the coupling 500. In other words, the surface is radially oriented. The inner surface extends axially along the coupling 500. The male threads 21 of the first tubular component 200 and the further tubular component 200 are configured to engage with these female threads 51 in the assembled configuration.

[0135] The first female electrical contact 54 extends circumferentially around the inner surface of the coupling 500, particularly the box, at the first end of the coupling 500. In certain examples, the first female electrical contact 54 may extend around the entire circumference of the coupling 500, or around a portion of the circumference.

[0136] The first female electrical contact 54 may be axially misaligned with the female screw 51. For example, the first female electrical contact 54 may be located between the corresponding sealing surface and the female screw 51. In other words, the end regions of the coupling 500 (for example, the first end region shown in the figure) are, in order, The configuration may include an end, a corresponding sealing surface, a first female electrical contact 54, and then a first female screw 51. This configuration may be located at one end of the coupling 500 or at both ends of the coupling 500 (i.e., a first end region and a second end region). These elements may be directly adjacent to each other, or there may be a space between them. In this sense, the end is the end closest to the first female electrical contact 54, i.e., not the end on the opposite end of the coupling 500, which would not be in the same end region.

[0137] The second female electrical contact 54 extends circumferentially around the inner surface of the coupling 500, particularly the box, at the second end of the coupling 500. In certain examples, the second female electrical contact 54 may extend around the entire circumference of the coupling 500, or around a portion of the circumference. The second female electrical contact 54 may be identical to the first female electrical contact 54, or there may be differences between each female electrical contact 54.

[0138] The second female electrical contact 54 may be axially offset from the female screw 51. For example, the second female electrical contact 54 may be located between the corresponding sealing surface and the female screw 51. In other words, the end region of the coupling 500 (e.g., the illustrated second end region) may, in order, include the end, the corresponding sealing surface, the second female electrical contact 54, and then the second female screw 51. This configuration may be located at one end of the coupling 500 or at both ends of the coupling 500 (i.e., the second end region and the first end region). These elements may be directly adjacent to each other, or there may be a space between them. In this sense, the end is the end closest to the second female electrical contact 54, that is, not the end on the opposite end of the coupling 500, which would not be in the same end region.

[0139] Each female electrical contact 54 is insulated from the tubular body of the coupling 500. For example, each female electrical contact 54 may be at least partially insulated from the coupling 500 by an elastomer seal. This elastomer seal may contact the corresponding tubular component 200, particularly the pin, to form a seal with the corresponding tubular component 200. This may be part of an interference seal or an internal seal.

[0140] The first female electrical contact 54 and the second female electrical contact 54 each have a female contact surface that has a width in the axial direction of the coupling 500. This contact surface is the exposed surface of each electrical contact 54 that forms an electrical contact. A longitudinal conductor 52 is included in the coupling 500. The longitudinal conductor 52 may be a single continuous conductor, such as a single wire, or it may consist of one or more elements that communicate electrically with one another. The longitudinal conductor 52 is electrically communicated with each of the female electrical contacts 54. For example, the longitudinal conductor 52 may extend between the first electrical contact 54 and the second electrical contact 54.

[0141] The longitudinal conductor 52 is insulated from the tubular body of the coupling 500. For example, the longitudinal conductor 52 may be in the form of a wire (or a series of connecting wires) having a conductive core covered with a non-conductive covering. Alternatively or additionally, an insulator may be provided between the longitudinal conductor 52 and the tubular body of the coupling 500.

[0142] The coupling 500 includes a conductive hole extending through a tubular body and a longitudinal conductor 52 extending through this conductive hole.

[0143] The conductor hole includes a longitudinally extending hole 56. The longitudinally extending hole 56 is formed within the tubular body. The longitudinally extending hole 56 may extend over most of the longitudinal length of the coupling 500. In certain examples, the longitudinally extending hole 56 may be formed between the radially inner and outer surfaces of the coupling 500. The longitudinally extending hole 56 is shown in Figure 5. As shown, the holes may extend only in the longitudinal direction. The longitudinal direction is generally parallel to the axial direction of the coupling 500. However, in further examples, holes 56 that extend in the longitudinal direction may also extend in other directions, such as the radial direction.

[0144] The coupling 500, particularly the conductor hole, may include a hole 57 extending in a first radial direction at the first end. The first radial hole 57 is formed within the tubular body. The first radial hole 57 extends from or near the first female electrical contact 54 to a longitudinal hole 56. In certain cases, the first radial hole 57 may extend strictly in the radial direction only, i.e., it may not have any longitudinal range. However, as shown in Figure 5, the first radial hole 57 may also extend in the longitudinal direction.

[0145] The coupling 500, particularly the conductor hole, may include a second radially extending hole 57 at the second end. The second radially extending hole 57 is formed within the tubular body. The second radially extending hole 57 extends from or near the second electrical contact 54 to a longitudinally extending hole 56. In certain cases, the second radially extending hole 57 may extend strictly radially only, i.e., it may not have a longitudinal range. However, as shown in Figure 5, the second radially extending hole 57 may also extend longitudinally.

[0146] Collectively, the longitudinally extending holes 56 and the radially extending holes 57 may define a continuous passage from the first electrical contact 54 through the tubular body to the second electrical contact 54. This continuous passage is a conductive hole.

[0147] Collectively, the conductor hole is formed from a longitudinally extending hole 56 and, if present, a radially extending hole 57. This conductor hole spans between the first female electrical contact 54 and the second female electrical contact 54. As a result, the longitudinal conductor 52 extends along the conductor hole from the first female electrical contact to the second female electrical contact alone. That is, the longitudinal conductor 52 can extend along the conductor hole and connect the first female electrical contact 54 to the second female electrical contact 54 without occupying the hole. The longitudinal conductor 52 is spaced apart from the outer surface and / or inner surface of the coupling 500 along its entire length.

[0148] The manufacture of the coupling 500, and in particular the longitudinally extending holes 56, will be discussed in more detail below. However, the longitudinally extending holes 56 may be formed as blind holes. Such blind holes may have an opening at the opposite end. An example of a longitudinally extending hole 56 is shown in Figure 5.

[0149] The longitudinally extending hole 56 can be machined within the tubular body. For example, this may be done by drilling, electrical discharge machining (EDM), and / or milling into the coupling 500. As shown in Figure 6, a plug 58 may be provided to close the opening of the hole. This plug 58 may be positioned to seal the longitudinally extending hole 56. This can prevent fluids, such as drilling fluid, from entering the longitudinally extending hole 56.

[0150] Similarly, a first radially extending hole and a second radially extending hole may be machined into the tubular body at the first and second ends, respectively. Again, this may be done by drilling, electrical discharge machining (EDM), and / or milling into the coupling 500.

[0151] In the assembly configuration, the male threads 21 of each pin of each tubular component 200 and the corresponding female threads 51 of the box of the coupling 500 may engage with each other. That is, the male threads 21 of the pins may be screwed into the corresponding female threads 31 of the box to form the assembly configuration. This forms a screw joint 100. In this assembly configuration, each male electrical contact 24 is in electrical contact with the corresponding female electrical contact. In this sense, a continuous electrical connection can be formed between the male electrical contacts 24 of the first tubular component 200, through the first female electrical contact 54, through the longitudinal conductor 52, through the second female electrical contact 54, and to the male electrical contacts 24 of further tubular components 200. This is all in the assembly configuration. In detail, these are the female contact surfaces of the first and second female electrical contacts 54 that contact each male electrical contact 24.

[0152] The male thread 21 and female thread 51 may be any suitable type of screw for forming the threaded joint 100. In certain examples, the male thread 21 and female thread 51 may be or include screws with varying thread widths, also known as wedge screws or self-locking screws; that is, screws whose axial width increases along their length.

[0153] In certain cases, the reliability of the electrical contacts between each male electrical contact 24 and each corresponding female electrical contact 54 may be improved by allowing one or both of the contacts to elastically deflect toward the other in the assembly configuration. The figure shows the female electrical contact 54 as an elastically deformable contact, but it is equally expected that this could be the male electrical contact 24, or both.

[0154] In other words, each female electrical contact 54 may include a deformable element in the assembly configuration that is deflected toward the corresponding male electrical contact 24. Alternatively, each male electrical contact 24 may include a deformable element in the assembly configuration that is deflected toward the corresponding female electrical contact 54. The deformable element may be conductive itself and form part of the electrical contact between each male electrical contact 24 and the female electrical contact 54. For example, the deformable element may generally be a coil spring extending circumferentially around the first or further tubular component 200 or coupling 500. The corresponding first conductor 22 or longitudinal conductor 52 can then make electrical contact with this deformable element.

[0155] The longitudinal conductor 52 may be a single component, such as a single wire, which may be difficult to mount within the coupling 500. Instead, the longitudinal conductor 52 may include a first wire 52A and a second wire 52B and either connector, as discussed below. Such an arrangement may be most commonly seen in Figures 6-8. The first wire 52A and the second wire 52B may be coupled to each other so that they communicate electrically. This coupling may be within a longitudinally extending hole 56. Each wire may include a conductive core surrounded by a non-conductive covering along most of its length.

[0156] In certain examples, the first wire 52A is coupled to the second wire 52B using a connector 600. The connector 600 may be located within a longitudinally extending hole 56. The connector 600 may be any suitable connector that enables an electrical connection between the first wire 52A and the second wire 52B. A specific example of the connector 600 is shown in Figure 8. The connector 600 may be thermally activated in several forms; that is, the application of heat causes the connector 600 to change into several forms to couple the first wire 52A and the second wire 52B. The connector 600 may extend along the entire length of the longitudinally extending hole 56, the first radially extending hole 57, and the second radially extending hole 57, or only a portion thereof.

[0157] The connector 600 in Figure 8 may include a solder sleeve 62. This solder sleeve 62 is a certain amount of conductive material that melts when heated. When the solder sleeve 62 melts, it separates the first wire 52A and the second wire 52B, in particular each of the wires 52A and 52B. Connect the conductive core of B electrically.

[0158] During use, the first wire 52A and the second wire 52B may be inserted into the connector 600 located inside the longitudinal hole 56 of the coupling 500. The coupling 500, including the connector 600, may be heated so that the solder sleeve 62 melts, thereby bonding the first wire 52A to the second wire 52B.

[0159] In addition, or alternatively, the connector 600 in Figure 8 may include heat-shrink tubing 64, that is, tubing 64 that shrinks in its inner diameter when heat is applied. In certain examples that include both heat-shrink tubing 64 and solder sleeve 62, the solder sleeve 62 may be located inside the heat-shrink tubing 65. For example, the solder sleeve 62 may be located in the longitudinal center of the heat-shrink tubing 65.

[0160] During use, the first wire 52A and the second wire 52B may be inserted into the connector 600 inside the longitudinal hole 56 of the coupling 500. The coupling 500, including the connector 600, may be heated so that the heat-shrinkable tubing 64 shrinks, thereby holding the first wire 52A and the second wire 52B together, and thereby coupling the first wire 52A to the second wire 52B.

[0161] In this sense, the first wire 52A and the second wire 52B can be coupled together electrically (via the solder sleeve 62) and / or mechanically (via the heat-shrink tubing 64).

[0162] The connector 600 may additionally or alternatively include an adhesive 66. For example, as shown in Figure 8, there may be a first adhesive 66 at one end of the connector 600 and a second adhesive 66 at the second end on the opposite side of the connector 600. The adhesive can further assist in attaching the first wire 52A and the second wire 52B. The adhesive 66 may be heat-activated.

[0163] In certain examples that include both heat-shrink tubing 64 and adhesive 66, the adhesive 66 may be located inside the heat-shrink tubing 65. For example, the adhesive 66 may be located at both ends of the heat-shrink tubing 65. In certain examples that further include solder sleeves 62, the solder sleeves 62 may also be located inside the heat-shrink tubing 65. For example, the solder sleeves 62 may be located in the longitudinal center of the heat-shrink tubing 65, and the adhesive 66 may be located at both ends of the heat-shrink tubing 65 on either side of the solder sleeves 62.

[0164] To manufacture a coupling 500 used in a threaded joint 100, a tubular body may be formed together with a first end and a second end. Each end has a box having an inner surface on which female threads 51 are formed for engaging with a pin of the tubular component 200. A longitudinally extending hole 56 is then drilled or otherwise machined into the tubular body. An insulated conductor 52 is then inserted into the longitudinally extending hole 56. This insulated conductor 52 electrically communicates with the first female electrical contact 54 and the second female electrical contact 54.

[0165] The first female electrical contact 54 extends circumferentially around the inner surface of the coupling 500, particularly the box, at the first end of the coupling 500. In certain examples, the first female electrical contact 54 may extend around the entire circumference of the coupling 500, or around a portion of the circumference.

[0166] The second female electrical contact 54 extends circumferentially around the inner surface of the coupling 500, particularly the box, at the second end of the coupling 500. In a particular example, the second female electrical contact 5 4 may extend around the entire circumference of coupling 500, or around a portion of its circumference.

[0167] In examples where the insulating conductor 52 includes a first wire 52A and a second wire 52B, this can be an advantage in the manufacturing process. In particular, the first wire 52A may be inserted into a hole 56 extending longitudinally from a first end of the tubular body, for example, through a first radially extending hole 57. The second wire 52B may be inserted into a hole 56 extending radially from a second end of the tubular body, for example, through a second radially extending hole 57. This insertion may result in the first wire 52A and the second wire 52B being in electrical contact with each other. For example, they may be in contact within the longitudinally extending hole 56.

[0168] If the coupling 500 further includes a connector 600, this connector 600 may first be placed in a longitudinally extending hole 56. Then the first wire 52A is inserted into the connector 600, and then the second wire 52B is inserted into the connector 600. The connector 600 may be thermally activated in several forms. That is, the application of heat causes the connector 600 to change into several forms to couple the first wire 52A and the second wire 52B. Then the coupling 600, for example a tubular body, may be heated to activate the connector 600, thereby coupling the first wire 52A to the second wire 52B. This coupling means that the first wire 52A and the second wire 52B are electrically communicating with each other.

[0169] The connector 600 may be as described above and may include one or more of the solder sleeve 62, heat shrink tubing 64, and / or adhesive 66.

[0170] In certain examples, the first female electrical contact 54 may be fixed to the first wire 52A before the first wire 52A is inserted into the longitudinally extending hole 56. For example, the first wire 52A may be embedded in the first female electrical contact 54 or otherwise permanently attached. In certain examples, the first female electrical contact 54 may be insulated from the tubular body via an elastomer insulator. This elastomer insulator may be molded, for example, by injection molding, to embed the first wire 52A and a portion of the first female electrical contact 54, thereby coupling the first wire 52A to the first female electrical contact 54.

[0171] The first wire 52A can be cut to the required length so as to reach the connector 600 in the longitudinally extending hole 56.

[0172] This fastening of the first wire 52A to the first female electrical contact 54 may be done during manufacturing or may have already been done in another process prior to manufacturing the coupling 500.

[0173] In certain examples, the second female electrical contact 54 may be fixed to the second wire 52B in the same manner. That is, the second female electrical contact 54 may be fixed to the second wire 52B before the second wire 52B is inserted into the longitudinally extending hole 56. For example, the second wire 52B may be embedded in the second female electrical contact 54 or otherwise permanently attached. In certain examples, the second female electrical contact 54 may be insulated from the tubular body via an elastomer insulator. This elastomer insulator may be molded, for example, by injection molding, to embed the second wire 52B and a portion of the second female electrical contact 54, thereby coupling the second wire 52B to the second female electrical contact 54.

[0174] The second wire 52B can be cut to the required length so as to reach the connector 600 in the longitudinally extending hole 56.

[0175] This fastening of the second wire 52B to the second female electrical contact 54 may be done during manufacturing or may have already been done in another process prior to the manufacture of the coupling 500.

[0176] In general, these assemblies of the first female electrical contact 54 and the first wire 52A, and the second female electrical contact 54 and the second wire 52B, may be identical to one another. Alternatively, there may be differences, for example, the direction in which each wire 52A, 52B extends away from the female electrical contact 54.

[0177] The first radially extending hole 57 may be drilled at the first end of the coupling 500 or otherwise machined. The first radially extending hole 57 extends from the inner surface into a longitudinally extending hole 56.

[0178] The second radially extending hole 57 may be drilled or otherwise machined at the second end of the coupling 500, which is opposite the first end. The second radially extending hole 57 extends from the inner surface into a longitudinally extending hole 56. The insulating conductor 52 is inserted through both the radially extending hole 57 and the longitudinally extending hole 56.

[0179] In certain examples, the longitudinally extending hole 56 may be a blind hole having a blind hole at one end and an open hole at the opposite end. The open hole at the opposite end may be closed, and the method may include a corresponding step of closing the open hole with, for example, a plug 58. This closes the open hole, which may help prevent the perforating fluid from entering the longitudinally extending hole 56. In further examples, the longitudinally extending hole 56 may be a through hole with open holes at both ends. One of these open holes can then be closed to effectively form a blind hole. The other, opposite open hole can then be closed in the same manner as described above.

[0180] If connector 600 is used, it may be inserted before the opening is closed. For example, connector 600 may be inserted through the opening and positioned within the longitudinally extending hole 56. Once connector 600 is in place, the opening is then closed.

[0181] Closing the opening means that the perforating fluid and other materials can be prevented from entering the longitudinally extending hole 56.

[0182] In this sense, a coupling 500 can be formed. This coupling 500 can then be used to form a threaded joint 100 by assembling the two tubular components 200 to the coupling 500 as described above.

[0183] Generally, strings for wells are also provided. These strings include a plurality of tubular components 200, 300. These tubular components 200, 300 may be as described above. The plurality of tubular components 200, 300 are assembled by threaded engagements to form a casing string or tubing string. For example, the string may include a plurality of threaded fittings as described above.

[0184] One or more sensors are positioned along this casing string or tubing string. These sensors may be temperature sensors, pressure sensors, accelerometers, magnetometers, ultrasonic sensors, flow sensors, acoustic sensors, or any other type of sensor.

[0185] Each of the tubular components 200, 300 includes a hole or groove extending in the longitudinal direction. This hole or groove may be formed on the outer surface of the tubular components 200, 300. This can be formed by any method, including machining or milling into the outer surface. The groove preferably includes a curved surface in cross-section. That is, the groove may not include a sharp corner that could act as a stress concentration area. The groove may be fully curved or may include a curved base and a straight wall. In certain examples, the groove may be U-shaped in cross-section. For example, the base of the groove may have a radius of curvature of less than 5 millimeters. In certain examples, the radius of curvature of the base of the groove may be 1 to 2 millimeters. The groove extends in the longitudinal direction, but this is not necessarily limited to the longitudinal direction. The groove may extend in other directions.

[0186] These grooves may be provided particularly on the outer surfaces of each tubular component 200, 300.

[0187] Conductors 22 and 32 are provided within these holes or grooves and are electrically insulated from the tubular components 200 and 300. For example, each conductor 22 and 32 may be in the form of a wire having a conductive core covered with a non-conductive covering. Alternatively, an insulator may be provided between each conductor 22 and 32 and each of the tubular components 200 and 300.

[0188] At the first end of each tubular component 200, 300 is a first electrical contact 24, 34, and at the second end of each tubular component 200, 300 is a second electrical contact 24, 34. During use, the electrical contacts 24, 34 of adjacent tubular components 200, 300 may come into contact with each other in the assembled configuration.

[0189] Collectively, the conductors 22, 32 of the multiple tubular components 200, 300 are electrically communicated with one another, for example, via electrical contacts, so that they form a continuous conductive path. Each of the sensors is then electrically communicated with this conductive path.

[0190] In certain cases, there may be only a single conductive path defined by conductors 22 and 32. This single conductive path can be used for both transmitting power to one or more sensors and receiving signals from one or more sensors. For example, there may be substantially constant power supplied along the conductive path, and a variable response signal may be superimposed on this constant power signal. Any other suitable electronic and / or signal processing system may also be used for this power and signal transmission.

[0191] In this sense, the string can communicate with the underground sensor to communicate the underground conditions on the surface. The tubular components 200, 300 may be as described herein. Furthermore, the string may include a coupling 500 such as those described above.

[0192] One or more of the tubular components 200 may include a pin at a first end, the pin having an outer surface on which a male thread 21 is formed. The male thread 21 may be located between the first electrical contact 24 and the end of the tubular component 200.

[0193] One or more of the tubular components 300 may include a box at a second end, the box having an inner surface on which a female thread 31 is formed. The second electrical contact 34 may be located between the female thread 31 and the end of the second tubular component 300. In certain examples, the same tubular components 200, 300 may have a pin at one end and a box at the other end.

[0194] The string is not a perforated string, but specifically a casing string or tubing. It may be a string. In this sense, each tubular component may be a casing or a tubular component.

[0195] All examples and embodiments described above refer to the connection of a single conductive path. In further examples, multiple conductive paths may be formed across the threaded joint. To avoid doubt, this may also apply to the threaded joint 100 in Figure 1, or the further threaded joint 100 in Figure 4, or any other threaded joint 100. Figures 9A and 9B show such electrical connections of multiple conductive paths. Figures 9A and 9B show this electrical connection of the threaded joint 100 of the first tubular component 200 and the second tubular component 300, but the electrical connection may be used equally for any of the above threaded joints 100, in particular the further threaded joint 100 in Figure 4.

[0196] In general, the engagement between the first tubular component 200 and the second tubular component 300 is as described above. However, multiple male electrical contacts 24a to 24d are provided along with a corresponding number of female electrical contacts 34a to 34d. "Corresponding" means that in some examples, the number of male electrical contacts 24a to 24d is the same as the number of female electrical contacts 34a to 34d. In other examples, the numbers of each may be different.

[0197] Each male electrical contact 24a to 24d may be insulated from the first tubular component 200. Each female electrical contact 34a to 34d may be insulated from the second tubular component 300.

[0198] Figures 9A and 9B show schematic diagrams of the assembly configuration. In these schematic diagrams, the male electrical contacts 24a to 24d are shown radially separated from the female electrical contacts 34a to 34d. In reality, the male electrical contacts 24a to 24d will be in contact with the female electrical contacts 34a to 34d in the assembly configuration. In fact, Figures 9A and 9B more accurately represent the assembly configuration, in part, as further engagement of the male screw 21 and female screw 31 is required for the assembly configuration.

[0199] Each male electrical contact 24a to 24d is spaced apart from each other in the circumferential direction around the first tubular component 200. In certain cases, the male electrical contacts 24a to 24d may have rotational symmetry around the outer surface of the first tubular component 200. That is, N male electrical contacts 24a to 24d may have N times rotational symmetry due to each male electrical contact 24a to 24d being spaced (360 / N)° apart from each other. Each male electrical contact 24a to 24d has a first circumferential length. Each male electrical contact 24a to 24d may have the same first circumferential length. Between each male electrical contact 24a to 24d, there is a first circumferential gap on the outer surface of the first tubular component 200.

[0200] Each male electrical contact 24a to 24d may be axially aligned with each other. Each male electrical contact 24a to 24d may be axially offset from the male screw 21. For example, the male screw 21 may be located between each male electrical contact 24a to 24d and the first tubular component 200, particularly the pin ends. In other words, the terminal region of the first tubular component 200 (e.g., the illustrated first terminal region) may, in order, include the terminal, the male screw 21, and then the male electrical contacts 24a to 24d. This configuration may be located at one end of the first tubular component 200 or at both ends of the first tubular component 200 (i.e., the first terminal region and the second terminal region). These elements may be directly adjacent to each other, or there may be a space between them. In this sense, the terminal is the terminal closest to the male electrical contacts 24a to 24d. In other words, it is not the end of the opposite end of the first tubular component 200, which would not be in the same terminal region.

[0201] Multiple first conductors 22 extend along the first tubular component 200, for example, in the axial direction. Each first conductor 22 may extend circumferentially apart from other first conductors 22. Alternatively, they may extend together in a bundle and then be separated. Each male electrical contact 24a to 24d communicates electrically with the corresponding first conductor 22. Each first conductor 22 may extend along the first tubular component 20 as described above. In this sense, each first conductor 22 may carry separate signals to and from each male electrical contact 24a to 24d.

[0202] Focusing on the second tubular component, each female electrical contact 34a to 34d is spaced apart from each other in the circumferential direction around the second tubular component 300. In certain cases, the female electrical contacts 34a to 34d may have rotational symmetry around the inner surface of the second tubular component 300. That is, N female electrical contacts 34a to 34d may have N times rotational symmetry due to each female electrical contact 34a to 34d being spaced (360 / N)° apart from each other. Each female electrical contact 34a to 34d has a second circumferential length. Each female electrical contact 34a to 34d may have the same second circumferential length. Between each female electrical contact 34a to 34d, there is a second circumferential gap on the inner surface of the second tubular component 300.

[0203] Each female electrical contact 34a to 34d may be axially aligned with one another. Each female electrical contact 34a to 34d may be axially offset from the female thread 31. For example, each female electrical contact 34a to 34d may be located between the female thread 31 and the second tubular component 300, particularly the end of the box. In other words, the end region of the second tubular component 300 (e.g., the illustrated first end region) may, in order, include the end, the female electrical contacts 34a to 34d, and then the female thread 31. This configuration may be located at one end of the second tubular component 300 or at both ends of the second tubular component 300 (i.e., the first end region and the second end region). These elements may be directly adjacent to each other, or there may be a space between them. In this sense, the end is the end closest to the female electrical contacts 34a to 34d. In other words, it is not the end of the opposite end of the second tubular component 300, which would not be in the same terminal region.

[0204] Multiple second conductors 32 extend along the second tubular component 300, for example, in the axial direction. Each second conductor 32 may extend circumferentially apart from other second conductors 32, or they may extend together in a bundle and then be separated. Each female electrical contact 34a to 34d communicates electrically with the corresponding second conductor 32. Each second conductor 32 may extend along the second tubular component 300 as described above. In this sense, each second conductor 32 may carry separate signals to and from each female electrical contact 34a to 34d.

[0205] With multiple male electrical contacts 24a-24d and multiple female electrical contacts 34a-34d, there is a risk of rotational misalignment connecting multiple contacts, which can cause problems such as short circuits. To address this, the first circumferential gap between each male electrical contact 24a-24d may be longer than the second circumferential length between each female electrical contact 34a-34d; and the second circumferential gap between each female electrical contact 34a-34d may be longer than the first circumferential length between each male electrical contact 24a-24d. This means that a single electrical contact cannot pass through the corresponding gap, thus avoiding the problem of rotational misalignment. Figure 9B schematically illustrates this arrangement (again, note that the electrical contacts are shown radially spaced apart for clarity. Each electrical contact will sit within its corresponding circumferential gap. This means that it is impossible for two male electrical contacts 24a-24d or two female electrical contacts 34a-34d to be connected to each other by other contacts.

[0206] Figures 9A and 9B show male electrical contacts 24a to 24d having a first circumferential length shorter than the second circumferential length of female electrical contacts 34a to 34d, but this is not necessarily the case, and the reverse is equally possible.

[0207] In this sense, the threaded joint 1 of the first tubular component 200 and the further tubular component 200 00 is resistant to rotational displacement and allows for multiple conductive paths.

[0208] This arrangement can be further combined such that each female electrical contact 34a-34d has a width that may be smaller than the width of each male electrical contact 24a-24d. Alternatively, the width of each male electrical contact 24a-24d may be smaller than the width of each female electrical contact 34a-34d. This provides resistance to axial misalignment as described above.

[0209] In the threaded joint 100 of Figure 4, these multiple connection arrangements are generally the same as those described above, with appropriate modifications.

[0210] The coupling 500 may include a first set of female electrical contacts on the inner surface of the first end of the coupling 500, and a second set of female electrical contacts on the inner surface of the second end of the coupling 500. Each female electrical contact may be insulated from the coupling 500.

[0211] Each female electrical contact of the first plurality of female electrical contacts is spaced apart from each other in the circumferential direction around the coupling 500. In certain cases, the first plurality of female electrical contacts may have rotational symmetry around the inner surface of the coupling 300. That is, N female electrical contacts in the first plurality of female electrical contacts may have N times rotational symmetry due to each female electrical contact of the first plurality of female electrical contacts spaced (360 / N)° apart from each other. Each female electrical contact of the first plurality of female electrical contacts has a second circumferential length. Each female electrical contact of the first plurality of female electrical contacts may have the same second circumferential length. Between each female electrical contact of the first plurality of female electrical contacts, there is a second circumferential gap on the inner surface of the coupling 500.

[0212] Each female electrical contact of the second set of female electrical contacts is spaced apart from each other in the circumferential direction around the coupling 500. In certain cases, the second set of female electrical contacts may have rotational symmetry around the inner surface of the coupling 300. That is, N female electrical contacts in the second set of female electrical contacts may result in N times rotational symmetry due to each female electrical contact of the second set of female electrical contacts being spaced (360 / N)° apart from each other. Each female electrical contact of the second set of female electrical contacts has a third circumferential length. Each female electrical contact of the second set of female electrical contacts may have the same third circumferential length. The third circumferential length may be the same as the second circumferential length. Between each female electrical contact of the second set of female electrical contacts, there is a third circumferential gap on the inner surface of the coupling 500. The third circumferential gap may be the same size as the second circumferential gap.

[0213] Each female electrical contact of the first set of female electrical contacts may be aligned axially with one another. Each female electrical contact of the second set of female electrical contacts may be aligned axially with one another.

[0214] Each female electrical contact of the first set of female electrical contacts may be electrically communicated with the corresponding electrical contact of the second set of female electrical contacts. For example, there may be separate longitudinal conductors 52 connecting each pair of female electrical contacts. These longitudinal conductors 52 may be as described above. Each longitudinal conductor 52 may extend along a hole 56 that extends in its own longitudinal direction. Alternatively, multiple longitudinal conductors 52 may be located within the same longitudinally extending hole 56.

[0215] With respect to the threaded joint 100 in Figure 4, each tubular component 200 may be identical or generally similar to the first tubular component 200 described herein with reference to Figures 1 to 3 in particular.

[0216] Each tubular component 200 may further include a plurality of male electrical contacts 24a to 24d on the outer surface of the end region of the first tubular component 200. Each male electrical contact 24a to 24d may be insulated from the tubular component 200.

[0217] Each male electrical contact 24a to 24d is spaced apart from each other in the circumferential direction around the tubular component 200. In certain cases, the male electrical contacts 24a to 24d may have rotational symmetry around the outer surface of the tubular component 200. That is, N male electrical contacts 24a to 24d may have N times rotational symmetry due to each male electrical contact 24a to 24d being spaced (360 / N)° apart from each other. Each male electrical contact 24a to 24d has a first circumferential length. Each male electrical contact 24a to 24d may have the same first circumferential length. Between each male electrical contact 24a to 24d, there is a first circumferential gap on the outer surface of the tubular component 200.

[0218] Each male electrical contact 24a to 24d may be axially aligned with each other. Each male electrical contact 24a to 24d may be axially offset from the male screw 21. For example, the male screw 21 may be located between each male electrical contact 24a to 24d and the tubular component 200, particularly the end of the pin. In other words, the end region of the tubular component 200 (e.g., the first end region shown in the figure) may, in order, include the end, the male screw 21, and then the male electrical contacts 24a to 24d. This configuration may be located at one end of the tubular component 200 or at both ends of the tubular component 200 (i.e., the first end region and the second end region). These elements may be directly adjacent to each other, or there may be a space between them. The end in this sense is the end closest to the male electrical contacts 24a to 24d, that is, not the end on the opposite end of the tubular component 200 which would not be in the same end region.

[0219] In this sense, the coupling 500 and each tubular component 200 can form a threaded joint that allows for multiple conductive paths and is resistant to rotational shear. The embodiments and examples are deemed to be shown in the following numbered clauses: A1. A threaded joint, A first and second tubular component, wherein the first tubular component includes a pin having an outer surface on which a male thread is formed at a first end region and a second end region on the opposite side, and the second tubular component includes a box having an inner surface on which a female thread is formed at the first end region and a second end region on the opposite side, and the male thread is arranged in the assembly configuration to engage with the female thread; A male electrical contact insulated from the first tubular component, located on the outer surface of the first terminal region of the first tubular component; A female electrical contact insulated from the second tubular component, on the inner surface of the first terminal region of the second tubular component; A first conductor extending along the first tubular component, communicating with the male electrical contact, and insulated from the first tubular component; A second conductor extending along the second tubular component, communicating with the female electrical contact, and insulated from the second tubular component. Equipped with, The male and female electrical contacts are arranged in the assembly configuration so as to be in contact with each other. A screw fitting in which the male electrical contact has width in the axial direction of the first tubular component, and the female electrical contact has width in the axial direction of the second tubular component, and the width of the female electrical contact is smaller than the width of the male electrical contact, or vice versa. A2. A threaded joint according to clause A1, without a shoulder portion. A3. A threaded fitting according to clause A1 or A2, wherein the contact surfaces of the male and female electrical contacts are arranged to be in contact with each other in the assembled configuration, the width of the male electrical contact is the width of the male contact surface, and the width of the female electrical contact is the width of the female contact surface. A4. A threaded fitting according to any of clauses A1 to A3, wherein the male and / or female electrical contacts are substantially flat in the axial direction in an axial cross-section. A5. A threaded fitting according to any of the clauses A1 to A4, wherein the male thread is located between the male electrical contact and the end of the first terminal region of the first tubular component. A6. A threaded fitting according to any of the clauses A1 to A5, wherein the female electrical contact is located between the female thread and the end of the first terminal region of the second tubular component. A7. Male electrical contacts extend circumferentially around the outer surface; and / or The female electrical contact extends circumferentially around the inner surface. A threaded fitting according to any of clauses A1 to A6. A8. The first tubular component includes a groove formed on its outer surface, and the first conductor extends into the groove; and / or The second tubular component includes a groove formed on its outer surface, and the second conductor extends into the groove. Threaded fittings of any of clauses A1 to A7 A9. A threaded fitting according to clause A8, wherein the groove includes a curved surface in cross-section, and preferably the groove is U-shaped. A10. A threaded fitting of clause A9, wherein the groove has a radius of curvature of less than 5 mm, preferably 1 mm to 2 mm. A11. A threaded fitting of any of the clauses A8 to A10, further comprising a sealing cover bonded to the outer surface of the groove. A12. A threaded fitting according to any of the clauses A8 to A11, wherein the first tubular component includes a groove formed on its outer surface, the first conductor extends within the groove, and the groove communicates with a hole beneath the sealing surface of the first tubular component. A13. A threaded fitting of any of clauses A1 to A12, with a male electrical contact width greater than 3 millimeters. A14. A threaded fitting of any of clauses A1 to A13, where the width of the male electrical contact is less than 6 millimeters. A15. A threaded fitting according to any of clauses A1 to A14, wherein the width of the male electrical contact is within 25% of the threaded lead or pitch. A16. A plurality of male electrical contacts, each insulated from the first tubular component, on the outer surface of the first end region of the first tubular component, having a first circumferential length and spaced apart from each other by a first circumferential gap; A plurality of female electrical contacts on the inner surface of the first end region of a second tubular component, each insulated from the second tubular component, having a length of the second circumferential direction and spaced apart from each other by a gap of the second circumferential direction; A plurality of first conductors extending along the outer surface of a first tubular component, each of which communicates with a corresponding male electrical contact of a plurality of male electrical contacts and is insulated from each of the first tubular components; and A plurality of second conductors extending along a second tubular component, each second conductor communicating with a corresponding female electrical contact of a plurality of female electrical contacts and being insulated from each second tubular component. Furthermore, The first circumferential length is smaller than the second circumferential gap; The second circumferential length is smaller than the first circumferential gap. A threaded fitting according to any of clauses A1 to A15. A17. A threaded fitting according to any of the clauses A1 to A16, wherein the male electrical contact forms at least a portion of the interference seal of the first tubular component. A18. A threaded fitting according to any of the clauses A1 to A17, wherein the female electrical contact is insulated at least partially from the second tubular component by an elastomer seal for sealing by pins. A19. A threaded fitting according to any of the clauses A1 to A18, wherein the female electrical contact includes a deformable element that is deflected toward the male electrical contact in the assembly configuration, or vice versa. A20. A threaded joint according to clause A19, wherein the deformable element is a coil spring extending in the circumferential direction. A21. A threaded fitting according to any of the clauses A1 to A20, wherein the male and female threads include or are wedge threads. A22. Threaded fittings of clause A21, where the assembly configuration is uncertain. A23. A threaded fitting according to any of clauses A1 to A22, wherein the pin includes an annular sealing surface for sealing by interference with a complementary annular sealing surface of the box, and the annular sealing surface of the pin is located between the male thread and the end of the first tubular component. A24. A threaded fitting according to any of the clauses A1 to A23, wherein the first tubular component is a first casing or tubing component, and the second tubular component is a second casing or tubing component. A25. A string for a well, Multiple screw fittings by any of clauses A1 to A24, screw-engaged to form a string, such that the first and second conductors collectively form a conductive path; One or more sensors that communicate with a conductive path, positioned along the string. A string equipped with this feature. A26. The string of clause A25, where the conductive path is for transmitting power to one or more sensors and for transmitting signals from one or more sensors. A27. One or more sensors, Temperature sensor; Pressure sensor; accelerometer; Magnetometer; Ultrasonic sensor; Flow sensor; and / or Acoustic sensor A string in clause A25 or A26 that includes one or more of the following. A28. A string according to any of the clauses A25 to A27, wherein the string is a casing string or a tubing string, and each tubular component is a casing or tubing component. B1. A coupling for threaded joints, A tubular body having first and second ends, each end having a box having an inner surface thereon which a female thread is formed for engaging with a pin of a tubular component; A first female electrical contact, insulated from the tubular body, on the inner surface of the first end; A second female electrical contact insulated from the tubular body on the inner surface of the second end; and A longitudinal conductor that communicates with the first and second female electrical contacts and is insulated from the tubular body. Includes, A coupling comprising a tubular body having a conductive hole formed therein, which includes a hole extending in the longitudinal direction, through which a longitudinal conductor extends. B2. The first female electrical contact extends circumferentially around the inner surface; and / or The second female electrical contact extends circumferentially around the inner surface. Coupling of clause B1. B3. A coupling according to clause B1 or B2, wherein the conductor is formed from a first wire and a second wire joined to each other at positions within a hole extending in the longitudinal direction. B4. The coupling of clause B3, wherein the first wire is connected to the second wire using a connector in a longitudinally extending hole. B5. Coupling of clause B4, where the connector includes a solder sleeve. B6. Couplings of clause B4 or B5, where the connector includes heat-shrink tubing. B7. A coupling of any one of the clauses B1 to B6, wherein each female electrical contact includes a deformable element deflected toward the inside of the box. B8. The coupling of clause B7, wherein each deformable element is a coil spring extending in the circumferential direction. B9. A first plurality of female electrical contacts on the inner surface of a first end, each insulated from a tubular body, wherein the first plurality of female electrical contacts have a second circumferential length and are spaced apart from each other by a second circumferential gap; and A second plurality of female electrical contacts on the inner surface of the second end, each insulated from the tubular body, the second plurality of female electrical contacts having a third circumferential length and spaced apart from each other by a third circumferential gap, female electrical contacts A coupling of any of the prior claims, further including the following: B10. A coupling according to any one of the clauses B1 to B9, wherein each female electrical contact is insulated from the tubular body by an elastomer seal, and the female electrical contact and conductor are embedded within the seal and partially exposed to form the female electrical contact. B11. Any one of the couplings of clauses B1 to B10, wherein the conductor hole further includes, at the first end, a first radially extending hole extending from a first female electrical contact to a longitudinally extending hole, and at the second end, a second radially extending hole extending from a second female electrical contact to a longitudinally extending hole. B12. A coupling according to any one of the provisions B1 to B11, wherein the longitudinally extending hole has a blind hole with an opening at the first end of the tubular body. B13. The coupling of clause B12, wherein the longitudinally extending opening of the hole is closed with a plug. B14. A coupling in any of the terms B1 to B13, wherein the longitudinal conductor extends only along the conductor hole from the first female electrical contact to the second female electrical contact. B15. Any one of the couplings from clauses B1 to B14, wherein the longitudinal conductor is spaced apart from the outer and / or inner surface of the coupling along its entire length. B16. Any one of the couplings from clauses B1 to B15, wherein the axial length of the coupling is 20 inches or less, preferably 12 inches or less. B17. One coupling from any of the clauses B1 to B16, wherein the axial length of the coupling is 5 inches or more, preferably 7 inches or more. B18. Threaded joint, Any one of the couplings in clauses B1 to B17; A first tubular component and a further tubular component, each of which includes the following: A pin having an outer surface on which male threads are formed in a first terminal region, wherein each male thread is arranged in the assembly configuration to engage with a female thread of a coupling; The second terminal region on the opposite side; Male electrical contacts insulated from the tubular component, on the outer surface of the first terminal region of the tubular component; and A first conductor that extends along the tubular component, communicates with the male electrical contact, and is insulated from the tubular component. Equipped with, A screw fitting in which male and female electrical contacts are arranged to be in contact with each other in the assembly configuration. B19. A threaded fitting according to clause B18, wherein each male electrical contact extends circumferentially around the outer surface. B20. If subject to clause B9, each tubular component shall A plurality of male electrical contacts, each insulated from the tubular component, on the outer surface of the first end region of the tubular component, having a first circumferential length and spaced apart from each other by a first circumferential gap. It further includes, The first circumferential length is smaller than the second circumferential gap and the third circumferential gap; The circumferential lengths of 2 and the third circumferential length are smaller than the gap in the first circumferential direction. Threaded fittings under clause B18 or B19. B21. A threaded fitting according to any one of the provisions of B18 to B20, wherein the first tubular component is a first casing or tubing component, and the second tubular component is a second casing or tubing component. B22. A method for manufacturing a coupling for screw joints, A tubular body having first and second ends, each end having a box having an inner surface thereon which a female thread is formed for engaging with a pin of a tubular component; A hole extending in the longitudinal direction is machined through a tubular body; The invention involves inserting an insulated conductor into a longitudinally extending hole to communicate with a first female electrical contact and a second female electrical contact, wherein the first female electrical contact is located on the inner surface of the first end and is insulated from the tubular body, and the second female electrical contact is located on the inner surface of the second end and is insulated from the tubular body. Methods that include... B23. The first female electrical contact extends circumferentially around the inner surface; and / or The second female electrical contact extends circumferentially around the inner surface. The method of Clause B22. B24. The insulating conductor includes a first wire and a second wire, and the insulating conductor is inserted into a hole extending in the longitudinal direction. Inserting the first wire into a hole extending longitudinally from the first end of the tubular body; The method includes inserting the second wire into a hole extending longitudinally from the second end of the tubular body so that the first and second wires are electrically connected, The method of clause B22 or B23. B25. A step of positioning a connector in a longitudinally extending hole, wherein the step of inserting a first wire includes inserting the first wire into the connector, and the step of inserting a second wire includes inserting the second wire into the connector; A step of heating the tubular body to activate the connector and connecting the first wire to the second wire, The method of Clause B24, which further includes the method of Clause B24. B26. The connector includes a solder sleeve, as per clause B25. B27. The connector includes heat-shrink tubing, as per the method of clause B25 or B26. B28. One of the methods described in clauses B24 to B27, wherein the first female electrical contact is secured to the second wire before the first wire is inserted. B29. One of the methods described in clauses B24-B28, wherein the second female electrical contact is secured to the second wire before the second wire is inserted. B30. A process of machining a first radially extending hole at the first end into a longitudinally extending hole; A process of machining a second radially extending hole at the second end into a longitudinally extending hole, It further includes, One of the methods described in clauses B22 to B29, wherein the insulating conductor is inserted through a first radially extending hole and a second radially extending hole. B31. A hole extending in the longitudinal direction is a blind hole, according to any one of the methods in clauses B22 to B30. B32. Any one of the methods of clauses B22 to B31, further comprising the step of closing the opening of a longitudinally extending hole to close the opening. B33. If subject to clause B25, the connector is positioned before the termination of the blockage, in the manner of clause B32. B34. Screw such that the first conductor and the longitudinal conductors collectively form a conductive path. Multiple threaded fittings that engage to form a string, according to any of clauses B18-B21; One or more sensors positioned along the string and communicating with the conductive path. A string for a well, including the string itself. B35. The string of clause B34, wherein the conductive path is for transmitting power to one or more sensors and for transmitting signals from one or more sensors. B36. One or more sensors, Temperature sensor; Pressure sensor; accelerometer; Magnetometer; Ultrasonic sensor; Flow sensor; and / or Acoustic sensor A string in clause B34 or B35 that includes one or more of the following. B37. Any one of the strings from clauses B34 to B36, where the string is a casing string or a tubing string, and each tubular component is a casing or tubing component. C1. A string for a well, Multiple tubular components that engage with each other via a screw mechanism to form a string; One or more sensors arranged along the string, Includes, Each tubular component includes a longitudinally extending hole or groove for housing a conductor insulated from the tubular component, a first electrical contact at the first end of the tubular component, and a second electrical contact at the second end of the tubular component; Multiple tubular conductor components collectively form a conductive path; The sensor communicates with a conductive path. string. String of Clause C1, in which the conductive path transmits power to one or more sensors and transmits signals from one or more sensors. C3. One or more sensors are temperature sensors; pressure sensors; accelerometers; magnetometers; ultrasonic sensors; flow sensors; and / or acoustic sensors String of Clause C1 or C2, including one or more of the above. C4. String of any of Clauses C1 to C3, in which a longitudinally extending hole or groove is on the outer surface of each tubular component. C5. String of any of Clauses C1 to C4, in which one of the tubular components is a first tubular component and includes a pin having an outer surface with a male thread formed thereon at a first end, and the male thread is located between a first electrical contact and the end of the first tubular component. C6. String of any of Clauses C1 to C5, in which one of the tubular components is a second tubular component and includes a box having an inner surface with a female thread formed thereon at a second end, and a second electrical contact is located between the female thread and the end of the second tubular component. C(7). String of any of Clauses C1 to C6, in which the string is a casing string or a tubing string, and each tubular component is a casing or tubing tubular component.

Claims

1. A coupling for threaded joints, A tubular body having first and second ends, each end having a box having an inner surface thereon which female threads are formed for engagement with a pin of a tubular component; A first female electrical contact insulated from the tubular body, on the inner surface of the first end; A second female electrical contact insulated from the tubular body on the inner surface of the second end; and a longitudinal conductor insulated from the tubular body, communicating with the first and second female electrical contacts. Includes, The tubular body has a conductive hole formed therein, which includes a hole extending in the longitudinal direction, through which a longitudinal conductor extends. Coupling.

2. The first female electrical contact extends circumferentially around the inner surface; and / or The second female electrical contact extends circumferentially around the inner surface. The coupling according to claim 1.

3. The coupling according to claim 1 or 2, wherein the conductor is formed from a first wire and a second wire that are joined to each other at positions within a longitudinally extending hole using a connector within a longitudinally extending hole.

4. The connector is Solder sleeve; and / or Heat shrink tubing The coupling according to claim 3, including the coupling described in claim 3.

5. The coupling according to any one of the preceding claims, wherein each female electrical contact includes a deformable element deflected toward the inside of the box.

6. The coupling according to claim 5, wherein each deformable element is a coil spring extending in the circumferential direction.

7. A plurality of first female electrical contacts on the inner surface of the first end, each insulated from the tubular body, having a second circumferential length and spaced apart from each other by a second circumferential gap; and A plurality of second female electrical contacts, each insulated from the tubular body, on the inner surface of the end of the second terminal, having a third circumferential length and spaced apart from each other by a third circumferential gap. Further including, The coupling according to any one of the preceding claims.

8. The coupling according to any one of the preceding claims, wherein each female electrical contact is insulated from the tubular body by an elastomer seal, and the female electrical contact and conductor are embedded in the seal and partially exposed to form the female electrical contact.

9. The coupling according to any one of the preceding claims, wherein the conductor hole further includes, at the first end, a first radially extending hole extending from a first female electrical contact to a longitudinally extending hole, and at the second end, a second radially extending hole extending from a second female electrical contact to a longitudinally extending hole.

10. The coupling according to claim 9, wherein the longitudinally extending hole has a blind hole with an opening at the first end of the tubular body.

11. The coupling according to claim 10, wherein the opening of a longitudinally extending hole is closed using a plug.

12. The coupling according to any one of the preceding claims, wherein the longitudinal conductor extends only along the conductor hole from the first female electrical contact to the second female electrical contact.

13. The coupling according to any one of the preceding claims, wherein the longitudinal conductor is spaced apart from the outer surface and / or inner surface of the coupling along its entire length.

14. The coupling according to any one of claims 1 to 13, wherein the total length of the coupling in the axial direction is 20 inches or less, preferably 12 inches or less.

15. The coupling according to any one of the preceding claims, wherein the axial length of the coupling is 5 inches or more, preferably 7 inches or more.

16. It is a threaded joint, The coupling described in any one of the preceding claims; A first tubular component and a second tubular component, wherein each tubular component is A pin having an outer surface on which male threads are formed in a first terminal region, wherein each male thread is arranged to engage with a female thread of a coupling in an assembled configuration; The second terminal region on the opposite side; A male electrical contact insulated from the tubular component, on the outer surface of the first end region of the tubular component; and A first conductor extending along the tubular component, communicating with the male electrical contact, and insulated from the tubular component. A first tubular component and a second tubular component, including The male and female electrical contacts are arranged in the assembly configuration so as to be in contact with each other. Screw fittings.

17. The screw fitting according to claim 16, wherein each male electrical contact extends circumferentially around the outer surface.

18. When dependent on claim 7, each tubular component is A plurality of male electrical contacts on the outer surface of the first end region of a tubular component, each insulated from the tubular component, having a first circumferential length and spaced apart from each other by a first circumferential gap; It further includes, The first circumferential length is smaller than the second circumferential gap and the third circumferential gap; The second circumferential length and the third circumferential length are smaller than the first circumferential gap. The threaded joint according to claim 16 or 17.

19. A method for manufacturing a coupling for screw joints, A tubular body having first and second ends, each end having a box having an inner surface thereon which a female thread is formed for engaging with a pin of a tubular component; A hole extending in the longitudinal direction is machined through a tubular body; An insulated conductor is inserted into a hole extending in the longitudinal direction, forming a first female electrical contact and a second female electrical contact. The communication is to be performed such that the first female electrical contact is located on the inner surface of the first end and is insulated from the tubular body, and the second female electrical contact is located on the inner surface of the second end and is insulated from the tubular body. Methods that include...

20. The first female electrical contact extends circumferentially around the inner surface; and / or The second female electrical contact extends circumferentially around the inner surface. The method according to claim 19.

21. The insulating conductor includes a first wire and a second wire, and the insulating conductor is inserted into a hole extending in the longitudinal direction. Inserting the first wire into a hole extending longitudinally from the first end of the tubular body; The method according to claim 19 or 20, comprising inserting the second wire into a hole extending longitudinally from the second end of the tubular body so that the first and second wires are electrically connected.

22. A step of placing a connector in a hole extending in the longitudinal direction, wherein the step of inserting a first wire includes inserting the first wire into the connector, and the step of inserting a second wire includes inserting the second wire into the connector; A step of heating the tubular body to activate the connector and connecting the first wire to the second wire, The method according to claim 21, further comprising:

23. The connector is Solder sleeve, and / or Heat shrink tubing The method according to claim 22, including the method described in claim 22.

24. The method according to any one of claims 21 to 23, wherein the first female electrical contact is fixed to the first wire before the first wire is inserted.

25. The method according to any one of claims 21 to 24, wherein the second female electrical contact is fixed to the second wire before the second wire is inserted.

26. A process of machining a first radially extending hole at the first end down to a longitudinally extending hole; The process further includes machining a second radially extending hole at the second end down to a longitudinally extending hole, An insulating conductor is inserted through a first radially extending hole and a second radially extending hole. The method according to any one of claims 19 to 25.

27. The method according to any one of claims 19 to 26, wherein the longitudinally extending hole has a blind hole.

28. The method according to any one of claims 19 to 27, further comprising the step of closing the opening of a hole that extends in the longitudinal direction.

29. The method according to claim 28, wherein the connector is positioned before the end is closed.

30. A plurality of threaded joints according to any one of claims 16 to 18, wherein the first and second conductors are screw-engaged to form a string such that they collectively form a conductive path; One or more sensors positioned along the string and communicating with a conductive path. Strings for wells, including those used in wells.

31. The string according to claim 30, wherein the conductive path is for transmitting power to one or more sensors and for transmitting signals from one or more sensors.

32. One or more sensors, Temperature sensor; Pressure sensor; Accelerometer; Magnetometer; Ultrasonic sensor; Flow sensor; and / or Acoustic sensor The string according to claim 30 or 31, comprising one or more of the following.

33. The string according to any one of claims 30 to 32, wherein the string is a casing string or a tubing string, and each tubular component is a casing or a tubular component.

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