Threaded connections for exploration and production of hydrocarbon wells

Abstract

A threaded connection for exploration and production in a hydrocarbon well includes a connecting member, a first tubular member, and a second tubular member, wherein the connecting member has a connecting outer diameter, a first sleeve portion having a first internal thread, and a second sleeve portion having a second internal thread; the first tubular member has a first unthreaded tube portion and a first pin portion having a first external thread; the second tubular member has a second unthreaded tube portion and a second pin portion having a second external thread; the first internal thread and the first external thread are configured to form a first internal main seal upon final engagement; and the second internal thread and the second external thread are configured to form a second internal main seal upon final engagement.

Description

[0001] Priority requirements

[0002] This application claims priority to U.S. Patent Application No. 62 / 873,594, filed July 12, 2019, and Dutch Patent Application No. N2023800, filed September 10, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to a threaded connection for exploration and production in hydrocarbon wells, comprising a connecting member, a first tubular member, and a second tubular member. Such a threaded connection, including a connecting member for end-to-end connection of the first and second tubular members, is also referred to as a "threaded connection".

[0004] In a known threaded connection, the connecting member has a connecting outer diameter COD, a first sleeve portion with a first internal thread, and a second sleeve portion with a second internal thread. The first sleeve portion and the second sleeve portion have a radial sleeve portion thickness A located between the first internal thread and the second internal thread. A first tubular member has a first unthreaded tube portion and a first pin portion with a first external thread. A second tubular member has a second unthreaded tube portion and a second pin portion with a second external thread. The first unthreaded tube portion and the second unthreaded tube portion have a tube outer diameter TOD and a radial tube wall thickness W. The connecting outer diameter COD is greater than the tube outer diameter TOD. The first internal thread, the second internal thread, the first external thread, and the second external thread have dovetail wedge threads. The first internal thread and the first external thread are configured to form a first internal main seal upon final engagement. The second internal thread and the second external thread are configured to form a second internal main seal upon final engagement.

[0005] The first and second inner main seals form the first line of defense against internal pressure in the threaded connection when finally snapped together. Background Technology

[0006] In some cases, known threaded connections have too large an outer diameter to be used for exploration and / or production of specific smaller diameter hydrocarbon wells, such as so-called slender profile hydrocarbon wells, sometimes also referred to as small boreholes or small borehole completions. Summary of the Invention

[0007] The object of this invention is to provide an improved or at least alternative threaded connection that can be used in the specific smaller diameter hydrocarbon wells.

[0008] This objective is achieved through a threaded connection used for exploration and production in hydrocarbon wells, and includes;

[0009] - A connecting member having a connecting outer diameter COD and including

[0010] The first sleeve portion includes a first internal thread.

[0011] The second sleeve portion includes a second internal thread, and

[0012] The edge portion includes a radially extending inner edge, wherein

[0013] The edge portion is located between the first sleeve portion and the second sleeve portion and has a radial edge portion thickness B and an axial edge portion length C, and

[0014] The first sleeve portion and the second sleeve portion have radial sleeve portion thicknesses A located between the inner edge and the first internal thread and the second internal thread, respectively.

[0015] - A first tubular member, comprising a first unthreaded tubular portion and a first pin portion including a first external thread, and

[0016] - A second tubular member, comprising a second unthreaded tubular portion and a second pin portion including a second external thread, wherein

[0017] --The first and second unthreaded tube sections have an outer diameter TOD and a radial wall thickness W.

[0018] --The first tubular member and the second tubular member have an inner diameter TID.

[0019] --The first internal thread, the second internal thread, the first external thread, and the second external thread have dovetail wedge-shaped threads.

[0020] --The first internal thread and the first external thread are configured to form a first internal main seal upon final engagement.

[0021] --The second internal thread and the second external thread are configured to form a second internal main seal upon final engagement, and

[0022] --Threaded connection is compatible;

[0023] COD>TOD

[0024] B = approximately ((COD – TID) / 2)

[0025] C>0, and

[0026] A <W。

[0027] COD>TOD indicates that the outer diameter COD of the connecting member is greater than the outer diameter TOD of the first unthreaded tube section of the first tubular member and the second unthreaded tube section of the second tubular member.

[0028] When compared to known screw connections, an edge portion is added between the first sleeve portion and the second sleeve portion. The edge portion thickness B of the edge portion is measured in the radial direction relative to the longitudinal axis of the screw connection, and the edge portion length C is measured in the axial direction.

[0029] B = (COD–TID) / 2 means that the edge portion extends from the connection outer diameter COD of the connection member all the way to the tube inner diameter TID of the first and second tubular members. This is beneficial for fluid to flow through the screw connection. B being a value of "about" (COD–TID) / 2 means that the extent to which B may differ from the value of (COD–TID) / 2 is such that this difference does not interfere with the function of the edge and the operation of the connection. For example, the difference may be the result of machine tolerances.

[0030] C>0 means that an edge portion with an axial edge portion length of C has been added to the screw connection.

[0031] A screw connection according to the present invention including a connection member for end-to-end connection of first and second tubular members is also referred to as a "thread and connection" connection.

[0032] When the internal pressure of the fluid flowing through the screw connection is too high and separates the first internal thread from the first external thread and the second internal thread from the second external thread, the operation of the first and second internal main seals is impaired.

[0033] To withstand these high internal pressures, the connection member of a known screw connection has a relatively large radial sleeve portion thickness A measured between the first internal thread and the second internal thread of the connection member. In a known screw connection, the radial sleeve portion thickness A is greater than the radial wall thickness W of the first non-threaded tube portion of the first tubular member and the second non-threaded tube portion of the second tubular member. This results in a relatively large connection outer diameter.

[0034] The separation of the first internal thread from the first external thread and the second internal thread from the second external thread is caused by radial deformation generated by the internal pressure of the fluid flowing through the screw connection. The present invention is based on the insight that the radial deformation is associated with hoop stress in the screw connection, and these hoop stresses can be reduced by adding the edge portion of the screw connection according to the present invention.

[0035] This means that by adding an edge portion to a known screw connection, the radial sleeve portion thickness A of the connection member can be reduced while ensuring that the first internal main seal between the first internal thread and the first external thread and the second internal main seal between the second internal thread and the second external thread are maintained. As a result, the radial sleeve portion thickness A of the first and second sleeve portions of the connection member of the screw connection according to the present invention is less than the radial wall thickness W of the first and second non-threaded tube portions of the first and second tubular members. This is represented by A < W.

[0036] The reduced radial sleeve thickness A can be achieved by removing material from the outer connecting surface of the connecting member while maintaining the first and second internal threads of both the connecting member and the tubular member. Thus, even with standardized tubular members, the outer diameter COD of the connection is reduced, and the threaded connection can be used in the specific smaller hydrocarbon wells.

[0037] In one embodiment of the threaded connection, the axial edge length C of the edge portion conforms to the following: C≤31.75 mm (1.25 inch), preferably C≤27.94 mm (1.1 inch), more preferably C≤25.4 mm (1.0 inch).

[0038] In one embodiment of the threaded connection, the axial edge length C of the edge portion conforms to: C ≥ 6.35 mm (0.25 inches), preferably C ≥ 10.16 mm (0.4 inches), more preferably C ≥ 12.7 mm (0.5 inches).

[0039] In one embodiment of the threaded connection, the axial edge length C of the edge portion conforms to: 20.32 mm (0.8 inch) ≤ C ≤ 27.94 mm (1.1 inch), preferably C = 25.4 mm (1.0 inch).

[0040] In one embodiment of the threaded connection, the threaded connection conforms to the following: A ≤ 0.9W, preferably A ≤ 0.8W. This indicates that the radial sleeve thickness A is less than or equal to 90% of the radial tube wall thickness W, preferably less than or equal to 80% of the radial tube wall thickness W.

[0041] In one embodiment of the threaded connection, the threaded connection conforms to;

[0042] A ≥ 0.7W. This indicates that the radial sleeve thickness A is greater than or equal to 70% of the radial pipe wall thickness W.

[0043] In one embodiment of the threaded connection, the radial sleeve thickness A is located at the critical cross-section of the first sleeve portion and the second sleeve portion. In another embodiment of the threaded connection, the outer diameters (TOD) of the first and second unthreaded tube portions of the first and second tubular members conform to: 114.3 mm (4.5 inches) ≤ TOD ≤ 244.5 mm (9 5 / 8 inches), preferably, 114.3 mm (4.5 inches) ≤ TOD ≤ 193.7 mm (7.625 inches), more preferably, 114.3 mm (4.5 inches) ≤ TOD ≤ 139.7 mm (5.5 inches).

[0044] In one embodiment of the threaded connection, the radial wall thickness W of the first and second unthreaded sections of the first and second tubular members conforms to: 6.3 mm (0.250 inch) ≤ W ≤ 12.7 mm (0.500 inch), preferably 7.3 mm (0.290 inch) ≤ W ≤ 11.1 mm (0.437 inch).

[0045] In one embodiment of the threaded connection, the threaded connection includes the following features: in a first direction from the inner edge and toward the first inner main seal, the first internal thread and the first external thread begin to fully contact at the first seal initiation position; in the opposite second direction from the inner edge and toward the second inner main seal, the second internal thread and the second external thread begin to fully contact at the second seal initiation position, the first seal initiation position being located at an axial sealing distance D from the second seal initiation position, and D>C.

[0046] In one embodiment of the threaded connection, the threaded connection conforms to:

[0047] 3.6 mm (0.142 in) ≤ (D–C) / 2 ≤ 9.9 mm (0.392 in). This indicates that the first and second seal initiation positions are located at an axial distance of greater than or equal to 3.6 mm (0.142 in) and less than or equal to 9.9 mm (0.392 in) from the edge. Preferably, the threaded connection conforms to: 5 mm (0.2 in) ≤ (D–C) / 2 ≤ 7.7 mm (0.3 in), more preferably (D–C) / 2 is 6.1 mm (0.242 in).

[0048] In one embodiment of the threaded connection, the radially extending inner edge is located between the first pin and the second pin.

[0049] In an embodiment of the threaded connection, the first tubular member (more specifically, the first pin portion) includes a first pin head, the second tubular member (more specifically, the second pin portion) includes a second pin head, and the first and second pin heads are located at a distance from the inner edge when finally fastened.

[0050] In one embodiment of the threaded connection, the radially extending inner edge is located between the first pin and the second pin.

[0051] In one embodiment of the threaded connection, the threaded connection does not have any further internal sealing (other than the first and second internal main seals) upon final threading.

[0052] In one embodiment of the threaded connection, the threaded connection is not subject to any further secondary seals or metal-to-metal seals upon final engagement (other than the engagement of the first inner main seal, the second inner main seal, and the complete thread).

[0053] In one embodiment of the threaded connection, the first internal thread and the first external thread together form a first thread step, and the second internal thread and the second external thread together form a second thread step.

[0054] In one embodiment of the threaded connection, the threaded connection has no further threaded steps (except for the first threaded step and the second threaded step). Both the first threaded step and the second threaded step are single threaded steps.

[0055] In one embodiment of the threaded connection, the first thread step and the second thread step are tapered thread steps.

[0056] In one embodiment of a threaded connection:

[0057] - Threaded connections define the longitudinal axis.

[0058] - The first internal thread has a constant first internal thread taper angle α1 relative to the longitudinal axis.

[0059] - The first external thread has a constant first external thread taper angle β1 relative to the longitudinal axis.

[0060] - The first internal thread taper angle α1 and the first external thread taper angle β1 are equal to each other.

[0061] - The second internal thread has a constant second internal thread taper angle α2 relative to the longitudinal axis.

[0062] - The second external thread has a constant second external thread taper angle β2 relative to the longitudinal axis, and

[0063] - The second internal thread taper angle α2 and the second external thread taper angle β2 are equal to each other.

[0064] In one embodiment of the threaded connection, the first internal thread taper angle α1, the first external thread taper angle β1, the second internal thread taper angle α2, and the second external thread taper angle β2 have a diameter taper between and including 0.36 mm / revolution and 0.86 mm / revolution (0.014 inch / revolution and 0.034 inch / revolution), preferably between and including 0.51 mm / revolution and 0.71 mm / revolution (0.020 inch / revolution and 0.028 inch / revolution).

[0065] In one embodiment of the threaded connection, the first internal thread and the first external thread are configured to have a first radial thread interference upon final engagement, and the second internal thread and the second external thread are configured to have a second radial thread interference upon final engagement.

[0066] In one embodiment of a threaded connection:

[0067] - Threaded connections define the longitudinal axis.

[0068] - The first internal thread has a constant first internal thread taper angle α1 relative to the longitudinal axis.

[0069] - The first external thread has a constant first external thread taper angle β1 relative to the longitudinal axis.

[0070] -The cone angle α1 of the first internal thread is greater than the cone angle β1 of the first external thread.

[0071] - The second internal thread has a constant second internal thread taper angle α2 relative to the longitudinal axis.

[0072] - The second external thread has a constant second external thread taper angle β2 relative to the longitudinal axis, and

[0073] - The taper angle α2 of the second internal thread is greater than the taper angle β2 of the second external thread.

[0074] In one embodiment of the threaded connection, the first internal thread taper angle α1 and the second internal thread taper angle α2 have an internal taper diameter between and including 0.41 mm / revolution and 0.91 mm / revolution (0.016 inch / revolution and 0.036 inch / revolution), preferably between and including 0.56 mm / revolution and 0.76 mm / revolution (0.022 inch / revolution and 0.030 inch / revolution). The first external thread taper angle β1 and the second external thread taper angle β2 have a diameter external taper between 0.36 mm / revolution and 0.86 mm / revolution (0.014 inch / revolution and 0.034 inch / revolution) and include the range of 0.36 mm / revolution and 0.86 mm / revolution (0.014 inch / revolution and 0.034 inch / revolution), preferably between 0.51 mm / revolution and 0.71 mm / revolution (0.020 inch / revolution and 0.028 inch / revolution) and include the range of 0.51 mm / revolution and 0.71 mm / revolution (0.020 inch / revolution and 0.028 inch / revolution).

[0075] In one embodiment of a threaded connection:

[0076] - The first internal thread and the first external thread are configured to have a first radial thread interference upon final engagement.

[0077] -The interference of the first radial thread between the first internal thread and the first external thread decreases in a first direction from the inner edge and toward the first inner main seal.

[0078] - The second internal thread and the second external thread are configured to have a second radial thread interference upon final engagement, and

[0079] - The interference of the second radial thread between the second internal thread and the second external thread decreases in the opposite direction from the inner edge and toward the second inner main seal.

[0080] The phrase "from the inner edge and toward the first inner main seal" indicates the direction of the first direction. It does not mean that the first direction begins at the inner edge and / or ends at the first inner main seal. Similarly, the phrase "from the inner edge and toward the second inner main seal" indicates the direction of the second direction. It does not mean that the second direction begins at the inner edge and / or ends at the second inner main seal.

[0081] In one embodiment of a threaded connection:

[0082] - The first radial thread interference between the first internal thread and the first external thread decreases in the first direction until it reaches a first radial thread interference value of zero, and

[0083] - The interference of the second radial thread between the second internal thread and the second external thread decreases in the second direction until it reaches a zero value.

[0084] In one embodiment of a threaded connection:

[0085] - The first internal thread and the first external thread in the first direction and beyond the first thread position have no first radial thread clearance between the first internal thread and the first external thread, and the first radial thread interference value reaches zero at the first thread position, and

[0086] - The second internal thread and the second external thread are in the second direction and beyond the second thread position without a second radial thread clearance between the second internal thread and the second external thread, and the second radial thread interference value reaches zero at the second thread position.

[0087] In one embodiment of a threaded connection:

[0088] - A first internal thread and a first external thread have a first radial thread clearance between the first internal thread and the first external thread in a first direction and beyond the first thread position, reaching a first radial thread interference value of zero at the first thread position, and

[0089] - The second internal thread and the second external thread have a second radial thread clearance between the second internal thread and the second external thread in the second direction and beyond the second thread position, and the second radial thread interference value reaches zero at the second thread position.

[0090] In one embodiment of the threaded connection, the connecting member includes a first release groove located between a first internal thread and an inner edge, and a second release groove located between a second internal thread and an inner edge. More specifically, the first release groove is located between the first internal thread and the inner edge in an axial direction along the longitudinal axis, and the second release groove is located between the second internal thread and the inner edge in an axial direction along the longitudinal axis. During the manufacturing process of the connecting member, the lathe tool uses the first and second release grooves to remove and withdraw the connecting member from the first and second internal threads without damaging the radially extending inner edge after the formation of the first and second internal threads.

[0091] In one embodiment of the threaded connection, the radial sleeve portion thickness A of the first sleeve portion and the second sleeve portion is located at the first release groove and the second release groove, respectively.

[0092] In one embodiment of the threaded connection, the outer diameter COD is the maximum diameter dimension of the threaded connection.

[0093] In one embodiment of the threaded connection, the edge portion has an inner edge diameter RID, and the threaded connection conforms; RID = approximately TID. This indicates that the edge portion, more specifically the inner edge, is flush with or nearly flush with the first and second tubular members. The value of RID being approximately TID indicates the degree to which the difference between RID and TID is such that the difference does not interfere with the function of the edge and the role of the connection. For example, the difference between TID and RID may be a result of machine tolerances. In a preferred embodiment, RID = TID ± 0.127 mm (0.050 inch). In a more preferred embodiment, RID = TID.

[0094] In one embodiment of the threaded connection, the edge portion has an outer edge diameter ROD and the threaded connection conforms to: B = (ROD - RID) / 2. This indicates that the radial edge thickness B extends from the outer edge diameter ROD all the way to the inner edge diameter RID.

[0095] In one embodiment of the threaded connection, the threaded connection conforms to COD = ROD. This indicates that the outer diameter COD of the connection and the outer diameter ROD of the edge are equal to each other.

[0096] In one embodiment of the threaded connection, the first sleeve portion has a first sleeve outer diameter FBOD, the second sleeve portion has a second sleeve outer diameter SBOD, and the threaded connection conforms to: COD = FBOD = SBOD. This indicates that the connection outer diameter COD, the first sleeve outer diameter FBOD, and the second sleeve outer diameter SBOD are equal to each other.

[0097] In one embodiment of the threaded connection, the threaded connection defines a longitudinal axis.

[0098] In one embodiment of the threaded connection, the radial sleeve portion thickness A of the first sleeve portion and the second sleeve portion is located between the inner edge and the first internal thread and the second internal thread, respectively, in the axial direction along the longitudinal axis.

[0099] In one embodiment of the threaded connection, the radial sleeve portion thickness A of the first sleeve portion and the second sleeve portion is measured in the radial direction relative to the longitudinal axis.

[0100] In one embodiment of the threaded connection, the connecting member includes an outer connecting surface that defines a connecting outer diameter COD, and the radial sleeve portion thickness A of the first sleeve portion and the second sleeve portion is measured from the outer connecting surface.

[0101] In one embodiment of the threaded connection, the outer connecting surface forms the outer thickness boundary of the radial sleeve portion thickness A of the first sleeve portion and the second sleeve portion.

[0102] In one embodiment of the threaded connection, a first pin of the first tubular member is located between the inner edge and the first unthreaded tubular portion in the axial direction along the longitudinal axis, and a second pin of the second tubular member is located between the inner edge and the second unthreaded tubular portion in the axial direction along the longitudinal axis.

[0103] In one embodiment of the threaded connection, the edge portion and the inner edge completely surround the longitudinal axis.

[0104] In one embodiment of the threaded connection, the edge portion includes an inner edge surface that is nearly flush with, preferably flush with, the first inner surface of the first tubular member and the second inner surface of the second tubular member.

[0105] Those skilled in the art will understand that the threaded connection according to the present invention may include any combination of features in the embodiments defined above for the threaded connection. Attached Figure Description

[0106] Embodiments of the threaded connection according to the present invention will be described by way of example only, wherein reference is made to the accompanying drawings, in which corresponding reference numerals denote corresponding parts, and wherein:

[0107] Figure 1A A perspective view schematically illustrating one embodiment of the threaded connection according to the present invention is shown.

[0108] Figure 1B schematically shown Figure 1A Cross-sectional view of the threaded connection.

[0109] Figure 2schematically shown Figure 1A An enlarged view of part II.

[0110] Figure 3 schematically shown Figure 2 A magnified view of part III.

[0111] Figure 4 Including graph 1, which shows the curves with Figure 1A The different embodiments of the threaded connection (bn) and the circumferential stress in the threaded connection (a) without an edge portion,

[0112] Figure 5 Containment curve Figure 2 It shows the circumferential stress at the first sealing initiation position of the threaded connection (an) in Figure 1.

[0113] Figure 6 Containment curve Figure 3 It shows the curve Figure 2 The circumferential stress at the first sealing initiation position of the alternative embodiment of the threaded connection a'-n'

[0114] Figure 7 schematically shown Figure 1A The representation of the taper angle of a threaded connection.

[0115] Figure 8 The diagram schematically illustrates the representation of the taper angle of a first alternative embodiment of the threaded connection according to the invention, and...

[0116] Figure 9 The diagram schematically illustrates the representation of the taper angle in a second alternative embodiment of the threaded connection according to the invention. Detailed Implementation

[0117] Figure 1A A perspective view of an embodiment of the threaded connection 1 according to the invention is shown when finally fastened 20. The threaded connection 1 for exploration and production in hydrocarbon wells includes a connecting member 2, a first tubular member 9, and a second tubular member 13. Parts of the connecting member 2, the first tubular member 9, and the second tubular member 13 are cut open to show more details of the threaded connection 1. Figure 1B It shows Figure 1A A cross-sectional view of a threaded connection. Figure 2 Showing Figure 1A A magnified view of part II. Figure 3 Showing Figure 2 A magnified view of part III.

[0118] The threaded connection 1 defines a longitudinal axis 31. The connecting member 2 has a connecting outer diameter COD defined by an outer connecting surface 35, a first sleeve portion 3 including a first internal thread 4, a second sleeve portion 5 including a second internal thread 6, and an edge portion 7 including a radially extending inner edge 8. The first sleeve portion 3 has a first sleeve length FBL. The second sleeve portion 5 has a second sleeve length SBL. The edge portion 7 is located between the first sleeve portion 3 and the second sleeve portion 5, and has a radial edge portion thickness B and an axial edge portion length C. The first sleeve portion 3 and the second sleeve portion 5 have radial sleeve portion thicknesses A, which are located between the inner edge 8 and the first internal thread 4 and the second internal thread 6, respectively. This means that both the first sleeve portion 3 and the second sleeve portion 5 have radial sleeve portion thicknesses A. The radial sleeve portion thickness A of the first sleeve portion 3 is located between the first internal thread 4 and the inner edge 8. The radial sleeve portion thickness A of the second sleeve portion 5 is located between the second internal thread 6 and the inner edge 8.

[0119] More specifically, the radial sleeve portion thickness A of the first sleeve portion 3 and the second sleeve portion 5 is located between the inner edge 8 and the first internal thread 4 and the second internal thread 6, respectively, in the axial direction along the longitudinal axis 31. The radial sleeve portion thickness A of the first sleeve portion 3 and the second sleeve portion 5 is measured in the radial direction relative to the longitudinal axis 31. The radial sleeve portion thickness A of the first sleeve portion 3 and the second sleeve portion 5 is measured starting from the outer connecting surface 35. The outer connecting surface 35 forms the outer thickness boundary 36 of the radial sleeve portion thickness A of the first sleeve portion 3 and the second sleeve portion 5.

[0120] Specifically, it is noted that the connecting member 2, including the edge portion 7 with the inner edge 8, rotates about the longitudinal axis 31. Therefore, the edge portion 7, including the inner edge 8, is located at an axial distance from the first internal thread 4 and the second internal thread 6. Consequently, the radial sleeve portion thickness A of the first sleeve portion 3 and the second sleeve portion 5 is located between the inner edge 8 and the first internal thread 4 and the second internal thread 6.

[0121] The first tubular member 9 includes a first unthreaded tube portion 10 and a first pin portion 11 including a first external thread 12.

[0122] The second tubular member 13 includes a second unthreaded tube portion 14 and a second pin portion 15 including a second external thread 16.

[0123] The first pin 11 of the first tubular member 9 is located between the inner edge 8 and the first unthreaded tube 10 in the axial direction along the longitudinal axis 31, and the second pin 15 of the second tubular member 13 is located between the inner edge 8 and the second unthreaded tube 14 in the axial direction along the longitudinal axis 31.

[0124] The first unthreaded tube section 10 and the second unthreaded tube section 14 have an outer diameter TOD and a radial wall thickness W.

[0125] The first tubular member 9 and the second tubular member 13 have an inner diameter TID.

[0126] The first internal thread 4, the second internal thread 6, the first external thread 12, and the second external thread 16 have dovetail wedge threads 17.

[0127] The dovetail wedge thread 17 is characterized by having negative flank angles for its engagement and carrying flanks. The width of the dovetail wedge thread 17 increases in opposite directions at the pin and corresponding sleeve portions. The rate of change of width of the dovetail wedge thread 17 is defined by a variable commonly referred to as the "wedge ratio." The wedge ratio (though technically not a ratio) refers to the difference between the lead on the engagement flank and the lead on the carrying flank, which causes the width of the dovetail wedge thread 17 to vary along the threaded connection. The "lead" of a thread refers to the difference in distance between the components of a thread on a continuous thread. Therefore, the "engagement lead" is the distance along the axial length of the threaded tubular connection between the engagement flanks of a continuous pitch.

[0128] The first internal thread 4 and the first external thread 12 are configured to form a first internal main seal 19 upon final engagement 20. The second internal thread 6 and the second external thread 16 are configured to form a second internal main seal 18 upon final engagement 20.

[0129] The term "locking" refers to engaging the first and second pins 11, 15 into the first and second sleeve portions 3, 5 and threading the parts together by applying torque. Final locking 20 refers to the following: locking is completed by threading the first and second pins 11, 15 and the first and second sleeve portions 3, 5 together until the required torque is achieved, or until the first and second pins 11, 15 reach a specific position relative to the first and second sleeve portions 3, 5.

[0130] The first inner main seal 19 is formed by complete contact between the first inner thread 4 and the first outer thread 12, and the second inner main seal 18 is formed by complete contact between the second inner thread 6 and the second outer thread 16.

[0131] The first and second inner main seals 18 and 19 form the first line of defense against internal pressure in the threaded connection 1 when the final snap 20 is engaged.

[0132] Threaded connection 1 is acceptable;

[0133] COD>TOD

[0134] B = (COD – TID) / 2

[0135] C>0, and

[0136] A <W。

[0137] COD>TOD indicates that the outer diameter COD of the connecting member 2 is greater than the outer diameter TOD of the first unthreaded pipe section 10 and the second unthreaded pipe section 14.

[0138] Compared to known threaded connections, an edge portion 7 is added between the first sleeve portion 3 and the second sleeve portion 5. The edge portion 7 has the same external dimensions as the first and second sleeve portions 3 and 5, and has an inner edge 8 extending radially inward toward the longitudinal axis 31 and located between the first pin portion 11 of the first tubular member 9 and the second pin portion 15 of the second tubular member 13. The edge portion 7 completely surrounds the longitudinal axis 31 and has an edge thickness B measured radially and an edge length C measured axially. The inner edge 8 is a circumferential edge surrounding the longitudinal axis 31.

[0139] B = (COD – TID) / 2 indicates that the inner edge 8 extends from the outer diameter COD of the connecting member to the inner diameter TID of the pipe. This facilitates fluid flow through the threaded connection 1.

[0140] The edge portion 7 includes an inner edge surface 34, which is flush with the first inner surface 32 of the first tubular member 9 and the second inner surface 33 of the second tubular member 13.

[0141] C>0 indicates that an edge portion 7 with an axial edge length C has been added to the threaded connection.

[0142] The axial edge length C may be: C≤31.75 mm (1.25 inch), preferably C≤27.94 mm (1.1 inch), more preferably C≤25.4 mm (1.0 inch).

[0143] The axial edge length C may be: C ≥ 6.35 mm (0.25 inches), preferably C ≥ 10.16 mm (0.4 inches), more preferably C ≥ 12.7 mm (0.5 inches).

[0144] The axial edge length C can conform to the following: 20.32 mm (0.8 inch) ≤ C ≤ 27.94 mm (1.1 inch), preferably C = 25.4 mm (1.0 inch).

[0145] A < W indicates that the radial sleeve thickness A of the first and second sleeve portions 3 and 5 is less than the radial tube wall thickness W of the first and second unthreaded tube portions 10 and 14 of the first and second tubular members 9 and 13.

[0146] To withstand high internal pressures, known threaded connections typically have a radial sleeve thickness A greater than the radial tube thickness W. This results in a large connection outer diameter COD.

[0147] The edge portion 7 of the threaded connection 1 according to the invention allows for a reduction in the radial sleeve thickness A, while ensuring that the first and second inner main seals 18, 19 are maintained under high internal pressure. As a result, a threaded connection 1 with a smaller outer diameter COD can be provided, thereby enabling the threaded connection 1 to be used in smaller diameter hydrocarbon wells, such as so-called elongated profile hydrocarbon wells, which are sometimes referred to as small boreholes or small borehole completions.

[0148] The maximum diameter of this type of threaded connection 1 is typically determined by the outer diameter (COD) of the connecting member 2. For this type of threaded connection 1 used in hydrocarbon well exploration and production, tubular members with standardized outer diameters (TOD) are typically used for the first and second tubular members 9 and 13. To reduce the maximum diameter of the threaded connection 1, it is necessary to reduce the thickness (A) of the radial sleeve portion of the connecting member 2.

[0149] The radial sleeve thickness A and the radial pipe wall thickness W can meet the following requirements: A≤0.9W, preferably A≤0.8W.

[0150] The radial sleeve thickness A and the radial pipe wall thickness W can meet the following requirements: A ≥ 0.7W.

[0151] The radial sleeve thickness A is located at the critical cross-section of the first sleeve portion 3 and the second sleeve portion 5.

[0152] The outer diameter (TOD) of the pipe may conform to: 114.3 mm (4.5 inches) ≤ TOD ≤ 244.5 mm (9 5 / 8 inches), preferably 114.3 mm (4.5 inches) ≤ TOD ≤ 193.7 mm (7.625 inches), and more preferably 114.3 mm (4.5 inches) ≤ TOD ≤ 139.7 mm (5.5 inches).

[0153] The radial wall thickness W can conform to: 6.3 mm (0.250 inch) ≤ W ≤ 12.7 mm (0.500 inch), preferably 7.3 mm (0.290 inch) ≤ W ≤ 11.1 mm (0.437 inch).

[0154] In a first direction 21, originating from the inner edge 8 and moving towards the first inner main seal 19, the first internal thread 4 and the first external thread 12 begin to fully contact at the first sealing start position 22. In a second direction 23, originating from the inner edge 8 and moving towards the second inner main seal 18, the second internal thread 6 and the second external thread 16 begin to fully contact at the second sealing start position 24. The first sealing start position 22 is located at an axial sealing distance D from the second sealing start position 24. The axial sealing distance D is greater than the axial edge length C. In other words, the axial sealing distance D and the axial edge length C satisfy: D > C.

[0155] The phrase "first direction 21 originating from inner edge 8 and toward first inner main seal 19" indicates the direction of the first direction 21. It does not indicate that the first direction 21 begins at inner edge 8 and / or ends at first inner main seal 19. Similarly, the phrase "second direction 23 originating from inner edge 8 and toward second inner main seal 18" indicates the direction of the second direction 23. It does not indicate that the second direction 23 begins at inner edge 8 and / or ends at second inner main seal 18.

[0156] The axial edge length C and the axial sealing distance D can conform to the following: 3.6 mm (0.142 inches) ≤ (D–C) / 2 ≤ 9.9 mm (0.392 inches), preferably 5 mm (0.2 inches) ≤ (D–C) / 2 ≤ 7.7 mm (0.3 inches), and more preferably (D–C) / 2 is 6.1 mm (0.242 inches).

[0157] The radially extending inner edge 8 is located between the first pin 11 and the second pin 15.

[0158] The first tubular member 9 (more specifically, the first pin 11) includes a first pin head 25, the second tubular member 13 (more specifically, the second pin 15) includes a second pin head 26, and when the final fastening 20 is completed, the first pin head 25 and the second pin head 26 are located at a certain distance from the inner edge 8 (see [link to product description]). Figure 3 ).

[0159] The radially extending inner edge 8 is located between the first pin 26 and the second pin 26.

[0160] When the final snap 20 is fastened, the threaded connection 1 has no further internal seals other than the first inner main seal 19 and the second inner main seal 18.

[0161] The first internal thread 4 and the first external thread 12 together form the first thread step 27. The second internal thread 6 and the second external thread 16 together form the second thread step 28. The threaded connection 1 has no other thread steps. This means that there are no other thread steps besides the first thread step 27 and the second thread step 28. The first thread step 27 and the second thread step 28 are tapered thread steps.

[0162] The connecting member 2 includes a first release groove 29 located between the first internal thread 4 and the inner edge 8, and a second release groove 30 located between the second internal thread 6 and the inner edge 8. More specifically, the first release groove 29 is located between the first internal thread 4 and the inner edge 8 in the axial direction along the longitudinal axis 31, and the second release groove 30 is located between the second internal thread 6 and the inner edge 8 in the axial direction along the longitudinal axis 31. The radial sleeve portion thickness A of the first sleeve portion 3 and the second sleeve portion 5 is located at the first release groove 29 and the second release groove 20, respectively.

[0163] In the illustrated embodiment, the edge portion 7 has an edge inner diameter RID equal to the inner diameter TID of the tube. In other words, the inner diameter TID and the edge inner diameter RID are identical; TID = RID. In other embodiments, there may be a difference between the inner diameter TID and the edge inner diameter RID, for example, on the order of ±0.127 mm (0.050 inches).

[0164] Edge portion 7 has an outer edge diameter ROD and a radial edge thickness B equal to the difference between the outer edge diameter ROD and the inner edge diameter RID divided by 2. In other words, the radial edge thickness B, the outer edge diameter ROD, and the inner edge diameter RID conform to the following: B = (ROD – RID) / 2.

[0165] The outer diameter of the joint (COD) is equal to the outer diameter of the edge (ROD). In other words, the outer diameter of the joint (COD) and the outer diameter of the edge (ROD) are equal; COD = ROD.

[0166] The first sleeve portion 3 has a first sleeve outer diameter FBOD, and the second sleeve portion 5 has a second sleeve outer diameter SBOD, both of which are equal to the connecting outer diameter COD. In other words, the connecting outer diameter COD, the first sleeve outer diameter FBOD, and the second sleeve outer diameter SBOD are in agreement; COD = FBOD = SBOD.

[0167] Figure 4 Including graph 1, which shows the curves with Figure 1A The different embodiments of the threaded connection (bn) and the circumferential stress in the threaded connection (a) without edge 7.

[0168] For all threaded connections, the outer diameter TOD is 139.7 mm (5.5 inches), the inner diameter TID is 121.3 mm (4.776 inches), the radial wall thickness W is 9.2 mm (0.361 inches), the connection outer diameter COD is 148.6 mm (5.852 inches), and the radial sleeve thickness A is 6.9 mm (0.271 inches).

[0169] Figure 1 shows the normalized length of the threaded connection under circumferential stress at an internal pressure of 555 bar (8050 PSI). The length of the threaded connection is normalized from 0 to 1. The normalized length includes the distance between the distal ends of the fully formed first thread and the distal ends of the fully formed second thread. The distal end of the fully formed thread is where the fully formed thread enters the incomplete thread. The proximal end of the fully formed thread is the end closest to the edge, while the distal end of the fully formed thread is the end furthest from the edge.

[0170] The vertical line an indicates the respective first and second sealing start positions 22 and 24 of the threaded connection an.

[0171] The threaded connection a is not part of the present invention because it does not have an edge portion 7 including a radially extending inner edge 8.

[0172] The threaded connection bn has the same construction as the threaded connection a, except that an edge portion 7, including a radially extending inner edge 8, is added between the first and second sleeve portions 3 and 5.

[0173] The difference between threaded connections bn lies in their different axial edge lengths C. The axial edge lengths C of threaded connections bn are shown in Table 1.

[0174] The radial edge thickness B of all threaded connections bn is 13.64 mm (0.537 inches).

[0175] Threaded connection Axial edge length C Circumferential stress at the first seal initiation position a 0.00 millimeters (0.00 inches) 5426.2 bar (78700 PSI) b 2.54 mm (0.10 inches) 5157.3 bar (74800 PSI) c 5.08 mm (0.20 inches) 4805.6 bar (69700 PSI) d 6.35 mm (0.25 inches) 4660.9 bar (67600 PSI) e 7.62 mm (0.30 inches) 4591.9 bar (66600 PSI) f 10.16 mm (0.40 inches) 4378.17 bar (63500 PSI) g 12.7 mm (0.50 inches) 4205.8 bar (61000 PSI) h 15.24 mm (0.60 inches) 4067.9 bar (59000 PSI) i 20.32 mm (0.80 inches) 3930.0 bar (57000 PSI) j 25.4 mm (1.0 inch) 3743.9 bar (54300 PSI) k 27.94 mm (1.10 inches) 3737.0 bar (54200 PSI) l 31.75 mm (1.25 inches) 3688.7 bar (53500 PSI) m 38.1 mm (1.50 inches) 3716.3 bar (53900 PSI) n 43.18 mm (1.70 inches) 3688.7 bar (53500 PSI)

[0176] Table 1

[0177] The different positions of the first and second sealing start positions 22 and 24, indicated by the vertical line an in graph 1, are caused by the different axial edge lengths C of the edge portion 7 of the threaded connection bn.

[0178] The edge portion 7 of threaded connection bn is added between the first and second sleeve portions 3 and 5 of threaded connection a. Compared with threaded connection a, the length (in the axial direction) of threaded connection bn is increased by an amount equal to the length C of its axial edge portion.

[0179] Figure 5 Containment curve Figure 2 It shows that in Figure 4 The circumferential stress at the first sealing start position 22 of the threaded connection (an). This circumferential stress is also shown in Table 1. Graph 1 shows that the circumferential stress at the second sealing start position 24 is the same as the circumferential stress at the first sealing start position 22.

[0180] If the radial deformation (and associated circumferential stress) at the first and second seal initiation positions 22, 24 is too high, the first and second inner main seals 18, 19 will be damaged due to the separation of the first internal thread 4 from the first external thread 12 at the first seal initiation position 22 and the separation of the second internal thread 6 from the second external thread 16 at the second seal initiation position 24. Once separation occurs at the first and second seal initiation positions 22, 24 due to radial deformation caused by internal pressure, the remaining portion of the first internal thread 4 will more easily separate from the remaining portion of the first external thread 12, and the remaining portion of the second internal thread 6 will more easily separate from the remaining portion of the second external thread 16.

[0181] Compare curves 1 and 2. Figure 2The threaded connection a (without edge 7) and threaded connection bn (with edge 7) in the diagram reveal that edge 7 reduces the circumferential stress in threaded connection bn.

[0182] The degree of circumferential stress at the first and second seal initiation positions 22, 24 is particularly relevant because excessive circumferential stress (and associated radial deformation) at these positions will damage the first and second inner main seals 18, 19. Outside the first and second seal initiation positions 22, 24, the circumferential stress (and associated radial deformation) is less relevant because the internal pressure does not exceed the first and second seal initiation positions 22, 24 when the first and second inner main seals 18, 19 are maintained. Higher circumferential stress beyond the first and second seal initiation positions 22, 24 can... Figure 8 and Figure 9 The alternative embodiment of the threaded connection according to the invention shown is reduced.

[0183] Curve 1 and Curve Figure 2 It was also shown that the axial edge length C affects the degree of reduction in circumferential stress in the threaded connection bn, particularly at their first and second sealing initiation positions 22, 24. Initially, as the axial edge length C increases, the reduction in circumferential stress at the first and second sealing initiation positions 22, 24 increases; however, as the axial edge length C increases further, this further reduction gradually disappears.

[0184] An excessively large axial edge length C has the following disadvantages: the total length of the connecting member 2 (the sum of the first sleeve length FBL of the first sleeve portion 3, the edge length C of the edge portion 7, and the second sleeve length SBL of the second sleeve portion 5) increases without providing any additional benefit in reducing circumferential stress at the first and second sealing initiation positions 22, 24. Furthermore, increasing the total length of the connection further increases material costs. Moreover, exceeding a certain total length may limit the use of certain field equipment for fastening the connection. An excessively small axial edge length C has the disadvantage of making the inner edge 8 prone to damage.

[0185] Figure 6 Containment curve Figure 3 It shows the curve Figure 2 The circumferential stress at the first sealing initiation position 22 of the alternative embodiment of the threaded connection an'-n'.

[0186] For all threaded connections a'-n', the outer diameter TOD is 114.3 mm (4.5 inches), the inner diameter TID is 99.6 mm (3.920 inches), the radial wall thickness W is 7.4 mm (0.290 inches), the connection outer diameter COD is 122 mm (4.803 inches), and the radial sleeve thickness A is 5.4 mm (0.213 inches).

[0187] Similarly, the threaded connection a' is not part of the present invention because it does not have an edge portion 7 including a radially extending inner edge 8.

[0188] Similarly, the threaded connections b'-n' differ from each other in that they have different axial edge lengths C. The axial edge lengths C of the threaded connections b'-n' are shown in Table 2. The radial edge thickness B of all threaded connections b'-n' is 11.2 mm (0.442 inches).

[0189] For an internal pressure of 555 bar (8050 PSI), the circumferential stress at the first sealing initiation position 22 of the threaded connection a'-n' is also listed in Table 2. The circumferential stress at the second sealing initiation position 24 is the same as the circumferential stress at the first sealing initiation position 22.

[0190]

[0191]

[0192] Table 2

[0193] In the curve of threaded connection a'-n' Figure 3 The figure shows the curves related to the threaded connection an in Figure 1 and the curve. Figure 2 The same effect described.

[0194] Figure 7 Showing Figure 1A The taper angle of the threaded connection 1 at the final engagement 20. Similar to... Figure 2 The view is used to provide the following representation: the first pin pitch diameter PPD1 of the first external thread 12 of the first pin portion 11, the first sleeve pitch diameter BPD1 of the first internal thread 4 of the first sleeve portion 3, the second pin pitch diameter PPD2 of the second external thread 16 of the second pin portion 15, and the second sleeve pitch diameter BPD2 of the second internal thread 6 of the second sleeve portion 5.

[0195] Line I shows the variation of the first pin diameter PPD1 along the longitudinal axis 31. Line II shows the variation of the first sleeve diameter BPD1 along the longitudinal axis 31. Line III shows the variation of the second pin diameter PPD2 along the longitudinal axis 31. Line IV shows the variation of the second sleeve diameter BPD2 along the longitudinal axis 31.

[0196] The first internal thread taper angle α1 is the angle between line I of the first pin diameter PPD1 and the longitudinal axis 31. The first external thread taper angle β1 is the angle between line II of the first sleeve diameter BPD1 and the longitudinal axis 31. The second internal thread taper angle α2 is the angle between line III of the second pin diameter PPD2 and the longitudinal axis 31. The second external thread taper angle β2 is the angle between line IV of the second sleeve diameter BPD2 and the longitudinal axis 31.

[0197] Figure 7 The diagram shows that the first internal thread 4 has a constant first internal thread taper angle α1 relative to the longitudinal axis 31. The first external thread 12 has a constant first external thread taper angle β1 relative to the longitudinal axis 31. The second internal thread 6 has a constant second internal thread taper angle α2 relative to the longitudinal axis 31. The second external thread 16 has a constant second external thread taper angle β2 relative to the longitudinal axis 31.

[0198] The first internal thread taper angle α1 and the first external thread taper angle β1 are equal to each other. The second internal thread taper angle α2 and the second external thread taper angle β2 are equal to each other.

[0199] The first internal thread 4 and the first external thread 12 have a first radial thread interference 37. The second internal thread 6 and the second external thread 16 have a second radial thread interference 38.

[0200] The diametrical taper of the first internal thread taper α1, the first external thread taper β1, the second internal thread taper α2, and the second external thread taper β2 is between and includes 0.36 mm / revolution and 0.86 mm / revolution (0.014 inch / revolution and 0.034 inch / revolution), preferably between and including 0.51 mm / revolution and 0.71 mm / revolution (0.020 inch / revolution and 0.028 inch / revolution).

[0201] To determine the first internal thread taper angle α1, a person can measure the diameter taper and pitch on the first sleeve portion 3. The diameter taper is the change in the first sleeve pitch diameter BPD1 of the first internal thread 4 for each revolution along the first internal thread 4, and the pitch is the axial displacement for each revolution along the first internal thread 4. The taper angle can then be calculated using the following formula:

[0202]

[0203] This applies in a similar manner to the first external thread taper angle β1, the second internal thread taper angle α2, and the second external thread taper angle β2.

[0204] Figure 8 The taper angle of a first alternative embodiment of the threaded connection 1 according to the present invention is shown. This first alternative embodiment is related to… Figure 7 The only difference between the threaded connections is that the first internal thread cone angle α1 is greater than the first external thread cone angle β1, and the second internal thread cone angle α2 is greater than the second external thread cone angle β2.

[0205] The inner taper of the diameter of the first internal thread taper angle α1 and the second internal thread taper angle α2 is between and includes 0.41 mm / revolution and 0.91 mm / revolution (0.016 inch / revolution and 0.036 inch / revolution), preferably between and including 0.56 mm / revolution and 0.76 mm / revolution (0.022 inch / revolution and 0.030 inch / revolution). Furthermore, the external taper of the first external thread taper angle β1 and the second external thread taper angle β2 is between and includes 0.36 mm / revolution and 0.86 mm / revolution (0.014 inch / revolution and 0.034 inch / revolution), preferably between and including 0.51 mm / revolution and 0.71 mm / revolution (0.020 inch / revolution and 0.028 inch / revolution).

[0206] The first internal thread 4 and the first external thread 12 are configured to have a first radial thread interference 37 upon final engagement 20. The first radial thread interference 37 between the first internal thread 4 and the first external thread 12 decreases in a first direction 21 from the inner edge 8 toward the first inner main seal 18 (see...). Figure 1A The second internal thread 6 and the second external thread 16 are configured to have a second radial thread interference 38 upon final engagement 20, the second radial thread interference 38 between the second internal thread 6 and the second external thread 16 decreasing in the opposite direction 23 from the inner edge 8 toward the second inner main seal 19 (see...). Figure 1A The reduced first radial thread interference 37 and the reduced second radial thread interference 38 respectively reduced the higher circumferential stress that appeared beyond the first and second seal initiation positions 22, 24 (when viewed in the first and second directions 21, 23) (see also) Figure 4 (The curve graph).

[0207] More specifically, the first radial thread interference 37 between the first internal thread 4 and the first external thread 12 decreases in the first direction 21 until it reaches zero, and the second radial thread interference 38 between the second internal thread 6 and the second external thread 16 decreases in the second direction 23 until it reaches zero. The first internal thread 4 and the first external thread 12, in the first direction 21 and beyond the first thread position 39, have no first radial thread clearance between the first internal thread 4 and the first external thread 12 (see...). Figure 9 (41) The first radial thread interference value reaches zero at the first thread position 39. The second internal thread 6 and the second external thread 16 are in the second direction 23 and beyond the second thread position 40 without the second radial thread clearance between the second internal thread 6 and the second external thread 16 (see Figure 9 42), the second radial thread interference value reaches zero at the second thread position 40.

[0208] In another alternative embodiment of the threaded connection, the first radial thread interference 37 between the first internal thread 4 and the first external thread 12 decreases in the first direction 21 until it reaches a first radial thread interference value greater than zero, and the second radial thread interference 37 between the second internal thread 6 and the second external thread 16 decreases in the second direction 23 until it reaches a second radial thread interference value greater than zero.

[0209] Figure 9 The taper angle of a second alternative embodiment of the threaded connection according to the invention is shown. This second alternative embodiment is related to... Figure 8 The difference in the threaded connection is that the first internal thread 4 and the first external thread 12 have a first radial thread clearance 41 between the first internal thread 4 and the first external thread 12 in the first direction 21 and beyond the first thread position 39, reaching a first radial thread interference value of zero at the first thread position 39, and the second internal thread 6 and the second external thread 16 have a second radial thread clearance 42 between the second internal thread 6 and the first external thread 16 in the second direction 23 and beyond the second thread position 40, reaching a second radial thread interference value of zero at the second thread position 40.

[0210] Detailed embodiments of the invention have been disclosed herein as needed; however, it should be understood that the disclosed embodiments are merely examples of the invention, which may be embodied in various forms. Therefore, the specific structural and functional details disclosed herein are not to be construed as limiting, but only as the basis for the claims and as a representative basis for teaching those skilled in the art to employ the invention in various ways in any suitable detailed structure. Furthermore, the terminology and phrases used herein are not intended to be limiting, but rather to provide an understandable description of the invention.

[0211] As used herein, the term "a" or "an" is defined as one or more. As used herein, the term "multiple" is defined as two or more. As used herein, the term "another" is defined as at least a second or more. As used herein, the term "comprising" and / or "having" is defined as including (i.e., open language, not excluding other elements or steps). Any reference numerals in the claims should not be construed as limiting the scope of the claims or the invention.

[0212] It will be apparent to those skilled in the art that various modifications can be made to the threaded connection without departing from the scope defined by the claims.

Claims

1. Threaded connection, used for exploration and production in hydrocarbon wells, and includes: - A connecting member having a connecting outer diameter (COD) and including The first sleeve portion includes a first internal thread. The second sleeve portion includes a second internal thread, and The edge portion includes a radially extending inner edge, wherein The edge portion is located between the first sleeve portion and the second sleeve portion, and has a radial edge portion thickness B and an axial edge portion length C, and The first sleeve portion and the second sleeve portion have radial sleeve portion thicknesses A located between the inner edge and the first internal thread and the second internal thread, respectively. - A first tubular member, comprising a first unthreaded tubular portion and a first pin portion including a first external thread, and - A second tubular member, comprising a second unthreaded tubular portion and a second pin portion including a second external thread, wherein -- The first and second unthreaded tube sections have an outer diameter TOD and a radial wall thickness W. -- The first tubular member and the second tubular member have an inner diameter TID. -- The first internal thread, the second internal thread, the first external thread, and the second external thread have dovetail wedge-shaped threads. -- The first internal thread and the first external thread are configured to form a first internal main seal upon final engagement. -- The second internal thread and the second external thread are configured to form a second internal main seal upon final engagement, and -- Threaded connection conforms to: COD > TOD B = approximately ((COD–TID) / 2) C > 0, and A < W.

2. The threaded connection according to claim 1, characterized in that, The threaded connection conforms to: C≤31.75 mm.

3. The threaded connection according to claim 2, characterized in that, The threaded connection conforms to the following specification: C≤27.94 mm.

4. The threaded connection according to claim 1, characterized in that, The threaded connection conforms to: C ≥ 6.35 mm.

5. The threaded connection according to claim 4, characterized in that, The threaded connection conforms to: C ≥ 10.16 mm.

6. The threaded connection according to claim 1, characterized in that, The threaded connection conforms to: 20.32 mm ≤ C ≤ 27.94 mm.

7. The threaded connection according to claim 1, characterized in that, The threaded connection conforms to the following specification: C = 25.4 mm.

8. The threaded connection according to claim 1, characterized in that, The threaded connection conforms to: A≤0.9W.

9. The threaded connection according to claim 8, characterized in that, The threaded connection conforms to: A≤0.8W.

10. The threaded connection according to claim 1, characterized in that, The threaded connection conforms to: A≥0.7W.

11. The threaded connection according to claim 1, characterized in that, The radial sleeve thickness A is located at the critical cross-section of the first sleeve and the second sleeve.

12. The threaded connection according to claim 1, characterized in that, The threaded connection conforms to: 114.3 mm ≤ TOD ≤ 244.48 mm.

13. The threaded connection according to claim 12, characterized in that, The threaded connection conforms to: 114.3 mm ≤ TOD ≤ 193.68 mm.

14. The threaded connection according to claim 13, characterized in that, The threaded connection conforms to: 114.3 mm ≤ TOD ≤ 139.7 mm.

15. The threaded connection according to claim 1, characterized in that, The threaded connection conforms to the following specifications: 6.3 mm ≤ W ≤ 12.7 mm.

16. The threaded connection according to claim 15, characterized in that, The threaded connection conforms to: 7.3 mm ≤ W ≤ 11.1 mm.

17. The threaded connection according to claim 1, characterized in that: - In a first direction from the inner edge and toward the first inner main seal, the first internal thread and the first external thread begin to fully contact at the first seal initiation position. - On the opposite direction from the inner edge and toward the second inner main seal, the second internal thread and the second external thread begin to fully contact at the starting position of the second seal. - The first seal starting position is located at an axial sealing distance D from the second seal starting position, and - Threaded connection conforms to: D > C.

18. The threaded connection according to claim 17, characterized in that, The threaded connection conforms to the following: 3.6 mm ≤ (DC) / 2 ≤ 9.9 mm.

19. The threaded connection according to claim 18, characterized in that, The threaded connection conforms to: 5 mm ≤ (DC) / 2 ≤ 7.7 mm.

20. The threaded connection according to claim 19, characterized in that, The threaded connection conforms to: (DC) / 2 = 6.1 mm.

21. The threaded connection according to claim 1, characterized in that, The radially extending inner edge is located between the first pin and the second pin.

22. The threaded connection according to claim 1, characterized in that, The first tubular member includes a first pin, the second tubular member includes a second pin, and when finally fastened, the first pin and the second pin are located at a certain distance from the inner edge.

23. The threaded connection according to claim 22, characterized in that, The radially extending inner edge is located between the first pin and the second pin.

24. The threaded connection according to claim 1, characterized in that, When finally fastened, the threaded connection is not further sealed internally.

25. The threaded connection according to claim 1, characterized in that: - The first internal thread and the first external thread together form the first thread step, and - The second internal thread and the second external thread together form the second thread step.

26. The threaded connection according to claim 25, characterized in that, The threaded connection has no further thread steps.

27. The threaded connection according to claim 25, characterized in that, The first and second thread steps are tapered thread steps.

28. The threaded connection according to claim 27, characterized in that: - Threaded connections define the longitudinal axis. - The first internal thread has a constant first internal thread taper angle α1 relative to the longitudinal axis. - The first external thread has a constant first external thread taper angle β1 relative to the longitudinal axis. - The first internal thread taper angle α1 and the first external thread taper angle β1 are equal to each other. - The second internal thread has a constant second internal thread taper angle α2 relative to the longitudinal axis. - The second external thread has a constant second external thread taper angle β2 relative to the longitudinal axis, and - The second internal thread taper angle α2 and the second external thread taper angle β2 are equal to each other.

29. The threaded connection according to claim 28, characterized in that, The first internal thread taper angle α1, the first external thread taper angle β1, the second internal thread taper angle α2, and the second external thread taper angle β2 have a diameter taper between 0.36 mm / revolution and 0.86 mm / revolution, and are within the range of 0.36 mm / revolution and 0.86 mm / revolution.

30. The threaded connection according to claim 29, characterized in that, The first internal thread taper angle α1, the first external thread taper angle β1, the second internal thread taper angle α2, and the second external thread taper angle β2 have a diameter taper between 0.51 mm / revolution and 0.71 mm / revolution, and are within the range of 0.51 mm / revolution and 0.71 mm / revolution.

31. The threaded connection according to claim 28, characterized in that, The first internal thread and the first external thread are configured to have a first radial thread interference upon final engagement, and the second internal thread and the second external thread are configured to have a second radial thread interference upon final engagement.

32. The threaded connection according to claim 27, characterized in that: - Threaded connections define the longitudinal axis. - The first internal thread has a constant first internal thread taper angle α1 relative to the longitudinal axis. - The first external thread has a constant first external thread taper angle β1 relative to the longitudinal axis. - The first internal thread taper angle α1 is greater than the first external thread taper angle β1. - The second internal thread has a constant second internal thread taper angle α2 relative to the longitudinal axis. - The second external thread has a constant second external thread taper angle β2 relative to the longitudinal axis, and - The second internal thread taper angle α2 is greater than the second external thread taper angle β2.

33. The threaded connection according to claim 32, characterized in that, The first internal thread taper angle α1 and the second internal thread taper angle α2 have an internal taper diameter between 0.41 mm / revolution and 0.91 mm / revolution, and the first external thread taper angle β1 and the second external thread taper angle β2 have an external taper diameter between 0.36 mm / revolution and 0.86 mm / revolution, and the external taper diameter β2 is within the range of 0.36 mm / revolution and 0.86 mm / revolution.

34. The threaded connection according to claim 33, characterized in that, The first internal thread taper angle α1 and the second internal thread taper angle α2 have an internal taper diameter between 0.56 mm / revolution and 0.76 mm / revolution, and the first external thread taper angle β1 and the second external thread taper angle β2 have an external taper diameter between 0.51 mm / revolution and 0.71 mm / revolution, and the external taper diameter β2 has an external taper diameter between 0.51 mm / revolution and 0.71 mm / revolution, and the external taper diameter β2 has an external taper diameter between 0.51 mm / revolution and 0.71 mm / revolution.

35. The threaded connection according to claim 32, characterized in that: - The first internal thread and the first external thread are configured to have a first radial thread interference upon final engagement. - The first radial thread interference between the first internal thread and the first external thread decreases in a first direction from the inner edge toward the first inner main seal. - The second internal thread and the second external thread are configured to have a second radial thread interference upon final engagement, and - The interference of the second radial thread between the second internal thread and the second external thread decreases in the opposite direction from the inner edge and toward the second inner main seal.

36. The threaded connection according to claim 35, characterized in that: - The first radial thread interference between the first internal thread and the first external thread decreases in the first direction until it reaches a first radial thread interference value of zero, and - The interference of the second radial thread between the second internal thread and the second external thread decreases in the second direction until it reaches a second radial thread interference value of zero.

37. The threaded connection according to claim 36, characterized in that: - The first internal thread and the first external thread in the first direction and beyond the first thread position have no first radial thread clearance between the first internal thread and the first external thread, and the first radial thread interference value reaches zero at the first thread position, and - The second internal thread and the second external thread are in the second direction and beyond the second thread position without the second radial thread clearance between the second internal thread and the second external thread, and the second radial thread interference value reaches zero at the second thread position.

38. The threaded connection according to claim 36, characterized in that: - The first internal thread and the first external thread have a first radial thread clearance between the first internal thread and the first external thread in the first direction and beyond the first thread position, and a first radial thread interference value that is zero at the first thread position, and - The second internal thread and the second external thread have a second radial thread clearance between the second internal thread and the second external thread in the second direction and beyond the second thread position, and the second radial thread interference value reaches zero at the second thread position.

39. The threaded connection according to claim 1, characterized in that, The connecting member includes a first release groove located between the first internal thread and the inner edge, and a second release groove located between the second internal thread and the inner edge.

40. The threaded connection according to claim 39, characterized in that, The radial sleeve thickness A of the first sleeve portion and the second sleeve portion is located at the first release groove and the second release groove, respectively.

41. The threaded connection according to claim 1, characterized in that, The outer diameter COD of the connection is the maximum diameter of the threaded connection.

42. The threaded connection according to claim 1, characterized in that, The edge portion has an edge inner diameter RID and the threaded connection conforms to: RID = TID ± 0.127 mm.

43. The threaded connection according to claim 42, characterized in that, The edge portion has an edge inner diameter RID and the threaded connection conforms to: RID=TID.

44. The threaded connection according to claim 42, characterized in that, The edge portion has an edge outer diameter ROD and the threaded connection conforms to: B = (ROD–RID) / 2.

45. The threaded connection according to claim 44, characterized in that, The threaded connection conforms to: COD = ROD.

46. ​​The threaded connection according to claim 1, characterized in that, The first sleeve portion has a first sleeve outer diameter FBOD, the second sleeve portion has a second sleeve outer diameter SBOD, and the threaded connection conforms to: COD=FBOD=SBOD.

47. The threaded connection according to claim 1, characterized in that, The threaded connection defines the longitudinal axis.

48. The threaded connection according to claim 47, characterized in that, The radial sleeve portion thickness A of the first sleeve portion and the second sleeve portion is located between the inner edge and the first internal thread and the second internal thread, respectively, in the axial direction along the longitudinal axis.

49. The threaded connection according to claim 47, characterized in that, The radial sleeve portion thickness A of the first sleeve portion and the second sleeve portion is measured in the radial direction relative to the longitudinal axis of the threaded connection.

50. The threaded connection according to claim 47, characterized in that, The connecting member includes an outer connecting surface that defines a connecting outer diameter COD, and the radial sleeve portion thickness A of the first sleeve portion and the second sleeve portion is measured from the outer connecting surface.

51. The threaded connection according to claim 47, characterized in that, The first pin of the first tubular member is located between the inner edge and the first unthreaded tube portion in the axial direction along the longitudinal axis, and the second pin of the second tubular member is located between the inner edge and the second unthreaded tube portion in the axial direction along the longitudinal axis.

52. The threaded connection according to claim 47, characterized in that, The edge portion and the inner edge completely surround the longitudinal axis.

53. The threaded connection according to any one of the preceding claims, characterized in that, The edge portion includes an inner edge surface that is nearly flush with the first inner surface of the first tubular member and the second inner surface of the second tubular member.

54. The threaded connection according to claim 53, characterized in that, The edge portion includes an inner edge surface, which is flush with the first inner surface of the first tubular member and the second inner surface of the second tubular member.

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