size of the threaded axial gap

Abstract

The invention relates to a tubular threaded seal (1) for drilling and exploitation of hydrocarbon wells, transport of oil and gas and carbon capture or geothermal energy, comprising a male tubular element (2) and a female tubular element (3), each of said male tubular element (2) and said female tubular element (3) comprising a male threaded portion (4) and a female threaded portion (5) respectively. Either of the male threaded portion (4) or the female threaded portion (5) optionally comprises an anticorrosion and / or lubricating solid coating (10), said male threaded portion (4) and said female threaded portion (5) comprising at least one male thread tooth (6) or at least one female thread tooth (5) respectively and a threaded axial gap TAG (8) providing a space between the engagement side (14) of said male thread tooth and the load bearing side (15) of said female thread tooth (7) in the mounted state, characterized in that said threaded axial gap TAG (8) is greater than or equal to a minimum gap TAG 最小 .

Description

Technical Field

[0001] This invention relates to steel components or pipelines in the fields of oil and gas, energy or storage, for uses such as well operation or hydrocarbon transportation, hydrogen and geothermal energy or carbon capture, etc. Background Technology

[0002] In this document, the term "component" refers to any element, accessory, or conduit used for drilling or operating a well, comprising at least one connector or even threaded end, and intended to be assembled by threaded connection to another component to form a threaded joint with the other component. The component may be, for example, a relatively long (particularly about 10 meters long) pipe or tubular element, such as a pipe several tens of centimeters long or even a tubular sleeve several tens of centimeters long, or even accessories to these tubular elements (suspension devices or "hangers," variable cross-section parts or "bridges," safety valves, connectors for drill pipe, or "tool joints," "short sections," etc.).

[0003] The component or pipe has threaded ends. These threaded ends are complementary, allowing both male (“male thread”) and female (“female thread”) tubular elements to be joined together. Therefore, male and female threaded ends are provided. Threaded ends, referred to as high-quality or semi-high-quality threaded ends, typically include at least one stop surface. A first stop may be formed by two surfaces of the two threaded ends, which are substantially radially oriented and configured to contact each other after the threaded ends are screwed together or during compressive stress. The stop typically has a negative angle relative to the main axis of the connection. Intermediate stops on joints, comprising at least two threaded steps, are also known. The threaded ends, stop surfaces, and sealing surfaces may form an assembly called a lip. There may be a lip with the thread oriented outwards, i.e., a male lip, and a lip with the thread oriented inwards, i.e., a female lip.

[0004] Machining a pipe to create threads implies the existence of a thread pitch. The concept of thread pitch must be understood according to ISO 5408:2009, which defines threads. Thread pitch must be controlled to avoid assembly problems and the use of joints between male and corresponding female threads.

[0005] Due to inaccuracies in the methods or threading tools used during machining, unpredictable deviations may occur between the pitch of the male or female thread and the theoretical pitch. This deviation is called pitch error. Some devices allow for the measurement of thread pitch and the determination or detection of pitch errors, thereby rejecting the affected threaded parts. Examples of measuring devices are described in API specification 5B, "Gauging and Inspection of Casing, Tubing, and Line Pipe Threads."

[0006] However, measurements may be inaccurate due to potential defects in the measuring equipment itself. Generally, safety standards and error ranges should also be considered for this type of equipment.

[0007] Problems may arise after screwing the male and female tubular elements together. In practice, it is difficult to measure the pitch in the engaged state, and therefore difficult to detect pitch errors. This can be addressed by analyzing the screwing curves (see...). Figure 10 Pitch errors can be detected, but by this stage it is too late, and the two tubes involved must be rejected. Rejection criteria are found in supplier specifications, such as in the "VAM Manual." Therefore, despite precautions and safety measures, some small pitch errors may occur during machining, which may be individually permissible and within acceptable error ranges. Thus, even though the tube contains acceptable small cumulative pitch errors, it can be validated and its industrial cycle can continue. Surprisingly, the applicant has been able to identify and determine that the cumulative pitch error may be individually permissible, but could lead to a misalignment of the thread flanks across the entire thread. When this accumulation and / or this misalignment exceeds a certain threshold, and when this accumulation and / or this misalignment is opposite on both male and female tubular elements, a pitch mismatch occurs, resulting in axial interference or mating problems between the thread flanks. Due to the compression of both the male and female thread teeth, this axial interference or mating problem can generate excessive stress at one or more locations on the thread. Excessive stress can cause mating between threads at excessively high turning speeds, hindering tightening because the correct positioning of the male portion relative to the female portion is no longer guaranteed. This can mean a risk of embrittlement or plasticization of the connection, as well as a decrease in sealing performance, which may lead to leaks. Leaks can have serious economic and even environmental consequences, as is the case in hydrocarbon wells during their operation.

[0008] When applying solid coatings with anti-corrosion or lubricating properties, the consequences of pitch mismatch and the resulting leakage problems become more prominent. Summary of the Invention

[0009] This invention allows for overcoming all the problems mentioned above. In particular, this invention proposes a configuration that eliminates the consequences of pitch error, and especially eliminates the accumulation of pitch error in the thread, while ensuring no axial interference or mating problems and ensuring sealing.

[0010] According to one embodiment, the present invention provides a tubular threaded joint for drilling and operation of hydrocarbon wells, and for the transportation of oil, gas, carbon capture materials, or geothermal energy. The tubular threaded joint includes a male tubular element and a female tubular element, each comprising a male thread portion and a female thread portion. Optionally, either the male or female thread portion includes an anti-corrosion and / or lubricating solid coating. Each of the male and female thread portions includes at least one male thread tooth or at least one female thread tooth and a thread axial clearance TAG. The thread axial clearance TAG, in the installed state, ensures the space between the insertion side of the male thread tooth and the load side of the female thread tooth. The thread axial clearance TAG is characterized in that the thread axial clearance TAG is greater than or equal to the minimum clearance TAG, such that:

[0011] [Mathematical Expression 1]

[0012]

[0013] And: 0 ≤ Ep coating ≤ Ep coating maximum

[0014] in:

[0015] The minimum axial clearance of the TAG thread, in mm.

[0016] The minimum value of the minimum pitch mismatch tolerance for IT, in mm.

[0017] The minimum axial length of the minimum male thread in LF type, in mm.

[0018] The minimum axial length of the LF female thread, in mm.

[0019] The minimum value of the minimum male thread pitch tolerance distance for D-type male threads, in mm.

[0020] The minimum tolerance distance for the minimum female thread pitch of the D-type thread, in mm.

[0021] The thickness value of the Ep coating for corrosion protection and / or lubrication, in mm.

[0022] Due to this feature, the connector according to the invention has a thread axial clearance (TAG) that meets a minimum threshold, thereby ensuring compensation for any thread misalignment caused by the accumulation of pitch errors. This accumulation may also be caused by several individual, acceptable pitch errors.

[0023] Surprisingly, when the equation is satisfied, the risk of pitch mismatch between different connectors is absorbed by a sufficiently large thread axial clearance. Therefore, any risk of axial interference due to offset caused by very significant pitch mismatch, and consequently embrittlement and plasticization, is completely eliminated.

[0024] The term "thread axial clearance" (TAG) refers to the distance separating the insertion face of the male thread tooth from the insertion face of the female thread tooth opposite to the insertion face of the male thread tooth, and it can be expressed in mm. This thread axial clearance is measured at half the height of the male tooth.

[0025] The term "pitch error" refers to the offset that occurs when comparing the actual pitch (measured on the manufactured part) with the pitch in the plane (originally defined in the product plan drawing).

[0026] The term “individually acceptable pitch error” refers to any pitch error of each thread that is small enough to be acceptable for verification during thread monitoring after machining, with reference values ​​defined in the plan and / or standard.

[0027] The term "pitch mismatch" refers to the difference between the cumulative pitch error on a male thread and the cumulative pitch error on a female thread.

[0028] At the same time, this equation also allows for monitoring of the degree of twisting.

[0029] According to one embodiment, the pitch mismatch tolerance value is included between 0.040 mm and 0.080 mm, preferably between 0.048 mm and 0.072 mm.

[0030] Due to this characteristic, pitch error can be measured using conventional monitoring devices, such as those described in API 5B1. In practice, if the pitch is below this tolerance, more expensive devices should be used, as the measurement results are not necessarily guaranteed. Tolerance values ​​greater than 0.080 mm are undesirable.

[0031] According to one embodiment, the tubular threaded joint is characterized in that the thread axial clearance TAG is less than or equal to the maximum clearance TAG, such that:

[0032] [Mathematical Expression 2]

[0033]

[0034] And: 0 ≤ Ep coating ≤ Ep coating maximum,

[0035] a = 0.00053,

[0036] b = 0.14,

[0037] in:

[0038] The surface area of ​​the male lip is the cross-sectional area of ​​the male lip located between the sealing surface and the stop surface, expressed in mm².

[0039] The slope value of the correlation.

[0040] b-intercept value,

[0041] The value for the thickness of the Ep coating, an anti-corrosion and / or lubricating solid coating, in mm.

[0042] This feature eliminates the risk of loss of sealing performance due to excessive axial clearance (TAG) in the thread.

[0043] The term "sealing performance" refers to the resistance of a connection to a combination of external / internal pressure and traction / compression stress. A seal can be a liquid seal or a gas seal.

[0044] Due to this feature, the joint according to the invention is more robust under compressive stress.

[0045] In fact, excessive axial clearance in the thread can lead to excessive stress at the lip, and thus plasticize when the connector is subjected to compressive stress. This overstress can cause leakage.

[0046] Therefore, the sealing of the connector is not only guaranteed when the equation is satisfied, but the applicant has also observed that the sealing performance of several types of connectors according to the present invention is improved.

[0047] According to one implementation, the thread axial clearance TAG is contained between the minimum and maximum TAG values, such that: minimum TAG < maximum TAG.

[0048] According to one embodiment, the tubular threaded joint 1 is characterized in that at least one of the male thread portion 4 and the female thread portion 5 includes an anti-corrosion and / or lubricating solid coating, and the thickness value Ep of the anti-corrosion and / or lubricating solid coating 10 is greater than zero.

[0049] Because of this characteristic, adding an anti-corrosion and / or lubricating solid coating to the threads increases the risk of unwanted axial interference. In fact, the thickness of the solid coating may help increase the contact pressure on the thread flanks, thereby increasing the risk of embrittlement or plasticization. The present invention, however, allows for screwing without the additional risk of embrittlement or plasticization of the connection due to the coating in the threads.

[0050] According to one embodiment, the tubular threaded joint is characterized in that the maximum thickness value of the anti-corrosion and / or lubricating solid coating Ep is equal to 0.0075 mm.

[0051] Because of this feature, the configuration can be combined with a variety of anti-corrosion and / or lubricating solid coatings, which eliminates the risk associated with pitch mismatch at a maximum of 0.0075 mm.

[0052] According to one embodiment, the anti-corrosion and / or lubricating solid coating includes a layer containing zinc and nickel. Attached Figure Description

[0053] The invention will be better understood during the following description of several specific embodiments of the invention with reference to the accompanying drawings, which are for illustrative purposes only and not for limiting purposes.

[0054] [ Figure 1 ] Figure 1 The tubular threaded joint according to the invention is schematically depicted in a longitudinal cross-sectional view, wherein the load side contacts.

[0055] [ Figure 2 ] Figure 2 The tubular threaded joint according to the invention is schematically depicted in a longitudinal cross-sectional view, wherein the insertion side contact is provided.

[0056] [ Figure 3 ] Figure 3 The male and female thread teeth of the tubular threaded joint according to the present invention are schematically depicted in longitudinal cross-sectional view.

[0057] [ Figure 4 ] Figure 4 The male end according to the invention is schematically depicted in a longitudinal cross-sectional view.

[0058] [ Figure 5 ] Figure 5 The female end according to the invention is schematically depicted in a longitudinal cross-sectional view.

[0059] [ Figure 6 ] Figure 6 The finite element analysis of a tubular threaded joint according to the prior art is schematically described using a longitudinal cross-sectional view.

[0060] [ Figure 7 ] Figure 7 The finite element analysis of the tubular threaded joint according to the present invention is schematically described using a longitudinal cross-sectional view.

[0061] [ Figure 8 ] Figure 8 The male tubular threaded element is schematically described using a longitudinal cross-sectional view.

[0062] [ Figure 9 ] Figure 9 The arrangement of the male and female threads after screwing according to the present invention is schematically illustrated in a longitudinal cross-sectional view.

[0063] [ Figure 10 ] Figure 10 The screwing curve of the tube according to the prior art is described, which includes the accumulation of unabsorbed pitch error.

[0064] [ Figure 11 ] Figure 11 The screwing curve according to the invention is described, which includes the accumulation of absorbed pitch error.

[0065] [ Figure 12 ] Figure 12 The tubular threaded joint is schematically depicted in a longitudinal cross-sectional view, including the accumulation of pitch error. Detailed Implementation

[0066] In the remainder of the specification, the terms “longitudinal,” “lateral,” “vertical,” “front,” “rear,” “left,” and “right” are defined according to a commonly used orthogonal reference system as shown in the accompanying drawings, which includes:

[0067] The horizontal longitudinal axis X, and it runs from left to right in the cross-sectional view;

[0068] Furthermore, in the specification and claims, as defined in the specification, the terms "external" or "internal," and "axial" and "radial," will be used to denote elements of a tubular threaded joint. The longitudinal axis X defines the "axial" orientation. The "radial" orientation points perpendicular to the longitudinal axis X.

[0069] Figure 1A tubular threaded connector 1 according to the present invention is described, comprising a male tubular element 2 and a female tubular element 3. The male tubular element 2 includes a male threaded portion 4, a male sealing surface 28, and a male stop portion 24. The female tubular element 3 includes a female threaded portion 5, a female sealing surface 29, and a female stop portion 25. The male threaded portion 4 and the female threaded portion 5 each include several male thread teeth 6 and female thread teeth 7 originating from the same thread helix. The definition of a thread helix is ​​given in ISO 5408. The male thread tooth 6 includes a male insertion side 14 and a male load side 12. The female thread tooth 7 includes a female insertion side 15 and a female load side 13.

[0070] Figure 1 The joint is represented as being subjected to tensile forces during its use, such as the weight of a column subjected to vertical tension in the direction of the arrow. Under this normal use, the male load side 12 and the female load side 13 are in contact. The male insertion side 14 and the female insertion side 15 are not necessarily in contact and define the space formed by the threaded axial clearance “TAG” thread. However, the stop and the sealing surface may be in contact.

[0071] Another method to define the axial clearance "TAG" of the thread is the difference between the width LCB of the recess between two female thread teeth and the width LP of the male thread tooth, such as... Figure 3 As shown in the image.

[0072] Figure 2 The following describes the situation of the tubular threaded connector 1 according to the invention under harsh operating conditions, such as when a temperature difference generates compressive force at the threaded connector. The connector will tend to deform under this compressive force. In this case, the male insertion side 14 contacts the female insertion side 15. The stress on the already contacting male sealing surface 28 and female sealing surface 29, as well as the male stop portion 24 and female stop portion 25, will increase. Interference at the male sealing surface 28 and female sealing surface 29, and at the male stop portion 24 and female stop portion 25, will increase.

[0073] Figure 2 This demonstrates that compression on the insert side cannot be increased or intensified indefinitely, and exceeding a certain limit may lead to undesirable axial interference, resulting in thread plasticization or even thread deterioration. Therefore, in the installation state where there is no stress between the male insert side 14 and the female insert side 15, too small an axial clearance in the thread causes this to worsen.

[0074] Figure 3Details of the tubular threaded connector 1 according to the invention are shown, particularly the male thread tooth 6 and the female thread tooth 7 in the installed state. The male thread tooth 6 includes a male load side 12 and a male insertion side 14. The female thread tooth 7 includes a female load side 13 and a female insertion side 15. The male insertion side 14 and the female insertion side 15 define a space whose axial dimension is the thread axial clearance “TAG”. The thread axial clearance TAG is greater than or equal to the minimum clearance TAG, such that:

[0075] [Mathematical Expression 3]

[0076]

[0077] And: 0 ≤ Ep coating ≤ Ep coating maximum,

[0078] in:

[0079] The minimum axial clearance of the TAG thread, in mm.

[0080] The minimum value of the minimum pitch mismatch tolerance for IT, in mm.

[0081] The minimum axial length of the minimum male thread in LF type, in mm.

[0082] The minimum axial length of the LF female thread, in mm.

[0083] The minimum value of the minimum male thread pitch tolerance distance for D-type male threads, in mm.

[0084] The minimum tolerance distance for the minimum female thread pitch of the D-type thread, in mm.

[0085] The thickness value of the Ep coating for corrosion protection and / or lubrication, in mm.

[0086] Another way to define the thread axial clearance “TAG” is the difference between the width LCB of the recess between the two female thread teeth and the width LP of the male thread tooth, which is obtained at the middle height of the male thread 6.

[0087] The minimum TAG corresponds to a minimum threshold from which the effect of any thread offset caused by the accumulation of pitch error is offset. This accumulation can also originate from several individual acceptable pitch errors. Figure 12 The diagram illustrates the accumulation of pitch error and the resulting exacerbation.

[0088] The minimum clearance TAG is determined based on the following: the minimum value of pitch mismatch tolerance IT, the minimum value of axial length of male thread LF (male thread), the minimum value of axial length of female thread LF (female thread), the minimum value of pitch tolerance distance of male thread D (male thread), and the minimum value of final pitch tolerance distance of female thread D (female thread).

[0089] Threaded joints may include thread coatings, and therefore the additional parameter of coating thickness Ep must be considered. Figure 3 In the case of , there is no coating, and therefore Ep coating is equal to 0.

[0090] The terms "axial length LF (minimum for male thread) or axial length LF (minimum for female thread)" refer to the total length of the thread along the thread axis of the pipe. The total thread length is measured from the root of the first tooth to the root of the last tooth. Figure 4 and Figure 5 As shown in the diagram.

[0091] The term "minimum male thread pitch tolerance D" or "minimum female thread pitch tolerance D" refers to the length of the monitored thread pitch, i.e., the total length of a perfect thread. A perfect thread can be defined as the opposite of an imperfect thread, i.e., a thread with incomplete height. A perfect thread is also referred to as the end thread in contrast to an imperfect thread.

[0092] The term "tolerance for pitch error" refers to the acceptable deviation of pitch error relative to the nominal plane.

[0093] The term "pitch mismatch tolerance" refers to the difference between the pitch error tolerance of the male screw and the pitch error tolerance of the female screw.

[0094] The term "pitch" refers to the distance between two consecutive loaded sides as defined by ISO 5408.

[0095] The minimum pitch mismatch tolerance value IT can be between 0.040 mm and 0.080 mm, preferably between 0.048 mm and 0.072 mm. Therefore, pitch error can be measured using conventional monitoring devices, such as those described in API 5B1. In practice, below this minimum value, it is necessary to use more expensive equipment whose measurement results are not necessarily guaranteed. Above this maximum value, the minimum thread axial clearance TAG is too large.

[0096] It should be noted that the minimum value of TAG indirectly depends on the axial length of the thread.

[0097] To simplify the method, empirical values ​​for minimum IT and minimum TAG for pipe fittings have been determined based on the nominal outer diameter OD of the pipe, and these empirical values ​​are given in Table 1 below:

[0098] [Table 1]

[0099]

[0100] Figure 4 The male end portion 20 according to the invention is shown in longitudinal cross-section. The male end portion 20 includes a male lip 22 and a metal body 18. The male lip includes a male threaded portion 4, a male stop surface 24, and a male sealing surface 28. The male threaded portion 4 includes several male thread teeth 6 that extend continuously along the thread root line Y. The thread axis is parallel to the longitudinally extending axis X.

[0101] The male or female pitch tolerance corresponds to the length of the pitch being monitored, that is, the total length of a perfect thread. A perfect thread can be defined in contrast to an imperfect thread, i.e., a thread with a significantly incomplete length. A perfect thread is also referred to as the end thread relative to an imperfect thread. For the male thread end 20, the pitch tolerance is defined by the minimum D-axis.

[0102] Figure 5 The female end portion 21 according to the invention is illustrated in a longitudinal cross-sectional view. The female end portion 21 includes a female lip 23 and a metal body 18. The female lip includes a female threaded portion 5, a female stop surface 25, and a female sealing surface 29. The female threaded portion 5 includes several thread teeth 7 that extend continuously along and from the thread root line Y. The thread axis is parallel to the longitudinally extending axis X.

[0103] Figure 6 A longitudinal cross-sectional view schematically illustrates a tubular threaded joint 61 with stress represented by finite element analysis (FEA) according to the prior art. The tubular threaded joint 61 includes a male tubular element 62 and a female tubular element 63. The male tubular element 62 includes a male threaded portion 64, a male sealing surface 28, and a male stop portion 24. The female tubular element 63 includes a female threaded portion 65, a female sealing surface 29, and a female stop portion 25. Figure 6 In this case, for a connector with an outer diameter OD of 139.7 mm, the thread axial clearance (TAG) of the connector is 0.250 mm. Referring to Table 2 below, the 0.250 mm clearance is greater than the maximum TAG value shown for a connector with a nominal outer diameter of 139.7 mm.

[0104] Figure 6 The darker areas correspond to regions of plasticization caused by mechanical compression, which can be observed, for example, in finite element analysis (FEA). Figure 6Two distinct plasticized areas can be observed: the first is the plasticized area of ​​the male sealing surface 28, and the second is the plasticized area of ​​both the male stop portion 24 and the female stop portion 25. Plasticization of the stops can be considered normal and expected. However, unlike the plasticization of the stops, the plasticization of the male sealing surface 28 is unacceptable and poses a major risk of leakage or failure.

[0105] Figure 7 The tubular threaded joint 1 according to the present invention, derived from finite element analysis, is schematically depicted in a longitudinal cross-sectional view. The tubular threaded joint 1 includes a male tubular element 2 and a female tubular element 3. The male tubular element 2 includes a male threaded portion 4, a male sealing surface 28, and a male stop portion 24. The female tubular element 3 includes a female threaded portion 5, a female sealing surface 29, and a female stop portion 25. Figure 7 The joint at the thread is different Figure 6 The connector in the middle, Figure 7 The joints in the middle are arranged to make Figure 7 The thread axial clearance TAG of the connector is 0.120 mm, which is smaller than the maximum TAG of the connector. Finite element analysis (FEA) shows that the male sealing surface 28 does not undergo plasticization. In the configuration according to the invention, the thread axial clearance TAG is small enough that the insertion sides of the male and female thread teeth contact each other without reaching the stage of plasticization of the sealing surface. Under these conditions, the threads are in full contact without interference during deceleration or compensating for compressive forces. This improves the seal. Therefore, the threads act as supports without being damaged and solve the problem. Figure 2 The exacerbation of the problem discussed in the article.

[0106] Figure 8 A male tubular element 2 according to the present invention is shown. The male tubular element 2 has a longitudinal axis X and includes a male lip 22, a male threaded portion 4 and a male stop portion 24.

[0107] The thread axial clearance TAG is defined relative to the surface area of ​​the male lip cross section A, known as the "male thread lip surface area." In other words, the cross section of the male tubular element at the male lip lies between the sealing surface and the stop surface. The thread axial clearance TAG is less than or equal to the maximum clearance TAG, such that:

[0108] [Mathematical Expression 4]

[0109]

[0110] And: 0 ≤ Ep coating ≤ Ep coating maximum,

[0111] a = 0.00053,

[0112] b = 0.14,

[0113] in:

[0114] The surface area of ​​the male lip is the cross-sectional area of ​​the male lip between the sealing surface and the stop surface, expressed in mm².

[0115] The slope value of the correlation.

[0116] b-intercept value,

[0117] The thickness value of the Ep coating for corrosion protection and / or lubrication, in mm.

[0118] The term “cross-sectional area A of male lip 22” refers to the following surface area: defined by one side of the convex stop 24, the profile 31 of the outer surface or threaded side, the inner surface profile 32 opposite to the outer surface, and finally defined by the radially oriented segment 34, which passes through the midpoint of the male sealing surface 28.

[0119] The maximum clearance TAG is determined relative to the size of the male tubular element 2 or the size of the male threaded end 20 of the male tubular element, taking into account the female tubular element 3 or the corresponding female threaded end 21 of the female tubular element, which is sized so that the sealing surface contacts after the male threaded end 20 and the female threaded end 21 are assembled.

[0120] “a” is the slope value of the correlation, and “b” is the intercept value of the line representing the maximum TAG as a function of the surface area of ​​the common lip.

[0121] For the purpose of simplification, the applicant has calculated a set of actual values ​​for the maximum value of TAG based on the nominal diameter of the pipe.

[0122] [Table 2]

[0123]

[0124] As shown in the examples in Tables 1 and 2, the minimum and maximum values ​​for TAG may vary depending on the connector.

[0125] According to one aspect of the invention, the thread axial clearance TAG is contained between the minimum and maximum TAG values, therefore:

[0126] The smallest tag is less than the largest tag.

[0127] Because of this feature, for the same type of connector or size, the thread axial clearance TAG can be determined, which meets the minimum threshold, thereby ensuring compensation for the effects of thread offset caused by the accumulation of pitch error, while eliminating the risk of loss of sealing performance caused by the accumulation of pitch error.

[0128] Figure 9 Embodiments of the present invention comprising a solid or semi-solid coating are described. This coating provides lubrication and / or corrosion protection. Such coated joints are becoming increasingly common to avoid the use of thread grease. Figure 9 A tubular threaded connector 1 according to the invention is described, particularly in a cross-sectional view along the longitudinal axis X, showing the male thread tooth 6 and female thread tooth 7 in their assembled state. The male thread tooth 6 includes a male load side 12 and a male insertion side 14. The female thread tooth 7 includes a female load side 13 and a female insertion side 15. The male insertion side 14 and female insertion side 15, as well as the male load side 12 and female load side 14, include an anti-corrosion and / or lubricating solid coating 10. One way to define the thread axial clearance “TAG” is the difference between the width LCB of the recess between the two female thread teeth and the width LP of the male thread tooth. The thread axial clearance TAG is greater than or equal to the minimum clearance TAG minimum, such that:

[0129] [Mathematical Expression 5]

[0130]

[0131] And: 0 ≤ Ep coating ≤ Ep coating maximum,

[0132] in:

[0133] The minimum axial clearance of the TAG thread, in mm.

[0134] The minimum value of the minimum pitch mismatch tolerance for IT, in mm.

[0135] The minimum axial length of the minimum male thread in LF type, in mm.

[0136] The minimum axial length of the LF female thread, in mm.

[0137] The minimum value of the minimum male thread pitch tolerance distance for D-type male threads, in mm.

[0138] The minimum tolerance distance for the minimum female thread pitch of the D-type thread, in mm.

[0139] The thickness value of the Ep coating for corrosion protection and / or lubrication, in mm.

[0140] Figure 3 The development of China is applicable Figure 9In this configuration, the coating thickness Ep is multiplied by a factor of 4, which takes into account the thickness of the four coating layers present on both the male insertion side 14 and the female insertion side 15, as well as on both the male load side 12 and the female load side 13. The parameter 4*Ep in the equation helps to minimize the TAG. In this case, Ep is the average of the combined thicknesses of the male load side 12 and the female load side 13, as well as the male insertion side 14 and the female insertion side 15, but the invention can also provide different thicknesses of Ep depending on the relevant insertion side or load side. The coating thickness Ep is the average thickness of the coating on the threaded side.

[0141] The thickness of a solid coating can increase contact pressure on the threaded sides, thereby increasing the risk of embrittlement or plasticization. This invention eliminates the additional risk of embrittlement or plasticization of the connector due to the presence of such a coating during screwing.

[0142] According to the supplementary aspect, the maximum thickness value Ep of the anti-corrosion and / or lubricating solid coating 10 is at most equal to 0.0075 mm. Preferably, the thickness of the coating 10 is between 0.0010 mm and 0.0075 mm.

[0143] Because of this feature, the configuration can be combined with a variety of anti-corrosion and / or lubricating solid coatings, which ensures that any risk of pitch mismatch with a maximum thickness of 0.0075 mm is absorbed.

[0144] The anti-corrosion and / or lubricating solid coating 10 may include a layer containing zinc and nickel, which has excellent anti-corrosion and lubrication properties.

[0145] When the present invention includes coating 10, Figure 9 The development in this context applies to all or part of the male thread portion 4 and the female thread portion 5.

[0146] Figure 10 The diagram illustrates the screwing curve of a pipe according to the prior art, including the accumulation of unabsorbed pitch errors. One method for ensuring proper assembly of connectors involves monitoring the torque applied by a clamp based on the number of revolutions. The term "clamp" refers to a high-capacity self-locking wrench used to clamp and apply tightening / loosening torque to the male and female parts of a connector. By connecting a computer to a load sensor and an electronic rotation counter on the clamp, the following graph can be plotted: This graph shows the torque on the vertical axis and the number of revolutions on the horizontal axis, as shown... Figure 10 As shown in the image.

[0147] The first part "I" corresponds to the tightening step, where there is contact between the threads, more specifically, at least between the corresponding insertion sides of the male thread end 20 and the female thread end 21. At this point, the resistance present for the first few turns is minimal until the corresponding threads begin to interfere radially. The second part "II" corresponds to the contact between the male and female sealing surfaces, and this results in the first sharp increase in the curve. Finally, the last part "III" corresponds to the contact between the stop surfaces of the male and female tubular threaded elements, which produces a sudden increase in torque when the male and female components rotate slightly relative to each other.

[0148] Since it is impossible to obtain the same torque every time two tubular threaded elements are screwed together, there is an acceptance window, which is determined by... Figure 10 and Figure 11 The two solid lines in the diagram are shown as twisted curves. Therefore, by... Figure 10 The dashed curve in the graph shows that the accumulated unabsorbed pitch error caused by this configuration will lead to a misalignment during the tightening stage, which can be seen as a curve outside the acceptance window on the graph. However, at this stage, it is too late; the tube may no longer be usable or repaired, and therefore the tube is likely to be rejected, resulting in a loss.

[0149] Figure 11 The dashed screw-in curve of the connector assembly according to the invention is shown, which includes the accumulation of absorbed pitch error. The thread axial clearance is large enough to absorb any accumulation of pitch error. Therefore, there is no offset, and thus the curve is well contained within the acceptable window represented by the two solid screw-in curves.

[0150] Figure 12 The overlapping first male thread end 20 and second male thread end 40 are shown, each comprising male thread portions 4a and 4b. Each male thread tooth 6 includes a male load side 12 and a male insertion side 14. The portion 4a of the first male thread end 20, indicated by a solid line, does not include the following pitch error: this pitch error corresponds to the theoretical value D (minimum tolerance) in mm, representing either the value in the plane or the minimum distance corresponding to the male thread pitch tolerance. The portion 4b of the second male thread end 40 is distinguished by a dashed line, thus showing the offset of the load side, which includes the accumulation of pitch error and corresponds to the true value Vr.

[0151] Both the first male thread end 20 and the second male thread end 40 include multiple thread pitches, corresponding to... Figure 12 The position level "n" is represented by "n-1", "n", "n+1", etc., indicating an increase or decrease.

[0152] The term "pitch" refers to the distance between two consecutive male or female load sides as defined by ISO 5408.

[0153] exist Figure 12 In this context, the pitch is defined by continuous male load sides. The theoretical minimum tolerance D corresponds to the value in the plane of the total pitch under consideration. By comparing the theoretical minimum tolerance D with the actual value Vr, the difference caused by the offset due to the accumulation of pitch error can be noted. This difference corresponds to the minimum value IT of the pitch mismatch tolerance.

[0154] An exemplary implementation of the configuration according to the present invention can be obtained by following these steps:

[0155] The male threaded element and the female threaded end were machined using a CNC lathe. Machining was performed on the male threaded end, which had a total length of 96.94 mm. Pitch error was monitored on the male threaded end within a length range of minimum male thread diameter (Dmale) of 55.88 mm. A shaped machining insert, with a shape opposite to the male threaded recess, was used for machining. The insert had a width of 2.567 mm and a machined pitch of 5.08 mm. Machining was performed on the female threaded end, which had a length of 82.98 mm, and pitch error was monitored within a length range of 76.20 mm. A shaped insert with a width of 2.647 mm and a machined pitch of 5.08 mm was used for machining.

[0156] Optionally, the present invention may include the following steps:

[0157] These threaded components were sandblasted using F80 brown fused alumina.

[0158] ZnNi was coated onto the two threaded elements by electrodeposition;

[0159] Chromium III passivation was applied to two threaded components by dip-coating;

[0160] A lubricating solid coating is applied to the two threaded elements by pneumatic spraying.

Claims

1. A tubular threaded joint (1) for drilling and operation of hydrocarbon wells, transportation of oil and gas, transportation or storage of hydrogen and carbon capture materials or geothermal energy, the tubular threaded joint (1) comprising a male tubular element (2) and a female tubular element (3), the male tubular element (2) and the female tubular element (3) respectively comprising a male thread portion (4) and a female thread portion (5), either the male thread portion (4) or the female thread portion (5) comprising an anti-corrosion and / or lubricating solid coating (10), the male thread portion (4) and the female thread portion (5) respectively comprising at least one male thread tooth (6) and at least one female thread tooth (7) and a thread axial clearance TAG (8), the thread axial clearance TAG (8) ensuring, in the installed state, the space between the insertion side (14) of the male thread tooth and the load side (15) of the female thread tooth (7), characterized in that, The axial thread clearance TAG is greater than or equal to the minimum clearance TAG minimum, such that: [Mathematical formula 6] And: 0 ≤ Ep coating ≤ Ep coating maximum, Where: TAG minimum The minimum value of the axial thread clearance, in mm, IT minimum The minimum value of the pitch mismatch tolerance, in mm, LF male The minimum value of the axial length of the minimum male thread, in mm, LF female The minimum value of the axial length of the minimum female thread, in mm, D male The minimum value of the pitch tolerance distance of the minimum male thread, in mm, D female The minimum value of the pitch tolerance distance of the minimum female thread, in mm, Ep coating The thickness value of the anti-corrosion and / or lubricating solid coating, in mm, Ep coating maximum The maximum thickness value of the anti-corrosion and / or lubricating solid coating, in mm.

2. The tubular threaded joint (1) according to claim 1, characterized in that, The value of the pitch mismatch tolerance is included between 0.040 mm and 0.080 mm.

3. The tubular threaded joint (1) according to claim 1 or 2, characterized in that, The axial thread clearance TAG is less than or equal to the maximum clearance TAG maximum, such that: [Mathematical formula 7] And: 0 ≤ Ep coating ≤ Ep coating maximum, a=0.00053， b=0.14， Where: The surface area of ​​the male lip, expressed in mm, is the cross-sectional area of ​​the male lip located between the sealing surface and the stop surface. 2 , a The slope value of the correlation, b The intercept value.

4. The tubular threaded joint (1) according to claim 3, characterized in that, The axial thread clearance TAG (8) is included between TAG minimum and TAG maximum, such that: TAG minimum < TAG maximum.

5. The tubular threaded joint (1) according to claim 1 or 2, characterized in that, At least one of the male thread portion (4) and the female thread portion (5) includes an anti-corrosion and / or lubricating solid coating, and the thickness value Ep coating of the anti-corrosion and / or lubricating solid coating (10) is greater than zero.

6. The tubular threaded joint (1) according to claim 5, characterized in that, The maximum value Ep coating maximum of the thickness of the anti-corrosion and / or lubricating solid coating (10) is equal to 0.0075 mm.

7. The tubular threaded joint (1) according to claim 1 or 2, characterized in that, The anti-corrosion and / or lubricating solid coating (10) includes a layer containing zinc and nickel.

8. The tubular threaded joint (1) according to claim 1, characterized in that, The value of the pitch mismatch tolerance is included between 0.048 mm and 0.072 mm.

Images