CN116950578A - Pipe body sealing threaded connection structure - Google Patents

Abstract

The invention provides a pipe body sealing threaded connection structure, which comprises: the joint comprises an internal thread section and a first anti-torque lifting shoulder which are sequentially connected, wherein the internal thread section is provided with an internal thread, and the first anti-torque lifting shoulder is provided with a first anti-torque lifting shoulder; the pipe body is provided with a connecting section, the connecting section comprises a first external thread section, a second non-thread section without threads, a second external thread section and a second anti-torsion lifting shoulder which are connected in sequence, the first external thread section and the second external thread section are respectively provided with external threads matched with the internal threads, and the second anti-torsion lifting shoulder is provided with a second anti-torsion lifting shoulder matched with the first anti-torsion lifting shoulder. The pipe body sealing threaded connection structure has good sealing performance, is particularly suitable for oil pipe sleeves of curved section wellholes of well structures such as directional wells, horizontal wells and large-displacement wells, and realizes the sealing integrity of the whole oil sleeve pipe column.

Description

Pipe body sealing threaded connection structure

Technical Field

The invention relates to a pipe body sealing threaded connection structure, and belongs to the field of oil/casing pipes for energy exploration and development of petroleum, natural gas, coalbed methane and the like.

Background

In the process of energy exploration and development of petroleum, natural gas, coal bed gas and the like, oil and casing strings are required to be used for stabilizing a well wall to form an oil-gas channel. At present, a threaded connection mode is generally adopted to enable single oil and casing to form an oil casing string, and the threaded connection is required to have connection and sealing functions.

However, in the existing threaded sealing connection structure, especially in the well structure with a curved section of well bore such as a directional well, a horizontal well and a large displacement well, the oil casing in the curved section of well bore often bears larger pulling and pressing load due to the constraint of the well wall, so that the threaded connection part bears larger pulling and pressing load, and under the operation of the pulling and pressing load, the pipe body material is elastically deformed, so that the contact pressure of the sealing surface of the threaded connection structure is reduced, even the sealing surface is separated, and the sealing performance of the threaded connection structure is reduced, even fails, and the phenomena such as oil gas leakage and the like are caused.

Disclosure of Invention

The invention provides a pipe body sealing threaded connection structure, which at least solves the problems of poor sealing performance and the like of the threaded connection structure in the prior art.

The invention provides a pipe body sealing threaded connection structure, which comprises: the joint comprises an internal thread section and a first anti-torque lifting shoulder which are sequentially connected, wherein the internal thread section is provided with an internal thread, and the first anti-torque lifting shoulder is provided with a first anti-torque lifting shoulder; the pipe body is provided with a connecting section, the connecting section comprises a first external thread section, a second non-thread section without threads, a second external thread section and a second anti-torsion lifting shoulder which are connected in sequence, the first external thread section and the second external thread section are respectively provided with external threads matched with the internal threads, and the second anti-torsion lifting shoulder is provided with a second anti-torsion lifting shoulder matched with the first anti-torsion lifting shoulder.

According to an embodiment of the invention, the first external thread section comprises a first bottom tooth and a thread tooth provided on the first bottom tooth, and the second non-threaded section has an outer diameter smaller than the outer diameter of the first bottom tooth.

According to an embodiment of the invention, the connection of the second non-threaded section and the first external threaded section adopts an arc transition at the side facing the internal thread; and/or, at one side facing the internal thread, the joint of the second non-threaded section and the second external thread section adopts arc transition.

According to an embodiment of the invention, the radius of the arc is 2mm-5mm.

According to an embodiment of the invention, the number of threads of the first external thread section is equal to or greater than 14.

According to an embodiment of the present invention, the number of threads of the second external thread section is 2 to 3.

According to an embodiment of the invention, the length of the second non-threaded section is 2-3 times the pitch of the external thread.

According to an embodiment of the present invention, the connection section has a tapered structure, and the tapers of the first external thread section, the second non-thread section, and the second external thread section are the same.

According to an embodiment of the present invention, the internal thread is an API thread or a non-API thread.

According to one embodiment of the invention, the internal thread section is of a conical structure, and the taper of the internal thread section is less than or equal to 1:16.

According to an embodiment of the invention, the pitch of the internal thread is greater than or equal to 5.08mm.

According to an embodiment of the invention, the effective thread count of the internal thread segments is equal to or greater than 16.

According to an embodiment of the present invention, the first anti-torque shoulder portion includes a first non-threaded section and a step portion, the internal threaded section, the first non-threaded section and the step portion are sequentially connected, an axial direction of the first non-threaded section is the same as an axial direction of the internal threaded section, and an axial direction of the step portion is perpendicular to the axial direction of the internal threaded section; one end of the second anti-torque lifting shoulder is connected with the second external thread section, the end face of the other end is the second anti-torque lifting shoulder, the end face of the step part facing the second anti-torque lifting shoulder is the first anti-torque lifting shoulder, and the first anti-torque lifting shoulder is connected with the second anti-torque lifting shoulder to realize sealing; and/or one surface of the second anti-torque lifting shoulder part facing the internal thread section is connected with the surface of the first non-thread section to realize sealing.

According to an embodiment of the invention, the tubular body comprises an oil pipe and/or a casing.

In the invention, the second anti-torque lifting shoulder part of the pipe body is matched with the first anti-torque lifting shoulder part of the joint to form a metal-metal sealing structure of the end face of the pipe body and the end face of the joint (the joint and the pipe body are usually made of metal), namely, the pipe body and the joint sealing surface are sealed through contact pressure and contact surfaces, so that a threaded connection structure with high sealing performance is formed. The connecting section of the pipe body is provided with a non-threaded section, the non-threaded section is arranged between a first external threaded section provided with external threads and a second external threaded section provided with external threads, and the connecting section forms a non-complete threaded structure, so that after the threaded connection is buckled to form a sealed threaded connecting structure, the non-threaded section without a threaded tooth and the second anti-torque lifting shoulder can bear compression load, when the threaded connecting structure bears tension or compression load in the service process, the non-threaded section is free of a threaded tooth and is not buckled with the internal threaded section of a joint, and is not limited, the non-threaded section can bear tensile or compression stress, the second external threaded section is buckled with the internal threaded section of the joint, and is limited, the influence of the tension load on the second anti-torque lifting shoulder can be relieved and reduced through the connecting effect of the non-threaded section and the second external threaded section, for example, the elastic deformation of a second anti-torque lifting shoulder material is reduced, the second anti-torque lifting shoulder is stressed by the tension of the first anti-torque lifting shoulder, and the like, so that the contact surface (sealing surface) of the second anti-torque lifting shoulder and the first anti-torque shoulder is separated, and the like are avoided, the sealing surface contact phenomenon is good, the sealing surface is well contact, the performance is improved, the connecting structure and the sealing sleeve can be used as a sealing sleeve with the well, and the sealing sleeve with the high service performance, and the sealing sleeve with the well structure can be used as a well, and the sealing sleeve with the well, and the well structure.

Drawings

FIG. 1 is a schematic view of a pipe body seal threaded connection structure according to an embodiment of the present invention;

fig. 2 is a schematic structural view of a pipe body seal threaded connection structure according to an embodiment of the present invention, wherein B is an enlarged view of a region P in a.

Reference numerals illustrate:

1: a connection section;

2: a joint;

11: a first external thread segment;

12: a second external thread segment;

13: a second non-threaded section;

14: a second anti-torque lifting shoulder;

141: a second anti-torque shoulder;

21: an internal thread segment;

22: a first anti-torque shoulder;

23: a step portion;

231: a first anti-torque shoulder;

p: a region;

r: and (3) arc.

Detailed Description

The present invention will be further described in detail below with reference to examples of embodiments of the invention and the accompanying drawings, so that those skilled in the art can better understand the aspects of the invention. The following detailed description is merely illustrative of the principles and features of the present invention, and examples are set forth for the purpose of illustration only and are not intended to limit the scope of the invention. All other embodiments, which can be made by those skilled in the art based on the examples of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the description of the present invention, the terms "first", "second", etc. are used for descriptive purposes only, for example to distinguish between components that more clearly illustrate/explain the technical solution, and are not to be understood as indicating or implying a meaning such as number or order of technical features indicated.

Furthermore, in the description of the present invention, the numerical values and numerical ranges referred to are approximations, and may be affected by the specific operation of the measurement, manufacturing process, etc., to some extent, which may be considered negligible by those skilled in the art.

An embodiment of the present invention provides a pipe body sealing thread connection structure, as shown in fig. 1 and 2, including: the joint 2 (or coupling) comprises an internal thread section 21 and a first anti-torque shoulder which are connected in sequence, wherein the internal thread section 21 is provided with internal threads, and the first anti-torque shoulder is provided with a first anti-torque shoulder 231; the pipe body is provided with a connecting section 1, the connecting section 1 comprises a first external thread section 11, a second unthreaded section 13 without threads, a second external thread section 12 and a second anti-torsion lifting shoulder 14 which are connected in sequence, the first external thread section 11 and the second external thread section 12 are respectively provided with external threads matched with internal threads, and the second anti-torsion lifting shoulder 14 is provided with a second anti-torsion lifting shoulder 141 matched with the first anti-torsion lifting shoulder 231.

In the pipe body sealing threaded connection structure, the non-threaded section is arranged on the connecting section of the pipe body and is arranged between the first external threaded section provided with the external threads and the second external threaded section provided with the external threads, so that the connecting section forms an incomplete threaded structure, after the threaded connection is completed to form the sealing threaded connection structure, the non-threaded section without the threaded teeth and the second anti-torque lifting shoulder part bear compression loads, when the threaded connection structure bears tensile or compressive loads in the service process, the non-threaded section is not buckled with the internal threaded section of the joint and is not limited, the non-threaded section can bear tensile or compressive stress, the second external threaded section is buckled with the internal threaded section of the joint and is limited, the influence of the tensile load on the second anti-torque lifting shoulder part can be relieved and reduced through the connecting effect of the non-threaded section and the second external threaded section, for example, the elastic deformation of the second anti-torque lifting shoulder part is reduced, the second anti-torque lifting shoulder part is stressed by pulling force deviating from the first anti-torque lifting shoulder part and the like, and the contact surface (sealing surface) of the second anti-torque lifting shoulder part is prevented from being separated from the contact surface (sealing surface) of the first anti-torque lifting shoulder part, the sealing surface is well contacted with the sealing surface, and the service performance of the threaded connection structure is prolonged.

Specifically, the first thread section and the second thread section are in threaded connection with the internal thread section 21 of the joint 2, the second anti-torque lifting shoulder 14 is matched with the first anti-torque lifting shoulder, and the connecting section 1 and the joint 2 are in sealed connection through contact sealing of contact surfaces of the first anti-torque lifting shoulder and the second anti-torque lifting shoulder, so that a threaded connection structure with high sealing performance is formed.

The pipe body is of a hollow structure and is provided with a pipe body wall, the pipe body wall is surrounded to form a channel, and the external threads are arranged on the outer side (namely, the side away from the channel) of the pipe body wall. The threads are formed by thread teeth (protrusions on the bottom teeth), i.e. the corresponding positions on the outer side of the pipe body wall are provided with thread teeth, respectively forming a first external thread section 11 and a second external thread section 12, whereas the non-thread sections are not provided with thread teeth.

Specifically, the first external thread segment 11 includes a first bottom tooth and a thread tooth provided on the first bottom tooth, and the second external thread segment 12 includes a second bottom tooth and a thread tooth provided on the second bottom tooth, and the first bottom tooth, the non-thread segment, and the second bottom tooth are integrally formed.

In some embodiments, the outer diameter of the second non-threaded section 13 is smaller than the outer diameter of the first bottom tooth.

Specifically, the groove is formed at the second non-threaded section 13 on the side of the pipe wall facing the internal threaded section 21 of the joint 2, so that the external diameter of the second non-threaded section 13 is smaller than the external diameter of the first bottom tooth, and may also be smaller than the external diameter of the second bottom tooth, while the thickness of the pipe wall at the first external threaded section 11 (i.e. the thickness of the second external threaded section 12) is respectively larger than the thickness of the pipe wall at the second non-threaded section 13 (i.e. the thickness of the second external threaded section 12) at the second non-threaded section 13, the first external threaded section 11, the second external threaded section 12 (i.e. the thickness of the second external threaded section 12) at the second non-threaded section 13, and the side of the pipe wall facing the internal threaded section 21 of the joint 2 (i.e. the side of the pipe body, the channel) is flat (i.e. the side of the second non-threaded section 13 facing the internal threaded section 21, the first external threaded section 11, the side of the second external threaded section 11 facing the second external threaded section 11, and the side of the second external threaded section 12 facing the internal threaded section 21 form a flat surface).

In some embodiments, the connection of the second non-threaded section 13 to the first external threaded section 11 may take the form of an arc R transition at the side facing the internal thread, i.e. the first external threaded section 11 transitions to the second non-threaded section 13 through the arc R. Furthermore, on the side facing the internal thread, the connection of the second non-threaded section 13 to the second external thread section 12 may be made with an arc R, i.e. the second external thread section 12 may be made to transition to the second non-threaded section 13 by means of an arc R.

Specifically, the first external thread section 11, the second non-thread section 13, the second external thread section 12 enclose to establish into the recess, the opening of recess is towards internal thread section 21, the second non-thread section 13 forms the diapire of recess, first external thread section 11, the lateral wall that the second external thread section 12 formed the recess, the lateral wall of recess includes vertical portion and first flexion, the diapire of recess includes horizontal portion and second flexion, vertical portion, first flexion, second flexion, the horizontal portion meets in proper order, the axial of vertical portion is perpendicular with the axial of linkage segment 1, the axial of horizontal portion is parallel with the axial of linkage segment 1, first flexion and second flexion are connected and are formed circular arc R transition zone, circular arc R transition zone is parallel to the axial cross-section (or the projection) of linkage segment 1 promptly for circular arc R.

In some embodiments, the radius of the arc R is R, and the value of R may be in the range of 2mm-5mm, for example, 2mm, 3mm, 4mm, 5mm, etc.

Specifically, the axial direction of the connection section 1 is parallel to the direction from the first external thread section 11 to the second external thread section 12 (or from the second external thread section 12 to the first external thread section 11), and the axial direction of the connection section 1 is also substantially parallel to the axial direction of the internal thread section 21.

In some embodiments, the first external thread segment 11 is a main thread segment of the connecting segment 1, and its length is greater than the length of the second non-threaded segment 13, greater than the length of the second external thread segment 12, and greater than the length of the second anti-torque shoulder 14, and typically the length of the first external thread segment 11 is also greater than the sum of the lengths of the second non-threaded segment 13, the second external thread segment 12, and the second anti-torque shoulder 14.

In some embodiments, the length of the second unthreaded section 13 is 2 to 3 times the pitch of the external thread. Illustratively, as shown in fig. 1, the length of the second non-threaded section 13 is about 2 times the pitch of the external thread, and the number of threads at the position of the internal thread section 21 corresponding to the second non-threaded section 13 is 2.

In the present invention, the pitch of the external thread of the first external thread segment 11 is equal to the pitch of the external thread of the second external thread segment 12, that is, the length of the second non-threaded segment 13 is 2 to 3 times the pitch of the external thread of the first external thread segment 11, and is also 2 to 3 times the pitch of the external thread of the second external thread segment 12.

Specifically, the length of the first male thread section 11, the length of the second non-threaded section 13, the length of the second male thread section 12, the length of the second torque lifting shoulder 14 refer to the length thereof in the axial direction (length direction) of the connection section 1.

In some embodiments, the first external thread segment 11 has a thread count equal to or greater than 14, which is the complete thread count of the first external thread segment 11. Illustratively, as shown in FIG. 1, the first external thread segment 11 has a full thread count of 16.

In some embodiments, the second external thread segment 12 has a thread count of 2-3, which is the complete thread count of the second external thread segment 12. Illustratively, as shown in FIG. 1, the second external thread segment 12 has a full thread count of 2.

In general, the connection section 1 of the pipe body may have a conical structure, and the tapers of the first external thread section 11, the second non-thread section 13, and the second external thread section 12 are the same, i.e. the taper of the first bottom tooth, the taper of the second non-thread section 13, and the taper of the second bottom tooth are the same.

In some embodiments, the first bottom tooth of the first external thread segment 11 has an outer diameter that is greater than the outer diameter of the second bottom tooth of the second external thread segment 12, and the second external thread segment 12 has an outer diameter that is greater than the outer diameter of the second anti-torque shoulder 14.

Specifically, the outer diameters are diameters rather than radii.

Typically, the joint 2 has a hollow structure, and the inner wall thereof is provided with thread teeth to form an internal thread. The internal thread section 21 is provided with a complete internal thread, i.e. the position corresponding to the first external thread section 11, the position corresponding to the second non-threaded section 13 and the position corresponding to the second external thread section 12 are provided with thread teeth.

In some embodiments, the internal threads are API threads or non-API threads, i.e., API threads that conform to the API standard or non-API threads that do not conform to the API standard.

Typically, the internal thread segments 21 are tapered, and the taper of the internal thread segments 21 is less than or equal to 1:16.

In some embodiments, the pitch of the internal thread is greater than or equal to 5.08mm, i.e., the number of threads per 24.5mm length of the internal thread segment 21 is less than or equal to 6, i.e., the number of threads in any 24.5mm length region of the internal thread segment 21 is less than or equal to 6 along the length of the internal thread segment 21. Illustratively, the internal thread pitch satisfies: the number of threads corresponding to each 24.5mm internal thread length is 8.

In some embodiments, the effective thread count of the internal thread segment 21 is equal to or greater than 16, where the effective thread count refers to the thread count of the internal thread segment 21 that can be matched with the external thread of the connection segment 1, that is, the sum of the thread count of the internal thread segment 21 at the position corresponding to the first external thread segment 11, the thread count of the internal thread segment 21 at the position corresponding to the second non-thread segment 13, and the thread count of the internal thread segment 21 at the position corresponding to the second external thread segment 12. Illustratively, as shown in FIG. 1, the effective thread count of the internal thread segments 21 is 20.

Further, the total thread count of the internal thread section 21 (the total thread count of the internal thread section 21) may be equal to or greater than the effective thread count thereof, for example, the difference between the total thread count of the internal thread section 21 and the effective thread count thereof may be 0, 1,2, or the like. Illustratively, as shown in FIG. 1, the total thread count of the female thread section 21 is 21, which differs from the effective thread count of the female thread section 21 by 1.

Specifically, the second anti-torque shoulder 14 contacts with the contact surface of the first anti-torque shoulder to realize sealing, so that the pipe body sealing threaded connection structure with high sealing performance is formed. The contact surfaces of the two may be the anti-torque shoulder surface (end surface) of the first anti-torque shoulder and the anti-torque shoulder surface (end surface) of the second anti-torque shoulder 14, or the surface of the first anti-torque shoulder surface facing the connecting section 1 and the surface of the second anti-torque shoulder 14 facing the joint 2 (i.e. the conical surface or the cylindrical surface adjacent to the torque shoulder surface).

In particular, the first anti-torque shoulder may be of conical configuration (in which case the joint 2 is also generally of conical configuration), the face of which facing the connecting section 1 is conical; alternatively, the first anti-torque shoulder is of cylindrical configuration (in this case the joint 2 is also of generally cylindrical configuration), the face of which facing the connecting section 1 being cylindrical.

Furthermore, the second anti-torque shoulder 14 may be of conical configuration (in which case the pipe body and the connecting section 1 are also of generally conical configuration), the side facing the joint 2 being conical; alternatively, the second anti-torque shoulder 14 is of cylindrical configuration (in which case the tubular body and the connecting section 1 are also of generally cylindrical configuration), the face of which facing the joint 2 being cylindrical.

In some embodiments, the first anti-torque shoulder portion includes a first non-threaded section 22 and a step portion 23, the internal threaded section 21, the first non-threaded section 22, and the step portion 23 are sequentially connected, an axial direction of the first non-threaded section 22 is the same as an axial direction of the internal threaded section 21, and an axial direction of the step portion 23 is perpendicular to the axial direction of the internal threaded section 21.

One end of the second anti-torque shoulder portion 14 is connected to the second external thread section 12, the end face of the other end is the second anti-torque shoulder 141, the end face of the step portion 23 facing the second anti-torque shoulder portion 14 is the first anti-torque shoulder 231, and the first anti-torque shoulder 231 is connected to the second anti-torque shoulder 141 to achieve sealing (i.e. the contact surface of the first anti-torque shoulder and the second anti-torque shoulder 141 is the anti-torque shoulder surface).

In addition, the face of the second anti-torque shoulder 14 facing the internal thread segment 21 is in contact with the face of the first non-thread segment 22 (the face facing the second anti-torque shoulder 14) to effect a seal (i.e., the contact face of the two is a conical or cylindrical segment face bordering the torque shoulder face).

The pipe body can comprise an oil pipe and/or a casing pipe, so that the pipe body sealing threaded connection structure provided by the embodiment of the invention can be used for oil and casing strings in the process of energy exploration and development of petroleum, natural gas, coal bed gas and the like, and is particularly suitable for oil pipe sleeves of curved section wellholes of well body structures such as directional wells, horizontal wells, large displacement wells and the like, and the sealing integrity of the whole oil sleeve pipe column is realized.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A pipe body seal threaded connection structure, comprising:

the joint comprises an internal thread section and a first anti-torque lifting shoulder which are sequentially connected, wherein the internal thread section is provided with an internal thread, and the first anti-torque lifting shoulder is provided with a first anti-torque lifting shoulder;

the pipe body is provided with a connecting section, the connecting section comprises a first external thread section, a second non-thread section without threads, a second external thread section and a second anti-torsion lifting shoulder which are connected in sequence, the first external thread section and the second external thread section are respectively provided with external threads matched with the internal threads, and the second anti-torsion lifting shoulder is provided with a second anti-torsion lifting shoulder matched with the first anti-torsion lifting shoulder.

2. A pipe body sealing threaded connection as set forth in claim 1, wherein,

the first external thread section comprises a first bottom tooth and thread teeth arranged on the first bottom tooth, and the outer diameter of the second non-thread section is smaller than that of the first bottom tooth.

3. A pipe body sealing threaded connection as set forth in claim 1 or 2, characterized in that,

the joint of the second non-threaded section and the first external threaded section adopts arc transition at one side facing the internal thread; and/or the number of the groups of groups,

and at one side facing the internal thread, the joint of the second non-threaded section and the second external thread section adopts arc transition.

4. A pipe body sealing threaded connection according to claim 3, wherein the radius of the circular arc is 2mm-5mm.

5. A pipe body sealing threaded connection as set forth in claim 1, wherein,

the number of threads of the first external thread section is equal to or greater than 14; and/or the number of the groups of groups,

the number of threads of the second external thread section is 2-3; and/or the number of the groups of groups,

the length of the second non-threaded section is 2-3 times of the pitch of the external thread.

6. A tubular body seal threaded connection as set forth in claim 1 wherein the connection section is a tapered structure and the taper of the first externally threaded section, the second non-threaded section, and the second externally threaded section are the same.

7. A tubular body seal threaded connection as in claim 1, wherein the internal threads are API threads or non-API threads.

8. A pipe body sealing threaded connection as set forth in claim 1 or 7, characterized in that,

the internal thread section is of a conical structure, and the taper of the internal thread section is smaller than or equal to 1:16; and/or the number of the groups of groups,

the pitch of the internal thread is greater than or equal to 5.08mm; and/or the number of the groups of groups,

the effective thread count of the internal thread segments is equal to or greater than 16.

9. The pipe body sealing threaded connection structure according to claim 1, wherein the first torsion-resistant shoulder portion comprises a first unthreaded section and a step portion, the internal threaded section, the first unthreaded section and the step portion are sequentially connected, an axial direction of the first unthreaded section is the same as an axial direction of the internal threaded section, and an axial direction of the step portion is perpendicular to the axial direction of the internal threaded section; wherein,,

one end of the second anti-torque lifting shoulder is connected with the second external thread section, the end face of the other end is the second anti-torque lifting shoulder, the end face of the step part facing the second anti-torque lifting shoulder is the first anti-torque lifting shoulder, and the first anti-torque lifting shoulder is connected with the second anti-torque lifting shoulder to realize sealing; and/or

One surface of the second anti-torque lifting shoulder part facing the internal thread section is connected with the surface of the first non-thread section to realize sealing.

10. A tubular body seal threaded connection according to claim 1, wherein the tubular body comprises an oil pipe and/or a casing.