A high seal connection pressure containment tubing coupling

Abstract

The application belongs to the technical field of oil pipe couplings, and provides a high-sealing connection pressure-resistant oil pipe coupling, which comprises a coupling body, two symmetrical installation grooves are formed in the inside of the coupling body, the cross section of the installation groove is a circular truncated cone, an installation thread is arranged in the inside of the installation groove, an oil pipe is arranged in the inside of the installation groove, and the outer surface of the oil pipe is also provided with an installation thread, which is arranged in the inside of the installation groove through the installation thread, the structure of the high-sealing connection pressure-resistant oil pipe coupling, the installation thread is a trapezoidal thread, the thread bearing surface is provided with a reverse angle of a fixing ring, and the thread guide surface is an improved trapezoidal thread, so that the gap on the male buckle tooth peak is increased, and the gap on the inlet side is small, which not only strengthens the tensile strength, but also increases the compressive strength, the design has superior structural strength (including bending resistance and pressure resistance), can ensure that the joint does not fail due to unhooking, and is convenient to process.

Description

Technical Field

[0001] This invention relates to the field of tubing coupling technology, and more specifically, to a high-sealing, pressure-resistant tubing coupling. Background Technology

[0002] Oil drilling and production equipment is crucial for oil production. During operation, due to factors such as the environment, supporting facilities, and the skill level of operators, some components of the equipment will gradually become damaged, deformed, broken, or corroded. As the degree of damage increases, the technical condition of the equipment will deteriorate, inevitably leading to technical problems, reduced functionality and usability, and even rendering the entire machine unusable. Maintaining drilling and production equipment in good condition, improving efficiency, and extending its service life are goals pursued by drilling and production equipment managers and are also important ways for enterprises to improve economic benefits.

[0003] Currently, some existing two-pipe couplings are connected by a single tapered thread. However, as oil fields enter the middle and late stages of development, the water content, depth, and special wells of oil wells increase, and the working environment of water injection wells and gas wells becomes more severe. The requirements for the two-pipe couplings are becoming increasingly stringent. The root of the external thread of the single tapered thread connection is prone to stress concentration, resulting in fatigue fracture and accidents such as well tubing string breakage. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a high-sealing, pressure-resistant oil pipe coupling.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a high-sealing, pressure-resistant oil pipe coupling, comprising a coupling body, wherein two symmetrical mounting grooves are formed inside the coupling body, the mounting grooves have a frustum-shaped cross-section, the mounting grooves are provided with mounting threads, an oil pipe is disposed inside the mounting grooves, the outer surface of the oil pipe is also provided with mounting threads, and the oil pipe is disposed inside the mounting grooves through the mounting threads, wherein the mounting threads include a thread bearing surface and a thread guiding surface, and a reinforcing device is provided on the coupling body.

[0006] The present invention is further configured such that: the thread bearing surface has a reverse angle of 0-3°, and the thread guide surface angle has a 10° angle.

[0007] The present invention is further configured such that: the coupling body includes an inner tube, an anti-corrosion layer and a wear-resistant layer, the anti-corrosion layer is disposed on the outer surface of the inner tube, and the wear-resistant layer is disposed on the outer surface of the anti-corrosion layer.

[0008] The present invention is further configured such that: the reinforcing device includes a reinforcing ring, the inner surface of the reinforcing ring is fixedly connected to the outer surface of the coupling body, the outer surface of the reinforcing ring is provided with two opposite threads starting from its center, the outer surface of the reinforcing ring is threadedly connected with two symmetrical rotating tubes, the two rotating tubes are respectively provided on the two opposite threads of the reinforcing ring, the top and bottom of the coupling body are fixedly connected with fixing rings, and the interior of the fixing ring is movably connected to the surface of the oil pipe.

[0009] The present invention is further configured such that: a sliding groove is provided inside the fixed ring, the cross section of the sliding groove is cross-shaped, a clamping block is slidably connected inside the sliding groove, and limit blocks are fixedly connected to both the upper and lower sides of the clamping block. The surface of the limit block is slidably connected to the inside of the sliding groove, and a ball is provided on the top of the limit block.

[0010] The present invention is further configured such that a triangular block is fixedly connected to one side of the clamping block, and the cross-section of the triangular block is triangular.

[0011] The present invention is further configured such that: a sealing groove is formed on the inner surface of the fixing ring, a sealing ring is provided inside the sealing groove, the inside of the sealing ring is movably connected to the surface of the oil pipe, and a cavity is formed inside the reinforcing ring, and a reinforcing rod is fixedly connected inside the cavity.

[0012] The advantages of this invention are: 1. The structure of the high-sealing, pressure-resistant tubing coupling of this invention uses an improved trapezoidal thread with a fixed ring angle of -° on the thread bearing surface and a guide angle of °. This increases the clearance on the male thread peak and reduces the clearance on the inlet side, which not only strengthens tensile strength but also increases compressive strength. This design has superior structural strength (including bending and compressive strength), ensuring that the joint does not experience disengagement failure and is easy to process. It is especially suitable for large displacement and long horizontal well sections. The optimization of the thread geometry reduces various sticking phenomena, even in the case of insufficient thread oil, thus fully utilizing the potential of the thread material to meet the connection strength requirements. This thread not only has high connection strength, tensile strength, resistance to sticking, and no thread oil adhesion under pressure or tension, but also has superior mechanical properties. It is also easy to process and inspect, thereby reducing the cost of the joint.

[0013] 2. The high-sealing, pressure-resistant oil pipe coupling structure of the present invention uses two rotating tubes to move relative to each other, so that the rotating tubes are pressed against the tightening block by the inclined surface of the triangular block, thereby pressing the oil pipe against the tightening block. At the same time, the self-locking property of the thread fixes the position of the tightening block, thereby strengthening the connection between the coupling body and the oil pipe, making the connection between the coupling body and the oil pipe more stable and firm, and making it easier for workers to use the device.

[0014] 3. The high-sealing, pressure-resistant oil pipe coupling structure of the present invention, through the cooperation of the anti-corrosion layer and the wear-resistant layer, improves the corrosion resistance and wear resistance of the coupling body and extends the service life of the coupling body, making it easier for workers to use the device.

[0015] 4. The high-sealing, pressure-resistant oil pipe coupling structure of the present invention allows the rolling ball to roll between the limiting block and the sliding groove, thereby reducing the friction between the limiting block and the sliding groove. This allows the tightening block and the limiting block to move more smoothly inside the sliding groove, enabling the tightening block to more smoothly squeeze and position the oil pipe. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a high-sealing, pressure-resistant oil pipe coupling according to the present invention;

[0017] Figure 2 This is a schematic diagram of the reinforcing ring structure of the present invention;

[0018] Figure 3 This is a cross-sectional structural schematic diagram of the coupling body of the present invention;

[0019] Figure 4 This is a schematic diagram of the structure of the mounting thread plane of the present invention;

[0020] Figure 5 This is a schematic diagram of the structure of the fixing ring of the present invention;

[0021] Figure 6 This is a schematic diagram of the structure of the coupling body of the present invention;

[0022] Figure 7 This is a schematic diagram of the structure of the reinforcing ring plane of the present invention.

[0023] In the diagram: 1. Coupling body; 2. Oil pipe; 3. Fixing ring; 4. Mounting groove; 5. Triangular block; 6. Rotating pipe; 7. Reinforcing ring; 8. Threaded bearing surface; 9. Threaded guide surface; 10. Sliding groove; 11. Tightening block; 12. Limiting block; 13. Ball bearing; 14. Inner pipe; 15. Anti-corrosion layer; 16. Wear-resistant layer; 17. Sealing groove; 18. Sealing ring; 19. Chamber; 20. Reinforcing rod; 21. Mounting thread. Detailed Implementation

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0025] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0026] In this invention, unless otherwise stated, the directional terms such as "up" and "down" generally refer to the directions shown in the accompanying drawings, or to the vertical, perpendicular, or gravitational direction; similarly, for ease of understanding and description, "left" and "right" generally refer to the left and right shown in the accompanying drawings; "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0027] Please see Figure 1-7 The present invention provides the following technical solution: a high-sealing and pressure-resistant oil pipe coupling, comprising a coupling body 1, wherein two symmetrical mounting grooves 4 are opened inside the coupling body 1, the cross-section of the mounting grooves 4 is frustoconical, the mounting grooves 4 are provided with mounting threads 21 inside, the oil pipe 2 is arranged inside the mounting grooves 4, and the outer surface of the oil pipe 2 is also provided with mounting threads 21, which are arranged inside the mounting grooves 4 through the mounting threads 21. The mounting threads 21 include a thread bearing surface 8 and a thread guide surface 9, and a reinforcing device is provided on the coupling body 1.

[0028] Specifically, the installation thread 21 is a trapezoidal thread, the thread bearing surface 8 has a reverse angle of 0-3° to the fixed ring, and the thread guide surface 9 is an improved trapezoidal thread with an angle of 10°. This increases the gap on the male tooth peak and reduces the gap on the inlet side, which is not only to strengthen the tensile strength but also to increase the compressive strength.

[0029] This design boasts superior structural strength (including bending and compressive strength), ensuring the joint does not experience derailment and is easy to manufacture. It is particularly suitable for long, horizontal well sections with extensive displacement. Optimized thread geometry reduces various forms of sticking, even in situations where thread lubricant is scarce, thus fully utilizing the potential of the thread material to meet connection strength requirements. This thread not only possesses high connection strength, tensile strength, resistance to sticking, and excellent mechanical properties under pressure or tension without thread lubricant adhesion, but it is also easy to manufacture and inspect, thereby reducing joint costs.

[0030] Furthermore, the coupling body 1 includes an inner tube 14, an anti-corrosion layer 15, and a wear-resistant layer 16. The anti-corrosion layer 15 is disposed on the outer surface of the inner tube 14, and the wear-resistant layer 16 is disposed on the outer surface of the anti-corrosion layer 15.

[0031] Specifically, the anti-corrosion layer 15 is made of fluorocarbon coating, and the wear-resistant layer 16 is made of polyurethane varnish. Through the cooperation of the anti-corrosion layer 15 and the wear-resistant layer 16, the corrosion resistance and wear resistance of the coupling body 1 are improved to a certain extent, and the service life of the coupling body 1 is extended, making it easier for workers to use the device.

[0032] The reinforcing device includes a reinforcing ring 7. The inner surface of the reinforcing ring 7 is fixedly connected to the outer surface of the coupling body 1. The outer surface of the reinforcing ring 7 has two opposite threads starting from its center. The outer surface of the reinforcing ring 7 is threadedly connected to two symmetrical rotating tubes 6. The two rotating tubes 6 are respectively set on the two opposite threads of the reinforcing ring 7. The top and bottom of the coupling body 1 are fixedly connected to a fixing ring 3. The inside of the fixing ring 3 is movably connected to the surface of the oil pipe 2.

[0033] Furthermore, a groove 10 is provided inside the fixed ring 3. The groove 10 has a cross-shaped cross section. A clamping block 11 is slidably connected inside the groove 10. Limiting blocks 12 are fixedly connected to both the upper and lower sides of the clamping block 11. The surface of the limiting block 12 is slidably connected to the inside of the groove 10. A ball 13 is provided on the top of the limiting block 12. The ball 13 can roll between the limiting block 12 and the groove 10.

[0034] The rolling ball 13 can roll between the limiting block 12 and the slide groove 10, which reduces the friction between the limiting block 12 and the slide groove 10, allowing the clamping block 11 and the limiting block 12 to move more smoothly inside the slide groove 10, thereby allowing the clamping block 11 to squeeze and position the oil pipe 2 more smoothly.

[0035] Furthermore, a triangular block 5 is fixedly connected to one side of the clamping block 11, and the cross-section of the triangular block 5 is triangular.

[0036] After the operator screws the oil pipe 2 into the coupling body 1, the operator rotates the rotating pipe 6, causing the two rotating pipes 6 to move relative to each other. The rotating pipe 6 is pressed against the clamping block 11 by the inclined surface of the triangular block 5, thereby pressing the oil pipe 2 by the clamping block 11. At the same time, the self-locking property of the thread fixes the position of the clamping block 11, thereby strengthening the connection between the coupling body 1 and the oil pipe 2, making the connection between the coupling body 1 and the oil pipe 2 more stable and secure, and making it easier for the operator to use the device.

[0037] Furthermore, a sealing groove 17 is provided on the inner surface of the fixing ring 3, and a sealing ring 18 is provided inside the sealing groove 17. The inside of the sealing ring 18 is movably connected to the surface of the oil pipe 2. Through the mutual cooperation between the sealing ring 18 and the mounting thread 21, the sealing performance between the oil pipe 2 and the coupling body 1 can be improved to a certain extent, making the connection between the two oil pipes 2 more stable and enabling the device to operate more smoothly.

[0038] Furthermore, a cavity 19 is provided inside the reinforcing ring 7, and a reinforcing rod 20 is fixedly connected inside the cavity 19. The reinforcing rod 20 can increase the strength inside the reinforcing ring 7 to a certain extent, thereby increasing the strength of the coupling body 1 and enabling the coupling body 1 to connect and fix the oil pipe 2 more stably.

[0039] Working principle: This high-sealing, pressure-resistant oil pipe coupling is used by the operator who screws the oil pipe 2 into the coupling body 1. The operator then rotates the rotating pipe 6, causing the two rotating pipes 6 to move relative to each other. The rotating pipe 6 is pressed against the clamping block 11 by the inclined surface of the triangular block 5, thus pressing the oil pipe 2 against the clamping block 11. At the same time, the self-locking property of the thread fixes the position of the clamping block 11, thereby strengthening the connection between the coupling body 1 and the oil pipe 2, making the connection more stable and secure, and making it easier for the operator to use the device. The installation thread 21 is an improved trapezoidal thread with a reverse angle of 0-3° from the fixed ring on the thread bearing surface 8 and a 10° angle on the thread guide surface 9. This increases the gap on the male thread peak and reduces the gap on the inlet side, which not only strengthens the tensile strength but also increases the compressive strength. This design has superior structural strength (including bending and compressive strength), which not only ensures that the joint will not disengage but is also easy to process.

[0040] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0041] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0042] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0043] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high seal connection pressure containment tubing coupling comprising a coupling body (1) characterised in that: The inside of the coupling body (1) is provided with two symmetrical installation grooves (4), the cross section of the installation groove (4) is a circular truncated cone, the inside of the installation groove (4) is provided with an installation thread (21), the inside of the installation groove (4) is provided with an oil pipe (2), the outer surface of the oil pipe (2) is also provided with an installation thread (21), which is arranged in the inside of the installation groove (4) through the installation thread (21), the installation thread (21) comprises a threaded bearing surface (8) and a threaded guide surface (9), and the coupling body (1) is provided with a reinforcing device; The reinforcing device comprises a reinforcing ring (7), the inner surface of the reinforcing ring (7) is fixedly connected with the outer surface of the coupling body (1), the outer surface of the reinforcing ring (7) is provided with two opposite threads with the center thereof as a starting point, the outer surface of the reinforcing ring (7) is threadedly connected with two symmetrical rotating pipes (6), the two rotating pipes (6) are arranged on the two opposite threads of the reinforcing ring (7) respectively, and the top and the bottom of the coupling body (1) are fixedly connected with a fixing ring (3), and the inside of the fixing ring (3) is movably connected with the surface of the oil pipe (2).

2. A high seal connection pressure containment tubing coupling according to claim 1, characterized in that: The threaded bearing surface (8) has a reverse angle of 0-3°, and the threaded guide surface (9) is provided with an angle of 10º.

3. A high seal connection pressure containment tubing coupling as defined in claim 1, wherein: The coupling body (1) comprises an inner pipe (14), a corrosion-resistant layer (15) and a wear-resistant layer (16), the corrosion-resistant layer (15) is arranged on the outer surface of the inner pipe (14), and the wear-resistant layer (16) is arranged on the outer surface of the corrosion-resistant layer (15).

4. A high seal connection pressure containment tubing coupling as defined in claim 1, wherein: The inside of the fixing ring (3) is provided with a sliding groove (10), the cross section of the sliding groove (10) is cross-shaped, the inside of the sliding groove (10) is slidably connected with a jacking block (11), the upper and lower sides of the jacking block (11) are fixedly connected with a limiting block (12), the surface of the limiting block (12) is slidably connected with the inside of the sliding groove (10), and the top of the limiting block (12) is provided with a rolling ball (13).

5. A high seal connection pressure containment tubing coupling as defined in claim 4 wherein: One side of the jacking block (11) is fixedly connected with a triangular block (5), and the cross section of the triangular block (5) is triangular.

6. A high seal connection pressure containment tubing coupling as defined in claim 5 wherein: The inner surface of the fixing ring (3) is provided with a sealing groove (17), and the inside of the sealing groove (17) is provided with a sealing ring (18), and the inside of the sealing ring (18) is movably connected with the surface of the oil pipe (2).

7. A high seal connection pressure containment tubing coupling as defined in claim 6 wherein: The inside of the reinforcing ring (7) is provided with a cavity (19), and the inside of the cavity (19) is fixedly connected with a reinforcing rod (20).

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