Wellhead jackscrew sealing device

Abstract

The utility model relates to the technical field of oil exploitation equipment, and discloses a wellhead jackscrew sealing device which comprises a four-way body, a jackscrew, a packing gland nut and a sealing assembly, and mounting holes are formed in the peripheral side of the four-way body at intervals; the mounting hole comprises a first hole section and a second hole section which are communicated in sequence, one end of the first hole section penetrates through the outer peripheral wall of the four-way body, and one end of the second hole section penetrates through the inner peripheral wall of the four-way body; the jackscrew is arranged in the mounting hole in a penetrating mode, the sealing assembly and the packing gland nut are sequentially arranged on the periphery of the jackscrew in a sleeving mode, and the sealing assembly is pressed on the connecting end face of the first hole section and the second hole section through the packing gland nut. The anti-extrusion ring and the check ring are sequentially connected and arranged at the two ends of the sealing ring respectively, and the anti-extrusion ring is closer to the sealing ring relative to the check ring; the sealing performance of the wellhead jackscrew sealing device can be effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of oil extraction equipment technology, specifically to a wellhead top screw sealing device. Background Technology

[0002] In oil and gas extraction, casing heads and tubing heads are crucial, and the top screw sealing assembly is an important component. During drilling and casing / oil tripping operations, the environment is harsh, and drilling mud and fluid can easily seep into the thread gaps of the top screw and the four-way body. After the liquid evaporates, impurities remain, which can cause the top screw to jam in subsequent operations, affecting equipment operation and increasing costs and safety risks.

[0003] High-pressure wellheads have extremely high sealing requirements, but the existing four-way valve body and top screw installation method have defects, lacking a suitable sealing structure, making it difficult to guarantee high sealing performance between the two. Furthermore, in complex environments, the top screw sealing assembly is prone to sealing failure, leading to oil and gas leaks and safety accidents. Therefore, there is an urgent need to develop a top screw sealing device with high sealing performance. Utility Model Content

[0004] The purpose of this utility model is to provide a wellhead top screw sealing device, which has good sealing performance and can ensure the sealing effect between the four-way body and the top screw.

[0005] To achieve the above objectives, this application provides a wellhead top screw sealing device, comprising: a four-way body, a top screw, a packing gland nut, and a sealing assembly.

[0006] Mounting holes are spaced apart on the periphery of the four-way body;

[0007] The mounting hole includes a first hole segment and a second hole segment connected in sequence. One end of the first hole segment penetrates the outer peripheral wall of the four-way body, and one end of the second hole segment penetrates the inner peripheral wall of the four-way body.

[0008] The set screw is inserted into the mounting hole, and the sealing component and the packing gland nut are sequentially sleeved on the outer periphery of the set screw. The sealing component is pressed by the packing gland nut onto the connecting end face of the first hole section and the second hole section.

[0009] The sealing assembly includes a sealing ring and an anti-compression ring and a retaining ring connected in sequence and respectively disposed at both ends of the sealing ring, wherein the anti-compression ring is closer to the sealing ring than the retaining ring.

[0010] As a preferred technical solution, the anti-extrusion ring has an annular groove on its end face facing the sealing ring, and the end face of the sealing ring has an annular boss that is adapted to and connected with the annular groove.

[0011] As a preferred technical solution, the cross-section of the annular groove is trapezoidal.

[0012] As a preferred technical solution, the contact end face between the anti-extrusion ring and the retaining ring is flat.

[0013] As a preferred technical solution, the sealing ring is made of polytetrafluoroethylene.

[0014] As a preferred technical solution, the anti-extrusion ring is a flexible component.

[0015] As a preferred technical solution, the anti-extrusion ring is a flexible metal part.

[0016] As a preferred technical solution, the retaining ring is a hard metal part.

[0017] As a preferred technical solution, the four-way body has multiple mounting holes spaced apart on its periphery, and multiple set screws are inserted into the mounting holes one by one.

[0018] The wellhead top screw sealing device provided by the above technical solution has the following advantages compared with the prior art: During assembly, the sealing component is first threaded onto the top screw, then the packing gland nut is tightened onto the top screw. The top screw is then inserted into the mounting hole on the four-way body, and the packing gland nut is gradually tightened to ensure a tight connection between it and the four-way body and the top screw. The sealing component is then compressed to ensure a tight fit between it and the four-way body and the top screw, thus completing the assembly. When it is necessary to remove the top screw, simply rotate the packing gland nut in the opposite direction to release the seal, allowing the top screw and sealing component to be unscrewed from the mounting hole. This application, by setting a sealing component and a packing gland nut consisting of a sealing ring and, sequentially, anti-compression rings and retaining rings located at both ends of the sealing ring, can achieve a tight connection between the top screw and the four-way body, ensuring good sealing performance between them. Attached Figure Description

[0019] The present application will be further described in detail below with reference to the accompanying drawings and preferred embodiments. However, those skilled in the art will appreciate that these drawings are drawn only for the purpose of explaining the preferred embodiments and therefore should not be construed as limiting the scope of the present application. Furthermore, unless specifically indicated, the drawings are intended only to conceptually represent the composition or structure of the described objects and may contain exaggerated representations, and the drawings are not necessarily drawn to scale.

[0020] Figure 1 This is a cross-sectional view of a wellhead top wire sealing device in the prior art;

[0021] Figure 2 This is a cross-sectional view of the wellhead top screw sealing device of this utility model;

[0022] Figure 3 This is a schematic diagram of part A of the present invention;

[0023] Figure 4 This is a cross-sectional view of the sealing assembly of this utility model;

[0024] Figure 5 This is a schematic diagram showing the disassembled sealing assembly of this utility model;

[0025] The components are: 1. Four-way body; 11. Mounting hole; 2. Set screw; 3. Sealing assembly; 31. Sealing ring; 310. Annular boss; 32. Anti-extrusion ring; 320. Annular groove; 33. Retaining ring; 4. Packing gland nut. Detailed Implementation

[0026] Preferred embodiments of this application will now be described in detail with reference to the accompanying drawings. Those skilled in the art will appreciate that these descriptions are merely descriptive and exemplary, and should not be construed as limiting the scope of protection of this application.

[0027] First, it should be noted that the directions such as top, bottom, upward, and downward mentioned in this article are defined relative to the directions in the various accompanying figures. They are relative concepts and therefore can change depending on their different positions and practical applications. Therefore, these or other directions should not be interpreted as restrictive terms.

[0028] It should be noted that the term "comprising" does not exclude other elements or steps, and "a" or "an" does not exclude the plural.

[0029] Furthermore, it should be noted that any single technical feature described or implied in the embodiments herein, or any single technical feature shown or implied in the accompanying drawings, can still be combined among these technical features (or their equivalents) to obtain other embodiments of this application not directly mentioned herein.

[0030] It should also be understood that while the terms "first," "second," etc., are used in this document to describe various types of information, this information should not be limited to these terms, which are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, "first" information may also be referred to as "second" information, and similarly, "second" information may also be referred to as "first" information.

[0031] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.

[0032] Please see Figure 2-4The wellhead top screw sealing device provided in this application embodiment includes: a four-way body 1, a top screw 2, a packing gland nut 4, and a sealing assembly 3.

[0033] Mounting holes 11 are spaced apart on the periphery of the four-way body 1;

[0034] The mounting hole 11 includes a first hole segment and a second hole segment connected in sequence. One end of the first hole segment passes through the outer peripheral wall of the four-way body 1, and one end of the second hole segment passes through the inner peripheral wall of the four-way body 1.

[0035] The set screw 2 is inserted into the mounting hole 11. The sealing component 3 and the packing gland nut 4 are sequentially sleeved on the outer periphery of the set screw, and the sealing component 3 is pressed by the packing gland nut 4 onto the connecting end face of the first hole section and the second hole section.

[0036] The sealing assembly 3 includes a sealing ring 31 and an anti-compression ring 32 and a retaining ring 33 connected in sequence and respectively disposed at both ends of the sealing ring 31. The anti-compression ring 32 is closer to the sealing ring 31 than the retaining ring 33.

[0037] In this embodiment, a sealing component 3 and a packing gland nut 4 are fitted on the set screw 2. The outer peripheral wall of the set screw 2 is provided with an external thread, and the packing gland nut 4 is screwed to the outer peripheral wall of the set screw 2. The sealing component 3 includes a sealing ring 31 and an anti-compression ring 32 and a retaining ring 33 connected in sequence and disposed at both ends of the sealing ring 31. The inner peripheral wall of the mounting hole 11 on the four-way body 1 is provided with an internal thread that matches the thread of the packing gland nut 4. During installation, the set screw 2 is first inserted into the mounting hole 11 on the four-way body 1. Then, the packing gland nut 4 is rotated, causing the retaining ring 33, anti-compression ring 32, and sealing ring 31 to be axially compressed and tightly connected together. The anti-compression ring 32 and sealing ring 31 deform and extend radially, making their inner walls tightly connected to the set screw 2 and their outer peripheral walls tightly connected to the four-way body 1, thus achieving a seal. As the packing gland nut 4 is continuously screwed in, the sealing effect gradually strengthens until the set screw 2 and the four-way body 1 are tightly connected together. This structure can greatly reduce the risk of leakage and seal failure during high-pressure wellhead operations, ensuring operational safety.

[0038] It is worth noting that the high precision and low deformation characteristics of the retaining ring 33 help improve the sealing performance of the entire sealing device and reduce the possibility of leakage. Furthermore, the retaining ring 33 ensures that the anti-compression ring 32 and the sealing ring 31 will not be axially extruded during compression deformation, thus guaranteeing the sealing effect.

[0039] Please see Figure 5In some embodiments, the anti-compression ring 32 has an annular groove 320 on its end face facing the sealing ring 31, and the end face of the sealing ring 31 has an annular boss 310 that is adapted to and engages with the annular groove 320. On one hand, the annular boss 310 can concentrate the contact area between the sealing ring 31 and the anti-compression ring 32. Under the pressure of the set screw 2, the annular boss 310 can generate greater contact pressure, thereby better compressing the sealing ring 31 and ensuring it fits tightly against the sealing surfaces of the set screw 2 and the four-way body 1, reducing leakage channels and improving sealing performance. On the other hand, the annular boss 310 has a guiding function, guiding the sealing ring 31 and the anti-compression ring 32 to accurately engage during installation, reducing installation difficulty and improving installation efficiency. During disassembly, the presence of the annular boss 310 makes it easier for the user to find the leverage point and more conveniently separate the sealing ring 31 and the anti-compression ring 32, reducing damage to components during disassembly.

[0040] It is worth noting that since the sealing surfaces of the sealing ring 31 and the anti-compression ring 32 are both smooth curved surfaces, it can be ensured that the sealing ring 31 and the anti-compression ring 32 will not scratch the set screw 2 during the axial movement of the set screw 2.

[0041] In some embodiments, the cross-section of the annular groove 320 is trapezoidal. The trapezoidal structure of the annular boss 310 provides better support and positioning, ensuring that the sealing ring 31 and the anti-compression ring 32 maintain a relatively accurate positional relationship during assembly and operation, preventing misalignment or displacement, and contributing to the structural stability of the entire sealing device. Furthermore, the trapezoidal annular boss 310 effectively and evenly transmits the pressure of the set screw 2 to the sealing ring 31, preventing excessive local deformation or damage to the sealing ring 31 due to uneven pressure distribution, thus extending the service life of the sealing ring 31.

[0042] In some embodiments, the contact end face between the anti-compression ring 32 and the retaining ring 33 is flat. The smooth and flat end face shape of the contact surface between the anti-compression ring 32 and the retaining ring 33 can ensure that it will not be squeezed out and fail when subjected to axial pressure, which is beneficial to enhancing the pressure resistance of both ends of the entire sealing assembly 3.

[0043] In some embodiments, the sealing ring 31 is made of polytetrafluoroethylene (PTFE). Firstly, PTFE has an extremely low coefficient of friction and good flexibility, allowing it to fit tightly against the surface of the sealing component, filling tiny gaps and uneven areas, effectively preventing leakage of high-pressure media and providing reliable sealing performance. Secondly, PTFE has excellent chemical stability, is almost unaffected by any chemical substances, and has strong resistance to corrosive media such as acids, alkalis, and salts that may be present in the high-pressure wellhead environment, maintaining sealing performance for a long time and extending the service life of the sealing device. Thirdly, PTFE maintains stable performance over a wide temperature range, withstanding the high temperatures generated during operation at the high-pressure wellhead, and is not prone to deformation, aging, or embrittlement, ensuring that the sealing ring 31 can still function normally in high-temperature environments. Fourthly, the smooth surface of PTFE makes it difficult for oil, dust, and other impurities to adhere, helping to keep the sealing ring 31 clean, preventing impurities from entering the sealing surface and affecting the sealing effect, and facilitating maintenance and cleaning.

[0044] In some embodiments, the anti-compression ring 32 is a flexible component. Utilizing its excellent ductility, the anti-compression ring 32 can increase its surface area when subjected to compression, allowing it to fit tightly against the set screw 2, the four-way body 1, and the sealing ring 31, further ensuring a sealing effect.

[0045] In some embodiments, the anti-extrusion ring 32 is a flexible metal component, specifically made of a low-hardness metal material such as copper. On one hand, copper has good flexibility and ductility, allowing the anti-extrusion ring 32 to fit more tightly against the outer peripheral wall of the top screw 2 and the inner peripheral wall of the four-way body 1 under the compression of the packing gland nut 4, filling tiny gaps and uneven areas, thereby effectively preventing leakage of high-pressure media and ensuring a sealing effect. On the other hand, during the operation of the high-pressure wellhead, the anti-extrusion ring 32 may rub and contact with components such as the top screw 2, the four-way body 1, and the sealing ring 31. Copper has relatively good wear resistance, which can reduce material loss and sealing performance degradation caused by friction, ensuring that the anti-extrusion ring 32 maintains good sealing function even after repeated use and long-term operation. Furthermore, the high-pressure wellhead generates a certain amount of heat during operation, and copper's good thermal conductivity helps to dissipate this heat quickly, avoiding performance degradation or damage to the sealing ring 31 due to localized overheating, thus contributing to maintaining the stability and reliability of the sealing device.

[0046] In some embodiments, the retaining ring 33 is a hard metal component, specifically made of high-hardness metal materials such as stainless steel and alloys. On one hand, during the operation of the wellhead equipment, the retaining ring 33 may rub and collide with other components. Materials such as stainless steel and alloys have good wear resistance, which can reduce wear, extend the service life of the retaining ring 33, and maintain the normal working condition of the sealing device. On the other hand, the environment at the wellhead is often harsh, containing various corrosive media. Stainless steel and alloys have excellent corrosion resistance, resisting the erosion of acids, alkalis, salts, and other substances, preventing the retaining ring 33 from being damaged by corrosion, and ensuring its long-term reliable operation in harsh environments. Furthermore, the hard metal retaining ring 33 can provide stable support for the anti-compression ring 32 and the sealing ring 31, enabling them to maintain a good sealing state under high pressure.

[0047] In some embodiments, the four-way body 1 has multiple mounting holes 11 spaced apart on its periphery, and multiple set screws 2 are inserted one-to-one into the mounting holes 11. By providing multiple mounting holes 11, multiple sealing components 3 can be installed on the four-way body 1 to achieve a better sealing effect, which is beneficial to further ensuring the safety and service life of the device during use.

[0048] In summary, the wellhead top screw sealing device provided in this embodiment uses a sealing component 3 and a packing gland nut 4 to tightly connect the top screw 2 and the four-way body 1, ensuring good sealing between the two and ensuring that the top screw 2 sealing device will not leak during use, thus ensuring safe use.

[0049] This specification discloses the present application with reference to the accompanying drawings and also enables those skilled in the art to implement the application, including making and using any device or system, employing suitable materials, and using any combination of methods. The scope of this application is defined by the claimed technical solution and includes other instances that would occur to those skilled in the art. Such other instances shall be considered to fall within the scope of protection defined by the claimed technical solution, provided that they include structural elements that are not different from the literal language of the claimed technical solution, or contain equivalent structural elements that are not substantially different from the literal language of the claimed technical solution.

Claims

1. A wellhead top screw sealing device, characterized in that, include: Four-way body, set screw, packing gland nut and sealing assembly. Mounting holes are spaced apart on the periphery of the four-way body; The mounting hole includes a first hole segment and a second hole segment connected in sequence. One end of the first hole segment penetrates the outer peripheral wall of the four-way body, and one end of the second hole segment penetrates the inner peripheral wall of the four-way body. The set screw is inserted into the mounting hole, and the sealing component and the packing gland nut are sequentially sleeved on the outer periphery of the set screw. The sealing component is pressed by the packing gland nut onto the connecting end face of the first hole section and the second hole section. The sealing assembly includes a sealing ring and an anti-compression ring and a retaining ring connected in sequence and respectively disposed at both ends of the sealing ring, wherein the anti-compression ring is closer to the sealing ring than the retaining ring.

2. The wellhead top screw sealing device according to claim 1, characterized in that, The anti-compression ring has an annular groove on its end face facing the sealing ring, and the end face of the sealing ring has an annular boss that is adapted to and connected with the annular groove.

3. The wellhead top screw sealing device according to claim 2, characterized in that, The cross-section of the annular groove is trapezoidal.

4. The wellhead top screw sealing device according to claim 3, characterized in that, The contact surface between the anti-compression ring and the retaining ring is flat.

5. The wellhead top screw sealing device according to any one of claims 1-4, characterized in that, The sealing ring is made of polytetrafluoroethylene.

6. The wellhead top screw sealing device according to claim 4, characterized in that, The anti-extrusion ring is a flexible component.

7. The wellhead top screw sealing device according to claim 6, characterized in that, The anti-extrusion ring is a flexible metal component.

8. The wellhead top screw sealing device according to claim 4, characterized in that, The retaining ring is a hard metal part.

9. The wellhead top screw sealing device according to claim 1, characterized in that, The four-way body has multiple mounting holes spaced apart on its periphery, and multiple set screws are inserted into the mounting holes one by one.

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