Anti-tear thin-wall seal for open hole wells

Abstract

The utility model relates to a kind of anti-tearing thin-wall sealing rubber tube for open hole, the sealing rubber tube, including rubber tube body, at least one group of retaining ring is equipped in rubber tube body inner wall, at least one group of outer hoop is equipped in rubber tube body outer wall shoulder part.Compression type operation is used in setting process, when axial pressure is applied, rubber tube body first extrusion expansion occurs, second retaining ring plays the role of centralizing and guiding, guarantee rubber tube body central section sealing ring zone uniform deformation and realize preliminary sealing;With the increase of pressure, rubber tube body upper and lower section gradually expand until contact well wall, drive first retaining ring and third retaining ring collaborative deformation, further enhance sealing and provide mechanical protection;Under extreme deformation condition, first outer hoop and second outer hoop can effectively limit the radial displacement of rubber tube body shoulder part, avoid tearing or failure of rubber tube body due to excessive deformation.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas field equipment technology, specifically to a tear-resistant thin-walled sealing sleeve for open-hole wells. Background Technology

[0002] With the continuous exploitation of oil and gas resources, the reliability and safety of downhole equipment are becoming increasingly important. During downhole drilling and production, packers are needed to seal and isolate the wellbore to control the flow of underground fluids and maintain pressure balance within the well.

[0003] A permanent packer typically consists of two parts: the packer itself and the permanent packer rubber seal assembly. The packer is usually made of metal and is used to isolate and restrict the flow of oil, gas, and water, thereby maintaining pressure balance within the well. The permanent packer rubber seal assembly is a crucial component for ensuring the packer's sealing performance.

[0004] Permanent packer rubber sealing assemblies can be designed and manufactured to meet various requirements and application environments. The core component is rubber, and its quality and performance directly affect the packer's sealing performance. Therefore, rubber sealing assemblies must possess high reliability, withstand harsh environments such as high temperatures, high pressures, and strong acids, and have the longest possible service life. Furthermore, the design and manufacture of permanent packer rubber sealing assemblies must also consider ease of installation and replacement.

[0005] In the manufacture of permanent packer rubber sealing components, high molecular materials such as high-quality ethylene propylene rubber and fluororubber are usually used. They have excellent heat resistance, oil resistance, acid and alkali resistance and corrosion resistance, which can ensure that the packer has excellent sealing performance and durability in complex downhole environments.

[0006] In summary, permanent packers and their rubber sealing components have significant application value in oil and gas extraction and downhole equipment. With the continuous advancement of petroleum industry technology, the technology and performance of permanent packers and their rubber sealing components will also be continuously improved, enhancing the reliability and safety of petroleum equipment. Utility Model Content

[0007] To address the above problems, this utility model provides a tear-resistant thin-walled sealing sleeve for open-hole wells, aiming to improve the safety and efficiency of sealing operations in open-hole sections.

[0008] The technical solution adopted by this utility model is: a tear-resistant thin-walled sealing rubber sleeve for open-hole wells, characterized in that: it includes a rubber sleeve body, the rubber sleeve body is an annular cylindrical structure, the inner wall of the rubber sleeve body is provided with at least one set of retaining rings, and the shoulder of the outer wall of the rubber sleeve body is provided with at least one set of outer hoop rings.

[0009] Preferably, the inner wall of the rubber tube body is provided with three circumferential inner grooves, namely a first circumferential inner groove at the upper end, a second circumferential inner groove at the middle, and a third circumferential inner groove at the lower end, wherein the first circumferential inner groove and the third circumferential inner groove are symmetrical to the second circumferential inner groove.

[0010] Preferably, a first retaining ring is provided in the first circumferential inner groove, a second retaining ring is provided in the second circumferential inner groove, and a third retaining ring is provided in the third circumferential inner groove.

[0011] Preferably, the outer wall of the rubber tube body is provided with two symmetrically arranged circumferential outward grooves, namely a first circumferential outward groove and a second circumferential outward groove. The first circumferential outward groove is disposed between the first circumferential inward groove and the second circumferential inward groove, and the second circumferential outward groove is disposed between the second circumferential inward groove and the third circumferential inward groove.

[0012] Preferably, a first outer ring is provided in the first circumferential outward groove, and a second outer ring is provided in the second circumferential outward groove.

[0013] Preferably, the material of the rubber sleeve body is one of nitrile rubber, hydrogenated nitrile rubber, fluororubber, AFLAS, or perfluoroether rubber.

[0014] Preferably, the retaining ring is made of one of the following materials: heat-resistant steel, wear-resistant steel, stainless steel, carbon steel, or nickel-based alloy.

[0015] Preferably, the outer ring is made of one of the following materials: heat-resistant steel, wear-resistant steel, stainless steel, carbon steel, or nickel-based alloy.

[0016] Preferably, the wellbore section with a single-sided annular space gap of not less than 10 mm can withstand a wellbore pressure of not less than 70 MPa.

[0017] As a preferred method, a compression operation is adopted during the actual setting process. When axial pressure is applied, the rubber sleeve first undergoes extrusion and expansion. The second retaining ring plays a role in straightening and guiding, ensuring that the sealing ring in the central section of the rubber sleeve deforms uniformly and achieves initial sealing. As the pressure increases, the upper and lower sections of the rubber sleeve gradually expand until they contact the well wall, causing the first and third retaining rings to deform in tandem, further enhancing the seal and providing mechanical protection. Under extreme deformation conditions, the first and second outer rings can effectively limit the radial displacement of the rubber sleeve shoulder, avoiding tearing or failure of the rubber sleeve due to excessive deformation.

[0018] The beneficial effects achieved by this utility model are: 1. Simplified structure and enhanced applicability: Traditional open-hole packer sleeves mostly adopt a two-component or three-component structure, which is difficult to meet the special requirements of large annulus thin-walled well sections; this patent application innovatively adopts a single sleeve design, which significantly reduces manufacturing complexity and cost, while improving the adaptability to large annulus open-hole sections, especially suitable for irregular wellbores and thin-walled annulus environments; 2. Deformation prevention and straightening mechanism: To solve the problem of irregular deformation of the rubber tube under axial pressure, this patent application sets end retaining rings (first retaining ring and third retaining ring) near both ends of the inner diameter of the rubber tube. This structure can provide effective straightening when the rubber tube is expanded under pressure, avoid skewing or twisting caused by the increase in length, and ensure that the sealing ring is uniform and reliable. 3. Anti-rupture and compression resistance: The outer shoulders of the rubber tube are equipped with outer rings (first outer ring and second outer ring), which can tightly restrain the shoulders of the rubber tube during expansion, limit its radial deformation, and prevent the rubber tube from tearing or breaking due to excessive expansion; this design significantly improves the structural integrity and sealing durability of the rubber tube under high pressure and large deformation conditions. 4. Excellent sealing performance: This structure can achieve a reliable sealing effect in both low-pressure and high-pressure environments, and is especially suitable for open-hole large annulus wells where thin-walled rubber sleeves are required; its sealing performance far exceeds that of traditional two-component and three-component elastomer rubber sleeves, effectively preventing leakage and sealing failure. 5. Wide adaptability to various working conditions and prevention of premature setting: This rubber sleeve assembly has good versatility and system compatibility. Its structural design can effectively avoid premature setting problems caused by friction or wellbore obstruction during the running process. At the same time, it maintains high pressure resistance and sealing stability in high temperature, high pressure and chemically corrosive media, significantly improving operational safety and reliability. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the rubber sleeve body of this utility model; Figure 2 This is a schematic diagram of the assembled rubber sleeve of this utility model; In the diagram: 1. Rubber tube; 11. First circumferential inward groove; 12. Second circumferential inward groove; 13. Third circumferential inward groove; 14. First circumferential outward groove; 15. Second circumferential outward groove; 21. First retaining ring; 22. Second retaining ring; 23. Third retaining ring; 31. First outer hoop; 32. Second outer hoop. Detailed Implementation

[0020] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0021] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0022] like Figure 1-2 As shown, this utility model discloses a tear-resistant thin-walled sealing sleeve for open-hole wells, comprising a sleeve body 1. The sleeve body 1 is a vertically penetrating, annular, thin-walled cylindrical structure, with metal reinforcing structures both inside and outside the sleeve body 1. The metal reinforcing structures are symmetrically arranged vertically along the middle of the sleeve body 1 and are separate assembly structures from the sleeve body 1 (i.e., the metal reinforcing structures and the sleeve body 1 are each independent parts). After assembly, the inner diameter of all metal parts of the metal reinforcing structures is consistent with the inner diameter of the sleeve body 1, and they are all fitted onto the mandrel.

[0023] The metal reinforcement structure consists of at least one set of retaining rings disposed on the inner wall of the rubber tube body 1 and at least one set of outer hoop rings disposed on the outer wall of the rubber tube body 1. The retaining rings are used to support the interior of the reinforced rubber tube body 1, and the outer hoop rings are used to support the exterior of the reinforced rubber tube body 1.

[0024] In this embodiment, the rubber sleeve body 1 can be made of one of the following polymer elastomer materials: nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), fluororubber (FKM), AFLAS®, or perfluoroether rubber (FFKM). The inner wall of the rubber sleeve body 1 has three concave structures: a first circumferential inner groove 11 at the upper end, a second circumferential inner groove 12 in the middle, and a third circumferential inner groove 13 at the lower end. The first circumferential inner groove 11 and the third circumferential inner groove 13 are symmetrically arranged with respect to the second circumferential inner groove 12.

[0025] The inner grooves at the upper and lower ends (the first circumferential inner groove 11 and the third circumferential inner groove 13) are of the same size and symmetrically distributed. They are used to install the first retaining ring 21 at the upper end and the third retaining ring 23 at the lower end, respectively, to adapt to the setting and sealing requirements under different well conditions.

[0026] The second circumferential inward groove 12 is located in the center of the rubber sleeve body 1 and is used to assemble the second retaining ring 22 in the middle. The second retaining ring 22 can promote the uniform expansion of the rubber sleeve body 1 under axial pressure, avoid local stress concentration, and thus ensure the integrity and consistency of the annular sealing surface.

[0027] The outer wall of the rubber tube body 1 is provided with an annular groove on the upper and lower shoulders, namely a first annular outward groove 14 and a second annular outward groove 15. The first annular outward groove 14 and the second annular outward groove 15 are symmetrically arranged on the outer wall of the rubber tube body 1. The first annular outward groove 14 is located between the first annular inward groove 11 and the second annular inward groove 12, and the second annular outward groove 15 is located between the second annular inward groove 12 and the third annular inward groove 13.

[0028] A first outer ring 31 is provided in the first outward groove 14, and a second outer ring 32 is provided in the second outward groove 15. This design is similar to a weightlifter's belt, which can provide effective radial restraint when the rubber sleeve body 1 undergoes large deformation and expansion, preventing the rubber sleeve body 1 from breaking due to excessive compression. This feature is particularly important in the working condition of sealing the large annular open section of the thin-walled structure.

[0029] In this embodiment, the retaining rings (first retaining ring 21, second retaining ring 22 and third retaining ring 23) are made of heat-resistant steel, wear-resistant steel, stainless steel, carbon steel or nickel-based alloy; the outer rings (first outer ring 31 and second outer ring 32) are made of heat-resistant steel, wear-resistant steel, stainless steel, carbon steel or nickel-based alloy (718 nickel alloy is used in highly corrosive environments).

[0030] The tear-resistant thin-walled sealing sleeve for open-hole wells of the present invention employs a compression operation during actual setting. When axial pressure is applied, the sleeve body 1 first undergoes extrusion and expansion. The second retaining ring 22 plays a role in straightening and guiding, ensuring uniform deformation of the sealing ring band in the central section of the sleeve body 1 and achieving initial sealing. As the pressure increases, the upper and lower sections of the sleeve body 1 gradually expand until they contact the well wall, causing the first retaining ring 21 and the third retaining ring 23 to deform in tandem, further enhancing the seal and providing mechanical protection. Under extreme deformation conditions, the first outer hoop ring 31 and the second outer hoop ring 32 can effectively limit the radial displacement of the sleeve shoulder, preventing the sleeve body 1 from tearing or failing due to excessive deformation.

[0031] The tear-resistant thin-walled sealing sleeve of this invention for open-hole wells can withstand a working pressure of 10,000 psi in open-hole sections with a single-sided annular gap of not less than 10 mm, exhibiting excellent sealing performance and anti-extrusion capability. Its overall structure has relatively relaxed material requirements, strong process feasibility, and good adaptability, effectively preventing premature setting and suitable for various casing specifications and severe well conditions.

[0032] It should be noted that the above description of the technical solutions is exemplary, and this specification may be embodied in different forms and should not be construed as limiting it to the technical solutions set forth herein. Rather, providing these descriptions will ensure that the disclosure of this utility model is thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Furthermore, the technical solutions of this utility model are defined only by the scope of the claims.

[0033] Finally, it should be noted that the above embodiments are merely representative examples of this utility model. Obviously, this utility model is not limited to the above embodiments and can have many variations. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this utility model should be considered to fall within the protection scope of this utility model.

Claims

1. A tear-resistant thin-walled sealing sleeve for open-hole wells, characterized in that: It includes a rubber tube body (1), which is an annular cylindrical structure. The inner wall of the rubber tube body (1) is provided with at least one set of retaining rings, and the upper and lower shoulders of the outer wall of the rubber tube body (1) are provided with at least one set of outer hoop rings.

2. The tear-resistant thin-walled sealing sleeve for open-hole wells according to claim 1, characterized in that: The inner wall of the rubber tube body (1) is provided with three circumferential inner grooves, namely a first circumferential inner groove (11) at the upper end, a second circumferential inner groove (12) in the middle and a third circumferential inner groove (13) at the lower end. The first circumferential inner groove (11) and the third circumferential inner groove (13) are symmetrical to the second circumferential inner groove (12).

3. The tear-resistant thin-walled sealing sleeve for open-hole wells according to claim 2, characterized in that: The first circumferential inward groove (11) is provided with a first retaining ring (21), the second circumferential inward groove (12) is provided with a second retaining ring (22), and the third circumferential inward groove (13) is provided with a third retaining ring (23).

4. The tear-resistant thin-walled sealing sleeve for open-hole wells according to claim 2, characterized in that: The outer wall of the rubber tube body (1) is provided with two symmetrically arranged circumferential grooves, namely a first circumferential groove (14) and a second circumferential groove (15). The first circumferential groove (14) is located between the first circumferential groove (11) and the second circumferential groove (12), and the second circumferential groove (15) is located between the second circumferential groove (12) and the third circumferential groove (13).

5. The tear-resistant thin-walled sealing sleeve for open-hole wells according to claim 4, characterized in that: The first circumferential groove (14) is provided with a first outer ring (31), and the second circumferential groove (15) is provided with a second outer ring (32).

6. A tear-resistant thin-walled sealing sleeve for open-hole wells according to claim 1, characterized in that: The material of the rubber sleeve body (1) is one of nitrile rubber, hydrogenated nitrile rubber, fluororubber, AFLAS or perfluoroether rubber.

7. A tear-resistant thin-walled sealing sleeve for open-hole wells according to claim 1, characterized in that: The retaining ring is made of one of the following materials: heat-resistant steel, wear-resistant steel, stainless steel, carbon steel, or nickel-based alloy.

8. The tear-resistant thin-walled sealing sleeve for open-hole wells according to claim 1, characterized in that: The outer ring is made of one of the following materials: heat-resistant steel, wear-resistant steel, stainless steel, carbon steel, or nickel-based alloy.

9. The tear-resistant thin-walled sealing sleeve for open-hole wells according to claim 1, characterized in that: It withstands a wellbore pressure of not less than 70 MPa in an open hole section with a single-sided annular space gap of not less than 10 mm.

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