Composite type self-expansion packer

Abstract

The invention relates to a composite type self-expansion packer which comprises an expansion pipe body, and the two ends of the expansion pipe body are connected with connecting joints. And the self-expansion long rubber sleeve is attached to the peripheral wall of the expansion pipe body in a sleeving manner. Wherein the self-expansion long rubber sleeve is constructed to be composed of rubber of different rubber layers, and the expansion rates of the rubber of the different rubber layers are sequentially increased from outside to inside. According to the composite self-expansion packer, the sealing effect and the operation and use convenience can be improved, and it is guaranteed that the setting quality is qualified.

Description

Technical Field

[0001] The invention belongs to the field of oil and gas well development and production, and in particular relates to a composite self-expanding packer with an extra-large diameter for expansion screen pipe supplementation. Background Art

[0002] Commonly used packers include compression type, expansion type and self-expanding type. In actual use, both compression type and expansion type packers have some disadvantages: many supporting tools for setting seals need to be installed on the pipe string, and the tools are highly correlated, the operation risk is high, and the completion process is complex; the sealing elements have poor adaptability to irregular formations, and the interlayer isolation and sealing effect is poor; due to the limitations of the structure and sealing principle, the actual application validity period is short; the mechanical structure is complex and the diameter is small. Therefore, self-expanding packers are often used for long-term use.

[0003] At present, the self-expanding packers in the prior art also have shortcomings: in order to achieve the pressure resistance of the packer, strict requirements are placed on the annular space gap, the outer diameter of the sealing element is large, and it is difficult to lower it; the thickness of the sealing element has a great impact on the pressure bearing capacity of the packer, and the thick rubber layer affects the tool diameter. Summary of the invention

[0004] In order to solve all or part of the above problems, the present invention aims to provide a composite self-expanding packer with an extra-large diameter for supplementing an expandable screen pipe, so as to improve the sealing effect and the convenience of operation and use, so as to ensure the quality of the setting.

[0005] The present application provides a composite self-expanding packer, comprising: an expansion tube, with connecting joints connected to both ends of the expansion tube; and a self-expanding long rubber tube, which is attached and sleeved on the outer peripheral wall of the expansion tube. The self-expanding long rubber tube is constructed to be composed of rubber with different rubber layers, and the rubber with different rubber layers is constructed to have a larger expansion rate from the outside to the inside.

[0006] In some embodiments, the self-expanding long rubber tube includes a protective rubber layer arranged on the outer layer; a self-expanding main sealing rubber layer arranged on the middle layer; and a fast-expanding rubber layer arranged on the inner layer; the expansion rates of the fast-expanding rubber layer, the self-expanding main sealing rubber layer and the protective rubber layer become smaller in sequence.

[0007] In some embodiments, the expansion tube body includes a large diameter tube body portion located at both ends and a small diameter tube body portion located in the middle, and the rapid expansion rubber layer is at least attached to and wrapped around the small diameter tube body portion.

[0008] In some embodiments, the self-expanding long rubber tube is attached to and wrapped around the expansion tube.

[0009] In some embodiments, a plurality of annular grooves are formed on the outer peripheral wall of the cylinder body of the self-expanding long rubber cylinder at intervals along the axial direction.

[0010] In some embodiments, a radial cross-section of the annular groove is configured as a triangle.

[0011] In some embodiments, the self-expanding long rubber tube is formed on the outer peripheral wall of the expansion tube body by vulcanization molding.

[0012] In some embodiments, a compression-type sealing rubber cylinder is also included, and the compression-type sealing rubber cylinder is arranged in the middle part of the self-expanding long rubber cylinder in the axial direction.

[0013] In some embodiments, the compression-type sealing rubber cylinder includes a main rubber cylinder and end rubber cylinders symmetrically arranged on both sides of the main rubber cylinder, and the end rubber cylinders are connected to the self-expanding long rubber cylinder.

[0014] In some embodiments, the expansion pipe body is threadedly connected to the connection joint.

[0015] It can be seen from the above technical solution that the composite self-expanding packer provided by the present invention has the following advantages:

[0016] 1) The outer wall of the expansion tube is provided with a self-expanding long rubber tube, which automatically expands to fill the sealing space when in contact with oil or water, so that the self-expanding long rubber tube is closely attached to the well wall, so that the composite self-expanding packer has a good sealing effect;

[0017] 2) The self-expanding long rubber tube is divided into multiple layers from the outside to the inside. This structure can effectively enhance the pressure-bearing performance of the rubber tube, reduce the thickness of the rubber layer, optimize the expansion rate of the rubber tube, reduce the outer diameter of the tool while ensuring a good sealing effect;

[0018] 3) The self-expanding long rubber tube adopts a concave-convex structure, which can effectively retain the expansion medium such as oil and water in the annular groove, so that the self-expanding long rubber tube can fully contact with the oil or water to expand. At the same time, the annular groove always contains the expansion medium, which can increase the pressure resistance of the self-expanding long rubber tube;

[0019] 4) When the self-expanding long rubber tube expands under the oil-water medium, it also transmits the expansion force to the compression type sealing rubber tube. Under the double extrusion effect, the compression type sealing rubber tube plays an auxiliary sealing function and can buffer the damage of the self-expanding long rubber tube caused by pressure, further improving the sealing ability and service life of the composite self-expanding packer of the embodiment of the present invention;

[0020] 5) The composite self-expanding packer of the present invention combines the characteristics of the self-expanding packer and the expandable packer, and has a compact structure, a large diameter, a small outer diameter, and a wide range of applications;

[0021] 6) The composite self-expanding packer of the present invention adopts a symmetrical structural design and has no specific direction of use, making on-site operation convenient and safe. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of a composite self-expanding packer according to an embodiment of the present invention;

[0023] Figure 2 for Figure 1 The enlarged structural schematic diagram of the composite self-expanding packer is shown in FIG. DETAILED DESCRIPTION

[0024] In order to better understand the purpose, structure and function of the present invention, a composite self-expanding packer of the present invention is further described in detail below in conjunction with the accompanying drawings.

[0025] Figure 1 FIG. 2 shows the structure of a composite self-expanding packer 100 according to an embodiment of the present invention. Figure 1 As shown, the composite self-expanding packer 100 comprises: an expansion tube 1, with connecting joints 2 connected to both ends of the expansion tube 1; and a self-expanding long rubber tube 3, which is attached and sleeved on the outer peripheral wall of the expansion tube 1. The self-expanding long rubber tube 3 is constructed to be composed of rubber with different rubber layers, and the rubber with different rubber layers is constructed so that the expansion rate increases from the outside to the inside.

[0026] The composite self-expanding packer 100 in the present application can be used in series. In the present application, the expansion tube 1 can be expanded at the thin diameter of the expansion tube 1 under the action of the expansion cone to form a large diameter with a uniform inner diameter.

[0027] When the composite self-expanding packer 100 according to the embodiment of the present invention is used, multiple composite self-expanding packers 100 can be connected in series to the completion string. After being in place, the expansion tube body 1 expands at the thin diameter under the action of the expansion cone to form a large diameter with a uniform inner diameter. In this embodiment of the invention, the outer peripheral wall of the expansion tube body 1 is provided with a self-expanding long rubber tube 3. The self-expanding long rubber tube 3 contacts oil or water and will automatically expand to fill the sealing space after about 7-10 days, so that the self-expanding long rubber tube 3 is close to the well wall, so that the composite self-expanding packer 100 has a good sealing effect. At the same time, in this embodiment, the self-expanding long rubber tube 3 is divided into multiple layers from the outside to the inside, and the rubber of different rubber layers is constructed so that the expansion rate increases from the outside to the inside. With this structural design, the outer layer with a lower expansion rate can effectively enhance the pressure-bearing performance of the self-expanding long rubber tube 3, while the expansion rate of the inner layer increases successively, so that a good sealing effect can be guaranteed after rapid expansion. In addition, by designing a multi-layer structure, the thickness of the rubber layer of the self-expanding long rubber tube 3 can be reduced, thereby reducing the outer diameter of the tool.

[0028] Please refer to Figure 2In some embodiments, the self-inflating long rubber cylinder 3 may include a protective rubber layer 31 arranged on the outer layer; a self-inflating main sealing rubber layer 32 arranged on the middle layer; and a fast-expanding rubber layer 33 arranged on the inner layer; the expansion rates of the fast-expanding rubber layer 33, the self-inflating main sealing rubber layer 32 and the protective rubber layer 31 become smaller in sequence.

[0029] In the present application, the composite self-expanding packer 100 is lowered into the well. Under the action of the protective rubber layer 31 of the self-expanding long rubber tube 3, the expansion of the internal self-expanding main sealing rubber layer 32 can be effectively slowed down during the lowering process, so that the composite self-expanding packer 100 can be lowered smoothly. After being lowered to the target layer, the self-expanding long rubber tube 3 will automatically expand the rubber layer 33 and the self-expanding main sealing rubber layer 32 after encountering oil or water in the well for a period of time, so as to complete the sealing effect of the self-expanding long rubber tube 3.

[0030] Please go back Figure 1 In some embodiments, the expansion tube body 1 may include a large-diameter tube body portion 11 at both ends and a small-diameter tube body portion 12 in the middle, and the rapid expansion rubber layer 33 may at least be attached to and wrapped around the small-diameter tube body portion 12 .

[0031] In the present application, the expansion tube body 1 can expand at the small diameter of the expansion tube body 1 under the action of the expansion cone to form a large diameter with a uniform inner diameter. After the small diameter tube body portion 12 of the expansion tube body 1 is deformed, the rear supporting self-expanding long rubber tube 3 is further attached to the pipe column to ensure that the self-expanding long rubber tube 3 has a good sealing effect after expansion.

[0032] In some embodiments, the self-expanding long rubber tube 3 is attached to and wrapped around the expansion tube body 1 to increase the coverage area of ​​the self-expanding long rubber tube 3 and further improve the sealing effect after the self-expanding long rubber tube 3 expands.

[0033] Please combine Figure 1 and Figure 2 As shown, in some embodiments, a plurality of annular grooves 34 are formed on the outer peripheral wall of the cylinder body of the self-expanding long rubber cylinder 3 at intervals along the axial direction.

[0034] In this embodiment, the annular groove 34 makes the outer peripheral wall of the cylinder of the self-expanding long rubber cylinder 3 have a concave-convex structure. Through this setting, the self-expanding long rubber cylinder 3 adopts a concave-convex structure, and the expansion medium such as oil and water can be effectively retained in the annular groove 34, so that the self-expanding long rubber cylinder 3 can fully contact with the oil or water to expand. At the same time, the annular groove 34 always has the expansion medium, which can increase the pressure resistance of the self-expanding long rubber cylinder 3.

[0035] Please continue to refer to Figure 2 In some embodiments, the radial cross-section of the annular groove 34 may be configured as a triangle.

[0036] In this embodiment, the radial cross section of the annular groove 34 is a triangle. Of course, in other embodiments, the cross section may be other shapes. In the present application, the triangle can be understood as the annular groove 34 being directly connected by two side walls, which can facilitate the expansion and deformation of the self-expanding long rubber tube 3. At the same time, the triangle can also store expansion medium, which can increase the pressure resistance of the self-expanding long rubber tube 3.

[0037] In some embodiments, the self-expanding long rubber tube 3 can be formed on the outer peripheral wall of the expansion tube body 1 by vulcanization molding. Through this arrangement, the composite self-expanding packer 100 of the embodiment of the present invention has a stronger structural integrity, a compact overall structure, and a simple and reliable tool structure.

[0038] Please go back Figure 1 In some embodiments, the composite self-expanding packer 100 of the embodiment of the present invention may further include a compression-type sealing rubber tube 4 , which is disposed at the middle portion of the self-expanding long rubber tube 3 in the axial direction.

[0039] In this embodiment, the self-expanding long rubber cylinder 3 will also transfer the expansion force to the compression type sealing rubber cylinder 4 when it expands in the oil-water medium. At the same time, the compression type sealing rubber cylinder 4 will also expand in the oil-water medium. In this way, under the double extrusion effect, the compression type sealing rubber cylinder 4 expands and expands to play an auxiliary sealing function, and can buffer the damage of the self-expanding long rubber cylinder 3 caused by pressure, further improving the sealing ability and service life of the composite self-expanding packer 100 of the embodiment of the present invention.

[0040] Please continue to refer to Figure 1 In some embodiments, the compression type sealing rubber cylinder 4 may include a main rubber cylinder 41 and end rubber cylinders 42 symmetrically arranged on both sides of the main rubber cylinder 41 , and the end rubber cylinders 42 are connected to the self-expanding long rubber cylinder 3 .

[0041] Through the above arrangement, the composite self-expanding packer 100 of the embodiment of the present invention, on the one hand, combines the characteristics of the self-expanding packer 100 and the expandable packer, and the whole machine has a compact structure, a large diameter, a small outer diameter, and a wide range of applications; on the other hand, by arranging the compression type sealing rubber cylinder 4 at the middle part of the self-expanding long rubber cylinder 3 in the axial direction, the composite self-expanding packer 100 of the embodiment of the present invention adopts a symmetrical structural design, without a specific use direction, so that on-site operation is convenient and safe.

[0042] In some embodiments, the expansion pipe body 1 is threadedly connected to the connecting joint 2 to facilitate connection and use, further facilitating on-site operation.

[0043] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by those skilled in the art to which the present invention belongs.

[0044] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A composite self-expanding packer, characterized in that: include: An expansion pipe body, with connecting joints connected to both ends of the expansion pipe body; and, A self-expanding long rubber tube, which is attached and sleeved on the outer peripheral wall of the expansion tube body; The self-expanding long rubber tube is constructed to be composed of rubbers with different rubber layers, and the rubbers with different rubber layers are constructed such that the expansion rates increase successively from the outside to the inside.

2. The composite self-expanding packer according to claim 1, characterized in that: The self-expanding long rubber tube includes a protective rubber layer arranged on the outer layer; a self-expanding main sealing rubber layer arranged on the middle layer; and a fast-expanding rubber layer arranged on the inner layer; the expansion rates of the fast-expanding rubber layer, the self-expanding main sealing rubber layer and the protective rubber layer become smaller in sequence.

3. The composite self-expanding packer according to claim 2, characterized in that: The expansion tube body comprises a large-diameter tube body portion at both ends and a small-diameter tube body portion in the middle, and the rapid expansion rubber layer is at least attached to and wrapped around the small-diameter tube body portion.

4. The composite self-expanding packer according to claim 2, characterized in that: The self-expanding long rubber tube is attached and sleeved on and wrapped around the expansion tube body.

5. The composite self-expanding packer according to any one of claims 1 to 4, characterized in that: A plurality of annular grooves are formed on the outer peripheral wall of the cylinder body of the self-expanding long rubber cylinder at intervals along the axial direction.

6. The composite self-expanding packer according to claim 5, characterized in that: The radial cross section of the annular groove is configured as a triangle.

7. The composite self-expanding packer according to any one of claims 1 to 4, characterized in that: The self-expanding long rubber tube is formed on the outer peripheral wall of the expansion tube body by vulcanization molding.

8. The composite self-expanding packer according to any one of claims 1 to 4, characterized in that: It also includes a compression type sealing rubber cylinder, which is arranged at the middle part of the self-expanding long rubber cylinder in the axial direction.

9. The composite self-expanding packer according to claim 8, characterized in that: The compression type sealing rubber cylinder comprises a main rubber cylinder and end rubber cylinders symmetrically arranged on both sides of the main rubber cylinder, and the end rubber cylinders are connected to the self-expanding long rubber cylinder.

10. The composite self-expanding packer according to any one of claims 1 to 4, characterized in that: The expansion pipe body is threadedly connected to the connecting joint.

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