Sealing structure of bridge plug

Abstract

The utility model discloses a sealing structure of a bridge plug, which comprises a central tube, a guide shoe arranged at the front end of the central tube, a slip, a connecting piece and a movable sleeve sequentially sleeved on the surface of the central tube in a direction far away from the guide shoe, and a rubber sleeve arranged between the connecting piece and the movable sleeve, an expansion ring made of a metal material is arranged on the outer side wall of the rubber sleeve in a surrounding manner; the expansion ring is made of red copper. The utility model has the following beneficial effects: the rubber sleeve is used for providing preliminary sealing and adaptability, and the metal expansion ring is used for providing extra supporting and sealing effects at high temperature. According to the structure, the elasticity of the rubber and the high-temperature resistance of the metal can be fully utilized, so that the sealing performance of the bridge plug in a high-temperature environment is improved, and the bridge plug can adapt to various irregular sleeve inner walls.

Description

Technical Field

[0001] The utility model relates to the technical field of oil and gas exploitation equipment, and more specifically, to a sealing structure of a bridge plug. Background Art

[0002] A bridge plug is a device used for segmented construction in segmented fracturing reconstruction. After it enters the construction position, it often needs to trigger its own slip mechanism through corresponding equipment, fix itself in the construction section by using slips, and further trigger the rubber cylinder to seal off, so as to play the role of segmented construction.

[0003] The existing sealing principle of bridge plugs generally uses rubber rubber cylinders. Due to the excellent elasticity of rubber, after being extruded, it can easily expand and become larger, contact the inner wall of the casing and achieve the sealing effect. However, in the case of high temperature, its sealing effect will be greatly reduced. Using only a metal expansion ring for sealing can ensure the sealing effect at high temperature, but its elasticity and deformation ability are relatively poor, and it is difficult to fully adapt to the irregularity of the inner wall of the casing, thus affecting the tightness of the seal. For example, a bridge plug sealing structure with the patent application number CN202220199263.X. During the process of setting the plug, it relies solely on the expansion of the metal expansion ring for sealing. The elasticity and deformation ability of the metal are relatively poor, and it is difficult to fully adapt to the irregularity of the inner wall of the casing, thereby affecting the subsequent sealing effect. Or, for example, an anti-backward bridge plug with the patent application number CN202320595233.5. During the working process of this device, when the temperature in the casing exceeds 120 degrees, the strength of the rubber rubber cylinder will decrease due to the influence of temperature increase, and its sealing performance will be greatly reduced. Summary of the Utility Model

[0004] An object of the utility model is to solve at least the above problems and / or defects and provide at least the advantages described hereinafter.

[0005] To achieve these objects and other advantages according to the utility model, a sealing structure of a bridge plug is provided, including: a central pipe, a guide shoe is arranged at the front end of the central pipe, a slip, a connecting piece and a movable sleeve are sequentially sleeved on the surface of the central pipe in a direction away from the guide shoe, and further including: a rubber cylinder arranged between the connecting piece and the movable sleeve, and a metal expansion ring is arranged around the outer side wall of the rubber cylinder;

[0006] Wherein, the material of the expansion ring is configured as copper.

[0007] Preferably, the surface of the rubber cylinder is configured as an arc structure, and the shape of the contact surface between the expansion ring and the rubber cylinder is matched.

[0008] Preferably, the slip is configured as an annular slip, and the annular slip is composed of a plurality of slip pieces arranged in the circumferential direction of the central pipe.

[0009] Preferably, the slips are configured as annular slips, and the annular slips are composed of a plurality of slip pieces in the circumferential direction of the central pipe.

[0010] Preferably, multiple circles of annular protrusions are provided on the surface of the slips;

[0011] Wherein, the longitudinal section of the annular protrusion is triangular, and the sizes of the multiple circles of annular protrusions increase in sequence along the direction away from the guide shoe.

[0012] The utility model has at least the following beneficial effects: The rubber cylinder is used to provide initial sealing and adaptability, while the metal expansion ring is used to provide additional support and sealing effect at high temperatures. This structure can make full use of the elasticity of rubber and the high-temperature resistance of metal, thereby improving the sealing performance of the bridge plug in high-temperature environments and adapting to various irregular inner walls of the casing.

[0013] Other advantages, objectives and features of the utility model will be partially reflected by the following description, and partially will also be understood by those skilled in the art through the research and practice of the utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic diagram of the overall structure of the utility model;

[0015] Figure 2 is a cross-sectional view of another structure of the rubber cylinder and the expansion ring.

[0016] Reference numerals in the drawings: 1, central pipe; 2, slips; 3, connecting piece; 4, movable sleeve; 5, rubber cylinder; 6, expansion ring; 7, slip pieces; 8, annular protrusions; 9, guide shoe. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] The following further detailed description of the utility model is made in conjunction with the drawings, so that those skilled in the art can implement it according to the description in the specification.

[0018] It should be understood that the terms such as "having", "comprising" and "including" used herein do not exclude the presence or addition of one or more other elements or their combinations.

[0019] It should be noted that in the description of the present utility model, the orientation or positional relationship indicated by the terms is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0020] In the description of the present utility model, unless otherwise clearly defined and limited, terms such as "installation", "provided with", "sheathed / connected", "connection", etc. shall be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium; it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0021] In addition, in the present utility model, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on the top of" the second feature can be that the first feature is directly above or obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "under the bottom of" the second feature can be that the first feature is directly below or obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than that of the second feature.

[0022] As Figure 1 shown, a sealing structure of a bridge plug includes: a central tube 1, a guide shoe 9 is provided at the front end of the central tube 1, a slip 2, a connecting member 3 and a movable sleeve 4 are sequentially sleeved along the surface of the central tube 1 in a direction away from the guide shoe 9, and further includes: a rubber cylinder 5 disposed between the connecting member 3 and the movable sleeve 4, and a swelling ring 6 made of a metal material is disposed around the outer side wall of the rubber cylinder 5;

[0023] Among them, the material of the swelling ring 6 is configured as copper.

[0024] Working principle:

[0025] The central tube 1 smoothly sends the bridge plug to the construction position through the guide shoe 9 provided at the bottom. The movable sleeve 4 is pushed by an external device to move towards the guide shoe 9, and the movable sleeve 4 pushes the rubber cylinder 5 to be compressed. At the same time, the swelling ring 6 above the rubber cylinder 5 deforms under the deformation and compression of the rubber cylinder 5 and contacts the inner wall of the casing. Under the action of the rubber cylinder 5 made of rubber material, the rubber cylinder 5 made of rubber material has excellent elasticity and deformation ability, enabling the swelling ring 6 made of metal material to closely fit with the inner wall of the casing. The tensile strength of copper is usually above 200 MPa, which is much higher than that of the rubber cylinder 5. Copper is soft in texture. After the swelling ring is extruded and expanded and deformed, the adhesion force with the inner wall of the casing is large. Through the elasticity of rubber and the high-temperature resistance characteristics of metal, the sealing performance of the bridge plug in a high-temperature environment is improved and it can adapt to various irregular inner walls of the casing.

[0026] In the above technical solution, the surface of the rubber cylinder 5 is configured as an arc structure, and the shape of the contact surface between the expansion ring 6 and the rubber cylinder 5 is matched. With this technical solution, the arc-shaped rubber cylinder 5 provides a certain shape support for the deformed expansion ring 6, ensuring that the expansion ring 6 can be in close contact with the inner wall of the casing.

[0027] In the above technical solution, the slip 2 is configured as an annular slip, and the annular slip is composed of a plurality of slip pieces 7 arranged in the circumferential direction of the central pipe 1. Adjacent two slip pieces 7 are connected by a connecting part (not shown), which not only ensures the stability of the connection between the slip pieces 7, but also enables the slip pieces 7 to expand outwards after being squeezed. The inclined surface of the connecting piece 3 faces the top of the central pipe 1 and extends into the space between the slip 2 and the central pipe 1. With this technical solution, during the process of the slip 2 expanding outwards under the extrusion of the movable plug and the connecting piece 3, each slip piece 7 is in close contact with the inner wall of the casing, improving the fixing effect of the bridge plug.

[0028] In the above technical solution, multiple circles of annular protrusions 8 are provided on the surface of the slip 2; among them, the longitudinal section of the annular protrusion 8 is triangular, and the sizes of the multiple circles of annular protrusions 8 increase in sequence along the direction away from the guide shoe 9. With this technical solution, the triangular structure has excellent stability and strength. When the slip 2 is pushed by the connecting piece 3, thereby causing each slip piece 7 to expand outwards, the triangular protrusions can better embed into the well wall, providing greater friction. The multiple circles of annular protrusions 8 increase in sequence, which can gradually increase the contact area and grip force with the well wall. As the slip 2 penetrates deeper, each larger circle of annular protrusion 8 will provide more support points, further enhancing the stability of the slip 2.

[0029] Although the embodiments of the present utility model have been disclosed above, it is not limited to only the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present utility model. For those familiar with the field, additional modifications can be easily achieved. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present utility model is not limited to the specific details and the illustrated and described examples here.

Claims

1. A sealing structure of a bridge plug, comprising: The central tube is provided with a guide shoe at its front end. A slip, a connecting piece, and a movable sleeve are sequentially sleeved on the surface of the central tube in a direction away from the guide shoe. It is characterized in that it further includes: a rubber cylinder arranged between the connecting piece and the movable sleeve, and a swelling ring made of a metal material is arranged around the outer side wall of the rubber cylinder; Among them, the material of the swelling ring is configured as copper.

2. The sealing structure of the bridge plug according to claim 1, characterized in that The surface of the rubber cylinder is configured as an arc structure, and the shape of the contact surface between the swelling ring and the rubber cylinder is matched.

3. The sealing structure of the bridge plug according to claim 1, characterized in that, The slip is configured as an annular slip, and the annular slip is composed of a plurality of slip pieces arranged in the circumferential direction of the central tube.

4. The sealing structure of the bridge plug according to claim 3, characterized in that, Multiple circles of annular protrusions are arranged on the surface of the slip; Among them, the longitudinal section of the annular protrusion is triangular, and the sizes of multiple circles of annular protrusions increase sequentially in a direction away from the guide shoe.

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