Recoverable packer

Abstract

The utility model discloses a recoverable packer which comprises a central pipe, an upper connector, a control sleeve, a rubber sleeve assembly and a lower connector are sequentially arranged on the central pipe in a sleeved mode, a forced recovery mechanism is arranged in the control sleeve, the control sleeve is fixedly connected with the rubber sleeve assembly, and the forced recovery mechanism is arranged on the side of the rubber sleeve assembly. The rubber can be forced to return to the initial state, the packer can be smoothly lifted out, normal work of the whole packer is guaranteed, effective sealing and anchoring functions can be achieved, and meanwhile the packer has the function of being completely retracted after unsealing.

Description

Technical Field

[0001] The utility model relates to the technical field of oilfield mining equipment, in particular to a recoverable packer. Background Art

[0002] In the fracturing and water injection processes of oil field exploitation, it is necessary to connect the packers in series to ensure the isolation of each layer for later construction operations. However, due to the deformation of the casing, the size of the tool will be limited. In the case of conventional small deformation, there are many types of tools to choose from, but once the casing deformation is too large, the plugging performance of the tool will play a decisive role in the construction. For example, the common casing is 5.5-inch casing, and with the middle and late stages of oil field exploitation, casing corrosion and formation collapse will cause serious casing necking deformation, which requires a small diameter and large deformation plugging tool to achieve the operation.

[0003] At present, the commonly used plugging tools include leather cup type, compression rubber cylinder type and expansion type plugging tools. When the leather cup type packer is used, it is inserted close to the inner wall of the casing, and its sealing mechanism is severely damaged. It can only withstand unidirectional pressure difference and has poor sealing performance.

[0004] The compression packer achieves deformation by squeezing the rubber. When faced with a large variable diameter casing, the mechanical properties of the rubber material are tested greatly. After long-term deformation, the rubber will form plastic deformation and cannot rebound.

[0005] The expansion type packer adopts hydraulic expansion and sealing, and its effective sealing distance is limited. It also needs to be fixed with an anchoring mechanism. When facing a large variable diameter casing, due to size limitations, the anchoring mechanism cannot provide effective anchoring, and the expansion ratio of the sealing mechanism is too large. Affected by the upper and lower pressure differences, it cannot meet the sealing function. Utility Model Content

[0006] In view of the above defects or shortcomings, the purpose of the utility model is to provide a recoverable packer.

[0007] In order to achieve the above purpose, the technical solution of the utility model is:

[0008] A recoverable packer is characterized by comprising: a central tube, on which an upper joint, a control sleeve, a rubber sleeve assembly, and a lower joint are sequentially sleeved, a forced recovery mechanism is arranged in the control sleeve, and the control sleeve is fixedly connected to the rubber sleeve assembly.

[0009] The control sleeve is mounted on the upper joint via shear pins.

[0010] The forced recovery mechanism comprises: a valve assembly installed in a control sleeve, a spring is installed on the valve assembly, one end of the spring is in contact with the valve assembly, and the other end of the spring is in contact with the control sleeve.

[0011] A valve seat is installed on the valve assembly.

[0012] A first supporting seal is installed between the valve assembly and the valve seat, and a second supporting seal and a fourth O-ring are installed between the valve assembly and the center pipe.

[0013] A second O-type sealing ring is installed between the valve seat and the central tube.

[0014] An upper rubber cylinder seat and a lower rubber cylinder seat are installed at both ends of the rubber cylinder assembly, the valve seat is installed on the upper rubber cylinder seat, and a third O-type sealing ring is installed between the upper rubber cylinder seat, the lower rubber cylinder seat and the rubber cylinder assembly.

[0015] A first O-type sealing ring is arranged between the central tube and the upper joint.

[0016] Compared with the prior art, the beneficial effects of the utility model are:

[0017] The utility model provides a recoverable packer. Since the compression packer is deformed by squeezing rubber, when facing a large variable diameter casing, the mechanical properties of the rubber material are tested greatly, and after a long period of deformation, the rubber will form plastic deformation and cannot rebound. The utility model arranges a forced recovery mechanism on the side of the rubber cylinder assembly, which can force the rubber to return to its initial state, and the packer can be smoothly pulled out, thereby ensuring the normal operation of the entire packer, and can achieve effective sealing and anchoring functions, and at the same time has the function of being able to be completely retracted after unsealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the recoverable packer of the utility model;

[0019] Figure 2 It is a structural schematic diagram of the forced recovery mechanism of the utility model.

[0020] In the figure, 1 is an upper joint; 2 is a center tube; 3 is a control sleeve; 4 is a valve seat; 5 is a valve assembly; 6 is an upper rubber cylinder seat; 7 is a rubber cylinder assembly; 8 is a lower rubber cylinder seat; 9 is a lower joint; 10 is a shear pin; 11 is a spring; 13 is a first supporting seal; 14 is a second supporting seal; 15 is a first O-ring; 16 is a second O-ring; 17 is a third O-ring; 18 is a fourth O-ring. DETAILED DESCRIPTION

[0021] The utility model will be described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the utility model.

[0022] like Figure 1 , 2 As shown, the utility model provides a recoverable sealer, comprising: a center pipe 2, on which an upper joint 1, a control sleeve 3, a rubber sleeve assembly 7, and a lower joint 9 are sequentially sleeved, a forced recovery mechanism is arranged in the control sleeve 3, the control sleeve 3 is fixedly connected to the rubber sleeve assembly 7, wherein the control sleeve 3 is installed on the upper joint 1 by a shear pin 10.

[0023] Specifically, the forced recovery mechanism includes: a valve assembly 5 installed in the control sleeve 3, a spring 11 is installed on the valve assembly 5, one end of the spring 11 is in contact with the valve assembly 5, and the other end is in contact with the control sleeve 3, and a valve seat 4 is installed on the valve assembly 5.

[0024] Preferably, a first supporting seal 13 is installed between the valve assembly 5 and the valve seat 4 , a second supporting seal 14 and a fourth O-ring 18 are installed between the valve assembly 5 and the center tube 2 ; and a second O-ring 16 is installed between the valve seat 4 and the center tube 2 .

[0025] An upper rubber cylinder seat 6 and a lower rubber cylinder seat 8 are installed at both ends of the rubber cylinder assembly 7, the valve seat 4 is installed on the upper rubber cylinder seat 6, a third O-ring 17 is installed between the upper rubber cylinder seat 6 and the lower rubber cylinder seat 8 and the rubber cylinder assembly 7, and a first O-ring 15 is arranged between the center tube 2 and the upper joint.

[0026] It should be noted that the rubber cylinder assembly 7 of the utility model uses a long-distance rubber cylinder, and a spiral pattern is processed on the outer surface of the rubber cylinder, which not only ensures the anchoring performance of the tool but also ensures the sealing performance of the tool, and also reduces the damage of the conventional slip teeth to the casing. When the packing operation is completed, only the pipe column needs to be lifted, and the packer can be unsealed. At the same time, in order to prevent the plastic deformation of the rubber caused by the long-term sealing of the packer, a forced recovery elastic device is designed at the lower end of the packer. The resilience of the strong spring forces the rubber to return to the initial state, thereby ensuring the safety of the tool.

[0027] This recoverable packer can smoothly pass through the large reducer with a small diameter. After passing through the reducer, when it needs to work, it only needs to pressurize the oil pipe. Under the sealing valve assembly mechanism, the liquid can only enter but cannot be discharged. The liquid is sealed in the mandrel and the annulus of the rubber tube, thereby realizing the product's isolation and anchoring functions; at this time, conventional production can be carried out. Once the pipe string needs to be raised, the soft anchor of the rubber causes the unsealing shear pin to cut off by lifting the pipe string, and the liquid sealed in the annulus of the mandrel and the rubber tube is released. Under the action of the rebound spring at the lower end, the rubber tube returns to its initial state, and the packer can be smoothly raised.

[0028] It is obvious to those skilled in the art that the above-mentioned specific examples are only preferred schemes of the present invention. Therefore, the improvements and changes that may be made by those skilled in the art to certain parts of the present invention still reflect the principles of the present invention and achieve the purpose of the present invention, and all belong to the scope of protection of the present invention.

Claims

1. A recoverable packer, characterized in that: include: A central tube (2), wherein an upper joint (1), a control sleeve (3), a rubber sleeve assembly (7), and a lower joint (9) are sequentially sleeved on the central tube (2), a forced recovery mechanism is arranged in the control sleeve (3), and the control sleeve (3) is fixedly connected to the rubber sleeve assembly (7).

2. The recoverable packer according to claim 1, characterized in that: The control sleeve (3) is mounted on the upper joint (1) via a shear pin (10).

3. The recoverable packer according to claim 1, characterized in that: The forced recovery mechanism comprises: a valve assembly (5) installed in a control sleeve (3); a spring (11) is installed on the valve assembly (5); one end of the spring (11) is in contact with the valve assembly (5) and the other end is in contact with the control sleeve (3).

4. The recoverable packer according to claim 3, characterized in that: A valve seat (4) is installed on the valve assembly (5).

5. The recoverable packer according to claim 4, characterized in that: A first supporting seal (13) is installed between the valve assembly (5) and the valve seat (4), and a second supporting seal (14) and a fourth O-ring (18) are installed between the valve assembly (5) and the center tube (2).

6. The recoverable packer according to claim 4 or 5, characterized in that: A second O-type sealing ring (16) is installed between the valve seat (4) and the central tube (2).

7. The recoverable packer according to claim 4, characterized in that: An upper rubber cylinder seat (6) and a lower rubber cylinder seat (8) are installed at both ends of the rubber cylinder assembly (7); the valve seat (4) is installed on the upper rubber cylinder seat (6); and a third O-type sealing ring (17) is installed between the upper rubber cylinder seat (6) and the lower rubber cylinder seat (8) and the rubber cylinder assembly (7).

8. The recoverable packer according to claim 1, characterized in that: A first O-type sealing ring (15) is provided between the central tube (2) and the upper joint.

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