Check valve of electric submersible pump

Abstract

The utility model relates to an electric submersible pump check valve which comprises a check valve body (1), a first cavity (2) and a second cavity (3) are arranged in the check valve body (1), and the inner diameter of the first cavity (2) is larger than that of the second cavity (3). The centralizing and limiting structure (4) is arranged in the first cavity (2); the sealing ball structure (5) is arranged in the first cavity (2), one end of the sealing ball structure (5) is elastically connected with the centralizing and limiting structure (4), and the other end of the sealing ball structure (5) opens and closes an opening, facing the first cavity (2), of the second cavity (3); and the centralizing and limiting structure (4) limits the axial reciprocating motion of the sealing ball structure (5) along the check valve body (1). The check valve solves the problem that a traditional check valve cannot effectively prevent well fluid from flowing back in a highly-deviated oil well, and can ensure the use effectiveness of the check valve of an electric submersible pump well in the highly-deviated oil well, so that an electric submersible pump is protected; and the problem of pipe leakage of a highly-deviated well due to the fact that the check valve is not reset is also solved.

Description

Technical Field

[0001] The utility model relates to the technical field of oil production equipment, in particular to a submersible electric pump check valve. Background Art

[0002] Horizontal wells and highly deviated oil wells are effective means for the oil extraction industry to effectively increase production and improve the ultimate recovery rate of oil and gas, and are also the main development direction of oil and gas reservoir development in the future. Some oil fields are affected by special landforms (such as reservoirs, villages, etc.), and when they are developed, they need to be developed using highly deviated wells or horizontal wells. In the process of marine oil and gas extraction, due to the limitations of offshore oil production equipment, the wellhead location must be concentrated in a very small area of ​​the oil production platform. However, in order to increase the reservoir range of oil wells, inclined wells, highly deviated wells, and horizontal wells are generally used for development. In addition, many platforms without drilling and repair machines have dual electric pump production strings lowered to extend the production life of oil wells.

[0003] The ball or plate of a conventional submersible electric pump check valve is seated on the valve seat by gravity. When this type of check valve is used in highly deviated oil wells or horizontal wells, part of the weight of the ball or plate will act on the inner wall of the valve body and cannot effectively fall back to the valve seat, thus affecting the normal use of the check valve in highly deviated oil wells. For dual electric pump wells, the check valve of the non-operating electric pump often fails to reset, causing tubing leakage, reduced production, or even no production. Utility Model Content

[0004] The utility model aims to solve at least one technical problem in the background technology and provides a submersible electric pump check valve.

[0005] In order to achieve the above object, the utility model provides a submersible electric pump check valve, comprising:

[0006] A check valve body, wherein a first cavity and a second cavity are provided inside the check valve body, wherein the inner diameter of the first cavity is larger than the inner diameter of the second cavity;

[0007] A righting and limiting structure is arranged in the first cavity;

[0008] A sealing ball structure is disposed in the first cavity, one end of which is elastically connected to the righting and limiting structure, and the other end of which opens and closes the opening of the second cavity facing the first cavity;

[0009] The straightening and limiting structure limits the sealing ball structure from reciprocating along the axial direction of the check valve body.

[0010] According to one aspect of the utility model, an inner wall of one end of the first cavity away from the second cavity is provided with an internal thread, and an outer wall of the second cavity away from the first cavity is provided with an external thread.

[0011] According to one aspect of the utility model, the straightening and limiting structure comprises: a straightening plate, a limiting plate and a return spring;

[0012] The centralizing plate and the inner wall of the first cavity are installed in the first cavity perpendicularly to each other;

[0013] The limit plate is arranged along the axial direction of the check valve body, one end of which is installed at the middle position of the centralizing plate, and the other end of which extends toward the direction of the second cavity;

[0014] A mounting groove is provided in the limiting plate, and the opening of the mounting groove faces the second cavity;

[0015] The return spring is arranged in the mounting groove.

[0016] According to one aspect of the utility model, the centralizing plate comprises a first centralizing plate and a second centralizing plate, and the first centralizing plate and the second centralizing plate are installed perpendicularly to each other in the first cavity.

[0017] According to one aspect of the utility model, the sealing ball structure comprises: a sealing ball and a ball handle;

[0018] One end of the ball handle extends into the mounting slot and is connected to the return spring;

[0019] One side of the sealing ball is connected to the other end of the ball handle, and the other side opens and closes the opening of the second cavity under the action of the return spring.

[0020] According to one solution of the utility model, a submersible electric pump check valve comprises: a check valve body, a first cavity and a second cavity are provided inside, the inner diameter of the first cavity is larger than the inner diameter of the second cavity; a righting and limiting structure is arranged in the first cavity; a sealing ball structure is arranged in the first cavity, one end of which is elastically connected to the righting and limiting structure, and the other end opens and closes the opening of the second cavity facing the first cavity (i.e., the valve seat); the righting and limiting structure limits the sealing ball structure to move back and forth along the axial direction of the check valve body. In this way, the righting and limiting structure can limit the sealing ball structure, on the one hand, limit the sealing ball structure to reciprocate only in the axial direction inside the check valve body, ensure that the sealing ball structure will not act on the inner wall of the check valve body due to gravity when applied to a highly deviated oil well or a horizontal well, ensure that the sealing ball structure will not have a posture deviation, and ensure that it can effectively fall back to the opening of the second cavity facing the first cavity to form an effective seal; on the other hand, limit the axial movement stroke of the sealing ball structure, ensure that the axial movement stroke of the sealing ball structure is controllable, and ensure the opening and closing accuracy.

[0021] According to one scheme of the utility model, the straightening and limiting structure includes: a straightening plate, a limiting plate and a reset spring; the straightening plate and the inner wall of the first cavity are installed in the first cavity perpendicularly to each other; the limiting plate is arranged along the axial direction of the check valve body, one end of which is installed in the middle position of the straightening plate, and the other end extends in the direction of the second cavity; a mounting groove is provided in the limiting plate, the opening of the mounting groove faces the second cavity, and the side away from the second cavity is sealed; the reset spring is arranged in the mounting groove. In this way, the straightening plate can form a basic support, ensure that the position of the limiting plate installed on the straightening plate is stable and reliable, and can maintain the position accuracy, ensure that the limiting plate is arranged along the internal axial center line of the check valve body, and ensure the accuracy of the sealing ball structure connected to the straightening and limiting structure in opening and closing the opening of the second cavity facing the first cavity.

[0022] According to one solution of the utility model, the centralizing plate includes a first centralizing plate and a second centralizing plate, and the first centralizing plate and the second centralizing plate are installed perpendicularly to each other in the first cavity. The first centralizing plate and the second centralizing plate are detachably supported on the inner wall of the first cavity by a retaining spring. In this way, the centralizing plate can be installed stably in the first cavity, the supporting strength can be ensured, and the centralizing plate can be disassembled as needed to repair or replace the relevant components.

[0023] According to one scheme of the utility model, the sealing ball structure includes: a sealing ball and a ball handle; one end of the ball handle extends into the mounting groove and is connected to the reset spring; one side of the sealing ball is connected to the other end of the ball handle, and the other side opens and closes the opening of the second cavity under the action of the reset spring. With such a configuration, the reset spring can be placed through the mounting groove, the ball handle can be straightened, and a moving channel can be provided for the ball handle, so as to ensure the purpose of the reset spring applying an effective force to the ball handle. A ball handle is provided on the sealing ball, and the ball handle is placed in the mounting groove and can move along the mounting groove. When the sealing ball is located at the opening of the second cavity, the reset spring is in a compressed state, and a certain downward force is applied to the ball handle. When the oil well is in normal production, the sealing ball moves upward and leaves the valve seat under the action of the fluid, and at this time, the reset spring is further compressed. When the submersible electric pump stops pumping, the sealing ball quickly sits on the valve seat under the action of the reset spring force and the vertical component of gravity, thereby closing the check valve. When the submersible pump starts production, the oil and gas are pressurized by the submersible pump and lifted upward, pushing open the sealing ball. The ball handle further compresses the spring, causing the sealing ball to leave the valve seat and the fluid flow channel to open, thereby ensuring normal production of the oil well.

[0024] According to the solution of the utility model, the utility model provides a submersible electric pump check valve suitable for highly deviated wells or horizontal wells, which can solve the problem that the valve ball of a traditional submersible electric pump check valve cannot fall back to the valve seat normally in highly deviated oil wells or horizontal wells, and can ensure the reliability of the check valve in highly deviated oil wells or horizontal wells, and can effectively avoid the problem of tubing loss in dual electric pump wells caused by the failure to reset the check valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A cross-sectional view schematically showing a submersible electric pump check valve according to an embodiment of the utility model;

[0026] Figure 2 The figure schematically shows a top view of a submersible electric pump check valve according to an embodiment of the utility model. DETAILED DESCRIPTION

[0027] The present invention will now be discussed with reference to exemplary embodiments. It should be understood that the embodiments discussed are only intended to enable those skilled in the art to better understand and implement the present invention, rather than to imply any limitation on the scope of the present invention.

[0028] As used herein, the term “including” and variations thereof are to be interpreted as open-ended terms meaning “including, but not limited to.” The term “based on” is to be interpreted as “based, at least in part, on.” The terms “one embodiment” and “an embodiment” are to be interpreted as “at least one embodiment.”

[0029] Figure 1 The cross-sectional view of a submersible electric pump check valve according to an embodiment of the utility model is schematically shown. Figure 1 As shown, in this embodiment, the submersible electric pump check valve includes:

[0030] The check valve body 1 has a first cavity 2 and a second cavity 3 inside, and the inner diameter of the first cavity 2 is larger than the inner diameter of the second cavity 3;

[0031] The righting and limiting structure 4 is arranged in the first cavity 2;

[0032] The sealing ball structure 5 is arranged in the first cavity 2, one end of which is elastically connected to the righting and limiting structure 4, and the other end of which opens and closes the opening of the second cavity 3 facing the first cavity 2 (i.e., the valve seat mentioned above);

[0033] The righting and limiting structure 4 limits the axial reciprocating movement of the sealing ball structure 5 along the one-way valve body 1. With such a configuration, the righting and limiting structure 4 can limit the sealing ball structure 5. On the one hand, the sealing ball structure 5 is limited to reciprocating in the axial direction inside the one-way valve body 1, ensuring that when the sealing ball structure 5 is applied to a highly deviated oil well or a horizontal well, it will not act on the inner wall of the one-way valve body 1 due to gravity problems, ensuring that the sealing ball structure 5 will not have a posture deviation, ensuring that it can effectively fall back to the opening of the second cavity 3 facing the first cavity 2 to form an effective seal; on the other hand, the axial movement stroke of the sealing ball structure 5 is limited, ensuring that the axial movement stroke of the sealing ball structure 5 is controllable, and ensuring the opening and closing accuracy.

[0034] Furthermore, if Figure 1 As shown, in this embodiment, an internal thread 6 is provided on the inner wall of one end of the first cavity 2 away from the second cavity 3, and an external thread 7 is provided on the outer wall of the second cavity 3 away from the first cavity 2. In this way, the internal thread 6 and the external thread 7 can be connected to the upper oil pipe and the lower oil pipe in the oil production string respectively, so that the submersible electric pump check valve of the utility model can be used as a component in the oil production string.

[0035] Furthermore, if Figure 1 As shown, in this embodiment, the straightening and limiting structure 4 includes: a straightening plate 8, a limiting plate 9 and a return spring 10;

[0036] The centralizing plate 8 and the inner wall of the first cavity 2 are installed in the first cavity 2 perpendicularly to each other;

[0037] The limit plate 9 is arranged along the axial direction of the check valve body 1, one end of which is installed in the middle position of the straightening plate 8, and the other end extends toward the direction of the second cavity 3;

[0038] A mounting groove 11 is provided in the limiting plate 9, the opening of the mounting groove 11 faces the second cavity 3, and the side away from the second cavity 3 is sealed;

[0039] The return spring 10 is arranged in the installation groove 11. In this way, the basic support can be formed by the straightening plate 8, so that the position of the limit plate 9 installed on the straightening plate 8 is stable and reliable, and the position accuracy can be maintained, so that the limit plate 9 is arranged along the inner axial center line of the check valve body 1, and the sealing ball structure 5 connected to the straightening limit structure 4 can open and close the opening of the second cavity 3 facing the first cavity 2 with accuracy.

[0040] Further, Figure 2 The following schematically shows a top view of a submersible electric pump check valve according to an embodiment of the present utility model. Figure 1 and Figure 2As shown, in this embodiment, the centralizing plate 8 includes a first centralizing plate 14 and a second centralizing plate 15, and the first centralizing plate 14 and the second centralizing plate 15 are installed perpendicularly to each other in the first cavity 2. In this embodiment, the first centralizing plate 14 and the second centralizing plate 15 are detachably supported on the inner wall of the first cavity 2 by a clamping spring 16. Such a configuration can ensure the installation stability of the centralizing plate 8 in the first cavity 2 and the support strength, and the centralizing plate 8 can be disassembled as needed and then the relevant components can be repaired or replaced.

[0041] Furthermore, if Figure 1 As shown, in this embodiment, the sealing ball structure 5 includes: a sealing ball 12 and a ball handle 13;

[0042] One end of the ball handle 13 extends into the mounting groove 11 and is connected to the return spring 10;

[0043] One side of the sealing ball 12 is connected to the other end of the ball handle 13, and the other side opens and closes the opening of the second cavity 3 under the action of the reset spring 10. With such a configuration, the reset spring 10 can be placed through the mounting groove 11, the ball handle 13 can be straightened, and a moving channel can be provided for the ball handle 13, so as to ensure that the reset spring 10 applies an effective force to the ball handle 13. The ball handle 13 is provided on the sealing ball 12, and the ball handle is placed in the mounting groove 11 and can move along the mounting groove 11. When the sealing ball 12 is located at the opening of the second cavity, the reset spring 10 is in a compressed state, and a certain downward force is applied to the ball handle 13. When the oil well is in normal production, the sealing ball 12 moves upward and leaves the valve seat under the action of the fluid, and at this time, the reset spring 10 is further compressed. When the submersible electric pump stops pumping, the sealing ball 12 is quickly seated on the valve seat under the action of the reset spring 10 and the vertical component of gravity, so as to close the check valve. When the submersible pump starts production, the oil and gas are pressurized by the submersible pump and lifted upward, pushing open the sealing ball 12. The ball handle 13 further compresses the spring, the sealing ball 12 leaves the valve seat, and the fluid flow channel is opened, thereby ensuring the normal production of the oil well.

[0044] According to the above scheme of the utility model, during installation, the sealing ball 12 is first placed on the valve seat, the reset spring 10 is placed in the installation groove 11, the installation groove 11 and the straightening plate 8 are placed in the check valve body 1, the ball handle 13 is inserted into the installation groove 11, and the straightening plate 8 is continuously lowered, the reset spring 10 is compressed, until the straightening plate 8 reaches the position of the retaining spring 16 and is fixed by the retaining spring 16, and the installation is completed. After the installation of the submersible electric pump check valve of the utility model is completed, it is connected to the production string of the submersible electric pump well through the upper internal thread 6 and the lower external thread 7, and normal use can be achieved.

[0045] According to the above scheme of the utility model, when it is necessary to replace the return spring 10 or the sealing ball 12, the retaining spring 16 is loosened, the straightening plate 8 and the limit plate 9 are taken out, and the return spring 10 or the sealing ball 12 can be replaced.

[0046] According to the above scheme of the utility model, the utility model provides a submersible electric pump check valve suitable for highly deviated wells or horizontal wells, which can solve the problem that the valve ball of a traditional submersible electric pump check valve cannot fall back to the valve seat normally in highly deviated oil wells or horizontal wells, and can ensure the reliability of the check valve in highly deviated oil wells or horizontal wells, and can effectively avoid the problem of tubing loss in dual electric pump wells caused by the failure to reset the check valve.

[0047] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the utility model.

Claims

1. Submersible electric pump check valve, characterized in that: include: A check valve body (1) is provided with a first cavity (2) and a second cavity (3) inside, wherein the inner diameter of the first cavity (2) is greater than the inner diameter of the second cavity (3); A righting and limiting structure (4) is arranged in the first cavity (2); A sealing ball structure (5) is arranged in the first cavity (2), one end of which is elastically connected to the righting and limiting structure (4), and the other end of which opens and closes an opening of the second cavity (3) facing the first cavity (2); The righting and limiting structure (4) limits the sealing ball structure (5) from moving back and forth along the axial direction of the check valve body (1); The straightening and limiting structure (4) comprises: a straightening plate (8), a limiting plate (9) and a return spring (10); The centralizing plate (8) and the inner wall of the first cavity (2) are installed in the first cavity (2) perpendicularly to each other; The limit plate (9) is arranged along the axial direction of the check valve body (1), one end of which is installed at the middle position of the centralizing plate (8), and the other end of which extends in the direction of the second cavity (3); The limiting plate (9) is provided with a mounting groove (11), and the opening of the mounting groove (11) faces the second cavity (3); The return spring (10) is arranged in the installation groove (11).

2. The submersible electric pump check valve according to claim 1, characterized in that: An internal thread (6) is provided on the inner wall of one end of the first cavity (2) away from the second cavity (3), and an external thread (7) is provided on the outer wall of the second cavity (3) away from the first cavity (2).

3. The submersible electric pump check valve according to claim 1, characterized in that: The centralizing plate (8) comprises a first centralizing plate and a second centralizing plate, and the first centralizing plate and the second centralizing plate are installed perpendicularly to each other in the first cavity (2).

4. The submersible electric pump check valve according to claim 1 or 3, characterized in that: The sealing ball structure (5) comprises: a sealing ball (12) and a ball handle (13); One end of the ball handle (13) extends into the mounting groove (11) and is connected to the return spring (10); One side of the sealing ball (12) is connected to the other end of the ball handle (13), and the other side opens and closes the opening of the second cavity (3) under the action of the return spring (10).

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