Mechanical gas lift valve

Abstract

The utility model discloses a mechanical gas lift valve which comprises a gas lift valve body, a valve seat is arranged in the gas lift valve body, a valve rod is arranged above the valve seat in the gas lift valve body, the valve rod is provided with a force transmission ring, the force transmission ring and the gas lift valve body are sealed, and the gas lift valve body is provided with a gas injection hole between the valve seat and the force transmission ring. The upper end of the gas lift valve body is connected with a valve rod reset mechanism; the upper end of the reset mechanism is connected with the pressure loading mechanism; the valve rod penetrates through the valve rod resetting mechanism and is inserted into the pressure loading mechanism; the valve rod blocks the valve seat under the action of the reset mechanism. When the device is used, on-site staff can set opening pressure on site according to design requirements, special equipment and professional personnel are not needed to set the opening pressure, the device is convenient and fast to use and can be repeatedly used, on-site construction efficiency is greatly improved, and crude oil development cost is reduced.

Description

Technical Field

[0001] This utility model relates to the field of air lift valve technology, specifically a mechanical air lift valve. Background Technology

[0002] Nitrogen-stage wellbore drainage technology is increasingly used in oilfield workover operations such as clearing oil reservoir blockages, fracturing fluid backflow, residual acid backflow, and creating negative pressure in the wellbore. The gas lift valve is one of the key tools in this process. Currently, commonly used gas lift valves typically operate by filling with nitrogen, and the pressure level is set by controlling the filling pressure. After each operation, specialized equipment is needed to adjust the filling pressure, which cannot meet the requirements for rapid workover operations.

[0003] Announcement No. CN212508237U discloses a pilot-operated air lift valve. When the air pressure input through the side through-hole is greater than the set pressure, the gas in the side through-hole passes through the damping hole, the upper connecting hole, the right cavity, and the inner cavity of the control valve seat in sequence, opening the control valve needle. The gas enters the right cavity, then passes through the inner cavity of the control valve body, the central hole, the inner cavity of the main valve seat, and the lower through-hole, entering the inner cavity of the connector, pushing the single-flow valve core downward to open. Due to the effect of the damping hole, a pressure difference is formed between the upper and lower surfaces of the main valve core. The main valve core moves upward, opening the main valve core and the main valve seat. The fluid flows along the inner cavity of the main valve seat and the single-flow valve, and finally enters the working cylinder below from the lower outlet.

[0004] The existing technology has a complex structure and contains microchannels, which are easily blocked by solid impurities in the well, making it unsuitable for long-term use.

[0005] Publication No. CN218062275U discloses a high / low pressure switchable air lift valve, including a first valve body unit and a second valve body unit. The first valve body unit includes a valve mechanism, a first chamber and a second chamber separated by the valve mechanism, and a valve seat disposed in the second chamber. The second chamber has a first through hole. In the initial state, the first end of the valve mechanism forms a seal with one end of the valve seat, while the second end extends from the other end of the valve seat. The second valve body unit includes a third chamber. The valve mechanism is configured to change position according to the pressure difference between the first and second chambers, allowing the second chamber to selectively communicate with the third chamber through a valve hole in the valve seat.

[0006] The existing technology controls the opening pressure by setting the pressure of the pressure chamber. Inflation and depressurization require specialized pressure control equipment, which results in low work efficiency.

[0007] Publication No. CN216429562U discloses an adaptive gas lift valve. In this valve, injection pressure acts on a dual-valve-stem mechanism from the inlet. When the upward thrust of the injection pressure on the dual-valve-stem mechanism is less than the downward pressure of nitrogen on it, the mechanism is pressed against the top of the valve seat, preventing the inlet from connecting to the airflow channel, thus closing the gas lift valve. When the injection pressure exceeds the downward pressure of nitrogen, the mechanism slides upward, opening the airflow channel and allowing the injected high-pressure gas to enter the oil pipe through the inlet, airflow channel, and outlet, thus opening the gas lift valve. As the injection pressure continues to increase, the dual-valve-stem mechanism continues to move upward. When it rises to press against the bottom of the valve seat, it closes the airflow channel, and the gas lift valve automatically closes.

[0008] This existing technology allows the injection pressure to fluctuate within a certain range, and it cannot change the opening pressure.

[0009] In summary, the technical solutions, technical problems to be solved, and beneficial effects of the above-disclosed technologies are all different from those of this utility model. For more technical features, technical problems to be solved, and beneficial effects of this utility model, the above-disclosed technical documents do not provide any technical inspiration. Summary of the Invention

[0010] In view of the above-mentioned defects in the existing technology, the purpose of this utility model is to provide a mechanical air lift valve.

[0011] To achieve the above objectives, the present invention adopts the following technical solution:

[0012] A mechanical air lift valve includes an air lift valve body, a valve seat disposed within the air lift valve body, a valve stem disposed above the valve seat within the air lift valve body, a force transmission ring disposed on the valve stem, the force transmission ring being sealed to the air lift valve body, an air injection hole disposed between the valve seat and the force transmission ring in the air lift valve body, a valve stem reset mechanism connected to the upper end of the air lift valve body; a pressure loading mechanism connected to the upper end of the reset mechanism; the valve stem passing through the valve stem reset mechanism and inserted into the pressure loading mechanism; under the action of the reset mechanism, the valve stem seals the valve seat.

[0013] Furthermore, the valve stem includes a force transmission shaft, the outer diameter of which increases sequentially from top to bottom;

[0014] Specifically, the force transmission shaft consists of a positioning shaft, a sliding shaft, a limiting shaft, and a force transmission ring from top to bottom. The lower end of the force transmission ring is connected to a pneumatic valve core. There is an air passage between the pneumatic valve core and the air-lift valve body. The pneumatic valve core can seal the valve seat.

[0015] Furthermore, the pressure loading mechanism includes a pressure regulating sleeve, a pressure regulator, and a first elastic element;

[0016] Specifically, the lower end of the pressure regulating sleeve is connected to the upper end of the reset mechanism;

[0017] Specifically, the pressure regulator includes, from top to bottom, a tool handle, an adjusting shaft, and a positioning rod;

[0018] Specifically, the adjusting shaft is threadedly connected to the inner wall of the pressure regulating sleeve, and the adjusting shaft is sealed to the inner wall of the pressure regulating sleeve;

[0019] Specifically, a limiting step is used for transition between the adjusting shaft and the tool handle, and a limiting ring is provided on the inner wall of the upper end of the pressure adjusting sleeve, which can contact the limiting step;

[0020] Specifically, the upper end face of the sliding shaft extends into the pressure adjusting sleeve, the positioning shaft is fitted with a support ring, and the support ring contacts the upper end face of the sliding shaft;

[0021] Specifically, the upper end of the first elastic element is sleeved on the outer wall of the positioning rod, the lower end of the first elastic element is sleeved on the outer wall of the positioning shaft, and the lower end of the first elastic element is in contact with the support ring.

[0022] Preferably, the first elastic element is a spring.

[0023] Furthermore, a sealing cap is connected to the upper end of the pressure regulating sleeve.

[0024] Furthermore, an upper resistance reducer is provided between the first elastic element and the adjusting shaft of the pressure regulator, and the support ring is a lower resistance reducer. Both the upper and lower resistance reducers are made of rubber material.

[0025] Furthermore, the reset mechanism includes a reset sleeve and a second elastic element;

[0026] Specifically, the outer wall of the reset sleeve is connected to the inner wall of the upper end of the air lift valve body, the inner wall of the reset sleeve is slidably fitted with the sliding shaft, and the outer wall of the upper end of the reset sleeve is connected to the pressure regulating sleeve.

[0027] Specifically, the second elastic element is sleeved on the outer wall of the limiting shaft, the upper end of the second elastic element is engaged with the lower end of the reset sleeve, the lower end of the second elastic element is in contact with the upper end face of the force transmission ring, and the second elastic element is always in a compressed state.

[0028] Preferably, the second elastic element is a bellows.

[0029] Furthermore, the pneumatic valve core includes a valve core stud, a valve core body, and a valve core hemisphere connected in sequence, and the valve core stud is threadedly connected to the force transmission ring of the force transmission shaft.

[0030] Furthermore, the valve seat is assembled in the valve seat body, the upper outer wall of the valve seat body is connected to the inner wall of the air lift valve body, and a one-way valve is connected to the lower end of the valve seat body.

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] When using this invention, on-site staff can set the opening pressure according to the design requirements without the need for special equipment or professional personnel. It is convenient, quick, and reusable, greatly improving on-site construction efficiency and reducing crude oil development costs. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of a mechanical air lift valve according to this utility model;

[0034] Figure 2 This is a schematic diagram of the pneumatic valve core in this utility model;

[0035] Figure 3 This is a schematic diagram of the force transmission shaft in this utility model.

[0036] In the diagram: 1. Upper sealing cap; 2. Pressure regulating sleeve; 3. Pressure regulator; 3-1. Limiting step; 4-1. Upper drag reducer; 4-2. Lower drag reducer; 5. First elastic element; 6. Second elastic element; 7. Air lift valve body; 7-1. Air injection port; 8. Pneumatic valve core; 8-1. Valve core stud; 8-2. Valve core body; 8-3. Valve core hemisphere; 9. Valve seat; 10. Valve seat body; 11. Check valve; 12. Force transmission shaft; 12-1. Positioning shaft; 12-2. Sliding shaft; 12-3. Limiting shaft; 12-4. Force transmission ring; 12-5. Connecting shaft; 13. Reset sleeve. Detailed Implementation

[0037] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example 1

[0038] Please see Figures 1 to 3This utility model provides a mechanical air lift valve, including an air lift valve body 7, a valve seat 9 disposed inside the air lift valve body 7, a valve stem disposed inside the air lift valve body 7, the valve stem being located above the valve seat, the valve stem being provided with a force transmission ring 12-4, the force transmission ring 12-4 being sealed to the air lift valve body 7, the air lift valve body 7 having an air injection hole 7-1 between the valve seat 9 and the force transmission ring 12-4, the upper end of the air lift valve body 7 being connected to a valve stem reset mechanism, the upper end of the reset mechanism being connected to a pressure loading mechanism, the valve stem passing through the valve stem reset mechanism and inserting into the pressure loading mechanism, the valve stem sealing the valve seat under the action of the reset mechanism, and the lower end of the air lift valve body 7 being connected to a one-way valve 11.

[0039] Preferably, four air injection holes 7-1 are provided and are evenly distributed along the circumference of the air injection valve body 7.

[0040] The valve stem includes a force transmission shaft 12, the outer diameter of which increases sequentially from top to bottom. The limiting shaft 12-3 consists of a positioning shaft 12-1, a sliding shaft 12-2, a limiting shaft 12-3, and a force transmission ring 12-4, which are connected to the lower end of the force transmission ring 12-4. There is an air passage between the pneumatic valve core 8 and the air lift valve body 7. The pneumatic valve core 8 can block the valve seat 9.

[0041] The reset mechanism includes a reset sleeve 13 and a second elastic element 6. The outer wall of the reset sleeve 13 is connected to the inner wall of the upper end of the air lift valve body 7. The inner wall of the reset sleeve 13 is slidably engaged with the sliding shaft 12-2. The second elastic element 6 is sleeved on the outer wall of the limiting shaft 12-3. The upper end of the second elastic element 6 is engaged with the lower end of the reset sleeve 13. The lower end of the second elastic element 6 is in contact with the upper end face of the force transmission ring 12-4. When the force transmission shaft 12 moves upward, the upper end face of the limiting shaft 12-3 is in contact with the lower end of the reset sleeve 13, thus restricting the upward movement of the force transmission shaft 12.

[0042] The second elastic element 6 is always in a compressed state, so that the force transmission shaft 12 can be reset to its original position. The initial elastic force of the second elastic element 6 is the minimum opening pressure of a mechanical air lift valve.

[0043] Specifically, a convex ring is provided on the inner wall of the lower end of the reset sleeve 13, and the second elastic element 6 is sleeved on the outer wall of the convex ring. The deformation at the end of the second elastic element 6 is large. By using the convex ring to contact the limiting shaft 12-3, the end of the second elastic element 6 can be avoided from being damaged by the limiting shaft 12-3.

[0044] Preferably, the second elastic element 6 is a bellows.

[0045] The pressure loading mechanism includes a pressure regulating sleeve 2, a pressure regulator 3, and a first elastic element 5. The lower inner wall of the pressure regulating sleeve 2 is threadedly connected to the upper outer wall of the reset sleeve 13. The lower end face of the pressure regulating sleeve 2 contacts the upper end face of the valve body. The pressure regulator 3 includes a tool handle, an adjusting shaft, and a positioning rod from top to bottom. A limiting step 3-1 is used for transition between the adjusting shaft and the tool handle. The adjusting shaft is threadedly connected to the inner wall of the pressure regulating sleeve 2, and the adjusting shaft is sealed to the inner wall of the pressure regulating sleeve 2. The upper inner wall of the pressure regulating sleeve 2 is provided with... A limiting ring is placed, which can contact the limiting step 3-1 to prevent the pressure regulator 3 from dislodging. The upper end face of the sliding shaft 12-2 extends into the pressure regulating sleeve 2. The positioning shaft 12-1 is fitted with a support ring, which contacts the upper end face of the sliding shaft 12-2. The upper end of the first elastic element 5 is fitted on the outer wall of the positioning rod, and the lower end of the first elastic element 5 is fitted on the outer wall of the positioning shaft 12-1. The lower end of the first elastic element 5 contacts the support ring. By rotating the pressure regulator 3, the first elastic element 5 is compressed, and the force on the force transmission shaft 12 is adjusted.

[0046] Preferably, the first elastic element 5 is a spring.

[0047] Specifically, a sealing cap 1 is threaded onto the outer wall of the upper end of the pressure regulating sleeve 2 to protect the tool handle of the pressure regulator 3.

[0048] Specifically, the tool handle is cylindrical, and an internal hexagonal pressure adjustment hole is provided at the upper end of the tool handle.

[0049] Preferably, the force transmission ring 12-4 is sealed to the air lift valve body 7, the adjusting shaft and the pressure adjusting sleeve 2 by a sealing ring.

[0050] Preferably, the reset sleeve 13 is sealed to the air lift valve body 7, the pressure regulating sleeve 2 is sealed to the reset sleeve 13, and the pressure regulating sleeve 2 is sealed to the upper sealing cap 1 by threaded engagement or by sealing ring.

[0051] The one-way valve 11 is a prior art technology, including a one-way valve body, a one-way valve core 11-1, and a return spring. A spring seat is provided in the one-way valve body, and the center of the spring seat is an air passage hole. The one-way valve 11 prevents the liquid column in the oil pipe from entering a mechanical air lift valve. Example 2

[0052] Based on Example 1, this example provides a method for using a mechanical air lift valve, including the following steps:

[0053] The elastic force of different advance amounts is obtained by the elastic coefficient of the first elastic element 5. The position of the pressure regulator 3 is adjusted to set the opening pressure of a mechanical gas lift valve. The lower end of the gas lift valve body 7 of the mechanical gas lift valve is connected to the gas injection port of the tubing. The gas lift tubing is lowered into the well and nitrogen is injected from the annulus.

[0054] Nitrogen enters the injection port 7-1, and the gas pressure acts on the force transmission ring 12-4. The liquid column pressure in the oil pipe acts on the one-way valve core 11-1. When the nitrogen pressure is greater than the sum of the elastic forces of the second elastic element 6 and the first elastic element 5, the pneumatic valve core 8 moves upward, and the nitrogen pushes open the one-way valve core 11-1 and enters the oil pipe, pushing out the liquid in the oil pipe.

[0055] It should be noted that the gas lift tubing itself is prior art, such as the disclosure in CN110761743A, which discloses a heavy oil dilution gas lift process tubing and implementation method, which is clear to those skilled in the art. Example 3

[0056] Based on Embodiment 1, this embodiment further improves the service life of a mechanical air lift valve. An upper resistance reducer 4-1 is provided between the first elastic element 5 and the adjusting shaft of the pressure regulator 3, and the support ring is a lower resistance reducer 4-2. The upper resistance reducer 4-1 and the lower resistance reducer 4-2 have low rotational resistance and are used to enable the upper and lower ends of the first elastic element 5 to rotate synchronously. In particular, when the first elastic element 5 is a spring, the upper resistance reducer 4-1 and the lower resistance reducer 4-2 can prevent the spring from twisting when adjusting the opening pressure.

[0057] Please see Figure 2 The pneumatic valve core 8 includes a valve core stud 8-1, a valve core body 8-2, and a valve core hemisphere 8-3 connected in sequence. The valve core stud 8-1 is threadedly connected to the force transmission shaft. When the valve core hemisphere 8-3 is damaged, the pneumatic valve core 8 can be directly replaced.

[0058] Specifically, the lower end of the force transmission ring 12-4 is provided with a connecting shaft 12-5, and the connecting shaft 12-5 is provided with a countersunk hole, which is threadedly connected to the valve core stud 8-1.

[0059] The valve seat 9 is assembled in the valve seat body 10. The upper outer wall of the valve seat body 10 is threadedly connected to the inner wall of the air lift valve body 7. The valve seat 9 and the valve seat body 10 are sealed with a sealing ring. The lower end of the valve seat body 10 is connected to the one-way valve 11. The outer wall of the valve seat body 10 is provided with a ridge for easy mounting.

[0060] All components not discussed in detail in this application, as well as the connection methods of these components, are well-known technologies in this field. They can be directly applied and will not be elaborated further.

[0061] In this utility model, the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0062] In the description of this utility model, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0063] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0064] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A mechanical air lift valve, comprising an air lift valve body, a valve seat disposed within the air lift valve body, a valve stem disposed above the valve seat within the air lift valve body, a force transmission ring disposed on the valve stem, the force transmission ring being sealed to the air lift valve body, an air injection hole disposed between the valve seat and the force transmission ring in the air lift valve body, and a valve stem reset mechanism connected to the upper end of the air lift valve body. Its features are, The upper end of the reset mechanism is connected to a pressure loading mechanism; The valve stem passes through the valve stem reset mechanism and is inserted into the pressure loading mechanism; The valve stem blocks the valve seat under the action of the reset mechanism.

2. The mechanical air lift valve according to claim 1, characterized in that, The valve stem includes a force transmission shaft, and the outer diameter of the force transmission shaft increases sequentially from top to bottom; The force transmission shaft consists of a positioning shaft, a sliding shaft, a limiting shaft, and a force transmission ring from top to bottom. The lower end of the force transmission ring is connected to a pneumatic valve core. There is an air passage between the pneumatic valve core and the air lift valve body. The pneumatic valve core can seal the valve seat.

3. A mechanical air lift valve according to claim 2, characterized in that, The pressure loading mechanism includes a pressure regulating sleeve, a pressure regulator, and a first elastic element; The lower end of the pressure regulating sleeve is connected to the upper end of the reset mechanism; The pressure regulator includes, from top to bottom, a tool handle, an adjusting shaft, and a positioning rod; The adjusting shaft is threadedly connected to the inner wall of the pressure regulating sleeve, and the adjusting shaft is sealed to the inner wall of the pressure regulating sleeve; A limiting step is used for transition between the adjusting shaft and the tool handle, and a limiting ring is provided on the inner wall of the upper end of the pressure adjusting sleeve, which can contact the limiting step; The upper end face of the sliding shaft extends into the pressure adjusting sleeve, and the positioning shaft is fitted with a support ring, which contacts the upper end face of the sliding shaft. The upper end of the first elastic element is fitted onto the outer wall of the positioning rod, the lower end of the first elastic element is fitted onto the outer wall of the positioning shaft, and the lower end of the first elastic element is in contact with the support ring.

4. A mechanical air lift valve according to claim 3, characterized in that, The first elastic element is a spring.

5. A mechanical air lift valve according to claim 3, characterized in that, The upper end of the pressure regulating sleeve is connected to a sealing cap.

6. A mechanical air lift valve according to claim 3, characterized in that, An upper resistance reducer is provided between the first elastic element and the adjusting shaft of the pressure regulator, and the support ring is a lower resistance reducer. Both the upper and lower resistance reducers are made of rubber.

7. A mechanical air lift valve according to claim 3, characterized in that, The reset mechanism includes a reset sleeve and a second elastic element; The outer wall of the reset sleeve is connected to the inner wall of the upper end of the air lift valve body, the inner wall of the reset sleeve is slidably fitted with the sliding shaft, and the outer wall of the upper end of the reset sleeve is connected to the pressure regulating sleeve. The second elastic element is sleeved on the outer wall of the limiting shaft. The upper end of the second elastic element is engaged with the lower end of the reset sleeve, and the lower end of the second elastic element is in contact with the upper end face of the force transmission ring. The second elastic element is always in a compressed state.

8. A mechanical air lift valve according to claim 7, characterized in that, The second elastic element is a bellows.

9. A mechanical air lift valve according to any one of claims 2-8, characterized in that, The pneumatic valve core includes a valve core stud, a valve core body, and a valve core hemisphere connected in sequence. The valve core stud is threadedly connected to the force transmission ring of the force transmission shaft.

10. A mechanical air lift valve according to any one of claims 1-8, characterized in that, The valve seat is assembled in the valve seat body, the upper outer wall of the valve seat body is connected to the inner wall of the air lift valve body, and a one-way valve is connected to the lower end of the valve seat body.

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