Negative pressure yield increasing integrated device for low-efficiency well

Abstract

The invention relates to the technical field of oil exploitation, in particular to a low-efficiency well negative pressure yield increasing integrated device which comprises a Christmas tree and an oil extraction machine, the Christmas tree is connected with a first-stage negative pressure yield increasing assembly, and the first-stage negative pressure yield increasing assembly comprises a piston structure, a pressure stabilizing structure and a negative pressure structure; the input end of the piston structure is movably connected with a walking beam of the oil extractor, the pressure stabilizing structure is communicated with the output end of the piston structure and the negative pressure structure through a one-way valve, the negative pressure structure comprises a negative pressure pipe and a pressure return pipe, the negative pressure pipe is communicated with a wellhead through the one-way valve, and the pressure return pipe is communicated with the negative pressure structure through the one-way valve. Pressure fluctuation of compression and release actions of the piston is buffered through the pressure stabilizing structure, and meanwhile, the negative pressure structure forms a dynamic upward pressurizing environment at a wellhead based on pressure difference generated by piston movement; the wellhead pressure is regulated and controlled in real time, the negative pressure environment is actively generated, the resistance of wellbore accumulated liquid to gas-liquid flowing is reduced, and therefore oil gas is promoted to continuously flow from a stratum to a wellhead.

Description

Technical Field

[0001] The present invention relates to the technical field of oil extraction, and specifically refers to an integrated device for increasing production under negative pressure in low-efficiency wells. Background Art

[0002] During the exploitation of natural gas wells, as the exploitation progresses, liquids such as free water, hydrocarbon condensate liquid, and condensate water in the formation will enter the wellbore to form wellbore liquid accumulation or gas well liquid accumulation, resulting in a sharp drop in the pressure difference between the wellhead and the bottom hole, preventing the produced gas from flowing to the wellhead and rapidly reducing the gas well output. As the liquid accumulation increases, the gas production gradually decreases until there is no production. In order to increase the gas production of gas wells, it is usually necessary to carry out an enhanced production process for low-efficiency wells.

[0003] The enhanced production process for oil and gas wells is a technical process to improve the production capacity of oil and gas wells. Usually, fracturing technology, perforation technology, or multi-branch drilling technology is used. When the packer in the prior art is used for the enhanced production process, it cannot adapt to the pressure changes in the oil well, and thus cannot output crude oil under variable pressure. In addition, after the above enhanced production process treatment, the production capacity of low-efficiency wells is still limited by the pressure at the wellhead of the Christmas tree. Therefore, there is an urgent need for an integrated device for increasing production under negative pressure in low-efficiency wells. Summary of the Invention

[0004] The main purpose of the present invention is to provide an integrated device for increasing production under negative pressure in low-efficiency wells, aiming to solve the problem that low-efficiency wells in the prior art cannot utilize the pressure change in the oil well to increase the enhanced production process.

[0005] To achieve the above purpose, the present invention provides an integrated device for increasing production under negative pressure in low-efficiency wells, including a Christmas tree and a pumping unit arranged at the wellhead of the low-efficiency well. The Christmas tree is connected with a primary negative pressure enhanced production component, and the primary negative pressure enhanced production component includes a piston structure, a pressure stabilizing structure, and a negative pressure structure.

[0006] The input end of the piston structure is movably connected with the walking beam of the pumping unit. The pressure stabilizing structure is respectively communicated with the output end of the piston structure and the negative pressure structure through one-way valves. The negative pressure structure includes a negative pressure pipe and a back pressure pipe. The negative pressure pipe is communicated with the wellhead through a one-way valve, and the back pressure pipe is communicated with the negative pressure structure through a one-way valve.

[0007] During the operation of the pumping unit, the reciprocating motion of the piston structure can be realized through the swinging of the walking beam, and then the pressure increase of the negative pressure structure on the wellhead can be realized through the reciprocating motion of the piston structure.

[0008] Optionally, the negative pressure structure further includes a negative pressure cylinder. A plug rod is slidably arranged in the negative pressure cylinder. An elastic member is arranged on one side of the negative pressure cylinder close to the wellhead. The negative pressure pipe is communicated with one side of the negative pressure cylinder close to the wellhead, and the back pressure pipe is communicated with the side of the negative pressure cylinder far from the wellhead. The plug rod includes a plug head, and the pressure stabilizing structure is communicated with one side of the negative pressure cylinder close to the plug head.

[0009] Optionally, the voltage stabilizing structure includes a voltage stabilizing tank, a voltage stabilizing component is arranged in the voltage stabilizing tank, and two ends of the voltage stabilizing tank are respectively communicated with the negative pressure cylinder and the piston structure.

[0010] Optionally, the voltage stabilizing structure is connected with a secondary negative pressure production increasing component, the secondary negative pressure production increasing component includes a pressurizing tank, the pressurizing tank is communicated with one side of the negative pressure cylinder away from the plug through a one-way valve, and nitrogen is introduced into the pressurizing tank.

[0011] Optionally, the secondary negative pressure production increasing component further includes a pressurizing component, and two ends of the pressurizing component are respectively communicated with the pressurizing tank and the voltage stabilizing structure through one-way valves.

[0012] Optionally, the pressurizing component includes a hollow pressurizing seat, the pressurizing seat respectively includes a negative pressure area and a pressurizing area, a rotating shaft is rotatably arranged in the pressurizing seat, a pressurizing turbine and a negative pressure turbine are respectively arranged on two sides of the rotating shaft, the pressurizing turbine is arranged in the pressurizing area, the negative pressure turbine is arranged in the negative pressure area, an air outlet of the pressurizing area is communicated with the pressurizing tank, and an air inlet of the negative pressure area is communicated with the voltage stabilizing structure.

[0013] Optionally, a plurality of flow channels are arranged inside the voltage stabilizing component.

[0014] Optionally, the integrated device further includes a packer, the packer includes a pressure-sensitive bellows and a hydraulic component, and the hydraulic component is arranged inside the packer and is used for controlling the pressure change of different packing sections of the packer.

[0015] Optionally, nitrogen is introduced into the air inlet end of the piston structure, the air inlet end of the pressurizing component, and the air inlet of the pressurizing area.

[0016] Optionally, the negative pressure pipe and the plurality of flow channels inside the voltage stabilizing component are all Venturi tubes with spiral flow channels, and the throat diameter ratio is 1:8.

[0017] An integrated device for enhancing production under negative pressure in inefficient wells proposed in an embodiment of the present invention systematically solves the technical problem in existing inefficient well production enhancement processes that it is impossible to effectively utilize the pressure change of the oil well itself to achieve continuous production enhancement by innovatively combining mechanical linkage, pressure dynamic regulation, and negative pressure generation technologies, and significantly improves the adaptability and energy efficiency of the device. Specifically, during operation, the periodic swing of the oil pumping unit is converted into the mechanical reciprocating motion of the piston structure. The compression and release actions of the piston buffer the pressure fluctuation through the pressure stabilizing structure. At the same time, based on the pressure difference generated by the piston movement, the negative pressure structure forms a dynamic upward pressurized environment at the wellhead. The negative pressure pipe introduces the wellhead liquid accumulation or gas into the negative pressure structure through a check valve, and the back pressure pipe maintains the stability of the system through reverse pressure balance. This linkage mechanism realizes the real-time regulation of the wellhead pressure. By actively generating a negative pressure environment, it reduces the resistance of the wellbore liquid accumulation to the gas-liquid flow, thereby promoting the continuous flow of oil and gas from the formation to the wellhead. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic structural diagram of the present invention;

[0019] Figure 2 is a schematic structural diagram of the primary negative pressure production enhancement component and the secondary negative pressure production enhancement component of the present invention;

[0020] Figure 3 is a schematic internal structural diagram of the negative pressure cylinder of the present invention;

[0021] Figure 4 is a schematic structural diagram of the pressure boosting component of the present invention;

[0022] Figure 5 is a schematic internal structural diagram of the pressure boosting component of the present invention;

[0023] Figure 6 is a schematic structural diagram of the packer of the present invention.

[0024] REFERENCE SIGNS:

[0025] 1 - oil pumping unit, 2 - Christmas tree, 3 - wellhead, 4 - primary negative pressure production enhancement component, 6 - secondary negative pressure production enhancement component, 7 - packer;

[0026] 11 - walking beam;

[0027] 41 - piston structure, 42 - pressure stabilizing structure, 43 - negative pressure structure;

[0028] 421 - pressure stabilizing tank;

[0029] 431 - negative pressure pipe, 432 - back pressure pipe, 433 - negative pressure cylinder, 434 - plug rod, 435 - elastic member, 436 - plug head;

[0030] 61 - pressure boosting component, 62 - pressure boosting tank;

[0031] 611 - Boosting seat, 612 - Negative pressure area, 613 - Boosting area, 614 - Rotating shaft, 615 - Boosting turbine;

[0032] 71 - Pressure - sensitive bellows, 72 - Hydraulic component.

[0033] The realization of the object of the present invention, functional features and advantages will be further described in conjunction with embodiments with reference to the accompanying drawings. Detailed implementation manners

[0034] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0035] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0036] In the present invention, unless otherwise clearly defined and limited, terms such as "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal connection of two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0037] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and / or" appearing throughout the text includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution that satisfies both A and B at the same time. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0038] Embodiment:

[0039] Please refer to the attached Figures 1 to 6 In this embodiment, an integrated device for increasing production under negative pressure in low - efficiency wells is provided, which includes a Christmas tree 2 and a pumping unit 1 arranged at the wellhead 3 of the low - efficiency well. The Christmas tree 2 is connected with a primary negative - pressure production - increasing component 4. The primary negative - pressure production - increasing component 4 includes a piston structure 41, a pressure - stabilizing structure 42, and a negative - pressure structure 43;

[0040] The input end of the piston structure 41 is movably connected with the walking beam 11 of the pumping unit 1. The pressure - stabilizing structure 42 is communicated with the output end of the piston structure 41 and the negative - pressure structure 43 respectively through one - way valves. The negative - pressure structure 43 includes a negative - pressure pipe 431 and a back - pressure pipe 432. The negative - pressure pipe 431 is communicated with the wellhead 3 through a one - way valve, and the back - pressure pipe 432 is communicated with the negative - pressure structure 43 through a one - way valve;

[0041] During the operation of the pumping unit 1, the reciprocating motion of the piston structure 41 can be realized through the swing of the walking beam 11, and then the pressure increase of the negative - pressure structure 43 on the wellhead 3 can be realized through the reciprocating motion of the piston structure 41.

[0042] It can be understood that in the prior art, the production - increasing processes for low - efficiency wells (such as fracturing and perforating) mainly rely on external energy input (such as high - pressure pumping), which not only has high costs but also is difficult to adapt to the complex and changeable pressure environment in the well. Especially when the accumulated liquid in the wellbore causes a sudden drop in the pressure difference between the wellhead 3 and the bottom hole, the traditional processes cannot effectively utilize the pressure fluctuations in the well to restore production capacity. In addition, existing devices such as packers 7 are prone to seal failure or response lag in scenarios of dynamic pressure changes, further limiting the production - increasing effect.

[0043] Based on the above problems, an integrated device for increasing production under negative pressure in low - efficiency wells is proposed in this embodiment. By innovatively combining mechanical linkage, dynamic pressure regulation, and negative - pressure generation technologies, the technical problem that the existing production - increasing processes for low - efficiency wells cannot effectively utilize the pressure changes of the oil well itself to achieve continuous production increase is systematically solved, and the adaptability and energy efficiency of the device are significantly improved. Specifically, during operation, the periodic swing of the pumping unit 1 is converted into the mechanical reciprocating motion of the piston structure 41. The compression and release actions of the piston buffer the pressure fluctuations through the pressure - stabilizing structure 42. At the same time, the negative - pressure structure 43 forms a dynamic upward pressurized environment at the wellhead 3 based on the pressure difference generated by the piston movement. The negative - pressure pipe 431 introduces the liquid or gas accumulated at the wellhead 3 into the negative - pressure structure 43 through a one - way valve, and the back - pressure pipe 432 maintains the stability of the system through reverse pressure balance. This linkage mechanism realizes the real - time regulation of the pressure at the wellhead 3. By actively generating a negative - pressure environment, the resistance of the wellbore liquid accumulation to the gas - liquid flow is reduced, thereby promoting the continuous flow of oil and gas from the formation to the wellhead 3.

[0044] It can be understood that the walking beam 11 of the oil pumping unit 1 swings regularly during the oil production process, and its swing is transmitted to the input end of the piston structure 41 through mechanical connection, driving the piston to reciprocate in the cylinder. During the compression stroke of the piston (moving towards the wellhead 3), the gas or fluid in the cylinder is compressed, while during the return stroke (moving away from the wellhead 3), a local vacuum is formed in the cylinder, generating suction, and then converting the negative pressure in the negative pressure structure 43 into a pressurization process at the wellhead 3.

[0045] It can also be understood that the output end of the piston structure 41 is connected to the pressure stabilizing structure 42 through a one-way valve. The pressure stabilizing structure 42 is mainly composed of a pressure stabilizing tank 421 and internal pressure stabilizing components. When the piston compresses, the high-pressure gas enters the pressure stabilizing tank 421 through the one-way valve, and the pressure stabilizing components in the tank decelerate and disperse the high-speed airflow through the spiral flow channel design, avoiding the impact of pressure peaks on the downstream system; during the return stroke of the piston, the gas in the pressure stabilizing tank 421 flows back to the piston structure 41 through another one-way valve to supplement the vacuum area in the cylinder and maintain the pressure balance of the system.

[0046] Finally, during the return stroke of the piston, the negative pressure formed in the cylinder is transmitted to the wellhead 3 through the negative pressure pipe 431, and the gas in the wellbore is sucked into the negative pressure pipe 431 and enters the negative pressure cylinder 433. The piston rod 434 slidably arranged in the negative pressure cylinder 433 cooperates with the elastic member 435. When the negative pressure pipe 431 sucks the fluid at the wellhead 3, the piston rod 434 is pushed by the fluid to move away from the wellhead 3 direction, compressing the elastic member 435 in the negative pressure cylinder 433. At this time, the back pressure pipe 432 is connected to the side of the negative pressure cylinder 433 away from the wellhead 3 through a one-way valve, and releases the excess pressure to the pressure stabilizing structure 42 or the secondary pressurization component to avoid pressure accumulation in the cylinder.

[0047] Both the negative pressure pipe 431 and the back pressure pipe 432 are configured with one-way valves to ensure that the fluid only flows in the designed direction. Specifically, the negative pressure pipe 431 only opens during the return stroke of the piston, allowing the fluid at the wellhead 3 to enter the negative pressure cylinder 433; the back pressure pipe 432 opens when the piston compresses or the pressure in the negative pressure cylinder 433 is too high, guiding the pressure to the pressure stabilizing tank 421 or the external environment.

[0048] In some embodiments, high-pressure nitrogen is filled into the inlet end of the piston structure 41.

[0049] In some embodiments, the elastic member 435 is preferably a high-pressure spring.

[0050] In this embodiment, the negative pressure structure 43 further includes a negative pressure cylinder 433. A plug rod 434 is slidably disposed in the negative pressure cylinder 433. An elastic member 435 is disposed on one side of the negative pressure cylinder 433 close to the wellhead 3. The negative pressure pipe 431 communicates with one side of the negative pressure cylinder 433 close to the wellhead 3. The back pressure pipe 432 communicates with the other side of the negative pressure cylinder 433 away from the wellhead 3. The plug rod 434 includes a plug head 436. The pressure stabilizing structure 42 communicates with one side of the negative pressure cylinder 433 close to the plug head 436.

[0051] It should be noted that through the collaborative design of the negative pressure cylinder 433, the plug rod 434 and the elastic member 435, the technical problems of pressure imbalance at the wellhead 3 and blocked oil and gas flow caused by liquid accumulation in the wellbore during the stimulation of low - efficiency wells are systematically solved. Specifically, the negative pressure cylinder 433 serves as the core pressure regulating unit. One side of it close to the wellhead 3 communicates with the wellhead 3 through the negative pressure pipe 431, and the other side communicates with the pressure stabilizing structure 42 or the secondary pressurization assembly through the back pressure pipe 432. The plug rod 434 is slidably disposed in the negative pressure cylinder 433. One end of it is provided with a plug head 436, and the other end forms a dynamic connection with the inner wall of the negative pressure cylinder 433 through the elastic member 435. When the walking beam 11 of the pumping unit 1 drives the piston structure 41 to reciprocate, a negative pressure is formed in the cylinder body during the return stroke of the piston. The liquid or gas accumulated at the wellhead 3 is sucked into the negative pressure cylinder 433 through the negative pressure pipe 431. At this time, the fluid at the wellhead 3 pushes the plug rod 434 to move away from the wellhead 3, compressing the elastic member 435, so as to form a controllable negative pressure space in the negative pressure cylinder 433. Furthermore, it can avoid problems such as fracture plugging caused by long - term pressurization. It not only actively reduces the pressure at the wellhead 3, but also buffers the pressure fluctuation through the energy storage characteristics of the elastic member 435, avoiding the impact of instantaneous pressure on the system stability. At the same time, when the pressure in the negative pressure cylinder 433 is too high, the back pressure pipe 432 guides the excess pressure to the pressure stabilizing structure 42 or the outside through a one - way valve, further maintaining the pressure balance.

[0052] It should also be noted that by mechanically linking the periodic swing of the pumping unit 1 to the reciprocating motion of the plug rod 434 in the negative pressure cylinder 433, the pressure regulation is directly realized by using the power of the oil well itself without relying on external high - pressure equipment, significantly reducing the energy consumption and cost. Secondly, the introduction of the elastic member 435 realizes dynamic pressure compensation, smoothing the pressure change during the compression and release of the piston, and solving the problem that the traditional packer 7 is prone to failure in a dynamic pressure environment. In addition, the partition design of the negative pressure cylinder 433 combined with the directional control of the one - way valve ensures that the fluid only flows along the preset path, avoiding the interference of backflow and preventing the system from overloading through the pressure release mechanism of the back pressure pipe 432. This design also enables the pressure at the wellhead 3 to respond in real time to the piston motion state, forming a dynamic pressurization environment, continuously promoting the flow of oil and gas from the formation to the wellhead 3, and effectively overcoming the resistance of liquid accumulation in the wellbore to gas - liquid flow.

[0053] In this embodiment, the pressure stabilizing structure 42 includes a pressure stabilizing tank 421 , in which a pressure stabilizing member is disposed. Both ends of the pressure stabilizing tank 421 are respectively connected to the negative pressure cylinder 433 and the piston structure 41 .

[0054] In some embodiments, one end of the pressure-stabilizing tank 421 is connected to the output end of the piston structure 41, and the other end is connected to the negative pressure cylinder 433, forming a two-way channel for pressure transmission and buffering. The pressure-stabilizing component arranged inside the pressure-stabilizing tank 421 decelerates, disperses and balances the high-pressure airflow generated in the piston compression stage through a multi-channel structure, avoiding the pressure peak from directly impacting the negative pressure cylinder 433 and downstream components, thereby preventing sealing failure or equipment damage.

[0055] During the piston return stage, the stable pressure stored in the pressure stabilizing tank 421 flows back to the piston structure 41 through the one-way valve to supplement the pressure difference caused by the cylinder vacuum and maintain the dynamic balance of the system pressure. This not only achieves active buffering of pressure fluctuations, but also improves the airflow control efficiency through the optimization of the flow channel of the pressure stabilizing component, ensuring the continuity and stability of pressure transmission.

[0056] It is understandable that in traditional inefficient well production enhancement devices, when the piston reciprocates, sudden changes in pressure can easily lead to failure of the seal of the packer 7 or pressure imbalance at the wellhead 3. The introduction of the pressure-stabilizing tank 421 converts transient high pressure into controllable steady-state pressure output through physical storage and staged pressure release, which significantly reduces the system's sensitivity to dynamic pressure changes.

[0057] It can also be understood that the multi-channel design inside the pressure stabilizer accelerates the local airflow and forms a low-pressure area through the Venturi effect, further optimizing the pressure distribution and solving the problem of uneven pressure dispersion caused by the single flow channel of the traditional pressure stabilizer, thereby improving the adaptability to complex pressure environments. In addition, the linkage design of the pressure stabilizer tank 421, the piston structure 41, and the negative pressure cylinder 433 enables the system to use the mechanical energy of the piston movement to autonomously adjust the pressure, reducing the dependence on additional boosting equipment (such as an external high-pressure pump), and reducing energy consumption and operating costs.

[0058] In this embodiment, the pressure stabilizing structure 42 is connected to a secondary negative pressure production increase component 6, and the secondary negative pressure production increase component 6 includes a booster tank 62. The booster tank 62 is connected to the side of the negative pressure cylinder 433 away from the plug 436 through a one-way valve, and nitrogen is introduced into the booster tank 62.

[0059] The nitrogen gas introduced into the pressure boosting tank 62 serves as a pressure boosting medium. Its inert characteristics avoid the problems of oxidation corrosion, icing, or flow channel blockage caused by oxygen and moisture in traditional air media. At the same time, the high stability and compressibility of nitrogen gas significantly improve the accuracy and response speed of pressure regulation. Through the synergistic effect of nitrogen gas and the pressure boosting turbine 615, the system can achieve stable gas compression and storage in a high-pressure environment, and dynamically adjust the output pressure through a one-way valve to ensure the continuous stability of the negative pressure environment at the wellhead 3.

[0060] In this embodiment, the secondary negative pressure production enhancement assembly 6 further includes a pressure boosting member 61. Both ends of the pressure boosting member 61 are respectively connected to the pressure boosting tank 62 and the pressure stabilizing structure 42 through one-way valves.

[0061] In some embodiments, the pressure boosting member 61 includes a pressure boosting seat 611 with a hollow interior. The pressure boosting seat 611 respectively includes a negative pressure area 612 and a pressure boosting area 613. A rotating shaft 614 is rotatably arranged inside the pressure boosting seat 611. A pressure boosting turbine 615 and a negative pressure turbine are respectively arranged on both sides of the rotating shaft 614. The pressure boosting turbine 615 is placed in the pressure boosting area 613, and the negative pressure turbine is placed in the negative pressure area 612. The air outlet of the pressure boosting area 613 is connected to the pressure boosting tank 62, and the air inlet of the negative pressure area 612 is connected to the pressure stabilizing structure 42.

[0062] The pressure boosting member 61, as the core unit of the secondary negative pressure production enhancement assembly 6, is respectively connected to the pressure boosting tank 62 and the pressure stabilizing structure 42 through one-way valves at both ends, forming a closed-loop pressure regulation system. The internal partition design of the pressure boosting member 61 uses a hollow pressure boosting seat 611, which is divided into a negative pressure area 612 and a pressure boosting area 613, and the pressure boosting turbine 615 and the negative pressure turbine are linked through the rotating shaft 614. When the airflow from the pressure stabilizing structure 42 enters the negative pressure area 612, the negative pressure turbine is driven to rotate by the fluid kinetic energy, accelerating the gas flow rate and further reducing the local pressure, forming a more significant negative pressure gradient; at the same time, the pressure boosting turbine 615 compresses the gas through rotation in the pressure boosting area 613, and after increasing its pressure, it is transported to the pressure boosting tank 62. This process not only realizes the efficient conversion and reuse of energy, but also dynamically balances the pressure difference through the synergistic effect of the two turbines, ensuring the stable operation of the system in a complex pressure environment. The configuration of the one-way valve strictly restricts the airflow direction, avoids the interference of backflow, and maintains the unidirectionality and continuity of the pressure boosting and negative pressure processes.

[0063] It can be understood that the double-turbine collaborative working mechanism significantly improves the boosting efficiency. Through the active pressure reduction in the negative pressure area 612 and the precise pressure boosting in the boosting area 613, a dynamic and stable pressure difference environment is formed, effectively promoting the discharge of wellbore liquid accumulation and the continuous flow of oil and gas. Secondly, the optimization of the energy conversion path greatly reduces the system energy consumption. The boosting turbine 615 is self-driven by fluid kinetic energy without external power or hydraulic support, which not only reduces the operating cost but also enhances the applicability of the device in remote well sites. Thirdly, the closed-loop pressure regulation system, through the cooperation of the one-way valve and the boosting tank 62, realizes the active absorption and redistribution of pressure fluctuations, avoiding equipment wear or seal failure caused by sudden pressure changes and extending the service life of key components. Fourthly, the modular design of the boosting component 61 can be seamlessly integrated with the first-stage negative pressure component. By filling nitrogen into the boosting tank 62, the pressure control flexibility is further improved, enabling the device to adapt to complex working conditions with different well depths, liquid accumulation amounts, and formation permeabilities.

[0064] In some embodiments, a plurality of flow channels are provided inside the pressure stabilizing component.

[0065] It can be understood that the throat design of the Venturi tube causes the nitrogen gas to flow through here with a sharp increase in velocity. According to Bernoulli's principle, the increase in velocity leads to a significant decrease in local pressure, forming a low-pressure area, thus efficiently sucking in nitrogen gas during the piston compression stage. In the diverging section, the velocity slows down and the pressure gradually recovers. Combining with the guiding effect of the spiral flow channel, the nitrogen gas forms a rotational flow inside the flow channel, reducing the turbulent energy loss and achieving a smooth pressure recovery. This process balances the relationship between velocity and pressure changes through precise control of the throat diameter ratio, avoiding a sharp increase in flow resistance caused by an overly narrow throat and ensuring the continuity of pressure recovery in the diverging section, thereby maintaining a stable pressure gradient under the dynamic condition of intermittent nitrogen injection.

[0066] When the piston compresses, the nitrogen gas is rapidly pushed into the converging section of the Venturi tube. The low-pressure area formed by the sudden increase in velocity effectively adsorbs the liquid accumulation or gas in the wellbore. At the same time, the spiral flow channel enhances the gas-liquid mixing efficiency by guiding the fluid to rotate, reducing the pressure fluctuations caused by local eddies. When the piston returns, the pressure recovery mechanism in the diverging section and the inertial effect of the spiral flow channel work together to make the nitrogen gas pressure gradually rise back into the pressure stabilizing tank 421, avoiding the impact of sudden pressure changes on downstream components.

[0067] In this embodiment, the integrated device further includes a packer 7. The packer 7 includes a pressure-sensitive bellows 71 and a hydraulic component 72. The hydraulic component 72 is disposed inside the packer 7 and is used to control the pressure changes in different sealing sections of the packer 7.

[0068] Traditional packers 7 mostly use rigid sealing rings or passive elastomers, making it difficult to adapt to non-uniform downhole pressure distributions. Especially in horizontal wells or multi-layer staged production scenarios, seal failure or casing damage is likely to occur due to pressure differences. The active deformation ability of the pressure-sensitive bellows 71 combined with the precise control of the hydraulic component 72 enables independent pressure management for each sealed section, solving the limitations of traditional "one-size-fits-all" sealing. Secondly, the closed-loop control system of the hydraulic component 72 breaks through the technical bottlenecks of slow response speed and low adjustment accuracy of traditional packers 7 through real-time pressure feedback and dynamic adjustment.

[0069] Under the impact of gas-liquid two-phase flow, the system can adjust the bellows deformation in milliseconds to balance instantaneous pressure fluctuations and avoid the generation of sealing gaps. In addition, the multi-layer structure design of the pressure-sensitive bellows 71 enhances the anti-creep and anti-fatigue properties, and can still maintain a stable deformation response in a long-term high-pressure environment, significantly extending the service life of the packer 7.

[0070] In some embodiments, nitrogen is introduced into the air inlet end of the piston structure 41, the air inlet end of the booster 61, and the air inlet of the booster zone 613.

[0071] In this embodiment, the negative pressure pipe 431 and several flow channels inside the pressure stabilizing component are all Venturi tubes with spiral flow channels, and the throat diameter ratio is 1:8.

[0072] It can be understood that the spiral flow channel forces the fluid to flow axially in a rotating manner through internal spiral grooves or guide vanes. This rotational motion generates centrifugal force, causing the fluid to flow closely along the pipe wall, significantly reducing boundary layer separation and turbulence generation. At the same time, the spiral flow prolongs the path of the fluid in the flow channel, enhancing the conversion efficiency of kinetic energy and static pressure energy. For example, during the suction stage of the negative pressure pipe 431, the spiral flow channel guides the wellbore fluid accumulation to form a vortex flow, accelerating gas-liquid separation and reducing flow resistance; while during the pressure recovery stage of the pressure stabilizing component, the inertial effect of the spiral flow channel helps to smoothly release kinetic energy and avoid sudden pressure changes.

[0073] Design of the contraction section: The sharp contraction of the throat cross-sectional area (the diameter drops to 1 / 8 of the inlet) significantly increases the fluid velocity. According to Bernoulli's principle, the increase in flow velocity leads to a significant decrease in local static pressure, forming an efficient negative pressure suction environment, which is especially suitable for the rapid discharge of wellbore fluid accumulation.

[0074] Design of the expansion section: The expansion section after the throat achieves a smooth conversion of kinetic energy to static pressure energy with a gentle change in cross-sectional area (gradually restoring to the original diameter in proportion). The 1:8 throat diameter ratio controls the expansion angle to avoid flow separation and energy loss caused by too rapid expansion, ensuring the continuity of the pressure recovery process.

[0075] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present invention.

Claims

1. An integrated device for increasing production under negative pressure in low-efficiency wells, comprising a Christmas tree and an oil pumping unit arranged at the wellhead of a low-efficiency well, characterized in that, The Christmas tree is connected with a primary negative pressure production increase component, and the primary negative pressure production increase component includes a piston structure, a pressure stabilizing structure and a negative pressure structure; The input end of the piston structure is movably connected with the walking beam of the pumping unit. The pressure stabilizing structure is respectively communicated with the output end of the piston structure and the negative pressure structure through one-way valves. The negative pressure structure includes a negative pressure pipe and a back pressure pipe. The negative pressure pipe is communicated with the wellhead through a one-way valve, and the back pressure pipe is communicated with the negative pressure structure through a one-way valve; During the operation of the pumping unit, the reciprocating motion of the piston structure can be realized through the swing of the walking beam, and then the pressure increase of the negative pressure structure on the wellhead can be realized through the reciprocating motion of the piston structure.

2. The integrated device for increasing production under negative pressure in inefficient wells according to claim 1, wherein The negative pressure structure further includes a negative pressure cylinder, a plug rod is slidably arranged in the negative pressure cylinder, an elastic member is arranged on one side of the negative pressure cylinder close to the wellhead, the negative pressure pipe is communicated with one side of the negative pressure cylinder close to the wellhead, the back pressure pipe is communicated with the side of the negative pressure cylinder far from the wellhead, the plug rod includes a plug head, and the pressure stabilizing structure is communicated with one side of the negative pressure cylinder close to the plug head.

3. The integrated device for increasing production under negative pressure in inefficient wells according to claim 2, wherein The pressure stabilizing structure includes a pressure stabilizing tank, a pressure stabilizing member is arranged in the pressure stabilizing tank, and two ends of the pressure stabilizing tank are respectively communicated with the negative pressure cylinder and the piston structure.

4. The integrated device for increasing production under negative pressure in low-efficiency wells according to claim 2, wherein The pressure stabilizing structure is connected with a secondary negative pressure production increase component. The secondary negative pressure production increase component includes a pressurizing tank, and the pressurizing tank is communicated with the side of the negative pressure cylinder far from the plug head through a one-way valve, and nitrogen is introduced into the pressurizing tank.

5. The integrated device for increasing production under negative pressure in inefficient wells according to claim 4, wherein, The secondary negative pressure production increase component further includes a pressurizing member, and two ends of the pressurizing member are respectively communicated with the pressurizing tank and the pressure stabilizing structure through one-way valves.

6. The integrated device for increasing production under negative pressure in inefficient wells according to claim 5, wherein The pressurizing member includes a pressurizing seat with a hollow interior. The pressurizing seat respectively includes a negative pressure area and a pressurizing area. A rotating shaft is rotatably arranged in the pressurizing seat. A pressurizing turbine and a negative pressure turbine are respectively arranged on both sides of the rotating shaft. The pressurizing turbine is arranged in the pressurizing area, and the negative pressure turbine is arranged in the negative pressure area. The air outlet of the pressurizing area is communicated with the pressurizing tank, and the air inlet of the negative pressure area is communicated with the pressure stabilizing structure.

7. The integrated device for increasing production under negative pressure in inefficient wells according to claim 3, wherein A plurality of flow channels are arranged inside the pressure stabilizing member.

8. The integrated device for increasing production under negative pressure in inefficient wells according to claim 1, characterized in that, The integrated device further includes a packer, and the packer includes a pressure-sensitive bellows and a hydraulic component. The hydraulic component is arranged inside the packer and is used to control the pressure change of different sealing sections of the packer.

9. The integrated device for increasing production under negative pressure in inefficient wells according to claim 6, wherein Nitrogen is introduced into the air inlet end of the piston structure, the air inlet end of the pressurizing member, and the air inlet of the pressurizing area.

10. An integrated device for increasing production under negative pressure in low-efficiency wells according to claim 7, characterized in that, The negative pressure pipe and the plurality of flow channels inside the pressure stabilizing member are all Venturi tubes with spiral flow channels, and the throat diameter ratio is 1:8.

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