Bypass gas lift valve and gas production pipe column thereof

Abstract

The utility model provides a bypass gas lift valve which comprises an air inlet cylinder and an air outlet cylinder which are communicated with each other and used for forming a fluid flowing channel, and at least one airflow hole used for communicating the inside and the outside of the air inlet cylinder is formed in the side wall of the air inlet cylinder. A first limiting table is arranged below the air inlet hole along the inner wall of the air inlet cylinder, a second limiting table is arranged on the inner wall of the airflow cylinder, and the first limiting table and the second limiting table jointly form a cavity used for containing the one-way opening mechanism. The one-way opening mechanism can axially move in the cavity under the pressure of airflow from the airflow hole and is used for abutting against the first limiting table in a selectable mode, and therefore the channel can be selectively opened. In this way, different opening conditions of the gas lift valve can be met by arranging the one-way opening mechanisms of different specifications, and therefore the production requirement is met.

Description

Technical Field

[0001] The utility model belongs to the technical field of gas production operations, and in particular relates to a bypass gas lift valve and a gas production pipe string thereof. Background Art

[0002] During oil and gas extraction, Figure 1 As shown, it is often necessary to arrange a gas production string 10 in a wellbore 20 so that the oil and gas in the wellbore 20 can rise to the wellhead along the channel 105 formed by the gas production string 10. In this way, the oil and gas collection work is completed.

[0003] However, as wellbore 20 enters the middle and late stages of production, formation energy gradually decreases, and more and more liquid accumulates in wellbore 20, leading to a gradual decline in oil and gas production. Therefore, it is necessary to install a bypass gas lift valve connected to the production string 10. This bypass gas lift valve continuously feeds gas into the production string 10, pushing the oil and gas in the production string 10 upward. This ensures smooth oil and gas production.

[0004] Conventional bypass gas lift valves can only connect or disconnect the bypass gas lift valve from the gas production string 10 under specific conditions. However, the conditions for opening the bypass gas lift valve vary depending on its location in the wellbore 20. Therefore, a function that only connects or disconnects the bypass gas lift valve from the gas production string 10 under specific conditions cannot meet production needs. Utility Model Content

[0005] In order to overcome at least one or more of the above-mentioned defects in the prior art, the first aspect of the present invention provides a bypass gas lift valve, comprising an air inlet cylinder and an air outlet cylinder that are interconnected to form a fluid flow path, and at least one air flow hole is provided on the side wall of the air inlet cylinder for connecting the inside and outside of the air inlet cylinder.

[0006] Among them, a first limit platform is arranged along the inner wall of the air intake cylinder below the air intake hole, and a second limit platform is arranged on the inner wall of the air flow cylinder. The first limit platform and the second limit platform together form a cavity for accommodating a one-way opening mechanism. The one-way opening mechanism can move axially in the cavity under the air flow pressure from the air flow hole, and is used to abut against the first limit platform in a selective manner, thereby selectively opening the passage.

[0007] In one embodiment, the one-way opening mechanism includes a sealing portion that is sealed against the lower surface of the first limit platform, and a deformation portion arranged on the sealing portion, and the sealing portion can move axially in the cavity in a manner of compressing the deformation portion when subjected to airflow pressure.

[0008] In one embodiment, the blocking portion includes a blocking head for blocking the first limit platform, a hollow air inlet part connected to the blocking head and extending downward, and at least one through hole connecting the inside and outside of the air inlet part is provided on the air inlet part. The blocking portion also includes a hollow support rod connected to the air inlet part and extending downward, and the support rod is configured to compress the deformation part to move downward and allow the through hole to communicate with the channel.

[0009] In one embodiment, the deformation portion includes a coil spring, which is sleeved on the support rod, with one end of the coil spring connected to the support rod and the other end of the coil spring being arranged on the second limiting platform.

[0010] In one embodiment, the gas lift valve also includes a pressure opening mechanism arranged above the air inlet cylinder, the pressure opening mechanism includes a core shaft, the core shaft is arranged in the air inlet cylinder, and abuts against the upper surface of the first limit platform through the end portion, and is used to block the air flow hole and connect with the passage in an optional manner. The pressure opening mechanism also includes a pressurizing part arranged at the free end of the core shaft, which is used to apply a downward force to the core shaft.

[0011] In one embodiment, the pressurizing part includes a sleeve and a third limit platform arranged along the inner wall of the sleeve, the third limit platform is used to form a first cavity in the sleeve, the first cavity is configured as a sealed structure and is filled with gas inside, and the core shaft passes through the third limit platform and is arranged in the first cavity.

[0012] In one embodiment, the pressurizing portion further includes a one-way conducting portion sealedly connected to the first cavity, wherein the one-way conducting portion is configured to conduct from outside to inside and is used to selectively connect an inflation mechanism to inflate the first cavity.

[0013] In one embodiment, the core shaft includes a blocking portion for abutting against the first limit platform, a connecting portion connected to the blocking portion and extending upward, and a force-bearing portion arranged on the connecting portion and extending into the first cavity. The air intake cylinder also includes a fourth limit platform arranged above the air intake hole and along the inner wall of the air intake cylinder. The diameter of the hollow formed by the fourth limit platform is constructed to be larger than the blocking portion but smaller than the connecting portion, and is used to limit the downward movement of the core shaft. A boss is also provided on the outer wall of the connecting portion, which is used to abut against the fourth limit platform, thereby limiting the upward movement of the core shaft.

[0014] In one embodiment, the free end of the blocking portion is configured as a circular structure for sealingly blocking the upper surface of the first limiting platform.

[0015] According to a second aspect of the present invention, a gas production string is provided, comprising a velocity string and a mandrel for being lowered into a wellbore and communicating with each other in sequence, wherein the velocity string and the mandrel together constitute a fluid passage, a one-way valve for conducting from outside to inside is provided at the free end of the mandrel, and a packer is provided on the mandrel for sealingly connecting the mandrel to the wellbore.

[0016] Wherein, at least one bypass gas lift valve as described above is provided on the working cylinder for communicating with the working cylinder.

[0017] In general, compared with the prior art, the above technical solution conceived by the utility model can achieve at least the following beneficial effects:

[0018] In the present invention, an air intake cylinder and an air flow cylinder are provided that are interconnected to form a passage for fluid movement, and an air flow hole is provided on the air intake cylinder to connect the inside and outside of the air intake cylinder. At the same time, a first limit platform is provided along the inner wall of the air intake cylinder below the air intake hole, and a second limit platform is provided on the inner wall of the air flow cylinder. A one-way opening mechanism is provided between the first limit platform and the second limit platform, so that the one-way opening mechanism can move between the first limit platform and the second limit platform under the air flow pressure from the air flow hole, thereby selectively abutting against the first limit platform. In this way, the passage can be selectively opened. In this way, one-way opening mechanisms of different specifications can be provided to meet different opening conditions of the gas lift valve, thereby meeting production needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings, in which:

[0020] Figure 1 The overall structure of the gas production string and the bypass gas lift valve assembly is schematically shown;

[0021] Figure 2 The overall structure of the bypass gas lift valve according to the present invention is schematically shown;

[0022] Figure 3 The schematic diagram shows the overall structure of the bypass air lift valve according to the present invention, in which the air intake cylinder and the one-way opening mechanism are assembled.

[0023] It should be noted that the drawings are not necessarily drawn according to the actual scale.

[0024] In all the drawings, the same reference numerals represent the same technical features, specifically: 10-gas production string; 101-velocity string; 102-working cylinder; 103-first one-way valve; 104-packer; 105-passageway; 20-wellbore; 100-bypass gas lift valve; 1-inlet cylinder; 11-passageway; 12-air flow hole; 13-first limit platform; 14-fourth limit platform; 2-air flow cylinder; 21-second limit platform; 3-one-way opening mechanism; 31-blocking part; 311-blocking head; 312-inlet member; 313-pass Hole; 314-support rod; 32-deformation part; 4-pressure opening mechanism; 41-core shaft; 411-blocking part; 412-connecting part; 413-force-bearing part; 414-boss; 42-pressurizing part; 421-sleeve; 422-third limit platform; 423-first cavity; 424-second cavity; 425-upper joint; 426-one-way guide part; 5-sealing ring; 6-connecting sleeve; 61-sleeve; 62-first joint; 63-second joint; 7-bellows; 8-guide cylinder; 81-connecting cylinder; 82-guide head. DETAILED DESCRIPTION

[0025] In order to better understand the purpose, structure and function of the present invention, the bypass gas lift valve for a gas production string of the present invention is further described in detail below with reference to the accompanying drawings.

[0026] For convenience, the direction extending along the air intake cylinder is called "axial direction", "vertical direction" or similar terms, the direction perpendicular to the "axial direction" is called "lateral direction", "horizontal direction" or similar terms, the direction of movement from the air flow cylinder to the air intake cylinder is called "upward" or similar terms, and the direction of movement from the air intake cylinder to the air flow cylinder is called "downward" or similar terms.

[0027] Generally speaking, if Figure 1 As shown, the gas production string 10 includes a velocity string 101 and a mandrel 102, which are connected sequentially from top to bottom. In this manner, the velocity string 101 and the mandrel 102 can together form a channel 105 for fluid movement. In this arrangement, the velocity string 101 and the mandrel 102 can be lowered into the wellbore 20 together, causing the fluid in the wellbore 20 to move upward along the channel 105, thereby performing fluid collection. It should be noted that the velocity string 101 and the mandrel 102 are well known in the prior art, and their structure and operation will not be described in detail.

[0028] A one-way valve 103 is also provided at the free end of the mandrel 102. The one-way valve 103 is configured to conduct fluid from bottom to top. This ensures that fluid in the wellbore 20 can only flow from bottom to top along the channel 105, preventing fluid from flowing from the channel 105 into the wellbore 20 and causing fluid collection failure.

[0029] In one embodiment, Figure 1 As shown, the gas production string 10 further includes a packer 104 disposed around the mandrel 102 . The packer 104 is configured to be expandable along the circumferential direction for sealingly connecting the mandrel 102 and the wellbore 20 in a selectable manner.

[0030] Under this arrangement, when the fluid in the wellbore 20 needs to be extracted, a one-way valve 103 is set at the free end of the working barrel 102, and a packer 104 is set around the outer circumference of the working barrel 102. Then, the fluid channel 105 formed by the velocity string 101 and the working barrel 102 is lowered into the wellbore 20. When the channel 105 reaches a suitable position in the wellbore 20, the packer 104 is activated. At this time, the packer 104 will expand along the circumferential direction and abut against the wellbore 20, thereby forming a seal between the working barrel 102 and the wellbore 20. During this process, the fluid below the packer 104 will move along the one-way valve 103 into the channel 105 and continue to move upward along the channel 105. In this way, the fluid collection work is completed.

[0031] However, when the fluid in the mandrel 102 cannot continuously move upward, a bypass gas lift valve 100 is installed on the mandrel 102 and connected to the mandrel 102. Gas is then introduced into the bypass gas lift valve 100 to perform gas lift on the fluid in the mandrel 102, thereby enabling the fluid in the mandrel 102 to continuously move upward. It should be noted that any number of bypass gas lift valves 100 can be installed and arranged along the axis of the mandrel 102. This allows the fluid in the mandrel 102 to continuously move upward.

[0032] In this embodiment, if Figure 1 As shown, the bypass gas lift valve 100 is disposed on the outer wall of the mandrel 102 and is in communication with the interior of the mandrel 102. In this manner, the gas in the bypass gas lift valve 100 can move laterally into the mandrel 102 and exert pressure vertically upward on the fluid in the mandrel 102, thereby causing the fluid in the mandrel 102 to continuously rise.

[0033] In this configuration, when in use, the velocity string 101, mandrel 102, check valve 103, and packer 104 are first assembled in sequence. Simultaneously, an appropriate number of bypass gas lift valves 100 are installed on the outer wall of the mandrel 102, each of which is in communication with the interior of the mandrel 102. This completes the assembly of the gas production string 10. Next, the assembled gas production string 10 is lowered into the wellbore 20, positioning it appropriately within the wellbore 20.

[0034] Next, the packer 104 is activated, causing it to expand circumferentially until its outer periphery abuts the wellbore 20. At this point, a seal is formed between the mandrel 102 and the wellbore 20. Simultaneously, fluid within the wellbore 20 below the packer 104 can flow through the one-way valve 103 into the mandrel 102 and continue to flow upward along the channel 105 formed by the mandrel 102 and the velocity string 101.

[0035] When the fluid in the mandrel 102 cannot continue to move upward, gas is introduced into the space between the gas production string 10 and the wellbore 20 at the wellhead end. This gas gradually fills the space above the packer 104. Simultaneously, the gas can enter the mandrel 102 laterally along the bypass gas lift valve 100, exerting vertical upward pressure on the fluid in the mandrel 102, causing it to continue to rise. This completes the fluid collection process.

[0036] Figure 2 The overall structure of the bypass gas lift valve 100 according to the present invention is schematically shown. Figure 2 In the illustrated embodiment, the bypass gas lift valve 100 includes a hollow intake cylinder 1 and a hollow gas flow cylinder 2 interconnected with the intake cylinder 1. In this manner, the intake cylinder 1 and the gas flow cylinder 2 can jointly form a passage 11 for gas circulation. The intake cylinder 1 is provided with at least one gas flow hole 12 extending through the sidewall of the intake cylinder 1, which is used to connect the interior and exterior of the intake cylinder 1. In this manner, gas can flow into the intake cylinder 1 along the gas flow hole 12 and along the passage 11 formed by the intake cylinder 1 and the gas flow cylinder 2.

[0037] In one embodiment, Figure 3 As shown, a hollow first stop 13 is provided along the inner wall of the air intake cylinder 1, and is located below the airflow hole 12. Simultaneously, a hollow second stop 21 is provided along the inner wall of the airflow cylinder 2. The first stop 13 and the second stop 21 together form a cavity for accommodating the one-way opening mechanism 3.

[0038] In this embodiment, if Figure 3As shown, the one-way opening mechanism 3 includes a blocking portion 31 for blocking the channel on the lower surface of the first limit platform 13, and a deformation portion 32 arranged around the blocking portion 31, one end of the deformation portion 32 abuts against the blocking portion 31, and the other end is arranged on the second limit platform 21. The deformation portion 32 is made of any material that can undergo elastic deformation. In addition, it should be noted that the axial distance of the cavity formed by the first limit platform 13 and the second limit platform 21 is greater than the axial distance of the blocking portion 31. Specifically, the blocking portion 31 can move axially in the cavity in a manner that compresses the deformation portion 32 to produce deformation.

[0039] In this way, the blocking portion 31 can be subjected to the upward force generated by the deformable portion 32 under normal conditions, so that the blocking portion 31 can stably abut against the lower surface of the first limiting platform 13, thereby blocking the channel on the lower surface of the first limiting platform 13. When the blocking portion 31 is subjected to a downward force, it can compress the deformable portion 32 downward, causing the deformable portion 32 to elastically deform, causing the blocking portion 31 to move downward, thereby separating the blocking portion 31 from the first limiting platform 13. When the downward force applied to the blocking portion 31 is removed, the elastic portion 32 will restore its elastic deformation, causing the blocking portion 31 to move upward until it abuts against the first limiting platform 13.

[0040] In one embodiment, Figure 3 As shown, the blocking portion 31 includes a blocking head 311 configured to complement the shape of the channel on the lower surface of the first limiting platform 13, and a hollow air inlet member 312 disposed below the blocking head 311 and interconnected with the blocking head 311. The air inlet member 312 is configured to have a radial length greater than the radial length of the channel on the lower surface of the first limiting platform 13. In this way, the air inlet member 312 can abut against the first limiting platform 13, further blocking the channel on the lower surface of the first limiting platform 13. In addition, the one-way opening mechanism 3 can be limited by the first limiting platform 13, so that the one-way opening mechanism 3 cannot continue to move upward.

[0041] Among them, at least one through hole 313 is opened on the wall of the air inlet part 312, which passes through the wall of the air inlet part 312. The through hole 313 is used to connect the interior of the air inlet part 312 with the passage 11, so that the airflow in the passage 11 can enter the interior of the air inlet part 312 along the through hole 313 and move along the air inlet part 32.

[0042] The sealing portion 31 also includes a hollow support rod 314 connected to the air inlet member 312 and extending downward. This allows the interior of the air inlet member 312 and the interior of the support rod 314 to communicate with each other, allowing gas to flow. The elastic portion 32 is disposed around the outside of the support rod 314. In this embodiment, the elastic portion 32 is configured as a coil spring.

[0043] According to a preferred embodiment of the present invention, Figure 3 As shown, the lower surface of the first limiting platform 13 is formed into a hollow truncated cone. The diameter of the cone decreases from bottom to top. The blocking head 311 is configured as an arc-shaped structure capable of sealing the cone, and the outer contour of the air inlet 312 is configured as a cone. In this way, the blocking head 311 and the air inlet 312 can be used together to seal the first limiting platform 13 and prevent the one-way opening mechanism 3 from moving upward.

[0044] Under this setting, when the bypass gas lift valve 100 is needed to perform gas lift on the working cylinder 102, the bypass gas lift valve 100 is set on the side wall of the working cylinder 102, and the passage 11 formed by the air inlet cylinder 1 and the air flow cylinder 2 is connected to the interior of the working cylinder 102.

[0045] Then, gas is input toward the bypass gas lift valve 100. During this process, the gas will enter the channel 11 along the air flow hole 12. At this time, the gas can exert a downward force on the blocking part 31 and push the blocking part 31 to continue to move downward. In the process of the blocking part 31 continuing to move downward, the blocking part 31 will continue to compress the deformation part 32 to cause elastic deformation. As a result, the blocking head 311 and the first limit platform 13 are separated from each other, so that the through hole 313 and the passage 11 are connected to each other. At this time, the gas can continue to move along the passage 11 until it is transported into the working cylinder 102, thereby exerting upward pressure on the fluid in the working cylinder 102. Thus, the gas lift work is completed.

[0046] In one embodiment, Figure 2 As shown, the bypass gas lift valve 100 further includes a pressure opening mechanism 4 , which is disposed above the air inlet cylinder 1 and abuts against the upper surface of the channel formed by the first limiting platform 13 , thereby blocking the channel.

[0047] The pressure opening mechanism 4 includes a core shaft 41 disposed in the air inlet cylinder 1 for abutting against the first limit platform 13, and a pressurizing portion 42 disposed at the free end of the core shaft 41 for applying a downward force to the core shaft 41. In this arrangement, when the force applied by the pressurizing portion 42 to the core shaft 41 is increased, the core shaft 41 can be further abutted against the first limit platform 13, thereby blocking the channel formed by the first limit platform 13. The core shaft 41 is configured in any shape for easy installation. In the present utility model, the core shaft 41 is configured in a circular cylindrical structure.

[0048] In one embodiment, Figure 2 As shown, the core shaft 41 includes a blocking portion 411 for contacting the upper surface of the channel formed by the first limiting platform 13, and the free end of the blocking portion 411 can be located below the air flow hole 12. In this way, the blocking portion 411 can be used to separate the air flow hole 12 from the passage 11, thereby achieving blocking of the passage 11.

[0049] According to the utility model, if Figure 2 As shown, the core shaft 41 also includes a connecting portion 412 connected to the blocking portion 411 and extending upward. The blocking portion 411 is configured to have a diameter smaller than that of the connecting portion 412. Furthermore, a hollow fourth limiting platform 14 is provided on the inner wall of the air intake cylinder 1 above the air flow hole 12. The annulus formed by the fourth limiting platform 14 has a diameter larger than that of the blocking portion 411 but smaller than that of the connecting portion 412. In this way, the fourth limiting platform 14 can limit the connecting portion 412, thereby preventing the core shaft 411 from moving downward.

[0050] At the same time, the core shaft 41 also includes a force-bearing portion 413 disposed at the free end of the connecting portion 412 and connected to the pressurizing portion 42. In this arrangement, the pressurizing portion 42 can exert a downward force on the force-bearing portion 413 and transmit this force to the connecting portion 412. At this time, the pressure can be transmitted along the connecting portion 412 to the blocking portion 411. As a result, the blocking portion 411 is stably abutted against the upper surface of the first limiting platform 13.

[0051] According to a preferred embodiment of the present invention, Figure 2 As shown, a first groove (not shown) is provided on the connecting portion 412 around the connecting portion 412, and a sealing ring 5 is provided in the first groove. The sealing ring 5 is used to form a mutually sealed structure between the connecting portion 412 and the air intake cylinder 1. In this way, gas leakage can be prevented.

[0052] According to a preferred embodiment of the present invention, Figure 2As shown, the free end of the blocking portion 411 is configured as a circular structure having a diameter comparable to the diameter of the passage formed by the upper surface of the first limiting platform 13. In this manner, when airflow enters the air intake cylinder 1 from the airflow hole 12 and contacts the blocking portion 411, an upward force (F1) is applied to the blocking portion 411, thereby driving the core shaft 41 to move upward.

[0053] Under this setting, when the airflow enters the air inlet cylinder 1 along the airflow hole 12, the gas will push the blocking part 411 to move upward. At the same time, the blocking part 411 is also affected by the gravity (F2) of the core shaft 41 itself and the downward force (F3) applied by the pressurizing part 42 to the core shaft 41. When the force (F1) of the gas is greater than the gravity (F2) of the core shaft 41 plus the downward force (F3) applied by the pressurizing part 42 to the core shaft 41, the core shaft 41 will move upward. Specifically, F1>F2+F3. At this time, the blocking part 411 will be separated from the upper surface of the first limit platform 13. As a result, the airflow hole 12 connects the inside and outside of the air inlet cylinder 1, so that the gas can continue to move along the passage 11 until it is transported into the working cylinder 102, thereby applying upward pressure to the fluid in the working cylinder 102. In this way, the gas lift work is completed.

[0054] In one embodiment, Figure 2 As shown, the pressurizing portion 42 includes a hollow sleeve 421 and a hollow third limiting platform 422 provided along the inner wall of the sleeve 421. In this way, the third limiting platform 422 can separate the inner space of the sleeve 421 into a first cavity 423 for applying a force to the core shaft 41 and a second cavity 424 for accommodating the core shaft 41.

[0055] In one embodiment, Figure 2 As shown, the first cavity 423 is configured as a sealed structure, and the first cavity 423 is filled with gas. The force-bearing portion 413 is arranged in the first cavity 423 through the third limit platform 422. In this way, the force-bearing portion 413 can be subjected to the downward force applied by the gas in the first cavity 423. In the present utility model, a boss 414 is further provided around the connecting portion 412 below the force-bearing portion 413, and the boss 414 is configured to abut against the third limit platform 422. In this way, the core shaft 41 can be prevented from continuously moving upward.

[0056] According to a preferred embodiment of the present invention, Figure 2As shown, a second groove (not shown) is formed along the circumference of the inner wall of the third limiting platform 422. A sealing ring 5 is disposed in the second groove. The sealing ring 5 is used to form a mutually sealed structure between the force-bearing portion 413 and the third limiting platform 422. In this way, leakage of gas in the first cavity 423 can be prevented.

[0057] In one embodiment, Figure 2 As shown, an upper joint 425 is sealed on the first cavity 423. At the same time, a one-way conductive portion 426 for connecting to an inflation mechanism (not shown) is provided on the upper joint 425. The one-way conductive portion 426 is configured to conduct from the outside to the inside. Preferably, the one-way conductive portion 426 is configured as a one-way valve. In this way, the first cavity 423 can be quantitatively inflated according to the amount of downward force applied as needed. It should be noted that the gas is set to any inert gas.

[0058] According to the utility model, if Figure 2 As shown, the bypass gas lift valve 100 further includes a connecting sleeve 6 disposed between the air intake cylinder 1 and the sleeve 421. The ends of the connecting sleeve 6 are respectively sleeved within the air intake cylinder 1 and the sleeve 421. Threads are provided between the air intake cylinder 1, the connecting sleeve 6, and the sleeve 421. This allows the air intake cylinder 1, the connecting sleeve 6, and the sleeve 421 to be threadedly connected to form a stable, integrated structure.

[0059] Among them, such as Figure 2 As shown, the connecting sleeve 6 includes a sleeve 61, a first connector 62 provided at the upper end of the sleeve 61 and adapted to be sleeved within the sleeve 421, and a second connector 63 provided at the lower end of the sleeve 61 and adapted to be sleeved within the air intake cylinder 1. Furthermore, the sleeve 61, the air intake cylinder 1, and the sleeve 421 are configured to have equal outer diameters. In this manner, the air intake cylinder 1 and the sleeve 421 can respectively abut against the sleeve 61, thereby further ensuring a stable connection between the air intake cylinder 1, the connecting sleeve 6, and the sleeve 421.

[0060] According to a preferred embodiment of the present invention, Figure 2 As shown, a plurality of sealing rings 5 are provided around the outer wall of the second joint 63 along the circumference of the second joint 63, with the ends of the sealing rings 5 respectively abutting against the ends of the sleeve 61 and the ends of the intake cylinder 1. In this way, a sealed connection is achieved between the connecting sleeve 6 and the intake cylinder 1, thereby preventing gas leakage.

[0061] According to a preferred embodiment of the present invention, Figure 2As shown, the bypass gas lift valve 100 further includes a bellows 7 disposed around the core shaft 41. One end of the bellows 7 abuts against the first connector 62, and the other end abuts against the boss 414. The bellows 7 is made of any elastically deformable material. In this manner, the bellows 7 can buffer the forces generated by the core shaft 41 during movement.

[0062] In one embodiment, Figure 2 As shown, the bypass gas lift valve 100 also includes a guide cylinder 8 provided at the free end of the air flow cylinder 2 for communicating with the working cylinder 102. The guide cylinder 8 includes a connecting cylinder 81 sleeved in the air flow cylinder 2, and a guide head 82 interconnected with the connecting cylinder 81. A first step surface is formed between the connecting cylinder 81 and the guide head 82. At the same time, a second step surface is formed on the upper surface of the air flow cylinder 2 inwardly along the circumferential direction. In this embodiment, a plurality of sealing rings 5 are provided between the first step surface and the second step surface. In this way, the air flow cylinder 2 and the guide cylinder 8 can be connected in a sealed manner, thereby preventing gas leakage.

[0063] The bypass gas lift valve 100 according to the present invention operates as follows.

[0064] First, the velocity string 101, mandrel 102, check valve 103, and packer 104 are assembled in sequence. Simultaneously, an appropriate number of bypass gas lift valves 100 are installed on the outer wall of the mandrel 102, each of which is connected to the interior of the mandrel 102. This completes the assembly of the gas production string 10. Next, the assembled gas production string 10 is lowered into the wellbore 20, securing it in an appropriate position within the wellbore 20.

[0065] Next, the packer 104 is activated, causing it to expand circumferentially until its outer periphery abuts the wellbore 20. At this point, a seal is formed between the mandrel 102 and the wellbore 20. Simultaneously, fluid within the wellbore 20 below the packer 104 can flow through the one-way valve 103 into the mandrel 102 and continue to flow upward along the channel 105 formed by the mandrel 102 and the velocity string 101.

[0066] When the fluid in the working cylinder 102 cannot continue to move upward, it is necessary to use the bypass gas lift valve 100 to gas lift the working cylinder 102. At this time, gas is input into the space between the gas production pipe 10 and the wellbore 20 at the wellhead end, and the gas will gradually fill the space above the packer 104. At the same time, the gas can also enter the channel 11 along the air flow hole 12. At this time, the gas will contact the core shaft 41 and exert an upward force on the core shaft 41, thereby pushing the core shaft 41 to move upward. As a result, the air flow hole 12 connects the inside and outside of the air inlet cylinder 1.

[0067] As the core shaft 41 continues to move upward, the boss 414 on the core shaft abuts against the third stop 422 provided on the inner wall of the sleeve 421. At this point, the core shaft 41 is unable to move upward, preventing the gas entering the channel 11 from moving upward. Consequently, the gas can only move downward along the channel 11.

[0068] During the downward movement of the gas, the gas can exert a downward force on the blocking portion 31 and push the blocking portion 31 to continue to move downward. During the downward movement of the blocking portion 31, the blocking portion 31 will continuously compress the deformation portion 32 to cause elastic deformation. As a result, the blocking head 311 and the first limit platform 13 are separated from each other, so that the through hole 313 and the passage 11 are connected to each other. At this time, the gas can continue to move along the passage 11 until it is transported into the working cylinder 102, thereby exerting upward pressure on the fluid in the working cylinder 102. Thus, the gas lift work is completed.

[0069] When the gas input is canceled, the core shaft 41 moves downward and the blocking portion 31 moves upward, thereby blocking the channel 11 again.

[0070] It is understood that the present invention is described by way of certain embodiments, and those skilled in the art will appreciate that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. Furthermore, under the guidance of the present invention, these features and embodiments may be modified to suit specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are intended to be protected by the present invention.

Claims

1. A bypass gas lift valve, characterized in that: The invention comprises an air intake cylinder (1) and an air flow cylinder (2) which are interconnected and used to form a fluid flow passage (11); at least one air flow hole (12) is provided on the side wall of the air intake cylinder (1) for connecting the inside and outside of the air intake cylinder (1); A first limiting platform (13) is provided below the air inlet hole (12) along the inner wall of the air inlet cylinder (1), and a second limiting platform (21) is provided on the inner wall of the air flow cylinder (2). The first limiting platform (13) and the second limiting platform (21) together form a cavity for accommodating a one-way opening mechanism (3). The one-way opening mechanism (3) can move axially in the cavity under the air flow pressure from the air flow hole (12) and abut against the first limiting platform (13) in a selective manner, thereby selectively opening the passage (11).

2. The bypass gas lift valve according to claim 1, characterized in that: The one-way opening mechanism (3) comprises a blocking portion (31) for sealingly contacting the lower surface of the first limiting platform (13), and a deformation portion (32) arranged on the blocking portion (31). The blocking portion (31) can move axially in the cavity by compressing the deformation portion (32) when subjected to airflow pressure.

3. The bypass gas lift valve according to claim 2, characterized in that: The blocking portion (31) comprises a blocking head (311) for blocking the first limiting platform (13), a hollow air inlet member (312) connected to the blocking head (311) and extending downward, and at least one through hole (313) for connecting the inside and outside of the air inlet member (312) is provided on the air inlet member (312). The blocking portion (31) also comprises a hollow support rod (314) connected to the air inlet member (312) and extending downward, and the support rod (314) is configured to compress the deformation portion (32) to move downward and allow the through hole (313) to communicate with the channel (11).

4. The bypass gas lift valve according to claim 3, characterized in that: The deformation portion (32) comprises a coil spring, which is sleeved on the support rod (314), one end of which is connected to the support rod (314), and the other end of which is arranged on the second limiting platform (21).

5. The bypass gas lift valve according to any one of claims 1 to 4, characterized in that: The gas lift valve further comprises a pressure opening mechanism (4) arranged above the air inlet cylinder (1), the pressure opening mechanism (4) comprising a core shaft (41), the core shaft (41) being arranged in the air inlet cylinder (1) and being in contact with the upper surface of the first limit platform (13) through its end portion, for selectively blocking the air flow hole (12) from being connected to the passage (11), the pressure opening mechanism (4) further comprising a pressurizing portion (42) arranged at the free end of the core shaft (41) for applying a downward force to the core shaft (41).

6. The bypass gas lift valve according to claim 5, characterized in that: The pressurizing portion (42) includes a sleeve (421) and a third limiting platform (422) arranged along the inner wall of the sleeve (421). The third limiting platform (422) is used to form a first cavity (423) in the sleeve (421). The first cavity (423) is configured as a sealed structure and is filled with gas. The core shaft (41) passes through the third limiting platform (422) and is arranged in the first cavity (423).

7. The bypass gas lift valve according to claim 6, characterized in that: The pressurizing portion (42) further comprises a one-way conducting portion (426) in sealed communication with the first cavity (423), wherein the one-way conducting portion (426) is configured to conduct from outside to inside and is used to selectively connect an inflation mechanism to inflate the first cavity (423).

8. The bypass gas lift valve according to claim 7, characterized in that: The core shaft (41) includes a blocking portion (411) for abutting against the first limiting platform (13), a connecting portion (412) connected to the blocking portion (411) and extending upward, and a force-bearing portion (413) arranged on the connecting portion (412) and extending into the first cavity (423). The air intake cylinder (1) also includes a fourth limiting platform (14) arranged above the air intake hole (12) and along the inner wall of the air intake cylinder (1). The diameter of the hollow formed by the fourth limiting platform (14) is configured to be larger than the blocking portion (411) but smaller than the connecting portion (412), and is used to limit the downward movement of the core shaft (41). A boss (414) is also provided on the outer wall of the connecting portion (412) for abutting against the fourth limiting platform (14), thereby limiting the upward movement of the core shaft (41).

9. The bypass gas lift valve according to claim 8, characterized in that: The free end of the blocking portion (411) is configured as a circular structure, and is used to seal the upper surface of the first limiting platform (13).

10. A gas production string, characterized in that: The invention comprises a velocity string (101) and a working cylinder (102) for being lowered into a wellbore (20) and connected in sequence, wherein the velocity string (101) and the working cylinder (102) together form a fluid channel (105), a one-way valve (103) for conducting from outside to inside is provided at the free end of the working cylinder (102), and a packer (104) is provided on the working cylinder (102) for sealingly connecting the working cylinder (102) and the wellbore (20). Wherein, at least one bypass gas lift valve (100) according to any one of claims 1 to 9 is provided on the working cylinder (102) for communicating with the working cylinder (102).

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