Oil and gas well production section annulus self-driving fixing and sealing pipe joint, fixing and sealing method and well completion structure

Abstract

An oil and gas well production section annulus self-driving solid sealing pipe joint, a method and a well completion structure are applied to an oil and gas well of a single stratum or penetrating through multiple stratums, the self-driving solid sealing pipe joint comprises a base pipe, the whole base pipe is of a pipe cavity structure, butt joint devices are arranged at the two ends of the base pipe, and the base pipe can be connected with adjacent pipe joints in a central pipe column in an end-to-end mode; the agent storage device is arranged on the base pipe, a sealing agent is arranged in the agent storage device, the sealing agent can be injected into the shaft annulus, the sealing agent and the continuous packer jointly form a sealing body 200, and the sealing body 200 can prevent liquid in the shaft annulus from axially channeling along the shaft annulus; and the driving device 3 is arranged on the base pipe 1 and is used for driving the agent storage device 2 to inject the sealing agent 20 into the shaft annulus according to an agent injection trigger signal. According to the technical scheme provided by the embodiment of the invention, the fluid channeling prevention capacity of the continuous packer in the wellbore annulus of the oil and gas well production section can be improved, and the crude oil recovery rate is increased.

Description

Technical Field

[0001] The patent of this invention belongs to the field of oil and natural gas extraction technology, and relates to a self-driving and sealing pipe joint in the annulus of the production section of an oil and gas well, a self-driving and sealing method for the annulus of the production section of an oil and gas well, and a well completion structure. Background Art

[0002] In the field of oil and gas extraction, wellbores that penetrate multiple formations experience different oil and water fronts advancing at different speeds. The oil and water fronts of the faster-advancing formations reach the wellbore first, creating high-water-content formations. Water produced from these high-water-content formations generates axial crossflow (i.e., interlayer crossflow) within the wellbore annulus, reducing the oil production rate of other formations. Furthermore, within longer, single-formation production sections, a certain amount of axial crossflow (i.e., intralayer crossflow) also occurs within the wellbore annulus, impacting the recovery rate of the oil and gas well. To address this issue, continuous packer water control technology (see Chinese invention patents 2008100556801, 2014100135988, and 2019100846588) has emerged. The principle is to run a flow control core string (such as an ICD, AICD, or sliding sleeve) through the production section of the wellbore and fill the annulus defined by the outer wall of the core string and the inner wall of the wellbore with solid particles to form a continuous packer. This effectively limits the axial flow of water produced from high-water-content formations within the annulus. However, due to the presence of flow-through pores within the continuous packer, axial flow of produced water cannot be completely eliminated. For example, when the interlayer distance is large (for example, 30 meters), the interlayer crossflow rate of water produced from the high water-content formation is small (for example, only 20 cubic meters / day); but when the interlayer distance is small (for example, only 10 meters), the interlayer crossflow is relatively large (for example, 60 cubic meters / day), resulting in a reduction in oil production (for example, 15 cubic meters / day); for another example, when the interlayer distance is even smaller (for example, only 5 meters), the interlayer crossflow will be even greater (for example, 60 cubic meters / day), and the oil production will be further reduced (for example, 30 cubic meters / day). On this basis, the prior art has also proposed a technical solution for storage-type precise quantitative injection of glue (i.e., sealing agent) (see Chinese invention patent 2015103702195), that is, first, the corresponding capacity of sealing agent required for multiple target sealing points is stored in multiple pre-set containers, and then the multiple containers are placed in a glue injection string and lowered into the location of the target sealing point through the glue injection string once or multiple times, and the multiple containers are driven to inject glue by ground pressure. After the sealing agent solidifies, the flow-through pores inside the continuous sealing body corresponding to the target sealing point can be sealed, thereby completely solving the problem of inter-layer crossflow or intra-layer crossflow in the wellbore annulus.However, this technical solution still has the following problems: First, it is still necessary to run the injection string into the center string, which is not only complicated but also increases the operation time and cost; second, the sealing agent output by the injection string needs to pass through the center string to enter the wellbore annulus, so the corresponding injection position on the center string also needs to be preset with a check valve and other channels for outputting the sealing agent; third, before the injection string is injected into the wellbore annulus, in the string annulus defined by the outer wall of the injection string and the inner wall of the center string, it is necessary to use a packer to seal the two ends of the injection position in advance , thereby ensuring that the sealing agent can smoothly enter the wellbore annulus instead of flowing arbitrarily axially in the tubing annulus. The above problems will undoubtedly increase the complexity of the equipment and process, and also have higher construction risks and economic costs; fourthly, since the injection string needs to be lowered into the wellbore production section from the inside of the center string, the outer diameter of the injection string (and its accompanying packer) must be smaller than the inner diameter of the center string, and the container needs to be set inside the injection string, which will lead to severe limitations on the external dimensions of the container, and thus the capacity of the sealing agent it carries is very limited. Summary of the Invention

[0003] The purpose of the present invention is to overcome the defects of the prior art and provide a self-driven sealing pipe segment, a sealing method and a completion structure in the annulus of the production section of an oil and gas well, which can improve the anti-channeling ability of the continuous sealing body in the annulus of the wellbore of the production section of an oil and gas well and improve the crude oil recovery rate.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A self-driving solid sealing pipe segment in the annulus of an oil and gas well production section is used in oil and gas wells in a single formation or through multiple formations. A central pipe string is provided in the wellbore of the oil and gas well production section, and a wellbore annulus is defined between the wellbore wall of the production section wellbore and the central pipe string. A continuous sealing body formed by the accumulation of sealing particles is provided in the wellbore annulus; the central pipe string includes the self-driving solid sealing pipe segment, and the self-driving solid sealing pipe segment includes: a base pipe 1, which is a tubular structure as a whole, and is provided with docking devices 11 at both ends, which can be connected end to end with adjacent pipe segments in the central pipe string; a storage device 2, which is provided Placed on the base pipe 1, the storage device 2 is provided with a sealing agent 20 inside. Under the action of external drive, the storage device 2 can inject the sealing agent 20 into the wellbore annulus. The sealing agent 20 can enter the flow pores of the continuous sealing body and solidify, and form a sealing body 200 together with the continuous sealing body. The sealing body 200 can prevent the liquid in the wellbore annulus from flowing axially along the wellbore annulus; the driving device 3 is arranged on the base pipe 1, and is used to drive the storage device 2 to inject the sealing agent 20 into the wellbore annulus according to the injection trigger signal.

[0006] To achieve the above purpose, the present invention also adopts the following technical solutions:

[0007] A method for self-driving and sealing the annulus of an oil and gas well production section, using the self-driving and sealing pipe segment of the annulus of an oil and gas well production section as described above, comprises the following steps: (1) prefabricating a self-driving and sealing pipe segment carrying a sealing agent 20 on the central pipe string; wherein the position of the self-driving and sealing pipe segment relative to the central pipe string corresponds to the position of a target sealing point in the wellbore; (2) lowering the central pipe string into the wellbore; (3) the driving device drives the agent storage device to inject the sealing agent 20 into the wellbore annulus according to an injection trigger signal; (4) the sealing agent 20 enters the flow-through pores of the continuous sealing body in the wellbore annulus and solidifies, forming a sealing body 200 together with the continuous sealing body, wherein the sealing body 200 can prevent the liquid in the wellbore annulus from flowing axially along the wellbore annulus.

[0008] To achieve the above purpose, the present invention also adopts the following technical solutions:

[0009] A completion structure is used in oil and gas wells in a single formation or penetrating multiple formations. The completion structure includes a center tubing string arranged in the wellbore of the production section of the oil and gas well. A wellbore annulus is defined between the wellbore wall of the production section wellbore and the center tubing string. A continuous sealing body formed by the accumulation of sealing particles is provided in the wellbore annulus. It is characterized in that the center tubing string includes the self-driven solid sealing pipe section as described above.

[0010] The present invention provides a self-driven sealing pipe segment, sealing method and completion structure for the annulus of the production section of an oil and gas well. Compared with the existing method of using an injection string to perform fixed-point sealing, firstly, the self-driven sealing pipe segment is lowered into the production section of the wellbore together with the center string, which can reduce the operation steps of lowering the injection string separately and improve work efficiency; secondly, the external dimensions of the self-driven sealing pipe segment are basically consistent with those of other pipe segments in the center string, which can reduce the operational risk that the injection string cannot be lowered or lifted due to obstruction, and at the same time, it can also realize one-time completion operations for multiple target sealing points; thirdly, the position of the self-driven sealing pipe segment relative to the center string is fixed, which can realize accurate positioning of the target sealing position; fourthly, the self-driven sealing pipe segment has its own driving device, and there is no need to set a control driving cable on the center string. By adopting automatic control methods such as electronic or mechanical methods set in the device, the self-driving and self-control of the device operation can be realized, and the structure is simple and easy to use. Fifth, the capacity of the sealing agent can be preset in advance, so as to realize the injection and isolation of the quantitative sealing agent. While ensuring the isolation effect, it avoids injecting too much sealing agent to lose the oil-producing formation, and also avoids injecting too little sealing agent, which causes the sealing effect to fail to meet the expectations; Sixth, the trigger control method is adopted, which can cooperate with the completion operation process to accurately control the time of injecting the sealing agent, thereby improving the overall work efficiency of the completion operation; Seventh, it supports the use of two-component sealing agents to ensure that the solidification time of the sealing agent after being injected into the wellbore annulus can be accurately controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 2;

[0012] Figure 2 yes Figure 1 Middle cross-section along AA direction;

[0013] Figure 3 yes Figure 1 Middle cross-section along BB direction;

[0014] Figure 4 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 1 before the sealing agent is injected;

[0015] Figure 5 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 3;

[0016] Figure 6 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 3 after the sealing agent is discharged;

[0017] Figure 7 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 4;

[0018] Figure 8 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 4 after the sealing agent is discharged;

[0019] Figure 9 This is a cross-sectional view of the overall structure of another self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 4;

[0020] Figure 10 This is a cross-sectional view of the overall structure of another self-driving sealing pipe segment in the annulus of the production section of an oil and gas well in Example 4 after the sealing agent is discharged;

[0021] Figure 11 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 5;

[0022] Figure 12 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 5 after the sealing agent is discharged;

[0023] Figure 13 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 5;

[0024] Figure 14This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 5 after the sealing agent is discharged;

[0025] Figure 15 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section in Example 6;

[0026] Figure 16 yes Figure 15 Middle cross-section along AA direction;

[0027] Figure 17 yes Figure 15 Middle cross-section along BB direction;

[0028] Figure 18 yes Figure 15 Middle cross-section along CC direction;

[0029] Figure 19 This is a cross-sectional view of the overall structure of a self-driving sealing pipe segment in the annulus of an oil and gas well production section before glue filling in Example 6;

[0030] Figure 20 This is a schematic structural diagram of a well completion structure before sealing in Example 8;

[0031] Figure 21 This is a schematic structural diagram of a completion structure after sealing in Example 8.

[0032] Explanation of the reference numerals: 1-base tube, 11-docking device, 2-storage device, 20-sealing agent, 20-1-first sealing agent, 20-2-second sealing agent, 200-sealing body, 21-storage chamber, 22-piston, 221-sealing ring, 222-slider, 23-discharge connector, 231-filling port, 231-1-first filling port, 231-2-second filling port, 232-discharge port, 233-filter, 234-sealing agent mixing device, 24-pressure space, 25-partition, 26-storage capsule, 3-driving device, 31-control circuit, 32-battery, 33-driving device Drive motor, 34- plunger pump, 35- liquid inlet connector, 351- plunger pump liquid inlet channel, 352- plunger pump liquid outlet channel, 353- filling agent balance pressure port, 353-1- first filling agent balance pressure port, 353-2- second filling agent balance pressure port, 36- expansion material, 360- elastic force storage device, 361- limit device, 362- controller, 363- releaser, 37- liquid control valve, 4- pressure-bearing jacket, 41- electric control cabin, 42- electric cabin, 43- communication port, 44- extension fixing part, 45- elastic drive device cabin, 46- expansion material cabin, 5- self-driven solid sealing pipe joint. DETAILED DESCRIPTION

[0033] The following is combined with Figure 1-21, further describing the specific embodiments of the self-driving, solid-sealing pipe joint for isolating the wellbore annulus, the wellbore annulus isolation method, and the well completion structure of the present invention. The self-driving, solid-sealing pipe joint for isolating the wellbore annulus, the wellbore annulus isolation method, and the well completion structure of the present invention are not limited to the description of the following embodiments.

[0034] First, the application scenario of this patent is explained. For oil and gas wells that penetrate multiple formations, since the oil and water fronts of the multiple formations advance at different speeds after production, the oil and water fronts of the formation with the faster advancement speed will reach the wellbore position first, and this formation will become a high-water-content formation. For wellbores containing local high-water-content formations, since the mobility of water is much higher than that of oil, the produced water from the high-water-content formation will flow axially in the wellbore annulus to the adjacent formations at both ends, that is, interlayer crossflow. When the water reaches the production screen corresponding to the high-water-content formation and the adjacent formations at both ends, due to the superior mobility of water, a large amount of water will pass through the production screen into the center string and be produced, causing the water content in the produced fluid to increase sharply. On the other hand, due to the large amount of water produced, the internal and external pressure difference of the center string decreases, which will further inhibit the production of oil in the formation matrix. Therefore, in order to reduce the water content of the produced fluid and increase oil production, it is necessary to isolate the local high-water-content formation in the wellbore, especially to inhibit the crossflow of water in the wellbore annulus.

[0035] Example 1:

[0036] This embodiment provides a specific implementation method of a self-driving and sealing pipe joint in the annulus of a production section of an oil and gas well.

[0037] refer to Figure 1-19 As shown, a self-driving solid sealing pipe segment in the annulus of the production section of an oil and gas well is used in oil and gas wells in a single formation or through multiple formations. A central pipe string is provided in the wellbore of the production section of the oil and gas well, and a wellbore annulus is defined between the wellbore wall of the production section wellbore and the central pipe string. A continuous sealing body formed by the accumulation of sealing particles is provided in the wellbore annulus; the central pipe string includes the self-driving solid sealing pipe segment, and the self-driving solid sealing pipe segment includes: a base pipe 1, which is a tubular structure as a whole, and is provided with a docking device 11 at both ends, which can be connected end to end with the adjacent pipe segments in the central pipe string; a storage device 2, The agent storage device 2 is arranged on the base pipe 1, and a sealing agent 20 is provided inside the agent storage device 2. Under the action of external driving, the agent storage device 2 can inject the sealing agent 20 into the wellbore annulus. The sealing agent 20 can enter the flow pores of the continuous sealing body and solidify, and form a sealing body 200 together with the continuous sealing body. The sealing body 200 can prevent the liquid in the wellbore annulus from flowing axially along the wellbore annulus; the driving device 3 is arranged on the base pipe 1, and is used to drive the agent storage device 2 to inject the sealing agent 20 into the wellbore annulus according to the injection trigger signal.

[0038] Specifically, the base pipe 1 can be in the form of a conventional short section or a screen pipe, with the reservoir 2 and drive device 3 positioned in the blind section of the screen pipe. Different lengths of base pipe 1 can be preset to accommodate different target sealing points, providing greater flexibility in use. The diameter of the self-driving sealing section is consistent with the outer diameter of other sections of the central pipe string, such as the screen pipe, thereby effectively preventing the central pipe string from encountering obstructions during lowering. The length of each section of the self-driving sealing section can be adjusted based on the required capacity of the sealing agent 20 stored within the reservoir 2 and the space occupied by the drive device 3, thus meeting the requirements for larger volumes of sealing agent 20. The docking device 11 can refer to existing pipe string structures and adopt existing threaded or clamping methods. The position of the self-driving sealing section in the central pipe string is consistent with the position of the target sealing point (e.g., on both sides of a high-water-content formation, or at several locations in a longer formation production section that require isolation). The wellbore structure of the central pipe string can be planned and designed based on well logging data before the central pipe string is lowered into the well. Among them, the target sealing point refers to the location point in the wellbore of the oil and gas well that needs to be sealed, which is pre-set by the user according to the downhole formation conditions. After the central pipe string is lowered into the well, the sealing operation is performed through the self-driven sealing pipe section, and the wellbore annulus can be sealed by the sealing agent 20 at the target sealing point position, thereby achieving, for example, the isolation of the high water-containing formation from other formations. The injection trigger signal refers to a signal that guides the driving device 2 to drive the storage device 2 to inject the sealing agent 20 into the wellbore annulus. The injection trigger signal can be generated in a variety of ways, such as being sent from the ground through a control line connected to the ground, or using a pressure control method. For example, after the central pipe string is lowered into the well and reaches the corresponding formation, it will be subjected to the pressure generated by the underground fluid, and the injection trigger signal is generated by identifying the pressure value; for example, the downhole pressure is increased manually from the wellhead to the central pipe string or the wellbore by injection, and the injection trigger signal is generated by identifying the pressure value. The sealing agent 20 can be in the form of a self-setting glue, and the time from the completion of configuration to the solidification can be set to 8 to 48 hours according to the completion operation process; the sealing agent 20 can also be made of a liquid-deforming material, for example, it can react with the downhole liquid to block the flow-through pores of the continuous sealing body; the sealing agent 20 can also be made of a soluble material, for example, it can dissolve the sealing particles that form the continuous sealing body, so that the sealing particles are melted into a whole, thereby eliminating its flow-through pores.

[0039] As an optional implementation, the injection trigger signal is generated by a trigger disposed inside the driving device 3 .

[0040] Specifically, since the center pipe string will involve operations such as well washing and filling the wellbore annulus with sealing particles after being lowered into the well, it is necessary to accurately control the time for injecting the sealing agent 20 into the self-driving sealing pipe segment to ensure the operation sequence between different processes. The trigger can adopt an electronic or mechanical timer, and its specific structure and implementation method can refer to the existing technology. The advantage of adopting the solution proposed in this embodiment is that, compared with the control line method connected to the ground, there is no need to lay the control line, which is not only low in cost, but also avoids the occurrence of sealing failure caused by damage to the control line during the downhole process; compared with the pressure control method, more precise control can be achieved, and the operation is simple and cost-saving. Since the self-driving sealing pipe segment proposed in this embodiment has its own driving device 3 and trigger (timer), it can achieve "automatic driving" or "self-driving" after being lowered into the well, and the "self-driving" in the name of this patent can be achieved.

[0041] As an optional embodiment, the self-driven sealed pipe segment also includes a pressure-bearing jacket 4, which is a cylindrical structure and is arranged on the outside of the base pipe 1; the storage device 2 and the driving device 3 are arranged in the pipe segment annulus formed by the inner wall of the pressure-bearing jacket 4 and the outer wall of the base pipe 1.

[0042] Specifically, the outer diameter of the pressure-bearing outer sleeve 4 is consistent with the outer diameter of the screen pipe, or is smaller than the diameter of the screen pipe, so as to ensure that the central pipe string will not encounter obstructions due to the excessive outer diameter of the self-driven sealing pipe segment during the downhole process. Preferably, the pressure-bearing outer sleeve 4 is coaxially arranged with the base pipe 1, so that the pipe segment annulus formed is a standard annulus structure, which is convenient for arranging other components inside it. The pressure-bearing outer sleeve 4 can be an integrated structure or a structure composed of multiple sleeves. Its function is to form a storage device 2, install and protect the drive device 3 and other related devices. Of course, the pressure-bearing outer sleeve 4 is not limited to a standard cylindrical structure, and can also be combined with the base pipe 1 to form other shapes. For example, an axial partition is arranged inside the base pipe to divide the inside of the base pipe 1 into two spaces, one of which is used as a liquid production channel and the other as a pipe segment annulus. The technical effect it plays is the same as that of this embodiment, and it should be considered to belong to the same technical solution as this embodiment.

[0043] The device operates as follows: first, a sealing agent 20 is provided on the surface and placed in the reservoir 2. The self-propelled sealing pipe segments are then assembled into a central string and lowered into a predetermined position in the wellbore production section. The drive device 3, in response to an injection trigger signal, drives the reservoir 2 to inject the sealing agent 20 into the wellbore annulus. The sealing agent 20 enters the flow-through pores of the continuous packer in the wellbore annulus and solidifies, forming a sealing body 200 together with the continuous packer. The sealing body 200 is capable of preventing the liquid in the wellbore annulus from flowing axially along the wellbore annulus.

[0044] It should be further explained that Example 1 proposes an overall implementation method of a self-driven sealing pipe segment in the annulus of an oil and gas well production section, and the following Examples 2 to 6 are more specific visual methods proposed based on the inventive concept of Example 1. These embodiments can be used to illustrate each other and combined with each other to form further technical solutions.

[0045] Example 2:

[0046] Based on the above embodiments, this embodiment provides a specific implementation method of a self-driving sealing pipe joint in the annulus of a production section of an oil and gas well.

[0047] like Figure 1-4 As shown, as an optional embodiment, the storage device 2 includes a storage chamber 21 defined by a portion of the inner wall of the pressure-bearing jacket 4 and a portion of the outer wall of the base pipe 1, and the storage chamber 21 is provided with a piston 22 at one end close to the driving device 3, and a discharge joint 23 at the other end; wherein, the piston 22 is a circular ring structure as a whole, and the inner ring surface and the outer ring surface are respectively slidably sealed with the outer wall of the base pipe 1 and the inner wall of the pressure-bearing jacket 4, and can move in the axial direction inside the storage chamber 21 under the driving force of an external force; the discharge joint 23 connects and fixes the end of the pressure-bearing jacket 4 to the base pipe 1, and closes the end of the storage chamber 21; a filling port 231 and a discharge port 232 are provided inside the discharge joint 23, which are respectively used to fill the sealing agent 20 into the storage chamber 21 and discharge the sealing agent 20 from the storage chamber 21.

[0048] Specifically, the storage tank 21 is used to store the sealing agent 20. According to the well logging data of the target sealing point and the distance of the wellbore to be sealed, the sealing agent 20 of a suitable capacity can be pre-placed in the storage tank in advance, without the requirement to fill the entire tank with the sealing agent 20; and, when the capacity of the entire tank sealing agent 20 cannot meet the sealing requirements of a certain target sealing point, a longer self-driving sealing pipe section can be selected to obtain a larger sealing agent capacity, or two or more self-driving sealing pipe sections can be used in series to coordinate the work. Preferably, a sealing ring 221 can be provided on the inner and outer annular surfaces of the piston 22 in contact with part of the inner wall of the pressure-bearing jacket 4, and part of the outer wall of the base pipe 1, so as to improve the sealing effect of the piston 22. The piston 22 can be made of a hard structure such as metal, a soft rubber or nylon structure, or a rubber / nylon wrapped metal structure, etc., as long as it plays a sealing role and a reciprocating motion function, it can meet the needs. The function of the piston 22 is to seal the end of the storage chamber 21 and change the volume of the storage chamber 21, thereby realizing the filling or removal of the sealing agent 20 into the storage chamber 21. The discharge joint 23 is an annular structure as a whole, and its functions include three aspects: first, it is used to support and fix the end of the pressure-bearing jacket 4; second, it is sealed with the end of the pressure-bearing jacket 4 and the base pipe 1, thereby forming a closed storage chamber 21; third, it has a filling port 231 and a discharge port 232 formed inside it to realize the filling and discharge functions. Figure 1 and Figure 4 , respectively, are schematic diagrams of the self-driving sealing pipe section to be discharged after the sealing agent 20 is lowered into the well and the schematic diagram of the sealing agent 20 to be injected before the self-driving sealing pipe section is lowered into the well. Preferably, a one-way valve can be set in the injection port 231 and the discharge port 232 to ensure that the sealing agent 20 can only be injected into the well. Figure 1 、 Figure 4 The sealing agent 20 flows in the direction of the middle arrow, thereby removing the sealing agent 20 from the wellbore annulus, or injecting the sealing agent 20 into the storage chamber 21. Preferably, the outlet 232 can be evenly arranged in multiple numbers (for example, 3 or 4) along the circumferential direction, so as to achieve circumferentially uniform injection of the sealing agent into the wellbore annulus. Preferably, a filter screen 233 can also be provided on the outlet 232 to prevent particles in the wellbore annulus from entering the outlet 232. After the sealing agent 20 is injected into the wellbore annulus, it will enter the flow pores of the continuous isolation body and solidify, thereby isolating the wellbore annulus at that position and preventing liquid from passing through the wellbore annulus area, thereby enhancing the sealing capacity of the wellbore annulus and improving the oil well recovery rate.

[0049] As an optional embodiment, the driving device 3 includes a control circuit 31, a battery 32, a driving motor 33 and a plunger pump 34, wherein a trigger is provided inside the control circuit 31 for generating an injection trigger signal at a specified time according to user settings; or, a pressure detection device is provided inside the control circuit 31 for detecting the pressure wave generated by ground filling and generating an injection trigger signal according to the pressure wave; and the control circuit 31 also controls the operation of the driving motor 33 according to the injection trigger signal; the battery 32 is used to supply power to the control circuit 31; the driving motor 33 is used to accept the control of the control circuit 31 and drive the plunger pump 34 to operate; the plunger pump 34 is used to accept the drive of the driving motor 33 to inject the liquid in the wellbore annulus into the closed pressure space 24 on the side of the piston 22 away from the agent outlet joint 23, and drive the piston 22 to move in the direction of the agent outlet joint 23, thereby discharging the sealing agent 20 in the storage chamber 21 through the agent outlet 232.

[0050] Specifically, the control circuit 31 can adopt an embedded system structure such as a single-chip microcomputer. The system is started before the central pipe string is lowered into the well. The control circuit 31 receives the trigger parameters set by the user. The trigger is an electronic timer set inside the embedded system. The electronic timer performs timing / counting in the form of relative time values (for example, 8 hours later) or absolute time values (for example, XXXX year XX month XX day XX hour XX minute). After the central pipe string is lowered into the well, when the preset time is reached, the trigger inside the control circuit 31 generates an injection trigger signal, and the control circuit 31 starts the drive motor 33 to run, thereby driving the plunger pump 34 to run; and preferably, when the drive motor 33 runs for a certain period of time and the sealing agent 20 is completely injected into the wellbore annulus, the control circuit 31 stops the drive motor 33. As an optional method for generating an injection trigger signal, the trigger is not a timer, but a pressure sensor assembly logically located on the control circuit 31. The pressure sensor assembly can be mounted on the circuit board of the control circuit 31 or elsewhere in the device via leads. Its function is to detect downhole pressure. For example, when a certain pressure value is detected, the center string is considered to have reached a predetermined position, or when a certain pressure value is detected at the wellhead, the trigger condition is considered to have been met. The embedded system generates an injection trigger signal based on this pressure value and a preset program, which activates the plunger pump 34 with or without a certain delay. The control circuit 31, battery 32, drive motor 33, and plunger pump 34 can adopt specific structures known in the art, and should use corresponding components that can adapt to the high temperature and high pressure conditions downhole.

[0051] As an optional embodiment, the driving device 3 also includes a liquid inlet joint 35, which is fixedly and sealedly connected to the pipe segment annulus, and the liquid inlet joint 35, the piston 22, the inner wall of the pressure-bearing sleeve 4, and the outer wall of the base pipe 1 define a closed pressure space 24; a plunger pump liquid inlet channel 351 and a plunger pump liquid outlet channel 352 are provided inside the liquid inlet joint 35, wherein the plunger pump liquid inlet channel 351 connects the liquid inlet of the plunger pump 34 and the wellbore annulus; the plunger pump liquid outlet channel 352 connects the liquid outlet of the plunger pump 34 and the closed pressure space 24.

[0052] Specifically, the liquid inlet connector 35 has three functions: first, the pressure-bearing jacket 4 adopts a split design, that is, Figure 1 The left side is used to form the part of the storage chamber 21, and the right side is used to form the part of the electric control chamber 41 and the electric chamber 42. The liquid inlet joint 35 is used to support and fix the right side of the pressure-bearing jacket 4 corresponding to the storage chamber 21, and the left side of the pressure-bearing jacket 4 corresponding to the electric control chamber 41; secondly, it is sealed with the pressure-bearing jacket 4 and the base pipe 1 to form the storage chamber 21, the closed pressure space 24, the electric control chamber 41 and other structures; thirdly, the internal forming plunger pump inlet channel 351 and plunger pump outlet channel 352, the filling agent balance pressure port 353 and other structures. Among them, the plunger pump inlet channel 351 and the plunger pump outlet channel 352 can be provided with a one-way valve to ensure that the sealing agent can only be filled according to the flow of liquid. Figure 1 、 Figure 4 The liquid flows in the direction of the arrow. The filling balance pressure port 353 is used to exhaust air from the enclosed pressure space 24 to ensure pressure balance when the sealing agent 20 is filled into the storage chamber 21. It should be further explained that the pressure space 24 and the storage chamber 21 are not named for absolute positions in the device, but are named from a functional perspective. The physical space areas of the two overlap, and their spatial size changes synchronously with the movement of the piston.

[0053] As an optional embodiment, the side of the pipe segment annulus formed by the inner wall of the pressure-bearing jacket 4 and the outer wall of the base pipe 1 away from the storage chamber 21 also includes an electric control cabin 41 and an electric cabin 42, and the axial ends of the electric control cabin 41 and the electric cabin 42 are defined and sealed by the extension fixing portion 44 of the end of the pressure-bearing jacket 4 toward the base pipe 1, and the liquid inlet joint 35; wherein the electric control cabin 41 is used to set the control circuit 31 and the battery 32 for powering the control circuit 31; the electric cabin 42 is used to set the drive motor 33 and the plunger pump 34.

[0054] Specifically, by placing components such as the control circuit 31, battery 32, drive motor 33, and plunger pump 34 in a sealed electric control cabin 41 and electric cabin 42, the safety and reliability of the relevant components during the downhole process are ensured to prevent damage, and contact corrosion of the downhole production fluid is avoided to ensure that they can be recycled and reused. Preferably, a communication port 43 is also provided on the extended fixing portion 44, and the communication port 43 is electrically connected to the control circuit 31. Before the self-driven sealing pipe section is lowered into the well, it is used to send information such as trigger parameters to the control circuit 31 through the communication port 43. The electric control cabin 41 and the electric cabin 42 can be distributed front to back or side by side along the axial direction, and this patent does not limit this.

[0055] This embodiment adopts the technical solution of outputting the sealing agent 20 by electronically controlled drive and piston drive. Firstly, by presetting the trigger timing parameters, the time and duration of outputting the sealing agent 20 can be accurately controlled. At the same time, the output power of the plunger pump 34 can also be accurately controlled, thereby accurately controlling the rate and amount of discharge of the agent to avoid incomplete discharge of the agent. Secondly, the electronically controlled drive structure technology is relatively mature, with high reliability and low overall cost.

[0056] Example 3:

[0057] Based on the above embodiments, this embodiment provides a specific implementation method of a self-driving sealing pipe joint in the annulus of a production section of an oil and gas well.

[0058] like Figure 5-6 As shown, as an optional embodiment, the driving device 3 includes an elastic force storage device 360, a limit device 361, a controller 362 and a releaser 363, wherein the controller 362 is internally provided with a trigger for generating an injection trigger signal at a specified time according to a user setting, and controlling the releaser 363 to release the limit device 361 according to the injection trigger signal; the releaser 363 is used to accept the control of the controller 362 and release the limit device 361; one end of the elastic force storage device 360 is fixed, and the other end is a free end, and the free extension direction of the free end points to the piston 22; see Figure 5 The elastic force storage device 360 is in a compressed state in the initial state, and its extension is limited by the limiting device 361; see Figure 6 When the limiting device 361 is released by the releaser 363, the free end of the elastic force storage device 360 extends outward and drives the piston 22 to move toward the agent outlet connector 23, thereby discharging the sealing agent 20 in the storage chamber 21 through the agent outlet 232.

[0059] Specifically, the only difference between this embodiment and Example 2 lies in the structure of the drive device 3. For other unexplained portions, please refer to Example 2. The elastic force storage device 360 utilizes the elasticity of a metal or other material to store energy, which is used to push the piston 22 to expel the sealing agent 22. The elastic force storage device 360 can be a circular spring or a structure such as memory metal. The controller 362 can be electronic or mechanical, as detailed below. The releaser can also be electrically controlled or mechanical. For example, referring to the technical principles of disclosed solutions such as Chinese Patents 2023219510180 and 2020115538277, the releaser uses circuit drive and electromagnetic release. For another example, referring to the technical principles of disclosed solutions such as Chinese Patent 2020103202316, energy is stored by a spring or spring to drive a mechanical release mechanism. The energy stored in the elastic force storage device 360 should be sufficient to push the piston 22 to its furthest point, thereby ensuring that all the sealing agent 20 is expelled.

[0060] As an optional implementation, the trigger provided in the controller 362 is an electronic timer or a mechanical timer.

[0061] Specifically, the trigger provided within the controller 362 is an electronic timer. Similarly, referring to Chinese Patents 2023219510180 and 2020115538277, this can be a self-powered embedded system with an internal electronic timer. The trigger can also be a mechanical timer, such as a spring-driven gear system. When the timing period is reached, the electronic timer generates an electronic injection trigger signal, which is transmitted to the controller 362. Alternatively, the mechanical timer generates a component action as the injection trigger signal, which acts as the release action of the releaser 363, or the component action triggers the release action of the releaser 363.

[0062] As an optional embodiment, the side of the pipe segment annulus formed by the inner wall of the pressure-bearing sleeve 4 and the outer wall of the base pipe 1 facing away from the storage chamber 21 also includes an elastic drive device cabin 45, and the axial ends of the elastic drive device cabin 45 are defined and sealed by the extension fixing portion 44 of the end of the pressure-bearing sleeve 4 toward the base pipe 1, and the liquid inlet joint 35; the elastic force storage device 360, the limit device 361, the controller 362 and the releaser 363 are arranged in the elastic drive device cabin 45.

[0063] Specifically, by placing the elastic force storage device 360, limiter 361, controller 362, and releaser 363 within the elastic drive device compartment 45, the safety and reliability of the relevant components during the downhole operation are ensured, preventing damage. Furthermore, contact corrosion with downhole production fluids is avoided, ensuring that the fluid can be recycled and reused. Preferably, the extended fixed portion 44 is also provided with a communication port 43, which allows the user to set the timer parameters within the controller 362 before the center string is lowered into the well. This can be done electronically or mechanically.

[0064] As an optional implementation, the elastic force storage device 360 is a spring structure.

[0065] Specifically, the energy stored in the elastic force storage device 360 should be able to push the piston 22 to the farthest section, thereby ensuring that the sealing agent 20 can be completely discharged.

[0066] This embodiment utilizes an elastic force storage device 360 to drive and piston-driven sealant 20 output. Compared to the electronic control solution disclosed in Example 2, this solution avoids bringing batteries, circuit boards, and other structures underground, thus reducing contamination. Furthermore, the purely mechanical drive device 3 offers improved reliability and lower costs, making it ideally suited for use in underground environments during oil and gas well production.

[0067] Example 4:

[0068] Based on the above embodiments, this embodiment provides a specific implementation method of a self-driving sealing pipe joint in the annulus of a production section of an oil and gas well.

[0069] like Figure 7-10 As shown, as an optional embodiment, the storage device 2 is a storage bag 26, and the storage bag 26 is arranged in a storage chamber 21 defined by part of the inner wall of the pressure-bearing jacket 4 and part of the outer wall of the base pipe 1, and the mouth of the storage bag 26 is connected to a discharge joint 23; the discharge joint 23 connects and fixes the end of the pressure-bearing jacket 4 to the base pipe 1, and closes the end of the storage chamber 21; a discharge port 232 is provided inside the discharge joint 23 for discharging the sealing agent 20 from the storage bag 26.

[0070] Specifically, the difference between this embodiment and embodiment 2 is only that the structure of the agent storage device 2 is different. For other parts not described, please refer to embodiment 2. According to the technical solution disclosed in embodiment 2, when the user uses the self-driving sealing pipe section disclosed in embodiment 2, it is necessary to inject the sealing agent 20 into the agent storage chamber 21 on site on the well, which will inevitably affect the construction efficiency and extend the construction period. In this embodiment, the agent storage device 2 is an agent storage capsule 26, which can be considered to be based on the agent storage chamber 21 disclosed in embodiment 2, with one or more agent storage capsules 26 arranged in the space of the agent storage chamber 21. The agent storage capsule 26 can be a rubber structure, such as a rubber capsule; or it can be a soft metal structure, such as a structure similar to a toothpaste tube. At the same time, the opening of the agent storage capsule 26 is connected to the agent outlet connector 23. Its principle and implementation method are shown in embodiment 2. The technical effect of this embodiment is that the user can prefabricate the reservoir capsule 26 in a non-oil and gas well site environment such as a factory, for example, to produce it in the form of a toothpaste with a toothpaste cover (cover body) structure. When used on site, the reservoir capsule 26 is directly loaded into the space of the reservoir chamber 21, and then the cover body is removed and the opening is connected to the agent outlet joint 23 to complete the preparation work for going down the well, thereby improving work efficiency and avoiding omission or contamination of the sealing agent during the on-site injection process. Figure 7 As shown in FIG, it is a schematic diagram of the present embodiment before the sealing agent 20 is discharged. Figure 8 The figure shows the state of this embodiment after the sealing agent 20 is discharged. At this time, the storage capsule 26 can be compressed near the discharge connector 23 under the pressure of the fluid, or it can be naturally deflated and accommodated in the storage chamber 21. When implementing this technical solution, some sealing agent 26 may eventually remain inside the storage capsule 26, but this will not affect the final sealing effect.

[0071] like Figure 7-8 As shown, as an optional embodiment, the driving device 3 includes a control circuit 31, a driving motor 33 and a plunger pump 34, wherein a trigger is provided inside the control circuit 31 for generating an injection trigger signal at a specified time according to user settings; or, a pressure detection device is provided inside the control circuit 31 for detecting the pressure wave generated by ground filling and generating an injection trigger signal according to the pressure wave; and the control circuit 31 also controls the operation of the driving motor 33 according to the injection trigger signal; the driving motor 33 is used to accept the control of the control circuit 31 and drive the plunger pump 34 to operate; the plunger pump 34 is used to accept the drive of the driving motor 33 and inject the liquid in the wellbore annulus into the storage chamber 21, thereby discharging the sealing agent 20 in the storage bag 26 through the outlet 232.

[0072] Specifically, the structure and operating principle of the driving device 3 are consistent with those of Example 2, differing only in the process by which the plunger pump 34 drives the sealing agent 20 to be discharged. In this embodiment, since the reservoir 21 is a sealed space, when the plunger pump 34 pumps liquid into the reservoir 21, the internal pressure of the reservoir 21 increases and is transmitted to the reservoir capsule 26, thereby compressing the reservoir capsule 26 and discharging the sealing agent 20 therein.

[0073] like Figure 9-10 As shown, as an optional embodiment, the driving device 3 includes an elastic force storage device 360, a limiting device 361, a controller 362 and a releaser 363, wherein the controller 362 is internally provided with a trigger for generating an injection trigger signal at a specified time according to user settings, and controlling the releaser 363 to release the limiting device 361 according to the injection trigger signal; the releaser 363 is used to accept the control of the controller 362 and release the limiting device 361; one end of the elastic force storage device 360 is fixed, and the other end is a free end, and the free extension direction of the free end points to the storage capsule 26; the elastic force storage device 360 is in a compressed state in the initial state, and its extension is limited by the limiting device 361; when the limiting device 361 is released by the releaser 363, the free end of the elastic force storage device 360 extends toward the storage capsule 26 and squeezes the storage capsule 26, thereby discharging the sealing agent 20 in the storage capsule 26 through the outlet 232.

[0074] Specifically, this embodiment employs a purely mechanical solution, wherein the sealing agent 20 is stored in a reservoir 26 and discharged via an elastic force storage device 360. This solution can be considered a combination of the various specific partial technical solutions described above, and thus achieves the technical effects achieved by the corresponding partial technical solutions. For details regarding the structure and operating principle, please refer to the aforementioned description.

[0075] like Figure 9-10 As shown, as an optional embodiment, a slider 222 is further provided between the storage bag 26 and the driving device 3. The slider 222 is an annular structure as a whole, and the inner and outer annular surfaces are respectively slidably fitted with the outer wall of the base pipe 1 and the inner wall of the pressure-bearing jacket 4. Under the drive of the driving device 3, it can move in the axial direction inside the storage chamber 21; thereby, the sealing agent 20 is discharged from the storage bag 26.

[0076] Specifically, during the actuation process, the elastic force storage device 360 directly contacts the reservoir 26, potentially puncturing it or failing to effectively compress it. Therefore, a slider 222 is provided between the elastic force storage device 360 and the reservoir 26. This slider transmits the driving force of the elastic force storage device 360 to the reservoir 26, thereby more thoroughly discharging the sealing agent 20 in the reservoir 26 into the wellbore annulus while protecting the reservoir 26 from puncture.

[0077] This embodiment adopts a technical solution of storing the sealing agent 20 through a storage capsule 26. The user can pre-place the sealing agent 20 in the storage capsule 26 in advance outside the site, which is convenient for large-scale production, storage and transportation; at the same time, the storage capsule 26 pre-placed with the sealing agent 20 can be used as a component at the construction site, thereby improving the on-site construction efficiency.

[0078] Example 5:

[0079] Based on the above embodiments, this embodiment provides a specific implementation method of a self-driving sealing pipe joint in the annulus of a production section of an oil and gas well.

[0080] like Figure 11-14 As shown, as an optional embodiment, the side of the pipe segment annulus formed by the inner wall of the pressure-bearing sleeve 4 and the outer wall of the base pipe 1 away from the storage chamber 21 also includes an expansion material chamber 46, and the end of the expansion material chamber 46 axially away from the storage device 2 is defined and sealed by the extension fixing portion 44 of the end of the pressure-bearing sleeve 4 toward the base pipe 1, and the storage device 2 is connected; the driving device 3 includes an expansion material 36 arranged in the expansion material chamber 46; the volume of the expansion material 36 increases after expansion, driving the storage device 2 to inject the sealing agent 20 into the wellbore annulus.

[0081] Specifically, the expansion material chamber 46 and the expansion material 36 pre-placed therein disclosed in this embodiment can be considered as another specific structure of the driving device 3, and its function is the same as that of the driving device 3 disclosed in the above embodiment, that is, providing driving force so that the sealing agent 20 is injected into the wellbore annulus. More specifically, as Figure 11-12 As shown, it is a technical solution that combines the expansion material 36 with the storage capsule 26; Figure 13-14 As shown, this embodiment utilizes an expansion material 36 combined with a storage chamber 21. This demonstrates that this embodiment also combines the various specific partial technical solutions described above, thus achieving the same technical effects as those provided by the corresponding partial technical solutions. For details regarding the structure and operating principle, please refer to the aforementioned description.

[0082] like Figure 11-14As shown, as an optional embodiment, the expansion material 36 is a liquid-expandable material; the driving device 3 also includes a liquid-expandable control valve 37 arranged on the outer wall of the expansion material cabin 46, and a trigger is provided inside the liquid-expandable control valve 37 for generating an injection trigger signal at a specified time according to user settings; or, a pressure detection device is provided inside the liquid-expandable control valve 37 for detecting the pressure wave generated by ground filling and generating an injection trigger signal according to the pressure wave; and the liquid-expandable control valve 37 also opens the valve body according to the injection trigger signal to achieve contact between the liquid in the wellbore annulus and the expansion material 36.

[0083] Specifically, the expansion material 36 is a liquid-expandable material. When it comes into contact with the downhole liquid, it can expand, thereby driving the sealing agent 20 to be injected into the wellbore annulus. In order to achieve contact between the expansion material 36 and the downhole liquid, the outer wall of the expansion material chamber 46 is provided with one or more through holes penetrating the outer wall. The through holes are provided with a liquid control valve 37, which is used to allow the liquid in the wellbore to enter the expansion material chamber 46 and come into contact with the expansion material 36. Preferably, the liquid control valve 37 can adopt multiple control methods: first, the liquid control valve 37 adopts an electronic control structure, a timer is provided on the main control circuit board or in the embedded system as a trigger, and a solenoid valve or other electronically controlled valve is also provided as the valve body; second, the liquid control valve 37 adopts a mechanical structure, such as a pressure crushing disc. The user injects pressure into the wellbore from the ground. When the applied pressure exceeds the crushing pressure of the pressure-breaking disc, it compresses it, allowing the liquid in the wellbore to enter the expansion material chamber 46. A third method is to use a soluble structure, such as liquid-soluble rubber, with a user-selectable dissolution time (e.g., 8 hours). When the liquid-soluble rubber liquid-soluble control valve 37 is lowered into the wellbore and encounters the wellbore liquid, it begins to dissolve. After the set dissolution time is reached, it no longer hinders the fluid in the wellbore from entering the expansion material chamber 46.

[0084] As an optional embodiment, the expansion material 36 is a self-expanding material; the starting expansion time of the self-expanding material is 1-24 hours after the self-driving sealing pipe joint is lowered into the well, and the expansion time of the self-expanding material is 1-48 hours.

[0085] Specifically, the expansion material cabin 46 is a self-expanding material, which is configured on site by the user and pre-set in the expansion material cabin 46. The self-expanding material begins to expand after being lowered into the well and reaching the starting expansion time, and drives the sealing agent 20 to be gradually injected into the wellbore annulus; when the expansion time of the self-expanding material is reached, the preset sealing agent 20 is completely or almost completely injected into the wellbore annulus.

[0086] In this embodiment, by using expansion material 36 as a component for generating driving force of the driving device 3, its structure is simpler than that of the driving devices 3 of other structures mentioned above. It is composed of only an expansion material compartment 46 of a shell structure and a single-component expansion material 36. Obviously, it can have a more stable and reliable driving effect, and the cost will be lower.

[0087] Example 6:

[0088] Based on the above embodiments, this embodiment provides a specific implementation method of a self-driving sealing pipe joint in the annulus of a production section of an oil and gas well.

[0089] like Figure 15-19 As shown, as an optional embodiment, the number of the storage devices 2 is two; the two storage devices 2 share a common outlet 232, and the outlet 232 is provided with a sealing agent mixing device 234; the two storage devices 2 are respectively provided with one component sealing agent of the two-component sealing agent.

[0090] Specifically, since there may be a certain pressure difference between different strata, if the solidification time of the sealing agent 20 is too slow, it will flow slowly under the drive of the pressure difference, making it difficult to solidify it at the target sealing point. In actual construction, it often takes dozens of hours from the time the sealing agent 20 is poured into the storage tank 21 to the time the central pipe string is completely lowered into the wellbore production section. Therefore, it is impossible to use a sealing agent with a faster solidification time. For this reason, this embodiment provides a technical solution using a two-component sealing agent 20. Refer to the attached Figure 15-19 , a partition 25 is axially provided inside the storage chamber 21, and the partition 25 separates the storage chamber 21 into two independent spaces for respectively accommodating the first sealing agent 20-1 and the second sealing agent 20-2 of different components. At the same time, the two independent spaces are also provided with independent first filling port 231-1, second filling port 231-2, and first filling balance pressure port 353-1, second filling balance pressure port 353-2. And the corresponding piston 22 is also split into two, respectively adapted to the two independent spaces. According to Figure 15-19As shown, the driving device 3 can share a set of systems. Of course, a driving motor 33 and / or a plunger pump 34 can also be set separately on the basis of a set of control circuits 31 as the main control, so as to realize the independent drive discharge of the two components of the sealing agent 20. It should be noted that the partition 25 does not necessarily isolate the storage chamber 21 into two independent spaces of the same size. The space design can refer to the component composition of the two-component sealing agent. For example, when the ratio of the two components is 1:2, the partition can be set at 120 degrees and 240 degrees in the circumferential direction. The advantage of using two components is that the construction process is no longer subject to the constraints of the solidification of the sealing agent 20, and the work efficiency is improved. For example, when the two components are set independently, the fluid state can be maintained for a long time (for example, one month or longer). After the two components are mixed underground, they can be solidified and fixed within a short time (for example, 10 minutes to 100 minutes).

[0091] It should be further explained that the present embodiment Figure 15-19 This is an improvement based on the attached drawings of Example 2. For Examples 3-5, those skilled in the art will find that Figure 15-19 Under the guidance of , the technical solutions given in Examples 3-5 can be improved to form technical solutions suitable for the two-component sealing agent 20. These technical solutions can be directly implemented by those skilled in the art and should be deemed to fall within the scope of protection of this patent.

[0092] Example 7:

[0093] Based on the above embodiments, this embodiment provides a specific implementation method of a self-driving sealing method for the annulus of a production section of an oil and gas well.

[0094] A method for self-driving and sealing the annulus of an oil and gas well production section, using a self-driving and sealing pipe segment of the annulus of an oil and gas well production section as described in any one of Examples 1-6, comprising the following steps: (1) prefabricating a self-driving and sealing pipe segment carrying a sealing agent 20 on the central pipe string; wherein the position of the self-driving and sealing pipe segment relative to the central pipe string corresponds to the position of a target sealing point in the wellbore; (2) lowering the central pipe string into the wellbore; (3) the driving device drives the agent storage device to inject the sealing agent 20 into the wellbore annulus according to an injection trigger signal; (4) the sealing agent 20 enters the flow-through pores of the continuous sealing body in the wellbore annulus and solidifies, forming a sealing body 200 together with the continuous sealing body, wherein the sealing body 200 can prevent the liquid in the wellbore annulus from flowing axially along the wellbore annulus.

[0095] Specifically, the method disclosed in this embodiment adopts the apparatus disclosed in Examples 1-6. For further method steps and technical effects achieved, please refer to the description of Examples 1-6.

[0096] Example 8:

[0097] Based on the above embodiments, this embodiment provides a specific implementation of a well completion structure.

[0098] like Figure 20-21 As shown, a completion structure is used in oil and gas wells in a single formation or through multiple formations. The completion structure includes a center tubing string arranged in the wellbore of the production section of the oil and gas well, and a wellbore annulus is defined between the wellbore wall of the production section wellbore and the center tubing string. A continuous sealing body formed by the accumulation of sealing particles is provided in the wellbore annulus; it is characterized in that the center tubing string includes a self-driven solid sealing pipe segment 5 as described in any one of Examples 1-6.

[0099] Specifically, such as Figure 20 As shown, this is the state when the self-driving sealing pipe segment 5 is lowered into the wellbore production section and the sealing agent 5 is not discharged; Figure 21 The figure shows the state of the self-driving sealing pipe segment 5 after the sealing agent 5 is discharged. As can be seen in the figure, the sealing agent 5 forms a sealing body 200 in the wellbore annulus.

[0100] The well completion structure disclosed in this embodiment adopts the device disclosed in Examples 1-6. For further structure and technical effects achieved, please refer to the description of Examples 1-6.

[0101] The above is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A self-driven sealing pipe joint for the annulus of an oil and gas well production section, which is used in oil and gas wells in a single formation or in oil and gas wells that penetrate multiple formations. A central pipe string is provided in the wellbore of the oil and gas well production section, and a wellbore annulus is defined between the wellbore wall of the production section wellbore and the central pipe string. A continuous sealing body formed by the accumulation of sealing particles is provided in the wellbore annulus; the characteristics are: The central pipe string includes the self-driving and sealing pipe section, and the self-driving and sealing pipe section includes: The base pipe is a tubular structure with docking devices at both ends, which can be connected end to end with the adjacent pipe sections in the central pipe string; A reservoir device is provided on the base pipe, wherein a sealing agent is provided inside the reservoir device. Under the action of an external drive, the reservoir device can inject the sealing agent into the wellbore annulus. The sealing agent can enter the flow-through pores of the continuous packer and solidify to form a sealing body together with the continuous packer. The sealing body can prevent the liquid in the wellbore annulus from flowing axially along the wellbore annulus. The driving device is arranged on the base pipe and is used to drive the agent storage device to inject the sealing agent into the wellbore annulus according to the injection trigger signal.

2. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 1 is characterized in that: The injection trigger signal is generated by a trigger arranged inside the driving device.

3. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 2 is characterized in that: It also includes a pressure-bearing outer shell, which is a cylindrical structure and is arranged on the outside of the base pipe; the storage device and the driving device are arranged in the pipe segment annulus defined by the inner wall of the pressure-bearing outer shell and the outer wall of the base pipe.

4. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 3 is characterized in that: The storage device includes a storage chamber defined by a portion of the inner wall of the pressure-bearing jacket and a portion of the outer wall of the base tube. The storage chamber is provided with a piston at one end close to the driving device and a discharge joint at the other end; wherein, The piston is an annular structure as a whole, and the inner and outer annular surfaces are respectively slidably sealed with the outer wall of the base tube and the inner wall of the pressure-bearing jacket, and can move axially inside the storage chamber under the driving force of an external force; The agent outlet joint connects and fixes the end of the pressure-bearing jacket to the base pipe and closes the end of the storage chamber; a filling port and an outlet port are provided inside the agent outlet joint, which are respectively used to fill the sealing agent into the storage chamber and discharge the sealing agent from the storage chamber.

5. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 4 is characterized in that: The driving device includes a control circuit, a battery, a driving motor and a plunger pump, wherein: The control circuit is internally provided with a trigger for generating an injection trigger signal at a specified time according to a user setting; or the control circuit is internally provided with a pressure detection device for detecting a pressure wave generated by ground filling and generating an injection trigger signal according to the pressure wave; and the control circuit further controls the operation of the drive motor according to the injection trigger signal; The battery is used to supply power to the control circuit; The driving motor is used to accept the control of the control circuit and drive the plunger pump to operate; The plunger pump is used to be driven by the driving motor to inject the liquid in the wellbore annulus into the closed pressure space on the side of the piston away from the agent outlet joint, drive the piston to move toward the agent outlet joint, and thus discharge the sealing agent in the storage tank through the agent outlet.

6. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 5 is characterized in that: The driving device also includes a liquid inlet joint, which is fixed and sealed to the pipe segment annulus. The liquid inlet joint, the piston, the inner wall of the pressure-bearing jacket, and the outer wall of the base pipe define a closed pressure space. The liquid inlet joint is provided with a plunger pump liquid inlet channel and a plunger pump liquid outlet channel, wherein: The plunger pump liquid inlet channel is connected to the liquid inlet of the plunger pump and the wellbore annulus; The plunger pump liquid outlet channel communicates with the liquid outlet of the plunger pump and the closed pressure space.

7. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 6 is characterized in that: The side of the pipe segment annulus defined by the inner wall of the pressure-bearing outer sleeve and the outer wall of the base pipe away from the storage tank further includes an electric control cabin and an electric cabin, and the axial ends of the electric control cabin and the electric cabin are defined and sealed by the extension fixing portion of the end of the pressure-bearing outer sleeve toward the base pipe and the liquid inlet joint; wherein, The electric control cabin is used to set the control circuit and the battery that supplies power to the control circuit; The electric compartment is used to arrange the driving motor and the plunger pump.

8. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 4 is characterized in that: The driving device includes an elastic force storage device, a limit device, a controller and a releaser, wherein: The controller is provided with a trigger inside, which is used to generate an injection trigger signal at a specified time according to the user setting, and control the releaser to release the limit device according to the injection trigger signal; The releaser is used to accept the control of the controller and release the limiting device; One end of the elastic force storage device is fixed, and the other end is a free end, and the free extension direction of the free end points to the piston; the elastic force storage device is in a compressed state in the initial state, and its extension is limited by the limiting device; when the limiting device is released by the releaser, the free end of the elastic force storage device extends outward and drives the piston to move toward the agent outlet joint, thereby discharging the sealing agent in the storage chamber through the agent outlet.

9. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 8 is characterized in that: The trigger arranged in the controller is an electronic timer or a mechanical timer.

10. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 8, characterized in that: The side of the pipe segment annulus formed by the inner wall of the pressure-bearing outer sleeve and the outer wall of the base pipe away from the storage chamber also includes an elastic drive device cabin, and the axial ends of the elastic drive device cabin are defined and sealed by the extension fixing portion of the end of the pressure-bearing outer sleeve toward the base pipe, and the liquid inlet joint; the elastic force storage device, the limit device, the controller and the releaser are arranged in the elastic drive device cabin.

11. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 8, characterized in that: The elastic force storage device is a spring structure.

12. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 3 is characterized in that: The storage device is a storage bag, which is arranged in a storage chamber defined by part of the inner wall of the pressure-bearing jacket and part of the outer wall of the base tube. The mouth of the storage bag is connected to a discharge joint; the discharge joint connects and fixes the end of the pressure-bearing jacket to the base tube and closes the end of the storage chamber; a discharge port is provided inside the discharge joint for discharging the sealing agent from the storage bag.

13. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 12, characterized in that: The driving device includes a control circuit, a driving motor and a plunger pump, wherein: The control circuit is internally provided with a trigger for generating an injection trigger signal at a specified time according to a user setting; or the control circuit is internally provided with a pressure detection device for detecting a pressure wave generated by ground filling and generating an injection trigger signal according to the pressure wave; and the control circuit further controls the operation of the drive motor according to the injection trigger signal; The driving motor is used to accept the control of the control circuit and drive the plunger pump to operate; The plunger pump is driven by the driving motor to inject the liquid in the wellbore annulus into the agent storage chamber, thereby discharging the sealing agent in the agent storage bag through the agent outlet.

14. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 12, characterized in that: The driving device includes an elastic force storage device, a limit device, a controller and a releaser, wherein: The controller is provided with a trigger inside, which is used to generate an injection trigger signal at a specified time according to the user setting, and control the releaser to release the limit device according to the injection trigger signal; The releaser is used to accept the control of the controller and release the limiting device; One end of the elastic force storage device is fixed, and the other end is a free end, and the free extension direction of the free end points to the storage capsule; the elastic force storage device is in a compressed state in the initial state, and its extension is limited by the limiting device; when the limiting device is released by the releaser, the free end of the elastic force storage device extends toward the storage capsule and squeezes the storage capsule, thereby discharging the sealing agent in the storage capsule through the outlet.

15. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 12, characterized in that: A slider is also provided between the storage bag and the driving device. The slider is an annular structure as a whole, and the inner and outer annular surfaces are respectively slidably fitted with the outer wall of the base tube and the inner wall of the pressure-bearing jacket. Under the drive of the driving device, the slider can move in the axial direction inside the storage chamber, thereby discharging the sealing agent from the storage bag.

16. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 4 or 12, characterized in that: The side of the pipe segment annulus formed by the inner wall of the pressure-bearing sleeve and the outer wall of the base pipe away from the storage chamber also includes an expansion material chamber, and the end of the expansion material chamber axially away from the storage device is defined and sealed by the extension and fixing portion of the end of the pressure-bearing sleeve toward the base pipe, and the storage device is connected; the driving device includes an expansion material arranged in the expansion material chamber; the volume of the expansion material increases after expansion, driving the storage device to inject the sealing agent into the wellbore annulus.

17. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 16, characterized in that: The expansion material is a liquid-expandable material; the driving device also includes a liquid-expandable control valve arranged on the outer wall of the expansion material cabin, and a trigger is provided inside the liquid-expandable control valve, which is used to generate an injection trigger signal at a specified time according to user settings; or, a pressure detection device is provided inside the liquid-expandable control valve, which is used to detect the pressure wave generated by ground filling and generate an injection trigger signal according to the pressure wave; and the liquid-expandable control valve also opens the valve body according to the injection trigger signal to achieve contact between the liquid in the wellbore annulus and the expansion material.

18. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to claim 16, characterized in that: The expansion material is a self-expanding material; the starting expansion time of the self-expanding material is 1-24 hours after the self-driven sealing pipe joint is lowered into the well, and the expansion time of the self-expanding material is 1-48 hours.

19. The self-driving sealing pipe joint for the annulus of the production section of an oil and gas well according to any one of claims 1 to 18, characterized in that: There are two storage devices; the two storage devices share a common outlet, and the outlet is provided with a sealing agent mixing device; and one component sealing agent of a two-component sealing agent is respectively provided in the two storage devices.

20. A method for self-driving and sealing the annulus of a production section of an oil and gas well, using the self-driving and sealing pipe joint for the annulus of a production section of an oil and gas well according to any one of claims 1 to 19, comprising the following steps: (1) Prefabricate a self-driving sealing pipe segment carrying a sealing agent on the central pipe column; wherein, The position of the self-driving sealing pipe segment relative to the central pipe string corresponds to the position of the target sealing point in the wellbore; (2) lowering the central tubular string into the wellbore; (3) the driving device drives the agent storage device to inject the sealing agent into the wellbore annulus according to the injection trigger signal; (4) The sealing agent enters the flow pores of the continuous sealing body in the wellbore annulus and solidifies, forming a sealing body together with the continuous sealing body. The sealing body can prevent the liquid in the wellbore annulus from flowing axially along the wellbore annulus.

21. A completion structure, applied to an oil and gas well in a single formation or penetrating multiple formations, comprising a center string disposed in a production section of the oil and gas well, wherein an annulus is defined between the wellbore wall of the production section and the center string, and a continuous packer formed by accumulation of packing particles is disposed in the annulus; characterized in that: The central pipe string includes the self-driving sealing pipe joint according to any one of claims 1 to 19.

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