Hydraulically-driven self-sealing type hydraulic sand blasting perforator and using method thereof

Abstract

The invention discloses a hydraulic drive self-sealing type hydraulic sand blasting perforator and a using method thereof, and belongs to the field of oil and gas field exploration and development, and the hydraulic drive self-sealing type hydraulic sand blasting perforator comprises a differential pressure drive sliding module and a self-locking-resetting module; the differential pressure driving sliding module comprises an outer wall assembly and an inner gun body. By means of the sliding wear-resistant outer wall driven by differential pressure, the double functions of downward sliding abdicating during perforation and upward sliding self-sealing after pressure relief are achieved in the same tool, direct erosion of a springback sand curtain to a gun body is fundamentally eliminated, and a backflow channel of flowback sand grains is blocked in time. The whole perforation-hole sealing circulation can be completed only by depending on the opening and the reduction of the ground pumping pressure, and any soluble ball is not required to be delivered, pins are not required to be cut off, or subsequent drilling and grinding operation is not required. Continuous and efficient perforation and instant hole sealing operation on multiple layers in one pipe column are achieved, and non-production time and operation cost are greatly reduced.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas field exploration and development, specifically relating to a hydraulically driven self-sealing water jet perforator and its usage method. Background Technology

[0002] Hydraulic jet perforation is a key technology for oil and gas well completion, production enhancement, and deep geothermal development. Its core principle is to utilize high-speed, sand-laden jets to penetrate the casing and formation, creating clean perforation channels to connect the reservoir and the wellbore. With the accelerating global energy structure transformation, the development of enhanced geothermal systems (EGS) is receiving increasing attention. This technology is widely used in fracturing operations in deep, tight geothermal reservoirs, typically at depths exceeding 3000 meters, with temperatures reaching 150-250°C. These reservoirs are characterized by dense rock and low permeability, necessitating the establishment of effective heat exchange channels through hydraulic jet perforation. However, existing technologies generally suffer from the following problems in oil and gas and geothermal applications:

[0003] In traditional single-layer fixed nozzle structures, during perforation, after the high-speed jet impacts the casing and formation, approximately 30-50% of the kinetic energy is reflected back into a "rebound sand curtain" that impacts the outer wall of the nozzle. This causes rapid erosion, thinning, and even delamination around the nozzle and the orifice area. In the high-temperature and high-pressure environment of deep geothermal wells, this erosion failure mode is even more severe—the coupling effect of thermal stress and mechanical erosion accelerates the deterioration of the nozzle material, seriously affecting the nozzle's sealing performance and structural strength, and even leading to premature failure of downhole tools.

[0004] After perforation is completed, sand particles in the flowback fluid can backflow into the annulus of the gun body through the open perforation channel, causing problems such as jamming of the internal sliding sleeve and tearing of sealing elements (such as sealing rings). For geothermal wells, there is often a tendency for high-temperature geothermal fluids and minerals to form scale inside the wellbore. When backflowed sand particles mix with the scale, they are more likely to cause mechanical blockage, increasing the difficulty and cost of well workover operations.

[0005] To address the perforation sealing issue, existing technologies often employ ball-drop opening and closing sliding sleeves (requiring the dropping of soluble balls, shearing pins, and waiting for the balls to dissolve) or a two-run tubing process (perforating first, then running in the sealing tool). These methods are lengthy, rely on multiple stages of operation, and are prone to issues such as incomplete ball placement, ball seat residue, drilling and grinding risks, and additional tripping time and costs. In geothermal development, due to the large well depth and high temperature, the dissolution time of soluble balls is difficult to control, and the tripping costs are significantly higher than in conventional oil and gas wells. Therefore, existing technologies cannot meet the requirements for efficient and continuous operation in a single tubing run, thus hindering the economical and efficient development of deep, tight geothermal reservoirs. Summary of the Invention

[0006] The purpose of this invention is to provide a hydraulically driven self-sealing water jet perforator and its usage method, so as to solve the technical problems in the prior art, such as easy erosion of the gun body, inability to seal the hole immediately after perforation leading to backflow of sand particles, and complex sealing process requiring multiple operations.

[0007] To achieve the above objectives, the present invention provides a hydraulically driven self-sealing water jet perforator, comprising: a differential pressure driven sliding module and a self-locking-reset module;

[0008] The differential pressure driven sliding module includes an outer wall assembly and an inner gun body, wherein the outer wall assembly is slidably sleeved on the inner gun body;

[0009] The internal gun body is provided with at least one jet hole, and the outer wall assembly is provided with a window corresponding to the jet hole;

[0010] An annular cavity is formed between the outer wall assembly and the inner gun body, and the inner gun body is provided with a top drain port communicating with the annular cavity;

[0011] The self-locking-reset module is located at the lower end of the inner gun body and is used to lock the outer wall assembly when it slides to the firing port position and drive it to reset after depressurization.

[0012] The annular cavity forms a hydraulic cylinder. High-pressure fluid enters the annular cavity through the top inlet to drive the outer wall assembly to slide down, aligning the window with the jet orifice for perforation. After depressurization, the self-locking-reset module drives the outer wall assembly to slide up, misaligning the window with the jet orifice to close the channel.

[0013] In one or more embodiments of the present invention, the outer wall assembly includes a sliding sleeve portion and an inner sleeve, the inner sleeve being fixedly sleeved on the outside of the inner gun body, and the sliding sleeve portion being slidably sleeved on the outside of the inner sleeve; the window is opened on the sliding sleeve portion.

[0014] In one or more embodiments of the present invention, the differential pressure driven sliding module further includes an upper end piece, a lower end piece, and a sealing ring; the upper end piece and the lower end piece are fixed to the upper and lower ends of the inner gun body, and together with the inner sleeve and the sliding sleeve portion, they enclose the annular cavity; the sealing ring is disposed on the contact surface between the sliding sleeve portion and the upper end piece, the lower end piece, and the inner sleeve, so as to seal the annular cavity to form a closed piston cavity.

[0015] In one or more embodiments of the present invention, the self-locking-reset module includes:

[0016] A self-locking piston is axially movable within a hydraulic cylinder formed in the lower end member;

[0017] The pressure element, linked to the self-locking piston, can extend or retract radially;

[0018] A buffer spring provides a spring force to the self-locking piston to reset it;

[0019] The bottom inner wall of the sliding sleeve is provided with an annular groove;

[0020] When the sliding sleeve descends to the perforation position, high-pressure fluid enters the hydraulic cylinder through the self-locking drain port, driving the self-locking piston to move and causing the pressure element to extend radially and engage with the annular groove to lock the sliding sleeve.

[0021] In one or more embodiments of the present invention, the self-locking-reset module further includes a lower buffer hydraulic cylinder and a lower buffer hydraulic piston, which cooperate with the self-locking piston to provide hydraulic damping during locking and unlocking.

[0022] In one or more embodiments of the present invention, a diversion device is further included, which is disposed inside the internal gun body, for guiding the high-pressure fluid entering the perforator to the nozzle at the top inlet and the nozzle at the jet orifice in a set ratio.

[0023] In one or more embodiments of the present invention, the sliding sleeve is made of a reinforced alloy material, and its inner wall is provided with a wear-resistant coating or a hardened surface in the area corresponding to the window.

[0024] A method for using the above-described hydraulically driven self-sealing water jet perforator, characterized by comprising the following steps:

[0025] S1: Connect the perforator to the downhole tubing string and lower it to the target well section;

[0026] S2: The ground pump is started and pressurized. The high-pressure fluid enters the annular cavity through the top inlet, pushing the outer wall assembly down to the perforation position and being locked by the self-locking-reset module. At this time, the window is aligned with the jet hole and the water jet perforation operation is carried out.

[0027] S3: After the perforation is completed, the pump is stopped and the pressure is released. The self-locking-reset module is unlocked and drives the outer wall component to slide up and reset, so that the window is misaligned with the jet orifice and the perforation channel is blocked.

[0028] S4: Raise or lower the tubing to the next target position, and repeat steps S2-S3 to achieve multiple perforations and immediate sealing within one trip of the tubing.

[0029] In one or more embodiments of the present invention, in step S2, when the pump pressure rises to the working pressure, the outer wall assembly moves downward at a constant speed under hydraulic drive;

[0030] In step S3, when the pump pressure is released to below a preset threshold, the outer wall assembly automatically moves upward to seal the hole under the reset force driven by the self-locking-reset module.

[0031] In one or more embodiments of the present invention, if sand blockage or abnormal pressure is encountered during perforation operation, an emergency pressure relief operation is performed to rapidly reduce the pump pressure to below 1 MPa, forcing the outer wall assembly to immediately move upward to reset and seal the hole. Subsequently, a large-volume reverse circulation flush is performed to resolve the fault, and the operation can be resumed without removing the tubing.

[0032] Compared with the prior art, the beneficial effect of the present invention is that, through the sliding wear-resistant outer wall driven by pressure difference, the dual functions of sliding down to make way during perforation and sliding up to seal after pressure relief are achieved in the same tool, which fundamentally eliminates the direct erosion of the gun body by the "rebound sand curtain" and immediately blocks the backflow channel of the returned sand particles.

[0033] The entire perforation-sealing cycle can be completed solely by adjusting the pressure of the surface pump, without the need for any soluble balls, shear pins, or subsequent drilling operations. This enables continuous and efficient perforation and immediate sealing operations at multiple layers within a single tubing run, significantly reducing non-productive time and operating costs.

[0034] The self-locking-reset module provides reliable position locking and automatic reset functions, and the buffer design reduces impact. The tool has strong erosion resistance, and can be flexibly adapted to different hole densities and perforation diameters by adjusting the window size and distribution of the sliding sleeve.

[0035] In case of sand blockage or abnormal pressure, the tool can be automatically reset and sealed by emergency pressure relief to ensure downhole safety and allow direct reverse circulation flushing to resolve the fault without the need to pull out the drill string, thus improving the continuity and safety of the operation. Attached Figure Description

[0036] Figure 1 This is a cross-sectional view of a hydraulically driven self-sealing water jetting perforator according to an embodiment of the present invention;

[0037] Figure 2 This is a cross-sectional view of the self-locking-reset module of a hydraulically driven self-sealing water jet perforator in one embodiment of the present invention when it is unlocked;

[0038] Figure 3 This is a cross-sectional view of the self-locking-reset module of a hydraulically driven self-sealing water jet perforator in one embodiment of the present invention during operation.

[0039] Explanation of key figure labels:

[0040] 1. Sliding sleeve; 2. Inner sleeve; 3. Lower end part; 4. Upper end part; 5. Nozzle; 6. Lower buffer pressure cylinder; 7. Lower buffer pressure piston; 8. Diverter; 9. Self-locking module; 10. Buffer spring; 11. Top drain port; 12. Self-locking drain port; 13. Pressure element; 14. Self-locking piston; 15. Sealing ring. Detailed Implementation

[0041] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0042] like Figures 1-3 As shown, this embodiment provides a hydraulically driven self-sealing water jetting perforator, the core of which lies in the linkage design of "differential pressure driving sliding wear-resistant outer wall" and "self-locking-reset".

[0043] The perforator mainly consists of a differential pressure driven sliding module and a self-locking-reset module. The differential pressure driven sliding module is mainly composed of an outer wall assembly, an inner gun body, an upper part 4, a lower part 3, and a sealing ring 15. The self-locking-reset module is integrated inside the lower part 3 and mainly includes a self-locking piston 14, a pressure element 13, a buffer spring 10, a lower buffer pressure cylinder 6, and a lower buffer pressure piston 7. A flow divider 8 and a nozzle 5 are installed on the inner gun body.

[0044] The internal gun body serves as the main pressure-bearing structure of the tool. The inner sleeve 2 is fixed to the outside of the internal gun body via threads or welding, serving as a precision guide for the sliding sleeve 1. The sliding sleeve 1 is fitted over the inner sleeve 2, and precision machining ensures smooth sliding and reliable sealing. The sliding sleeve 1 has windows machined on it, corresponding to the positions of the jet orifices on the internal gun body. The upper end piece 4 and the lower end piece 3 are fixed to the upper and lower ends of the internal gun body, respectively, forming an annular sealed cavity together with the outer wall of the inner sleeve 2 and the inner wall of the sliding sleeve 1. Multiple sealing rings 15 are respectively installed on the mating surfaces of the sliding sleeve 1 with the upper end piece 4, the lower end piece 3, and the inner sleeve 2, ensuring the sealing of the annular cavity and making it an effective hydraulic piston cylinder. The internal gun body contains a flow channel, with its inlet being the top drain port 11, which communicates with the aforementioned annular cavity.

[0045] The self-locking-reset module is installed inside the lower end part 3. The lower end part 3 has a complex cavity machined inside, forming a hydraulic cylinder. The self-locking piston 14 is located within this hydraulic cylinder and can move axially. The pressure element 13 acts as a latch, linked to the self-locking piston 14 via a ramp or linkage mechanism, converting the axial movement of the self-locking piston 14 into the radial extension and retraction of the pressure element 13. A buffer spring 10 acts on the self-locking piston 14, providing it with an upward reset force. The lower buffer hydraulic cylinder 6 and the lower buffer hydraulic piston 7 form a damping hydraulic cylinder, associated with the movement of the self-locking piston 14, used to absorb the impact during locking and unlocking, ensuring smooth operation. A ring groove is machined on the lower inner wall of the sliding sleeve part 1. A self-locking drain port 12 is opened on the lower end part 3 to introduce high-pressure fluid from inside the tool into the hydraulic cylinder of the self-locking-reset module.

[0046] The diversion device 8 is fixed inside the internal flow channel of the gun body, located downstream of the top inlet 11. Its internal design incorporates a specific throttling or distribution structure, capable of distributing the high-pressure working fluid pumped from the wellhead according to a pre-set flow rate ratio. A portion of the fluid is guided through the diversion device 8 to the top inlet 11 to drive the differential pressure drive sliding module; the other portion continues to flow downwards, exiting through the nozzle 5 to form a high-speed jet for perforation. This design ensures that the driving hydraulic pressure and the jet power are from the same source and their proportions are controllable.

[0047] The sliding sleeve 1 is made of a high-strength, high-wear-resistant reinforced alloy. On its inner side, especially in the area around the corresponding window, a hard alloy layer can be further overlaid, or surface hardening treatments such as nitriding and chromium plating can be performed to form a wear-resistant coating or hardened surface, which greatly enhances its ability to resist the erosion of the rebound sand curtain.

[0048] Combination Figures 1-3 As shown, the working process of the hydraulically driven self-sealing water jet perforator is as follows:

[0049] Initial / Sealing State: During tool downhole operation or after pump shutdown and depressurization, the sliding sleeve 1 is in its upper limit position, i.e., the sealing position, under the reset force of the self-locking-reset module. At this time, the window on the sliding sleeve 1 is completely misaligned with the jet orifice and nozzle 5 on the internal gun body, and the solid part of the sliding sleeve 1 completely covers the orifice, forming a mechanical seal. The sealing ring 15 ensures the sealing performance.

[0050] Perforation status: After the tool reaches the predetermined perforation position, the ground pump is activated to pressurize the fluid. The high-pressure working fluid flows through the internal channels of the tool to the diversion device 8. After diversion, a portion of the high-pressure fluid enters the annular cavity formed by the sliding sleeve 1, inner sleeve 2, upper end piece 4, and lower end piece 3 through the top inlet 11. The pressure inside the cavity increases, pushing the sliding sleeve 1 to slide downwards against friction and spring preload.

[0051] When the sliding sleeve 1 descends to a specific position, namely the perforation position, its internal annular groove moves precisely to the radial position corresponding to the pressure element 13. Simultaneously, high-pressure fluid enters the hydraulic cylinder below the self-locking piston 14 through the self-locking inlet 12, pushing the self-locking piston 14 upward. The self-locking piston 14, through a linkage mechanism, drives the pressure element 13 to extend radially outward, precisely engaging it in the annular groove at the bottom of the sliding sleeve 1, achieving rigid mechanical locking and preventing displacement of the sliding sleeve due to vibration or pressure fluctuations during perforation operations.

[0052] At this point, the window on the sliding sleeve 1 is perfectly aligned with the jet orifice and nozzle 5 of the internal gun body, and the jet channel is fully open. The main working fluid distributed from the diversion device 8 is ejected at high speed through the nozzle 5, impacting the casing and the formation to complete the hydraulic sandblasting perforation operation. During this process, the rebounding sand particles directly impact the reinforced inner wall of the sliding sleeve 1, protecting the internal gun body.

[0053] Reset to sealed state: After the perforation operation at this point is completed, the ground pump is stopped and pressure is released. As the internal pressure of the tool decreases, the hydraulic pressure acting on the back of the self-locking piston 14 rapidly decreases. The potential energy stored in the buffer spring 10 is released, pushing the self-locking piston 14 to move in the opposite direction, causing the pressure element 13 to retract radially from the annular groove, releasing the lock on the sliding sleeve 1. At the same time, due to the decrease in pressure within the annular cavity, the sliding sleeve 1 slides upward under the drive of the reset force until it returns to the initial sealing position. The window and the orifice are misaligned again, and the sliding sleeve 1 re-seals the perforation channel, effectively preventing the backflow of sand particles in the subsequent backflow fluid.

[0054] Continuous operation: After completing the operation at this target point, the perforator can be moved to the next target location by raising or lowering the tubing string. By repeating the above "pressurization-perforation-depressurization-sealing" process, multi-stage and multi-segment perforation and immediate sealing operations can be achieved within a single tubing string run.

[0055] It is worth noting that during perforation or fracturing, if sand blockage causes an abnormal increase in pressure or other emergencies, an emergency depressurization operation can be immediately performed to quickly reduce the wellhead pump pressure to below 1 MPa. At this time, regardless of the state of the sliding sleeve, the self-locking-reset module will quickly activate due to the disappearance of back pressure, driving the sliding sleeve section 1 to immediately move upwards and reset, forcibly closing the perforation channel. After sealing, a large-volume reverse circulation flush can be performed from the annulus to flush out sand bridges or sediments in the wellbore, resolving the fault. After the fault is cleared, pressure can be directly restored, and subsequent operations can continue without having to pull out the tubing to change tools, greatly improving the safety and continuity of the operation.

[0056] Example 2

[0057] This embodiment is basically the same as Embodiment 1, with the main difference being the window design of the sliding sleeve 1. To adapt to different formation conditions and production increase requirements, the windows on the sliding sleeve 1 can be designed in multiple sets, distributed along the axial direction with different densities and phase angles. The arrangement of the jet orifices and nozzles 5 on the internal gun body corresponds accordingly. Through this design, the same specification of perforator can adapt to various perforation schemes by replacing the sliding sleeve 1 with different window patterns, enhancing the tool's versatility and flexibility.

[0058] Example 3

[0059] This embodiment is basically the same as Embodiment 1, except for the driving method of the self-locking-reset module. Besides directly driving the self-locking piston 14 hydraulically, a differential pressure-sensitive diaphragm or small piston mechanism can be installed between the self-locking piston 14 and the pressure element 13. When the sliding sleeve 1 moves into position, the high pressure in the annular cavity acts on this mechanism through a small hole, generating an amplified force to push the pressure element 13 to lock, making the locking action more sensitive and reliable in response to pressure changes.

[0060] This invention achieves the dual functions of sliding and self-sealing during perforation and sliding upward after depressurization within the same tool through a pressure differential driven sliding wear-resistant outer wall. This fundamentally eliminates the direct erosion of the gun body by the "rebound sand curtain" and immediately blocks the backflow channel of the returned sand particles.

[0061] The entire perforation-sealing cycle can be completed solely by adjusting the pressure of the surface pump, without the need for any soluble balls, shear pins, or subsequent drilling operations. This enables continuous and efficient perforation and immediate sealing operations at multiple layers within a single tubing run, significantly reducing non-productive time and operating costs.

[0062] The self-locking-reset module provides reliable position locking and automatic reset functions, and the buffer design reduces impact. The tool has strong erosion resistance, and can be flexibly adapted to different hole densities and perforation diameters by adjusting the window size and distribution of the sliding sleeve.

[0063] In case of sand blockage or abnormal pressure, the tool can be automatically reset and sealed by emergency pressure relief to ensure downhole safety and allow direct reverse circulation flushing to resolve the fault without the need to pull out the drill string, thus improving the continuity and safety of the operation.

[0064] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0065] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A hydraulically driven self-sealing water jet perforator, characterized in that, include: Differential pressure driven sliding module and self-locking-reset module; The differential pressure driven sliding module includes an outer wall assembly and an inner gun body, wherein the outer wall assembly is slidably sleeved on the inner gun body; The internal gun body is provided with at least one jet hole, and the outer wall assembly is provided with a window corresponding to the jet hole; An annular cavity is formed between the outer wall assembly and the inner gun body, and the inner gun body is provided with a top drain port communicating with the annular cavity; The self-locking-reset module is located at the lower end of the inner gun body and is used to lock the outer wall assembly when it slides to the firing port position and drive it to reset after depressurization. The annular cavity forms a hydraulic cylinder. High-pressure fluid enters the annular cavity through the top inlet to drive the outer wall assembly to slide down, aligning the window with the jet orifice for perforation. After depressurization, the self-locking-reset module drives the outer wall assembly to slide up, misaligning the window with the jet orifice to close the channel.

2. The hydraulically driven self-sealing water jet perforator according to claim 1, characterized in that, The outer wall assembly includes a sliding sleeve and an inner sleeve. The inner sleeve is fixedly fitted onto the outside of the inner gun body, and the sliding sleeve is slidably fitted onto the outside of the inner sleeve. The window is opened on the sliding sleeve.

3. The hydraulically driven self-sealing water jet perforator according to claim 2, characterized in that, The differential pressure driven sliding module also includes an upper end piece, a lower end piece, and a sealing ring; the upper end piece and the lower end piece are fixed to the upper and lower ends of the inner gun body, and together with the inner sleeve and the sliding sleeve, they form the annular cavity; the sealing ring is disposed on the contact surface between the sliding sleeve and the upper end piece, the lower end piece, and the inner sleeve, so as to seal the annular cavity to form a closed piston cavity.

4. The hydraulically driven self-sealing water jet perforator according to claim 3, characterized in that, The self-locking-reset module includes: A self-locking piston is axially movable within a hydraulic cylinder formed in the lower end member; The pressure element, linked to the self-locking piston, can extend or retract radially; A buffer spring provides a spring force to the self-locking piston to reset it; The bottom inner wall of the sliding sleeve is provided with an annular groove; When the sliding sleeve descends to the perforation position, high-pressure fluid enters the hydraulic cylinder through the self-locking drain port, driving the self-locking piston to move and causing the pressure element to extend radially and engage with the annular groove to lock the sliding sleeve.

5. The hydraulically driven self-sealing water jet perforator according to claim 4, characterized in that, The self-locking-reset module also includes a lower buffer hydraulic cylinder and a lower buffer hydraulic piston, which cooperate with the self-locking piston to provide hydraulic damping during locking and unlocking.

6. The hydraulically driven self-sealing water jet perforator according to claim 1, characterized in that, It also includes a diversion device, which is located inside the internal gun body, for directing the high-pressure fluid entering the perforator to the nozzle at the top inlet and the nozzle at the jet orifice in a set ratio.

7. The hydraulically driven self-sealing water blasting perforator according to claim 6, characterized in that, The sliding sleeve is made of reinforced alloy material, and its inner wall is provided with a wear-resistant coating or a hardened surface in the area corresponding to the window.

8. A method for using a hydraulically driven self-sealing water jet perforator as described in any one of claims 1-7, characterized in that, Includes the following steps: S1: Connect the perforator to the downhole tubing string and lower it to the target well section; S2: The ground pump is started and pressurized. The high-pressure fluid enters the annular cavity through the top inlet, pushing the outer wall assembly down to the perforation position and being locked by the self-locking-reset module. At this time, the window is aligned with the jet hole and the water jet perforation operation is carried out. S3: After the perforation is completed, the pump is stopped and the pressure is released. The self-locking-reset module is unlocked and drives the outer wall component to slide up and reset, so that the window is misaligned with the jet orifice and the perforation channel is blocked. S4: Raise or lower the tubing to the next target position, and repeat steps S2-S3 to achieve multiple perforations and immediate sealing within one trip of the tubing.

9. The method according to claim 8, characterized in that, In step S2, when the pump pressure rises to the working pressure, the outer wall assembly descends at a constant speed under hydraulic drive; In step S3, when the pump pressure is released to below a preset threshold, the outer wall assembly automatically moves upward to seal the hole under the reset force driven by the self-locking-reset module.

10. The method according to claim 8 or 9, characterized in that, If sand blockage or abnormal pressure occurs during perforation, an emergency pressure relief operation is performed to rapidly reduce the pump pressure to below 1 MPa, forcing the outer wall assembly to immediately move upward to reset and seal the hole. Subsequently, a large-volume reverse circulation flush is performed to resolve the fault, and the operation can be resumed without removing the tubing.

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