Electric heating pulse plug removal tool, implementation process and special piston mechanism

Abstract

The invention discloses an electric heating pulse unblocking tool, an implementation process and a special piston mechanism. The electric heating pulse unblocking tool comprises a pulse generating device, the device further comprises upstream and downstream movable unhooking type piston mechanisms. The pulse generating device is provided with a first acting end and a second acting end; the upper end and the lower end of the upstream and downstream movable unhooking type piston mechanism are connected with the first acting end and the second acting end of the pulse generating device respectively. The device is small in occupied area, simple in structure, convenient and safe to use, large in pulse pressure, easy to control and free of pollution, the maximum pressure can be borne by the barbs, the device can adapt to different reservoir conditions, the unblocking efficiency is improved through repeated pulses, and the unblocking capacity is also improved through high-temperature gas.

Description

Technical Field

[0001] The invention relates to the technical field of oil extraction, in particular to an electric heat pulse plugging removal tool and an implementation process and a special piston mechanism. Background Art

[0002] In the later stage of oil and gas field development, it is usually necessary to treat the produced fluid and then inject it back into the formation to replenish energy. If the produced fluid is not treated cleanly during this process, it will bring substances such as chloride ions, scale and iron particles, which will block the oil layer channels and affect the development of the well network. If acid fracturing is carried out, it will not only increase the cost but also pollute the oil and gas reservoirs and even affect other layers. The formation belongs to a balanced pressure system where gas, liquid and solid coexist. The main rock framework damage includes solid particles, chemical precipitation, fluid and Jamin effect damage.

[0003] In addition, problems such as particle movement blocking pore throats during mining and excessive injection water inducing chemical crystallization will block the formation. Currently, multiple technologies such as frequency method, acoustic wave method and pressure pulse method are used for unblocking. Physical and chemical comprehensive unblocking methods are also adopted in some blocks, which have achieved remarkable results, but the cost is also high. The more common ones are acid unblocking, positive water hammer-chemical unblocking, etc.

[0004] Pulse unblocking technology is a technical solution that uses pressure waves to improve the performance of near-wellbore formations. This technical solution mainly uses multiple pressure pulse shocks to remove blockages of rock debris, drilling fluid, artificial filling particles and other materials in the near-wellbore formation, destroy salt deposits, increase the seepage capacity of the near-wellbore formation, and improve the flow performance of the produced fluid, thereby achieving the purpose of increasing the production of oil and gas wells.

[0005] Publication (announcement) number: CN207437047U, Publication (announcement) date: 2018-06-01 A high-power pulse generator for oil fields is disclosed, including a power control cabinet, which is connected to a DC high-voltage power supply, an energy storage capacitor, an energy controller and an energy converter in sequence through cables. An energetic mixture component is arranged inside the energy converter, which solves the problem of low pulse power in the prior art oscillation unblocking technology. The high-power pulse generator can induce the energetic mixture in the energetic mixture component to release chemical energy, form an electrothermal pulse, and increase the pulse energy. It not only has a fracturing effect, forms new cracks in the reservoir, and increases the permeability of the formation, but also has an unblocking effect and promotes seepage.

[0006] The above technologies cannot achieve the selection and adjustment of each pulse pressure value, cannot adapt to different reservoir conditions, and cannot achieve the purpose of heating, steam injection, and multiple repeated pulses.

[0007] Publication (announcement) number: CN214062895U, Publication (announcement) date: 2021-08-27 It involves a water injection and unblocking technology field for oil production acidizing construction, and specifically involves a hydraulic pulse oscillation unblocking tool for acidizing construction. It includes an upper joint, a mushroom head, an adjustment pad, a liquid distribution seat, a push rod, a cylinder sleeve, a diversion regulating nozzle, a piston upper body, a pulse nozzle, a piston lower body, a spring, a lower joint, a diversion nozzle and a plug. It has a simple structure and reliable functions, simplifies downhole operations, improves operating efficiency, greatly saves costs, and combines high-pressure cavitation jets, hydraulic oscillations and hydraulic pulse unblocking technologies, thereby shortening the acidizing time.

[0008] The above technologies cannot achieve the selection and adjustment of each pulse pressure value, cannot adapt to different reservoir conditions, and cannot achieve the purpose of heating, steam injection, and multiple repeated pulses.

[0009] Publication (announcement) number: CN101033684B, Publication (announcement) date: 2010-05-19 Disclosed is a mechanical unblocking oil production device capable of increasing the mechanical oil production of petroleum wells, which is composed of an upper joint, a forward check valve, an upper center pipe, a variable diameter piston assembly, a lower joint, a lower center pipe, a hollow vibration ring assembly, a vibration plate group, an outer cylinder, a reverse check valve and a screen pipe, wherein the variable diameter piston assembly is mounted on the middle part of the upper center pipe, the hollow vibration ring assembly is mounted on the upper part of the lower center pipe, and the vibration plate group is installed in the middle part of the lower center pipe. The present invention is installed in the casing and connected to the oil pipe at the bottom of the oil pump. When the oil pump is in the upstroke, the mechanical unblocking oil extractor moves upward with the elastic contraction of the oil pipe, hits the hollow vibration ring assembly, generates vibration waves, and at the same time, forms a negative pressure area in the area below the forward check valve, generating a negative pressure hydraulic wave; when the oil pump is in the downstroke, the mechanical unblocking oil extractor moves downward with the elastic extension of the oil pipe, hits the hollow vibration ring assembly, generates vibration waves, and at the same time, forms a high pressure area in the area below the reverse check valve, generating a high pressure hydraulic wave. The mechanical unblocking oil extractor utilizes the periodic elastic deformation of the oil pipe column to achieve periodic pulse reciprocating motion, converts the impact energy and liquid pressure change energy inside the system into wave energy, transmits it into the oil flow channel in the formation, removes the blockage of the oil layer, and thus achieves the purpose of increasing crude oil production.

[0010] The above technologies cannot achieve the selection and adjustment of each pulse pressure value, cannot adapt to different reservoir conditions, and cannot achieve the purpose of heating, steam injection, and multiple repeated pulses.

[0011] In summary, the technical solutions of the above-disclosed technologies, the technical problems to be solved, and the beneficial effects produced are all different from the present invention. Regarding more technical features, technical problems to be solved, and beneficial effects of the present invention, the above-disclosed technical documents do not provide any technical inspiration. Summary of the invention

[0012] In view of the above-mentioned defects of the prior art, the purpose of the present invention is to provide an electrothermal pulse unblocking tool and an implementation process and a special piston mechanism, combining the advantages of the prior art and optimizing and integrating them, so as to more efficiently, conveniently and quickly unblock the near-wellbore formation, and designing a gas injection-heating integrated repeated pulse unblocking device. One device can realize heating, steam injection, and multiple repeated pulses, thereby reducing some costs and labor costs and being easy to operate.

[0013] In order to achieve the above object, the present invention adopts the following technical solutions:

[0014] An electrothermal pulse plugging removal tool comprises a pulse generating device;

[0015] It also includes an up-and-down moving unhooking piston mechanism;

[0016] The pulse generating device has a first action end and a second action end; the upper and lower ends of the up-and-downward movable decoupling piston mechanism are respectively connected to the first action end and the second action end of the pulse generating device.

[0017] The up-and-down moving unhooking piston mechanism comprises a piston cylinder, a shuttle piston, and a rubber protective sealing sleeve;

[0018] A rubber protective sealing sleeve is arranged on the inner wall of the piston cylinder, a sealing sleeve through hole is arranged in the middle of the rubber protective sealing sleeve, a gas injection hole is arranged in the middle of the piston cylinder, and the sealing sleeve through hole is correspondingly connected with the gas injection hole of the piston cylinder;

[0019] The outer wall of the shuttle-shaped piston can perform an upward and downward movable intermittent seal with the inner wall of the rubber protective sealing sleeve.

[0020] The inner wall of the rubber protective sealing sleeve is provided with an upper inner conical surface and a lower inner conical surface, and the outer wall of the shuttle-shaped piston is provided with an upper outer conical surface and a lower outer conical surface, wherein the upper outer conical surface can fit tightly against the upper inner conical surface, and the lower outer conical surface can fit tightly against the lower inner conical surface.

[0021] The inner wall of the piston cylinder is provided with an upper barb obliquely upward and a lower barb obliquely downward;

[0022] The upper outer conical surface of the shuttle piston is provided with an upper depression, and the lower outer conical surface is provided with a lower depression. When the shuttle piston moves upward, the upper barb can be inserted into the upper depression, and when the shuttle piston moves downward, the lower barb can be inserted into the lower depression.

[0023] The piston cylinder is a cylindrical container.

[0024] The first action end of the pulse generating device includes a first gas injection pipe and a first heating metal rod, and the second action end includes a second gas injection pipe and a second heating metal rod;

[0025] The first action end extends into the upper end cavity of the piston cylinder, corresponding to the upper space of the shuttle piston, and the second action end extends into the lower end cavity of the piston cylinder, corresponding to the lower space of the shuttle piston.

[0026] The upper end of the piston cylinder is connected to a faucet, and the upper end of the faucet is connected to a lifting system.

[0027] The pulse generating device is connected to a ground energy supply system.

[0028] The ground energy supply system includes a high-pressure gas supply system and an electric power supply system. The power supply system can freely adjust the voltage to make the heating efficiency higher; the power supply is connected to the electric heating metal rod through a cable, and the gas supply device injects gas into the cylindrical cavity through a high-temperature and high-pressure pipeline.

[0029] In order to achieve the above object, the present invention adopts the following technical solutions:

[0030] An implementation process of an electrothermal pulse plugging removal tool comprises the following steps:

[0031] The first step is to lower the plugging removal device into the wellbore through the lifting system so that the gas injection hole corresponds to the wellbore perforation;

[0032] The second step is to turn on the power supply of the upper heating metal rod and inject gas into the space above the shuttle piston to reach the required pressure. The piston is unhooked from the upper barb and slides to the lower part of the cavity. The gas is ejected through the gas injection port and enters the formation. A pulse action is completed.

[0033] The third step is to open the heating metal rod and the steam injection port in the space below the piston after one pulse, push the piston upward, and make the lower barb hook the piston, so that the pressure and temperature in the closed space continue to rise. When the unhooking pressure is reached, the piston is pushed upward, and the gas is ejected from the gas injection hole again;

[0034] The fourth step is to repeat the above steps to continuously deblock the near-wellbore formation for multiple times.

[0035] Before the first step, preparatory steps are performed to connect the ground power supply system and the gas supply system through cables and pipelines, and to check the sealing of the connection of the electric thermal pulse deblocking tool.

[0036] In order to achieve the above object, the present invention adopts the following technical solutions:

[0037] A special up-and-down moving unhooking piston mechanism for an electrothermal pulse plugging removal tool, comprising a piston cylinder, a shuttle piston, and a rubber protective sealing sleeve;

[0038] A rubber protective sealing sleeve is arranged on the inner wall of the piston cylinder, a sealing sleeve through hole is arranged in the middle of the rubber protective sealing sleeve, a gas injection hole is arranged in the middle of the piston cylinder, and the sealing sleeve through hole is correspondingly connected with the gas injection hole of the piston cylinder;

[0039] The outer wall of the shuttle-shaped piston can perform an upward and downward movable intermittent seal with the inner wall of the rubber protective sealing sleeve.

[0040] The inner wall of the rubber protective sealing sleeve is provided with an upper inner conical surface and a lower inner conical surface, and the outer wall of the shuttle-shaped piston is provided with an upper outer conical surface and a lower outer conical surface, wherein the upper outer conical surface can fit tightly against the upper inner conical surface, and the lower outer conical surface can fit tightly against the lower inner conical surface.

[0041] The inner wall of the piston cylinder is provided with an upper barb obliquely upward and a lower barb obliquely downward;

[0042] The upper outer conical surface of the shuttle piston is provided with an upper depression, and the lower outer conical surface is provided with a lower depression. When the shuttle piston moves upward, the upper barb can be inserted into the upper depression, and when the shuttle piston moves downward, the lower barb can be inserted into the lower depression.

[0043] The piston cylinder is a cylindrical container.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] 1. The present invention has a small footprint, a simple structure, is easy and safe to use, and has a large pulse pressure, is easy to control, and is pollution-free. The barb can be adjusted to withstand the maximum pressure and can adapt to different reservoir conditions. Repeated pulses improve the unblocking efficiency, and high-temperature gas also improves the unblocking ability.

[0046] 2. The present invention generates high-pressure and high-temperature pulse gas, converting continuous impact unblocking into pulse unblocking, which not only saves costs but also improves unblocking efficiency. At the same time, the sweep coefficient can be promoted because the pulse can be repeated many times. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a structural schematic diagram of an electrothermal pulse plugging removal tool according to an embodiment of the present invention;

[0048] Figure 2 It is a top view of the shuttle piston;

[0049] Figure 3 It is a partial enlarged view of the upstream and downstream uncoupling piston mechanism.

[0050] Among them: 1. Ground energy supply system; 2. Lifting system; 3. Horsehead; 4. Gas injection pipe; 5. Heating metal rod; 6. Gas injection hole; 7. Wellbore perforation; 8. Shuttle piston; 9. Barb; 10. Cylindrical container; 11. Casing; 12. Thickened rubber protective sealing sleeve. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] Reference Figures 1 to 3 , an electrothermal pulse plugging removal tool, comprising a pulse generating device;

[0053] It also includes an up-and-down moving unhooking piston mechanism;

[0054] The pulse generating device has a first action end and a second action end; the upper and lower ends of the up-and-downward movable decoupling piston mechanism are respectively connected to the first action end and the second action end of the pulse generating device.

[0055] The up-and-down moving unhooking piston mechanism comprises a piston cylinder, a shuttle piston, and a rubber protective sealing sleeve;

[0056] A rubber protective sealing sleeve is arranged on the inner wall of the piston cylinder, a sealing sleeve through hole is arranged in the middle of the rubber protective sealing sleeve, a gas injection hole is arranged in the middle of the piston cylinder, and the sealing sleeve through hole is correspondingly connected with the gas injection hole of the piston cylinder;

[0057] The outer wall of the shuttle-shaped piston can perform an upward and downward movable intermittent seal with the inner wall of the rubber protective sealing sleeve.

[0058] The inner wall of the rubber protective sealing sleeve is provided with an upper inner conical surface and a lower inner conical surface, and the outer wall of the shuttle-shaped piston is provided with an upper outer conical surface and a lower outer conical surface, wherein the upper outer conical surface can fit tightly against the upper inner conical surface, and the lower outer conical surface can fit tightly against the lower inner conical surface.

[0059] The inner wall of the piston cylinder is provided with an upper barb obliquely upward and a lower barb obliquely downward;

[0060] The upper outer conical surface of the shuttle piston is provided with an upper depression, and the lower outer conical surface is provided with a lower depression. When the shuttle piston moves upward, the upper barb can be inserted into the upper depression, and when the shuttle piston moves downward, the lower barb can be inserted into the lower depression.

[0061] The piston cylinder is a cylindrical container.

[0062] The first action end of the pulse generating device includes a first gas injection pipe and a first heating metal rod, and the second action end includes a second gas injection pipe and a second heating metal rod;

[0063] The first action end extends into the upper end cavity of the piston cylinder, corresponding to the upper space of the shuttle piston, and the second action end extends into the lower end cavity of the piston cylinder, corresponding to the lower space of the shuttle piston.

[0064] The upper end of the piston cylinder is connected to a faucet, and the upper end of the faucet is connected to a lifting system.

[0065] The pulse generating device is connected to a ground energy supply system.

[0066] Embodiment 1:

[0067] Reference Figures 1 to 3 , an embodiment provided by the present invention:

[0068] An electrothermal pulse unblocking tool comprises a ground energy supply system 1, a lifting system 2, a faucet 3, a sleeve 11, a shuttle plunger 8, a barb 9, and a cylindrical container 10.

[0069] The ground energy supply system 1, the lifting system 2, the faucet 3, and the casing 11 all belong to the existing technology and can be directly applied.

[0070] A lifting system 2 and an energy supply system 1 are arranged on the ground. The lifting system is connected to a faucet 3. Ground cables and pipelines are connected to a designed cylindrical container 10 through a faucet. A heating metal rod 5 and an air injection pipeline 4 are connected to the upper and lower ends of the cylindrical container. A shuttle-shaped piston 8 is arranged in the middle of the cylindrical container. Barbs 9 and thickened rubber 12 are arranged on the wall of the cylindrical container.

[0071] The cylindrical container 10 is a cylinder with a cavity inside. There are four barbs on the inner wall of the cylindrical cavity, a thickened high-temperature resistant rubber protective layer on the wall, and a heating metal rod and an air injection port are provided on the top and bottom of the cylindrical cavity.

[0072] The high temperature resistant rubber on the wall of the cylindrical container 10 can prevent the internal piston from colliding with the cavity wall and the electrically heated metal rod when moving at high speed, and improve the sealing performance of the gas injection process by thickening the high temperature resistant rubber protective sealing sleeve.

[0073] There are depressions on both sides of the piston to facilitate hooking of the barb so as to increase the maximum gas injection pressure in the cavity and remove the blockage more effectively. The piston is made of elastic material or the barb is made of elastic material, or both are made of elastic material, and through elasticity, they can be unhooked from each other under a certain pressure.

[0074] The lifting system is a winch, which is connected to the lower hoe in the well.

[0075] The ground energy supply system includes a high-pressure gas supply system and a power supply system. The power supply system can freely adjust the voltage to make the heating efficiency higher. The power supply is connected to the electric heating metal rod through a cable, and the gas supply device injects gas into the cylindrical cavity through a high-temperature and high-pressure pipeline.

[0076] The barb is on the cylinder wall and can hook the piston during the gas injection process. When the set pressure is reached, the piston breaks through and the gas is released. When the piston passes from the back, it can make a smaller pass, so that it can hook the piston again on the other side, and multiple repeated pulses can be achieved.

[0077] The piston can fit tightly with the rubber protective sleeve to maintain sealing.

[0078] Gas injection pipeline, high temperature and high pressure resistant steel wire hose.

[0079] This embodiment is applied to the oil layer section with a well depth of 1500m, a reservoir pressure of 18MPa, and a fracture pressure of 30Mpa. The structural dimensions are designed as follows:

[0080] The length of the oil pipe is 20m, the outer diameter of the oil pipe is 114.3mm, the wall thickness is 6.35mm, and the inner diameter is 101.6mm;

[0081] The cylindrical container has an outer diameter of 100 mm and a wall thickness of 10 mm;

[0082] The diameter of the cylindrical cavity is 80 mm;

[0083] The maximum diameter of the plunger is 50mm and the minimum diameter is 20mm.

[0084] The method of using the above-mentioned electric pulse plugging removal tool is as follows:

[0085] (1) Connect the ground power supply system and gas supply system through cables and pipelines, and check the tightness of the device connections;

[0086] (2) lowering the plugging removal device into the wellbore through the lifting system so that the gas outlet corresponds to the wellbore perforation;

[0087] (3) Turn on the power supply of the upper heating metal rod and inject gas into the space above the piston to reach the required pressure. The piston is unhooked and slides to the lower part of the cavity. The gas is ejected through the injection port and enters the formation.

[0088] (4) After one pulse, the heating metal rod and the steam injection port in the space below the piston are opened, and the piston is pushed upward, so that the barb hooks the piston, and the pressure and temperature in the enclosed space continue to rise. When the unhooking pressure is reached, the piston is pushed upward, and the gas is ejected from the injection hole again;

[0089] (5) Repeat steps (2) to (4) to continue to repeatedly unblock the near-wellbore formation.

[0090] This embodiment innovates the electrothermal pulse unblocking tool and method of use, improves operational safety and construction success rate, can greatly save construction time and cost, and further demonstrates the advantages of high-pressure and high-temperature gas pulse unblocking. Under the same well conditions, this embodiment is better than traditional unblocking tools, with simpler control and higher safety. The electrothermal pulse unblocking technology of this embodiment overcomes the unfavorable factors that restrict its application, and its advantages are more obvious in unconventional oil and gas field reservoir transformation and production increase measures.

[0091] Embodiment 2:

[0092] An electrothermal pulse unblocking tool has a structure as described in Example 1, except that the maximum pressure limit set for the barb 9 is different and the wall thickness of the closed cavity is different. By increasing the pulse pressure, the unblocking effect is improved.

[0093] This embodiment is applied to the oil layer section with a well depth of 4700m, a reservoir pressure of 50MPa, and a fracture pressure of 90Mpa. The structural dimensions are designed as follows:

[0094] The outer diameter of the casing is 127.9mm, the wall thickness is 6.43mm, and the inner diameter is 114.14mm;

[0095] The cylindrical container has an outer diameter of 112 mm, a wall thickness of 16 mm, and an inner diameter of 80 mm;

[0096] The maximum diameter of the plunger is 50mm and the minimum diameter is 20mm.

[0097] Embodiment 3:

[0098] A special up-and-down moving unhooking piston mechanism for an electrothermal pulse plugging removal tool, comprising a piston cylinder, a shuttle piston, and a rubber protective sealing sleeve;

[0099] A rubber protective sealing sleeve is arranged on the inner wall of the piston cylinder, a sealing sleeve through hole is arranged in the middle of the rubber protective sealing sleeve, a gas injection hole is arranged in the middle of the piston cylinder, and the sealing sleeve through hole is correspondingly connected with the gas injection hole of the piston cylinder;

[0100] The outer wall of the shuttle-shaped piston can perform an upward and downward movable intermittent seal with the inner wall of the rubber protective sealing sleeve.

[0101] The inner wall of the rubber protective sealing sleeve is provided with an upper inner conical surface and a lower inner conical surface, and the outer wall of the shuttle-shaped piston is provided with an upper outer conical surface and a lower outer conical surface, wherein the upper outer conical surface can fit tightly against the upper inner conical surface, and the lower outer conical surface can fit tightly against the lower inner conical surface.

[0102] The inner wall of the piston cylinder is provided with an upper barb obliquely upward and a lower barb obliquely downward;

[0103] The upper outer conical surface of the shuttle piston is provided with an upper depression, and the lower outer conical surface is provided with a lower depression. When the shuttle piston moves upward, the upper barb can be inserted into the upper depression, and when the shuttle piston moves downward, the lower barb can be inserted into the lower depression.

[0104] The piston cylinder is a cylindrical container.

[0105] All components and connection methods of components not discussed in this application belong to the known technologies in this technical field and can be directly applied without further explanation.

[0106] In the present invention, the term "plurality" refers to two or more than two, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0107] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “front” and “back” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, cannot be understood as a limitation on the present invention.

[0108] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0109] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An electrothermal pulse plugging removal tool, comprising a pulse generating device; It is characterized in that It also includes an up-and-down moving unhooking piston mechanism; The pulse generating device has a first action end and a second action end; the upper and lower ends of the up-and-downward movable decoupling piston mechanism are respectively connected to the first action end and the second action end of the pulse generating device.

2. The electrothermal pulse plugging removal tool according to claim 1, characterized in that: The up-and-down moving unhooking piston mechanism comprises a piston cylinder, a shuttle piston, and a rubber protective sealing sleeve; A rubber protective sealing sleeve is arranged on the inner wall of the piston cylinder, a sealing sleeve through hole is arranged in the middle of the rubber protective sealing sleeve, a gas injection hole is arranged in the middle of the piston cylinder, and the sealing sleeve through hole is correspondingly connected with the gas injection hole of the piston cylinder; The outer wall of the shuttle-shaped piston can perform an upward and downward movable intermittent seal with the inner wall of the rubber protective sealing sleeve.

3. The electrothermal pulse plugging removal tool according to claim 2, characterized in that: The inner wall of the rubber protective sealing sleeve is provided with an upper inner conical surface and a lower inner conical surface, and the outer wall of the shuttle-shaped piston is provided with an upper outer conical surface and a lower outer conical surface, wherein the upper outer conical surface can fit tightly against the upper inner conical surface, and the lower outer conical surface can fit tightly against the lower inner conical surface.

4. The electrothermal pulse plugging removal tool according to claim 3, characterized in that: The inner wall of the piston cylinder is provided with an upper barb obliquely upward and a lower barb obliquely downward; The upper outer conical surface of the shuttle piston is provided with an upper depression, and the lower outer conical surface is provided with a lower depression. When the shuttle piston moves upward, the upper barb can be inserted into the upper depression, and when the shuttle piston moves downward, the lower barb can be inserted into the lower depression.

5. The electrothermal pulse plugging removal tool according to claim 4, characterized in that: The piston cylinder is a cylindrical container.

6. An electrothermal pulse plugging removal tool according to any one of claims 2 to 5, characterized in that: The first action end of the pulse generating device includes a first gas injection pipe and a first heating metal rod, and the second action end includes a second gas injection pipe and a second heating metal rod; The first action end extends into the upper end cavity of the piston cylinder, corresponding to the upper space of the shuttle piston, and the second action end extends into the lower end cavity of the piston cylinder, corresponding to the lower space of the shuttle piston.

7. The electrothermal pulse plugging removal tool according to claim 6, characterized in that: The upper end of the piston cylinder is connected to a faucet, and the upper end of the faucet is connected to a lifting system.

8. The electrothermal pulse plugging removal tool according to claim 6, characterized in that: The pulse generating device is connected to a ground energy supply system.

9. The electrothermal pulse plugging removal tool according to claim 8, characterized in that: The ground energy supply system includes a high-pressure gas supply system and a power supply system, and the power supply system can freely adjust the voltage to make the heating efficiency higher; The power supply is connected to the electric heating metal rod through a cable, and the gas supply device injects gas into the cylindrical cavity through a high-temperature and high-pressure pipeline.

10. An implementation process of an electrothermal pulse plugging removal tool, characterized in that: The following steps are involved: The first step is to lower the plugging removal device into the wellbore through the lifting system so that the gas injection hole corresponds to the wellbore perforation; The second step is to turn on the power supply of the upper heating metal rod and inject gas into the space above the shuttle piston to reach the required pressure. The piston is unhooked from the upper barb and slides to the lower part of the cavity. The gas is ejected through the gas injection port and enters the formation. A pulse action is completed. The third step is to open the heating metal rod and the steam injection port in the space below the piston after one pulse, push the piston upward, and make the lower barb hook the piston, so that the pressure and temperature in the closed space continue to rise. When the unhooking pressure is reached, the piston is pushed upward, and the gas is ejected from the gas injection hole again; The fourth step is to repeat the above steps to continuously deblock the near-wellbore formation for multiple times.

11. The implementation process of the electrothermal pulse plugging removal tool according to claim 10, characterized in that: Before the first step, preparatory steps are performed to connect the ground power supply system and the gas supply system through cables and pipelines, and to check the sealing of the connection of the electric thermal pulse deblocking tool.

12. A special upstream and downstream decoupling piston mechanism for an electrothermal pulse plugging removal tool, characterized in that: It includes a piston cylinder, a shuttle piston, and a rubber protective sealing sleeve; A rubber protective sealing sleeve is arranged on the inner wall of the piston cylinder, a sealing sleeve through hole is arranged in the middle of the rubber protective sealing sleeve, a gas injection hole is arranged in the middle of the piston cylinder, and the sealing sleeve through hole is correspondingly connected with the gas injection hole of the piston cylinder; The outer wall of the shuttle-shaped piston can perform an upward and downward movable intermittent seal with the inner wall of the rubber protective sealing sleeve.

13. The up-and-down moving unhooking type piston mechanism for an electrothermal pulse plugging removal tool according to claim 12, characterized in that: The inner wall of the rubber protective sealing sleeve is provided with an upper inner conical surface and a lower inner conical surface, and the outer wall of the shuttle-shaped piston is provided with an upper outer conical surface and a lower outer conical surface, wherein the upper outer conical surface can fit tightly against the upper inner conical surface, and the lower outer conical surface can fit tightly against the lower inner conical surface.

14. The up-and-down moving unhooking type piston mechanism for an electrothermal pulse plugging removal tool according to claim 13, characterized in that: The inner wall of the piston cylinder is provided with an upper barb obliquely upward and a lower barb obliquely downward; The upper outer conical surface of the shuttle piston is provided with an upper depression, and the lower outer conical surface is provided with a lower depression. When the shuttle piston moves upward, the upper barb can be inserted into the upper depression, and when the shuttle piston moves downward, the lower barb can be inserted into the lower depression.

15. The up-and-down moving decoupling piston mechanism for an electrothermal pulse plugging removal tool according to claim 14, characterized in that: The piston cylinder is a cylindrical container.

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