A pre-shaped set-in recyclable bridge plug and a downhole set-in recovery method

Abstract

This invention discloses a pre-shaped, retrievable bridge plug and a downhole setting and recovery method. The bridge plug comprises a retrievable module, a packer module, and a pre-shaped module coaxially connected from top to bottom. Under controlled load, the pre-shaped module forms a circumferential plastic deformation zone on the wellbore. The packer module completes radial expansion setting within the plastic deformation zone. The retrievable module is recovered as a whole through a retrieval operation. The packer module and the pre-shaped module are fail-safe structures. This invention improves the stress and constraint conditions of the packer sleeve by pre-plastic deformation of the wellbore contact area before setting, thereby enhancing the setting stability and sealing reliability of open-hole sections and sections with poor cement sheathing. Simultaneously, the bridge plug employs a graded triggering and modular structural design, enabling the recovery of key components and rapid failure of the lower structure, reducing downhole residue, and improving operational efficiency and reducing construction costs.

Description

Technical Field

[0001] This invention belongs to the field of bridge plug technology, specifically relating to a pre-shaped set-in recyclable bridge plug and a downhole set-in recovery method. Background Technology

[0002] In oil and gas well completion, staged stimulation, and temporary plugging operations, bridge plug tools are commonly used to isolate different sections of the wellbore. Existing bridge plugs typically rely on the radial expansion of the packer sleeve against the wellbore wall or casing inner wall to form a seal. The sealing effect largely depends on the integrity, strength, and geometric regularity of the wellbore surface. However, in open-hole sections or sections with poor cement sheath quality, the wellbore wall or cement sheath surface often exhibits unevenness, localized looseness, or uneven strength distribution. This leads to uneven stress on the packer sleeve during setting, making it prone to localized extrusion, axial displacement, or unstable sealing.

[0003] For complex well section conditions, existing technologies have attempted to enhance sealing capabilities by increasing the stiffness of packer elements or adopting expansion structures. However, such solutions are often complex in structure, have limited adaptability, and still cannot guarantee a stable and reliable sealing effect when well wall conditions are not ideal.

[0004] Practical experience shows that effective mechanical control or morphological improvement of the wellbore contact area before setting can provide more favorable stress and constraint conditions for the packer element, thus improving packer reliability. Meanwhile, with the increasing demands for operational efficiency and cost control in unconventional oil and gas development, bridge plug tools must not only provide reliable temporary plugging but also possess good recyclability or rapid failure capability to reduce the impact of downhole residues on subsequent operations. Summary of the Invention

[0005] Purpose of the invention: In view of the defects and technical problems existing in the background technology, the present invention provides a pre-shaped set-in retrievable bridge plug and a downhole set-in recovery method.

[0006] Technical Solution: To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a pre-shaped setting type retrievable bridge plug, comprising a retrievable module, a packer module, and a pre-shaped module coaxially arranged from top to bottom. The pre-shaped module can form a circumferential plastic deformation zone on the well wall under controlled load. The packer module completes radial expansion setting within the plastic deformation zone. The retrievable module can be recovered as a whole through a retrieval operation. The packer module and the pre-shaped module are failure-prone structures. The recyclable module includes a first ball seat, a first plugging ball, an outer sleeve, a fishing neck and a retaining ring respectively connected to the upper and lower ends of the outer sleeve. A chute is provided on the inner wall of the outer sleeve. The first ball seat is a conical ring seat with a central opening, and an outer edge thereof is provided with a slider adapted to the chute of the outer sleeve. The first ball seat is inverted and arranged in the outer sleeve and can slide up and down along the chute. The first plugging ball can be placed at the central opening of the first ball seat to form a flow path blockage; when the outer sleeve is lifted, the first ball seat and the first plugging ball can be lifted out through the retaining ring at the bottom end. The packer module includes a packer rubber cylinder, an upper support ring and a lower support ring respectively arranged at the upper and lower ends of the packer rubber cylinder. The packer rubber cylinder is nested on the inner wall of the outer sleeve, and the outer edge of the first ball seat is inverted and arranged on the upper support ring. The pre-shaping module includes a plurality of force transmission guiding rods connected to the bottom end of the lower support ring through pins, the same number of radial shaping components respectively connected to the force transmission guiding rods, a lower joint and a limiting rod; the shaping component is an arc block, the limiting rod is connected to the lower joint and arranged between adjacent shaping components, and a second plugging ball is further arranged on the force transmission guiding rod. When the force transmission guiding rod is subjected to a downward load, it can push the radial shaping component to move axially downward while making the radial shaping component expand and move radially outward.

[0007] Preferably, the outer edge of the first ball seat is a bent outer edge, four chutes are evenly arranged on the inner wall of the outer sleeve, and four sliders adapted to the bent outer edge are arranged on the bent outer edge.

[0008] Preferably, the cross section of the fishing neck is a "tu" shaped structure, and the lower end of the fishing neck is threadedly connected to the inner wall of the outer sleeve.

[0009] Preferably, the packer rubber cylinder can elastically deform under the axial extrusion load of the upper and lower support rings.

[0010] Preferably, the number of the force transmission guiding rods is four. Each force transmission guiding rod includes a guiding rod main body and a connecting rod. One end of the guiding rod main body is fixed to the lower support ring through a pin, the other end is a free end and is arranged to incline downward; one end of the connecting rod is connected to the middle of the guiding rod, and the other end is connected to the shaping component. The packer module and the pre-shaping module are made of soluble or quickly failing materials.

[0011] The present invention also provides a downhole setting and recovery method based on the above pre-shaped setting retrievable bridge plug, including the following steps: S1. Lower the pre-shaped setting retrievable bridge plug to the target open hole section or the section with insufficient cement sheath integrity through a pipe string. In the initial state, the recyclable module, the packer module and the pre-shaping module are all in a retracted state, the radial shaping components are shielded by the outer sleeve, and the flow path in the bridge plug remains unblocked. S2, the second plugging ball is dropped into the well. The second plugging ball goes down along the inner flow channel and forms a sealed fit with the force transmission guide rod of the pre-shaping module. The pressure inside the tubing gradually increases, generating an axial load, which pushes the outer sleeve to produce an axial displacement, thus releasing the radial shielding of the radial shaping component. S3, the axial load is transmitted to the radial shaping component through the force transmission guide rod and connecting rod, so that the radial shaping component extends radially along the limiting rod and contacts the well wall. Under the action of the controlled load, pressure is applied to the surface of the well wall, so that the well wall forms a circumferential plastic deformation zone, which is used to trigger the pre-shaping module, so that the radial shaping component extends and completes the pre-shaping of the well wall. S4, the first plugging ball is dropped into the well. The first plugging ball moves down along the inner flow channel and cooperates with the first ball seat to block the bridge plug flow channel. Pressurization continues to be applied into the tubing string to make the upper support ring move downward along the axis, which is used to trigger the packer module, so that the upper support ring compresses the packer sleeve and completes the setting seal. S5. The upper support ring moves downward to apply an axial compressive load to the packer, causing the packer to bulge radially within the circumferential plastic deformation zone of the well wall. Through the clamping and limiting of the lower and upper support rings, the packer fits into the plastic deformation zone to form a well wall seal. S6. After the bridge plug completes the temporary plugging operation in the wellbore, the retrievable module is retrieved as a whole by using the retrieval tool and the retrieval neck. S7, the packer module and the pre-shaping module gradually fail under predetermined wellbore medium, temperature or time conditions, completing the entire wellbore packing and unpacking operation.

[0012] Preferably, the radial shaping component 12 has a shaping depth of 5-10 mm and a shaping width of 80-120 mm.

[0013] Beneficial effects: Compared with the prior art, the present invention improves the stress and limiting conditions of the packer by pre-plastic deformation of the well wall contact area before setting, thereby improving the setting stability and sealing reliability of open hole sections and sections with poor cement sheath. The bridge plug of the present invention adopts a graded triggering and modular structure design, realizing the recovery of key components and rapid failure of the lower structure, reducing downhole residues, which is conducive to improving operation efficiency and reducing construction costs. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the pre-shaped seated recyclable bridge plug described in this invention.

[0015] Figure 2 This is a schematic diagram of the pre-shaped seated recyclable bridge plug described in this invention under axial load.

[0016] Among them, the salvage neck 1, upper connector 2, first ball seat 3, first sealing ball 4, upper support ring 5, sealing rubber tube 6, outer sleeve 7, lower support ring 8, second sealing ball 9, force transmission guide rod 10, connecting rod 1001, pin 11, radial shaping component 12, guide rod 13, lower connector 14, and inner flow channel 15 are included. Detailed Implementation

[0017] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. After reading this invention, any modifications of the invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0018] like Figure 1 and 2 As shown, the core components of the pre-shaped, set-sealed, recyclable bridge plug of the present invention mainly include: a recyclable module, a packer module, and a pre-shaped module, wherein: The recoverable module includes a retrieval neck 1, an upper connector 2, a first ball seat 3, a first plugging ball 4, and an outer sleeve 7. The retrieval neck 1 is a rod-shaped structure (with a U-shaped cross-section for easy lifting and retrieval). Its upper end has a retrieval mating part for engaging with downhole retrieval tools, and its lower end is threadedly connected to the upper connector 2. The upper connector 2 connects to both the upper tubing string and the lower outer sleeve 7, serving as a channel for transmitting axial loads and pressure. The inner wall of the outer sleeve 7 is integrally formed with the first ball seat 3, which is a spherical seat that matches the first plugging ball 4. After the first plugging ball 4 is deployed, it fits tightly against the first ball seat 3, sealing the flow channel 15 within the bridge plug. The entire recoverable module is coaxial with the first ball seat 3 and remains connected to the upper tubing string after the bridge plug is set, ensuring subsequent overall retrieval.

[0019] The packer module includes a packer sleeve 6, an upper support ring 5, and a lower support ring 8. The packer sleeve 6 is made of a high-pressure resistant and wear-resistant elastic sealing material. The packer sleeve 6 is fitted inside the outer sleeve 7, with its upper and lower ends fixedly connected to the upper support ring 5 and the lower support ring 8, respectively. The upper and lower support rings 5 ​​and 8 clamp and limit the packer sleeve 6 axially. The upper support ring 5 can move downwards axially along the outer sleeve 7. When compressed, it applies a uniform axial compressive load to the packer sleeve 6, causing it to radially expand. The lower support ring 8 is an integrally formed structure with the pre-forming module and can move axially with it. It provides axial limitation for the packer sleeve 6 and acts as a radial guide during expansion, ensuring the packer sleeve 6 is precisely embedded into the circumferential plastic deformation zone of the well wall.

[0020] The pre-shaping module includes a second sealing ball 9, an interception structure, a force transmission guide rod 10, guide rods 13, a connecting rod 1001, and a radial shaping assembly 12. The interception structure is located at the inner flow channel 15 at the lower end of the outer sleeve 7. It is a spherical interception seat that matches the second sealing ball 9, enabling a sealing fit with the second sealing ball 9 to partially block the inner flow channel 15. The lower end of the lower support ring 8 is vertically fixed with a force transmission guide rod 10 and multiple guide rods 13. The guide rods 13 are evenly distributed along the circumference of the bridge plug. The radial shaping assembly 12 is horizontally slidably connected to the guide rods 13, ensuring that the radial shaping assembly 12 can only move radially. The force transmission guide rod 10 and the radial shaping assembly 12 are fixedly connected by the connecting rod 1001 to achieve precise transmission of axial load. The radial shaping assembly 12 consists of four radial shaping blocks evenly distributed circumferentially along the bridge plug axis. The outer side of the shaping block is an arc-shaped shaping working surface, which can achieve uniform circumferential loading when in contact with the well wall. The inner side is connected to the force transmission guide rod 10 through the connecting rod 1001.

[0021] The pre-shaping module of this invention is not simply an expansion or anchoring structure, but is used to improve the contact conditions with the well wall, providing radial restraint and axial anti-slip constraint for the rubber sleeve, thereby solving the problems of uneven stress, local extrusion, axial displacement and unstable sealing of the rubber sleeve in open hole sections or sections with poor cement sheath.

[0022] The force transmission guide rod 10 is fixedly connected to the lower support ring 8 via a pin 11. In the initial state, the pin 11 forms a rigid limit and fixation on the sleeve 7 and the guide rod 13, firmly locking the radial shaping component 12 in a closed and shielded state inside the outer sleeve 7. This can effectively withstand various conventional interference loads during the insertion of the bridge plug, prevent the outer sleeve 7 from prematurely displacing axially and the radial shaping component 12 from accidentally extending, and completely eliminate the premature triggering of the pre-shaping action from a structural perspective.

[0023] When the bridge plug is precisely driven into the target well section, the second plugging ball 9 is deployed and pressurized to the preset pressure threshold, the axial load generated inside the tubing can shear off the pin 11, releasing the limiting constraints on the relevant components. This allows the outer casing 7 to achieve axial displacement, the radial shaping component 12 to extend normally, and the well wall pre-shaping action to be initiated. This not only protects the shaping working surface of the radial shaping component 12 from being scratched and damaged by the well wall, but also avoids downhole accidents such as tubing blockage and stuck drill bit caused by accidental extension of components. This ensures the accuracy, safety, and controllability of the bridge plug driving and triggering operation in complex well sections.

[0024] In the initial state, the radial shaping component 12 is concealed by the outer sleeve 7 and is in a retracted state. After the outer sleeve 7 undergoes axial displacement, the concealment state is released, and the radial shaping component 12 can extend radially along the guide rod 13 under axial load.

[0025] In this embodiment, the packer sleeve 6, upper support ring 5, lower support ring 8 of the packer module, and all components of the pre-shaped module are made of oilfield-specific soluble alloys or biodegradable polymer materials. These are fail-safe structures that can self-dissolve under the temperature and medium conditions of the wellbore, and the residual size after dissolution is much smaller than the wellbore diameter, thus not affecting subsequent drilling and completion operations. The retrieval neck 1, upper connector 2, first ball seat 3, and other components of the recyclable module are made of high-strength alloy steel and can be recycled and reused multiple times.

[0026] The specific usage methods for pre-molded, recyclable bridge plugs include: The pre-shaped set-and-recoverable bridge plug is lowered as a whole into the target open hole section or section of the oil and gas well where the cement sheath is not intact through the upper tubing string. In the initial state, the recoverable module, the packer module, and the pre-shaped module are all in a retracted state. The radial shaping component 12 is completely covered by the outer casing 7. The internal flow channel 15 of the bridge plug remains unobstructed, and the fluid in the tubing string can circulate normally.

[0027] A second plugging ball 9 is inserted into the well. Driven by the fluid within the tubing, the second plugging ball 9 descends along the inner flow channel 15, eventually sealing against the interception structure of the pre-shaping module, thus partially blocking the inner flow channel 15. As the fluid within the tubing is unable to pass through normally, the pressure within the tubing gradually increases, generating an axially downward load. This load pushes the outer casing 7 to displace axially downward, releasing the radial shielding of the radial shaping component 12 by the outer casing 7.

[0028] The axial load within the tubing string is uniformly transmitted to the radial shaping assembly 12 via the force transmission guide rod 10 and connecting rod 1001. This pushes four radial shaping blocks to extend radially synchronously along the guide rod 13, with the arc-shaped shaping working surface of the blocks contacting the wellbore surface. As the tubing string pressure continues to increase slowly, the radial shaping assembly 12 applies non-cutting, non-penetrating circumferential pressure to the wellbore surface under controlled load, causing plastic deformation and forming a circumferential plastic deformation band distributed along the wellbore circumference. The shaping depth and width of this plastic deformation band are jointly controlled by the geometric dimensions of the radial shaping blocks and the tubing string loading pressure. This can be adjusted in advance according to the wellbore material and strength parameters of the target well section. In this embodiment, the shaping depth is controlled between 5 and 10 mm, and the shaping width is controlled between 80 and 120 mm to avoid destructive damage to the wellbore.

[0029] After the wellbore pre-shaping is completed, the first plugging ball 4 is inserted into the well. The first plugging ball 4 moves down along the inner flow channel 15 and fits tightly with the first ball seat 3, achieving complete plugging of the bridge plug inner flow channel 15. Pressurization continues to be applied into the tubing string, and the pressure pushes the upper support ring 5 to move axially downward along the outer sleeve 7.

[0030] When the upper support ring 5 moves downward, it applies a uniform axial compressive load to the packer sleeve 6. Under the clamping and limiting effect of the upper support ring 5 and the lower support ring 8, the packer sleeve 6 undergoes radial expansion and precisely embeds itself into the circumferential plastic deformation zone of the well wall. The circumferential plastic deformation zone provides radial limiting and axial anti-slip constraint for the packer sleeve 6, ensuring a tight fit between the packer sleeve 6 and the well wall, forming a stable and reliable wellbore seal, and achieving isolation of the target well section. After the ball is dropped, the clamping action of the upper and lower support rings on the sleeve causes the sleeve to expand radially under pressure and embed itself into the aforementioned circumferential plastic deformation zone, demonstrating the direct contribution of the pre-shaping action to the subsequent sealing effect.

[0031] After the bridge plug completes the temporary plugging operation in the wellbore, the retrieval tool is lowered through the upper tubing string. After the retrieval tool engages with the retrieval mating part of the retrieval neck 1, the tubing string is raised upwards to retrieve the retrieval neck 1, upper connector 2, first ball seat 3 and other components of the recyclable module as a whole, thus completing the recycling and reuse of the recyclable components.

[0032] This invention employs a tiered triggering logic: the second plugging ball is deployed first to trigger the pre-shaping module, causing the radial shaping component to extend and complete the wellbore pre-shaping; the first plugging ball is deployed later to trigger the packer module, causing the upper support ring to compress the packer sleeve and complete the setting seal. Therefore, this invention adopts a "shape first, seal later" technical approach.

[0033] In this invention, the forming depth is 5-10 mm, the forming width is 80-120 mm, and multiple circumferentially evenly distributed arc-shaped forming blocks are formed. The outer side is an arc-shaped forming working surface. The load is applied to the surface of the well wall in a non-cutting and non-penetrating manner (to avoid causing destructive damage to the main structure of the well wall), forming a circumferentially uniform circumferential plastic deformation zone.

[0034] In this invention, the upper recyclable module adopts a salvageable and reusable structure, while the lower sealing module and pre-shaping module adopt a partitioned design using soluble or rapidly deteriorating materials.

[0035] After the recyclable module is retrieved, the soluble and biodegradable materials of the packer module and the pre-shaped module gradually dissolve and fail under the temperature of the wellbore and the action of the drilling fluid medium. No hard residue falls off during the dissolution process, and the size of the residual structure is much smaller than the wellbore diameter, so it does not affect subsequent oil and gas well operations. This completes the entire wellbore packing and unpacking process.

[0036] In this embodiment, the beneficial effects of the pre-shaped set recyclable bridge plug include at least the following: This solution is specifically designed to address the operational challenges of open-hole sections or sections with poor cement sheath quality. It effectively solves problems such as uneven setting stress, localized extrusion, axial displacement, and unstable sealing caused by uneven wellbore or cement sheath surfaces, localized looseness, or uneven strength distribution. The radial shaping component 12, before setting, creates a circumferential plastic deformation zone in the wellbore contact area. This zone, through controlled loads, fills localized undulations and depressions in the wellbore, achieving circumferential compaction and structural restraint on loose areas of the cement sheath or wellbore, thus fixing the originally irregular and unevenly strengthened wellbore. The contact surface is modified into a regular, uniformly stressed sealing mating surface, so that when the packer sleeve 6 expands within the deformation zone, it can achieve circumferential uniform contact with the well wall, completely avoiding the extrusion of the sleeve due to excessive local contact stress. At the same time, the circumferential structure constraint of the circumferential plastic deformation zone and the axial limiting effect of the support ring 8 can effectively prevent the packer sleeve 6 from axially shifting during pressure or differential pressure changes. This fundamentally improves the sealing environment of the packer sleeve 6 in open hole sections and sections with poor cement sheath, and significantly enhances the stability, reliability and long-term effectiveness of the bridge plug seal under such complex working conditions.

[0037] By performing pre-plastic deformation on the wellbore contact area before setting, the stress and constraint conditions of the packer sleeve 6 are improved, enhancing the setting stability and sealing reliability of open-hole sections and sections with poor cement sheath conditions. Simultaneously, the adoption of a graded triggering and modular structural design enables the recovery of key components and rapid failure of the lower structure, reducing downhole residue and improving operational efficiency while lowering construction costs. Furthermore, the wellbore pre-plastic deformation mechanism introduced in the bridge plug setting process in this embodiment breaks through the existing technical route of bridge plugs relying entirely on the natural state of the wellbore for sealing.

[0038] The radial shaping component 12 can form a circumferential plastic deformation zone on the well wall before setting, actively improving the contact and stress conditions of the packer sleeve 6. In conjunction with the guiding and limiting function of the lower support ring 8, it can prevent the packer sleeve 6 from being locally extruded or axially displaced due to irregularities in the well wall, thus significantly improving the setting stability and sealing reliability of open hole sections and sections with poor cement sheath.

[0039] By using the staged deployment of the second plugging ball 9 and the first plugging ball 4, and the staged pressurization of the tubing string, the wellbore pre-shaping of the pre-shaping module and the rubber sleeve setting of the packer module are triggered in stages, avoiding interference between the two actions and improving the controllability of on-site operations and the accuracy of action execution.

[0040] The recyclable module, consisting of salvage neck 1 and upper connector 2, remains connected to the upper tubing. After the operation, it can be retrieved as a whole using salvage tools. Furthermore, the core components are made of high-strength alloy steel and can be reused multiple times, effectively reducing the cost of tool use.

[0041] The radial shaping component 12 applies a non-cutting, non-penetrating controlled load to the well wall, causing plastic deformation only on the surface of the well wall. This improves the sealing contact conditions while avoiding destructive damage to the main structure of the well wall, thus ensuring the integrity of the well structure.

[0042] The upper support ring 5 and the lower support ring 8 form a clamping structure on the sealing rubber cylinder 6 in the axial direction, so that the sealing rubber cylinder 6 expands radially uniformly after being squeezed, and the circumferential plastic deformation zone forms radial limit and axial anti-slip constraint on the outer bulge of the sealing rubber cylinder 6, which further improves the stability and pressure bearing capacity of the wellbore seal.

[0043] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A pre-shaped, set-sealed, recyclable bridge plug, characterized in that: It includes a recyclable module, a packer module, and a pre-shaping module that are coaxially arranged from top to bottom in sequence. The pre-shaping module can form a circumferential plastic deformation zone on the wellbore under the action of a controlled load. The packer module completes radial expansion and setting within the plastic deformation zone. The recyclable module can be integrally recovered through fishing operations. The packer module and the pre-shaping module are fail-safe structures; The recyclable module includes a first ball seat, a first plugging ball, an outer sleeve, a fishing neck and a retaining ring respectively connected to the upper and lower ends of the outer sleeve. A chute is provided on the inner wall of the outer sleeve. The first ball seat is a conical ring seat with a central opening, and an outer edge thereof is provided with a slider adapted to the chute of the outer sleeve. The first ball seat is inverted and arranged in the outer sleeve and can slide up and down along the chute. The first plugging ball can be placed at the central opening of the first ball seat to form a flow path plugging; when the outer sleeve is lifted, the first ball seat and the first plugging ball can be lifted out through the retaining ring at the bottom end; The packer module includes a packer rubber cylinder, an upper support ring and a lower support ring respectively provided at the upper and lower ends of the packer rubber cylinder. The packer rubber cylinder is nested on the inner wall of the outer sleeve, and the outer edge of the first ball seat is inverted and arranged on the upper support ring; The pre-shaping module includes a plurality of force transmission and guiding rods connected to the bottom end of the lower support ring by pins, the same number of radial shaping components respectively connected to the force transmission and guiding rods, a lower sub and a limiting rod; the shaping component is an arc block, the limiting rod is connected to the lower sub and arranged between adjacent shaping components, and a second plugging ball is further provided on the force transmission and guiding rod, When the force transmission and guiding rod is subjected to a downward load, it can push the radial shaping component to move axially downward while making the radial shaping component expand and move radially outward; The number of the force transmission and guiding rods is four. Each force transmission and guiding rod includes a guiding rod main body and a connecting rod. One end of the guiding rod main body is fixed to the lower support ring by a pin, and the other end is a free end and is inclined downward; one end of the connecting rod is connected to the middle of the guiding rod main body, and the other end is connected to the shaping component; The packer module and the pre-shaping module are made of materials that can quickly fail.

2. The pre-shaped, set-sealed, recyclable bridge plug according to claim 1, characterized in that: The outer edge of the first ball seat is a bent outer edge, and four chutes are evenly provided on the inner wall of the outer sleeve, and four sliders adapted to the bent outer edge are provided on the bent outer edge.

3. The pre-shaped, set-sealed, recyclable bridge plug according to claim 1, characterized in that: The cross-section of the fishing neck is a "tu" shaped structure, and the lower end of the fishing neck is threadedly connected to the inner wall of the outer sleeve.

4. The pre-shaped, set-sealed, recyclable bridge plug according to claim 1, characterized in that: The packer rubber cylinder can elastically deform under the axial extrusion load of the upper and lower support rings.

5. A downhole setting and recovery method based on the pre-shaped set retrievable bridge plug according to any one of claims 1-4, characterized in that... It includes the following steps: S1. Lower the pre-shaping setting type recyclable bridge plug into the target open hole section or the section with insufficient cement sheath integrity through a pipe string. In the initial state, the recyclable module, the packer module and the pre-shaping module are all in a retracted state, the radial shaping components are shielded by the outer sleeve, and the inner flow path of the bridge plug remains unobstructed; S2. Drop a second plugging ball into the well. The second plugging ball descends along the inner flow path and forms a sealing fit with the force transmission and guiding rod of the pre-shaping module. The pressure in the pipe string gradually increases to generate an axial load, which pushes the packer rubber cylinder to generate an axial displacement, and解除外套管对径向塑形组件的径向遮蔽; (It seems there is an error in this part of the Chinese text. It might be "解除外套管对径向塑形组件的径向遮蔽作用" which could be translated as "解除 the shielding effect of the outer sleeve on the radial shaping components") S3, the axial load is transmitted to the radial shaping component through the force transmission guide rod, causing the radial shaping component to extend radially along the limit rod and contact the well wall. Under the action of the controlled load, pressure is applied to the surface of the well wall, causing the well wall to form a circumferential plastic deformation zone. By triggering the pre-shaping module, the radial shaping component extends and completes the pre-shaping of the well wall. S4, the first plugging ball is dropped into the well. The first plugging ball moves down along the inner flow channel and cooperates with the first ball seat to block the inner flow channel of the bridge plug. Continue to pressurize the tubing string to make the upper support ring move downward along the axis, which is used to trigger the packer module, so that the upper support ring compresses the packer rubber sleeve and completes the setting seal. S5. The upper support ring moves downward to apply an axial compressive load to the packer, causing the packer to bulge radially within the circumferential plastic deformation zone of the well wall. Through the clamping and limiting of the lower and upper support rings, the packer fits into the plastic deformation zone to form a well wall seal. S6. After the bridge plug completes the temporary plugging operation in the wellbore, the retrievable module is retrieved as a whole by using the retrieval tool and the retrieval neck. S7, the packer module and the pre-shaping module gradually fail under predetermined wellbore medium, temperature or time conditions, completing the entire wellbore packing and unpacking operation.

6. The downhole setting and recovery method for the molded setting type retrievable bridge plug according to claim 5, characterized in that: The radial shaping component has a shaping depth of 5-10 mm and a shaping width of 80-120 mm.

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