Rupture disc type fully-soluble bidirectional anchoring plugging bridge plug and method

Abstract

The invention discloses a rupture disc type full-soluble bidirectional anchoring plugging bridge plug and a method. The rupture disc type full-soluble bidirectional anchoring plugging bridge plug comprises a push cylinder, a push cylinder pressing cylinder, a mandrel, a cone and a guide head assembly which are sequentially connected. The rupture disk is arranged at the step in the seeker assembly; the mandrel penetrates through the cone, one end of the mandrel is connected with the seeker assembly through a shear pin and faces the rupture disc, and the other end of the mandrel is connected with the push cylinder through threads. After fracturing or perforation is completed, when a wellhead has pressure, a cable or a continuous oil pipe is firstly tripped into the well by a designed depth, a shaft is blocked in a short time, the pressure of the wellhead is released, so that the section of a bridge plug and the wellhead is free of pressure, then wellhead replacement and conventional operation are completed, a production pipe column is tripped into the well by the designed depth, and the production wellhead is installed. And finally, pressing the wellhead to crush a rupture disk in the soluble bridge plug, so that the bridge plug is communicated up and down, the well can be put into production at the first time, and a full-bore shaft is realized along with the dissolution of the soluble bridge plug subsequently.

Description

Technical Field

[0001] The present invention belongs to the field of oil and gas and other energy operations, and particularly relates to a rupture disk type fully soluble bi-directional anchoring plugging bridge plug and method. Background Art

[0002] In the field of oil and gas production, whether it is drilling and completion or workover operations, there are many types of wellbore plugging tools, and their uses are also diverse according to operation requirements. Permanent packer plugging, retrievable temporary packer plugging, soluble bridge plugs, etc. are widely used and have very remarkable effects. After completion or workover, the production or test string can be run in the well under pressure without killing the well, which has the advantages of protecting the oil and gas reservoir and reducing formation pollution, and is increasingly favored by oilfields.

[0003] At present, after fracturing or perforating, there are two operation methods for the production or test string in the oil and gas well with wellhead pressure. One is to directly lower the production string into the well by a workover rig under pressure, and the other is to run the production or test string under normal operation after killing the well smoothly. Running the production string under pressure with a workover rig has good reliability and safety, but the workover rig is costly and the operation cycle is long; normal operation requires killing the well smoothly, increasing the killing cost and easily causing secondary formation pollution. If a non-channel soluble bridge plug is used, the formation cannot be communicated until the bridge plug dissolves, and the formation cannot be communicated immediately (and there is a risk of blocking the tubing after dissolution), resulting in a long waiting time for production. Is there a plugging bridge plug that can communicate with the formation immediately after the production string is run into the well, and there is no need to wait for the dissolution time subsequently, improving the operation efficiency, reducing costs and increasing efficiency, which has become an urgent problem to be solved on site. Summary of the Invention

[0004] In view of this, the main object of the present invention is to provide a rupture disk type fully soluble bi-directional anchoring plugging bridge plug and method.

[0005] To achieve the above object, the technical solution of the present invention is realized as follows:

[0006] A rupture disk type fully soluble bi-directional anchoring plugging bridge plug includes a push barrel, a push barrel compression barrel, a mandrel, a cone, and a guide head assembly connected in sequence;

[0007] It further includes a rupture disk disposed at the internal step of the guide head assembly;

[0008] The mandrel is inserted through the cone, one end is connected to the guide head assembly through a shear pin and faces the rupture disk, and the other end is connected to the push barrel through a thread.

[0009] Preferably, the mandrel is provided with an annular shear groove, the annular shear groove is combined with the shear pin, and the shear strength of the shear pin is designed as the shear force value required for the bridge plug to be separated from the push barrel after setting.

[0010] Preferably, it further includes a bi-directional anchoring slips body, which is divided into a plurality of expandable block units through slotted grooves, and is internally provided with a conical hole for cooperating with the cone.

[0011] Preferably, the block units of the bi-directional anchoring slips body are provided with bi-directionally distributed teeth, and the depth of the slotted grooves between adjacent block units is 70-85% of the wall thickness of the slips body. The bi-directional anchoring slips body forms a bi-directional anchor with the casing wall through the bi-directionally distributed teeth.

[0012] Preferably, the guide head assembly includes a guide head and a connecting cylinder. The guide head and the bi-directional anchoring slips body are connected through the connecting cylinder. The guide head is provided with a step, and the bowl mouth of the rupture disc is buckled on the step to limit the axial movement of the rupture disc.

[0013] Preferably, it further includes an outer rubber cylinder and a protective bowl. The outer rubber cylinder and the protective bowl are sequentially sleeved on the large outer diameter section of the cone and are positioned through a spacer ring.

[0014] Preferably, it further includes an inner rubber cylinder, which is fixed to the inner cavity of the connecting cylinder through fixing screws, and the inner diameter is smaller than the small outer diameter section of the cone.

[0015] Preferably, the rupture disc has a bowl-shaped structure, the pressure resistance strength of the bowl mouth end is greater than that of the bowl bottom end, and the critical rupture pressure is 15-35 MPa.

[0016] Preferably, the inner cavity of the connecting cylinder is provided with a stepped sealing groove, and the end of the inner rubber cylinder is press-fitted and fixed in the stepped sealing groove through fixing screws.

[0017] A wellbore plugging method for a rupture disc type fully soluble bi-directional anchoring plugging bridge plug, and the method is as follows:

[0018] Lower the bridge plug to the designed position in the well through a cable or coiled tubing, and connect the push cylinder with the setting tool.

[0019] Apply hydraulic thrust through the setting tool to push the cone to move forward along the mandrel, so that the block units of the bi-directional anchoring slips body expand and embed into the casing wall to form a bi-directional anchor. At the same time, compress the outer rubber cylinder and the inner rubber cylinder of the guide head to form a seal.

[0020] When the hydraulic pressure reaches the set value, the shear pin breaks, so that the mandrel is separated from the guide head, and the setting of the bridge plug is completed.

[0021] After the wellhead pressure is relieved to a non-pressure state, replace the wellhead and lower the production string.

[0022] Pressurize the wellhead to 15-35 MPa to break the rupture disc to form a central fluid passage.

[0023] Realize the up and down communication of the wellbore through the passage and put it into production immediately.

[0024] After the soluble component of the bridge plug dissolves, the full bore of the wellbore is restored.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] After fracturing or perforating, when there is pressure at the wellhead, the present invention uses a cable or coiled tubing to first lower it to the designed depth in the well, short-term plug the wellbore, release the wellhead pressure to make the section between the bridge plug and the wellhead pressure-free, then complete the wellhead replacement, conventional operation to lower the production string to the designed depth in the well, install the production wellhead, and finally apply pressure at the wellhead to crush the rupture disc in the soluble bridge plug, making the upper and lower parts of the bridge plug communicate. Immediately, the production of this well can be realized. Subsequently, as the soluble bridge plug dissolves, a full-bore wellbore is achieved. This operation method greatly reduces the comprehensive operation cost and significantly improves the operation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to disclose a further understanding of the present invention and form a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0028] Figure 1 is a schematic structural diagram of a rupture-disc type fully soluble bi-directional anchoring plugging bridge plug provided by an embodiment of the present invention;

[0029] Figure 2 is Figure 1 a cross-sectional view taken along line A-A in

[0030] In the figure, 1, rupture disc; 2, push cylinder; 3, push cylinder pressure cylinder; 4, mandrel; 5, cone; 6, protection bowl; 7, rubber cylinder; 8, spacer ring; 9, bi-directional anchoring slip body; 10, shear pin; 11, guide head; 12, inner rubber cylinder; 13, cup head screw; 14, sealing O-ring; 15, fixing screw; 16, connecting cylinder. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] In the drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components; in the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only for illustrative purposes and should not be construed as a limitation of this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0033] It should be noted that in this article, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such a process, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, article or device including that element.

[0034] An embodiment of the present invention provides a rupture disk type fully soluble bi-directional anchored plugging bridge plug, as Figure 1 , 2 shown, which includes a push barrel 2, a push barrel pressure barrel 3, a mandrel 4, a cone 5, and a guide head assembly connected in sequence;

[0035] It further includes a rupture disk 1, which is arranged at the internal step of the guide head assembly;

[0036] The mandrel 4 is inserted into the cone 5, one end is connected to the guide head assembly through a shear pin 10 and faces the rupture disk 1, and the other end is connected to the push barrel 2 through a thread.

[0037] After fracturing or perforating in the present invention, when there is pressure at the wellhead, it is first lowered into the designed depth in the well by cable or coiled tubing to temporarily plug the wellbore, release the wellhead pressure to make the section between the bridge plug and the wellhead pressureless, then complete the wellhead replacement, perform conventional operations to lower the production string into the designed depth in the well, install the production wellhead, and finally apply pressure at the wellhead to crush the rupture disk in the soluble bridge plug, so that the upper and lower parts of the bridge plug are connected, and the production of the well can be realized immediately. Subsequently, as the soluble bridge plug dissolves, a full-bore wellbore is achieved, and the comprehensive operation cost of this operation method is greatly reduced, and the operation efficiency is greatly improved.

[0038] The mandrel 4 is provided with an annular shear groove, and the annular shear groove is combined with the shear pin 10. The shear strength of the shear pin 10 is designed as the shear force value required for the bridge plug to be separated from the push barrel 2 after setting.

[0039] The front part of the seeker assembly is chamfered to play a guiding role. It has a step inside for placing the rupture disc 1, and a sealing groove is provided at the inner diameter in contact with the rupture disc 1. The gap between the rupture disc 1 and the seeker assembly is sealed by the sealing ring 14, thus playing a sealing role.

[0040] Furthermore, it also includes a bi-directional anchoring slip body 9. The bi-directional anchoring slip body 9 is divided into multiple expandable block units by slotted grooves, and a tapered hole for cooperating with the cone 5 is provided inside.

[0041] The block units of the bi-directional anchoring slip body 9 are provided with bi-directionally distributed teeth. The depth of the slotted groove between adjacent block units is 70 - 85% of the wall thickness of the slip body. The bi-directional anchoring slip body 9 forms a bi-directional anchoring with the casing wall through the bi-directionally distributed teeth.

[0042] When the block units of the bi-directional anchoring slip body 9 expand outward, they will move upward along the screw part of the socket head screw 13 while the socket head screw 13 remains stationary, so that the bi-directional anchoring slip body 9 will not separate from the connecting cylinder 16.

[0043] The bi-directional anchoring slip body 9 is a double-slip anchoring with bi-directional teeth that can withstand up and down pressures.

[0044] Of course, the bi-directional anchoring slip body 9 can also adopt a single-slip anchoring with teeth that can withstand pressure in a single direction.

[0045] Furthermore, the seeker assembly includes a seeker 11 and a connecting cylinder 16. The seeker 11 and the bi-directional anchoring slip body 9 are connected through the connecting cylinder 16.

[0046] The shear pin 10 passes through the connecting cylinder 16 and is connected to the mandrel 4.

[0047] Furthermore, a sealing ring 14 is also provided between the shear pin 10 and the connecting cylinder 16, and a sealing ring 14 is also provided in the gap between the rupture disc 1 and the seeker 11.

[0048] The seeker 11 is connected to the connecting cylinder 16 by a thread. A clamping groove is provided on the other side of the connecting cylinder 16 for clamping and hanging the bi-directional anchoring slip body 9. A shear pin hole is provided on the outer diameter of the connecting cylinder 16, and a sealing ring 14 for sealing the shear pin 10 is provided, and a socket head screw thread groove is provided for connecting the socket head screw 13.

[0049] Furthermore, it also includes an outer rubber cylinder 7 and a protection bowl 6. The outer rubber cylinder 7 and the protection bowl 6 are sequentially sleeved on the large outer diameter section of the cone 5 and are positioned by a spacer ring 8.

[0050] Exemplarily, the outer rubber cylinder 7 is made of a magnesium-aluminum alloy-based soluble elastic material and completely dissolves within 72 - 240 hours in the wellbore fluid environment.

[0051] Further, it also includes an inner rubber cylinder 12, and the inner rubber cylinder 12 is fixed to the inner cavity of the connecting cylinder 16 by fixing screws 15, and its inner diameter is smaller than the small outer diameter section of the cone 5.

[0052] Exemplarily, the interference fit amount between the small outer diameter section of the cone 5 and the inner rubber cylinder 12 is 0.5 - 1.2 mm, forming a metal - elastomer composite sealing structure.

[0053] The inner cavity of the connecting cylinder 16 is provided with a stepped sealing groove, and the end of the inner rubber cylinder 12 is press - fitted and fixed in the stepped sealing groove by fixing screws 15.

[0054] Further, the rupture disk 1 has a bowl - like structure, and the pressure - resistant strength of the bowl - mouth end is greater than that of the bowl - bottom end, and the critical rupture pressure is 15 - 35 MPa.

[0055] The rupture disk 1 is made of ceramic material, for example, alumina ceramic (Al2O3), zirconia ceramic (ZrO2), silicon nitride ceramic (Si3N4), silicon carbide ceramic (SiC) can be used.

[0056] Further, the block - shaped units of the bi - directional anchoring slips body 9 are provided with bi - directionally distributed teeth, and the slot depth between adjacent block - shaped units is 70 - 85% of the wall thickness of the slips body.

[0057] Further, the inner cavity of the connecting cylinder 16 is provided with a stepped sealing groove, and the end of the inner rubber cylinder 12 is press - fitted and fixed in the stepped sealing groove by socket - head cap screws 13.

[0058] The guide head 11 is provided with a spiral flow - guiding groove, and its flow - guiding angle is 30 - 45 degrees.

[0059] Further, the chamfered side of the protection bowl 6 is provided with radial reinforcing ribs, and its flat side forms a surface contact with the end face of the outer rubber cylinder 7.

[0060] The working process of the present invention is as follows:

[0061] Tool lowering: The bridge plug is transported to the designed downhole position through a cable or coiled tubing. The push cylinder 2 is connected to a setting tool (such as a hydraulic setting tool), and the mandrel 4 is fixed to the connecting cylinder 16 by shear pins 10.

[0062] Bi - directional anchoring start: The setting tool applies a hydraulic thrust to push the cone 5 forward along the mandrel 4. The conical part of the cone 5 squeezes open the block - shaped units of the bi - directional anchoring slips body 9, causing it to expand outwards and embed into the casing wall, and achieving up - and - down bi - directional anchoring (resisting bi - directional wellbore pressures) through bi - directional teeth.

[0063] Seal formation: When the cone 5 moves forward, its large outer diameter section expands and supports the protection bowl 6, the outer rubber cylinder 7 and the spacer ring 8, causing the outer rubber cylinder 7 to expand and seal the casing annulus; at the same time, the small outer diameter section of the cone 5 inserts into the inner rubber cylinder 12 of the connecting cylinder 16, squeezing the inner rubber cylinder 12 to form an internal seal, preventing fluid from leaking through the slots of the bi-directional anchoring slip body 9.

[0064] Tool detachment: When the setting pressure of the packer is reached, the shear pin 10 breaks, the mandrel 4 is detached from the connecting cylinder 16, and the push cylinder tool carries the mandrel up to the wellhead, and the bridge plug is independently anchored in the wellbore.

[0065] Pressure isolation: The bi-directional anchoring slip body 9 and the outer rubber cylinder 7 act together to isolate the wellbore pressure above and below the bridge plug, achieving short-term plugging. At this time, the rupture disk 1 acts as a temporary barrier to seal the central channel of the connecting cylinder 16.

[0066] Wellhead pressure relief: After pressure is released at the wellhead, the wellhead and the wellbore section of the bridge plug are in a non-pressure state, allowing the wellhead to be safely replaced or a production string to be conventionally run in.

[0067] Stimulation pressure to break the rupture disk: After the production string is run in place, pressure is applied to the wellhead to the critical pressure (15 - 35 MPa) of the rupture disk 1. The bottom end (low-pressure side) of the bowl of the rupture disk 1 first breaks due to its weak structure, forming a central fluid channel, and the wellbore above and below the bridge plug is connected.

[0068] Immediate production: After the rupture disk 1 breaks, the oil and gas flow directly into the production string through the central channel of the guide head 11 and the connecting cylinder 16, achieving production at the first time without waiting for the bridge plug to dissolve.

[0069] Degradation of soluble materials: Soluble components such as the outer rubber cylinder 7 and the bi-directional anchoring slip body 9 (such as magnesium-aluminum alloy-based materials) gradually dissolve in the wellbore fluid environment, and the dissolution period is 72 - 240 hours.

[0070] Full-bore restoration: After dissolution is complete, only the fragments of the rupture disk 1 remain (the porcelain material can be discharged by backflow), and the wellbore returns to the full-bore state, avoiding the blockage risk caused by the residue of traditional bridge plugs.

[0071] The embodiment of the present invention also provides a wellbore plugging method based on a rupture disk type fully soluble bi-directional anchoring plugging bridge plug, including the following steps:

[0072] Step 101: Lower the bridge plug to the designed position in the well through a cable or coiled tubing, and connect the push cylinder 2 with the setting tool.

[0073] Step 102: Apply hydraulic thrust through the setting tool to push the cone 5 to move forward along the mandrel 4, causing the block units of the bi-directional anchoring slip body 9 to expand outwards and embed into the casing wall to form bi-directional anchoring, and at the same time compress the outer rubber cylinder 7 and the inner rubber cylinder 12 of the guide head 11 to form a seal.

[0074] Specifically, the conical part of the cone 5 squeezes and divides the bi-directional anchoring slip body 9 into block units, so that the bi-directional serrated teeth thereof are embedded into the casing wall.

[0075] The depth of the slot between the block units is 70-85% of the wall thickness of the slip body, ensuring that the bi-directional pressure can be borne after anchoring.

[0076] The large outer diameter section of the cone 5 compresses the protection bowl 6 and the outer rubber cylinder 7, causing the outer rubber cylinder to expand radially to seal the casing annulus.

[0077] The small outer diameter section of the cone 5 is inserted into the inner cavity of the guide head 11 to form a metal-elastomer composite seal with an interference of 0.5-1.2 mm with the inner rubber cylinder 12.

[0078] Step 103: When the hydraulic pressure reaches the set value, the shear pin 10 breaks, causing the mandrel 4 to disengage from the guide head 11, completing the setting of the bridge plug.

[0079] Specifically, the fracture threshold of the shear pin 10 is set according to the shear force required to disengage from the push tube 2 after the bridge plug is set, and the calculation formula is: where d is the diameter of the shear pin 10, τ is the shear strength of the material, and n is the number of shear pins 10.

[0080] Step 104: After the wellhead pressure is relieved to a pressureless state, replace the wellhead and lower the production string.

[0081] Specifically, after the production string is lowered, the residual sealing pressure of the inner rubber cylinder 12 is detected through the matching structure of the stepped sealing groove in the inner cavity of the guide head 11 and the cup head screw 13.

[0082] When the detected pressure value is lower than 2 MPa, it is determined that the sealing function of the inner rubber cylinder 12 has failed.

[0083] Step 105: Apply pressure to the wellhead to 15-35 MPa to cause the rupture disc 1 to break and form a central fluid passage.

[0084] Specifically, the pressure application direction is to apply pressure from the bottom of the bowl of the rupture disc 1, and the directional rupture is realized by using the strength gradient of its bowl-shaped structure.

[0085] After rupture, the fragment size is smaller than the inner diameter of the central passage of the guide head 11 and is discharged to the ground with the fluid backflow.

[0086] Before applying pressure at the wellhead, inject sand-carrying fluid above the bridge plug, so that after the rupture disc 1 breaks, the sand grains temporarily block the passage of the guide head 11 to control the initial production flow rate not exceeding 120% of the design value.

[0087] Step 106: Realize the up-and-down connection of the wellbore through the said passage and put it into production immediately.

[0088] Step 107: After the soluble component of the bridge plug is dissolved, the full bore of the wellbore is restored.

[0089] Specifically, the soluble component includes an outer rubber cylinder 7 made of magnesium-aluminum alloy and a bi-directional anchoring slip body 9, which is completely dissolved within 72 - 240 hours in the wellbore fluid environment.

[0090] As described above, only the preferred embodiments of the present invention are given, and they are not used to limit the protection scope of the present invention.

Claims

1. A rupture disc type fully soluble bidirectional anchored plugging bridge plug, characterized in that: It includes a push cylinder, a push cylinder pressure cylinder, a core shaft, a cone, and a guide head assembly which are connected in sequence; Also included is a rupture disk disposed at a step inside the seeker assembly; The core shaft is inserted into the cone, one end of which is connected to the guide head assembly through a shear pin and faces the rupture disk, and the other end is connected to the push cylinder through a thread.

2. The rupture disc type fully soluble bidirectional anchoring plug according to claim 1 is characterized in that: The core shaft is provided with an annular shear groove, and the annular shear groove is combined with a shear pin. The shear strength of the shear pin is designed to be the shear force value required for the bridge plug to separate from the push cylinder after the sealing is completed.

3. The rupture disc type fully soluble bidirectional anchoring plugging bridge plug according to claim 1 or 2, characterized in that: It also includes a bidirectional anchoring slip body, which is divided into a plurality of block-shaped units that can be supported outwards by slots, and has a conical hole matched with the cone inside.

4. The rupture disc type fully soluble bidirectional anchoring plugging bridge plug according to claim 3 is characterized in that: The block units of the bidirectional anchoring slip body are provided with bidirectionally distributed teeth, the slot depth between adjacent block units is 70-85% of the wall thickness of the slip body, and the bidirectional anchoring slip body forms bidirectional anchoring with the casing wall through the bidirectionally distributed teeth.

5. The rupture disc type fully soluble bidirectional anchoring plugging bridge plug according to claim 4 is characterized in that: The guide head assembly includes a guide head and a connecting tube, through which the guide head and the bidirectional anchoring slip body are connected; the guide head is provided with a step, and the bowl-shaped buckle of the rupture disk is placed on the step to limit the axial movement of the rupture disk.

6. The rupture disc type fully soluble bidirectional anchoring plug according to claim 4 is characterized in that: It also includes an outer rubber tube and a protective bowl. The outer rubber tube and the protective bowl are sequentially sleeved on the large outer diameter section of the cone and positioned by a spacer ring.

7. The rupture disc type fully soluble bidirectional anchoring plug according to claim 5 is characterized in that: It also includes an inner rubber tube, which is fixed to the inner cavity of the connecting tube by a fixing screw and has an inner diameter smaller than the small outer diameter section of the cone.

8. The rupture disc type fully soluble bidirectional anchoring plug according to claim 7 is characterized in that: The rupture disk is in a bowl-shaped structure, the compressive strength of the bowl mouth is greater than that of the bowl bottom, and the critical rupture pressure is 15-35 MPa.

9. The rupture disc type fully soluble bidirectional anchoring plugging bridge plug according to claim 8, characterized in that: The inner cavity of the connecting tube is provided with a stepped sealing groove, and the end of the inner rubber tube is crimped and fixed in the stepped sealing groove by fixing screws.

10. A wellbore plugging method for a rupture disc type fully soluble bidirectional anchor plugging bridge plug according to any one of claims 1 to 9, characterized in that: The method is: The bridge plug is lowered into the designed position in the well through a cable or a coiled tubing, and the push tube is connected to the setting tool; Apply hydraulic thrust through the setting tool to push the cone forward along the core shaft, so that the block unit outer support of the bidirectional anchoring slip body is embedded in the casing wall to form a bidirectional anchor, and at the same time, the outer rubber tube and the inner rubber tube of the guide head are compressed to form a seal; When the hydraulic pressure reaches the set value, the shear pin breaks, causing the mandrel to separate from the guide head, completing the setting of the bridge plug; After the wellhead is depressurized to a pressure-free state, the wellhead is replaced and the production string is lowered; Pressurize the wellhead to 15-35MPa to break the rupture disk and form a central fluid channel; The wellbore is connected up and down through the channel and put into production immediately; After the soluble components of the bridge plug are dissolved, the full bore of the wellbore is restored.

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