Hydraulic seat sealing, squeezing and plugging integrated removable bridge plug

Abstract

The utility model relates to the technical field of oil and gas field development downhole tools, in particular to a hydraulic seat sealing, squeezing and plugging integrated removable bridge plug. The mandrel is fixedly connected with the insertion pipe, the lower portion of the unsealing connector is fixed to the mandrel, a setting connector is fixed to the outer portion of the unsealing connector, the lower portion of the setting connector is connected with a slip anchoring mechanism, the sealing sleeve is sleeved with a sealing rubber cylinder in an anti-falling mode, and the slip anchoring mechanism abuts against the sealing rubber cylinder. The lower end of the sealing sleeve is fixedly connected with a plug, a switch sliding sleeve is sleeved with the sealing sleeve, a sliding sleeve mandrel is sleeved with the switch sliding sleeve, the sliding sleeve mandrel is fixedly connected with the lower end of the insertion pipe, and the plug, the sealing sleeve, the switch sliding sleeve and the sliding sleeve mandrel are respectively provided with an ash extrusion through hole to form an ash extrusion channel. The sliding sleeve mandrel is further provided with a liquid passing through hole, the liquid passing through hole is located below the control sliding sleeve, and the liquid passing through hole, the plug, the sealing sleeve and the ash extrusion through hole in the switch sliding sleeve jointly form a liquid flow channel. And delivery, well washing, seat sealing and extrusion plugging construction can be completed by tripping in a tubular column once, so that the construction efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of downhole tools technology for oil and gas field development, and in particular to a hydraulic seat-sealing-plugging integrated removable bridge plug. Background Technology

[0002] Currently, in oilfield development, to reduce the mutual influence between water-producing and sand-producing layers, it is necessary to seal the layers outside the production layers. Therefore, the layered plugging process is increasingly used. This involves using a bridge plug to protect the layer and the upper casing, then injecting the plugging agent into the well section that needs sealing or into formation fractures and pores to achieve the purpose of sealing and repairing leaks. Commonly used layered tools include mechanical integrated bridge plugs and hydraulic split bridge plugs. Mechanical integrated bridge plugs have a complex setting method and are not retrievable. Hydraulic split bridge plugs can be retrieved and recovered after the extrusion operation, but require multiple insertions of the tool to complete the plugging string, are more susceptible to wellbore interference, and have a long operation cycle.

[0003] Chinese utility model patent CN204646180U discloses a recyclable slurry squeezing bridge plug. During operation, a setting tool is used to lower the bridge plug into a predetermined position downhole. The setting tool is activated, and the setting connector is pushed downwards to cut the setting shear pin, causing the setting connector to move downwards and push the slip cone. The slip cone pushes the slip open and anchors it to the inner wall of the casing. The sealing sleeve is compressed and seals the annular space of the casing. At the same time, the locking ring of the bridge plug engages with the locking buckle on the locking sleeve, and the bridge plug self-locks. The external thread of the release connector is exposed on the top surface of the bridge plug. When the setting force exceeds the tensile limit of the annular groove on the mandrel, the mandrel is broken at the annular groove, and the bridge plug is set in the designed position downhole. The setting tool is then retrieved. Then, the insertion pipe is lowered to perform the slurry squeezing operation. After the operation is completed, the tubing string is lifted and the insertion pipe is pulled out. After the slurry solidifies, the bridge plug release tool is lowered to grasp the release connector of the bridge plug. The bridge plug release tool is then lifted to remove and recycle the bridge plug. This patent requires two runs of tubing to complete the plugging operation. During the process of retrieving the sealing tool and inserting the tubing, the bridge plug mandrel is exposed to the well fluid, and wellbore sediment may enter the bridge plug mandrel, causing the ash-squeezing tubing to fail to be inserted in place and the bridge plug injection channel to fail, resulting in construction failure.

[0004] Chinese invention patent CN103850663B discloses a removable seated and extruded integrated bridge plug, including a bridge plug setting mechanism, a tube, a mandrel, an unsealing connector, a setting connector, a slip anchoring mechanism, a bridge plug sealing mechanism, a locking mechanism, and a plug. The bridge plug setting mechanism includes an upper connector mandrel and a hydraulic cylinder pusher. The upper connector mandrel is threadedly connected to the upper part of the tube, and the lower end of the hydraulic cylinder pusher contacts the upper end of the setting connector, used to push the setting connector downwards during ball-throwing and pressure application. A sliding sleeve mandrel is threadedly connected to the lower part of the tube. A control sliding sleeve is fixed inside the sliding sleeve mandrel by sliding sleeve shear pins, temporarily sealing the extrusion hole on the sliding sleeve mandrel. The mandrel is sleeved outside the tube, and its upper end is threadedly connected to the tube. The unsealing connector is sleeved outside the tube and mandrel, and its lower part is fixed to the mandrel by unsealing shear pins. The setting connector is sleeved outside the unsealing connector and fixed to its upper part by setting shear pins. A slip anchoring mechanism is also included. The structure is fitted onto the mandrel and includes a slip cone, slip cylinder, slips, etc.; the bridge plug sealing mechanism is fitted onto the outside of the sealing sleeve and includes a sealing rubber sleeve and a spacer ring. The bottom surface of the slip cylinder contacts the upper end surface of the uppermost sealing rubber sleeve; the upper part of the sealing sleeve is threadedly connected to the lower part of the mandrel, and the lower end of the sealing sleeve extends into the plug and is threadedly connected to the plug. A switch sliding sleeve is provided in the annular space between the sealing sleeve and the sliding sleeve mandrel. A locking ring is threadedly connected to the lower part of the sliding sleeve mandrel; the locking mechanism includes a locking ring, a locking sleeve, and a locking block. The locking ring is located inside the seated joint and is threadedly connected to the seated joint. The locking sleeve is fitted onto the outside of the mandrel. The locking block is set in the locking block hole on the locking sleeve and extends inward into the locking block groove on the mandrel. The lower part of the release joint is fitted onto the outside of the locking sleeve to restrict the radial movement of the locking block. The locking block restricts the axial movement of the locking sleeve and the mandrel. The locking ring and the locking sleeve are provided with interlocking sawtooth threads. When the locking ring moves downward and engages with the threads of the locking sleeve, the bridge plug achieves self-locking.

[0005] This retrievable integrated seat-and-extract bridge plug has the insert pre-inserted into the plug's inner cavity. During use, the bridge plug is connected to the seat-and-extract tubing string and lowered to the designed downhole position. A ball is dropped, and pressure is applied to seat the bridge plug in the designed downhole position. Continued pressure application shears off the sliding sleeve shear pins, controlling the sliding sleeve to descend into the anti-reverse locking ring, opening the slurry extrusion hole on the sliding sleeve mandrel, thus connecting the slurry extrusion channel. At this point, a certain load is applied to perform the slurry extrusion operation. After the slurry extrusion operation is completed, the tubing string is lifted and the insert is pulled out. After the slurry solidifies, a bridge plug release tool is lowered to grasp the release joint of the bridge plug, and the release tool is lifted to remove and retrieve the bridge plug. This retrievable integrated seat-and-extract bridge plug only requires one tubing string run to complete the seating and plugging operation, shortening the operation cycle. However, in actual construction, after lowering the bridge plug to the designed downhole position, well washing is required before pressure setting to clean impurities from the tool to ensure the bridge plug's subsequent normal operation. Existing retrievable integrated seat-and-extract bridge plugs do not have a fluid flow channel, making well washing impossible. Utility Model Content

[0006] The purpose of this invention is to provide a hydraulically seated and squeezed integrated removable bridge plug to solve the problem that existing removable seated and squeezed integrated bridge plugs cannot be used for well washing before setting.

[0007] The present invention adopts the following technical solution:

[0008] A removable hydraulic seated and plugged integrated bridge plug includes an insert tube, an external release connector and a mandrel, the mandrel being fixedly connected to the insert tube. A groove is provided on the mandrel below its fixed connection point to form a weak structure. The lower part of the release connector is fixed to the mandrel by release shear pins. A seated connector is fixed externally to the release connector by seat shear pins. A slip anchoring mechanism is connected to the lower part of the seated connector, and the slip anchoring mechanism is sleeved on the outside of the mandrel. A sealing sleeve is fixedly fitted externally to the lower end of the mandrel. A sealing rubber sleeve is provided on the sealing sleeve to prevent detachment. The slip anchoring mechanism directly or intermittently presses against the sealing rubber sleeve. A space is provided between the seated connector and the mandrel. The locking mechanism enables the bridge plug to self-lock when the seated joint moves downward; a plug is fixedly connected to the lower end of the sealing sleeve, a switch sleeve is fitted inside the sealing sleeve, a sleeve mandrel is fitted inside the switch sleeve, and the sleeve mandrel is fixedly connected to the lower end of the insertion tube. The plug, sealing sleeve, switch sleeve, and sleeve mandrel are each provided with ash squeezing holes to form ash squeezing channels. A control sleeve is fixed inside the sleeve mandrel by a sleeve shear pin to temporarily block the ash squeezing holes on the sleeve mandrel. The sleeve mandrel is also provided with a liquid passage hole, which is located below the control sleeve. The liquid passage hole, together with the ash squeezing holes on the plug, sealing sleeve, and switch sleeve, forms a liquid flow channel.

[0009] Furthermore, after the sliding sleeve shear pin is cut off, the downward displacement of the sliding sleeve is controlled to be greater than the distance between the ash extrusion hole and the liquid passage hole on the sliding sleeve mandrel.

[0010] Furthermore, the liquid passage holes are provided in two or more locations and are evenly distributed at intervals on the same circumference.

[0011] Furthermore, a rubber sleeve seat is fitted onto the sealing sleeve, with the lower end face of the rubber sleeve seat contacting the sealing rubber sleeve. The slip anchoring mechanism presses against the rubber sleeve seat, thereby indirectly pressing against the sealing rubber sleeve.

[0012] Furthermore, the outer diameter of the rubber sleeve seat is larger than the outer diameter of the sealing rubber sleeve.

[0013] Furthermore, the bottom of the rubber sleeve seat has a ramp angle near its outer wall surface, and the ramp angle fits into the top conical surface of the sealing rubber sleeve.

[0014] Furthermore, the plug is provided with an anti-sticking layer on the outside, and the outer diameter of the anti-sticking layer is larger than the outer diameter of the sealing tube.

[0015] Furthermore, the mating surface between the locking mechanism and the upper end of the rubber sleeve seat is a stepped surface.

[0016] Furthermore, the hydraulic seated and plugged integrated removable bridge plug also includes a bridge plug seated mechanism. The bridge plug seated mechanism includes a central tube extending vertically and a hydraulic cylinder pusher sleeved outside the central tube. The upper part of the central tube is provided with a connecting structure for connecting the seated extrusion tube column, and the lower part of the central tube is fixedly connected to the insertion tube. A hydraulic cavity is formed between the hydraulic cylinder pusher sleeve and the central tube. The central tube is provided with a pressure transmission hole that communicates with the hydraulic cavity. The hydraulic cylinder pusher sleeve is in abutting contact with the upper end face of the seated joint.

[0017] Furthermore, the hydraulic cylinder pusher includes two or more piston cylinders, each piston cylinder forming a hydraulic chamber with the central tube. The central tube is provided with pressure transmission holes corresponding to each hydraulic chamber. The lower end of the last piston cylinder is connected to a pusher, which is in pressure contact with the upper end face of the seat seal joint.

[0018] Beneficial Effects: This utility model is an improved invention. Based on the existing removable integrated bridge plug structure, a fluid passage hole is added to the sliding sleeve mandrel. The fluid passage hole is located below the control sliding sleeve. The fluid passage hole, together with the plug, sealing sleeve, and the ash-squeezing passage hole on the switch sliding sleeve, forms a fluid flow channel. After the bridge plug is run into the well, before setting, well-washing fluid is injected into the casing. The well-washing fluid can enter the interior of the bridge plug through the fluid flow channel and return from the oil pipe connected above, realizing reverse well-washing operation. The deployment, well-washing, setting, and plugging construction can be completed in one run of tubing, greatly improving construction efficiency and saving operating costs. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the hydraulic seat sealing and plugging integrated removable bridge plug of this utility model;

[0020] Figure 2 for Figure 1 An enlarged schematic diagram of part A in the middle;

[0021] Figure 3 for Figure 1 Enlarged schematic diagram of part B in the middle;

[0022] In the diagram: 1. Upper connector; 2. Hydraulic cylinder pusher; 3. Sealing ring; 4. Pressure transmission hole; 5. Central tube; 6. Piston cylinder; 7. Pusher; 8. Insert tube; 9. Sealing shear pin; 10. Sealing connector; 11. Unsealing connector; 12. Mandrel; 13. Groove; 14. Unsealing shear pin; 15. Locking ring; 16. Locking block; 17. Locking sleeve; 18. Slip cone; 19. Limiting ring; 20. Slip; 21. Slip cylinder; 22. Sealing sleeve; 23. Rubber sleeve seat; 24. Inclined angle; 25. Sealing rubber sleeve; 26. Sliding sleeve mandrel; 27. Switch sliding sleeve; 28. Sliding sleeve shear pin; 29. ​​Control sliding sleeve; 30. Ash extrusion hole; 31. Liquid passage hole; 32. Plug; 33. Anti-stick layer; 34. Anti-reverse locking ring. Detailed Implementation

[0023] This invention provides a removable hydraulic seated and plugged integrated bridge plug, primarily addressing the problem that existing removable seated and plugged integrated bridge plugs cannot perform well-washing operations before setting. The basic inventive concept is to add a fluid passage hole to the sliding sleeve mandrel, forming a fluid flow channel together with the plug, sealing sleeve, and the ash-squeezing passage hole on the switch sliding sleeve. After the bridge plug is lowered into the well, well-washing fluid is injected into the casing before setting. The well-washing fluid can enter the interior of the bridge plug through the fluid flow channel and return from the connected tubing above, achieving a backwashing operation.

[0024] Based on the above inventive concept, the embodiments of this utility model are described in detail below.

[0025] like Figure 1 As shown, this utility model of a hydraulically seated and plugged removable bridge plug (hereinafter referred to as bridge plug) includes a bridge plug body and a bridge plug seat mechanism, which is connected to the upper part of the bridge plug body. The bridge plug seat mechanism includes a vertically extending central tube 5, with an upper connector 1 at the upper part of the central tube 5. The upper connector 1 is threadedly connected to the upper end of the central tube 5 and is used to connect to the seated extrusion tube column. A hydraulic cylinder pusher 2 is fitted outside the central tube 5, and the hydraulic cylinder pusher 2, upper connector 1, and central tube 5 are sealed by a sealing ring 3. A hydraulic cavity is formed between the hydraulic cylinder pusher 2 and the central tube 5, and a pressure transmission hole 4 communicating with the hydraulic cavity is provided on the central tube 5. Figure 2 As shown, the hydraulic cylinder pusher 2 includes multi-stage piston cylinders 6, each stage of the piston cylinder 6 forming a hydraulic chamber with the central tube 5. The central tube 5 has pressure transmission holes 4 corresponding to each hydraulic chamber. A pusher 7 is threadedly connected to the lower end of the final stage piston cylinder 6, and the lower end of the pusher 7 makes contact with the upper end face of the seat seal joint 10 of the bridge plug body. The lower end of the central tube 5 has an internal thread structure for threaded connection with the bridge plug body.

[0026] like Figure 3 As shown, the main body of the bridge plug includes an upper and lower extending tube 8. The upper end of the tube 8 extends into the central tube 5 and is threadedly connected to the central tube 5. A release connector 11 and a mandrel 12 are fitted around the outside of the tube 8. The release connector 11 has an external thread structure on its upper part for connecting a bridge plug release tool. The lower part of the release connector 11 is fixed to the mandrel 12 by a release shear pin 14. The upper end of the mandrel 12 is threadedly connected to the tube 8. A groove 13 with an outward opening is provided on the mandrel 12 below its threaded connection, forming a weak structure at the groove 13. When the sealing force exceeds the tensile strength limit of the groove 13, the mandrel 12 is broken at the groove 13, and the tube 8 separates from the mandrel 12. A setting connector 10 is fitted around the outside of the release connector 11, and the setting connector 10 is fixed to the release connector 11 by a setting shear pin 9.

[0027] The lower part of the sealing joint 10 is connected to a slip anchoring mechanism, which is sleeved on the outside of the mandrel 12. The slip anchoring mechanism includes a slip cone 18, a slip cylinder 21, a slip 20, and a limiting ring 19. The slip cone 18 and the slip cylinder 21 are sleeved on the mandrel 12. The upper part of the slip cone 18 extends into the sealing joint 10 and is threadedly connected to the sealing joint 10. The limiting ring 19 is sleeved on the outer circumference of the slip cone 18 and is threadedly connected to the upper part of the slip cylinder 21. The slip 20 is located in the slip 20 groove of the slip cylinder 21. The slip 20 and the slip cone 18 are slidably connected through a dovetail groove.

[0028] A sealing sleeve 22 is fitted onto the lower end of the mandrel 12. The sealing sleeve 22 is threadedly connected to the lower end of the mandrel 12, and a sealing ring is used to seal the mandrel 12. A slip sleeve 21 is fitted onto the mandrel 12. The sealing sleeve 22 is equipped with a bridge plug sealing mechanism to prevent detachment. The bridge plug sealing mechanism includes multiple sealing rubber sleeves 25, with spacers between adjacent sealing rubber sleeves 25. A rubber sleeve seat 23 is also fitted onto the sealing sleeve 22 above the sealing rubber sleeves 25. The lower end face of the rubber sleeve seat 23 contacts the uppermost sealing rubber sleeve 25. The slip sleeve 21 of the slip anchoring mechanism presses against the rubber sleeve seat 23, thereby indirectly pressing against the sealing rubber sleeve 25, preventing the slip sleeve 21 from directly contacting the sealing rubber sleeve 25 and causing wear on the sealing rubber sleeve 25, which would affect the sealing performance. The top-pressing mating surface of the slip sleeve 21 and the rubber sleeve seat 23 is a stepped surface. The stepped surface includes an upper horizontal surface, a lower horizontal surface, and a vertical surface connecting the two horizontal surfaces. The vertical surface of the stepped surface can limit the slip sleeve 21 and the rubber sleeve seat 23 in the circumferential direction, preventing the slip sleeve 21 and the rubber sleeve seat 23 from being misaligned relative to each other and affecting the transmission of the pushing force. This ensures that the rubber sleeve seat 23 is subjected to balanced force, thereby ensuring that the sealing rubber sleeve 25 is subjected to balanced pressure in all circumferential parts. After compression, the sealing rubber sleeve 25 has reliable sealing performance.

[0029] The lower outer diameter of the rubber sleeve seat 23 is larger than the outer diameter of the sealing rubber sleeve 25, so that the lower outer wall surface of the rubber sleeve seat 23 slightly exceeds the outer wall surface of the sealing rubber sleeve 25 in the radial direction. This can provide a certain shielding effect on the sealing rubber sleeve 25 from above, preventing the sealing rubber sleeve 25 from being compressed under pressure and prematurely set during the bridge plug's installation. The bottom of the rubber sleeve seat 23 has a ramp angle 24 near its outer wall surface. The ramp angle 24 has the same angle as the top conical surface of the sealing rubber sleeve 25 and fits against the top conical surface of the sealing rubber sleeve 25. By setting the ramp angle 24, the part of the bottom of the rubber sleeve seat 23 that protrudes from the outer wall surface of the sealing rubber sleeve 25 during the bridge plug's installation will not scrape against impurities on the inner wall of the casing. The lower end of the sealing sleeve 22 is threadedly connected to a plug 32. The plug 32 has an anti-adhesion layer 33 on its exterior. The outer diameter of the anti-adhesion layer 33 is larger than the outer diameter of the sealing sleeve 25, providing some protection to the sealing sleeve 25 from below. This, combined with the protection effect of the upper sleeve seat 23, prevents the sealing sleeve 25 from compressing under pressure and prematurely sealing during the bridge plug's lowering process. The anti-adhesion layer 33 is a rubber layer. After the cement removal operation, the rubber layer adheres to the cement. During bridge plug retrieval, the rubber layer detaches from the bridge plug, facilitating its removal.

[0030] A locking mechanism is provided between the seated joint 10 and the spindle 12 to achieve self-locking of the bridge plug when the seated joint 10 moves downward. The locking mechanism includes a locking ring 15, a locking sleeve 17, and a locking block 16. The locking ring 15 is threadedly connected inside the seated joint 10 and is positioned above the slip cone 18. The locking sleeve 17 is fitted over the spindle 12. The locking block 16 is located in the locking block hole on the locking sleeve 17 and extends inward into the locking block groove on the spindle 12. The locking sleeve 17 is positioned below the release joint 11, and the lower part of the release joint 11 is fitted over the locking sleeve 17 to stop the locking block 16 from the outside, restricting the radial movement of the locking block 16. The locking block 16 restricts the axial movement of the locking sleeve 17 and the spindle 12. The outer circumferential surface of the locking sleeve 17 and the inner circumferential surface of the locking ring 15 are provided with mutually engaging one-way latches. When the seated joint 10 moves downward a certain distance, the one-way latches on the locking ring 15 and the locking sleeve 17 engage with each other, achieving self-locking of the bridge plug.

[0031] A switch sleeve 27 is fitted inside the sealing sleeve 22. A sealing ring seals the inner circumferential surface of the switch sleeve 27 and the sealing sleeve 22. The lower end of the switch sleeve 27 extends into the plug 32. A sleeve mandrel 26 is fitted inside the switch sleeve 27. The upper part of the sleeve mandrel 26 is threadedly connected to the lower end of the insertion tube 8, and the lower end of the sleeve mandrel 26 extends into the plug 32. The plug 32, sealing sleeve 22, switch sleeve 27, and sleeve mandrel 26 are each provided with ash-squeezing holes 30 to form ash-squeezing channels. A control sleeve 29 is fixed inside the sleeve mandrel 26 by a sleeve shear pin 28, temporarily blocking the ash-squeezing holes 30 on the sleeve mandrel 26. The sleeve shear pin 28 passes through the ash-squeezing holes 30 on the sleeve mandrel 26 from the outside to the inside and is threaded into the threaded hole of the control sleeve 29. The top of the control sleeve 29 has a spherical surface for sealing with a steel ball. The sliding sleeve mandrel 26 is also provided with a liquid passage hole 31 connecting the inner cavity of the sliding sleeve mandrel 26 and the outside of the sliding sleeve mandrel 26. There are two or more liquid passage holes 31, which are evenly distributed on the same circumference to accelerate the flow rate of the well washing fluid. The liquid passage hole 31 is located below the control sliding sleeve 29. The liquid passage hole 31, together with the ash squeezing passage hole 30 on the plug 32, the sealing sleeve 22, and the switch sliding sleeve 27, form a liquid flow channel. The ash squeezing passage hole 30 on the plug 32, the sealing sleeve 22, and the switch sliding sleeve 27 acts as a slurry passage during ash squeezing operations and as a well washing fluid passage during well washing operations. It is not necessary to open a separate well washing fluid passage on the plug 32, the sealing sleeve 22, and the switch sliding sleeve 27, which simplifies the structure of the plug 32, the sealing sleeve 22, and the switch sliding sleeve 27.

[0032] The lower end of the sliding sleeve spindle 26 is threaded with a locking ring 34. The locking ring 34 and the control sliding sleeve 29 are provided with mutually cooperating one-way latches. When the sliding sleeve shear pin 28 is cut off, the control sliding sleeve 29 slides into the locking ring 34. The one-way latches on the control sliding sleeve 29 and the locking ring 34 engage with each other to form a lock, thereby limiting the control sliding sleeve 29.

[0033] After the shear pin 28 of the sliding sleeve is cut, the downward displacement of the sliding sleeve 29 is controlled to be greater than the distance between the mortar extrusion hole 30 and the liquid passage hole 31 on the sliding sleeve mandrel 26. After the sliding sleeve 29 slides down, it avoids the mortar extrusion hole 30 and the liquid passage hole 31 on the sliding sleeve mandrel 26. In this way, during the mortar extrusion operation, the liquid passage hole 31 on the sliding sleeve mandrel 26 can also act as a mortar passage, which is equivalent to forming two rings of mortar passage holes on the sliding sleeve mandrel 26, thus improving the efficiency of mortar extrusion construction. The mortar extrusion hole 30 on the sliding sleeve mandrel 26 is at the same height as the mortar extrusion hole 30 on the switch sliding sleeve 27, and the liquid passage hole 31 on the sliding sleeve mandrel 26 is at the same height as the mortar extrusion hole 30 on the sealing sleeve 22.

[0034] In use, the bridge plug is first lowered into the designed position in the well for well washing: well washing fluid is injected into the casing, and the well washing fluid enters the inner cavity of the bridge plug through the fluid flow channel and returns from the tubing, backwashing the bridge plug and tubing to clean impurities and ensure the bridge plug's normal operation afterwards. Then, setting is performed: a ball is dropped into the control sleeve 29, and pressure is applied. High-pressure liquid enters the hydraulic chamber from the pressure transmission hole 4, pushing the hydraulic cylinder pusher 2 downward, shearing the setting shear pin 9, and pushing the setting joint 10 and slip cone 18 downward. The slip cone 18 pushes the slip 20 to open and anchor on the inner wall of the casing, and the sealing sleeve 25 is compressed into the annular space of the sealing sleeve 22. At the same time, the locking ring 15 of the bridge plug engages with the one-way lock of the locking sleeve 17, and the bridge plug self-locks. When the setting force exceeds the tensile limit of the groove 13 on the mandrel 12, the mandrel 12 is broken at the groove 13, and the bridge plug is set in the designed position. Continue pressurizing until the pressure exceeds the shearing force of the sliding sleeve shear pin 28. The sliding sleeve shear pin 28 is then sheared, controlling the sliding sleeve 29 to slide down into the anti-reverse locking ring 34. The ash squeezing channel reopens, and the lowered tubing column is pressurized. Under the downward pressure of the insertion tube 8, the switch sliding sleeve 27 is ensured to be connected to the outer tube channel for the ash squeezing operation. After the operation is completed, the tubing column is lifted, and the switch sliding sleeve 27 moves upward with the insertion tube 8, closing the channel. The insertion tube 8 is then pulled out, and the mortar is allowed to solidify. After the mortar solidifies, the bridge plug unsealing tool is lowered to grasp the unsealing connector 11 of the bridge plug. The bridge plug unsealing tool is then lifted, activating the bridge plug unsealing mechanism. The unsealing shear pin 14 is sheared, the unsealing connector 11 moves upward, releasing the lock on the locking block 16. The slip 20 retracts, the sealing sleeve 25 retracts, and the bridge plug is unsealed. The bridge plug is then removed and recycled with the bridge plug unsealing tool.

[0035] This utility model features a hydraulically integrated retrievable bridge plug with stable performance, enabling integrated construction of bridge plug delivery, well washing, setting, and plugging. This shortens the operation cycle, saves operating costs, and allows for easy retrieval after plugging.

[0036] Of course, this utility model is not limited to the embodiments described above.

[0037] For example, in another embodiment, after the sliding sleeve shear pin is cut, the downward displacement of the controlled sliding sleeve can be equal to or less than the distance between the ash extrusion hole and the liquid passage hole on the sliding sleeve mandrel. In this way, after the controlled sliding sleeve slides down, the controlled sliding sleeve avoids the ash extrusion hole on the sliding sleeve mandrel, and the liquid passage hole on the sliding sleeve mandrel is blocked by the controlled sliding sleeve. The ash extrusion hole on the sliding sleeve mandrel, the switch sliding sleeve, the sealing sleeve, and the plug are connected, and the ash extrusion channel is reopened so that the ash extrusion operation can be carried out.

[0038] For example, in another embodiment, the number of liquid passage holes provided on the sliding sleeve mandrel can be flexibly selected as needed. All liquid passage holes can be evenly distributed on the same circumference, or they can be arranged at intervals in the circumferential direction without any requirement for the spacing. They can also be arranged in two circles.

[0039] For example, in another embodiment, the rubber sleeve seat can be omitted, and the lower end of the slip sleeve of the slip anchoring mechanism can be directly pressed against the sealing rubber sleeve, thus eliminating the need for the rubber sleeve seat and simplifying the bridge plug structure.

[0040] For example, in another embodiment, the outer diameter of the rubber sleeve holder can be equal to the outer diameter of the sealing rubber sleeve. In other embodiments, the bottom of the rubber sleeve holder is at a right angle near its outer wall surface.

[0041] For example, in another embodiment, the mating surface between the locking mechanism and the upper end of the rubber sleeve seat can also be a plane.

[0042] For example, in another embodiment, the lower end of the final-stage piston cylinder of the bridge plug sealing mechanism may not be connected to the push cylinder, allowing the final-stage piston cylinder to directly press against the upper surface of the sealing joint. The number of piston cylinder stages can be adjusted according to the sealing requirements; it can be a single-stage piston cylinder or two or more stages.

[0043] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. The patent protection scope of the present utility model shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present utility model shall also be included within the protection scope of the present utility model.

Claims

1. A hydraulically seated and plugged removable bridge plug, comprising an insert tube, an externally fitted release connector and a mandrel, the mandrel being fixedly connected to the insert tube, a groove being provided on the mandrel below its fixed connection point to form a weak structure, the lower part of the release connector being fixed to the mandrel by release shear pins, the external part of the release connector being fixed to a seated connector by seat shear pins, the lower part of the seated connector being connected to a slip anchoring mechanism, the slip anchoring mechanism being fitted outside the mandrel, the lower end of the mandrel being fixedly fitted with a sealing sleeve, the sealing sleeve having a sealing rubber sleeve for preventing detachment, and the slip anchoring... The mechanism directly or intermittently presses against the sealing sleeve. A locking mechanism is provided between the seated joint and the mandrel to achieve self-locking of the bridge plug when the seated joint moves downward. A plug is fixedly connected to the lower end of the sealing sleeve. A switch sleeve is fitted inside the sealing sleeve. A slide mandrel is fitted inside the switch sleeve. The slide mandrel is fixedly connected to the lower end of the insertion tube. The plug, sealing sleeve, switch sleeve, and slide mandrel are each provided with ash-squeezing holes to form ash-squeezing channels. A control sleeve is fixed inside the slide mandrel by a slide shear pin to temporarily block the ash-squeezing holes on the slide mandrel. Its characteristic is: The sliding sleeve spindle is also provided with a liquid passage hole, which is located below the control sliding sleeve. The liquid passage hole, together with the plug, the sealing sleeve and the ash-squeezing passage hole on the switch sliding sleeve, forms a liquid flow channel.

2. The hydraulic seat seal and plug integrated removable bridge plug according to claim 1, characterized in that: After the sliding sleeve shear pin is cut, the downward displacement of the sliding sleeve is controlled to be greater than the distance between the ash extrusion hole and the liquid passage hole on the sliding sleeve mandrel.

3. The hydraulic seat seal and plug integrated removable bridge plug according to claim 1, characterized in that: The liquid passage holes are provided in two or more locations and are evenly distributed on the same circumference.

4. The hydraulic seat seal and plug integrated removable bridge plug according to any one of claims 1-3, characterized in that: A rubber sleeve seat is fitted on the sealing sleeve, and the lower end face of the rubber sleeve seat contacts the sealing rubber sleeve. The slip anchoring mechanism presses against the rubber sleeve seat, thereby indirectly pressing against the sealing rubber sleeve.

5. The hydraulic seat seal and plug integrated removable bridge plug according to claim 4, characterized in that: The outer diameter of the rubber sleeve seat is larger than the outer diameter of the sealing rubber sleeve.

6. The hydraulic seat seal and plug integrated removable bridge plug according to claim 5, characterized in that: The bottom of the rubber sleeve seat has a ramp angle near its outer wall surface, and the ramp angle fits into the top conical surface of the sealing rubber sleeve.

7. The hydraulic seat seal and plug integrated removable bridge plug according to claim 5, characterized in that: The plug has an anti-sticking layer on the outside, and the outer diameter of the anti-sticking layer is larger than the outer diameter of the sealing tube.

8. The hydraulic seat seal and plug integrated removable bridge plug according to claim 4, characterized in that: The mating surface between the locking mechanism and the upper end of the rubber sleeve seat is a stepped surface.

9. The hydraulic seat seal and plug integrated removable bridge plug according to any one of claims 1-3, characterized in that: The hydraulic seated and plugged integrated removable bridge plug also includes a bridge plug seated mechanism. The bridge plug seated mechanism includes a central tube extending vertically and a hydraulic cylinder pusher sleeve fitted outside the central tube. The upper part of the central tube is provided with a connecting structure for connecting the seated extrusion column, and the lower part of the central tube is fixedly connected to the insertion tube. A hydraulic cavity is formed between the hydraulic cylinder pusher sleeve and the central tube. The central tube is provided with a pressure transmission hole that connects to the hydraulic cavity. The hydraulic cylinder pusher sleeve is in abutting contact with the upper end face of the seated joint.

10. The hydraulic seat seal and plug integrated removable bridge plug according to claim 9, characterized in that: The hydraulic cylinder pusher includes two or more piston cylinders. Each piston cylinder forms a hydraulic chamber with the central tube. The central tube is provided with pressure transmission holes corresponding to each hydraulic chamber. The lower end of the last piston cylinder is connected to a pusher, which is in pressure contact with the upper end face of the seat seal joint.

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