A packer release structure and packer

Abstract

This invention provides a packer release structure and a packer. The packer release structure includes: a release block connected to the packer body via a release pin; a release section fitted inside the release block and coaxially connected to the self-compensating tubing, the release section having an assembly groove on its outer wall; a locking block disposed within the assembly groove for axially limiting the release block within the release section, the locking block having a shearing force greater than that of the release pin; and a support block disposed within the assembly groove for providing radial support to the locking block along the release section, the support block being heat-meltable, allowing the locking block to detach from the release block when the support block is heat-melted. Packers using this release structure can be run to deeper depths, and their heat-release mechanism does not cause structural damage to the self-compensating tubing.

Description

Technical Field

[0001] This invention relates to the field of oil production equipment technology, and in particular to a packer release structure and packer. Background Technology

[0002] Currently, the unsealing force between the self-compensating tubing and the packer body in conventional packers is generally controlled within 15 tons, mostly through shearing by shear pins or shear rings. During the unsealing process, excessive shearing force can cause deformation of the self-compensating tubing, which limits the current conventional packer insertion depth to within 500 meters, primarily in vertical well sections. However, current improvements in oil production technology mean that packers generally need to be inserted to depths of 1200-1500 meters or even deeper. At these depths, the shear pins or shear rings with conventional shearing forces are often insufficient in strength, easily causing the packer to automatically unseal. Increasing the strength (shearing force) of the shear pins or shear rings, on the other hand, can damage the structure of the self-compensating tubing during unsealing. Summary of the Invention

[0003] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a packer unsealing structure that is easy to unseal and is not limited to the depth of the well.

[0004] The second objective of this invention is to provide a packer that is resistant to high temperatures, has safe setting, and is easy to unseal.

[0005] The embodiments of the present invention are achieved through the following technical solutions:

[0006] A packer release structure includes: a release block connected to the packer body via a release pin; a release section fitted inside the release block and coaxially connected to a self-compensating tubing, the release section having an assembly groove on its outer wall; a locking block disposed within the assembly groove for axially limiting the release block within the release section, the locking block having a shearing force greater than that of the release pin; and a support block disposed within the assembly groove for providing radial support to the locking block along the release section, the support block being heat-meltable, and the locking block being able to detach from the release block when the support block is heat-melted.

[0007] According to a preferred embodiment, the card block is provided with outer unsealing ramps on both sides of the unsealing section along the axial direction, and the unsealing block is provided with inner unsealing ramps that cooperate with the outer unsealing ramps.

[0008] According to a preferred embodiment, the lower end of the unsealing block is provided with an unsealing connecting cap, which is sleeved on the outside of the unsealing block; the inner unsealing slope includes a first inner unsealing slope and a second inner unsealing slope; the second inner unsealing slope is disposed on the inner wall of the unsealing connecting cap, and the first inner unsealing slope is disposed at the lower end of the unsealing block; the first inner unsealing slope and the second inner unsealing slope define a groove in the axial direction of the unsealing section; the locking block can be embedded in the groove under the action of the support block.

[0009] According to a preferred embodiment, the unsealing block and the unsealing section are connected by a pre-installed pin; the shearing force of the pre-installed pin is less than the shearing force of the unsealing pin.

[0010] According to a preferred embodiment, the support block is made of a tin-bismuth alloy.

[0011] According to a preferred embodiment, the packer unsealing structure further includes a positioning block and a fixing key, wherein: the positioning block and the fixing key are both disposed in the assembly groove; in the axial direction of the unsealing section, the positioning block is located between the fixing key and the support block, one end of the positioning block abuts against the fixing key, and the other end abuts against the support block.

[0012] According to a preferred embodiment, a groove is provided on the outer side of the fixing key, and a clamp is provided on the outer sleeve of the unsealing section. The clamp is engaged in the groove to fix the fixing member into the assembly slot.

[0013] According to a preferred embodiment, the assembly groove includes an assembly cavity disposed within the side wall of the unsealing section. A limiting hole and an assembly hole, which communicate with each other, are disposed on the outer wall of the unsealing section, both connecting to the assembly cavity. The width of the limiting hole is less than the width of the assembly hole. A fixing plate is disposed on the locking block, the fixing plate being located within the assembly cavity, and the width of the fixing plate being greater than the width of the limiting hole. The locking block can protrude from the assembly cavity through the limiting hole. The width of the fixing plate is less than or equal to the width of the assembly hole. A fixing key is disposed at the assembly hole.

[0014] According to a preferred embodiment, the positioning block is provided with a limiting shoulder, the width of the positioning block and the width of the limiting shoulder are both less than or equal to the width of the assembly hole; the width of the positioning block and the width of the limiting shoulder are both greater than the width of the limiting hole; the limiting shoulder protrudes from the assembly cavity through the assembly hole.

[0015] A packer, including the aforementioned packer release structure, further includes: a self-compensating oil pipe; a main body sleeve, fitted over the self-compensating oil pipe and positioned near its upper end; an intermediate sleeve, fitted over the self-compensating oil pipe and positioned near its lower end; a central tube, fitted over the self-compensating oil pipe and positioned between the main body sleeve and the intermediate sleeve, one end of the central tube connected to the main body sleeve and the other end connected to the intermediate sleeve; a toothed ring pressure sleeve, fitted over the central tube; and a sealing sleeve seat, fitted over the central tube and abutting against the intermediate sleeve; and a sealing ring. A sealing cylinder, sleeved outside the central tube, is located between the toothed ring pressure sleeve and the sealing cylinder seat. One end of the sealing cylinder abuts against the toothed ring pressure sleeve, and the other end abuts against the sealing cylinder seat. The sealing cylinder is made of soft metal. A driving component, disposed between the main body cylinder and the central tube, is used to drive the toothed ring pressure sleeve to move toward the sealing cylinder seat to squeeze the sealing cylinder. The unsealing block is connected to the intermediate sleeve via an unsealing pin. A straightening sleeve is provided at the lower end of the intermediate sleeve, which abuts against the unsealing block to limit the unsealing block and prevent it from detaching from the intermediate sleeve axially upward and downward in the self-compensating oil pipe.

[0016] The technical solutions of the embodiments of the present invention have at least the following advantages and beneficial effects:

[0017] (1) The fixed structure of the support block and the locking block set by the present invention allows the user to increase the strength of the locking block synchronously according to the downhole depth of the self-compensating tubing or packer. When it is necessary to unseal, heat is injected downhole, and the temperature of the heat source can melt the support block. At this time, the locking block loses its radial support in the unsealing section, the support block retracts into the assembly groove, the fixation between the unsealing section and the unsealing block disappears, and the self-compensating tubing and the unsealing section can slide freely relative to the unsealing block. At this time, the self-compensating tubing is lifted and the unsealing pin is cut to achieve the unsealing of the packer. The unsealing section and the unsealing block are fixed by the structure of the support block and the locking block. During the unsealing process, the operation of cutting the traditional shear pin by lifting or lowering the self-compensating tubing is avoided. The strength of the locking block can be increased synchronously with the downhole depth of the packer. Therefore, the packer equipped with this unsealing structure can be lowered to a deeper depth downhole. With the design of increasing the strength of the locking block, the packer can be lowered into a deviated well, which increases the application range of the packer.

[0018] (2) After the packer of the present invention is lowered into the casing at a specified depth, the toothed ring pressure sleeve is driven by the driving component to move along the axial direction of the central tube toward the sealing cylinder seat. The sealing cylinder is made of soft metal material. With the continuous action of the driving component, the toothed ring pressure sleeve and the sealing cylinder seat squeeze the sealing cylinder, causing it to undergo plastic deformation and radial expansion deformation. When the sealing cylinder is deformed to fit tightly against the inner wall of the casing, the setting action of the packer can be completed. The sealing cylinder is made of soft metal material, which is resistant to high temperature and can meet the high temperature requirements of the heavy oil thermal recovery process, and can ensure good sealing performance. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the packer provided in an embodiment of the present invention;

[0021] Figure 2 for Figure 1 A partially enlarged schematic diagram of the structure at point A;

[0022] Figure 3 for Figure 1 A magnified view of the structure at point B in the middle;

[0023] Figure 4 for Figure 1 A magnified view of the structure at point C;

[0024] Figure 5 This is an exploded view of the structure of the unsealing section and the card block after assembly, as provided in an embodiment of the present invention.

[0025] Figure 6 for Figure 5 A magnified view of the structure at point D.

[0026] Icons: 1. Self-compensating oil pipe; 2. Main body; 3. Central tube; 4. Piston assembly; 5. Piston connecting sleeve; 51. Limiting step; 6. Ratchet push ring; 7. Ratchet ring; 8. Toothed ring pressure sleeve; 9. Sealing cylinder; 91. Conical cavity; 92. Deformation groove; 93. Sealing part; 94. Main body; 10. Sealing cylinder seat; 11. Upper cone; 12. Lower cone; 13. Slip sleeve; 14. Slip assembly; 15. Intermediate sleeve; 16. Locking claw; 17. Unsealing block; 171. First inner unsealing bevel; 18. Unsealing pin; 19. Pre-installed pin; 20. Straightening sleeve; 21. Unsealing short section; 22. 23. Third fixing pin; 24. Clamping sleeve; 25. Fourth fixing pin; 26. Second fixing pin; 27. First fixing pin; 28. Fixing key; 29. ​​Hoop groove; 20. Pressure oil hole; 31. Lower short section head; 32. Upper short section head; 33. Adapter pipe; 34. Unsealing connector cap; 35. Second inner unsealing slope; 36. Clamp; 37. Positioning block; 38. Limiting shoulder; 39. Support block; 30. Locking block; 39. Fixing base plate; 30. Outer unsealing slope; 31. Assembly groove; 32. Assembly cavity; 33. Limiting hole; 34. Assembly hole; 35. Clamping pin. Detailed Implementation

[0027] To better understand and implement this invention, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings.

[0028] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0030] Please refer to Figures 1 to 6A packer release structure includes a release block 17, a release section 21, a locking block 36, and a support block 35. The release block 17 is connected to the packer body via a release pin 18. The release section 21 is fitted inside the release block 17 and coaxially connected to a self-compensating oil pipe 1. An assembly groove 37 is formed on the outer wall of the release section 21. The locking block 36 is disposed within the assembly groove 37 and is used to axially limit the release block 17 within the release section 21. The shearing force of the locking block 36 is greater than the shearing force of the release pin 18. The support block 35 is disposed within the assembly groove 37 and is used to provide radial support for the locking block 36 along the release section 21. The support block 35 is heat-meltable; when the support block 35 is heat-melted, the locking block 36 can disengage from the release block 17. In this embodiment, the locking block 36 is used to axially limit the release of the release section 21 and the self-compensating tubing 1 assembled with it, so that the self-compensating tubing 1 and the release block 17 can maintain a fixed relative position during packer setting. The shearing force of the release pin 18 is less than 15 tons, on the premise that it will not damage the structure of the self-compensating tubing 1 when sheared. It should be noted that as the downhole depth increases, the length and weight of the self-compensating tubing 1 increase accordingly. Therefore, the strength (shearing force) of the fixing structure between the self-compensating tubing 1 and the release block 17 needs to be increased accordingly. Conventional shear pin fixing methods are prone to damaging the structure of the self-compensating tubing 1 during the release process (by lifting or pressing down the self-compensating tubing 1 to shear the shear pin).

[0031] In this embodiment, the fixing structure of the support block 35 and the locking block 36 allows the user to simultaneously increase the strength (shearing force) of the locking block 36 according to the downhole depth of the self-compensating tubing 1 or the packer. When unsealing is required, heat is injected downhole, and the temperature of the heat source can melt the support block 35. At this time, the locking block 36 loses radial support in the unsealing section 21, the support block 35 retracts into the assembly groove 37, the fixation between the unsealing section 21 and the unsealing block 17 disappears, and the self-compensating tubing 1 and the unsealing section 21 can slide freely relative to the unsealing block 17. At this time, the self-compensating tubing 1 is lifted, and the unsealing pin 18 is cut to achieve the unsealing of the packer. The structure secured by the combination of support block 35 and locking block 36 fixes the unsealing sub 21 and unsealing block 17, avoiding the need to shear the traditional shear pin (the traditional shear pin refers to the pin used to fix the self-compensating tubing 1 and unsealing block 17, unlike the unsealing pin 18, which requires much greater strength or shearing force when the well depth reaches 1200-1500 meters or even deeper) during the unsealing process. The strength of the locking block 36 can be adjusted according to the packer's position. As the downhole depth increases, the packer equipped with this unsealing structure can be driven to a deeper depth. With the increased strength of the clamping block 36, the packer can be driven into a deviated well (the deviated angle causes the stepped structure on the outer wall of the packer to collide and rub against the casing wall during the driving process, which can result in a shear force of 10-20 tons, potentially damaging the traditional shear pin). This increases the packer's application range and avoids damage to the self-compensating tubing 1 during the unsealing process.

[0032] Furthermore, such as Figures 4 to 6 As shown, the locking block 36 has outer unsealing ramps 362 on both sides of the unsealing section 21 along the axial direction, and the unsealing block 17 has an inner unsealing ramp that cooperates with the outer unsealing ramps 362. In this embodiment, the structure of the outer unsealing ramps 362 and the inner unsealing ramps allows the support block 35 to limit the unsealing block 17 along the axial direction of the unsealing section 21 before the support block 35 is heat-fused; and when the support block 35 is heat-fused, under the gravity of the self-compensating oil pipe 1 and the unsealing section 21, the outer unsealing ramps 362 and the inner unsealing ramps can slide relative to each other, and the inner unsealing ramps can apply a radial inward force to the locking block 36 along the unsealing section 21, so that the support block 35 can be smoothly retracted into the assembly groove 37, so that the unsealing section 21 can be separated from the unsealing block 17. Meanwhile, the locking block 36 is equipped with an outer unsealing inclined surface 362 on both sides of the unsealing section 21 in the axial direction. This design ensures that during the process of the unsealing section 21 sliding freely relative to the unsealing block 17 after unsealing, the locking block 36 will not be limited by other structures in the axial direction of the unsealing section 21, thus guaranteeing the free sliding of the unsealing section 21 relative to the unsealing block 17.

[0033] Specifically, such as Figure 4As shown, the lower end of the unsealing block 17 is provided with an unsealing connecting cap 32, which is sleeved on the outside of the unsealing block 17. The inner unsealing slope includes a first inner unsealing slope 171 and a second inner unsealing slope 321. The second inner unsealing slope 321 is disposed on the inner wall of the unsealing connecting cap 32, and the first inner unsealing slope 171 is disposed at the lower end of the unsealing block 17. The first inner unsealing slope 171 and the second inner unsealing slope 321 define a slot in the axial direction of the unsealing section 21. The locking block 36 can be embedded in the slot under the action of the support block 35. Here, the unsealing connecting cap 32 and the unsealing block 17 are threadedly connected. By adjusting the unsealing connecting cap 32 in the axial direction of the unsealing section 21 through threaded transmission, the distance between the first inner unsealing slope 171 and the second inner unsealing slope 321 can be adjusted, thereby adjusting the volume of the slot to accommodate locking blocks 36 of different specifications. To prevent the unsealing connector 32 from coming loose, a clamping pin 38 is threaded onto the unsealing connector 32, which can extend and abut against the outer wall of the unsealing block 17.

[0034] In this embodiment, the unsealing block 17 and the unsealing section 21 are connected by a pre-installed pin 19; the shearing force of the pre-installed pin 19 is less than that of the unsealing pin 18. The pre-installed pin 19 serves to pre-fix the unsealing block 17 and the unsealing section 21, facilitating assembly. During use, after the support block 35 is heat-fused, the pre-installed pin 19 is sheared, the locking block 36 retracts into the assembly groove 37, and the self-compensating oil pipe 1 and the unsealing section 21 can slide freely relative to the unsealing block 17. It should be noted that during use, the weight of the self-compensating oil pipe 1 and the unsealing section 21 is primarily pressed down on the locking block 36.

[0035] In this embodiment, the support block 35 may optionally be made of a tin-bismuth alloy. The steam temperature for downhole heating can reach approximately 350°C, which is sufficient to melt the tin-bismuth alloy support block 35. In other embodiments, the support block 35 may also be made of any alloy or material with a melting temperature between 100°C and 350°C.

[0036] In this embodiment, the packer unsealing structure further includes a positioning block 34 and a fixing key 27, wherein: both the positioning block 34 and the fixing key 27 are disposed within the assembly groove 37; in the axial direction of the unsealing section 21, the positioning block 34 is positioned between the fixing key 27 and the support block 35, with one end of the positioning block 34 abutting against the fixing key 27 and the other end abutting against the support block 35. Further, a groove 271 is provided on the outer surface of the fixing key 27, and a clamp 33 is fitted over the unsealing section 21, engaging within the groove 271 to fix the fastener to the assembly groove 37. Here, the positioning block 34 is used to position the support block 35 and the clamping block 36 axially within the assembly groove 37, and the fixing key 27 is used to cooperate with the positioning block 34 to fix the support block 35 and the clamping block 36 axially within the unsealing section 21. Figure 5 and Figure 6As shown, the fixing key 27 is fixed to the unsealing section 21 by the clamp 33.

[0037] Specifically, the assembly groove 37 includes an assembly cavity 371 disposed within the side wall of the unsealing section 21. The outer wall of the unsealing section 21 is provided with a limiting hole 372 and an assembly hole 373 that are interconnected. Both the limiting hole 372 and the assembly hole 373 are connected to the assembly cavity 371. The width of the limiting hole 372 is less than the width of the assembly hole 373. A fixing plate 361 is disposed on the locking block 36. The fixing plate 361 is located within the assembly cavity 371, and the width of the fixing plate 361 is greater than the width of the limiting hole 372. The locking block 36 can be exposed in the assembly cavity 371 through the limiting hole 372. The width of the fixing plate 361 is less than or equal to the width of the assembly hole 373. The fixing key 27 is disposed at the assembly hole 373. In use, firstly, the support block 35 is inserted into the assembly cavity 371 through the assembly hole 373, and then slid along the axial direction of the unsealing section 21 to the limiting hole 372; then, the locking block 36 is inserted into the assembly cavity 371 through the assembly hole 373, and then slid along the axial direction of the unsealing section 21 to the limiting hole 372, such that it is positioned above the support block 35 in the radial direction of the unsealing section 21, specifically, the fixing plate 361 is positioned above the support block 35. At this time, the locking block 36 passes through the limiting hole 372. The positioning hole 372 protrudes from the assembly cavity 371, allowing it to snap into the slot. Then, the positioning block 34 is inserted into the assembly cavity 371 through the assembly hole 373 and slides axially along the unsealing section 21 to the limiting hole 372, bringing it close to the locking block 36 and the support block 35. Finally, the fixing key 27 is inserted into the assembly cavity 371 through the assembly hole 373, abutting against the positioning block 34, and fixed to the unsealing section 21 by the clamp 33. This configuration prevents the locking block 36, positioning block 34, and fixing key 27 from detaching from the assembly slot 37 during the free sliding of the unsealing section 21 relative to the unsealing block 17 after the support block 35 has been heat-melted, ensuring operational safety. It should be noted that there is a certain gap between the locking block 36 and the fixing base plate 361 and the inner wall of the assembly cavity 371 or the side wall of the positioning block 34, to ensure that the locking block 36 can smoothly retract into the assembly cavity 371 after the support block 35 has been heat-melted.

[0038] In this embodiment, a limiting shoulder 341 is provided on the positioning block 34. The width of the positioning block 34 and the width of the limiting shoulder 341 are both less than or equal to the width of the assembly hole 373; the width of the positioning block 34 and the width of the limiting shoulder 341 are both greater than the width of the limiting hole 372; the limiting shoulder 341 protrudes from the assembly cavity 371 through the assembly hole 373. Here, the limiting shoulder 341 is used to cooperate with the boss at the connection between the assembly hole 373 and the limiting hole 372 to limit the positioning block 34 in the axial direction of the unsealing section 21, so as to prevent the positioning block 34 from pressing the locking block 36 in the axial direction of the unsealing section 21, ensuring the assembly space of the locking block 36, and facilitating the smooth retraction of the locking block 36 into the assembly cavity 371.

[0039] In this embodiment, optionally, multiple clamping blocks 36 are arranged at circumferential intervals along the unsealing section 21. Preferably, four clamping blocks 36 are arranged at circumferential intervals along the unsealing section 21. This can improve the structural strength after assembly.

[0040] like Figures 1 to 3 As shown, this embodiment also provides a packer, including the packer unsealing structure described above, and further including a self-compensating oil pipe 1, a main body cylinder 2, an intermediate sleeve 15, a central tube 3, a toothed ring pressure sleeve 8, a sealing cylinder seat 10, a sealing cylinder 9, and a driving component, wherein: the main body cylinder 2 is sleeved outside the self-compensating oil pipe 1 and is located near the upper end of the self-compensating oil pipe 1; the intermediate sleeve 15 is sleeved outside the self-compensating oil pipe 1 and is located near the lower end of the self-compensating oil pipe 1, and the intermediate sleeve 15 is connected to the self-compensating oil pipe 1; the central tube 3 is sleeved outside the self-compensating oil pipe 1 and is located between the main body cylinder 2 and the intermediate sleeve 15, one end of the central tube 3 is connected to the main body cylinder 2, and the other end is connected to the intermediate sleeve 15; the toothed ring pressure sleeve 8 is sleeved on the central tube 3. The outer sleeve 10 is fitted outside the central tube 3 and abuts against the intermediate sleeve 15; the sealing cylinder 9 is fitted outside the central tube 3 and is located between the toothed ring pressure sleeve 8 and the sealing sleeve 10. One end of the sealing cylinder 9 abuts against the toothed ring pressure sleeve 8 and the other end abuts against the sealing sleeve 10. The sealing cylinder 9 is made of soft metal material; the driving component is set between the main body cylinder 2 and the central tube 3 and is used to drive the toothed ring pressure sleeve 8 to move toward the sealing sleeve 10 to squeeze the sealing cylinder 9; the unsealing block 17 is connected to the intermediate sleeve 15 through the unsealing pin 18; the lower end of the intermediate sleeve 15 is provided with a straightening sleeve 20, which abuts against the unsealing block 17 and is used to limit the unsealing block 17 to prevent it from detaching from the intermediate sleeve 15 axially upward and downward in the self-compensating oil pipe 1.

[0041] Specifically, such as Figure 1 As shown, during use, after the packer is lowered into the casing at a specified depth, the toothed ring sleeve 8 is driven by the drive component to move along the axial direction of the central tube 3 toward the sealing cylinder seat 10. The sealing cylinder 9 is made of soft metal. With the continuous action of the drive component, the toothed ring sleeve 8 and the sealing cylinder seat 10 squeeze the sealing cylinder 9, causing it to undergo plastic deformation and radial expansion deformation. When the sealing cylinder 9 is deformed to fit tightly against the inner wall of the casing, the setting action of the packer can be completed.

[0042] In this embodiment, the sealing cylinder 9 of the packer is made of a soft metal material, which is resistant to high temperatures and can meet the high-temperature operating conditions required by the heavy oil thermal recovery process, ensuring excellent sealing performance. At the same time, it can also meet the requirements for use under normal temperature conditions.

[0043] In this embodiment, preferably, the sealing tube is made of copper.

[0044] To further improve the sealing performance between the inner wall of the sealing cylinder 9 and the outer wall of the central tube 3, a metal C-ring is installed between them. This packer is made of metal, enabling it to operate stably at 400℃ for extended periods without failure.

[0045] Furthermore, such as Figure 3 As shown, both ends of the sealing cylinder 9 are provided with conical cavities 91, and the toothed ring sleeve 8 and the sealing cylinder seat 10 are respectively embedded in the adjacent conical cavities 91. In this embodiment, both the toothed ring sleeve 8 and the sealing cylinder seat 10 are provided with conical protrusions at the ends near the sealing cylinder 9, and the conical protrusions are adapted to the conical cavities 91. The conical protrusions on the toothed ring sleeve 8 are embedded in the adjacent conical cavities 91, and the conical protrusions on the sealing cylinder seat 10 are embedded in the adjacent conical cavities 91. In use, as the conical protrusions extend into the conical cavities 91, the portion of the sealing cylinder 9 within the area of ​​the conical cavity 91 expands and deforms rapidly outward along the radial direction of the central tube 3, thereby achieving rapid sealing of the sleeve. The conical protrusion and the conical cavity 91 make it easier for the sealing cylinder 9 to undergo plastic deformation radially outward along the central tube 3 after being compressed, so that two sealing areas can quickly appear in the axial direction of the central tube 3, thereby improving the reliability of the sealing cylinder 9.

[0046] Furthermore, a deformation groove 92 is provided around the outer wall of the sealing cylinder 9, and this deformation groove 92 is located within the conical cavity 91 region in the axial direction of the sealing cylinder 9. In this embodiment, a deformation groove 92 is provided at both ends of the sealing cylinder 9. For ease of description, the area between the deformation groove 92 in the axial direction of the sealing cylinder 9 and the end adjacent to the deformation groove 92 is defined as the sealing part 93; the area between the two deformation grooves 92 is defined as the main body part 94. In this embodiment, the outer diameter of the sealing part 93 is larger than the outer diameter of the main body part 94. The design that the outer diameter of the sealing part 93 is larger than the outer diameter of the main body part 94 allows the outer wall of the sealing part 93 to better and faster fit against the inner wall of the sleeve during the deformation of the sealing cylinder 9. The deformation groove 92 facilitates the folding and deformation of the sealing part 93 relative to the main body part 94, avoiding the sealing failure between the inner wall of the sealing cylinder 9 and the outer wall of the central tube 3 caused by the deformation of the sealing part 93 affecting the main body part 94. In this embodiment, a metal C-ring is assembled within the region of the main body part 94.

[0047] In other embodiments, the number of deformation grooves 92 can be set as needed, and is not limited to one at each end of the sealing cylinder 9.

[0048] In this embodiment, the packer further includes an upper cone 11 and a lower cone 12 sleeved outside the central tube 3, with a retaining element 14 installed between the lower cone 12 and the upper cone 11; both the upper cone 11 and the lower cone 12 are embedded between the retaining element 14 and the central tube 3; the upper cone 11 is connected to the sealing sleeve 10, and the lower cone 12 is connected to the intermediate sleeve 15. In this embodiment, a retaining sleeve 13 is sleeved around the central tube 3, and the upper cone 11, the lower cone 12, and the retaining element 14 are all disposed between the retaining sleeve 13 and the central tube 3. A through hole is provided on the retaining sleeve 13. When the upper cone 11 and the lower cone 12 move towards each other, the retaining element 14 is exposed in the through hole under the action of the conical surfaces of the upper cone 11 and the lower cone 12, so that the retaining element abuts against the inner wall of the sleeve, thereby fixing the thermal recovery setter inside the sleeve. Specifically, as shown... Figure 1 As shown, the upper cone 11 is threadedly connected to the sealing sleeve 10, the lower cone 12 is threadedly connected to the intermediate sleeve 15, the sealing sleeve 10 is connected to the central tube 3 by the fourth fixing pin 24, and the upper cone 11 is connected to the slip sleeve 13 by the second fixing pin 25. During the setting process, the fourth fixing pin 24 and the second fixing pin 25 are sheared by the driving component. That is, the driving component drives the toothed ring pressure sleeve 8 to move towards the intermediate sleeve 15. The toothed ring pressure sleeve 8 drives the sealing sleeve 10 and the upper cone 11 to move synchronously through the sealing cylinder 9, so that the fourth fixing pin 24 and the second fixing pin 25 are sheared in sequence. At this time, the slip 14 unfolds under the compression of the upper cone 11 and the lower cone 12 and fits against the inner wall of the sleeve. At this time, the packer is fixed inside the sleeve. With the driving component, the sealing cylinder 9 deforms under the compression of the toothed ring pressure sleeve 8 and the sealing sleeve 10 to achieve setting.

[0049] Furthermore, a guide slot is provided on the slip sleeve 13 along the axial direction of the central tube 3, and a third fixing pin 22 is provided on the lower cone 12, which slides and nests within the guide slot. In use, before the second fixing pin 25 on the upper cone 11 is sheared off, the upper cone 11 and the slip sleeve 13 move downwards synchronously; after the second fixing pin 25 is sheared off, the third fixing pin 22 prevents the slip sleeve 13 from rotating circumferentially, ensuring that the slip piece 14 can be smoothly reset. In this embodiment, as... Figure 1As shown, a stepped cavity is provided at one end of the main body cylinder 2 near the intermediate sleeve 15, with the larger section of the stepped cavity located near the intermediate sleeve 15; the central tube 3 is threaded to the inner wall of the smaller section of the stepped cavity; the driving component is installed in the larger section. Further, the driving component includes a piston 4 and a piston connecting sleeve 5. One end of the piston connecting sleeve 5 is embedded in the larger section and abuts against the piston 4, while the other end is threaded to the toothed ring sleeve 8; the piston connecting sleeve 5 is connected to the main body cylinder 2 via a first fixing pin 26; the piston 4 is sealed against the inner wall of the larger section and the outer wall of the central tube 3; a pressure oil hole 28 is provided on the main body cylinder 2, which communicates with the larger section and is used to inject pressure oil into the larger section to drive the piston 4 towards the intermediate sleeve 15. In this embodiment, the pressure oil hole 28 is opened on the end face of the main body cylinder 2 and extends along the axial direction of the main body cylinder 2 to the large hole section of the stepped cavity. Specifically, the pressure oil hole 28 connects to the stepped surface at the junction of the large hole section and the small hole section.

[0050] To achieve a seal between the piston 4 and the outer wall of the central tube 3, as well as the inner wall of the large-hole section, metal C-rings are provided at both ends of the piston 4. The metal C-rings are fixed to the piston 4 by screwing C-ring fixing sleeves onto the ends of the piston 4. During use, pressurized oil is injected into the stepped cavity through the pressure oil port 28 via a hydraulic control line to drive the piston 4 towards the piston connecting sleeve 5 within the large-hole section. At this time, the first fixing pin 26 is sheared off. Subsequently, with the synchronous movement of the piston connecting sleeve 5 and the toothed ring pressure sleeve 8, the sealing cylinder seat 10 and the upper cone 11 are driven to move synchronously, causing the fourth fixing pin 24 and the second fixing pin 25 to be sheared off in sequence. This achieves the fixing of the thermal recovery separator by the slip 14 and the setting of the sealing cylinder 9. In this embodiment, if the sealing performance of the sealing cylinder 9 decreases during subsequent use, the piston 4 can continue to move toward the intermediate sleeve 15 by continuing to inject pressure oil into the pressure oil hole 28. This allows the sealing cylinder 9 to continue to be squeezed by the toothed ring pressure sleeve 8 and the sealing cylinder seat 10, thereby increasing its deformation and ensuring the sealing performance of the sealing cylinder 9.

[0051] Furthermore, such as Figure 2As shown, the outer wall of the central tube 3 is provided with ratchet teeth, and a ratchet ring 7 that engages with the ratchet teeth is fitted around the central tube 3. One end of the ratchet ring 7 abuts against the piston connecting sleeve 5, and the other end abuts against the toothed ring pressure sleeve 8. The ratchet teeth are inclined towards the middle sleeve 15. In this embodiment, a limiting step 51 is provided on the inner wall of the piston connecting sleeve 5, and a ratchet push ring 6 is provided between the limiting step 51 and the ratchet ring 7. The ratchet push ring 6 is fitted around the central tube 3. When the piston connecting sleeve 5 moves toward the intermediate sleeve 15 during use, the limiting step 51 pushes the ratchet push ring 6 and the ratchet ring 7 to move in the same direction, that is, downward. Under the action of the ratchet, the ratchet ring 7 can only move downward and cannot move upward. Therefore, the ratchet ring 7 that abuts against the toothed ring pressure sleeve 8 can ensure that the toothed ring pressure sleeve 8 does not move upward after squeezing the sealing cylinder 9. That is, the toothed ring pressure sleeve 8 achieves unidirectional limiting (cannot move upward) under the action of the ratchet ring 7, which can prevent the toothed ring pressure sleeve 8 from loosening during the setting process, and has high safety.

[0052] In this embodiment, as Figure 1 and Figure 4 As shown, a locking claw 16 is embedded in the intermediate sleeve 15, and the locking claw 16 is sleeved outside the self-compensating oil pipe 1. A release block 17 is slidably sleeved outside the self-compensating oil pipe 1. The release block 17 is connected to the intermediate sleeve 15 through a release pin 18, and the release block 17 is fixed to the self-compensating oil pipe 1 through a release section 21. The release block 17 is located at the claw hook part of the locking claw 16, and is located between the claw hook part and the self-compensating oil pipe 1, so that the claw hook part is hooked and connected to the inner wall of the intermediate sleeve 15. The upper end of the locking claw 16 is threaded to the central tube 3. In use, after the setting is completed and heat is injected, the support block 35 melts, and the locking block 36 loses its limiting effect on the release section 21 by the mating groove. At this time, the self-compensating oil pipe 1 can slide freely in the central tube 3, i.e., the release block 17, to facilitate the subsequent release action.

[0053] When unsealing is required, the self-compensating oil pipe 1 is lifted upwards, and the lower end of the unsealing section 21 abuts against the unsealing connecting cap 32. The self-compensating oil pipe 1 is lifted upwards, and the unsealing connecting cap 32 drives the unsealing block 17 upwards to cut the unsealing pin 18. The unsealing block 17 continues to move upwards and disengages from the claw hook of the locking claw 16. At this time, the claw hook disengages from the intermediate sleeve 15. The intermediate sleeve 15, lower cone 12, slip sleeve 13, slip 14, upper cone 11, sealing cylinder seat 10, and sealing cylinder 9 slide downwards along the outer wall of the central tube 3 under the action of gravity until the lower cone 12 abuts against the upper end of the locking claw 16. During this process, the slip 14 retracts into the slip sleeve 13 due to the disappearance of the squeezing action of the upper cone 11 and the lower cone 12, thus detaching from the inner wall of the casing. Similarly, the sealing cylinder 9 also loses the squeezing limit of the toothed ring pressure sleeve 8 and the sealing cylinder seat 10. Since it is made of soft metal, as the self-compensating oil pipe 1 continues to rise, the sealing part 93 will be squeezed and worn by the inner wall of the casing, thereby achieving unsealing and recycling of the packer.

[0054] In this embodiment, the upper end of the self-compensating oil pipe 1 is provided with an upper short joint 30, and a clamping sleeve 23 is provided on the outer sleeve of the self-compensating oil pipe 1. The clamping sleeve 23 is embedded in the main body cylinder 2 and is threadedly connected to the main body cylinder 2. The clamping sleeve 23 is located between the upper short joint 30 and the central pipe 3 in the axial direction of the self-compensating oil pipe 1. The self-compensating oil pipe 1 and the main body cylinder 2 are sealed with a metal C-ring, and this metal C-ring is located between the clamping sleeve 23 and the central pipe 3.

[0055] In this embodiment, the lower end of the unsealed short section 21 is fitted with a lower short section head 29 via an adapter pipe 31.

[0056] In summary, the working principle of this invention is as follows:

[0057] Setting: Pressurized oil is injected into the stepped cavity through the pressure oil hole 28, causing the piston 4 to drive the piston connecting sleeve 5 and the toothed ring pressure sleeve 8 to move downward synchronously. During this process, the first fixing pin 26 is sheared. Subsequently, the sealing cylinder 9 drives the sealing cylinder seat 10 and the upper cone 11 to move downward synchronously, and the fourth fixing pin 24 and the second fixing pin 25 are sheared in sequence. The slip 14 unfolds from the slip sleeve 13 under the compression of the upper cone 11 and the lower cone 12 and abuts against the inner wall of the sleeve to fix the packer in the sleeve. Finally, as the piston 4 moves further downward, the toothed ring pressure sleeve 8 cooperates with the sealing cylinder seat 10 to compress the sealing cylinder 9, deform it, and fit it tightly against the inner wall of the sleeve to achieve setting.

[0058] Heat injection: After the setting is completed, heat injection is performed, the support block 35 is melted, the locking block 36 is released from the unsealing block 17, the self-compensating oil pipe 1 expands due to heat and elongates axially, the pre-installed pin 19 is sheared, and the self-compensating oil pipe 1 can slide freely in the central pipe 3.

[0059] Unsealing: Lift the self-compensating oil pipe 1, and the lower end of the unsealing short section 21 abuts against the unsealing connecting cap 32. Continue to lift the self-compensating oil pipe 1 upward, and the unsealing connecting cap 32 drives the unsealing block 17 upward to cut the unsealing pin 18. The unsealing block 17 continues to move upward and disengages from the claw hook of the locking claw 16. At this time, the claw hook disengages from the intermediate sleeve 15. The intermediate sleeve 15, lower cone 12, slip sleeve 13, slip 14, upper cone 11, sealing cylinder seat 10, and sealing cylinder 9 slide downward along the outer wall of the central tube 3 under the action of gravity until the lower cone 12 abuts against the upper end of the locking claw 16. During this process, the slip 14 retracts into the slip sleeve 13 due to the disappearance of the squeezing action of the upper cone 11 and the lower cone 12, thus detaching from the inner wall of the casing. Similarly, the sealing cylinder 9 also loses the squeezing limit of the toothed ring pressure sleeve 8 and the sealing cylinder seat 10. As the self-compensating oil pipe 1 continues to rise, the sealing part 93 will be squeezed and worn by the inner wall of the casing, thereby achieving unsealing and recycling of the packer.

[0060] The technical means disclosed in this invention are not limited to those disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications are also considered within the scope of protection of this invention.

Claims

1. A de-encapsulation structure for a packer, characterized by, The application relates to a releasing structure of a packer, which comprises the following parts: a releasing block (17) connected to a packer body through a releasing pin (18); a releasing nipple (21) sleeved in the releasing block (17) and coaxially connected to a self-compensating oil pipe (1), an assembly groove (37) being formed in the outer wall of the releasing nipple (21); a clamping block (36) arranged in the assembly groove (37) and used for limiting the releasing block (17) in the axial direction of the releasing nipple (21), the shearing force of the clamping block (36) being greater than that of the releasing pin (18), outer releasing inclined surfaces (362) being arranged on the two sides of the clamping block (36) in the axial direction of the releasing nipple (21), and inner releasing inclined surfaces (362) being arranged on the releasing block (17) and matched with the outer releasing inclined surfaces (362); a supporting block (35) arranged in the assembly groove (37) and used for providing the clamping block (36) with a supporting force in the radial direction of the releasing nipple (21), the supporting block (35) being capable of being fused, the outer releasing inclined surfaces (362) and the inner releasing inclined surfaces being capable of sliding relative to each other under the action of gravity when the supporting block (35) is fused, the supporting block (35) being capable of being retracted into the assembly groove (37), and the clamping block (36) being capable of being separated from the releasing block (17); the releasing block (17) and the releasing nipple (21) are connected through a preloaded pin (19), and the shearing force of the preloaded pin (19) is smaller than that of the releasing pin (18). a releasing connecting cap (32) is arranged at the lower end of the releasing block (17) and sleeved on the releasing block (17); 2. The de-encapsulation structure for a packer of claim 1, wherein, the inner releasing inclined surfaces comprise a first inner releasing inclined surface (171) and a second inner releasing inclined surface (321); the second inner releasing inclined surface (321) is arranged on the inner wall of the releasing connecting cap (32), the first inner releasing inclined surface (171) is arranged at the lower end of the releasing block (17), and the first inner releasing inclined surface (171) and the second inner releasing inclined surface (321) define a clamping groove in the axial direction of the releasing nipple (21); the clamping block (36) can be embedded in the clamping groove under the action of the supporting block (35). the supporting block (35) is made of tin-bismuth alloy.

3. The de-encapsulating structure for a packer of claim 1, wherein, the releasing structure of the packer further comprises a positioning block (34) and a fixing key (27), wherein:

4. The de-encapsulation structure for a packer of claim 1, wherein, the positioning block (34) and the fixing key (27) are arranged in the assembly groove (37); in the axial direction of the releasing nipple (21), the positioning block (34) is located between the fixing key (27) and the supporting block (35), one end of the positioning block (34) abuts against the fixing key (27), and the other end abuts against the supporting block (35). a hoop groove (271) is arranged on the outer side surface of the fixing key (27), a clamping hoop (33) is sleeved on the releasing nipple (21), and the clamping hoop (33) is clamped in the hoop groove (271) so as to fix the fixing key in the assembly groove (37).

5. The de-encapsulation structure for a packer of claim 4, wherein, ​ 6. The de-encapsulation structure for a packer of claim 4, wherein, The assembling groove (37) comprises an assembling cavity (371) arranged in the sidewall of the unblocking nipple (21), and a limiting hole (372) and an assembling hole (373) are arranged in the outer wall of the unblocking nipple (21) and communicate with each other, and both the limiting hole (372) and the assembling hole (373) communicate with the assembling cavity (371); The width of the limiting hole (372) is smaller than the width of the assembling hole (373); The clamping block (36) is provided with a fixing seat plate (361), the fixing seat plate (361) is arranged in the assembling cavity (371), and the width of the fixing seat plate (361) is greater than the width of the limiting hole (372), and the clamping block (36) can be exposed to the assembling cavity (371) through the limiting hole (372); The width of the fixing seat plate (361) is smaller than or equal to the width of the assembling hole (373); The fixing key (27) is arranged at the assembling hole (373).

7. The de-encapsulation structure for a packer of claim 6, wherein, The positioning block (34) is provided with a limiting shoulder (341), and the width of the positioning block (34) and the width of the limiting shoulder (341) are both smaller than or equal to the width of the assembling hole (373); The width of the positioning block (34) and the width of the limiting shoulder (341) are both greater than the width of the limiting hole (372); The limiting shoulder (341) is exposed to the assembling cavity (371) through the assembling hole (373).

8. A packer, characterized by, The unblocking structure for the packer comprises the unblocking structure for the packer according to any one of claims 1-7, and further comprises: A self-compensating tubing (1); A main cylinder (2) is arranged outside the self-compensating tubing (1) and close to the upper end of the self-compensating tubing (1); An intermediate sleeve (15) is arranged outside the self-compensating tubing (1) and close to the lower end of the self-compensating tubing (1); A central pipe (3) is arranged outside the self-compensating tubing (1) and between the main cylinder (2) and the intermediate sleeve (15), one end of the central pipe (3) is connected to the main cylinder (2), and the other end is connected to the intermediate sleeve (15); A gear ring pressing sleeve (8) is arranged outside the central pipe (3); A cylinder seat (10) is arranged outside the central pipe (3) and abuts against the intermediate sleeve (15); A sealing cylinder (9) is arranged outside the central pipe (3) and between the gear ring pressing sleeve (8) and the cylinder seat (10), one end of the sealing cylinder (9) abuts against the gear ring pressing sleeve (8), and the other end abuts against the cylinder seat (10), and the sealing cylinder (9) is made of soft metal; and A driving member is arranged between the main cylinder (2) and the central pipe (3) and is used for driving the gear ring pressing sleeve (8) to move towards the cylinder seat (10) to press the sealing cylinder (9); The unblocking block (17) is connected to the intermediate sleeve (15) through an unblocking pin (18), and the lower end of the intermediate sleeve (15) is provided with a centralizing sleeve (20) which abuts against the unblocking block (17) and is used for limiting the unblocking block (17) to prevent it from being separated from the intermediate sleeve (15) in the axial direction of the self-compensating tubing (1).

Images