A double rubber sleeve layered packer capable of realizing effective seal checking and a working method thereof

Abstract

The application discloses a double rubber cylinder layered packer capable of effectively checking sealing and a working method thereof, and solves the technical problems of poor sealing checking precision and low sealing checking efficiency. The device comprises in sequence a coupling, an upper joint, a central pipe and a lower joint, the central pipe is provided with an upper rubber cylinder assembly located at a top end position of the central pipe, a lower rubber cylinder assembly located at a bottom end position of the central pipe, a sealing checking assembly located between the upper rubber cylinder assembly and the lower rubber cylinder assembly and used for checking sealing of an annular space between the upper rubber cylinder assembly and the lower rubber cylinder assembly, and a moving assembly used for pushing the upper rubber cylinder assembly and the lower rubber cylinder assembly to be respectively set on an inner wall of a casing. The application can improve the sealing checking precision, is convenient to operate, and can improve the sealing checking efficiency and operation efficiency.

Description

Technical Field

[0001] This invention belongs to the technical field of oil drilling, completion and production tools, specifically relating to a double-sleeve layered packer that can achieve effective sealing and its operation method. Background Technology

[0002] With the rapid development of oil drilling and production technology, the application of multi-layer casing tubing is becoming more and more widespread. At present, multi-layer casing tubing mainly uses layered packers to separate formations and producing layers, and is an important tool for achieving layered mining and layered fracturing.

[0003] Most existing layered packers are single-tube packers. Due to the tubing structure, the lower end of the layered packer is a perforation section. After the layered packer is set, a pressure test is required to verify the setting effect of the layered packer.

[0004] However, when using existing layered packers for sealing verification, the lower annulus of the packer is connected to the production formation. During pressure testing, the liquid medium can seep into the formation, making pressure stabilization impossible. Currently, the sealing condition is mainly judged indirectly by comparing pressure before and after setting and by annular return, which is prone to misjudgment and inaccurate verification. In addition, layered packers in offshore sand control tubing present challenges in field operation, with cumbersome procedures, poor timeliness, and single-layer operation time exceeding 3 hours, thus affecting sealing efficiency and requiring improvement. Summary of the Invention

[0005] In order to solve all or some of the above problems, the purpose of this invention is to provide a double-tube layered packer and its operation method that can achieve effective sealing, which can improve the sealing accuracy, ease of operation and sealing efficiency.

[0006] In a first aspect, the present invention provides a double-tube layered packer capable of effective sealing verification, comprising a coupling, an upper connector, a central tube, and a lower connector connected in sequence, wherein the central tube is provided with:

[0007] The glue applicator assembly is located at the top of the central tube;

[0008] The lower glue tube assembly is located at the bottom end of the central tube;

[0009] The sealing verification component is located between the upper glue tube assembly and the lower glue tube assembly, and is used to verify the sealing of the annulus between the upper glue tube assembly and the lower glue tube assembly;

[0010] A motion component is used to push the upper and lower rubber sleeve components to sit on the inner wall of the sleeve, respectively.

[0011] Optionally, the glue applicator assembly includes:

[0012] The upper adjusting ring is fixed to the bottom end of the upper connector;

[0013] The upper sleeve is slidably fitted onto the central tube. The upper end of the upper sleeve has a variable diameter, and the upper end of the upper sleeve forms an upper stepped surface. An upper ring groove is provided between the upper connector, the upper adjusting ring and the central tube. The top end of the upper sleeve is slidably engaged with the upper ring groove.

[0014] The upper rubber tube is sleeved on the upper sleeve, with the top end of the upper rubber tube abutting against the upper adjusting ring and the bottom end abutting against the upper stepped surface;

[0015] The motion component can push the upper sleeve upward, so that the upper rubber cylinder expands under the joint compression of the upper stepped surface and the upper adjusting ring, and sits and seals on the inner wall of the sleeve.

[0016] Optionally, the lower glue cartridge assembly includes:

[0017] The lower adjusting ring is fixed to the top of the lower connector;

[0018] The lower rubber sleeve is fitted onto the central tube, and the bottom end of the lower rubber sleeve abuts against the lower adjusting ring;

[0019] The motion component can apply a vertically downward compressive force to the lower rubber cylinder, causing the lower rubber cylinder to expand and sit on the inner wall of the sleeve.

[0020] Optionally, the motion component includes:

[0021] An upper liquid cylinder is slidably sleeved on the central tube. The top end of the upper liquid cylinder is connected to the upper sleeve, and an upper piston ring cavity is provided in front of the upper sleeve, the upper liquid cylinder and the central tube.

[0022] An upper piston is disposed within the upper piston ring cavity, and the top end of the upper piston abuts against the upper sleeve;

[0023] An upper pressure hole is formed on the central tube and communicates with the bottom end of the upper piston ring cavity;

[0024] The lower liquid cylinder is slidably sleeved on the central tube, and the top end of the lower liquid cylinder is connected to the upper liquid cylinder;

[0025] The lower piston is slidably sleeved on the central tube. The lower end of the lower piston has a reduced diameter, forming a lower step surface. The top end of the lower rubber sleeve abuts against the lower step surface. A lower ring groove is provided between the lower connector, the lower adjusting ring, and the central tube. The bottom end of the lower piston slides in the lower ring groove. A lower piston ring cavity is provided between the bottom end of the lower liquid cylinder and the central tube. The top end of the lower piston is located in the lower piston ring cavity and connected to the lower liquid cylinder.

[0026] The lower pressure hole is opened on the central tube and communicates with the top end of the lower piston ring cavity.

[0027] Optionally, the upper liquid cylinder and the upper sleeve are connected by a shear pin, and the shear pin can be sheared when the upper sleeve and the upper liquid cylinder move relative to each other.

[0028] Optionally, the inner wall of the upper cylinder is provided with a limit locking ring, and the outer wall of the upper piston is provided with a helical tooth structure that cooperates with the limit locking ring, so as to realize the anti-reverse capability of the upper and lower rubber cylinders.

[0029] Optionally, a sealing piston is tightly fitted onto the central tube, the outer wall of the sealing piston is tightly abutting against the inner wall of the lower cylinder, and a pair of limiting rings are fixedly connected to the central tube, with the pair of limiting rings abutting against both sides of the sealing piston.

[0030] Optionally, the lower piston has an assembly hole, the sealing assembly is disposed in the assembly hole, and the central tube has a sealing ring groove that communicates with the assembly hole. When the lower piston moves downward and the lower rubber sleeve is seated on the inner wall of the sleeve, and the top of the lower piston moves to the position of the sealing ring groove, the ring cavity of the lower piston communicates with the sealing ring groove.

[0031] Optionally, the seal verification component includes:

[0032] A support nut is threaded into the assembly hole;

[0033] A rupture disc is disposed at the bottom port of the supporting nut;

[0034] A sandproof cover is provided at the top port of the supporting nut;

[0035] A welding ring is fixed to the bottom end of the support nut.

[0036] Secondly, the present invention provides a method for operating a dual-tube layered packer, comprising the following steps:

[0037] S1, the packer is lowered into the casing, and the packer is pressurized by the ground pressurization equipment. Under the pressure, the moving component controls the upper rubber sleeve assembly and the lower rubber sleeve assembly to sit on the inner wall of the casing respectively.

[0038] S2, the packer is pressurized by ground pressurization equipment, and the sealing test assembly performs sealing test on the annulus between the upper and lower rubber sleeve assemblies.

[0039] As can be seen from the above technical solution, the double-tube layered packer and its operation method provided by the present invention, which can achieve effective sealing verification, have the following advantages:

[0040] This device utilizes a double-tube packer structure formed by the upper and lower tube assemblies, resulting in a better sealing performance than conventional single-tube layered packers. Furthermore, during sealing verification, the annulus between the two tube assemblies ensures no communication with the formation, leading to better pressure stabilization and more accurate sealing. Simultaneously, the device integrates setting and sealing verification, allowing for direct sealing verification from the current position after setting. The verification process eliminates the need for raising or lowering the tubing string, simplifying operation, reducing operational risks, and improving efficiency.

[0041] Other features and advantages of the present invention will be set forth in the following description. Attached Figure Description

[0042] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the technical solutions of the present invention, and do not constitute a limitation on the technical solutions of the present invention.

[0043] Figure 1 This is a schematic diagram of the overall structure of the double-tube layered packer in an embodiment of the present invention;

[0044] Figure 2 This is a cross-sectional view of the double-tube layered packer in an embodiment of the present invention;

[0045] Figure 3 This is a cross-sectional view of the double-tube layered packer in an embodiment of the present invention, showing the upper tube assembly;

[0046] Figure 4 This is a cross-sectional view of the dual-tube layered packer in an embodiment of the present invention, showing the lower tube assembly;

[0047] Figure 5 for Figure 4 Enlarged view of region A in the middle;

[0048] Figure 6 This is a cross-sectional view of the sealing verification component in an embodiment of the present invention.

[0049] Explanation of reference numerals in the attached figures:

[0050] 1. Coupling; 2. Upper connector; 3. Center tube; 4. Lower connector; 5. Upper rubber sleeve assembly; 51. Upper adjusting ring; 52. Upper sleeve; 53. Upper stepped surface; 54. Upper ring groove; 55. Upper rubber sleeve; 6. Lower rubber sleeve assembly; 61. Lower adjusting ring; 62. Lower rubber sleeve; 7. Inspection and sealing assembly; 71. Support nut; 72. Bursting disc; 73. Sandproof cover; 74. Welding ring; 8. Transportation Moving components; 81. Upper cylinder; 82. Shear pin; 83. Upper piston; 84. Lower cylinder; 85. Lower piston; 9. Upper piston ring cavity; 10. Fixing ring; 11. Upper pressure hole; 12. Lower step surface; 13. Lower ring groove; 14. Lower piston ring cavity; 15. Sealing piston; 16. Limiting ring; 17. Lower pressure hole; 18. Limiting locking ring; 19. Assembly hole; 20. Inspection sealing ring groove. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be arbitrarily combined with each other.

[0052] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 The figure shown is an embodiment of the present invention. This embodiment discloses a double-tube layered packer that can achieve effective sealing verification. It includes a coupling 1, an upper connector 2, a central tube 3 and a lower connector 4 connected sequentially from the upper right to the lower left. The coupling 1 is threadedly connected to the upper connector 2, and the lower connector 4 and the upper connector 2 are respectively connected to the central tube 3 by fastening screws.

[0053] In one embodiment, such as Figure 1 , Figure 2 As shown, the central tube 3 is equipped with an upper glue tube assembly 5, a lower glue tube assembly 6, a sealing inspection assembly 7, and a motion assembly 8. The upper glue tube assembly 5 is located at the top of the central tube 3, the lower glue tube assembly 6 is located at the bottom of the central tube 3, and the sealing inspection assembly 7 is located between the upper glue tube assembly 5 and the lower glue tube assembly 6.

[0054] After the pressure is applied to the central tube 3 by the pressure testing equipment, the motion component 8 is used to push the upper rubber sleeve assembly 5 and the lower rubber sleeve assembly 6 of the sleeve to sit and seal on the inner wall of the sleeve, respectively. As the pressure testing equipment continues to apply pressure, the sealing verification component 7 is used to verify the seal of the annulus between the upper rubber sleeve assembly 5 and the lower rubber sleeve assembly 6.

[0055] The dual-tube layered packer in this embodiment, which enables effective sealing, has a better sealing effect than conventional single-tube layered packers due to the dual-tube structure formed by the upper tube assembly 5 and the lower tube assembly 6. Furthermore, during the sealing operation, the sealing is performed in the annular space between the two tube assemblies, without communication with the formation, resulting in better pressure stabilization and more accurate sealing.

[0056] In one embodiment, such as Figure 2 , Figure 3 As shown, the glue-applying sleeve assembly 5 includes an upper adjusting ring 51 sleeved on the central tube 3, and the upper adjusting ring 51 is fixed to the bottom end of the upper connector 2 by screws. An upper sleeve 52 is slidably sleeved on the central tube 3. The upper end of the upper sleeve 52 has a variable diameter, and the outer diameter of the upper end of the upper sleeve 52 is smaller than the outer diameter of its lower end, so that the upper end of the upper sleeve 52 forms an upper stepped surface 53.

[0057] In one embodiment, such as Figure 2 , Figure 3 As shown, an upper ring groove 54 is provided between the upper connector 2, the upper adjusting ring 51, and the central tube 3, and the top end of the upper sleeve 52 slides into the upper ring groove 54. An elastic upper rubber sleeve 55 is fitted onto the upper end of the upper sleeve 52, with the top end of the upper rubber sleeve 55 abutting against the upper adjusting ring 51 and the bottom end abutting against the upper stepped surface 53. The moving component 8 can push the upper sleeve 52 upward, so that the upper rubber sleeve 55 expands under the joint compression of the upper stepped surface 53 and the upper adjusting ring 51, and sits sealed on the inner wall of the sleeve.

[0058] In one embodiment, such as Figure 2 , Figure 4 As shown, the lower rubber sleeve assembly 6 includes a lower adjusting ring 61 sleeved on the central tube 3, and the lower adjusting ring 61 is fixed to the top of the lower connector 4 by screws. An elastic lower rubber sleeve 62 is sleeved on the central tube 3, the bottom end of the lower rubber sleeve 62 abuts against the lower adjusting ring 61, and the moving component 8 can apply a vertically downward squeezing force to the lower rubber sleeve 62 to cause the lower rubber sleeve 62 to expand and sit on the inner wall of the sleeve.

[0059] In one embodiment, such as Figure 3 , Figure 4 As shown, the motion assembly 8 includes an upper cylinder 81 slidably sleeved on the central tube 3. The top end of the upper cylinder 81 is connected to the upper sleeve 52 via a shear pin 82. An upper piston ring cavity 9 is provided between the upper sleeve 52, the upper cylinder 81, and the central tube 3. An upper piston 83 is provided in the upper piston ring cavity 9, and the upper piston 83 is slidably sleeved on the central tube 3. At the same time, the top end of the upper piston 83 abuts against the upper sleeve 52, so that the upper piston 83 can drive the upper sleeve 52 to move upward.

[0060] In one embodiment, such as Figure 3 , Figure 4 As shown, a fixing ring 10 is fixedly sleeved on the central tube 3, located inside the upper piston ring cavity 9. The fixing ring 10 abuts against the bottom end of the upper piston 83 to limit the movement of the upper piston 83. Multiple upper pressure holes 11 are provided on the central tube 3, evenly distributed along the circumference of the central tube 3. These holes extend to the fixing ring 10 and simultaneously communicate with the bottom end of the upper piston ring cavity 9.

[0061] In one embodiment, such as Figure 3 , Figure 4 As shown, a lower liquid cylinder 84 is slidably sleeved on the central tube 3, and the top end of the lower liquid cylinder 84 is fixedly connected to the upper liquid cylinder 81 by screws. A lower piston 85 is slidably sleeved on the central tube 3. The lower end of the lower piston 85 has a variable diameter, and the outer diameter of the upper end of the lower piston 85 is larger than the outer diameter of its lower end, so that the lower end of the lower piston 85 forms a lower step surface 12. The top end of the lower rubber sleeve 62 abuts against the lower step surface 12, and the bottom end abuts against the lower adjusting ring 61.

[0062] In one embodiment, such as Figure 3 , Figure 4 As shown, a lower ring groove 13 is provided between the lower connector 4, the lower adjusting ring 61, and the central tube 3, and the bottom end of the lower piston 85 slides in the lower ring groove 13. At the same time, a lower piston ring cavity 14 is provided between the bottom end of the lower liquid cylinder 84 and the central tube 3, and the top end of the lower piston 85 is located in the lower piston ring cavity 14 and is fixedly connected to the lower liquid cylinder 84 by screws.

[0063] In one embodiment, such as Figure 3 , Figure 4 As shown, a sealing piston 15 is tightly fitted on the central tube 3. The outer wall of the sealing piston 15 is in close contact with the inner wall of the lower liquid cylinder 84. At the same time, a pair of limiting rings 16 are fixedly connected to the central tube 3, and the pair of limiting rings 16 abut against both sides of the sealing piston 15 to limit the sealing piston 15.

[0064] In one embodiment, such as Figure 3 , Figure 4 As shown, the central tube 3 is provided with a plurality of downward pressure holes 17, which are evenly distributed along the circumference of the central tube 3, and the plurality of downward pressure holes 17 are respectively connected to the top end of the lower piston ring cavity 14.

[0065] After the pressure is applied to the central tube 3 by the pressure testing equipment, the liquid medium enters the upper piston ring cavity 9 and the lower piston ring cavity 14 through the upper pressure hole 11 and the lower pressure hole 17. Under the pressure, the upper piston 83 drives the upper sleeve 52 to move upward, and the lower piston 85 drives the lower liquid cylinder 84 and the upper liquid cylinder 81 to move downward. At this time, the upper sleeve 52 and the upper liquid cylinder 81 move relative to each other and cut the shear pin 82. At this time, the upper rubber sleeve 55 and the lower rubber sleeve 62 are subjected to extrusion force and expand to seal against the inner wall of the sleeve.

[0066] In one embodiment, such as Figure 2 , Figure 3 As shown, the inner wall of the upper cylinder 81 is fixedly connected to a limit locking ring 18 by screws. The outer wall of the upper piston 83 is provided with a helical tooth structure that cooperates with the limit locking ring 18. When the upper piston 83 moves relative to the upper cylinder 81, the limit locking ring 18 cooperates with the helical tooth structure to limit the upper piston 83 and the upper cylinder 81, preventing the upper rubber sleeve 55 and the lower rubber sleeve 62 from resetting due to their own elasticity. In other words, it achieves the anti-reverse capability of the upper rubber sleeve 55 and the lower rubber sleeve 62.

[0067] In one embodiment, such as Figure 4 , Figure 5 As shown, the lower piston 85 has an assembly hole 19, and the sealing assembly 7 is disposed in the assembly hole 19. The outer wall of the central tube 3 has a sealing ring groove 20 that communicates with the assembly hole 19. When the lower piston 85 moves downwards and the lower rubber sleeve 62 is seated on the inner wall of the sleeve, and the top of the lower piston 85 moves to the position of the sealing ring groove 20, the ring cavity of the lower piston 85 communicates with the sealing ring groove 20. That is, from the moment the lower piston 85 begins to move downwards until the lower rubber sleeve 62 is seated, the ring cavity 14 of the lower piston is not connected to the sealing ring groove 20, and the sealing assembly 7 does not bear pressure during this time.

[0068] In one embodiment, such as Figure 5 , Figure 6 As shown, the sealing assembly 7 includes a support nut 71 threaded into the assembly hole 19. A rupture disc 72 is provided at the bottom port of the support nut 71, and a sand-proof cover 73 is provided at the top port to prevent formation sand from entering the stratified packer and affecting subsequent operations. At the same time, a welding ring 74 is fixedly connected to the bottom end of the support nut 71.

[0069] Pressure is applied to the central tube 3 using a pressure-pressuring device, causing the upper rubber sleeve 55 and the lower rubber sleeve 62 to be seated and sealed on the inner wall of the casing. At this time, the rupture disc 72 is not under pressure. As the pressure-pressuring device continues to pressurize and break the rupture disc 72, the sealing verification channel is opened. Subsequently, the pressure is increased to the sealing verification pressure by the pressure-pressuring device, and the sealing verification operation can begin.

[0070] As can be seen from the above process, this device features a double-tube structure, which provides a better sealing effect than conventional single-tube layered packers. During the sealing verification operation, the sealing is performed in the annular space between the two tubes, without communication with the formation, resulting in better pressure stabilization and more accurate sealing verification. Simultaneously, by incorporating a sand-proof cover 73, if the lower tube assembly 6 fails and formation sand enters between the two tubes, the sand-proof cover 73 can prevent formation sand from entering the layered packer and affecting subsequent operations, thereby improving the reliability of the seal. Furthermore, this design enables integrated setting and sealing verification. After setting, sealing can be directly verified at the current position without the need to raise or lower the tubing string during the verification process, simplifying operation, reducing operational risks, and improving operational efficiency.

[0071] This embodiment also discloses a method for operating a double-tube layered packer, including the following steps:

[0072] S1, the packer connecting string is lowered into the casing. At this time, the shear pin 82 at the upper cylinder 81 is not sheared, and none of the components move. The upper rubber sleeve assembly 5 and the lower rubber sleeve assembly 6 are not compressed. After the packer is lowered into place, pressure is applied from the central tube 3 through the pressure testing equipment. The pressure is transmitted from the upper pressure testing hole 11 and the lower pressure testing hole 17 to the upper piston 83 and the lower piston 85.

[0073] Under pressure, the upper piston 83 moves upward, and the upper rubber sleeve 55 is compressed and expanded until it fits against the inner wall of the sleeve. The lower piston 85 moves downward, and the lower rubber sleeve 62 is compressed and expanded until it fits against the inner wall of the sleeve. During the relative movement of the upper piston 83 and the lower piston 85, the limiting locking ring 18 moves with the upper liquid cylinder 81. After the setting is completed, the limiting locking ring 18 cooperates with the helical tooth structure to form a lock. At the same time, when the top of the lower piston 85 moves to the position of the sealing ring groove 20, it connects the ring cavity of the lower piston 85 with the sealing ring groove 20.

[0074] S2, continue pressurizing from the central tube 3 using the pressurizing equipment to break the rupture disc 72, opening the seal verification channel. Then pressurize to the seal verification pressure to begin the seal verification operation. If the annular pressure between the upper rubber sleeve 55 and the lower rubber sleeve 62 remains unchanged within the predetermined time, it proves that the setting seal is good; otherwise, it indicates that there is a problem with the setting seal.

[0075] It should be noted that, unless otherwise stated, the technical or scientific terms used in this invention should have the ordinary meaning as understood by one of ordinary skill in the art.

[0076] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly defined.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A double-tube layered packer capable of effective sealing verification, comprising a coupling (1), an upper connector (2), a central tube (3), and a lower connector (4) connected in sequence, characterized in that, The central tube (3) is provided with: The glue applicator assembly (5) is located at the top of the central tube (3); The lower rubber tube assembly (6) is located at the bottom end of the central tube (3); The sealing verification component (7) is located between the upper glue tube assembly (5) and the lower glue tube assembly (6) and is used to verify the sealing of the annulus between the upper glue tube assembly (5) and the lower glue tube assembly (6); Motion component (8) is used to push the upper rubber tube assembly (5) and the lower rubber tube assembly (6) to sit on the inner wall of the sleeve respectively; The glue applicator assembly (5) includes: The upper adjusting ring (51) is fixed to the bottom end of the upper connector (2); The upper sleeve (52) is slidably sleeved on the central tube (3). The upper end of the upper sleeve (52) has a variable diameter, and the upper end of the upper sleeve (52) forms an upper stepped surface (53). An upper ring groove (54) is provided between the upper connector (2), the upper adjusting ring (51) and the central tube (3). The top end of the upper sleeve (52) is slidably engaged with the upper ring groove (54). The upper rubber tube (55) is sleeved on the upper sleeve (52). The top end of the upper rubber tube (55) abuts against the upper adjusting ring (51) and the bottom end abuts against the upper stepped surface (53). The motion component (8) can push the upper sleeve (52) upward so that the upper rubber cylinder (55) expands under the joint compression of the upper step surface (53) and the upper adjusting ring (51) and sits on the inner wall of the sleeve; The lower glue cartridge assembly (6) includes: The lower adjusting ring (61) is fixed to the top of the lower connector (4); The lower rubber tube (62) is sleeved on the central tube (3), and the bottom end of the lower rubber tube (62) abuts against the lower adjusting ring (61); The motion component (8) can apply a vertically downward compressive force to the lower rubber cylinder (62) to cause the lower rubber cylinder (62) to expand and sit on the inner wall of the sleeve; The motion component (8) includes: The upper liquid cylinder (81) is slidably sleeved on the central tube (3). The top end of the upper liquid cylinder (81) is connected to the upper sleeve (52), and an upper piston ring cavity (9) is provided between the upper sleeve (52), the upper liquid cylinder (81) and the central tube (3). An upper piston (83) is disposed in the upper piston ring cavity (9), and the top end of the upper piston (83) abuts against the upper sleeve (52); The upper pressure hole (11) is opened on the central tube (3) and is connected to the bottom end of the upper piston ring cavity (9); The lower liquid cylinder (84) is slidably sleeved on the central tube (3), and the top end of the lower liquid cylinder (84) is connected to the upper liquid cylinder (81); The lower piston (85) is slidably sleeved on the central tube (3). The lower end of the lower piston (85) has a reduced diameter, and the lower end of the lower piston (85) forms a lower step surface (12). The top end of the lower rubber sleeve (62) abuts against the lower step surface (12). A lower ring groove (13) is provided between the lower connector (4), the lower adjusting ring (61) and the central tube (3). The bottom end of the lower piston (85) slides in cooperation with the lower ring groove (13). A lower piston ring cavity (14) is provided between the bottom end of the lower liquid cylinder (84) and the central tube (3). The top end of the lower piston (85) is located in the lower piston ring cavity (14) and connected to the lower liquid cylinder (84). The lower pressure hole (17) is opened on the central tube (3) and communicates with the top end of the lower piston ring cavity (14).

2. The double-tube layered packer according to claim 1, characterized in that, The upper cylinder (81) and the upper sleeve (52) are connected by a shear pin (82). When the upper sleeve (52) and the upper cylinder (81) move relative to each other, the shear pin (82) can be sheared.

3. The double-tube layered packer according to claim 1, characterized in that, The inner wall of the upper cylinder (81) is provided with a limiting lock ring (18), and the outer wall of the upper piston (83) is provided with a helical tooth structure that cooperates with the limiting lock ring (18) to realize the anti-reverse capability of the upper rubber cylinder (55) and the lower rubber cylinder (62).

4. The double-tube layered packer according to claim 1, characterized in that, A sealing piston (15) is tightly fitted on the central tube (3). The outer wall of the sealing piston (15) is in close contact with the inner wall of the lower liquid cylinder (84). A pair of limiting rings (16) are fixedly connected to the central tube (3), and the pair of limiting rings (16) abut against both sides of the sealing piston (15).

5. The double-tube layered packer according to claim 1, characterized in that, The lower piston (85) has an assembly hole (19), the sealing assembly (7) is disposed in the assembly hole (19), and the central tube (3) has a sealing ring groove (20) that communicates with the assembly hole (19). When the lower piston (85) moves downward and the lower rubber sleeve (62) is seated on the inner wall of the sleeve, and the top of the lower piston (85) moves to the position of the sealing ring groove (20), the ring cavity of the lower piston (85) communicates with the sealing ring groove (20).

6. The double-tube layered packer according to claim 5, characterized in that, The seal verification component (7) includes: A support nut (71) is threaded into the assembly hole (19); A rupture disc (72) is disposed at the bottom port of the support nut (71); A sandproof cover plate (73) is provided at the top port of the supporting nut (71); A welding ring (74) is fixed to the bottom end of the support nut (71).

7. A method for operating a double-tube layered packer according to any one of claims 1-6, characterized in that, Includes the following steps: S1, the packer is lowered into the casing and pressure is applied to the packer by the ground pressure equipment. Under the pressure, the motion component (8) controls the upper rubber sleeve component (5) and the lower rubber sleeve component (6) to sit on the inner wall of the casing respectively. S2, pressurize the packer through the ground pressurization equipment, and the sealing test assembly (7) performs a sealing test on the annulus between the upper rubber tube assembly (5) and the lower rubber tube assembly (6).

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