An inflatable insert packer

Abstract

This invention provides an expandable insert packer, including an expandable anchor, an outer anchor tube (an expandable alloy tube), and internally, from top to bottom, a locking section, an expansion section, and a launch chamber section; a return tube is connected to the lower end of the outer anchor tube; the launch chamber contains a swing-type expansion head, a pressure-bearing piston, and a bottom plug device, forming a sealed chamber between the pressure-bearing piston and the bottom plug device; a self-locking inserter has a self-locking mechanism consisting of a locking pin and a claw on the outer peripheral wall of the insert tube, and three sets of insert sealing rings and corresponding compensation rings arranged axially; the expandable anchor hydraulically pushes the swing-type expansion head upward, causing the outer anchor tube to expand radially, driving the anchoring rubber ring to adhere to the inner wall of the casing; the self-locking inserter is inserted into the expanded outer anchor tube, and the locking pin and claw engage with the locking section, causing the insert sealing ring to adhere to the inner wall of the outer anchor tube; thus forming two independent sealing systems between the outer anchor tube and the casing, and between the insert tube and the outer anchor tube.

Description

Technical Field

[0001] This invention relates to an expandable insert packer, and pertains to the field of downhole tool technology. Background Technology

[0002] Packers are widely used in the petroleum industry as a tool. Numerous types and models of packers are used in oil, gas, and water wells. The expansion function of the rubber components plays a crucial role in their structure, achieving the purpose of sealing the producing layer and facilitating operations. Currently, packers have the following shortcomings and problems that need to be solved: 1. Seal failure: Packers operate in harsh environments for extended periods, and the aging and damage of the sealing rubber components are accelerated by temperature and alternating dynamic forces. Uneven stress on the rubber leads to leakage and loss of sealing performance.

[0003] 2. Aging of machine parts: Insufficient structural design, material selection, and machining precision, as well as fatigue fracture of the main component, the slip mechanism, under alternating loads, and the effects of suction and jacking, cause the components to lose their function.

[0004] 3. Unable to be sealed off: The selected setting location was compromised by bushing deformation, severe corrosion, and substandard product quality, preventing the packer from setting.

[0005] 4. Difficulty in lifting the lockdown: Wells where packers are installed often experience severe sand production and corrosion, and factors such as rubber aging and deformation make packer replacement difficult. Summary of the Invention

[0006] To address the problems arising from the aforementioned background technology, this invention provides an expansion-insertion packer. The specific technical solution is as follows: An expansion-insertion packer, comprising: An expansion anchor includes an outer anchor tube, which is an expansion alloy tube. From top to bottom, the outer anchor tube consists of a locking section, an expansion section with a vulcanized anchoring ring, and a launching chamber section. The launching chamber is equipped with a swing-type expansion head, a pressure-bearing piston, and a bottom plug device. A sealed chamber is formed between the pressure-bearing piston and the bottom plug device. A return tube is connected to the lower end of the outer anchor tube. The self-locking inserter includes a tubing connector, a locking cap, a locking pin, a claw, a straightening tube, and an insert tube; the outer peripheral wall of the insert tube is provided with a self-locking mechanism composed of the locking pin and the claw, as well as three sets of insert sealing rings and corresponding compensation rings arranged along the axial direction; The expansion anchor is hydraulically pushed upward by the pendulum expansion head, causing the outer anchor tube to expand radially and causing the anchoring rubber ring to adhere to the inner wall of the casing. The self-locking inserter is inserted into the expanded outer anchor tube and engages with the locking section through the locking pin and the cat claw, so that the insertion sealing ring adheres to the inner wall of the outer anchor tube. This constitutes two independent sealing systems between the outer anchor tube and the casing, and between the insert tube and the outer anchor tube.

[0007] Furthermore, three sets of sealing assemblies are provided axially on the outer peripheral wall of the insertion tube, each set including 5 insertion sealing rings and 5 compensation rings; The first group is located at the top of the insertion tube, the second group is located in the middle of the insertion tube, and the third group is located at the bottom of the insertion tube. In each group, the insertion sealing ring and the compensation ring are arranged alternately, with the compensation ring located on both sides of the insertion sealing ring.

[0008] Furthermore, the insertion sealing ring is a sealing ring made of polymer material; the compensation ring is a Glyd ring or an expanded rubber ring, whose elastic modulus is lower than that of the insertion sealing ring, and is used to preferentially deform under pressure and push the insertion sealing ring to expand radially.

[0009] Furthermore, the expansion section of the outer anchor tube has 8-12 anchoring rings vulcanized, wherein the first and last anchoring rings contain implicit hard suspension rings; the outer diameter of the outer anchor tube before expansion is... 108mm~ 110mm, wall thickness 5mm~8mm, outer diameter after expansion is 119mm~ The wall thickness is 122mm, and the wall thickness after expansion is the same as the wall thickness before expansion, while the axial length is shortened accordingly; the starting pressure of the swing expansion head is 24MPa, and the working pressure is 28-35MPa.

[0010] Furthermore, the length of the latch section is 150mm, the length of the trapezoidal latch is 102mm, and it is formed by pre-expansion shaping; the cat claw is made of spring steel after heat treatment and has 8 grooves; the locking post has 8 protrusions, and the grooves and protrusions slide together to form a lockable connection.

[0011] Furthermore, the bottom plug device includes a sealing piston, a one-way valve, and a filter; under hydraulic action, the bottom plug device is fixed to the lower part of the outer anchor pipe, forming a sealed chamber together with the pressure-bearing piston, serving as the launching base for the upward movement of the pendulum expansion head.

[0012] Furthermore, the expansion anchor also includes: a tension cap, a central tube, a safety joint, an expansion head sub-section, a universal joint seat, and a universal joint; the swing expansion head is connected to the central tube through the expansion head sub-section, and the universal joint is connected to the bottom plug device; the expansion anchor also includes a falling object prevention cap, which is located at the top of the annular space between the central tube and the outer anchor tube.

[0013] Furthermore, under the hydraulic pressure of 24-35 MPa, the expansion anchor drives the pendulum expansion head to move upward from the firing chamber section to the locking section along the inner wall of the outer anchor tube, causing the outer anchor tube to expand radially; after the expansion is completed, the central tube drives the pendulum expansion head, the pressure-bearing piston and the bottom plug device to move upward and separate from the outer anchor tube as a whole.

[0014] Furthermore, under the suspension of a weight of 2 to 6 tons, the self-locking inserter causes the insert tube to enter the inner cavity of the outer anchor tube and drives the cat claw to extend and retract radially to engage with the trapezoidal buckle of the locking section, thereby achieving locking.

[0015] A method for installing an inflatable packer, using an inflatable packer as described in any of the preceding claims, the method comprising anchoring and insertion locking: The anchoring is: The expansion anchor is lowered to the predetermined well depth through the tubing string. After closing the one-way valve in the bottom plug device, fluid is pumped into the central pipe. When the pressure inside the sealed chamber reaches 24MPa, the pendulum expansion head is driven to start moving upward; when the pressure reaches 28-35MPa, in conjunction with the upward pulling force of the tubing string, the pendulum expansion head is driven to pass through the anchoring rubber ring on the expansion section of the outer anchor pipe in sequence. When the swing expansion head enters the locking section and reaches the top of the outer anchor tube, the pressure drops to zero, completing the anchoring and sealing of the expansion anchor. Lift the central tube to detach the central tube, safety joint, swing expansion head, pressure piston, bottom plug device and anti-falling object cap from the outer anchor tube as a whole; The insertion lock is: Connect the self-locking inserter to the drill string through the tubing connector, and lower it above the already anchored outer anchor pipe. Confirm the position of the top of the outer anchor pipe by changing the suspension weight. The cat claw is lowered in stages and a suspension weight of 2-6T is applied to drive the radial extension and retraction of the cat claw to engage with the trapezoidal buckle of the locking section, thereby completing the insertion and locking of the self-locking inserter.

[0016] The beneficial effects of this invention compared to the prior art are as follows: This invention establishes two independent sealing systems—an expansion anchor and a self-locking inserter—between the outer anchor tube and the casing, and between the inserter and the inner wall of the outer anchor tube. The first sealing system consists of an anchoring ring that adheres to the inner wall of the casing after the outer anchor tube expands radially. The second sealing system consists of an insertion sealing ring on the outer circumferential wall of the inserter that adheres to the inner wall of the outer anchor tube. These two sealing systems are independent of each other; if one fails, the other can still maintain a seal, significantly improving the overall sealing reliability of the packer.

[0017] The insertion tube has three sets of rubber sealing assemblies on its outer diameter. Each set includes five insertion sealing rings and five compensation rings, which are arranged alternately. The elastic modulus of the compensation rings is lower than that of the insertion sealing rings. Under pressure, they deform preferentially and ensure the radial expansion of the insertion sealing rings to form a pneumatic seal. This seal can adapt to alternating loads caused by downhole temperature changes, pressure fluctuations, and tubing vibrations.

[0018] The outer diameter of the external anchor tube before expansion is 108mm~ 110mm, wall thickness 5mm~8mm, outer diameter after expansion is 119mm~ The expansion anchor has a diameter of 122mm, and the wall thickness after expansion is the same as that before expansion, while the axial length is shortened accordingly. After the expansion anchor is fixed to the inner wall of the casing, the internal diameter is large enough to meet the diameter requirements of subsequent sand flushing, logging, well workover and other construction operations, which is incomparable to general structure packers.

[0019] The expandable anchor and the self-locking inserter are separate components. In the expandable anchor, the bottom plug is fixed to the lower part of the outer anchor tube under hydraulic pressure, forming a sealed chamber together with the pressure-bearing piston. After anchoring is completed, only the outer anchor tube and the return sleeve remain downhole, while all other components are returned to the surface. The self-locking inserter retains only essential components downhole, significantly reducing the probability of damage to downhole equipment.

[0020] Under hydraulic pressure of 24–35 MPa, the outer anchor tube drives the pendulum expansion head upward, causing the outer anchor tube to expand radially and causing the anchoring rubber ring to tightly adhere to the inner wall of the casing. This anchoring method creates a dual combination of mechanical anchoring and rubber sealing between the outer anchor tube and the casing, providing excellent pull-out resistance and solving problems such as failure to set and displacement of existing packers.

[0021] The self-locking inserter, under a suspension load of 2-6T, allows the insert tube to enter the outer anchor tube and drives the cat claw to extend and retract radially, engaging with the trapezoidal buckle of the locking section to achieve locking. This locking method is simple to operate, reliable in locking, and requires no additional rotation or lifting action.

[0022] The inserter's insertion sealing ring is made of polymer material. The elastic modulus of the compensation ring and the expansion rubber ring is lower than that of the insertion sealing ring, so they deform preferentially and ensure the radial expansion of the sealing ring, maintaining stable sealing performance during long-term downhole use. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the expansion insertion packer of the present invention; Figure 2 for Figure 1 Enlarged view of the structure at point AA; Figure 3 for Figure 1Enlarged view of the structure at point BB; Figure 4 This is a schematic diagram of the expansion anchor in this invention; Figure 5 for Figure 4 Enlarged view of the structure at point C; Figure 6 for Figure 4 Enlarged view of the structure at point DD; Figure 7 This is a schematic diagram of the self-locking inserter in this invention; Figure 8 for Figure 7 Enlarged view of the structure at the EE section; Figure 9 for Figure 7 Enlarged view of the structure at the FF position.

[0024] Figure label: 1. Pipe joint; 2. Center tube; 3. Lock cap; 4. Locking column; 5. Cat's paw; 6. External anchor tube; 7. Straightening tube; 8. Anchoring rubber ring; 9. Rigid suspension ring; 10. Return sleeve; 11. Insertion tube; 12. Insertion sealing ring; 13. Compensation ring; 14. Tension-bearing tube cap; 15. Tension-bearing tube; 16. Anti-falling object cap; 17. Safety joint; 18. Expansion head short section; 19. Swing expansion head; 20. Pressure-bearing piston; 21. Bottom plug device; 22. Universal joint seat; 23. Universal joint; 24. Sleeve; 25. Filter. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1 like Figure 1-9 As shown, an expansion-insertion packer includes: The expansion anchor includes an outer anchor tube 6, which is an expansion alloy tube. From top to bottom, the outer anchor tube 6 consists of a locking section, an expansion section with a vulcanized anchoring ring 8, and a launching chamber section. The launching chamber is equipped with a swing-type expansion head 19, a pressure-bearing piston 20, and a bottom plug device 21. A sealed chamber is formed between the pressure-bearing piston and the bottom plug device. The lower end of the outer anchor tube 6 is connected to a return tube 10. The self-locking inserter includes a tubing connector 1, a locking cap 3, a locking pin 4, a cat claw 5, a straightening tube 7, and an insertion tube 11; the outer peripheral wall of the insertion tube 11 is provided with a self-locking mechanism composed of the locking pin 4 and the cat claw 5, as well as three sets of insertion sealing rings and corresponding compensation rings arranged along the axial direction. The expansion anchor is hydraulically pushed upward by the swing expansion head 19, causing the outer anchor tube 6 to expand radially, which in turn causes the anchoring rubber ring 8 to adhere to the inner wall of the casing. The self-locking inserter is inserted into the expanded outer anchor tube 6, and the locking pin 4 and the cat claw 5 engage with the locking section, so that the insertion sealing ring adheres to the inner wall of the outer anchor tube. This forms two independent sealing systems between the outer anchor tube and the casing, and between the insert tube and the outer anchor tube.

[0027] Three sets of sealing components are provided axially on the outer peripheral wall of the insertion tube 11, each set including 5 insertion sealing rings 12 and 5 compensation rings 13; The first group is located at the top of the insertion tube, the second group is located in the middle of the insertion tube, and the third group is located at the bottom of the insertion tube. In each group, the insertion sealing ring 12 and the compensation ring 13 are arranged alternately, with the compensation ring 13 located on both sides of the insertion sealing ring 12.

[0028] The insertion sealing ring 12 is a sealing ring made of polymer material; the compensation ring 13 is a Glyd ring or an expanded rubber ring with a lower elastic modulus than the insertion sealing ring 12, and is used to preferentially deform under pressure and push the insertion sealing ring to expand radially.

[0029] The expansion section of the outer anchor tube 6 has 8-12 anchoring rings 8, among which the first and last anchoring rings contain hidden hard suspension rings 9; the outer diameter of the outer anchor tube 6 before expansion is 108mm~ 110mm, wall thickness 5mm~8mm, outer diameter after expansion is 119mm~ The wall thickness is 122mm, and the wall thickness after expansion is the same as that before expansion, and the axial length is shortened accordingly; the starting pressure of the swing expansion head 19 is 24MPa, and the working pressure is 28~35MPa.

[0030] The length of the locking section is 150mm, and the length of the trapezoidal locking section is 102mm. It is formed by pre-expansion shaping. The cat claw 5 is made of spring steel after heat treatment and has 8 grooves. The locking post 4 has 8 protrusions. The grooves and protrusions slide together to form a lockable connection.

[0031] The bottom plug device 21 includes a sealing piston, a one-way valve, and a filter 25. Under hydraulic pressure, the bottom plug device is fixed to the lower part of the outer anchor pipe and together with the pressure-bearing piston 20 forms a sealed chamber, which serves as the launching base for the upward movement of the swing expansion head 19.

[0032] The expansion anchor also includes: a tension cap 14, a central tube 2, a safety joint 17, an expansion head stub 18, a universal joint seat 22, and a universal joint 23; the swing expansion head 19 is connected to the central tube 2 through the expansion head stub 18, and the universal joint 23 is connected to the bottom plug device 21; the expansion anchor also includes a falling object cap 16, which is located at the top of the annular space between the central tube 2 and the outer anchor tube 6.

[0033] Under the hydraulic pressure of 24-35MPa, the expansion anchor drives the pendulum expansion head 19 to move upward from the firing chamber section to the locking section along the inner wall of the outer anchor tube 6, causing the outer anchor tube to expand radially. After the expansion is completed, the central tube 2 drives the pendulum expansion head 19, the pressure-bearing piston 20 and the bottom plug device 21 to move upward and separate from the outer anchor tube 6 as a whole.

[0034] Under the suspension of 2 to 6 tons, the self-locking inserter causes the insertion tube 11 to enter the inner cavity of the outer anchor tube 6 and drives the cat claw 5 to extend and retract radially to engage with the trapezoidal buckle of the locking section, thereby achieving locking.

[0035] Example 2 A method for installing an inflatable packer, using any of the above-mentioned inflatable packers, the method comprising anchoring and insertion locking: Anchored as: The expansion anchor is lowered to the predetermined well depth through the tubing string. After closing the one-way valve in the bottom plug device 21, liquid is pumped into the central pipe 2. When the pressure in the sealed chamber reaches 24MPa, the pendulum expansion head 19 is driven to start moving upward; when the pressure reaches 28-35MPa, in conjunction with the upward pulling force of the tubing, the pendulum expansion head 19 is driven to pass through the anchoring rubber ring 8 on the expansion section of the outer anchor pipe 6 in sequence. When the swing expansion head 19 enters the locking section and reaches the top of the outer anchor tube 6, the pressure drops to zero, completing the anchoring and sealing of the expansion anchor. Lift the central tube 2, so that the central tube 2, safety joint 17, swing expansion head 19, pressure piston 20, bottom plug device 21 and anti-falling object cap 16 are completely separated from the outer anchor tube 6. Insertion locking is: Connect the self-locking inserter to the drill string through the tubing connector 1, and lower it above the anchored outer anchor pipe 6. Confirm the position of the top of the outer anchor pipe 6 by changing the weight. The cat claw 5 is lowered in stages and a suspension weight of 2-6T is applied to drive the radial extension and retraction of the cat claw 5 to engage with the trapezoidal buckle of the locking section, thus completing the insertion and locking of the self-locking inserter.

[0036] Example 3 In one feasible embodiment, the technical solution of the present invention and the characteristics of the expandable insert packer were combined and the field application verification was carried out in well 309-6 of an oil field.

[0037] I. Basic Data The well casing has an outer diameter of 139.7 mm and an inner diameter of 124 mm. The tool depth is 1775.07 meters, and the maximum outer diameter of the tool is 118 mm. The external anchor pipe has a pre-expansion diameter of φ108 mm, a pre-expansion wall thickness of 8 mm, and a pre-expansion inner diameter of φ92 mm; the swing-type expansion head has a diameter ≥φ106 mm; after expansion, the external anchor pipe has an outer diameter of φ122 mm and an inner diameter of φ106 mm; the anchoring ring has an outer diameter ≥φ124 mm after expansion. The return sleeve has an outer diameter of φ121 mm and an inner diameter of φ108 mm; the insertion pipe has a maximum outer diameter of φ107 mm and an inner diameter of φ94 mm.

[0038] II. Construction Steps 1. Wellbore treatment Before construction, the original well string was pulled out, and wellbore treatment procedures such as milling and cleaning, pipe scraping, engineering logging, simulated well cleaning, and wellbore leakage detection were carried out in sequence to make the wellbore conditions meet the requirements for running in an expandable insert packer.

[0039] 2. Insert the expansion anchor. The tubular structure consists of an expansion anchor (including a return sleeve) connection. 73mm tubing to the wellhead. Lower the expansion anchor to the predetermined well depth of 1775.07 meters.

[0040] The expansion anchor includes an outer anchor tube, a central tube, a support cap, a support tube, a fall arrestor cap, a safety joint, an expansion head sub-section, a swing-type expansion head, a pressure-bearing piston, a universal joint seat, a universal joint, and a bottom plug device. The swing-type expansion head is connected to the central tube via the expansion head sub-section, the universal joint connects to the bottom plug device, and the fall arrestor cap is located at the top of the annular space between the central tube and the outer anchor tube.

[0041] Close the check valve in the bottom plug device (which also includes a sealing piston and filter 25), and pump liquid into the central tube. When the pressure in the sealing chamber reaches 24 MPa, the pendulum expansion head is driven to move upward; when the pressure reaches 28 to 35 MPa, in conjunction with the upward pulling force of the tubing, the pendulum expansion head is driven to pass through the 12 anchoring rubber rings on the expansion section of the outer anchor tube in sequence. When the pendulum expansion head enters the locking section and reaches the top of the outer anchor tube, the pressure drops sharply to zero, completing the anchoring and sealing of the expansion anchor.

[0042] The locking section is 150mm long, and the trapezoidal locking section is 102mm long, both formed by pre-expansion shaping.

[0043] At this time, the outer anchor tube expands radially, causing the anchoring rubber ring to fit tightly against the inner wall of the casing. The hard suspension rings hidden in the first and twelfth anchoring rubber rings are embedded in the inner wall of the casing by 0.2 to 0.5 mm, forming the first sealing system.

[0044] Raise the center pipe to detach the center pipe, safety joint, swing expansion head, pressure piston, bottom plug device, and anti-falling object cap from the outer anchor pipe. After anchoring is completed, only the outer anchor pipe and return sleeve remain downhole, while all other components are returned to the surface.

[0045] 3. Pressure test Pressurize the well with clean water to 35 MPa, stabilize the pressure for 30 minutes, and the pressure drop is 0.3 MPa. The pressure test is qualified.

[0046] 4. Insert the self-locking inserter. The tubing string structure is as follows: a self-locking inserter connects φ73mm tubing to the wellhead. The self-locking inserter includes a tubing string connector, a center tube, a locking cap, a locking pin, cat claws, a centralizing tube, and an insert tube. The locking cap, locking pin, and cat claws form the self-locking mechanism. The cat claws are made of heat-treated spring steel and have eight grooves. The locking pin has eight protrusions; the grooves and protrusions slide together to form a lockable connection. The centralizing tube is attached to the lower part of the self-locking mechanism.

[0047] Connect the self-locking inserter to the drill string via the tubing connector and lower it above the anchored outer anchor pipe. Perform trial insertion by varying the suspended weight to confirm the position of the top of the outer anchor pipe. Lift the tubing string, mark it, align it with the top of the outer anchor pipe, and lower it in stages, applying a suspended weight of 2 to 6 tons. Drive the claw mechanism to extend radially and engage with the trapezoidal locking mechanism of the locking section, completing the insertion and locking of the self-locking inserter.

[0048] Three sets of sealing assemblies are provided axially on the outer peripheral wall of the insertion tube. Each set includes five insertion sealing rings and five compensation rings, which are arranged alternately. The compensation rings are located on both sides of the insertion sealing rings. The first set is located at the upper part of the insertion tube, the second set is located at the middle part of the insertion tube, and the third set is located at the lower part of the insertion tube.

[0049] The insertion sealing ring is made of a polymer material, while the elastic modulus of the compensation ring and the expansion rubber ring is lower than that of the insertion sealing ring. Under pressure, the compensation ring deforms preferentially, ensuring the radial expansion of the insertion sealing ring.

[0050] After the insertion tube enters the outer anchor tube, the insertion sealing ring fits against the inner wall of the outer anchor tube, forming a second sealing system.

[0051] 5. Final pressure test The water pressure was increased to 15 to 20 MPa again, and the pressure was stabilized for 30 minutes. The pressure drop was ≤0.3 MPa, and the pressure test was qualified, confirming that the expansion insert packer was successfully set.

[0052] III. Application Effects Field verification showed that the expansion-insertion packer of the present invention has the following effects: First, the two independent sealing systems operate reliably. The two sealing systems between the outer anchor pipe and the casing, and between the insertion pipe and the inner wall of the outer anchor pipe, are independent of each other. The pressure test reached 35 MPa, and the pressure drop was only 0.3 MPa, demonstrating excellent sealing performance.

[0053] Secondly, the alternating arrangement of the insertion sealing ring and the compensation ring effectively adapts to alternating loads. After 10 repeated insertions and removals of the self-locking inserter, no significant wear was observed on the insertion sealing ring, while slight wear was observed on the compensation ring. The average insertion pressure was approximately 1.6 MPa (about 2.5 tons), and the sealing performance remained stable.

[0054] Third, the modular design reduces the probability of damage to downhole components. After the expansion anchor is anchored, only the outer anchor tube and the return sleeve remain downhole, while all other components are returned to the surface; for the self-locking inserter, only the insertion tube and sealing components remain downhole, and vulnerable parts can be replaced on-site.

[0055] Fourth, the expansion anchoring method has excellent pull-out resistance. After the outer anchor tube expands, it forms a dual combination of mechanical anchoring and rubber sealing with the casing, solving the problems of existing packers failing to set and shifting.

Claims

1. An inflatable, insert packer characterized by, include: The expansion anchor includes an outer anchor tube (6), which is an expansion alloy tube. The outer anchor tube (6) consists of a locking section, an expansion section with a vulcanized anchoring ring (8), and a launching chamber section from top to bottom. The launching chamber is equipped with a swing expansion head (19), a pressure-bearing piston (20), and a bottom plug device (21). A sealed chamber is formed between the pressure-bearing piston and the bottom plug device. A return tube (10) is connected to the lower end of the outer anchor tube (6). The self-locking inserter includes a tubing connector (1), a locking cap (3), a locking pin (4), a cat claw (5), a straightening tube (7), and an insert tube (11); the outer peripheral wall of the insert tube (11) is provided with a self-locking mechanism composed of the locking pin (4) and the cat claw (5), as well as three sets of insert sealing rings and corresponding compensation rings arranged along the axial direction; The expansion anchor is hydraulically pushed upward by the swing expansion head (19), causing the outer anchor tube (6) to expand radially, which in turn causes the anchoring rubber ring (8) to adhere to the inner wall of the casing. The self-locking inserter is inserted into the expanded outer anchor tube (6), and the locking pin (4) engages with the cat claw (5) in the locking section, so that the insertion sealing ring adheres to the inner wall of the outer anchor tube. This forms two independent sealing systems between the outer anchor tube and the casing, and between the insert tube and the outer anchor tube.

2. The packer of claim 1, wherein, The outer peripheral wall of the insertion tube (11) is provided with three sets of sealing components along the axial direction, each set including 5 insertion sealing rings (12) and 5 compensation rings (13). The first group is located at the top of the insertion tube, the second group is located in the middle of the insertion tube, and the third group is located at the bottom of the insertion tube. In each group, the insertion sealing ring (12) and the compensation ring (13) are arranged alternately, and the compensation ring (13) is located on both sides of the insertion sealing ring (12).

3. The packer according to claim 2, characterized in that, The insertion sealing ring (12) is a sealing ring made of polymer material; the compensation ring (13) is a Glyd ring or an expanded rubber ring with an elastic modulus lower than that of the insertion sealing ring (12), and is used to preferentially deform under pressure and push the insertion sealing ring to expand radially.

4. The packer of claim 1, wherein, The expansion section of the outer anchor tube (6) has 8-12 anchoring rubber rings (8) vulcanized, wherein the first and last anchoring rubber rings contain hidden hard suspension rings (9); the outer diameter of the outer anchor tube (6) before expansion is 108mm~ 110mm, wall thickness 5mm~8mm, outer diameter after expansion is 119mm~ The wall thickness after expansion is 122mm, and the wall thickness after expansion is the same as that before expansion, and the axial length is shortened accordingly; the starting pressure of the swing expansion head (19) is 24MPa, and the working pressure is 28~35MPa.

5. The packer of claim 1, wherein, The length of the locking section is 150mm, and the length of the trapezoidal buckle is 102mm. It is formed by pre-expansion shaping. The cat claw (5) is made of spring steel after heat treatment and has 8 grooves. The locking post (4) has 8 protrusions. The grooves and protrusions slide together to form a lockable connection.

6. The packer of claim 1, wherein, The bottom plug device (21) includes a sealing piston, a flow valve and a filter (25); under hydraulic action, the bottom plug device is fixed to the lower part of the outer anchor pipe and together with the pressure-bearing piston (20) forms a sealed chamber, which serves as the launching base for the upward movement of the swing expansion head (19).

7. The packer of claim 1, wherein, The expansion anchor also includes: a tension cap (14), a central tube (2), a safety joint (17), an expansion head short section (18), a universal joint seat (22), and a universal joint (23); the swing expansion head (19) is connected to the central tube (2) through the expansion head short section (18), and the universal joint (23) is connected to the bottom plug device (21); the expansion anchor also includes a falling object cap (16), which is located at the top of the annular space between the central tube (2) and the outer anchor tube (6).

8. The packer of claim 1, wherein, Under the hydraulic pressure of 24-35 MPa, the expansion anchor drives the swing expansion head (19) to move upward from the launching chamber section to the locking section along the inner wall of the outer anchor tube (6), causing the outer anchor tube to expand radially; after the expansion is completed, the central tube (2) drives the swing expansion head (19), the pressure piston (20) and the bottom plug device (21) to move upward and separate from the outer anchor tube (6) as a whole.

9. The packer of claim 1, wherein, Under the suspension of 2 to 6T, the self-locking inserter causes the insertion tube (11) to enter the inner cavity of the outer anchor tube (6) and drives the cat claw (5) to extend and retract radially to engage with the trapezoidal buckle of the locking section, thereby achieving locking.

10. A method for constructing an expandable insert packer, using the expandable insert packer according to any one of claims 1-9, the method comprising anchoring and insertion locking: The anchoring is: The expansion anchor is lowered to the predetermined well depth through the tubing string. After closing the one-way valve in the bottom plug device, fluid is pumped into the central pipe. When the pressure inside the sealed chamber reaches 24MPa, the pendulum expansion head is driven to start moving upward; when the pressure reaches 28-35MPa, in conjunction with the upward pulling force of the tubing string, the pendulum expansion head is driven to pass through the anchoring rubber ring on the expansion section of the outer anchor pipe in sequence. When the swing expansion head enters the locking section and reaches the top of the outer anchor tube, the pressure drops to zero, completing the anchoring and sealing of the expansion anchor. Lift the central tube to detach the central tube, safety joint, swing expansion head, pressure piston, bottom plug device and anti-falling object cap from the outer anchor tube as a whole; The insertion lock is: Connect the self-locking inserter to the drill string through the tubing connector, and lower it above the already anchored outer anchor pipe. Confirm the position of the top of the outer anchor pipe by changing the suspension weight. The cat claw is lowered in stages and a suspension weight of 2-6T is applied to drive the radial extension and retraction of the cat claw to engage with the trapezoidal buckle of the locking section, thereby completing the insertion and locking of the self-locking inserter.

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