Anti-stuck water injection packer

Abstract

This utility model discloses an anti-jamming water injection packer in the field of downhole water injection tool technology. It includes an upper connector, with a rotary release connector screwed to the lower end of the upper connector and sealed to it. The lower part of the rotary release connector is connected to a central tube via a reverse-threaded internal thread. An upper cap is screwed to the outer circumference of the upper end of the central tube and connected to the inner wall of the upper end of the rotary release connector via a rotary release shear pin. A backwashing mechanism is connected below the rotary release connector, and a setting mechanism is connected below the backwashing mechanism. A hydraulic drive mechanism is located below the setting mechanism, and a lower connector is connected below the hydraulic drive mechanism. When the anti-jamming water injection packer cannot be normally released by lifting, it can be released by rotating the tubing string, effectively solving the problem of release difficulties caused by scaling, casing dirt, etc., reducing the risk of major overhauls, and improving the reliability and service life of the water injection packer.

Description

Technical Field

[0001] This utility model relates to an anti-jamming water injection sealer, belonging to the technical field of layered water injection tools. Background Technology

[0002] To maintain reservoir pressure and sustain production, water injection is necessary. For multi-layer water injection, stratified water injection is required to adjust inter-layer imbalances, control the rise in crude oil water content, and improve oil recovery. Water packers are an important tool for sealing off oil reservoirs.

[0003] However, existing water injection packers have some problems during long-term water injection. For example, Chinese utility model patent CN202181873U discloses a water injection packer, but in practical applications, the unsealing mechanism is prone to scaling, causing the packer to often fail to unseal smoothly when the injection tubing needs to be removed. Furthermore, Chinese patent application CN105696966A discloses an anti-erosion packer with a cup-type structure. This structure, when dirt accumulates on the well casing wall on the expanded packer sleeve, increases the friction between the injection tubing and the well casing, leading to the injection tubing jamming and requiring major repairs.

[0004] Therefore, in downhole stratified water injection practice, there is an urgent need to develop a water injection packer that can be unsealed normally without being affected by scale or casing dirt. Utility Model Content

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, and such simplifications or omissions should not be construed as limiting the scope of the present invention.

[0006] The purpose of this invention is to overcome the problems existing in the prior art and provide an anti-jamming water injection packer that can still be successfully unsealed after long-term downhole operation, even when the unsealing mechanism is scaled or the casing is jammed by debris.

[0007] To solve the above technical problems, this utility model provides an anti-jamming water-filled packer, including an upper connector, the lower end of which is screwed with a rotary release connector and they are sealed to each other. The lower part of the rotary release connector is connected to a central tube through a reverse-threaded internal thread. An upper cap is screwed onto the outer circumference of the upper end of the central tube and is connected to the inner wall of the upper end of the rotary release connector through a rotary release shear pin. A backwashing mechanism is connected below the rotary release connector, and a setting mechanism is connected below the backwashing mechanism. A hydraulic drive mechanism is provided below the setting mechanism, and a lower connector is connected below the hydraulic drive mechanism.

[0008] Furthermore, the backwashing mechanism includes an upper backwashing sleeve, a backwashing piston, and a backwashing piston seat. The upper backwashing sleeve is screwed to the lower part of the rotary unsealing joint. The backwashing piston is located in the inner cavity of the upper backwashing sleeve and is sleeved on the outer periphery of the central tube. The upper end of the backwashing piston is sealed to the central tube and the upper backwashing sleeve respectively. The lower part of the upper backwashing sleeve is provided with a backwashing liquid inlet hole. The backwashing piston seat is connected to the lower end of the upper backwashing sleeve.

[0009] Furthermore, the upper end of the backwash piston seat is provided with a flared opening, and the lower end of the backwash piston is fitted with a sealing ring and pressed by a pressure ring. The outer conical surface of the sealing ring matches the inner conical surface of the flared opening of the backwash piston seat.

[0010] Furthermore, the setting mechanism includes a rubber tube, a spacer ring, and a rubber tube bushing. The rubber tube bushing is fitted around the outer periphery of the central tube with a gap between it and the central tube. The rubber tube is fitted around the outer periphery of the rubber tube bushing. Adjacent rubber tubes are separated by spacer rings. The top rubber tube abuts against the bottom of the backwash piston seat.

[0011] Furthermore, the bottom rubber sleeve rests against the top of the lower backwash sleeve, and the lower backwash sleeve has a backwash outlet hole in the middle; the lower inner circumference of the backwash piston has an annular space for the rubber sleeve bushing to be inserted, and the inner wall of the annular space is fitted with a sealing ring.

[0012] Furthermore, the hydraulic drive mechanism includes an upper cylinder, a lower central tube, and a lower cylinder. The upper cylinder is connected below the lower backwash sleeve and its upper part is sealed to the outer wall of the central tube. The lower central tube is connected to the lower end of the central tube, and the lower cylinder is connected below the upper cylinder and its upper part is sealed to the outer wall of the lower central tube. The central tube has a through hole communicating with the hydraulic chamber of the upper cylinder, and the lower central tube has a through hole communicating with the hydraulic chamber of the lower cylinder.

[0013] Furthermore, the lower connector is connected to the lower end of the lower central tube, and the outer wall of the upper large-diameter section of the lower connector is fitted with a sealing ring to seal the lower inner wall of the lower liquid cylinder.

[0014] Furthermore, a locking ring is fitted below the middle step of the lower connector, and the locking ring seat is fixed to the outer periphery of the lower connector and located below the locking ring by an upward lifting release shear pin. The outer wall of the locking ring is provided with external ratchet teeth; the lower section of the lower liquid cylinder is connected to a locking sleeve, and the inner wall of the locking sleeve is provided with internal ratchet teeth.

[0015] Furthermore, a setting ring is connected to the lower part of the lock sleeve, and a parallel ring is provided on the outer periphery of the middle part of the lower connector. The setting ring and the parallel ring are fixedly connected by a setting shear pin. The top outer edge of the parallel ring abuts against the lower part of the lock sleeve, and the lower end of the parallel cap is connected to the middle external thread of the lower connector.

[0016] Compared with the prior art, this utility model has achieved the following beneficial effects: a rotating unsealing mechanism is installed inside the water injection packer. When the water injection packer cannot be unsealed normally when it is lifted, the packer can be unsealed by rotating the tubing. This effectively solves the problem of unsealing difficulties caused by scaling, casing dirt and other problems, reduces the risk of major repairs, and improves the reliability and service life of the water injection packer. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. The drawings are provided for reference and illustration only and are not intended to limit this utility model. Wherein:

[0018] Figure 1 This is a cross-sectional view of the anti-jamming water-filled packer of this utility model;

[0019] In the diagram: 1. Upper connector; 2. Upper cap; 3. Rotary unsealing shear pin; 4. Rotary unsealing connector; 5. O-ring; 6. Central tube; 7. Upper backwash sleeve; 7a. Backwash inlet; 8. Backwash piston; 9. Sealing ring; 10. Pressure ring; 11. Backwash piston seat; 12. Rubber sleeve; 13. Spacer ring; 14. Rubber sleeve bushing; 15. Lower backwash sleeve; 15a. Backwash outlet; 16. Upper liquid cylinder; 17. Lower central tube; 18. Lower liquid cylinder; 19. Locking ring; 20. Upper unsealing shear pin; 21. Locking ring seat; 22. Locking sleeve; 23. Sealing ring; 24. Sealing shear pin; 25. Coupled ring; 26. Lower cap; 27. Lower connector. Detailed Implementation

[0020] In the following description of this utility model, the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not mean that the device must have a specific orientation.

[0021] To make the technical means, creative features, achieved objectives and effects of this utility model easier to understand, the present utility model will be further described below with reference to specific illustrations. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments.

[0022] 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 is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0023] like Figure 1 As shown, the anti-jamming water-filled packer of this utility model includes an upper connector 1, an upper cap 2, a rotary unsealing shear pin 3, a rotary unsealing connector 4, an O-ring 5, a central tube 6, an upper backwash sleeve 7, a backwash piston 8, a sealing ring 9, a pressure ring 10, a backwash piston seat 11, a rubber sleeve 12, a spacer ring 13, a rubber sleeve bushing 14, a lower backwash sleeve 15, an upper liquid cylinder 16, a lower central tube 17, a lower liquid cylinder 18, a locking ring 19, an upper unsealing shear pin 20, a locking ring seat 21, a locking sleeve 22, a setting ring 23, a setting shear pin 24, a parallel ring 25, a lower cap 26, and a lower connector 27.

[0024] The upper external thread of the rotary unsealing connector 4 is screwed onto the lower internal thread of the upper connector 1. Two O-rings 5 ​​are embedded below the upper external thread of the rotary unsealing connector 4, sealing the lower inner wall of the upper connector 1. The lower end of the upper connector 1 abuts against the outer step of the rotary unsealing connector 4. The lower reverse-threaded internal thread of the rotary unsealing connector 4 connects to the reverse-threaded external thread on the outer circumference of the central tube 6. The upper cap 2 is screwed onto the upper end of the central tube 6, with its outer wall abutting against the upper inner wall of the rotary unsealing connector 4. The rotary unsealing shear pin 3 secures the rotary unsealing connector 4 to the upper cap 2. The bottom of the upper cap 2 is supported on the upper step of the central tube 6.

[0025] The upper internal thread of the upper backwash sleeve 7 is screwed onto the outer periphery of the lower external thread of the rotary unsealing connector 4. Two O-rings are embedded below the lower external thread of the rotary unsealing connector 4 to achieve a seal with the upper inner wall of the upper backwash sleeve 7. The upper port of the upper backwash sleeve 7 abuts against the lower outer step of the rotary unsealing connector 4.

[0026] The backwash piston 8 is located between the outer wall of the central tube 6 and the inner wall of the upper backwash sleeve 7. The inner wall of the upper sealing section of the backwash piston 8 is fitted with two piston inner sealing rings to achieve a seal with the outer wall of the central tube 6, and the outer wall of the upper sealing section of the backwash piston 8 is fitted with two piston outer sealing rings to achieve a seal with the inner wall of the upper backwash sleeve 7.

[0027] The external thread of the pressure ring 10 is connected to the lower internal thread of the backwash piston 8, and the outer circumference of the pressure ring 10 is sealed with the lower port of the backwash piston 8 by a sealing ring 9. The lower inner circumference of the backwash piston 8 is provided with an annular cavity for the insertion of the rubber sleeve 14. Two sealing rings are embedded in the inner wall of the annular cavity so that the backwash piston 8 can be sealed with the upper outer wall of the rubber sleeve 14 after it moves down.

[0028] The upper external thread of the backwash piston seat 11 is connected to the lower internal thread of the upper backwash sleeve 7. The rubber sleeve 14 is fitted around the outer circumference of the central tube 6, with a gap between it and the central tube 6 to serve as a backwash fluid flow channel. A sealing ring is embedded in the lower inner wall of the backwash piston seat 11 to achieve a seal with the upper outer wall of the rubber sleeve 14. The upper end of the backwash piston seat 11 is provided with a flared opening. When the backwash piston 8 descends to engage with the backwash piston seat 11, the outer conical surface of the sealing ring 9 seals with the flared opening of the backwash piston seat 11.

[0029] The rubber sleeve 12 and spacer ring 13 are fitted around the outer periphery of the rubber sleeve bushing 14. The rubber sleeve 12 has three sections, which are separated from each other by the spacer ring 13. The top rubber sleeve abuts against the bottom of the backwash piston seat 11, and the bottom rubber sleeve abuts against the top of the lower backwash sleeve 15. The internal thread of the lower backwash sleeve 15 is screwed into the lower external thread of the rubber sleeve bushing 14 and sealed by a sealing ring.

[0030] The upper external thread of the upper liquid cylinder 16 is screwed into the lower internal thread of the lower backwash sleeve 15, and the lower end of the lower backwash sleeve 15 abuts against the outer step of the upper liquid cylinder 16.

[0031] The upper sealing section of the upper cylinder 16 is fitted with a sealing ring that seals the outer wall of the central tube 6. Below the sealing section is the hydraulic chamber of the upper cylinder 16. The lower part of the central tube 6 is provided with a radial hole that communicates with the hydraulic chamber of the upper cylinder 16.

[0032] The upper end of the lower central tube 17 is threaded to the lower end of the central tube 6, and the expanded section of the upper end of the lower central tube 17 is sealed to the inner wall below the hydraulic chamber of the upper cylinder 16 through a sealing ring.

[0033] The upper external thread of the lower liquid cylinder 18 is connected to the lower internal thread of the upper liquid cylinder 16. The inner wall of the upper sealing end of the lower liquid cylinder 18 is fitted with a sealing ring that seals the outer wall of the lower central tube 17. A hydraulic chamber is provided below the upper sealing end of the lower liquid cylinder 18. A radial hole is provided at the lower part of the lower central tube 17 that communicates with the hydraulic chamber of the lower liquid cylinder 18.

[0034] The upper end of the lower connector 27 is connected to the lower end of the lower central tube 17 via an internal thread. The outer wall of the upper large-diameter section of the lower connector 27 is fitted with a sealing ring that seals the inner wall below the sealing section of the lower liquid cylinder 18.

[0035] Locking ring 19 and locking ring seat 21 are fitted onto the outer periphery of the middle section of lower connector 27. The lifting release shear pin 20 fixes the locking ring seat 21 to the lower connector 27. The upper external thread of locking sleeve 22 connects to the lower internal thread of lower liquid cylinder 18. Locking sleeve 22 has internal ratchet teeth that engage unidirectionally with the external ratchet teeth of locking ring 19. The lower external thread of locking sleeve 22 connects to the upper internal thread of setting ring 23. A coupling ring 25 is fitted onto the outer periphery of the middle section of lower connector 27. Setting shear pin 24 fixes the setting ring 23 and coupling ring 25. The top outer edge of coupling ring 25 abuts against the lower part of locking sleeve 22. The lower internal thread of lower coupling cap 26 connects to the middle external thread of lower connector 27.

[0036] Working principle or operation process:

[0037] 1. Setting the Packer: After lowering the packer to the designed depth in the well, pressure is applied to the tubing. Fluid enters the annulus between the central tube 6 and the rotary unsealing joint 4 through the upper fluid hole of the central tube 6, pushing the backwash piston 8 downward. The backwash piston 8 pushes the backwash piston seat 11 downward to compress the rubber sleeve 12. Simultaneously, fluid enters the hydraulic chamber between the central tube 6 and the upper cylinder 16 through the lower fluid hole of the central tube 6, and enters the hydraulic chamber between the lower central tube 17 and the lower cylinder 18 through the fluid hole of the lower central tube 17, pushing the upper cylinder 16 and the lower cylinder 18 upward synchronously. The upper cylinder 16 pushes the lower backwash sleeve 15 upward to compress the rubber sleeve 12. The rubber sleeve 12 expands under the upper and lower compression forces, sealing the inner wall of the casing; at this time, the backwash piston 8 reaches the outer periphery of the rubber sleeve bushing 14 and seals against it.

[0038] When the hydraulic cylinder 18 moves the locking sleeve 22 upward to lock the locking sleeve 22 with the locking ring 19, and the locking sleeve 22 pulls the setting ring 23 to break the setting shear pin 24, the setting is successful.

[0039] 2. Backwashing: During backwashing, liquid from the upper annulus enters the inner cavity of the upper backwash sleeve 7 through the backwash inlet hole 7a, pushing the backwash piston 8 upward. Then, the liquid flows downward along the annulus between the rubber sleeve bushing 14 and the central tube 6, flows out through the backwash outlet hole 15a of the lower backwash sleeve 15, and enters the annulus below the rubber sleeve, forming a backwashing channel.

[0040] III. Unsealing: When the packer needs to be unsealed and removed from the tubing after construction is completed, the following two unsealing methods can be used:

[0041] 1. Lifting and Unsealing Method: Lift the tubing string, which sequentially pulls the upper connector 1, the rotating unsealing connector 4, the upper backwash sleeve 7, and the backwash piston seat 11 upwards, releasing the upper support force on the rubber sleeve. Simultaneously, the tubing string sequentially pulls the upper connector 1, the rotating unsealing connector 4, the central tube 6, the lower central tube 17, and the lower connector 27 upwards. Since the locking ring 19 and the locking ring seat 21 are locked by the locking sleeve 22 after the packer is set, when the lower connector 27 moves upwards, the lifting and unsealing shear pin 20 is sheared, the locking fails, and the lower support force on the rubber sleeve is released. At this time, the rubber sleeve rebounds under its own elasticity and separates from the sleeve wall, allowing the tubing string to be lifted out.

[0042] 2. Rotary unsealing method: If lifting the tubing fails to unseal the packer, rotate the tubing forward, causing the upper connector 1 and the rotary unsealing connector 4 to rotate forward. Since the rotary unsealing connector 4 and the central tube 6 are connected by a reverse thread, which is equivalent to a screw mechanism, the central tube 6 moves downward, shears the rotary unsealing shear pin 3, and continues to move downward. At the same time, it pushes the lower central tube 17 and the lower connector 27 to move downward together. The lower connector 27 sequentially drives the locking ring 19, locking sleeve 22, lower liquid cylinder 18, upper liquid cylinder 16, lower backwash sleeve 15, and rubber sleeve bushing 14 to move downward. The upper and lower support forces of the rubber sleeve are released, and the rubber sleeve rebounds under its own elasticity, allowing the tubing to be lifted out.

[0043] The above description is merely a preferred embodiment of the present utility model, showing and describing the basic principles, main features, and advantages of the present utility model. It is not intended to limit the scope of patent protection of the present utility model. Those skilled in the art should understand that the present utility model is not limited to the above embodiments. In addition to the above embodiments, the present utility model may have other implementations without departing from the spirit and scope of the present utility model. Various changes and improvements to the present utility model are also possible. All technical solutions formed by equivalent substitutions or equivalent transformations fall within the scope of protection claimed by the present utility model. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents. Technical features not described in the present utility model can be implemented by or using existing technology, and will not be elaborated here.

Claims

1. A water-filled anti-jamming packer, comprising an upper connector (1), characterized in that, The lower end of the upper connector (1) is screwed with a rotary unsealing connector (4) and they are sealed to each other. The lower part of the rotary unsealing connector (4) is connected to the central tube (6) through a reverse internal thread. The upper cap (2) is screwed to the outer periphery of the upper end of the central tube (6) and is connected to the inner wall of the upper end of the rotary unsealing connector (4) through a rotary unsealing shear pin (3). A backwashing mechanism is connected below the rotary unsealing connector (4). A setting sealing mechanism is connected below the backwashing mechanism. A hydraulic drive mechanism is provided below the setting sealing mechanism. A lower connector (27) is connected below the hydraulic drive mechanism.

2. The anti-jamming water-filled packer according to claim 1, characterized in that: The backwashing mechanism includes an upper backwashing sleeve (7), a backwashing piston (8), and a backwashing piston seat (11). The upper backwashing sleeve (7) is screwed to the lower part of the rotary unsealing connector (4). The backwashing piston (8) is located in the inner cavity of the upper backwashing sleeve (7) and is sleeved on the outer periphery of the central tube (6). The upper end of the backwashing piston (8) is sealed to the central tube (6) and the upper backwashing sleeve (7) respectively. The lower part of the upper backwashing sleeve (7) is provided with a backwashing inlet hole (7a). The backwashing piston seat (11) is connected to the lower end of the upper backwashing sleeve (7).

3. The anti-jamming water-filled packer according to claim 2, characterized in that: The upper end of the backwash piston seat (11) is provided with a flared opening, and the lower end of the backwash piston (8) is fitted with a sealing ring (9) and pressed by a pressure ring (10). The outer conical surface of the sealing ring (9) matches the inner conical surface of the flared opening of the backwash piston seat (11).

4. The anti-jamming water-filled packer according to claim 2, characterized in that: The setting mechanism includes a rubber tube (12), a spacer ring (13), and a rubber tube bushing (14). The rubber tube bushing (14) is fitted around the outer periphery of the central tube (6) and there is a gap between it and the central tube (6). The rubber tube (12) is fitted around the outer periphery of the rubber tube bushing (14). Adjacent rubber tubes (12) are separated by spacer rings (13). The top rubber tube abuts against the bottom of the backwash piston seat (11).

5. The anti-jamming water-filled packer according to claim 4, characterized in that: The bottom rubber tube abuts against the top of the lower backwash sleeve (15), and the lower backwash sleeve (15) is provided with a backwash outlet hole (15a) in the middle; the lower inner circumference of the backwash piston (8) is provided with an annular space for the rubber tube bushing (14) to be inserted, and a sealing ring is embedded in the inner wall of the annular space.

6. The anti-jamming water-filled packer according to claim 5, characterized in that: The hydraulic drive mechanism includes an upper cylinder (16), a lower central tube (17), and a lower cylinder (18). The upper cylinder (16) is connected below the lower backwash sleeve (15) and its upper part is sealed to the outer wall of the central tube (6). The lower central tube (17) is connected to the lower end of the central tube (6), and the lower cylinder (18) is connected below the upper cylinder (16) and its upper part is sealed to the outer wall of the lower central tube (17). The central tube (6) has a through hole that communicates with the hydraulic chamber of the upper cylinder (16), and the lower central tube (17) has a through hole that communicates with the hydraulic chamber of the lower cylinder (18).

7. A water-filled anti-jamming packer according to claim 6, characterized in that: The lower connector (27) is connected to the lower end of the lower central tube (17). The outer wall of the upper large diameter section of the lower connector (27) is fitted with a sealing ring that seals the lower inner wall of the lower liquid cylinder (18).

8. A water-filled anti-jamming packer according to claim 7, characterized in that: A locking ring (19) is fitted below the middle step of the lower connector (27). The locking ring seat (21) is fixed to the outer periphery of the lower connector (27) and located below the locking ring (19) by the lifting release screw (20). The outer wall of the locking ring (19) is provided with external ratchet teeth. The lower section of the lower liquid cylinder (18) is connected to a locking sleeve (22). The inner wall of the locking sleeve (22) is provided with internal ratchet teeth.

9. A water-filled anti-jamming packer according to claim 8, characterized in that: The lower part of the lock sleeve (22) is connected to a setting ring (23), and the middle outer periphery of the lower connector (27) is provided with a merging ring (25). The setting shear pin (24) fixes the setting ring (23) and the merging ring (25) together. The top outer edge of the merging ring (25) abuts against the lower part of the lock sleeve (22), and the lower end internal thread of the lower merging cap (26) is connected to the middle external thread of the lower connector (27).

Images