Water injection packer reliable in deblocking

Abstract

The invention discloses a water injection packer reliable in deblocking, and relates to the technical field of oil field downhole tools. The piston is provided with a stepped hole outside the through hole, the diameter of the stepped hole is enlarged, a setting column is connected in the through hole in a clearance fit mode, the setting column is provided with a stepped shaft in the stepped hole, the stepped shaft is in clearance fit with the stepped hole, a compression spring A is arranged between the stepped shaft and the stepped hole, a compression spring B is arranged between the stepped shaft and the cylinder sleeve, and a setting hole is formed in the position, below the through hole, of the central pipe. The packer has the beneficial effects that the compression spring A and the compression spring B are arranged on the two sides of the step shaft of the setting column, so that the setting column can be inserted into the setting hole for setting, the setting column pops out of the setting hole for unsetting after the upper connector is detached, and when the rubber sleeve cannot be reset, forced unsetting can be achieved by lifting an unsetting tool upwards, and meanwhile, the packer can be lifted out of a shaft for recycling.

Description

Technical Field

[0001] The invention relates to the technical field of oilfield downhole tools, in particular to a water injection packer with reliable unsealing. Background Art

[0002] A packer is an elastic sealing element that seals the annular space between it and the casing and isolates the production layer to control the fluid production. It is widely used in drilling, cementing, testing, completion and downhole oil operations. When the existing packer is unsealed, the unsealing shear pins are cut off by the unsealing lifting tool, that is, the slips and the rubber tube lose their axial limit, thereby resetting the slips and the rubber tube and separating the entire packer from the wellbore. However, due to the complex downhole environment, especially high-temperature water injection wells, the high-temperature liquid causes the rubber tube to be permanently deformed and cannot be reset, and the packer cannot be removed from the wellbore, and the wellbore can only be dredged by drilling and other means. Summary of the invention

[0003] In order to solve the problem that the existing water injection well packer in the oil field is easy to get stuck, the present invention provides a water injection packer with reliable unblocking.

[0004] The technical scheme provided by the present invention is: a water injection packer with reliable unsealing, comprising an upper joint and a lower joint, wherein the upper joint is processed with a female thread of an oil pipe, and the lower side of the lower joint is processed with a male thread of an oil pipe, the lower part of the upper joint is connected to a center pipe through a thread and a sealing ring, and the lower part of the center pipe is connected to the lower joint through a pin and a sealing ring, a cylinder sleeve is extended downward from the outer side of the upper joint, a piston is installed between the cylinder sleeve and the center pipe, the piston is matched with the clearance between the cylinder sleeve and the center pipe through a sealing ring, a liquid inlet hole is opened at the part of the center pipe above the sealing ring of the piston, and an upper retaining ring, a rubber cylinder, a lower retaining ring and a slip are sequentially sleeved on the lower side of the piston, wherein the upper retaining ring, the lower retaining ring and the rubber cylinder are fixedly connected by vulcanization, the lower retaining ring is connected to the slip through a limit plate, the slip is hinged to the limit plate through a pin shaft A, a long hole is opened on the lower retaining ring, the limit plate is hinged to the long hole through a pin shaft B, the slip is connected to the lower joint through a dovetail groove guide rail, and the motion trajectory of the dovetail groove guide rail is: the slip moves outward while descending; A transverse through hole is opened on the piston, and a step hole with an enlarged diameter is opened on the outside of the through hole. The through hole is connected with a sealing column with clearance fit. The sealing column is provided with a step shaft in the step hole. The step shaft and the step hole are clearance fit. A compression spring A is provided between the step shaft and the step hole, and a compression spring B is provided between the step shaft and the cylinder liner. A sealing hole is opened on the center tube below the through hole.

[0005] It also includes an unsealing tool, wherein the upper part of the unsealing tool is processed with a female oil pipe thread, the lower part of the unsealing tool is processed with a female unsealing thread, and the outer circle of the upper retaining ring is processed with a male unsealing thread.

[0006] A compression spring C is provided between the rubber cylinder and the center tube.

[0007] The outer side of the slips is processed with transverse annular teeth and vertical strip teeth.

[0008] The outer circular thread of the lower sub is connected to the limit sleeve, the upper part of the limit sleeve abuts against the lower end of the slips, and the limit sleeve is made of soluble metal.

[0009] The elastic stiffness of compression spring A is less than that of compression spring B.

[0010] The beneficial effects of the present invention are as follows: By arranging compression spring A and compression spring B on both sides of the stepped shaft of the setting column, a setting and releasing control system is formed at the piston part. After the pressure of the pipe string increases and the piston descends, the setting column can be inserted into the setting hole for setting. After the upper sub is removed, the setting column pops out of the setting hole for releasing. When the rubber barrel cannot be reset, the releasing tool can be lifted to force the release, and at the same time, the packer can be lifted out of the wellbore for reuse. Description of the Drawings

[0011] Att Figure 1 is the structural schematic diagram of the present invention; Att Figure 2 is the enlarged view at A of Att Figure 1 of; Att Figure 3 is Att Figure 1 of the enlarged view at B; Att Figure 4 is the structural schematic diagram after setting; Att Figure 5 is the structural schematic diagram after the upper sub is disassembled; Att Figure 6 is the structural schematic diagram after releasing; Att Figure 7 is the structural schematic diagram of using the releasing tool to force the release; Att Figure 8 is the structural schematic diagram of the releasing tool.

[0012] In the figure, 1 - upper sub, 101 - cylinder sleeve, 2 - lower sub, 3 - central tube, 4 - piston, 401 - through hole, 402 - stepped hole, 5 - liquid inlet hole, 6 - upper retaining ring, 601 - releasing male thread, 7 - rubber barrel, 8 - lower retaining ring, 801 - long hole, 9 - slips, 901 - annular teeth, 902 - strip teeth, 10 - limit sleeve, 11 - limit piece, 12 - pin shaft A, 13 - pin shaft B, 14 - setting hole, 15 - dovetail groove guide rail, 16 - setting column, 1601 - stepped shaft, 17 - compression spring A, 18 - compression spring B, 19 - compression spring C, 20 - pin, 21 - releasing tool, 2101 - releasing female thread. Detailed Implementation Manner

[0013] Such as Figures 1 to 8As shown, a water injection packer with reliable unsealing comprises an upper joint 1 and a lower joint 2. The upper joint 1 is processed with a female thread of an oil pipe, and the lower side of the lower joint 2 is processed with a male thread of an oil pipe. The lower part of the upper joint 1 is connected to a center pipe 3 through a thread and a sealing ring. The lower part of the center pipe 3 is connected to the lower joint 2 through a pin 20 and a sealing ring. A cylinder sleeve 101 extends downward from the outer side of the upper joint 1. A piston 4 is installed between the cylinder sleeve 101 and the center pipe 3. The piston 4 is in clearance fit with the cylinder sleeve 101 and the center pipe 3 through a sealing ring. The center pipe 3 is located above the sealing ring of the piston 4. A liquid inlet hole 5 is provided, and an upper retaining ring 6, a rubber cylinder 7, a lower retaining ring 8 and a slip 9 are sequentially sleeved on the lower side of the piston 4, wherein the upper retaining ring 6, the lower retaining ring 8 and the rubber cylinder 7 are fixedly connected by vulcanization, the lower retaining ring 8 is connected to the slip 9 through a limit plate 11, the slip 9 is hingedly connected to the limit plate 11 through a pin A12, a long hole 801 is provided on the lower retaining ring 8, the limit plate 11 is hingedly connected to the long hole 801 through a pin B13, the slip 9 is connected to the lower joint 2 through a dovetail groove guide rail 15, and the motion trajectory of the dovetail groove guide rail 15 is: the slip 9 moves outward while descending; A transverse through hole 404 is formed on the piston 4, and a step hole 402 with an enlarged diameter is formed on the outer side of the through hole 401. The through hole 401 is connected with a sealing column 16 with a clearance fit. The sealing column 16 is provided with a step shaft 1601 in the step hole 402. The step shaft 1601 is clearance-fitted with the step hole 402. A compression spring A17 is provided between the step shaft 1601 and the step hole 402, and a compression spring B18 is provided between the step shaft 1601 and the cylinder liner 101. A sealing hole 14 is formed on the center tube 3 below the through hole 401.

[0014] It also includes an unsealing tool 21 , the upper part of the unsealing tool 21 is processed with a female oil pipe thread, the lower part of the unsealing tool is processed with an unsealing female thread 2101 , and the outer circle of the upper retaining ring 6 is processed with an unsealing male thread 601 .

[0015] A compression spring C19 is provided between the rubber cylinder 7 and the central tube 3 to facilitate the resetting of the rubber cylinder 7 .

[0016] The outer side of the slip 9 is processed with a transverse annular tooth 901 and a vertical strip tooth 902, which not only serves to suspend the weight of the packer, but also prevents the lower part of the packer from rotating when the upper joint 1 is disassembled.

[0017] The outer circle of the lower joint 2 is connected to the limit sleeve 10 with a thread. The upper part of the limit sleeve 10 is pressed against the lower end of the slip 9. The limit sleeve 10 is made of soluble metal. The limit sleeve 10 is used for axial limitation of the slip 9 to prevent the slip 9 from malfunctioning and descending during the process of going down into the well, causing the well to be stuck. The limit sleeve 10 is dissolved under the action of the liquid in the wellbore and then sealed.

[0018] The elastic stiffness of the compression spring A17 is smaller than the elastic stiffness of the compression spring B18.

[0019] After the packer is lowered to the set position, the pressure in the pipe column increases, the liquid pressure drives the piston 4 to descend, and the setting column 16 is inserted into the setting hole 14 under the action of the compression spring B18 to complete the setting. At this time, the rubber cylinder 7 expands and seals with the casing, and the slip 9 descends and is stuck on the inner wall of the casing. When unsealing, the pipe column is rotated to remove the upper joint 1. At this time, the compression spring B18 loses its compression surface and loses its function. The setting column 16 pops out of the setting hole 14 under the action of the compression spring A17 to achieve unsealing. The pipe column is connected to the unsealing tool 21, and the unsealing tool 21 is The unsealing female thread 2101 is connected to the unsealing male thread 601 of the upper retaining ring 6. The rotating unsealing tool 21 can remove the packer and the lower pipe string and lift them out of the wellbore. When the rubber tube 7 is permanently deformed and cannot be reset, the unsealing tool 21 can be lifted up. Since the cava 9 is connected to the lower joint 2 through the dovetail groove guide rail 15, when the inner side of the cava 9 is attached to the central pipe 3, it cannot rise anymore. Since the rubber tube 7 is fixedly connected to the upper retaining ring 6 and the lower retaining ring 8 by vulcanization, the lifting of the unsealing tool 21 can force the rubber tube 7 to be pulled back to its original shape, and the unsealing is reliable.

[0020] By arranging the compression spring A17 and the compression spring B18 on both sides of the step shaft of the sealing column 16, a sealing and unsealing control system is formed at the piston 4. After the tubing booster piston descends, the sealing column 16 can be inserted into the sealing hole 14 for sealing. After the upper joint 1 is removed, the sealing column 16 pops out of the sealing hole 14 for unsealing. When the rubber cylinder 7 cannot be reset, the lifting unsealing tool 21 can be forced to unseal, and the packer can be lifted out of the wellbore for reuse.

Claims

1. A water injection packer with reliable unsealing, comprising an upper joint (1) and a lower joint (2), characterized in that: The upper part of the upper joint (1) is processed with a female thread of the oil pipe, and the lower side of the lower joint (2) is processed with a male thread of the oil pipe. The lower part of the upper joint (1) is connected to the center pipe (3) through threads and a sealing ring, and the lower part of the center pipe (3) is connected to the lower joint (2) through a pin (20) and a sealing ring. A cylinder sleeve (101) extends downward from the outer side of the upper joint (1), and a piston (4) is installed between the cylinder sleeve (101) and the center pipe (3). The piston (4) is clearance-matched with the cylinder sleeve (101) and the center pipe (3) through a sealing ring. The center pipe (3) is provided with a liquid inlet hole (5) at a position above the sealing ring of the piston (4), and the center pipe (3) is provided with a liquid inlet hole (5) at the lower side of the piston (4). An upper retaining ring (6), a rubber tube (7), a lower retaining ring (8) and a slip (9) are sequentially sleeved, wherein the upper retaining ring (6), the lower retaining ring (8) and the rubber tube (7) are fixedly connected by vulcanization, the lower retaining ring (8) is connected to the slip (9) via a limit plate (11), the slip (9) is hingedly connected to the limit plate (11) via a pin shaft A (12), a long hole (801) is opened on the lower retaining ring (8), the limit plate (11) is hingedly connected to the long hole (801) via a pin shaft B (13), the slip (9) is connected to the lower joint (2) via a dovetail groove guide rail (15), and the movement trajectory of the dovetail groove guide rail (15) is: the slip (9) moves outward while descending; The piston (4) is provided with a through hole (404) extending transversely therethrough. The piston (4) is provided with a stepped hole (402) with an enlarged diameter on the outside of the through hole (401). The through hole (401) is connected to a setting column (16) with a clearance fit. The setting column (16) is provided with a stepped shaft (1601) in the stepped hole (402). The stepped shaft (1601) and the stepped hole (402) are clearance fit. A compression spring A (17) is provided between the stepped shaft (1601) and the stepped hole (402). A compression spring B (18) is provided between the stepped shaft (1601) and the cylinder sleeve (101). The center tube (3) is provided with a setting hole (14) at a position below the through hole (401).

2. A water injection packer with reliable unsealing according to claim 1, characterized in that: It also includes an unsealing tool (21), the upper part of the unsealing tool (21) is processed with a female oil pipe thread, the lower part of the unsealing tool is processed with an unsealing female thread (2101), and the outer circle of the upper retaining ring (6) is processed with an unsealing male thread (601).

3. A water injection packer with reliable unsealing according to claim 1, characterized in that: A compression spring C (19) is provided between the rubber cylinder (7) and the central tube (3).

4. A water injection packer with reliable unsealing according to claim 1, characterized in that: The outer side of the slip (9) is processed with transverse annular teeth (901) and vertical bar teeth (902).

5. The water injection packer with reliable unsealing according to claim 1, characterized in that: The outer circle of the lower joint (2) is connected to the limiting sleeve (10) by a threaded connection, the upper part of the limiting sleeve (10) is pressed against the lower end of the slip (9), and the limiting sleeve (10) is made of soluble metal.

6. The water injection packer with reliable unsealing according to claim 1, characterized in that: The elastic stiffness of the compression spring A (17) is smaller than the elastic stiffness of the compression spring B (18).

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