A downhole packer and directional water injection integrated tool for water injection wells

Abstract

The application discloses a downhole pack-off and directional water injection integrated tool for water injection wells, and relates to the technical field of water injection tools for oil fields.The tool comprises an anchoring module, a sealing module and a water injection module, the anchoring module and the sealing module are connected in series, the sealing module is sleeved on the outer side of the water injection module, the sealing module comprises an outer tube and a middle rubber sleeve sleeved on the outer tube, the middle rubber sleeve is a fan-shaped rubber, and a water outlet hole is formed in the outer tube at the opening of the middle rubber sleeve; when the water outlet hole is communicated with the inner cavity of the water injection module, directional water injection can be carried out; the anchoring module comprises an upper joint, an upper sleeve, an upper core tube, an outer lock sleeve and a split lock sleeve, the sealing module comprises an outer tube and a lower connecting ring, and a compression ring, an upper rubber sleeve, a spacer ring, a middle rubber sleeve, a spacer ring and a lower rubber sleeve are sequentially and slidably sleeved on the outer tube from top to bottom; the tool can control the water injection direction, improve the permeability of the stratum in the specified direction of the oil well, and reduce the problems of "sudden advance" and "channeling flow" in the main oil driving channel direction.

Description

Technical Field

[0001] This invention relates to the field of oilfield water injection tools, specifically to an integrated tool for downhole isolation and directional water injection in water injection wells. Background Technology

[0002] In the mid-to-late stages of oilfield development in my country, formation energy decreases and crude oil viscosity increases, severely impacting crude oil production. To replenish formation flow, stratified water injection is one effective means to improve oil production efficiency. However, with increased water injection, the unevenness of formation water absorption profiles intensifies significantly. Considering the heterogeneity and complexity of formations and oil layers, in high-permeability oil layers, when the injected water volume greatly exceeds the produced fluid (i.e., a high injection-to-production ratio), water flooding of the oil layer is easily accelerated. After large-scale water flooding, water drive efficiency is greatly reduced, resulting in a situation where oil is simply washed with water. In medium-to-low permeability layers, due to the different permeabilities between oil reservoir layers, injected water tends to surge along the higher permeability layers, easily causing a sharp increase in water cut. This leads to problems such as "rushing" and "channeling" of injected water within the oil layer, resulting in a sharp increase in water cut and a sharp decrease in daily oil production, thereby slowing down the oil production rate of a single well and reducing the recovery rate of the block. When the water cut of an oil well reaches 98%, it means that the oil well has lost its exploitation value. Considering the varying permeability of the same permeable layer within the formation, injected water tends to surge along the high-permeability zone, forming the main oil-displacement channel. The water absorption index in this high-permeability layer continuously increases with the amount of injected water, making it more difficult for the injected water to displace crude oil in other directions, severely limiting the oil displacement area. Simultaneously, as the oil content in the main oil-displacement channel decreases, the water cut in the corresponding wells increases, leading to a significant reduction in recovery rate.

[0003] Chinese patent CN202220910839.9 discloses a downhole stratified water injection tool, including a pipe body. The outer surface of the pipe body is provided with four protective plates. Each protective plate has three clamping brackets installed on its outer surface. Each clamping bracket has a rolling shaft movably hinged inside. Each protective plate has three shock-absorbing springs installed on its inner wall. The end of each shock-absorbing spring away from the protective plate is fixedly connected to the outer surface of the pipe body. The outer surface of the pipe body has two sets of staggered liquid outlets. Two sets of flow guides are installed on the outer surface of the pipe body. Each set of flow guides is located outside the liquid outlet. This technical solution cannot achieve directional water injection and cannot improve the formation permeability in a specified direction of the oil well.

[0004] Therefore, increasing the formation water absorption index in the direction of non-primary oil displacement channels within the injection well and its well network is crucial for improving oil well recovery. Summary of the Invention

[0005] In order to improve the formation permeability in a specified direction of oil wells and reduce the problems of "rushing" and "cross-flow" in the direction of the main oil displacement channel, this invention provides an integrated tool for downhole isolation and directional water injection in water injection wells.

[0006] The technical solution of this invention is: an integrated tool for downhole sealing and directional water injection in a water injection well, comprising an anchoring module, a sealing module, and a water injection module. The anchoring module and the sealing module are connected in series, and the sealing module is fitted on the outside of the water injection module. The sealing module includes an outer tube and a middle rubber sleeve fitted on the outer tube. The middle rubber sleeve is a fan-shaped rubber, and a water outlet hole is opened on the outer tube corresponding to its opening. When the water outlet hole is connected to the inner cavity of the water injection module, directional water injection can be performed.

[0007] Preferably, the anchoring module includes an upper connector, an upper sleeve, an upper core tube, an outer locking sleeve, and a segmented locking sleeve. The upper core tube is fixedly connected to the lower end of the upper connector, and the upper part of the segmented locking sleeve is fitted onto the outside of the upper core tube, with the two connected by shear pins. The upper sleeve is connected to the outer locking sleeve, with the upper part of the upper sleeve slidingly and sealingly fitted onto the upper connector, and its lower part slidingly and sealingly fitted onto the upper core tube. The outer locking sleeve is slidably fitted onto the outside of the segmented locking sleeve. The upper core tube has a liquid inlet hole that communicates with the annular space of the upper core tube of the upper sleeve. The lower part of the segmented locking sleeve is evenly divided into multiple locking claws along the circumference. The locking claws cooperate with the outer locking sleeve to realize unidirectional movement of the upper sleeve and the outer locking sleeve, and the outer locking sleeve has a liquid inlet hole.

[0008] Preferably, the anchoring module further includes an upper piston, the upper sleeve, the upper piston and the outer locking sleeve are connected in series, the lower part of the upper piston is slidably sealed on the upper core tube, an annular seat is provided on the outer wall of the upper core tube between the lower part of the upper sleeve and the lower part of the upper piston, and the upper core tube is also provided with a liquid inlet hole that communicates with the annular space of the upper piston and the upper core tube.

[0009] Preferably, the outer wall of the locking claw is provided with a downwardly inclined first oblique tooth, and the inner wall of the outer locking sleeve is provided with an upwardly inclined second oblique tooth that matches the first oblique tooth.

[0010] Preferably, the locking claw has 12 claws.

[0011] Preferably, the sealing module includes an outer tube and a lower connecting ring. The lower end of the outer tube is provided with an outer step seat and is fixedly connected to the lower connecting ring. A pressure ring, an upper rubber cylinder, a spacer ring, a middle rubber cylinder, a spacer ring and a lower rubber cylinder are slidably sleeved on the outer tube from top to bottom. The lower end face of the lower rubber cylinder contacts the outer step seat, and the pressure ring contacts the lower end face of the outer locking sleeve.

[0012] Preferably, the middle rubber cylinder is a fan-shaped rubber with a circumferential angle of 270°, and retaining rings are arranged at both ends of its circumferential direction.

[0013] Preferably, the water injection module includes an opening ring and a lower core tube. The upper end of the lower core tube is fixedly connected to the lower end of the upper core tube, and the lower end is connected to a lower connector. The lower connector is fixedly connected to the lower connecting ring through a lower sleeve. The opening ring is slidably disposed in the annular space of the outer tube of the lower core tube. Its upper end is fixedly connected to an outer locking sleeve, and its interior is provided with a limiting groove for accommodating the outer tube. Its lower end is provided with a water outlet. The lower core tube is provided with a water outlet hole that is collinear with the water outlet hole of the outer tube.

[0014] Compared with the prior art, the present invention has the following advantages: This tool can control the direction of water injection, improve the formation permeability in a specified direction of the oil well, reduce the problems of "rushing" and "crossing" in the direction of the main oil displacement channel, and further improve the degree of crude oil displacement in different directions within the well network of water injection wells. This tool has a simple structure, is easy to operate, has low cost, is universally applicable, and is easy to mass-produce. It provides a design method for designing downhole directional water injection technology for high water cut water injection wells that conform to actual conditions. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a structural schematic diagram of the anchoring module; Figure 3 This is a schematic diagram of the sealing module. Figure 4 This is a schematic diagram of the water injection module.

[0016] In the diagram: 1. Upper connector, 2. Upper sleeve, 3. Upper core tube, 4. Upper piston, 5. Outer locking sleeve, 6. Split locking sleeve, 7. Opening ring, 701. Outlet, 8. Pressure ring, 9. Outer tube, 901. Outer step seat, 10. Upper rubber sleeve, 11. Spacer ring, 12. Middle rubber sleeve, 13. Retaining ring, 14. Lower core tube, 15. Lower connecting ring, 16. Lower sleeve, 17. Lower rubber sleeve, 18. Lower connector. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments. Example 1

[0018] Reference Figure 1-4 As shown, a downhole sealing-directional water injection integrated tool for water injection wells includes an anchoring module, a sealing module, and a water injection module. The anchoring module and the sealing module are connected in series, and the sealing module is fitted on the outside of the water injection module. The sealing module includes an outer tube 9 and a middle rubber cylinder 12 fitted on the outer tube 9. The middle rubber cylinder 12 is a fan-shaped rubber, and a water outlet hole is opened on the outer tube 9 corresponding to its opening. When the water outlet hole is connected to the inner cavity of the water injection module, directional water injection can be performed.

[0019] The anchoring module includes an upper connector 1, an upper sleeve 2, an upper core tube 3, an outer locking sleeve 5, and a split locking sleeve 6. The upper core tube 3 is fixedly connected to the lower end of the upper connector 1. The upper part of the split locking sleeve 6 is fitted onto the outside of the upper core tube 3, and the two are connected by shear pins. The upper sleeve 2 is connected to the outer locking sleeve 5. The upper part of the upper sleeve 2 is slidably and sealingly fitted onto the upper connector 1, and its lower part is slidably and sealingly fitted onto the upper core tube 3. The outer locking sleeve 5 is slidably fitted onto the outside of the split locking sleeve 6. The upper core tube 3 has a liquid inlet hole that communicates with the annular space of the upper core tube 3 of the upper sleeve 2. The lower part of the split locking sleeve 6 is evenly divided into multiple locking claws along the circumference. The locking claws cooperate with the outer locking sleeve 5 to realize unidirectional movement of the upper sleeve 2 and the outer locking sleeve 5. The outer locking sleeve 5 is also provided with a liquid inlet hole.

[0020] The sealing module includes an outer tube 9 and a lower connecting ring 15. The lower end of the outer tube 9 is provided with an outer step seat 901 and is fixedly connected to the lower connecting ring 15. The outer tube 9 is slidably fitted with a pressure ring 8, an upper rubber cylinder 10, a spacer ring 11, a middle rubber cylinder 12, a spacer ring 11, and a lower rubber cylinder 17 from top to bottom. The lower end face of the lower rubber cylinder 17 contacts the outer step seat 901, and the pressure ring 8 contacts the lower end face of the outer locking sleeve 5.

[0021] The water injection module includes an opening ring 7 and a lower core tube 14. The upper end of the lower core tube 14 is fixedly connected to the lower end of the upper core tube 3, and the lower end is connected to a lower connector 18. The lower connector 18 is fixedly connected to the lower connecting ring 15 through a lower sleeve 16. The opening ring 7 is slidably disposed in the annular space of the outer tube 9 of the lower core tube 14. Its upper end is fixedly connected to the outer locking sleeve 5. It has a limiting groove inside for accommodating the outer tube 9. Its lower end has a water outlet 701. The lower core tube 14 has a water outlet hole that is collinear with the water outlet hole of the outer tube 9.

[0022] During operation, the tool is lowered to the perforation section, and liquid pressure is applied through the oil pipe. The liquid enters the annulus of the upper sleeve 2 and the upper core tube 3 through the inlet hole of the upper core tube 3. Under the action of liquid pressure, the upper sleeve 2 pushes the outer locking sleeve 5 and the opening ring 7 downward, pushing the pressure ring 8 to compress the upper rubber sleeve 10, the middle rubber sleeve 12, and the lower rubber sleeve 17, causing them to expand and seal the external annulus. At the same time, the outer locking sleeve 5 and the split locking sleeve 6 complete the engagement, keeping the sealing module in the set-sealed state. In addition, the opening ring 7 moves downward, and the internal water outlet 701 coincides with the water outlet of the lower core tube 14 and the outer tube 9, thereby establishing a water injection channel, followed by directional water injection operation. After the water injection operation is completed, liquid pressure is applied from the annulus between the casing and the oil pipe. The liquid pushes the upper sleeve 2 upward through the liquid inlet of the outer locking sleeve 5, and the shear pin drives the split locking sleeve 6 and the outer locking sleeve 5 to move upward synchronously, thereby driving the opening ring 7 to move upward, closing the water outlet, and the sealing element rebounds, completing the unsealing operation of this tool.

[0023] This tool can control the direction of water injection, improve the formation permeability in a specified direction of the oil well, reduce the problems of "rushing" and "crossing" in the direction of the main oil displacement channel, and further improve the degree of crude oil displacement in different directions within the well network of water injection wells. This tool has a simple structure, is easy to operate, has low cost, is universally applicable, and is easy to mass-produce. It provides a design method for designing downhole directional water injection technology for high water cut water injection wells that conform to actual conditions. Example 2

[0024] As a preferred embodiment of the present invention, this embodiment adds an upper piston 4 based on embodiment one, specifically: The anchoring module in this embodiment also includes an upper piston 4, an upper sleeve 2, an upper piston 4 and an outer locking sleeve 5 connected in series. The lower part of the upper piston 4 is slidably sealed on the upper core tube 3. An annular seat is provided on the outer wall of the upper core tube 3 between the lower part of the upper sleeve 2 and the lower part of the upper piston 4. The upper core tube 3 is also provided with a liquid inlet hole that communicates with the annular space of the upper piston 4 and the upper core tube 3.

[0025] During setting, liquid pressure is applied from the oil pipe. The liquid enters the annulus of the upper sleeve 2 and the upper core tube 3, as well as the annulus of the upper piston 4 and the upper core tube 3, through the inlet holes at the upper and lower ends of the upper core tube 3. The upper sleeve 2 and the upper piston 4 together push the outer locking sleeve 5 downward.

[0026] This embodiment uses a two-stage piston for force amplification, ensuring the smooth progress of the setting operation and increasing the setting speed. Example 3

[0027] As a preferred embodiment of the present invention, this embodiment optimizes the structure of the outer locking sleeve 5 and the split locking sleeve 6 based on Embodiment 1, specifically as follows: In this embodiment, the outer wall of the locking claw is provided with a downwardly inclined first helical tooth, and the inner wall of the outer locking sleeve 5 is provided with an upwardly inclined second helical tooth that matches the first helical tooth. With the cooperation of the first and second helical teeth, the outer locking sleeve 5 can only move downward relative to the split locking sleeve 6. Example 4

[0028] As a preferred embodiment of the present invention, this embodiment limits the number of locking claws based on Embodiment 1, specifically as follows: In this embodiment, the split locking sleeve 6 has 12 locking claws. Example 5

[0029] As a preferred embodiment of the present invention, this embodiment defines the structure of the intermediate rubber tube 12 based on Embodiment 1, specifically as follows: In this embodiment, the middle rubber cylinder 12 is a fan-shaped rubber with a circumferential angle of 270°, and retaining rings 13 are arranged at both ends of its circumferential direction.

[0030] This invention is not limited to the embodiments described above. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this invention, and the changed content still falls within the protection scope of this invention.

Claims

1. A tool for integrated downhole isolation and directional water injection in a water injection well, characterized in that: It includes an anchoring module, a sealing module, and a water injection module. The anchoring module and the sealing module are connected in series. The sealing module is fitted on the outside of the water injection module. The sealing module includes an outer tube and a middle rubber cylinder fitted on the outer tube. The middle rubber cylinder is a fan-shaped rubber, and a water outlet hole is opened on the outer tube corresponding to its opening. When the water outlet hole is connected to the inner cavity of the water injection module, directional water injection can be performed.

2. The integrated downhole isolation-directional water injection tool for water injection wells according to claim 1, characterized in that: The anchoring module includes an upper connector, an upper sleeve, an upper core tube, an outer locking sleeve, and a segmented locking sleeve. The upper core tube is fixedly connected to the lower end of the upper connector, and the upper part of the segmented locking sleeve is fitted onto the outside of the upper core tube, with the two connected by shear pins. The upper sleeve is connected to the outer locking sleeve, with the upper part of the upper sleeve slidingly and sealingly fitted onto the upper connector, and the lower part slidingly and sealingly fitted onto the upper core tube. The outer locking sleeve is slidably fitted onto the outside of the segmented locking sleeve. The upper core tube has a liquid inlet hole that communicates with the annular space of the upper core tube of the upper sleeve. The lower part of the segmented locking sleeve is evenly divided into multiple locking claws along the circumference. The locking claws cooperate with the outer locking sleeve to realize unidirectional movement of the upper sleeve and the outer locking sleeve, and the outer locking sleeve has a liquid inlet hole.

3. The integrated downhole isolation-directional water injection tool for water injection wells according to claim 2, characterized in that: The anchoring module also includes an upper piston. The upper sleeve, the upper piston and the outer locking sleeve are connected in series. The lower part of the upper piston is slidably sealed on the upper core tube. An annular seat is provided on the outer wall of the upper core tube between the lower part of the upper sleeve and the lower part of the upper piston. The upper core tube is also provided with a liquid inlet hole that communicates with the annular space of the upper core tube of the upper piston.

4. The integrated downhole isolation-directional water injection tool for water injection wells according to claim 2, characterized in that: The outer wall of the locking claw is provided with a first inclined tooth that slopes downward, and the inner wall of the outer locking sleeve is provided with a second inclined tooth that slopes upward and matches the first inclined tooth.

5. The integrated downhole isolation-directional water injection tool for water injection wells according to claim 2, characterized in that: The locking claw has 12 claws.

6. The integrated downhole isolation-directional water injection tool for water injection wells according to claim 2, characterized in that: The sealing module includes an outer tube and a lower connecting ring. The lower end of the outer tube is provided with an outer step seat and is fixedly connected to the lower connecting ring. A pressure ring, an upper rubber cylinder, a spacer ring, a middle rubber cylinder, a spacer ring and a lower rubber cylinder are slidably sleeved on the outer tube from top to bottom. The lower end face of the lower rubber cylinder contacts the outer step seat, and the pressure ring contacts the lower end face of the outer locking sleeve.

7. The integrated downhole isolation-directional water injection tool for water injection wells according to claim 6, characterized in that: The middle rubber cylinder is a fan-shaped rubber with a circumferential angle of 270°, and retaining rings are arranged at both ends of its circumferential direction.

8. The integrated downhole isolation-directional water injection tool for water injection wells according to claim 6, characterized in that: The water injection module includes an opening ring and a lower core tube. The upper end of the lower core tube is fixedly connected to the lower end of the upper core tube, and the lower end is connected to a lower connector. The lower connector is fixedly connected to the lower connecting ring through a lower sleeve. The opening ring is slidably disposed in the annular space of the outer tube of the lower core tube. Its upper end is fixedly connected to an outer locking sleeve, and its interior is provided with a limiting groove for accommodating the outer tube. Its lower end is provided with a water outlet. The lower core tube is provided with a water outlet hole that is collinear with the water outlet hole of the outer tube.

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