Re-sealable large channel packer and integrated water injection tool

Abstract

A reusable, large-channel integrated water injection tool, belonging to the field of oilfield development technology, includes an upper connector, a guide body sleeve screwed to the upper connector, a main body screwed to the guide body sleeve, a guide body fixed to the left end face of the main body, a main body sleeve screwed to the main body, and an inner connecting sleeve screwed to the main body. This tool integrates the functions of a water injection packer and a water distributor into a single, linked mechanism. During water injection, the tool sets; during backwashing, the tool unseals. It can be repeatedly set and unsealed. During backwashing, the packer sleeve is in its initial, unexpanded state, resulting in a large and effective well-washing channel. Because there is no opening and closing of the well-washing piston channel, the possibility of piston failure is reduced, significantly extending the cycle of the water well tubing and saving operating costs. During tubing tripping operations, backwashing restores the tool to its initial state, eliminating difficulties in tubing unsealing, and ensuring safety, environmental friendliness, and reliability. Therefore, it has excellent application prospects in oilfields.

Description

Technical Field

[0001] This utility model belongs to the field of oilfield development technology, and specifically relates to a reusable, integrated water injection tool for sealing and sealing large channels. Background Technology

[0002] Currently, oilfield development primarily employs stratified water injection or stratified polymer injection displacement production methods. The main tool for achieving stratified injection (water or polymer injection) is a stratified injection string composed of multiple water injection packers and multiple distributors. Among these, compression packers and expansion packers are commonly used, while eccentric and concentric distributors are frequently used. The packers and distributors are rationally combined according to the stratified development plan to ensure the quality requirements of stratified injection. However, the stratified string using this tool combination has the following shortcomings during use: First, the quality during the injection process is difficult to control. Because contaminants in the injected fluid often block or narrow the injection channels, affecting the injection quality, backwashing is frequently required to clean the channel surface and the inner wall of the tubing. First, conventional compression packers have several drawbacks. First, they present challenges in maintaining proper flow. The first is the limited flow channel, leading to poor backwashing quality. Prolonged downhole use can cause piston failure, necessitating rework. Second, the sealing effect of the tubing string is difficult to guarantee. While using an expansion packer combined with a distributor can enlarge the flow channel and improve backwashing quality, the sealing quality is poor when the injection pressure differential is small, affecting injection quality. Third, the operation of tiered water injection tubing is difficult, and well control and environmental protection pressures are high. Water injection tubing composed of multiple compression packers often cannot be retrieved normally due to packer desealing difficulties, requiring major repairs. Furthermore, the inability of conventional distributor nozzles to control the flow at the wellhead during tiered water injection tubing operation creates difficulties for well control and environmental protection, significantly increasing production costs. Summary of the Invention

[0003] The purpose of this invention is to provide a reusable, integrated water injection tool for sealing large channels, in order to solve the aforementioned problems existing in the current layered water injection tubing and tools.

[0004] The technical solution adopted by this utility model is: a reusable sealing and sealing integrated water injection tool for large channels. The key technical point is that a reusable sealing and sealing integrated water injection tool for large channels includes an upper connector, a guide body sleeve screwed to the upper connector, a main body screwed to the guide body sleeve, a guide body fixed on the left end face of the main body, a main body sleeve screwed to the main body, an inner connecting sleeve screwed to the main body, and an upper central tube screwed to the inner connecting sleeve. The guide head is inserted into the upper central tube and fixed. The retaining spring is screwed onto the upper central tube. The injection valve and the injection valve spring are both sleeved on the outside of the upper central tube and, under the action of the injection valve spring, make the injection valve and the main body sleeve tightly contact to form a seal A.

[0005] The piston sleeve is placed outside the upper central tube and contacts the inner connecting sleeve. The open snap ring is installed in the groove on the inner connecting sleeve and protrudes from the groove by a certain distance. The outer connecting sleeve is screwed to the outer sleeve of the main body. The piston sleeve is placed outside the upper central tube and inserted into the inner connecting sleeve, moving left and right under the action of internal or external pressure. The valve seat is screwed to the outer connecting sleeve. The lower central tube and the upper protective sleeve are screwed to the valve seat respectively. The vulcanized rubber sleeve is placed outside the lower central tube and screwed to the upper protective sleeve. The lower protective sleeve is screwed to the vulcanized rubber sleeve. The lower connector is screwed to the lower protective sleeve. The shear pin sleeve is placed outside the lower connector and screwed to the lower protective sleeve. The shear pin screwed to the shear pin sleeve is inserted into the annular groove of the lower connector and fixed.

[0006] In the above scheme, the sealing piston is limited to move to its left by an open snap ring.

[0007] In the above scheme, a gap is left between the inside of the vulcanized rubber cylinder and the outside of the lower middle tube for liquid to pass through.

[0008] In the above scheme, when the pressure in the oil pipe exceeds the pressure that the piston's elastic claw can withstand, the elastic claw is pushed outward by the upper boss of the injection valve and moves under the action of pressure until it contacts the retaining ring and is limited. When the piston's elastic claw moves to the diameter change point of the injection valve, it will spring back to the initial state.

[0009] In the above scheme, after the piston moves, it contacts the valve core and pushes the valve core to move in order to open the seal B.

[0010] The beneficial effects of this utility model are as follows: This reusable, large-channel integrated water injection tool integrates the water injection packer and the injector into a single, linked structure. During normal injection, the pressure control valve first expands and seals the packer and casing. When the injection pressure reaches a certain value, the injection channel opens for normal injection production. At this time, the packer remains sealed under the operation of the pressure control valve. When backwashing is required, the backwash fluid is introduced into the annulus via a reverse flow at the wellhead. At this time, the pressure in the annulus is higher than the pressure inside the tubing. When the injection pressure reaches a certain value, the backwash piston moves and opens the sealing pressure channel of the packer. The packer sleeve returns to its unreleased state. The reusable, large-channel integrated water injection tool is then unsealed step by step from top to bottom until the last stage is unsealed and connected to the annulus and tubing for well washing. Since the flow channel in the annulus is much larger than that of a conventional packer, the well washing quality and efficiency can be greatly improved. After backwashing is completed, the tubing is injected with water normally. At this time, the water injection tool with the large channel sealing and matching integrated water injection tool can be re-set and sealed. The water injection channel is in the closed position, and the layered water injection string is in a sealed state. The tool can then be re-set and injected normally. Repeating the above actions can complete the backwashing, setting, and water injection functions. When it is necessary to perform layered water injection string tripping operations, the tool can be unsealed from top to bottom through the backwashing well in the annulus and casing, and the string can be tripped. The entire string can be kept in a sealed state without the need for water nozzle construction, making the tripping of the string safer, more environmentally friendly, and more reliable.

[0011] This tool sets during water injection and unseals during backwashing; it can be repeatedly set and unsealed. During backwashing, the packer sleeve is in its initial, unexpanded state, providing a large and effective washing channel. Because there is no opening and closing of the washing piston channel, the possibility of piston failure is reduced, significantly extending the cycle of the water well tubing and saving operating costs. During tubing tripping, backwashing restores the tool to its initial state, eliminating difficulties in tubing unsealing, ensuring safety, environmental friendliness, and reliability. Therefore, it has excellent application prospects in oilfields. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in 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 from these drawings without creative effort.

[0013] Figure 1 This is a structural schematic diagram of the reusable sealing and assembly integrated water injection tool for large channels in this embodiment of the present invention;

[0014] Figure 2 for Figure 1Sectional view along axis AA;

[0015] Figure 3 for Figure 1 Enlarged view of a section at point C;

[0016] Figure 4 This is a partial enlarged view of part D of the integrated sealing and fitting tool in this embodiment of the present invention;

[0017] Figure 5 This is a schematic diagram of the elastic gripper structure in an embodiment of the present utility model;

[0018] Figure 6 This is a schematic diagram of the boss structure in an embodiment of the present utility model;

[0019] Figure 7 This is a perspective view of the injection valve structure in an embodiment of this utility model;

[0020] Figure 8 for Figure 2 BB sectional view;

[0021] The numbers in the diagram are explained as follows: 1 Upper connector, 2 Guide body sleeve, 3 Guide body, 4 Bolt, 5 Main body, 6 Main body sleeve, 7 Inner connecting sleeve, 8 Upper central tube, 9 Screw, 10 Guide head, 11 Inspection piston, 12 Injection valve, 12-1 Variable diameter, 12-2 Boss, 13 Outer connecting sleeve, 14 Plug, 15 Lower connector, 16 Shear pin, 17 Shear pin sleeve, 18 Lower protective sleeve, 19 Vulcanizing rubber sleeve, 20 Upper protective sleeve, 21 Lower central tube, 22 Valve seat, 23 Valve core spring, 24 Valve core, 25 Sealing cap, 26 Piston, 26-1 Elastic claw, 27 Retaining ring, 28 Injection valve spring, 29 Open snap ring, 30 Injection flow channel, 31 Seal A, 32 Seal B, 33 Contact surface C, 34 Setting seal liquid inlet channel, 35 Inspection seal section, 36 Bridge channel, 37 Hole. Detailed Implementation

[0022] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the following description is provided in conjunction with the appendix. Figures 1-8 The present invention will be further described in detail below with reference to specific embodiments.

[0023] The reusable, integrated water injection tool for sealing large channels in this embodiment has the following specific structure:

[0024] The upper connector 1 is connected and fixed to the guide body sleeve 2 via threads. The main body 5 is connected and fixed to the guide body sleeve 2 via threads; the guide body 3 is fixed to the left end face of the main body 5 via bolts 4; the main body sleeve 6 is connected and fixed to the main body 5 via threads; the inner connecting sleeve 7 is connected and fixed to the main body 5 via threads; the upper central tube 8 is connected and fixed to the inner connecting sleeve 7 via threads; the guide head 10 is inserted into the upper central tube 8 and fixed by screws 9; the retaining spring 27 is installed on the upper central tube 8 via threads; the injection valve and injection valve spring 28 are both sleeved on the outside of the upper central tube 8, and under the action of the injection valve spring 28, the injection valve 12 is in close contact with the main body sleeve 6 to form a seal A31 (see Figure 1 The sealing piston 11 is fitted outside the upper central tube 8 and contacts the inner connecting sleeve 7. The open retaining ring 29 is installed in the groove on the inner connecting sleeve 7 and protrudes from the groove by a certain distance (see...). Figure 4 This allows the sealing piston 11 to move only a certain distance within the range to the left of the opening snap ring 29. After the sealing section 35 is installed, the injection valve 12 can be retracted from its contact with the main body outer sleeve 6, opening the seal A31 and introducing the liquid flow from the sleeve into the sleeve pressure gauge, thus achieving the purpose of verifying whether the packer is sealed. The outer connecting sleeve 13 is connected and fixed to the main body outer sleeve 6 by threads; the piston 26 is sleeved outside the upper middle tube 8 and inserted into the outer connecting sleeve 13, and can move left and right under the action of internal or external pressure. The valve seat 22 is connected and fixed to the outer connecting sleeve 13 by threads. The sealing cap 25 is inserted into the hole on the valve seat 22, the valve core 24 is inserted into the valve seat 22, and the valve core spring 23 is sleeved on the valve core 24 with a certain amount of compression, so that the valve core 24 contacts the sealing cap 25 to form a seal B32 (see Figure 3 The injection valve 12 and piston 26 are connected at contact surface C33. The lower central tube 21 is connected and fixed to the valve seat 22 by threads; the upper protective sleeve 20 is connected and fixed to the valve seat 22 by threads; the vulcanizing rubber sleeve 19 is sleeved outside the lower central tube 21 and connected and fixed to the upper protective sleeve 20 by threads, while a certain gap is left between the inside of the vulcanizing rubber sleeve 19 and the outside of the lower central tube 21 for liquid passage; the lower protective sleeve 18 is connected and fixed to the vulcanizing rubber sleeve 19 by threads; the lower connector 15 is connected and fixed to the lower central tube 21 by threads; the shear pin sleeve 17 is sleeved outside the lower connector 15 and connected to the lower protective sleeve 18 by threads; the shear pin 16 is installed on the shear pin sleeve 17 by threads and inserted into the annular groove of the lower connector 15 and fixed. The plug 14 is inserted into the cross hole on the main body 5, and the plug 14 is fixed in the hole by external plug welding, see reference. Figure 2 .

[0025] The working principle and usage method of this embodiment:

[0026] (a) Tool lowering into the well: Before lowering the tool into the well, place the standard plug (adjustable plug) in the well. Figure 1 The tool is inserted into the center hole 37 and then connected to the appropriate position on the tubing string (multiple stages can be connected in series) and lowered into the well along with the injection tubing string.

[0027] (II) Tool Release: After well completion, open the injection line production valve. Since the pressure from the injection line is much greater than the pressure inside the casing, first push piston 26 to the left to make it tightly contact injection valve 12. Due to the combined pushing action of piston 26 and injection valve spring 28 on injection valve 12, injection valve 12 remains in contact with the main body outer sleeve 6 to form a seal. See... Figure 1 The middle seal A31 closes the injection flow passage 30, while the high-pressure fluid in the oil pipe flows through the setting seal inlet passage 34 (see...). Figure 1 ) Enters the right side of piston 26, and when the pressure exceeds the pressure set by valve core spring 23, it pushes valve core 24 to the right to seal B32 (see Figure 8 The high-pressure fluid continues to enter the gap between the vulcanizing sleeve 19 and the lower central tube 21, causing the vulcanizing sleeve 19 to expand outward. This eventually allows the vulcanizing sleeve 19 to tightly adhere to the casing, forming an effective seal and dividing each stage into independent spaces to prevent layering. When the vulcanizing sleeve forms an effective seal, the pressure inside the oil pipe exceeds the elastic claw 26-1 of the piston 26 (see...). Figure 8 When the pressure that the elastic claw 26-1 can withstand is injected into the boss 12-2 on valve 12 (see...) Figure 6 The piston 26 expands outward and moves to the left under pressure until it contacts and is stopped by the retaining ring 27. When the elastic claw 26-1 of the piston 26 moves to the reducing diameter 12-1 of the injection valve 12 (see... Figure 6 When it springs back to its initial state, the injection valve 12 is subjected to only a small force from the injection valve spring 28, making it easy to push the injection valve 12 to the right and open the seal A31 (see...). Figure 1 The flow channel is formed and enters the bottom layer through the injection channel 30 to complete the injection production.

[0028] After the tool is released, a sealing verification process (to check the sealing performance of the rubber sleeve) is required. This necessitates deploying the sealing section 35 to the tool's response position (see...). Figure 1 After the sealing section is engaged, the pressure in the oil pipe on the left side of the sealing section will be transmitted to the right side of the sealing section through the bridge channel 36, pushing the seal inspection piston 11 to move to the right. Due to the presence of the open snap ring 29, its movement limit is now limited to a certain range to the left of the open snap ring 29, but this distance is sufficient to push the injection valve 12 away from the seal A31 (see...). Figure 1 This allows for internal and external communication, thus achieving the purpose of sealing verification.

[0029] See the direction of flow Figure 8 .

[0030] (III) Well washing and unsealing

[0031] When well washing is required, first close the injection line valve, connect the tubing to the receiving tank, and release the tubing pressure. Then open the casing well washing line valve. At this time, because the pressure inside the casing is greater than the pressure inside the tubing, first push the injection valve 12 to the left and form a seal A again (see...). Figure 1 Simultaneously, it pushes piston 26 to the right, causing the elastic claw to open again through boss 12-2 of injection valve 12 (see...). Figure 6 After the elastic claw 26-1 passes through the boss 12-2, it automatically springs back to its initial state. The piston 26 continues to move to the right, contacting and pushing the valve core 24 to move to the right and opening the seal B32 (see...). Figure 3 The high-pressure fluid inside the vulcanized rubber sleeve 19 is released into the tubing. The vulcanized rubber sleeve 19 retracts and unseals under the action of elasticity. After the sleeve is unsealed, the high-pressure fluid in the casing continues to descend and unseal all the vulcanized rubber sleeves 19 one by one until the last vulcanized rubber sleeve is unsealed. Then the tubing and casing are connected, and the well washing fluid is reverse circulated from the tubing to the wellhead receiving tank, completing the well washing process.

[0032] After well washing is completed, the well washing pipeline valve is closed, and the injection pipeline production valve is opened to restart the tool release process. This setting and unsealing are both automated via the injection pipeline, saving the need for pump pressurization. If tubing string needs to be pulled out, the production valve on the injection pipeline can be opened after well washing, avoiding the major overhaul problems caused by difficulties in unsealing conventional packers and saving operating costs.

[0033] The tool in this embodiment has excellent application prospects due to its technical features such as repeated setting and unsetting; unsetting during well washing and setting during water injection; large and efficient well washing channel; anti-backflow function; and easy unsealing of the packer.

[0034] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. A packer and water injection tool integrated with repeatable setting and large passage, characterized in that, It includes an upper connector, a guide body sleeve screwed to the upper connector, a main body screwed to the guide body sleeve, a guide body fixed on the left end face of the main body, a main body sleeve screwed to the main body, an inner connecting sleeve screwed to the main body, and an upper central tube screwed to the inner connecting sleeve. The guide head is inserted into the upper central tube and fixed. The retaining spring is screwed onto the upper central tube. The injection valve and the injection valve spring are both sleeved on the outside of the upper central tube and, under the action of the injection valve spring, make the injection valve and the main body sleeve tightly contact to form a seal A. The piston sleeve is placed outside the upper central tube and contacts the inner connecting sleeve. The open snap ring is installed in the groove on the inner connecting sleeve and protrudes from the groove by a certain distance. The outer connecting sleeve is screwed to the outer sleeve of the main body. The piston sleeve is placed outside the upper central tube and inserted into the inner connecting sleeve, moving left and right under the action of internal or external pressure. The valve seat is screwed to the outer connecting sleeve. The lower central tube and the upper protective sleeve are screwed to the valve seat respectively. The vulcanized rubber sleeve is placed outside the lower central tube and screwed to the upper protective sleeve. The lower protective sleeve is screwed to the vulcanized rubber sleeve. The lower connector is screwed to the lower protective sleeve. The shear pin sleeve is placed outside the lower connector and screwed to the lower protective sleeve. The shear pin screwed to the shear pin sleeve is inserted into the annular groove of the lower connector and fixed.

2. The repeatable-set, large-duct completion packer and water injection tool integration of claim 1, wherein, The sealing piston is limited to move to its left by an open snap ring.

3. The repeatable-set, large-duct completion packer and water injection tool integration of claim 1, wherein, A gap is left between the inside of the vulcanized rubber cylinder and the outside of the lower middle tube for liquid to pass through.

4. The repeatable-set, large-duct completion packer and water injection tool integration of claim 1, wherein, When the pressure inside the oil pipe exceeds the pressure that the piston's elastic claw can withstand, the elastic claw is pushed outward by the boss on the injection valve and moves under pressure until it contacts the retaining ring and is limited. When the piston's elastic claw moves to the diameter change point of the injection valve, it will spring back to the initial state.

5. The repeatable-set, large-duct completion packer and water injection tool integration of claim 1, wherein, After the piston moves, it contacts the valve core and pushes the valve core to open seal B.

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