Hole temporary plugging soluble injection allocation device, process pipe column and use method

Abstract

The invention discloses a hole temporary plugging soluble injection allocation device, a process pipe column and a using method. The injection allocation device comprises a barrel, and a plurality of sets of injection holes are formed in the barrel; the injection hole comprises a first hole channel and a second hole channel; wherein one end of the first duct is communicated with the end face opening of the cylinder, the other end of the first duct is communicated with the interior of the cylinder, and one end of the second duct is communicated with the first duct; a one-way valve is arranged in the first hole channel, and a soluble blocking core is arranged in the second hole channel. According to the soluble injection allocation device and the oil extraction oil pipe, the soluble blocking core is creatively used, a closed space can be formed within a period of time after the oil extraction oil pipe is put down, a packer can be set through pressing, then the blocking core of the injection allocation device is automatically dissolved in clear water, and the original function of a one-way valve is recovered.

Description

Technical Field

[0001] The present invention belongs to the technical field of oilfield development engineering, and particularly relates to a hole temporarily plugged soluble injection allocator, a process string and a usage method thereof. Background Art

[0002] The bottom end of a traditional process tubing is a differential pressure opened injection allocator, and the water injection or gas injection at the remaining layers all adopt ball dropped opened injection allocators. During the process of stratified water injection or gas injection in a production tubing, after opening the first-stage differential pressure type one-way injection allocator, since a relatively high pressure cannot be formed again inside the tubing, the remaining injection allocators all adopt the ball dropping method to open. Before opening a ball dropped injection allocator, a soluble ball matching the size of the ball seat of the injection allocator needs to be dropped; when the ball reaches the ball seat, a high pressure will be formed inside the tubing; after a differential pressure is formed inside and outside the injection allocator, the shear pin of the inner sleeve of the injection allocator is cut and the sleeve moves to open the water injection or gas injection channel, so as to achieve the purpose of stratified water injection or gas injection. However, the ball seat sizes of the ball dropped opened injection allocators are gradually reduced, so the number of layers and the displacement of water injection or gas injection are limited, and it is difficult to meet the requirements of multi-layer water injection or gas injection.

[0003] The patent application with the publication number of CN112031730A and the name of mechanical horizontal well alternate injection-production technology between fractures for oil production is composed of a wellhead sealing device, an oil production wellhead, a tubing, a conventional sucker rod pump, an anchor releasing device, a safety joint, a packer, a ball dropped one-way injection allocator, a one-way production allocator, a differential pressure type one-way injection allocator and a plug. It solves the problem of effectively exploiting difficult-to-produce reserves in an oilfield, can continue to use the fractures between sections as injection-production channels after the horizontal well is developed by fracturing and depleted, supplement the formation energy and improve the recovery factor. However, this patent application cannot meet the requirements of multi-layer water injection or gas injection. Summary of the Invention

[0004] In order to overcome the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a hole temporarily plugged soluble injection allocator, a process string and a usage method thereof, which dissolve the soluble plugging core of the injection allocator and realize water injection or gas injection into the formation through a one-way valve, so that the number of layers of water injection, gas injection and oil production is not limited by the ball seat and the size of the pressure building ball of the traditional injection allocator, and the requirements of multi-layer water injection or gas injection are realized.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A hole temporarily plugged soluble injection allocator, comprising: an injection allocator, the injection allocator includes a cylinder body, and a plurality of groups of injection holes are opened on the cylinder body; the injection holes include a first hole channel and a second hole channel; wherein, one end of the first hole channel is communicated with the end face opening of the cylinder body, and the other end is communicated with the inside of the cylinder body, one end of the second hole channel is communicated with the first hole channel, and the other end is communicated with the outside of the cylinder body; a one-way valve is arranged in the first hole channel, and a soluble plugging core is arranged in the second hole channel.

[0007] Optionally, the included angle between the first channel and the axis of the cylinder body is 20° to 40°.

[0008] Optionally, the first channel is perpendicular to the second channel.

[0009] Optionally, the soluble plugging core includes a soluble matrix, and a protective layer is arranged outside the soluble matrix. The protective layer includes end protective layers arranged at both ends of the soluble matrix and a side protective layer arranged on the side of the soluble matrix.

[0010] Optionally, the material of the side protective layer is ceramic, and the material of the end protective layer is a soluble polymer material or a grease with high viscosity.

[0011] Grooves are provided on the side of the soluble matrix and on the outer side of the side protective layer, and sealing rings are arranged in the grooves of the soluble matrix and the grooves of the side protective layer.

[0012] Optionally, the check valve includes a valve element. One end of the valve element is connected to a valve seat, and the other end is connected to a spring seat. A spring is sleeved outside the valve element.

[0013] A process string includes an oil pipe. The oil pipe includes a vertical section and a horizontal section. A sucker rod pump and a hanger are arranged in the vertical section, and a plurality of flow regulators and injection regulators are arranged in the horizontal section. A packer is arranged between the flow regulator and the injection regulator.

[0014] Optionally, the flow regulators and the injection regulators are arranged at intervals.

[0015] The usage method of the described process string includes the following steps:

[0016] Pump clear water into the oil pipe. After the pipe is filled with water, the shear pin of the packer sliding sleeve is cut short and the rubber cylinder expands to complete setting;

[0017] The soluble plugging core moves axially, the end protective layer loses its protection effect, and the soluble matrix starts to dissolve after contacting the clear water;

[0018] After the soluble plugging core dissolves, the clear water or gas in the oil pipe flows through the check valve to the annulus area outside the oil pipe, realizing the water injection or gas injection construction of the formation.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The soluble injection regulator and the oil production pipe of the present invention creatively use a soluble plugging core, which can form a closed space in the oil production pipe for a period of time after it is lowered. By applying pressure, the packer can be set, and then the plugging core of the injection regulator automatically dissolves in the clear water, restoring the original function of the check valve.

[0021] Furthermore, the soluble injector and all injectors have a unified inner diameter, and the number of layers for water injection or gas injection and oil production is no longer restricted by the sizes of the ball seats and pressure-holding balls of traditional injectors.

[0022] Furthermore, the injector of the present invention has a simple structure. The cylinder body is an integral part, and its load-bearing capacity is much higher than that of traditional injectors with a multi-layer structure.

[0023] Furthermore, the field construction process of the injector of the present invention is less. It does not require the assistance of other equipment, which is convenient for workers to operate, avoids misoperation accidents such as incorrect ball-throwing sequences, improves production efficiency, and has great engineering practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The drawings described herein are for illustrative purposes only and are not intended to limit the scope of the disclosure of the present invention in any way. Additionally, the shapes and proportional dimensions of the components in the drawings are only schematic and are used to assist in understanding the present invention, rather than specifically defining the shapes and proportional dimensions of the components of the present invention. In the drawings:

[0025] Figure 1 is a schematic structural diagram of a soluble water injector process tubing of the present invention;

[0026] Figure 2 is a schematic cross-sectional structural diagram of a perforation temporary plugging soluble injector of the present invention;

[0027] Figure 3 is a schematic internal structural diagram of a perforation temporary plugging soluble injector of the present invention;

[0028] Figure 4 is a schematic structural diagram of a soluble plugging core of the present invention;

[0029] Figure 5 is a schematic structural diagram of a check valve of the present invention.

[0030] Wherein, 1, tubing; 2, sucker rod pump; 3, hanger; 4, packer; 5, flow controller; 6, injector; 7, guide head; 8, cylinder body; 9, check valve; 10, soluble plugging core; 11, first end protective layer; 12, soluble matrix; 13, sealing ring; 14, side protective layer; 15, second end protective layer; 16, valve seat; 17, valve; 18, spring; 19, sealing ring; 20, spring seat. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] To enable those skilled in the art to better understand the technical solutions in the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0032] It should be noted that when an element is referred to as being "disposed on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0034] The following will describe the present invention in detail in conjunction with the accompanying drawings.

[0035] As Figure 1 shown, a production string 1 with a soluble injector includes a tubing 1. The tubing 1 includes a vertical section and a horizontal section. A sucker rod pump 2 and a hanger 3 are disposed in the vertical section, and a plurality of flow controllers 5 and injectors 6 are disposed in the horizontal section. The flow controllers 5 and the injectors 6 are arranged at intervals, and packers 4 are disposed between the flow controllers 5 and the injectors 6. A guide head 7 is disposed at the end of the horizontal section.

[0036] As Figure 2 and Figure 3 shown, the perforation temporary plugging soluble injector 6 includes: a cylinder body 8, a check valve 9 and a soluble plugging core 10.

[0037] The cylinder body 8 is in the shape of a hollow stepped shaft. A plurality of groups of injection holes are provided on the side surface of the cylinder body 8 for water injection or gas injection. Each group of injection holes has a first hole and a second hole. The angle between the first hole and the axis of the cylinder body 8 is 20° to 40°, and they intersect at a point on the axis of the cylinder body 8. One end of the first hole is communicated with the end face opening of the cylinder body 8, and the other end is communicated with the inner wall of the cylinder body 8.

[0038] The second channel is perpendicular to the axis of the first channel. One end of the second channel communicates with the first channel, and the other end communicates with the outer side of the cylinder body 8. A check valve 9 is arranged in the first channel and covers the holes at the end face opening of the cylinder body 8; a soluble plugging core 10 is arranged on the second channel.

[0039] The soluble plugging core 10 is installed inside the second channel and covers the injection hole of the cylinder body 8. The soluble plugging core 10 is connected to the cylinder body 8 by threads, and the injection hole can limit and fix the soluble plugging core 10. Specifically, the diameter of one end of the soluble plugging core 10 is larger than the diameter of the injection hole.

[0040] As Figure 4 shown, the soluble plugging core 10 includes a soluble matrix 12. A protective layer is arranged outside the soluble matrix 12. The protective layer includes an end protective layer and a side protective layer 14. The end protective layer includes a first end protective layer 11 and a second end protective layer 15. The protective layer can ensure that the soluble plugging core 10 does not corrode before entering the well. The first end protective layer 11 and the second end protective layer 15 are respectively arranged at both ends of the soluble matrix 12, and the side protective layer 14 is arranged on the side of the soluble matrix 12.

[0041] Optionally, the soluble plugging core 10 is cylindrical or stepped cylindrical.

[0042] Grooves are provided on the side of the soluble matrix 12 and on the outer side of the side protective layer 14. Sealing rings 13 are arranged in the grooves of the soluble matrix 12 and the side protective layer 14.

[0043] Optionally, the protective layer is made of an insulating material. Specifically, the material of the side protective layer 14 is ceramic. Optionally, the material of the end protective layer is a soluble polymer material or a grease with high viscosity.

[0044] Before setting the packer 4, the side protective layer 14 can prevent the soluble matrix 12 from corroding; when setting the packer 4, the soluble plugging core 10 will have a certain axial displacement, and the end protective layer can be detached and dissolved or diluted to ensure that the soluble matrix 12 starts to dissolve when contacting with the liquid. After dissolution, the injector 6 resumes the function of one-way liquid flow.

[0045] As Figure 5 shown, the check valve 9 includes a valve seat 16, a valve 17, a spring 18, a spring seat 20 and a sealing ring 19.

[0046] One end of the valve 17 is connected to the valve seat 16, and the other end is connected to the spring seat 20. A spring 18 is sleeved outside the valve 17. Grooves are provided on the outer sides of both the valve seat 16 and the spring seat 20, and sealing rings 19 are arranged in the grooves. The check valve 9 allows liquid to flow from the inside of the tubing 1 to the annulus area outside the tubing 1.

[0047] Embodiment:

[0048] When a process tubing string of the present invention is in use, it includes the following steps:

[0049] Step 1: After the tubing 1 is lowered into the well, first perform the operation of setting the packer 4: Pump clear water into the tubing 1. The inside of the tubing 1 is in a closed state. After the tubing 1 is filled with water, pressurize it to a certain pressure. The sliding sleeve shear pin of the packer 4 is cut off and the rubber cylinder expands to complete the setting, thereby realizing the layered isolation of the annulus area of the production tubing 1.

[0050] Step 2: The soluble plug core 10 moves axially, and the end protective layer loses its protective effect. After the soluble matrix 12 comes into contact with clear water, it begins to dissolve.

[0051] Step 3: Perform the operation of water injection or gas injection. After the soluble plug core 10 dissolves, the clear water or gas inside the tubing 1 can flow through the check valve 9 to the annulus area outside the tubing 1, realizing the water injection or gas injection operation on the formation.

[0052] In the above embodiments, the equipment components involved are all conventional equipment components without special instructions. The structural setting methods, working methods, or control methods involved are all conventional setting methods, working methods, or control methods in the art without special instructions.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not restrictive. Other modifications or equivalent replacements made by those of ordinary skill in the art to the technical solutions of the present invention should be covered within the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solutions of the present invention.

Claims

1. A hole temporarily pluggable and soluble injection device, Characterized in that, Comprising: An injection device (6), the injection device (6) includes a cylinder body (8), and a plurality of groups of injection holes are opened on the cylinder body (8); the injection holes include a first hole and a second hole; wherein, one end of the first hole is communicated with the end face opening of the cylinder body (8), and the other end is communicated with the inside of the cylinder body (8), one end of the second hole is communicated with the first hole, and the other end is communicated with the outside of the cylinder body (8); a check valve (9) is arranged in the first hole, and a soluble plug core (10) is arranged in the second hole.

2. A hole temporarily pluggable and soluble injection device according to claim 1, Characterized in that, The included angle between the first hole and the axis of the cylinder body (8) is 20° to 40°.

3. A hole temporarily pluggable and soluble injection device according to claim 1, Characterized in that, The first hole is perpendicular to the second hole.

4. A hole temporarily pluggable and soluble injection device according to claim 1, Characterized in that, The soluble plug core (10) includes a soluble matrix (12), a protective layer is arranged outside the soluble matrix (12), and the protective layer includes an end protective layer arranged at both ends of the soluble matrix (12) and a side protective layer (14) arranged on the side of the soluble matrix (12).

5. A hole temporarily pluggable and soluble injection device according to claim 4, Characterized in that, The material of the side protective layer (14) is ceramic, and the material of the end protective layer is a soluble polymer material or a grease with high viscosity.

6. A hole temporarily pluggable and soluble injection device according to claim 4, Characterized in that, Both the side of the soluble matrix (12) and the outside of the side protective layer (14) have grooves, and sealing rings (13) are arranged in the grooves of the soluble matrix (12) and the side protective layer (14).

7. A hole temporarily pluggable and soluble injection device according to claim 1, Characterized in that, The check valve (9) includes a valve element (17), one end of the valve element (17) is connected with a valve seat (16), the other end is connected with a spring seat (20), and a spring (18) is sleeved outside the valve element (17).

8. A process string, Characterized in that, Comprising an oil pipe (1), the oil pipe (1) includes a vertical section and a horizontal section, a sucker rod pump (2) and a hanger (3) are arranged in the vertical section, a plurality of production distributors (5) and injection devices (6) are arranged in the horizontal section, the production distributors (5) and the injection devices (6) are arranged at intervals, and a packer (4) is arranged between the production distributors (5) and the injection devices (6).

9. A process string according to claim 8, Characterized in that, The diameters of a plurality of the injection devices (6) are the same.

10. A method for using a process string according to any one of claims 8 to 9, Characterized in that, Comprising the following steps: Pump clear water into the oil pipe (1), after filling with water, the slip shear pin of the packer (4) is cut short and the rubber cylinder expands to complete setting; The soluble plugging core (10) moves axially, the end protective layer loses its protective effect, and the soluble matrix (12) starts to dissolve after contacting clean water; After the soluble plugging core (10) dissolves, the clean water or gas in the tubing (1) flows through the check valve (9) to the annulus area outside the tubing (1), realizing the water injection or gas injection construction for the formation.

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