Current-limiting screen pipe well completion tool for water injection well and use method of current-limiting screen pipe well completion tool

Abstract

The invention relates to a flow-limiting screen pipe completion tool for a water injection well and a using method. The flow-limiting screen pipe completion tool for the water injection well comprises a flow-limiting screen pipe body, and a packer is arranged on the side wall of the flow-limiting screen pipe body; a plurality of first hole structures for uniformly distributing acid and uniformly injecting water are arranged on the side wall of the flow-limiting screen pipe body, and the first hole structures are arranged in a through and open manner; a plurality of second hole structures used for balanced water injection are further arranged on the side wall of the flow limiting screen pipe body, the second hole structures are controllably opened, the second hole structures are closed during acid distribution, and the second hole structures are opened during water injection. Uniform acid distribution of the long horizontal well in the acidification stage and balanced water injection in the water injection stage are achieved at the same time, the problem that injection water rushes along a high-permeability channel to cause low sweep efficiency is solved to the maximum extent, and therefore the water injection effect of the long horizontal well section is improved, and efficient water injection development of an oil field is supported.

Description

Technical Field

[0001] The present invention relates to the field of oil and gas, and in particular to a limited-entry screen completion tool for injection wells and a usage method thereof. Background Art

[0002] Before an oil and gas well is put into production, an acidizing operation is generally carried out to remove the reservoir pollution caused during the drilling and completion processes. However, for a long horizontal well section (generally considered that the horizontal section length is greater than 1000 meters), due to the certain frictional resistance of the acid fluid flowing in the horizontal section, there will be a difference in the injection pressure difference between the heel and the toe of the horizontal section, which will further lead to uneven acid injection amounts in each section and fail to achieve the expected acidizing effect. Using a limited-entry liner (LEL) is one of the means to solve the problem of uneven acid injection in a long horizontal well section. It was first proposed by Shell in the 1960s and has been widely used in regions such as the North Sea and the Middle East. Currently, the industry has formed a design method for limited-entry liner completion and acidizing, mainly by pre-designing the number of screen holes in each section before the limited-entry liner is lowered into the well to achieve the purpose of uniform acid injection in each section during the acidizing process.

[0003] Currently, the limited-entry liners in the industry are mainly used to solve the problem of uneven acid injection profile during the acidizing process of a long horizontal well section. However, with the increasing number of long horizontal well sections and even MRC wells, another practical problem has emerged: for a horizontal injection well with a limited-entry liner, if a uniform acid distribution is achieved through the design of the hole number distribution, it is impossible to achieve a uniform injection profile during the water injection stage (because the water injection flow rate is generally lower than the acidizing displacement, and a weaker limited-entry effect is required); if a uniform water injection is achieved by adjusting the hole number distribution, then uniform acid injection cannot be achieved during the acidizing stage. Because when a limited-entry liner is installed, it is generally used in conjunction with a permanent packer and cannot be removed once it is lowered into the well, and it is impossible to adjust the hole distribution of the limited-entry liner on the ground.

[0004] Therefore, based on the experience and practice of being engaged in the relevant industry for many years, the inventor of the present invention proposes a limited-entry screen completion tool for injection wells and a usage method thereof to overcome the defects of the prior art. Summary of the Invention

[0005] The purpose of the present invention is to provide a limited-entry screen completion tool for injection wells and a usage method thereof, which can simultaneously achieve uniform acid distribution in the acidizing stage and uniform water injection in the water injection stage of a long horizontal wellbore, and maximize the avoidance of the problem of low sweep efficiency caused by the breakthrough of injected water along high-permeability channels, thereby improving the water injection effect of the long horizontal well section and supporting the efficient water injection development of the oilfield.

[0006] The object of the present invention is achieved as follows. A limited-flow screen completion tool for injection wells includes a limited-flow screen pipe body, and a packer is arranged on the side wall of the limited-flow screen pipe body; a plurality of first hole structures for uniformly distributing acid and balancing water injection are arranged on the side wall of the limited-flow screen pipe body, and the first hole structures are arranged in a through-open manner; a plurality of second hole structures for balancing water injection are also arranged on the side wall of the limited-flow screen pipe body, and the second hole structures are arranged to be controllably opened. The second hole structures are closed during acid distribution, and the second hole structures are opened during water injection.

[0007] In a preferred embodiment of the present invention, each of the second hole structures includes a second hole body penetrating through the side wall of the limited-flow screen pipe body, and a soluble plug is arranged in the second hole body. The soluble plug can block the second hole body or dissolve to open the second hole body.

[0008] In a preferred embodiment of the present invention, the soluble plug is made of a high-strength solid material that is insoluble in acid, insoluble in water, has a temperature resistance of ≥80 °C and a pressure resistance of ≥10 MPa, and the high-strength solid material can be dissolved by soaking in a special solvent.

[0009] In a preferred embodiment of the present invention, the soluble plug is made of ABS resin.

[0010] In a preferred embodiment of the present invention, the special solvent is dichloromethane.

[0011] In a preferred embodiment of the present invention, the special solvent is dimethylformamide.

[0012] The object of the present invention can also be achieved as follows. A method for using the above-mentioned limited-flow screen completion tool for injection wells includes arranging the first hole structures on the limited-flow screen pipe body of the limited-flow screen completion tool for injection wells according to the acid injection displacement, and arranging the second hole structures on the limited-flow screen pipe body according to the water injection displacement. Before entering the well, the first hole structures are through-opened and the second hole structures are closed; the limited-flow screen completion tool for injection wells is lowered into the well for general acidification operation, and the acid liquid enters the wellbore through the first hole structures; after the acidification operation is completed, coiled tubing is lowered to displace the special solvent until the horizontal section of the wellbore is filled, and soaked for a set time to completely dissolve the soluble plug and open the second hole structures by dredging; the special solvent is displaced, and water injection operation is carried out according to the set water injection flow rate.

[0013] In a preferred embodiment of the present invention, acid is injected from the wellhead at a displacement of 20 barrels / min for general acidification operation, and the displacement remains constant during the injection process.

[0014] In a preferred embodiment of the present invention, after the acidification operation is completed, coiled tubing is run in to displace with methylene chloride that fills the horizontal section of the wellbore, and soaked for 24 hours. The soluble blockages are completely dissolved, and the second hole structure is unclogged and opened.

[0015] In a preferred embodiment of the present invention, after the special solvent is displaced, water injection operation is carried out at a displacement rate of 7.0 barrels / min.

[0016] As described above, the limited-entry screen completion tool for injection wells and its usage method of the present invention have the following beneficial effects:

[0017] In the present invention, two types of hole patterns are set. The first hole structure is a permanently open hole, and the second hole structure is a preset controllable open hole. During the acid injection stage, only the first hole structure functions to achieve uniform acid distribution in each section of the horizontal well. After acidification is completed, the second hole structure is controlled to open, and both the first hole structure and the second hole structure are opened and function together to jointly form the water injection holes, realizing the rearrangement of the number of holes in the limited-entry screen in the horizontal well section and meeting the requirements of balanced water injection.

[0018] The present invention realizes uniform acid distribution in the acidification stage and balanced water injection in the water injection stage of the long horizontal wellbore, maximally avoiding the problem of low sweep efficiency caused by the breakthrough of the injected water along the high-permeability channel, thereby improving the water injection effect in the long horizontal well section and supporting the efficient water injection development of the oilfield. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The following drawings are only intended to illustrate and explain the present invention schematically and do not limit the scope of the present invention.

[0020] Wherein:

[0021] Figure 1 : is a schematic diagram of the limited-entry screen completion tool for injection wells of the present invention.

[0022] Figure 2 : is a schematic diagram of the limited-entry screen completion tool for injection wells of the present invention during the water injection process.

[0023] Figure 3 : is a schematic diagram of the downhole operation state of the limited-entry screen completion tool for injection wells of the present invention.

[0024] Figure 4 : is the hole pattern during the acidification operation of the embodiment of the present invention.

[0025] Figure 5 : is the hole pattern of the limited-entry screen during the water injection of the embodiment of the present invention.

[0026] Figure 6 : is the calculation result of the number of the second hole structures, the number of the first hole structures and the total number of holes in the embodiment of the present invention.

[0027] In the figure:

[0028] 1. Flow-limiting screen pipe body; 11. First hole structure; 12. Second hole structure; 121. Second hole body; 122. Soluble plug

[0029] 2. Packer

[0030] 3. Horizontal section wellbore Detailed implementation manners

[0031] For a clearer understanding of the technical features, objectives, and effects of the present invention, the detailed implementation manners of the present invention will now be described with reference to the accompanying drawings.

[0032] The detailed implementation manners of the present invention described herein are only for the purpose of explaining the present invention and should not be construed in any way as a limitation of the present invention. Under the teaching of the present invention, those skilled in the art can conceive of any possible variations based on the present invention, and these should all be regarded as belonging to the scope of the present invention. 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 can 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 "mounted", "connected", and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the communication inside two elements. It can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances. The terms "vertical", "horizontal", "upper", "lower", "left", "right", and similar expressions used herein are only for the purpose of illustration and do not represent the only implementation manner.

[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 this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific implementation manners and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0034] As Figures 1 to 3As shown in the figure, the present invention provides a limited-flow screen completion tool for injection wells, which includes a limited-flow screen pipe body 1. A packer 2 is arranged on the side wall of the limited-flow screen pipe body 1, and the packer 2 divides the horizontal section wellbore 3 into multiple sections; a plurality of first hole structures 11 for uniformly distributing acid and balancing water injection are arranged on the side wall of the limited-flow screen pipe body 1, and the first hole structures 11 are arranged in a through and open manner; a plurality of second hole structures 12 for balancing water injection are also arranged on the side wall of the limited-flow screen pipe body 1, and the second hole structures 12 are arranged to be controllably opened. When distributing acid, the second hole structures 12 are closed, and when injecting water, the second hole structures 12 are opened.

[0035] Two types of hole structures are arranged on the limited-flow screen pipe body 1: the first hole structure 11 is a permanently open hole, and the second hole structure 12 is a controllably open hole. The quantity and distribution of these two types of holes can be pre-designed through special software.

[0036] Before the limited-flow screen pipe body 1 is lowered into the well, the second hole structures 12 are blocked and closed; during the acid injection stage, only the first hole structures 11 function, forming acid injection holes, which play a role in restricting the flow of acid liquid and realizing uniform acid distribution in each section of the horizontal well.

[0037] After the acidification operation is completed and before water injection, control the second hole structures 12 to open. Both the first hole structures 11 and the second hole structures 12 are opened and function together, jointly forming water injection holes, realizing the rearrangement of the number of holes in the limited-flow screen of the horizontal well section, and meeting the requirements of balanced water injection.

[0038] In the present invention, two types of hole structures are set. The first hole structure 11 is a permanently open hole, and the second hole structure 12 is a preset controllably open hole. During the acid injection stage, only the first hole structures 11 function to realize uniform acid distribution in each section of the horizontal well. After acidification is completed, control the second hole structures 12 to open. Both the first hole structures 11 and the second hole structures 12 are opened and function together, jointly forming water injection holes, realizing the rearrangement of the number of holes in the limited-flow screen of the horizontal well section, and meeting the requirements of balanced water injection;

[0039] The present invention realizes uniform acid distribution in the acidification stage and balanced water injection in the water injection stage of the long horizontal wellbore, maximally avoiding the problem of low sweep efficiency caused by the breakthrough of injected water along the high-permeability channel, thereby improving the water injection effect of the long horizontal well section and supporting the efficient water injection development of the oilfield.

[0040] Further, as Figure 1 shown, each second hole structure 12 includes a second hole body 121 penetrating through the side wall of the limited-flow screen pipe body 1. A soluble plug 122 is arranged in the second hole body 121, and the soluble plug 122 can block the second hole body 121 or dissolve to open the second hole body 121.

[0041] Further, the soluble plug 122 is made of a high-strength solid material that is insoluble in acid, insoluble in water, resistant to temperatures ≥80°C, and pressure ≥10 MPa, and the high-strength solid material can be dissolved by soaking in a special solvent.

[0042] In a specific embodiment of the present invention, the soluble plug 122 can be made of ABS (i.e., Acrylonitrile Butadiene Styrene) resin, or other chemical materials that meet the above conditions.

[0043] Further, the special solvent should be a chemical agent that can quickly dissolve the "special material" (generally considered to be completely dissolved within 24 hours under wellbore conditions), and the special solvent should not corrode the oil casing or damage the reservoir. When the soluble plug 122 is made of ABS resin, the special solvent is dichloromethane or dimethylformamide, or other chemical agents that meet the above conditions.

[0044] The present invention also provides a method for using a limited-entry screen completion tool for injection wells. When using the above tool, the design and operation procedures of limited-entry screen completion and acidification also need to be adjusted accordingly. After the conventional limited-entry screen is installed, acidification and subsequent other operations can be carried out; when using the limited-entry screen completion tool for injection wells of the present invention, the following procedures need to be operated to achieve its dual functions:

[0045] Step a: On the limited-entry screen pipe body 1 of the limited-entry screen completion tool for injection wells, the first hole structure 11 is arranged according to the acid injection rate, and the second hole structure 12 is arranged according to the water injection rate. Before entering the well, the first hole structure 11 is opened through and the second hole structure 12 is closed.

[0046] Before entering the well, two sets of hole distributions are designed according to the acid injection rate and the water injection rate respectively; the first hole structure 11 designed according to the acid injection rate is the "permanently opened hole"; the number of holes designed according to the water injection rate is generally more than the first hole structure 11 designed according to the acid injection rate, and the difference between the two is the second hole structure 12 (controllable opening hole); before the limited-entry screen completion tool enters the well, the screen pipe is selected on the ground according to the number of holes designed according to the water injection rate, and then the second hole structure 12 is blocked and sealed with the soluble plug 122.

[0047] Step b: As Figure 3 shown, the limited-entry screen completion tool for injection wells is lowered into the well for general acidification operation, and the acid fluid enters the wellbore through the first hole structure 11.

[0048] Specifically, acid is injected from the wellhead at a rate of 20 barrels / min for general acidification operation, and the rate is kept constant during the injection process.

[0049] Step c: After the acidification operation is completed, run a coiled tubing to displace a special solvent into the horizontal section wellbore 3 until it is full, soak for a set time to completely dissolve the soluble blockage, and unclog and open the second perforation structure.

[0050] Specifically, after the acidification operation is completed, run a coiled tubing to displace methylene chloride for one wellbore, ensuring that at least the horizontal section wellbore is filled with methylene chloride, soak for 24 hours, and the soluble blockage is completely dissolved to unclog and open the second perforation structure.

[0051] Step d: Displace the special solvent and perform a water injection operation at a set water injection flow rate.

[0052] Specifically, remove the coiled tubing equipment, and then start the normal water injection operation at a displacement of 7.0 barrels / min. Try to keep the daily water injection volume stable during the water injection process.

[0053] Example:

[0054] A horizontal water injection well with a horizontal section length of 10,000 feet, equipped with a restricted flow screen for completion and acidification. The wellbore size is 6", and it is prepared to run a 4-1 / 2" restricted flow screen (outer diameter 114.3 mm, inner diameter 100.5 mm). The horizontal section is divided into 10 segments by packers, and acidification is carried out by general injection at the wellhead. After the acidification operation, water injection is performed.

[0055] Acidification displacement: 20 barrels / min; acid density 1.14 g / cm3; acid viscosity 0.65 mPa.s.

[0056] Daily water injection volume: 10,000 barrels / day, converted to an injection displacement of approximately 7.0 barrels / min; injection water density 1.00 g / cm 3 ; injection viscosity 1.35 mPa.s.

[0057] The calculation method for perforation distribution is as follows:

[0058] 1. Determine the expected total production and bottom hole flowing pressure (i.e., the pressure at the toe end of the horizontal section) of the oil well after acidification according to the development production allocation requirements or the oil well production capacity.

[0059] 2. Segment the horizontal section, evenly distribute the expected total production of the oil well to each segment to obtain the expected oil production of each segment.

[0060] 3. Calculate the flow friction of each segment using the pipe flow friction formula, and then calculate the bottom hole flowing pressure of each segment; the pipe flow friction formula can be the following formula: the friction calculation formula for turbulent flow conditions (this invention is applicable to high-production oil wells with turbulent flow regime in the wellbore):

[0061]

[0062] In the formula, △P wfpis the wellbore flow friction during crude oil production, psia; q is the flow rate in the wellbore, STB / d. When calculating in segments, the flow rate in a certain wellbore segment is equal to the total production of all previous segments plus half of the production in this segment, that is, the flow rate in the i-th wellbore segment is: q(i) = q(i - 1) + q in (i) / 2 (q in is the production in the inflow section); l is the length of the flow section, ft; f is the friction coefficient, dimensionless; ρ o is the crude oil density, lbm / ft 3 ; D is the inner diameter of the wellbore, inch.

[0063] The friction coefficient f in the formula is calculated by the following formula:

[0064]

[0065] In the formula, ε is the relative roughness of the pipe wall, dimensionless;

[0066] Re is the Reynolds number of pipe flow, dimensionless, and the calculation formula is:

[0067]

[0068] In the formula, μo is the viscosity of crude oil, cp.

[0069] 4. According to the production of each segment and the bottom-hole flowing pressure, use the horizontal well productivity formula to calculate the expected skin factor (hereinafter referred to as "expected skin factor") after acidification of each segment; the horizontal well productivity formula can adopt Furui's steady-state flow model, that is:

[0070]

[0071] In the formula, q in is the production in the inflow well section, STB / d; k is the average permeability of the reservoir, mD; L is the length of the horizontal section, ft; P e is the reservoir pressure, psia; P wfp is the bottom-hole flowing pressure during production, psia; μ o is the viscosity of crude oil, cp; B 0 is the crude oil system coefficient, dimensionless; h is the reservoir thickness, ft; I ani is the reservoir anisotropy coefficient, dimensionless; y b is half of the reservoir width (the width direction is perpendicular to the horizontal section), ft; s is the skin factor, dimensionless.

[0072] Formula (4) can be transformed into an expression of the skin factor for each segment:

[0073]

[0074] The subscript i represents the parameters of the i-th section. If the calculated "expected skin factor" of a certain section is greater than 0, it is set to 0.

[0075] 5. Calculate the expected acid-etched wormhole length (hereinafter referred to as "expected wormhole length") for each section based on the expected skin factor of each section; the relationship between the skin factor and the acid-etched wormhole length can be expressed by the classic formula of Hawkins et al.:

[0076]

[0077] In the formula, r w is the wellbore diameter, ft; r wh is the acid-etched wormhole length, ft.

[0078] Express the acid-etched wormhole length of each section in Equation (6) as:

[0079]

[0080] The subscript i represents the parameters of the i-th section.

[0081] 6. Calculate the expected acid injection volume (hereinafter referred to as "expected acid injection volume") for each section based on the expected wormhole length of each section; the relationship between the acid-etched wormhole length and the acid injection volume can be expressed by the formula of Economides:

[0082]

[0083] In the formula, COV is the acid usage intensity, bbl / ft; φ is the porosity, dimensionless; PV bt is the PV number of acid penetration through the core, obtained through experiments, dimensionless.

[0084] Similarly, the acid usage intensity of each section can be expressed in Equation (8):

[0085]

[0086] The subscript i represents the parameters of the i-th section.

[0087] 7. Design the number of perforations of the screen pipe for each section based on the expected acid injection volume of each section and in combination with the designed acidizing pumping program.

[0088]

[0089] In the formula, COV is the acid usage intensity, bbl / ft; l is the length of the restricted flow screen pipe section, ft; PV bt is the PV number of acid penetration through the core, obtained through experiments, dimensionless; C D is the perforation flow coefficient, dimensionless; D hole is the inner diameter of the perforation, inch; P wfaiis the bottom hole pressure at the i-th stage during acidification (also calculated according to the wellbore flow friction formula), psia; ρ a is the density of the acid solution, lbm / ft 3 .

[0090] t inj is the acidification construction time, min, which is calculated according to the following formula:

[0091]

[0092] In the formula, Q a is the injection displacement of the acid solution at the wellhead, bbl / min.

[0093] Design according to the above basic parameters, and the obtained hole distribution during acidification (as Figure 4 shown), the hole distribution during water injection (as Figure 5 shown), and the calculated second hole structure 12 (the number of controllable open holes, as Figure 6 shown).

[0094] The on-site operation steps are as follows:

[0095] (1) Before entering the well, select and match the limited flow screen pipe body 1 according to the hole distribution shown Figure 5 . The hole numbers distribution of each section (from the heel end to the toe end) is: 7, 8, 9, 10, 11, 12, 13, 14, 15, 15;

[0096] (2) According to the number of the second hole structure 12 (controllable open holes) in Figure 6 , use ABS resin material (soluble plug) to block the controllable open holes section by section. The number of blocked holes (from the heel end to the toe end) is: 0, 0, 0, 0, 1, 2, 3, 4, 5, 6;

[0097] (3) Lower the limited flow screen pipe completion tool into the well, inject acid from the wellhead at a displacement of 20 bbl / min, and carry out general acidification operation. Keep the displacement constant during the injection process;

[0098] (4) After the acidification operation is completed, lower the coiled tubing to displace dichloromethane into 1 wellbore, soak for 24 hours, and then displace the liquid in the wellbore;

[0099] (5) Remove the coiled tubing equipment, and then start the normal water injection operation at a displacement of 7.0 bbl / min. Try to keep the daily water injection volume stable during the water injection process.

[0100] As described above, the limited flow screen pipe completion tool and its usage method for water injection wells of the present invention have the following beneficial effects:

[0101] In the present invention, two types of holes are provided. The first hole structure is a permanently open hole, and the second hole structure is a preset controllable open hole. During the acid injection stage, only the first hole structure functions to achieve uniform acid distribution in each section of the horizontal well. After acidification is completed, the second hole structure is controlled to open, and both the first hole structure and the second hole structure open and function together to form the water injection holes, realizing the rearrangement of the number of holes in the limited flow screen pipe of the horizontal well section and meeting the requirements of balanced water injection.

[0102] The present invention realizes uniform acid distribution in the acidification stage and balanced water injection in the water injection stage of the long horizontal wellbore, maximally avoiding the problem of low sweep efficiency caused by the breakthrough of injected water along the high-permeability channel, thereby improving the water injection effect of the long horizontal well section and supporting the efficient water injection development of the oilfield.

[0103] The above are only illustrative specific embodiments of the present invention and are not intended to limit the scope of the present invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A limited flow screen completion tool for injection wells, characterized in that, it includes a limited flow screen pipe body, and a packer is arranged on the side wall of the limited flow screen pipe body; a plurality of first hole structures for uniformly distributing acid and balancing water injection are arranged on the side wall of the limited flow screen pipe body, and the first hole structures are arranged in a through and open manner; a plurality of second hole structures for balancing water injection are also arranged on the side wall of the limited flow screen pipe body, and the second hole structures are arranged to be controllably opened. When distributing acid, the second hole structures are closed, and when injecting water, the second hole structures are opened.

2. The limited flow screen completion tool for injection wells according to claim 1, characterized in that, each of the second hole structures includes a second hole body penetrating through the side wall of the limited flow screen pipe body, and a soluble plug is arranged in the second hole body, and the soluble plug can block the second hole body or dissolve and open the second hole body.

3. The limited flow screen completion tool for injection wells according to claim 2, characterized in that, the soluble plug is made of a high-strength solid material that is insoluble in acid, insoluble in water, has a temperature resistance of ≥80 °C and a pressure resistance of ≥10 MPa, and the high-strength solid material can be dissolved by soaking in a special solvent.

4. The limited flow screen completion tool for injection wells according to claim 3, characterized in that, the soluble plug is made of ABS resin.

5. The limited flow screen completion tool for injection wells according to claim 4, characterized in that, the special solvent is dichloromethane.

6. The limited flow screen completion tool for injection wells according to claim 4, characterized in that, the special solvent is dimethylformamide.

7. A method for using the limited flow screen completion tool for injection wells according to any one of claims 1-6, characterized in that, it includes arranging the first hole structures on the limited flow screen pipe body of the limited flow screen completion tool for injection wells according to the acid injection displacement, and arranging the second hole structures on the limited flow screen pipe body according to the water injection displacement. Before entering the well, the first hole structures are through and open and the second hole structures are closed; the limited flow screen completion tool for injection wells is lowered into the well for general acidification operation, and the acid liquid enters the wellbore through the first hole structures; after the acidification operation is completed, coiled tubing is lowered to displace the special solvent until the horizontal section of the wellbore is filled, soaked for a set time to completely dissolve the soluble plug and dredge and open the second hole structures; the special solvent is displaced, and water injection operation is carried out according to the set water injection flow rate.

8. The method for using the limited flow screen completion tool for injection wells according to claim 7, characterized in that, inject acid from the wellhead at a displacement of 20 barrels / min for general acidification operation, and keep the displacement constant during the injection process.

9. The method for using the limited flow screen completion tool for injection wells according to claim 7, characterized in that, after the acidification operation is completed, coiled tubing is lowered to displace dichloromethane to fill the horizontal section of the wellbore, soak for 24 hours, and the soluble plug is completely dissolved to dredge and open the second hole structures.

10. The method for using the limited flow screen completion tool for injection wells according to claim 7, characterized in that, After replacing the dedicated solvent, carry out the water injection operation at a displacement of 7.0 barrels per minute.

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