Sand control screen pipe, well completion tool and floating screen pipe descending method

Abstract

The invention discloses a sand control screen pipe, a well completion tool and a floating screen pipe lowering method, and relates to the technical field of oil and gas well exploitation. The sand control screen pipe comprises a plurality of plugs, a central pipe, a sand control filter layer and a protective sleeve, the central pipe, the sand control filter layer and the protective sleeve are sequentially arranged from inside to outside in a sleeved mode, a plurality of through holes are formed in the pipe wall of the central pipe, the plugs are inserted into the corresponding through holes and matched with the corresponding through holes in a sealed mode, the plugs are alloy parts which can be dissolved through dissolving liquid, and the sand control screen pipe can be put in place conveniently. When the sand control screen pipe is used for well completion, the construction period is short, and operation is easy and convenient.

Description

Technical Field

[0001] This invention relates to the field of oil and gas well development technology, and more specifically, to a sand control screen. Furthermore, this invention also relates to a well completion tool comprising the aforementioned sand control screen. Moreover, this invention further relates to a floating screen lowering method suitable for the aforementioned sand control screen. Background Technology

[0002] In extended reach wells, especially extended reach horizontal wells, sand control screens are commonly used for open hole mechanical sand control completion in the target formation. This technology can avoid the pollution of the reservoir caused by cementing slurry, and at the same time save a lot of perforation and in-tube sand control operation costs. However, when using sand control screens for completion, the friction of running the sand control screens is usually large, which may result in the tubing not being able to be run smoothly into place, affecting the completion effect.

[0003] In summary, ensuring that the sand-proof screen pipe can be properly installed is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a sand-proof screen tube that is easy to be installed in place.

[0005] Another object of the present invention is to provide a well completion tool including the above-described sand control screen.

[0006] Another object of the present invention is to provide a floating screen tube method applicable to the above-mentioned sand-proof screen tube.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A sand-proof screen pipe includes: several plugs, a central pipe arranged sequentially from the inside to the outside, a sand-proof filter layer, and a protective sleeve;

[0009] The central tube has several through holes in its wall, and several plugs are inserted into the corresponding through holes and are sealed to each other. The plugs are alloy parts that can be dissolved by a dissolving liquid.

[0010] Preferably, the plug is an aluminum-magnesium alloy component.

[0011] Preferably, a plurality of the plugs are threadedly connected to the corresponding through holes, and the space between the plugs and the corresponding through holes is filled with sealant.

[0012] Preferably, the through hole extends radially along the central tube.

[0013] Preferably, the plug comprises a coaxial first column segment and a second column segment;

[0014] The circumferential surface of the first column segment has external threads to mate with the corresponding through hole threads;

[0015] The diameter of the second column segment is larger than that of the first column segment, and the second column segment abuts against the inner wall of the central tube.

[0016] Preferably, one end of the first column segment is connected to the second column segment, and the other end of the first column segment extends to the outer wall of the central tube.

[0017] Preferably, it also includes a storage tank filled with the solution.

[0018] A well completion tool, comprising the sand control screen provided by any of the above, and further comprising a tailpipe hanger, a floating coupling and a bottom packing tool;

[0019] The tailpipe hanger, the floating coupling, and the sand screen can be connected in sequence, and the bottom filling tool can be connected to the second end of the sand screen to seal the second end of the sand screen.

[0020] A method for floating screen pipes, applied to the sand control screen pipes provided in any of the above claims, the method comprising:

[0021] The tailpipe hanger, floating coupling, sand screen, and bottom filling tool are connected in sequence to form a well completion tool;

[0022] Connect the tailpipe hanger to the tail end of the accompanying drill pipe and lower the completion tools into the well.

[0023] A dissolving solution is injected into the sand control screen tube to dissolve the plug of the sand control screen tube.

[0024] The sand-proof screen tube provided by the present invention consists of a central tube, a sand-proof filter layer and a protective sleeve arranged sequentially from the inside to the outside. The wall of the central tube has through holes so that the space between the central tube and the protective sleeve can be connected to the inner cavity of the central tube, and sand prevention can be achieved through the sand-proof filter layer.

[0025] The beneficial effect is that corresponding plugs are inserted in several through holes in the wall of the central tube, with interference fit or threaded fit, and the plugs can be dissolved by the dissolving liquid. When using this sand control screen pipe for well completion, the screen pipe is first lowered into the well, and then the dissolving liquid is injected into the inner cavity of the central tube to dissolve the plugs set in the central tube to achieve well completion. The sand control screen pipe has low lowering friction, which helps to ensure that it is lowered into place. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0027] Figure 1 This is a partial structural diagram of a specific embodiment provided by the present invention;

[0028] Figure 2 This is a schematic diagram illustrating the use of a specific embodiment of the present invention.

[0029] Figure label:

[0030] 1-Central tube; 2-Sand filter layer; 3-Protective sleeve; 4-Plug; 41-First column section; 42-Second column section.

[0031] 10-Sand screen pipe; 20-Tailpipe hanger; 30-Floating coupling; 40-Bottom filling tool;

[0032] 100 - Accompanying drill pipe. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] The core of this invention is to provide a sand-control screen pipe that is easy to lower into place. Another core of this invention is to provide a well completion tool including the aforementioned sand-control screen pipe. Yet another core of this invention is to provide a floating screen pipe lowering method applicable to the aforementioned sand-control screen pipe.

[0035] Please refer to Figure 1 The present invention provides a sand-proof screen pipe, comprising a plurality of plugs 4, a central tube 1, a sand-proof filter layer 2 and a protective sleeve 3 arranged sequentially from the inside to the outside, wherein the wall of the central tube 1 has a plurality of through holes, and a plurality of plugs 4 are inserted into the corresponding through holes and sealed with the corresponding through holes, and the plugs 4 are alloy parts that can be dissolved by a dissolving liquid.

[0036] The central tube 1, the sand-proof filter layer 2, and the protective sleeve 3 are sequentially arranged from the inside to the outside. The wall of the central tube 1 has a through hole so that the space between the central tube 1 and the protective sleeve 3 can be connected to the inner cavity of the central tube 1. Sand prevention can be achieved through the sand-proof filter layer 2 sandwiched between the central tube 1 and the protective sleeve 3.

[0037] The central tube 1 has several through holes in which corresponding plugs 4 are inserted, with interference fit or threaded fit, and the plugs 4 can be dissolved by a dissolving liquid. When using this sand control screen for well completion, the screen is first lowered into the well, and then the dissolving liquid is injected into the inner cavity of the central tube 1 to dissolve the plugs 4 in the central tube 1, restoring the flowability of the sand control screen and achieving well completion. The sand control screen has low friction when lowered, which helps to ensure that it is lowered into place. When using this sand control screen for well completion, there is no need to use a well washing string for acid washing. Well washing can be carried out directly after using this sand control screen for well completion. Therefore, using this sand control screen is advantageous for a shorter construction period and simpler operation.

[0038] It should be noted that the shape of the through hole and the plug 4 is not limited. For example, the through hole can be a cylindrical through hole or a frustum-shaped through hole, and the plug 4 can be inserted into and fitted into the corresponding through hole. It should also be noted that the extension direction of the through hole is not limited. For example, it can be along the radial direction of the central tube 1 or have an acute angle with the axial direction of the central tube 1, as long as it can connect the inner cavity of the central tube 1 with its outer side.

[0039] It should also be noted that there are no restrictions on the type of plug 4 and the dissolving liquid, as long as the strength of plug 4 is guaranteed and the dissolving liquid can dissolve plug 4. For example, plug 4 can be made of gallium aluminum zinc alloy. When in use, a solution of nitric acid or hydrochloric acid is injected into the central tube 1 to dissolve plug 4.

[0040] Based on the above embodiment, the plug 4 is made of aluminum-magnesium alloy. In use, a solution containing chloride ions is injected into the central tube 1 to dissolve the plug 4. With this configuration, the cost of the sand-proof screen pipe is relatively low.

[0041] Based on the above embodiment, a plurality of plugs 4 are threadedly connected to corresponding through holes, and the space between the plugs 4 and the corresponding through holes is filled with sealant.

[0042] The inner wall of the through hole is threaded, and the outer circumferential surface of the plug 4 is also threaded, so that several plugs 4 can be screwed into the corresponding through hole. The space between the outer circumferential surface of the plug 4 and the inner wall of the corresponding through hole is filled with sealant to ensure the sealing performance of the plug 4 to the through hole and the pressure bearing capacity of the plug 4.

[0043] Based on the above embodiment, the through hole extends radially along the central tube 1, which helps to reduce the manufacturing difficulty of the sand screen tube while ensuring the pressure bearing capacity of the plug 4.

[0044] Based on the above embodiment, the plug 4 includes a coaxial first column segment 41 and a second column segment 42; the circumferential surface of the first column segment 41 has external threads to mate with the corresponding through hole threads; the diameter of the second column segment 42 is larger than the diameter of the first column segment 41, and the second column segment 42 abuts against the inner wall of the central tube 1.

[0045] like Figure 1 As shown, the plug 4 has a stepped columnar structure. The first column section 41 is cylindrical, and the outer circumferential surface of the first column section 41 is threaded to fit with the through hole. The diameter of the first column section 41 is smaller than the diameter of the second column section 42. The second column section 42 can be cylindrical or hexagonal prism, etc. After the plug 4 is screwed into the corresponding through hole, the second column section 42 abuts against the inner wall of the central tube 1. This arrangement facilitates further improvement of the pressure-bearing capacity of the plug 4.

[0046] Based on the above embodiment, one end of the first column segment 41 is connected to the second column segment 42, and the other end of the first column segment 41 extends to the outer wall of the central tube 1, so as to ensure the pressure bearing capacity of the plug 4 while preventing damage to the sand filter layer 2.

[0047] Based on the above embodiments, a storage tank filled with a dissolving solution is also included, so that the dissolving solution in the storage tank can be used for well completion during construction.

[0048] Based on the above embodiments, the central tube 1 has a sensing structure. For example, the central tube 1 is made of magnetized ferromagnetic steel pipe, or the outer circumferential surface of the central tube 1 is coated with magnetic powder. The sensing structure, together with the detection structure, can detect the central tube 1 to determine whether the plug 4 has been completely dissolved.

[0049] In addition to the aforementioned sand control screen, the present invention also provides a well completion tool including the sand control screen 10 disclosed in the above embodiments. The well completion tool further includes a tailpipe hanger 20, a floating coupling 30, and a bottom filling tool 40. The tailpipe hanger 20, the floating coupling 30, and the sand control screen 10 can be sequentially connected. The bottom filling tool 40 can be connected to the second end of the sand control screen 10 to seal the second end of the sand control screen 10.

[0050] The tailpipe hanger 20, the floating coupling 30, and the aforementioned sand screen 10 are all hollow tubular structures. The tailpipe hanger 20 and the floating coupling 30 are both joint structures. The left end of the tailpipe hanger 20 can be connected to the accompanying drill rod 100, and the right end can be connected to the left end of the floating coupling 30, such as by plugging or threading. The right end of the floating coupling 30 can be connected to the left end of the aforementioned sand screen 10, such as by plugging or threading. The right end of the aforementioned sand screen 10 can be equipped with a bottom filling tool 40, such as by plugging or threading, to seal the right end of the sand screen 10.

[0051] In addition to the aforementioned sand control screen 10 and well completion tools, the present invention also provides a floating screen method applicable to the sand control screen 10 disclosed in the above embodiments, the floating screen method comprising the following steps:

[0052] S1: Connect the tailpipe hanger 20, floating coupling 30, sand screen 10 and bottom filling tool 40 in sequence to form a well completion tool; in this step, the well completion tool is pre-assembled before the well completion operation.

[0053] S2: Connect the tailpipe hanger 20 to the tail end of the accompanying drill pipe 100 and lower the completion tool into the well; in this step, the completion tool is installed on the end of the accompanying drill pipe 100 so that the completion tool is lowered into the well under the pushing of the accompanying drill pipe 100.

[0054] S3: Inject dissolving liquid into the sand control screen 10 to dissolve the plug 4 of the sand control screen 10; in this step, dissolving liquid is injected into the sand control screen 10 to dissolve the plug 4, thereby restoring the flowability of the sand control screen 10 to achieve well completion.

[0055] It should be noted that the relational terms such as "first" and "second" mentioned above are only used to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities; the terms "upper surface," "lower surface," "top," and "bottom" and the directional terms "upper," "lower," "left," and "right" mentioned above are defined based on the accompanying drawings in the specification.

[0056] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0057] The sand control screen, well completion tool, and floating screen lowering method provided by this invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. It should be noted that those skilled in the art can make several improvements and modifications to this invention without departing from the principles of this invention, and these improvements and modifications also fall within the protection scope of this invention.

Claims

1. A sand-proof screen pipe, characterized in that, include: Several plugs (4), a central tube (1), a sand-proof filter layer (2) and a protective sleeve (3) are installed sequentially from the inside to the outside; The central tube (1) has several through holes in its wall, and several plugs (4) are inserted into the corresponding through holes and are sealed to the corresponding through holes. The plugs (4) are alloy parts that can be dissolved by a dissolving liquid.

2. The sand-proof screen pipe according to claim 1, characterized in that, The plug (4) is an aluminum-magnesium alloy part.

3. The sand-proof screen pipe according to claim 1, characterized in that, Several of the plugs (4) are threadedly connected to the corresponding through holes, and the space between the plugs (4) and the corresponding through holes is filled with sealant.

4. The sand-proof screen pipe according to claim 3, characterized in that, The through hole extends radially along the central tube (1).

5. The sand-proof screen pipe according to claim 4, characterized in that, The plug (4) includes a coaxial first column segment (41) and a second column segment (42). The circumferential surface of the first column segment (41) has external threads to mate with the corresponding through hole threads; The diameter of the second column segment (42) is greater than the diameter of the first column segment (41), and the second column segment (42) abuts against the inner wall of the central tube (1).

6. The sand-proof screen pipe according to claim 5, characterized in that, One end of the first column segment (41) is connected to the second column segment (42), and the other end of the first column segment (41) extends to the outer wall of the central tube (1).

7. The sand-proof screen pipe according to claim 1, characterized in that, It also includes a storage tank filled with the solution.

8. A well completion tool, characterized in that, The sand screen pipe (10) as described in any one of claims 1-7 further includes a tailpipe hanger (20), a floating coupling (30), and a bottom filling tool (40). The tailpipe hanger (20), the floating coupling (30), and the sand screen pipe (10) can be connected in sequence, and the bottom filling tool (40) can be connected to the second end of the sand screen pipe (10) to seal the second end of the sand screen pipe (10).

9. A method for floating a screen tube, characterized in that, Applied to the sand-control screen pipe (10) according to any one of claims 1 to 7, the floating screen pipe method includes: The tailpipe hanger (20), floating coupling (30), sand screen pipe (10) and bottom filling tool (40) are connected in sequence to form a well completion tool; Connect the tailpipe hanger (20) to the tail end of the accompanying drill pipe (100) and lower the completion tool into the well; A dissolving solution is injected into the sand screen tube (10) to dissolve the plug (4) of the sand screen tube (10).

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