Sand control screen

Abstract

The present invention provides a sand-proof screen pipe, which relates to the technical field of sand-proof equipment for oil and gas wells; it includes a base pipe and a plurality of ceramic rings sleeved thereon; it also includes a support assembly, the support assembly includes a plurality of brackets arranged in sequence along the axial direction of the base pipe; the bracket includes a base and a barrier sheet connected to each other; the base is located between the base pipe and the ceramic ring so that a first gap is formed between the base pipe and the ceramic ring, and the base is engaged with the inner wall of the ceramic ring; the barrier sheet is inserted between two adjacent ceramic rings so that a second gap is formed between the two adjacent ceramic rings. The present invention generates a gap between the base pipe and the ceramic ring by adding a bracket between the two, and there is no need to weld ribs on the base pipe, which is convenient for production; and the barrier sheets of the bracket are used to generate gaps between adjacent ceramic rings. Since the contact area between the barrier sheets and the ceramic rings is large, multiple barrier sheets can achieve multi-point support, so there will be no roll problem, ensuring the sand-proof performance.

Description

Technical Field

[0001] The invention relates to the technical field of sand control equipment for oil and gas wells, and in particular to a sand control screen pipe. Background Art

[0002] In the process of oil and gas reservoir development, mechanical sand control methods are needed to control sand, and the screen pipe is the core component of mechanical sand control. An existing sand control screen pipe includes a base pipe and a ceramic ring group sleeved outside the base pipe. The ceramic ring group includes a plurality of ceramic rings arranged at intervals along the axial direction of the base pipe. Since the sand control screen pipe needs to allow fluid to pass through, a gap needs to be formed between the ceramic ring and the base pipe, and a gap also needs to be formed between two adjacent ceramic rings.

[0003] At present, the gap between the ceramic ring and the base pipe is formed by welding ribs on the base pipe. The ribs support the ceramic ring to form a gap. This method is relatively cumbersome to process. The gap between two adjacent ceramic rings is formed by two raised structures set on the sides of the ceramic ring. The two raised structures create a gap between the two ceramic rings. This structure easily causes the ceramic ring to tilt, affecting the sand control effect. Summary of the invention

[0004] The object of the present invention is to provide a sand control screen pipe to solve the problems that the existing sand control screen pipe is inconvenient to process and the ceramic ring is prone to tilt.

[0005] In order to solve the above technical problems, the present invention provides a sand control screen pipe, and the specific technical solution is as follows:

[0006] A sand control screen pipe comprises a base pipe and a plurality of ceramic rings sleeved on the base pipe, wherein the plurality of ceramic rings are arranged at intervals along the axial direction of the base pipe; further comprising a support assembly, wherein the support assembly comprises a plurality of brackets arranged in sequence along the axial direction of the base pipe; the brackets comprise a base and a barrier sheet connected to each other; the base is located between the base pipe and the ceramic rings so that a first gap is formed between the base pipe and the ceramic rings, and the base is engaged with the inner wall of the ceramic ring; the barrier sheet is inserted between two adjacent ceramic rings so that a second gap is formed between the two adjacent ceramic rings.

[0007] Furthermore, a plurality of the support assemblies are arranged at intervals along the circumference of the base pipe.

[0008] Furthermore, along the direction away from the base tube, the thickness of the barrier sheet gradually decreases, and the width of the ceramic ring gradually increases.

[0009] Furthermore, in the axial direction of the base tube, two opposite sides of the base are respectively engaged with the inner walls of two adjacent ceramic rings, and two adjacent bases are engaged with the same ceramic ring.

[0010] Furthermore, the base includes two limiting walls arranged in parallel, and the inner wall of the ceramic ring is provided with a protrusion, and the protrusion is engaged between the two limiting walls.

[0011] Furthermore, it also includes two limiting assemblies installed on the base tube, and the plurality of ceramic rings are located between the two limiting assemblies; in the axial direction of the base tube, the ceramic rings located at both ends are fixed to the base tube through the limiting assemblies.

[0012] Furthermore, in the axial direction of the base tube, an elastic member is provided between the ceramic ring at one end or both ends and the limiting assembly.

[0013] Furthermore, the elastic member is a disc spring.

[0014] Furthermore, the limiting assembly includes a pressure ring and a fixing ring; the pressure ring is located outside the ceramic rings at both ends; and the fixing ring is welded to the base tube.

[0015] Furthermore, it also includes a sheath sleeved outside the ceramic ring, and two ends of the sheath are respectively welded to the two pressure rings.

[0016] According to the sand control screen provided by the present invention, a gap is created between the base pipe and the ceramic ring by adding a bracket between the two, and there is no need to weld ribs on the base pipe, which is convenient for production; and a gap is created between adjacent ceramic rings by using the barrier pieces of the bracket. Since the contact area between the barrier pieces and the ceramic rings is large and multiple barrier pieces can achieve multi-point support, there will be no roll problem, thereby ensuring sand control performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of the structure of a sand control screen provided in an embodiment of the present invention;

[0019] Figure 2 for Figure 1 AA section view;

[0020] Figure 3 A schematic diagram of the matching relationship between the support assembly and the ceramic ring provided in an embodiment of the present invention;

[0021] Figure 4 A schematic diagram of the structure of a bracket provided in an embodiment of the present invention.

[0022] icon:

[0023] 1-base tube; 11-first through hole;

[0024] 2-ceramic ring; 21-protrusion;

[0025] 3-support assembly; 31-bracket; 311-base; 3111-limiting wall; 312-barrier;

[0026] 4-limiting assembly; 41-pressing ring; 411-limiting boss; 42-fixing ring;

[0027] 5- elastic member;

[0028] 6-sheath; 61-second through hole. DETAILED DESCRIPTION

[0029] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0031] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] Combined with Figure 1 and 2As shown, this embodiment provides a sand control screen pipe for mechanical sand control in oil and gas reservoir development. The sand control screen pipe includes a base pipe 1 and a plurality of ceramic rings 2 sleeved on the base pipe 1. The plurality of ceramic rings 2 are arranged at intervals along the axial direction of the base pipe 1. The liquid outside the sand control screen pipe flows through the gaps between the ceramic rings 2 and then enters the base pipe 1 through the first through hole 11 on the base pipe 1 to achieve a filtering function. The filtering accuracy is adjusted by adjusting the size of the gaps between adjacent ceramic rings 2.

[0033] Since oil needs to flow through to block the sand body, there is a gap between the ceramic ring 2 and the base pipe 1, and between two adjacent ceramic rings 2 for liquid to flow through. The existing gap generation methods are to process ribs on the base pipe 1 and set bosses on both sides of the ceramic ring 2. However, the processing and welding of the ribs is difficult and the production efficiency is low. The silicon nitride ceramic with high strength and hardness generally used in the ceramic ring 2 is not easy to process, especially the bosses processed to ensure the size of the gap between two adjacent ceramic rings 2. It cannot meet the application of mass production of such sand-proof screens. In addition, due to the difficulty of processing, the bosses on both sides of the existing ceramic ring 2 are generally only one or two, which makes it easy for two adjacent ceramic rings 2 to have the problem of offset and tilting during assembly, resulting in uneven gaps, and even occasional overlap of two bosses, which will increase the gap and affect the filtering accuracy. In view of this, this embodiment improves the structural form of the sand-proof screen and adds a support component 3.

[0034] Combined with Figure 2 and 3 As shown, the support assembly 3 of this embodiment includes a plurality of brackets 31 arranged in sequence along the axial direction of the base tube 1. Two adjacent brackets 31 can be clearance-matched or offset. The material of the bracket 31 of this embodiment is preferably a cemented carbide with good structural strength. It is processed by precision casting and can be mass-produced. In order to achieve a gap between the ceramic ring 2 and the base tube 1 and between two adjacent ceramic rings 2 for liquid to flow through, the bracket 31 of this embodiment includes a connected base 311 and a barrier sheet 312; the base 311 is located between the base tube 1 and the ceramic ring 2, and a first gap is formed between the base tube 1 and the ceramic ring 2 through the base 311, and in order to prevent the bracket 31 from being offset, the base 311 of this embodiment is engaged with the inner wall of the ceramic ring 2, and the base 311 is fixed to a certain position by the ceramic ring 2; the barrier sheet 312 is inserted between two adjacent ceramic rings 2 to form a second gap between the two adjacent ceramic rings 2.

[0035] The above structure creates a gap between the base tube 1 and the ceramic ring 2 by adding a bracket 31 between the two, and there is no need to weld ribs to the base tube 1, which is convenient for production; and the barrier sheet 312 of the bracket 31 creates a gap between adjacent ceramic rings 2. Since the contact area between the barrier sheet 312 and the ceramic ring 2 is large, there is no roll problem, ensuring the sand control performance. Moreover, the gap size between two adjacent ceramic rings 2 can be adjusted by changing the thickness of the barrier sheet 312 through processing, and there is no need to perform mechanical processing on the ceramic, which greatly reduces the workload.

[0036] Combined with Figure 3 As shown, in order to achieve good support for the ceramic ring 2, the present embodiment designs the number of support components 3 to be multiple, and the multiple support components 3 are arranged at intervals along the circumference of the base tube 1. Preferably, they are evenly spaced along the circumference of the base tube 1 to achieve uniform multi-point support for the ceramic ring 2 in the circumferential direction, which can further prevent the ceramic ring 2 from lateral deviation and also improve the installation stability of the ceramic ring 2.

[0037] In order to facilitate the cooperation between the ceramic ring 2 and the barrier sheet 312, the thickness of the barrier sheet 312 of this embodiment gradually decreases in the direction away from the base tube 1, so that the two sides of the barrier sheet 312 form inclined guide surfaces that facilitate the cooperation between the ceramic ring 2. Accordingly, this embodiment also improves the structure of the ceramic ring 2. In the direction away from the base tube 1, the width of the ceramic ring 2 is designed to gradually increase, so that the interval between two adjacent ceramic rings 2 can be well matched with the barrier sheet 312. Moreover, this structure allows two adjacent ceramic rings 2 to form a triangular space when they are superimposed. This structure is not conducive to the accumulation of fine sand inside the gap, but is conducive to faster penetration of oil to obtain a better filtering effect.

[0038] In addition, in order to achieve better matching of the ceramic ring 2, in the axial direction of the base tube 1, the opposite sides of the base 311 of the present embodiment are respectively engaged with the inner walls of two adjacent ceramic rings 2, that is, one base 311 is limited by two ceramic rings 2; and two adjacent bases 311 are engaged with the same ceramic ring 2, that is, one ceramic ring 2 is limited and fixed by two bases 311; the above structure can improve the installation stability of the base 311 while also improving the installation stability of the ceramic ring 2 on the base 311.

[0039] Specifically, there are various ways of clamping the base 311 and the ceramic ring 2 in this embodiment, for example Figure 3 and 4As shown in the figure, the base 311 of the present embodiment includes two parallel limiting walls 3111, and the inner wall of the ceramic ring 2 is provided with a protrusion 21, which is engaged between the two limiting walls 3111. Preferably, a guide surface for facilitating the engagement of the protrusion 21 of the ceramic ring 2 can be provided on the upper part of the limiting wall 3111, so as to facilitate the engagement of the ceramic ring 2 with the base 311. Of course, the engagement connection form between the base 311 and the ceramic ring 2 of the present embodiment is not limited thereto. For example, a protrusion can be provided on the base 311, and a slot can be processed on the ceramic ring 2 to achieve the connection (this method is not shown in the figure). It should be noted that in the present embodiment, the protrusion 21 is processed on the inner wall of the ceramic ring 2, which is obviously easier to process the protrusion 21 on both sides of the ceramic ring 2, because the inner wall size of the ceramic ring 2 is much larger than the thickness size of the two sides of the ceramic ring 2, so it will not affect the production efficiency.

[0040] Preferably, in order to facilitate processing, the material of the ceramic ring 2 of this embodiment is alumina ceramic. This ceramic product has good mechanical strength and high temperature resistance, a simpler production process than silicon nitride, better processing performance than silicon nitride, and is also more convenient to prepare and process.

[0041] In addition, in order to achieve the fixation of multiple ceramic rings 2, the sand control screen pipe of this embodiment also includes two limit assemblies 4 installed on the base pipe 1, and the multiple ceramic rings 2 are located between the two limit assemblies 4; in the axial direction of the base pipe 1, the ceramic rings 2 located at both ends are fixed to the base pipe 1 through the two limit assemblies 4 to achieve the fixation of the ceramic rings 2.

[0042] Based on the above-mentioned limit assembly 4, the inventor found that the existing limit structure is generally connected and fixed to the base pipe 1 by welding, and the ceramic ring 2 is compressed by a threaded connection. The pressure on the ceramic ring 2 is adjusted by adjusting the thread, and the ceramic ring 2 cannot be compressed and adjusted adaptively. Therefore, the connection structure of the limit assembly 4 and the ceramic ring 2 is improved in this embodiment. In the axial direction of the base pipe 1, an elastic member 5 is provided between the ceramic ring 2 and the limit assembly 4 at one or both ends. The elastic member 5 is respectively connected to the ceramic ring 2 and the limit assembly 4. Through the elastic deformation of the elastic member 5, the compression force between the limit assembly 4 and the ceramic ring 2 can be adaptively adjusted during the sand filtering process. Preferably, the elastic member 5 of this embodiment is a disc spring, which has the advantages of short stroke, small installation space, easy maintenance and replacement, etc., and is very suitable for the sand control screen pipe of this embodiment.

[0043] Specifically, the limiting assembly 4 of this embodiment includes a pressure ring 41 and a fixing ring 42; the pressure ring 41 of this embodiment is located on the outside of the ceramic rings 2 at both ends, and the above-mentioned elastic member 5 can be arranged between the pressure ring 41 and the ceramic ring 2; the fixing ring 42 of this embodiment is welded on the base pipe 1 to improve the stability of the connection.

[0044] Based on the above structure, the inventor found that when the ceramic sand filter tube is transported or lowered into the oil well, the ceramic ring 2 is easily bumped due to the lack of a protective structure on the outside of the ceramic ring 2, causing the ceramic ring 2 to break, which directly affects the filtering accuracy. If the damaged sand filter tube is continued to be lowered into the well without knowing it, it will cause serious sand leakage and sand carrying accidents, directly affecting the oil production quality. Therefore, this embodiment further improves the structure of the sand screen tube, and adds a sheath 6 thereon, which is sleeved outside the ceramic ring 2, and the two ends of the sheath 6 are respectively welded to the two pressure rings 41.

[0045] Specifically, the outer wall of the pressure ring 41 of this embodiment is provided with a limiting boss 411, and the two ends of the sheath 6 are clamped between the two limiting bosses 411 of the two pressure rings 41. The strength and rigidity of the material of the sheath 6 of this embodiment can be greater than the strength and rigidity of the ceramic ring 2 of this embodiment, such as metal or alloy material. Many second through holes 61 are evenly distributed on the sheath 6 of this embodiment for oil to flow through. The main purpose of the sheath 6 is to protect the ceramic ring 2. When transporting or going down the well, it can effectively prevent the ceramic ring 2 from being bumped and broken, greatly reducing the sand leakage accident.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A sand control screen pipe, comprising a base pipe and a plurality of ceramic rings sleeved on the base pipe, wherein the plurality of ceramic rings are arranged at intervals along the axial direction of the base pipe; characterized in that: It also includes a support assembly, which includes a plurality of brackets arranged in sequence along the axial direction of the base pipe; The support comprises a base and a barrier sheet connected to each other; the base is located between the base tube and the ceramic ring so that a first gap is formed between the base tube and the ceramic ring, and the base is engaged with an inner wall of the ceramic ring; The barrier sheet is inserted between two adjacent ceramic rings to form a second gap between the two adjacent ceramic rings; In a direction away from the base tube, the thickness of the barrier sheet gradually decreases, and the width of the ceramic ring gradually increases, so that one side of the barrier sheet forms an inclined guide surface that is convenient for the ceramic ring to fit; In a direction away from the base tube, the width of the ceramic ring gradually increases, so that the interval between two adjacent ceramic rings can match the barrier sheet; In the axial direction of the base tube, opposite sides of the base are respectively engaged with the inner walls of two adjacent ceramic rings, and two adjacent bases are engaged with the same ceramic ring.

2. The sand control screen according to claim 1, characterized in that: A plurality of the support assemblies are arranged at intervals along the circumference of the base pipe.

3. The sand control screen according to claim 1, characterized in that: The base comprises two limiting walls arranged in parallel, and the inner wall of the ceramic ring is provided with a protrusion, which is engaged between the two limiting walls.

4. The sand control screen according to any one of claims 1 to 3, characterized in that: It also includes two limiting components installed on the base tube, and the plurality of ceramic rings are located between the two limiting components; in the axial direction of the base tube, the ceramic rings located at both ends are fixed to the base tube through the limiting components.

5. The sand control screen according to claim 4, characterized in that: In the axial direction of the base tube, an elastic member is provided between the ceramic ring at one end or both ends and the limiting assembly.

6. The sand control screen according to claim 5, characterized in that: The elastic member is a disc spring.

7. The sand control screen according to claim 4, characterized in that: The limiting assembly comprises a pressure ring and a fixing ring; the pressure ring is located outside the ceramic rings at both ends; and the fixing ring is welded on the base tube.

8. The sand control screen according to claim 7, characterized in that: It also includes a sheath sleeved outside the ceramic ring, and two ends of the sheath are respectively welded to the two pressure rings.

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