Prepacked sand control screen

Abstract

The application provides a pre-packed sand control screen pipe, and relates to the technical field of oil and gas exploitation. The pre-packed sand control screen pipe comprises a screen pipe base pipe, a screen pipe inner sheath, a screen pipe outer sheath, a first annular end cover, a second annular end cover and pre-packed particles. The screen pipe inner sheath is sleeved on the outside of the screen pipe base pipe, the screen pipe outer sheath is sleeved on the outside of the screen pipe inner sheath, the screen pipe outer sheath is arranged at intervals with the screen pipe inner sheath, the first annular end cover is connected to one end of the screen pipe inner sheath and the screen pipe outer sheath, the second annular end cover is connected to the other end of the screen pipe inner sheath and the screen pipe outer sheath, the screen pipe outer sheath, the screen pipe inner sheath, the first annular end cover and the second annular end cover form a pre-packed chamber, the pre-packed chamber is filled with the pre-packed particles, and the apparent density of the pre-packed particles is less than or equal to 0.8 g / cm 3 . In this way, the frictional resistance between the pre-packed sand control screen pipe and the casing or the well wall when the pre-packed sand control screen pipe is lowered into the well is small.

Description

Technical Field

[0001] This application relates to the field of oil and gas extraction technology, and in particular to a pre-filled sand-proof screen pipe. Background Technology

[0002] Sand screens are an important tool for stabilizing production during oil and gas extraction, used to prevent large-sized sand and gravel from entering production pipelines.

[0003] To improve the sand control effect of sand control screens, a pre-filled sand control screen scheme is proposed. That is, a pre-filled particle layer can be set on the outside of the screen base pipe of the sand control screen. The pre-filled particle layer can be used to block sand and gravel from entering the screen base pipe.

[0004] However, the pre-filled sand screen in the relevant technology has a large frictional resistance between it and the casing or well wall when it is run into the well, which can easily lead to difficulties in running into wells such as extended reach wells and horizontal wells. Summary of the Invention

[0005] This application provides a pre-filled sand control screen to solve the problem of high frictional resistance between the pre-filled sand control screen and the casing or well wall when it is run into the well in related technologies.

[0006] This application provides a pre-filled sand-proof screen pipe, including a screen pipe base pipe, an inner screen pipe sheath, an outer screen pipe sheath, a first annular end cap, a second annular end cap, and pre-filled particles.

[0007] An inner sheath is fitted over the outside of the screen tube base, and an outer sheath is fitted over the outside of the inner sheath. The outer and inner sheaths are spaced apart. A first annular end cap is attached to one end of both the inner and outer sheaths, and a second annular end cap is attached to the other end. A pre-filled chamber is formed between the outer and inner sheaths, the first and second annular end caps, and is filled with pre-filled particles with an apparent density less than or equal to 0.8 g / cm³. 3 .

[0008] The outer sheath of the sieve tube, the inner sheath of the sieve tube, the first annular end cap, and the second annular end cap are used to confine the pre-filled particles within the pre-filled chamber.

[0009] Optionally, the pre-filled particles have a hollow, sealed inner cavity.

[0010] Optionally, the pre-filled particles have a spherical structure.

[0011] Optionally, the outer sheath of the screen tube and the surface of the pre-filled particles have a hydrophobic layer.

[0012] Optionally, the pre-filled sand-proof screen pipe also includes a bypass pipe, which includes a first section, a second section, and a third section distributed along the axial direction of the screen pipe base pipe.

[0013] The second section consists of straight pipe sections spaced axially at both ends of the screen tube base pipe. The second section is fixedly installed in the pre-filled chamber. The first and third sections are inclined pipe sections that are inclined to the axial direction of the screen tube base pipe. The included angles between the first and third sections and the second section are both obtuse angles.

[0014] The outer sheath of the screen tube has a first through hole for the first section to pass through and a second through hole for the third section to pass through. The first section passes through the first through hole and the third section passes through the second through hole.

[0015] One end of the first section is located in the pre-filled chamber and is connected to one end of the second section. The other end of the first section is used to communicate with the space outside the outer sheath of the screen tube.

[0016] One end of the third section is located in the pre-filled chamber and is connected to the other end of the second section. The other end of the third section is used to communicate with the space outside the outer sheath of the screen tube.

[0017] Optionally, the pre-filled sand screen pipe may also include a first soluble plug and a second soluble plug, which dissolve when preset conditions are met.

[0018] The first soluble plug is located at the end of the first section away from the second section. The first soluble plug is used to seal the end of the first section away from the second section. The second soluble plug is located at the end of the third section away from the second section. The second soluble plug is used to seal the end of the third section away from the second section. A sealed chamber is formed between the first soluble plug, the second soluble plug and the inner wall of the bypass pipe.

[0019] Optionally, the cavity formed between the first soluble plug, the second soluble plug, and the inner wall of the bypass pipe is filled with a fluid medium, the density of which is less than 1.0 g / cm³. 3 .

[0020] Optionally, a bypass fastener is fixedly connected to the inner wall of the outer sheath of the screen tube, and the second section is fixedly installed on the inner wall of the outer sheath of the screen tube through the bypass fastener.

[0021] Optionally, the pre-filled particles are fixedly connected to the outer sheath of the screen tube, the second section is in contact with a portion of the pre-filled particles, and the second section is fixedly connected to the contacting pre-filled particles.

[0022] Optionally, the pre-filled sand-proof screen pipe further includes a first connector and a second connector, wherein the first connector is a male connector and the second connector is a female connector. The end of the first annular end cap opposite to the second annular end cap is fixedly connected to the first connector, and the end of the second annular end cap opposite to the first annular end cap is fixedly connected to the second connector. The screen pipe base pipe is fixedly connected to both the first annular end cap and the second annular end cap.

[0023] The pre-filled sand-control screen pipe provided in this application embodiment includes a screen pipe base pipe, an inner screen pipe sheath, an outer screen pipe sheath, a first annular end cap, a second annular end cap, and pre-filled particles. The inner screen pipe sheath is fitted over the outside of the screen pipe base pipe, and the outer screen pipe sheath is fitted over the outside of the inner screen pipe sheath, with the outer screen pipe sheath and the inner screen pipe sheath spaced apart. The first annular end cap is attached to one end of the inner screen pipe sheath and the outer screen pipe sheath, and the second annular end cap is attached to the other end of the inner screen pipe sheath and the outer screen pipe sheath. A pre-filled chamber is formed between the outer screen pipe sheath, the inner screen pipe sheath, the first annular end cap, and the second annular end cap. The pre-filled chamber is filled with pre-filled particles, and the apparent density of the pre-filled particles is less than or equal to 0.8 g / cm³. 3 The outer sheath of the sieve tube, the inner sheath of the sieve tube, the first annular end cap, and the second annular end cap are used to confine the pre-filled particles within the pre-filled chamber.

[0024] With the above setup, after the pre-filled sand-control screen is submerged by formation water, the frictional resistance between the pre-filled sand-control screen and the casing or wellbore is equal to the difference between the weight and buoyancy of the pre-filled sand-control screen multiplied by the coefficient of friction, while the apparent density is less than or equal to 0.8 g / cm³. 3 The pre-filled particles float in formation water. This means that after the pre-filled sand control screen is submerged in formation water, the pre-filled particles provide significant buoyancy. Thus, in addition to improving sand control effectiveness, the increased buoyancy reduces the frictional resistance between the pre-filled sand control screen and the casing or wellbore, making it easier to run in extended reach wells and horizontal wells. Furthermore, reducing the frictional resistance between the pre-filled sand control screen and the casing or wellbore eliminates the need for additional structures, resulting in a simpler and lighter structure for pre-filled sand control screens with lower frictional resistance. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application 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 some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of a pre-filled sand-proof screen pipe provided in an embodiment of this application;

[0027] Figure 2 This is a schematic diagram of the structure of pre-filled particles in a pre-filled sand-control screen provided in an embodiment of this application;

[0028] Figure 3This is a schematic diagram of the structure of another pre-filled sand-proof screen pipe provided in the embodiments of this application;

[0029] Figure 4 for Figure 3 A schematic diagram of the structure of the pre-filled chamber of the pre-filled sand-proof screen pipe;

[0030] Figure 5 This is a schematic diagram of the structure of the pre-filling chamber of another pre-filled sand-proof screen pipe provided in the embodiments of this application.

[0031] Explanation of reference numerals in the attached figures:

[0032] 100. Screen tube base tube; 110. Screen tube aperture;

[0033] 200. Outer sheath of the screen tube;

[0034] 310. First annular end cap; 320. Second annular end cap;

[0035] 400, pre-filled granules;

[0036] 510, First connector; 520, Second connector;

[0037] 600. Pre-filled chamber;

[0038] 700. Inner sheath of the sieve tube;

[0039] 810. Hydrophobic layer; 820. Bypass fastener; 830. First soluble plug; 840. Second soluble plug; 850. Fluid medium;

[0040] 900, bypass pipe; 910, first stage; 920, second stage; 930, third stage. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0042] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0043] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0044] The terms "first," "second," and "third" (if any) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein.

[0045] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or display that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or display.

[0046] As described in the background section, sand control screens are an important tool for stabilizing production during oil and gas extraction. They are commonly used between production pipelines (such as tubing) and casing, or between production pipelines and wellbore, to prevent sand and gravel larger than a certain size from entering the production pipeline. Sand control screens may include a screen base pipe. To improve the sand control effect, a pre-filled sand control screen scheme has been proposed. This means that a pre-filled granular layer can be installed on the outside of the screen base pipe to prevent sand and gravel from entering the screen base pipe.

[0047] In related technologies, the pre-filled particles in the pre-filled particle layer are often gravel, metal particles, or other particles with an apparent density greater than water. After the pre-filled sand control screen is submerged by formation water, the pre-filled particles will carry the screen base pipe down with them. When the pre-filled sand control screen is run into wells such as extended reach wells and horizontal wells, it sinks to the bottom of the formation water and presses against the casing or well wall. The frictional resistance between the pre-filled sand control screen and the casing or well wall is relatively large, and as the well depth increases, the frictional resistance between the pre-filled sand control screen and the casing or well wall will increase. The thrust applied by the derrick to the pre-filled sand control screen will become less effective, resulting in some wells where the pre-filled sand control screen is difficult to run into the predetermined position.

[0048] Figure 1 This is a structural schematic diagram of a pre-filled sand-proof screen tube provided in an embodiment of this application.

[0049] like Figure 1 As shown, based on this, this application provides a pre-filled sand-control screen pipe, which includes a screen pipe base pipe 100, a screen pipe inner sheath 700, a screen pipe outer sheath 200, a first annular end cap 310, a second annular end cap 320, and pre-filled particles 400. An inner sheath 700 is fitted over the outside of the screen tube base tube 100, and an outer sheath 200 is fitted over the outside of the inner sheath 700. The outer sheath 200 and the inner sheath 700 are spaced apart. A first annular end cap 310 is attached to one end of the inner sheath 700 and the outer sheath 200, and a second annular end cap 320 is attached to the other end of the inner sheath 700 and the outer sheath 200. A pre-filled chamber 600 is formed between the outer sheath 200, the inner sheath 700, the first annular end cap 310, and the second annular end cap 320. The pre-filled chamber 600 is filled with pre-filled particles 400, and the apparent density of the pre-filled particles 400 is less than or equal to 0.8 g / cm³. 3 The outer sheath 200, the inner sheath 700, the first annular end cap 310, and the second annular end cap 320 are used to confine the pre-filled particles 400 within the pre-filled chamber 600.

[0050] It should be noted that the screen tube base tube 100 has screen tube orifices 110 for fluid from the pre-filled chamber 600 to flow into the screen tube base tube 100. The screen tube outer sheath 200 has a first connecting hole penetrating the inner and outer walls of the screen tube outer sheath 200. The width of the first connecting hole is smaller than the particle size of the pre-filled particles 400, so that the pre-filled particles 400 cannot flow out of the pre-filled chamber 600 through the first connecting hole. The screen tube inner sheath 700 has a second connecting hole penetrating the inner and outer walls of the screen tube inner sheath 700. The width of the second connecting hole is smaller than the particle size of the pre-filled particles 400, so that the pre-filled particles 400 cannot flow out of the pre-filled chamber 600 through the second connecting hole.

[0051] Thus, after the pre-filled sand-control screen is submerged by formation water, the frictional resistance between the pre-filled sand-control screen and the casing or wellbore is equal to the difference between the weight and buoyancy of the pre-filled sand-control screen multiplied by the coefficient of friction, while the apparent density is less than or equal to 0.8 g / cm³. 3 The pre-filled particles 400 float in formation water. This means that after the pre-filled sand control screen is submerged in formation water, the pre-filled particles 400 provide significant buoyancy. Thus, in addition to improving sand control effectiveness, the increased buoyancy of the pre-filled sand control screen reduces frictional resistance between it and the casing or wellbore, making it easier to run in extended reach wells and horizontal wells. Furthermore, reducing frictional resistance between the pre-filled sand control screen and the casing or wellbore eliminates the need for additional structures, resulting in a simpler and lighter structure for the pre-filled sand control screen with lower frictional resistance.

[0052] Both the outer sheath 200 and the inner sheath 700 of the screen tube can play a certain role in sand control. Fluid in the environment outside the outer sheath 200 of the screen tube can flow into the pre-filling chamber 600 through the first connecting hole on the outer sheath 200 of the screen tube. Larger sand particles in the environment outside the outer sheath 200 of the screen tube are blocked by the outer sheath 200 of the screen tube and cannot be pre-filled into the pre-filling chamber 600 with the fluid. The fluid entering the pre-filling chamber 600 flows to the inner sheath 700 of the screen tube after passing through the gap between the pre-filling particles 400, and then flows into the screen tube orifice 110 through the second connecting hole on the inner sheath 700 of the screen tube. The fluid flowing out from the second connecting hole flows into the screen tube base tube 100 through the screen tube orifice 110.

[0053] The screen base pipe 100 provides structural strength for the pre-filled sand control screen, including bending strength, torsional strength, and tensile and compressive strength. The thrust provided by the derrick for lowering the pre-filled sand control screen into the well is transmitted through the screen base pipe 100. The outer screen sleeve 200 and the inner screen sleeve 700 do not need to provide structural strength for the pre-filled sand control screen. A large number of densely spaced first connecting holes can be formed on the outer screen sleeve 200, and a large number of densely spaced second connecting holes can be formed on the inner screen sleeve 700, which helps improve the efficiency of fluid flow into the screen base pipe 100. Furthermore, after filtration by the outer screen sleeve 200, the pre-filled particles 400, and the inner screen sleeve 700, larger sand and gravel particles are less likely to flow to the screen orifices 110, thus preventing blockage at the screen orifices 110.

[0054] The first annular end cap 310 and the second annular end cap 320 connect the spaced-apart outer sheath 200 and the inner sheath 700 of the screen tube. The first annular end cap 310 and the second annular end cap 320 form the axial boundary of the pre-filled chamber 600 in the screen tube base tube 100, and the outer sheath 200 and the inner sheath 700 form the radial boundary of the pre-filled chamber 600 in the screen tube base tube 100, so as to constrain the pre-filled particles 400 within the pre-filled chamber 600.

[0055] For example, the inner sheath 700 of the sieve tube can be fixedly connected to the first annular end cap 310 and the second annular end cap 320.

[0056] One end of the inner sleeve 700 of the screen tube can be fixedly connected to the first annular end cap 310 by means of snap-fit, fastener connection, threaded connection, etc. The other end of the inner sleeve 700 of the screen tube can be fixedly connected to the second annular end cap 320 by means of snap-fit, fastener connection, threaded connection, etc.

[0057] For example, one end of the inner sleeve 700 of the screen tube is welded and fixed to the first annular end cap 310, and the other end of the inner sleeve 700 of the screen tube is welded and fixed to the second annular end cap 320.

[0058] For example, the outer sheath 200 of the sieve tube can be fixedly connected to the first annular end cap 310 and the second annular end cap 320.

[0059] One end of the outer sheath 200 of the screen tube can be fixedly connected to the first annular end cap 310 by means of snap-fit, fastener connection, threaded connection, etc. The other end of the outer sheath 200 of the screen tube can be fixedly connected to the second annular end cap 320 by means of snap-fit, fastener connection, threaded connection, etc.

[0060] For example, one end of the outer sheath 200 of the screen tube is welded and fixed to the first annular end cap 310, and the other end of the outer sheath 200 of the screen tube is welded and fixed to the second annular end cap 320.

[0061] For example, the sieve tube base tube 100 can be fixedly connected to both the first annular end cap 310 and the second annular end cap 320.

[0062] One end of the screen tube base tube 100 can be fixedly connected to the first annular end cap 310 by means of snap-fit, fastener connection, threaded connection, etc. The other end of the screen tube base tube 100 can be fixedly connected to the second annular end cap 320 by means of snap-fit, fastener connection, threaded connection, etc.

[0063] For example, one end of the screen tube base tube 100 is welded and fixed to the first annular end cap 310, and the other end of the screen tube base tube 100 is welded and fixed to the second annular end cap 320.

[0064] For example, the inner sheath 700 of the screen tube can be fixedly connected to the screen tube base tube 100. In this case, the inner sheath 700 of the screen tube can be fixedly connected to the first annular end cap 310 and the second annular end cap 320 through the screen tube base tube 100.

[0065] For example, the inner sheath 700 of the screen tube can be interference-fitted with the screen tube base tube 100.

[0066] For example, the inner sheath 700 of the screen tube can be bonded and fixed to the outer wall of the screen tube base tube 100.

[0067] For example, one end of the outer sheath 200, the inner sheath 700, and the sieve tube base is fixedly connected to the end face of the first annular end cap 310 facing the second annular end cap 320, and the other end of the outer sheath 200, the inner sheath 700, and the sieve tube base is fixedly connected to the end face of the second annular end cap 320 facing the first annular end cap 310.

[0068] For example, the first annular end cap 310, the second annular end cap 320, the outer sheath 200 of the sieve tube and the sieve tube base tube 100 are coaxially arranged. The inner diameter of the first annular end cap 310 is greater than or equal to the inner diameter of the sieve tube base tube 100, and the inner diameter of the second annular end cap 320 is greater than or equal to the inner diameter of the sieve tube base tube 100.

[0069] For example, the outer sheath 200 of the screen tube may include, but is not limited to, a bridge-type outer sheath, a wire-wound outer sheath, a slit outer sheath, etc.

[0070] For example, the outer sheath 200 of the screen tube can be made of steel, such as L80 steel, N80 steel, P110 steel or 320 steel.

[0071] For example, the inner sheath 700 of the screen tube may include, but is not limited to, a bridge-type outer sheath, a wire-wound outer sheath, a slit outer sheath, etc.

[0072] For example, the inner sleeve 700 of the screen tube can be made of steel, such as L80 steel, N80 steel, P110 steel or 320 steel.

[0073] For example, the screen tube base tube 100 can be made of steel, such as L80 steel, N80 steel, P110 steel or 320 steel.

[0074] For example, the wall thickness of the screen tube base tube 100 is 10-25 mm.

[0075] For example, the shape of the cross-section of the sieve tube aperture 110 may include, but is not limited to, a circle, a square, a racetrack shape, a slit shape, etc.

[0076] In some possible embodiments, the pre-filled sand-control screen pipe further includes a first connector 510 and a second connector 520, wherein the first connector 510 is a male connector and the second connector 520 is a female connector. The first connector 510 and the second connector 520 are respectively fixedly connected to both ends of the screen pipe base pipe 100.

[0077] In some examples where the screen tube base tube 100 is fixedly connected to both the first annular end cap 310 and the second annular end cap 320, the end of the first annular end cap 310 facing away from the second annular end cap 320 is fixedly connected to the first connector 510, and the end of the second annular end cap 320 facing away from the first annular end cap 310 is fixedly connected to the second connector 520.

[0078] This facilitates the connection of multiple pre-filled sand control screens and the connection between the pre-filled sand control screens and structures such as gas seals. The needs of deeper wells can be met by connecting multiple pre-filled sand control screens end to end in sequence.

[0079] The first connector 510 and the second connector 520 can be a pair of matching connectors, that is, the first connector 510 can be used to mate with the second connector 520. In this case, the connection of two pre-filled sand screen pipes can be completed by matet between the first connector 510 of one pre-filled sand screen pipe and the second connector 520 of another pre-filled sand screen pipe.

[0080] In this way, wells of different depths can meet their needs by connecting different numbers of pre-filled sand control screens end to end, and the pre-filled sand control screens have good versatility.

[0081] In some examples, both the first connector 510 and the second connector 520 are threaded connectors.

[0082] In some examples, both the first connector 510 and the second structure are snap-fit ​​connectors.

[0083] Figure 2 This is a schematic diagram of the structure of prefilled particles 400 in a prefilled sand-proof screen tube provided in an embodiment of this application.

[0084] like Figure 2 As shown, in some possible embodiments, the pre-filled particles 400 have a hollow and sealed inner cavity.

[0085] This helps to reduce the apparent density of the pre-filled particles 400, allowing the pre-filled particles 400 to provide greater buoyancy for the pre-filled sand control screen in formation water.

[0086] For example, the pre-filled granules 400 may be made of materials such as glass, ceramics, or styrene polymer resin.

[0087] In some possible implementations, the pre-filled particles 400 have a spherical structure.

[0088] In this way, when the pre-filled chamber 600 is filled with pre-filled particles 400, it facilitates the creation of gaps for fluid flow between the pre-filled particles 400 and between the chamber walls of the pre-filled chamber 600. Furthermore, the curved surface of the pre-filled particles 400 reduces the likelihood of blockage in the gaps between them. Additionally, when the pre-filled particles 400 have a hollow and sealed inner cavity, the stress on the inner and outer walls of the pre-filled particles 400 is more even, making them less prone to deformation due to excessive external water pressure.

[0089] In some possible implementations, the surfaces of the screen tube outer sheath 200 and the pre-filled particles 400 have a hydrophobic layer 810.

[0090] In this way, the hydrophobic layer 810 can prevent the water phase from accumulating, thereby alleviating the accumulation of muddy silt particles, sand particles, etc. carried by the water phase. The screen tube outer sheath 200 and the pre-filled particles 400 are not prone to blockage due to the accumulation of muddy silt particles, sand particles, etc., so that the liquid has good fluidity at the screen tube outer sheath 200 and the pre-filled particles 400, which can improve the seepage capacity between the screen tube outer sheath 200 and the pre-filled particles 400, and help to extend the stable production cycle.

[0091] For example, the hydrophobic layer 810 may be formed from one or more of the following materials: fluorine / silicone materials (such as PTEE, FEP, ECTE, ETFE, fluorinated polyethylene, fluorocarbon wax, fluoropolymers, etc.), other polymer melt polymers (such as polyolefins, polycarbonates, polyamides, polyacrylonitrile, polyesters, fluorine-free acrylates, molten paraffin, etc.), organic-inorganic hybrid hydrophobic coatings (such as alkoxysilanes).

[0092] For example, the surface of the inner sheath 700 of the screen tube may also have a hydrophobic layer 810.

[0093] Figure 3 This is a schematic diagram of the structure of another pre-filled sand-control screen pipe provided in the embodiments of this application. Figure 4 for Figure 3 A schematic diagram of the structure of the pre-filled chamber at position 600 of the pre-filled sand screen pipe.

[0094] like Figure 3 , Figure 4 As shown, in some possible embodiments, the pre-filled sand screen pipe further includes a bypass pipe 900, which includes a first section 910, a second section 920 and a third section 930 distributed axially along the screen pipe base pipe 100.

[0095] The second section 920 is a straight pipe section with both ends axially spaced at intervals on the screen tube base pipe 100. The second section 920 is fixedly installed in the pre-filling chamber 600. The first section 910 and the third section 930 are both inclined pipe sections that are inclined to the axial direction of the screen tube base pipe 100. The included angles between the first section 910, the third section 930 and the second section 920 are both obtuse angles.

[0096] The outer sheath 200 of the screen tube has a first through hole for the first section 910 to pass through and a second through hole for the third section 930 to pass through. The first section 910 passes through the first through hole and the third section 930 passes through the second through hole.

[0097] One end of the first section 910 is located inside the pre-filled chamber 600 and is connected to one end of the second section 920. The other end of the first section 910 is used to communicate with the space outside the screen tube outer sheath 200.

[0098] One end of the third section 930 is located inside the pre-filled chamber 600 and is connected to the other end of the second section 920. The other end of the third section 930 is used to communicate with the space outside the screen tube outer sheath 200.

[0099] Thus, when sand and gravel need to be filled between the outer casing 200 of the screen pipe and the well wall to improve sand control, the problem of formation collapse forming a sand bridge is prone to occur. If formation collapse and sand bridge formation occur, the channel between the outer casing 200 of the screen pipe and the well wall will be blocked. At this time, the sand and gravel can be filled downstream of the blockage location through the bypass pipe 900, which can quickly complete the sand and gravel filling between the outer casing 200 of the screen pipe and the well wall when formation collapse and sand bridge formation occur. In addition, when formation collapse and sand bridge formation do not occur, the bypass pipe 900 increases the passage for filling sand and gravel, which can also improve the efficiency of sand and gravel filling. In addition, the angle between the first section 910 and the second section 920 is an obtuse angle, which facilitates the entry of sand and gravel outside the outer sheath 200 of the screen tube into the second section 920. The angle between the third section 930 and the second section 920 is also an obtuse angle, which facilitates the flow of sand and gravel in the second section 920 through the third section 930 to the outer sheath 200 of the screen tube. The second section 920 is a straight pipe section, which facilitates the passage of sand and gravel through the second section 920 in a shorter time. The passage efficiency of sand and gravel in the bypass pipe 900 is high, and the bypass pipe 900 is not prone to clogging.

[0100] For example, the radial cross-section of the bypass pipe 900 can be racetrack-shaped, elliptical, circular, square, etc.

[0101] For example, the first segment 910 can be interference-fitted with the wall of the first through hole, and the third segment 930 can be interference-fitted with the wall of the second through hole.

[0102] For example, the second segment 920 is parallel to the axial direction of the screen tube base tube 100.

[0103] This facilitates the flow of gravel in the second section 920 and improves the efficiency of filling gravel through the bypass pipe 900.

[0104] In some possible implementations, the pre-filled sand screen pipe further includes a first soluble plug 830 and a second soluble plug 840, which dissolve when preset conditions are met.

[0105] The first soluble plug 830 is disposed at the end of the first segment 910 away from the second segment 920. The first soluble plug 830 is used to seal the end of the first segment 910 away from the second segment 920. The second soluble plug 840 is disposed at the end of the third segment 930 away from the second segment 920. The second soluble plug 840 is used to seal the end of the third segment 930 away from the second segment 920. The first soluble plug 830, the second soluble plug 840 and the inner wall of the bypass pipe 900 form a sealed chamber.

[0106] Thus, before the first soluble plug 830 and the second soluble plug 840 dissolve, a sealed chamber is formed between the first soluble plug 830, the second soluble plug 840, and the inner wall of the bypass pipe 900. This facilitates increased buoyancy of the pre-filled sand screen and reduces frictional resistance between the pre-filled sand screen and the casing or wellbore. After the first soluble plug 830 and the second soluble plug 840 dissolve, the bypass pipe 900 can facilitate the flow of the filling gravel, thereby improving the efficiency of gravel filling.

[0107] After the first soluble plug 830 blocks the end of the first section 910 away from the second section 920, and the second soluble plug 840 blocks the end of the third section 930 away from the second section 920, the sealed chamber formed between the first soluble plug 830, the second soluble plug 840 and the inner wall of the bypass pipe 900 can be filled with air at normal pressure.

[0108] The preset conditions can be one or more of the following: preset interval time, preset temperature, preset pressure, etc.

[0109] For example, the first soluble plug 830 and the second soluble plug 840 can be made of timed dissolution materials (such as aluminum-magnesium alloy, aluminum-magnesium-sulfur alloy, etc.). The first soluble plug 830 and the second soluble plug 840 can start to dissolve in a preset liquid after a preset interval time when a preset temperature condition is reached, and eventually dissolve completely.

[0110] Figure 5 This is a schematic diagram of the structure of the prefilling chamber 600 of another prefilled sand screen pipe provided in the embodiments of this application.

[0111] like Figure 5As shown, in some possible embodiments, the cavity formed between the first soluble plug 830, the second soluble plug 840, and the inner wall of the bypass pipe 900 is filled with a fluid medium 850, the density of which is less than 1.0 g / cm³. 3 .

[0112] In this way, the fluid medium 850 can be used for pressure bearing. When the pressure of the formation water is high, the bypass pipe 900 sealed by the first soluble plug 830 and the second soluble plug 840 is not easily deformed due to excessive external water pressure. At the same time, the fluid medium 850 can also provide buoyancy for the pre-filled sand screen in the formation water to reduce the frictional resistance between the pre-filled sand screen and the casing or well wall.

[0113] The fluid medium 850 can be either a liquid or a gas.

[0114] For example, when the pressure of the formation water is greater than or equal to the pressure that the sealed bypass pipe 900 can withstand, the fluid medium 850 can be a high-pressure gas, such as nitrogen, carbon dioxide, etc.

[0115] For example, the fluid medium 850 can be gasoline.

[0116] In this way, when the pre-filled sand screen is lowered into the oil well, the fluid medium 850 flowing into the formation has little impact on the produced products.

[0117] For example, the fluid medium 850 can be alcohol or methanol.

[0118] In this way, when the pre-filled sand-proof screen is lowered into the hydrate reservoir, the fluid medium 850 flowing into the hydrate reservoir can inhibit the secondary formation of hydrates.

[0119] In some possible implementations, a bypass fastener 820 is fixedly connected to the inner wall of the outer sheath 200 of the screen tube, and the second section 920 is fixedly installed on the inner wall of the outer sheath 200 of the screen tube through the bypass fastener 820.

[0120] This allows the bypass pipe 900 to be fixed more securely within the pre-filled space, resulting in better stability when filling gravel through the bypass pipe 900.

[0121] In some possible implementations, the pre-filled particles 400 are fixedly connected to the outer sheath 200 of the screen tube, and the second section 920 contacts a portion of the pre-filled particles 400, and the second section 920 is fixedly connected to the contacting pre-filled particles 400.

[0122] This reduces the need for bypass fixing parts 820 used to fix the bypass pipe 900, allowing more prefilled particles 400 to be filled into the prefilled chamber 600, which improves the sand control effect and increases the buoyancy of the prefilled sand control screen pipe in the formation water.

[0123] For example, different pre-filled particles 400 can be bonded and fixed together, as well as between the pre-filled particles 400 and the outer sheath 200 of the screen tube.

[0124] For example, different pre-filled particles 400 can be bonded and fixed together, and the whole formed by all the pre-filled particles 400 bonded together can be clamped and fixed by the outer sheath 200 and the inner sheath 700 of the screen tube.

[0125] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A pre-filled sand-proof screen pipe, characterized in that, It includes a screen tube base tube, a screen tube inner sheath, a screen tube outer sheath, a first annular end cap, a second annular end cap, and pre-filled particles; The inner sheath of the sieve tube is fitted over the outside of the sieve tube base tube, and the outer sheath of the sieve tube is fitted over the outside of the inner sheath. The outer sheath and the inner sheath are spaced apart. A first annular end cap is attached to one end of the inner and outer sheaths, and a second annular end cap is attached to the other end. A pre-filled chamber is formed between the outer and inner sheaths, the first and second annular end caps, and the pre-filled chamber is filled with pre-filled particles. The apparent density of the pre-filled particles is less than or equal to 0.8 g / cm³. 3 ; The outer sheath of the sieve tube, the inner sheath of the sieve tube, the first annular end cap, and the second annular end cap are used to confine the pre-filled particles within the pre-filled chamber. The pre-filled sand-proof screen pipe also includes a bypass pipe, which includes a first section, a second section, and a third section distributed along the axial direction of the screen pipe base pipe; One end of the first segment is located in the pre-filled cavity and connected to one end of the second segment, and the other end of the first segment is used to communicate with the space outside the outer sheath of the screen tube. One end of the third segment is located in the pre-filled cavity and connected to the other end of the second segment; the other end of the third segment is used to communicate with the space outside the outer sheath of the screen tube. The pre-filled sand-proof screen pipe also includes a first soluble plug and a second soluble plug, which dissolve when preset conditions are met; The first soluble plug is disposed at the end of the first segment away from the second segment, and the first soluble plug is used to seal the end of the first segment away from the second segment. The second soluble plug is disposed at the end of the third segment away from the second segment, and the second soluble plug is used to seal the end of the third segment away from the second segment. A sealed chamber is formed between the first soluble plug, the second soluble plug and the inner wall of the bypass pipe.

2. The pre-filled sand-proof screen pipe according to claim 1, characterized in that, The pre-filled particles have a hollow and sealed inner cavity.

3. The pre-filled sand-proof screen pipe according to claim 2, characterized in that, The pre-filled particles have a spherical structure.

4. The pre-filled sand-proof screen pipe according to claim 1, characterized in that, The outer sheath of the screen tube and the surface of the pre-filled particles have a hydrophobic layer.

5. The pre-filled sand-proof screen pipe according to claim 1, characterized in that, The second segment is a straight pipe segment with both ends axially spaced on the screen tube base pipe. The second segment is fixedly installed in the pre-filling chamber. The first segment and the third segment are both inclined pipe segments that are inclined to the axial direction of the screen tube base pipe. The included angles between the first segment, the third segment and the second segment are both obtuse angles. The outer sheath of the screen tube has a first through hole for the first section to pass through and a second through hole for the third section to pass through, the first section passing through the first through hole and the third section passing through the second through hole.

6. The pre-filled sand-control screen pipe according to claim 1, characterized in that, The cavity formed between the first soluble plug, the second soluble plug, and the inner wall of the bypass pipe is filled with a fluid medium having a density of less than 1.0 g / cm³. 3 .

7. The pre-filled sand-proof screen pipe according to claim 1, characterized in that, A bypass fixing component is fixedly connected to the inner wall of the outer sheath of the screen tube, and the second section is fixedly installed on the inner wall of the outer sheath of the screen tube through the bypass fixing component.

8. The pre-filled sand-control screen pipe according to claim 1, characterized in that, The pre-filled particles are fixedly connected to the outer sheath of the screen tube, the second section is in contact with a portion of the pre-filled particles, and the second section is fixedly connected to the contacting pre-filled particles.

9. The pre-filled sand-control screen pipe according to any one of claims 1-8, characterized in that, It also includes a first connector and a second connector, wherein the first connector is a male connector and the second connector is a female connector; The end of the first annular end cap opposite to the second annular end cap is fixedly connected to the first connector, and the end of the second annular end cap opposite to the first annular end cap is fixedly connected to the second connector. The screen tube base tube is fixedly connected to both the first annular end cap and the second annular end cap.

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