Eccentric water distributor

Abstract

The utility model discloses an eccentric water distributor which comprises an eccentric upper connector, an eccentric lower connector and a connecting sleeve, centralizing bodies are sequentially installed in the connecting sleeve from top to bottom, and each centralizing body is an eccentric pipe body composed of an iron cylinder coaxial with the outer wall of an eccentric main body and a pipe hole coaxial with a main channel of the eccentric main body in the iron cylinder. The thick wall side of the eccentric pipe body is provided with a throwing and fishing tool release guide straight notch corresponding to the position of a blanking plug installation hole, the eccentric pipe body is cut into an open eccentric pipe body with a C-shaped section through the throwing and fishing tool release guide straight notch, and a stainless steel lining layer is arranged on the inner wall of a pipe hole of the open eccentric pipe body. A conical guide pipe opening coaxial with the iron cylinder is formed in the upper end of the open eccentric pipe body. The inner wall of the pipe hole of the centralizer body of the eccentric water distributor is high in hardness and good in smoothness, the centralizer body is not prone to scaling when working in a sand-containing well for a long time, scratches hindering normal operation of a throwing-fishing tool cannot be formed on the inner wall of the pipe hole of the centralizer body even if the throwing-fishing tool works repeatedly, and the success rate of throwing-fishing operation of the blanking plug is high.

Description

Technical Field

[0001] This utility model relates to a downhole injector for oilfield water injection tubing, and more particularly to an eccentric water distributor. Background Technology

[0002] An eccentric water distributor is a specialized tool used for downhole water injection in oilfields, primarily for controlling the water flow distribution in injection wells. During water volume adjustment, a dedicated retrieval tool is needed to deploy a plug into the plug mounting hole of the eccentric water distributor, or to retrieve a plug installed in the mounting hole. To ensure the plug aligns with the mounting hole, a centralizer is installed within the eccentric water distributor to guide the retrieval tool. Theoretically, the smaller the clearance between the centralizer and the retrieval tool, the more precise the plug's placement. However, prolonged operation downhole causes slight corrosion on the centralizer's surface, increasing surface roughness and leading to scale buildup. Scale buildup reduces the diameter of the centralizer's orifice and decreases its smoothness, making it prone to jamming the retrieval tool and hindering plug deployment or retrieval. In severe cases, it can render the water distributor unusable. To overcome the drawbacks of corrosion and scaling on the inner wall of the stabilizer tube, some eccentric water distributors use engineering plastics such as polyphenylene sulfide (PPS) to produce the stabilizer. Although PPS can solve the corrosion and scaling problems of the stabilizer, the PPS stabilizer has low hardness. When used in water injection operations in sandy wells, scratches will form on the inner wall of the PPS stabilizer tube after repeated operations. The scratches will damage the smoothness of the inner wall of the tube. Deeper scratches can also cause the retrieval claw and guide claw of the blocker to get stuck during the retrieval of the tool, making it impossible to operate normally and resulting in the failure of the retrieval operation. Utility Model Content

[0003] The technical problem to be solved by the utility model is to overcome the above-mentioned defects of the existing technology and provide an eccentric water distributor. The inner wall of the centralizing body of the eccentric water distributor has high hardness and good smoothness. The centralizing body is not prone to scaling when working in sandy wells for a long time. The fishing tool will not form scratches on the inner wall of the centralizing body's pipe hole after repeated operations, which will hinder the normal operation of the fishing tool. The success rate of the fishing operation of the blocker is high.

[0004] The technical solution adopted to solve the technical problem is as follows: An eccentric water distributor includes an eccentric upper connector, an eccentric lower connector, and a connecting sleeve whose two ends are respectively threaded to the eccentric upper and lower connectors and the eccentric lower connector. Inside the connecting sleeve, from top to bottom, are a centering body, an eccentric main body, and an axial positioning sleeve. A circumferential guide body is installed inside the lower connector. The eccentric main body has a main channel and a plug mounting hole. A water distribution hole is provided on the wall of the plug mounting hole. Sealing devices that slide and seal with the connecting sleeve are provided on the outer walls of the eccentric main body on the upper and lower sides of the water distribution hole. A water injection hole is provided at the corresponding water distribution hole position of the connecting sleeve. The centering body is an eccentric tube body composed of an iron column coaxial with the outer wall of the eccentric body and a pipe hole coaxial with the main channel of the eccentric body inside the iron column. A release guide straight groove for the retrieval tool is opened on the thick wall side of the eccentric tube body, corresponding to the position of the blocker installation hole. The release guide straight groove for the retrieval tool cuts the eccentric tube body into an open eccentric tube body with a C-shaped cross section. A stainless steel inner lining layer is provided on the inner wall of the pipe hole of the open eccentric tube body. A tapered guide pipe opening coaxial with the iron column is provided at the upper end of the open eccentric tube body.

[0005] As a further improvement of this utility model: the stainless steel inner lining is a stainless steel liner that corresponds to the shape of the inner wall of the eccentric tube hole, and the stainless steel liner is welded to the eccentric tube.

[0006] As a further improvement of this utility model: multiple welding holes are drilled along the radius of the pipe hole on the eccentric tube body, a stainless steel liner is welded and fixed to the eccentric tube body at the bottom of the welding holes, a non-metallic insulating layer is filled between the stainless steel liner and the eccentric tube body, and sealant is filled in the welding holes.

[0007] As a further improvement of this utility model, the thickness of the stainless steel inner lining layer is not less than 1 mm.

[0008] As a further improvement of this utility model: the outer wall of the lower end of the positioning sleeve is provided with a positioning sleeve axial position adjustment thread that mates with the thread of the inner wall of the connecting sleeve.

[0009] As a further improvement of this utility model: a fixing screw hole is provided on the circumferential guide body, and a circumferential guide body positioning screw hole is provided on the lower connector, and a guide body fixing screw is installed in the guide body positioning screw hole.

[0010] As a further improvement of this utility model: at the lower end of the release guide straight groove of the stabilizing body, there is a guide claw retraction guide rail that retracts the guide claw of the stabilizing body. The guide claw retraction guide rail protrudes from the wall surface of the release guide straight groove of the stabilizing body, and the angle between the rail surface of the guide claw retraction guide rail and the axis of the inner wall of the pipe hole is 18 degrees.

[0011] As a further improvement of this utility model, an eccentric main body fixing screw is provided on the connecting sleeve.

[0012] Beneficial effects: The eccentric water distributor of this utility model, due to the technical feature of having a stainless steel inner lining layer on the inner wall of the pipe hole of the open eccentric pipe body, improves the hardness, smoothness and corrosion resistance of the inner wall of the centralizing body pipe hole. This makes it less prone to scaling when the centralizing body of the eccentric water distributor of this utility model works for a long time in sandy wells. Even after multiple operations of the retrieval tool, no scratches will be formed on the inner wall of the centralizing body pipe hole that would hinder the normal operation of the retrieval tool. The inner wall of the centralizing body pipe hole can always maintain a high degree of smoothness, and the success rate of the blocker retrieval operation is high. The adoption of a conical guide port coaxial with the iron column at the upper end of the open eccentric pipe allows the guide claw at the lower end of the retrieval tool to automatically rotate under the guidance of the conical guide port's slope when entering the centralizing body from the upper connector. This allows it to quickly and accurately enter the release guide slot of the retrieval tool, ensuring that the blocker's retrieval claw aligns with the release guide slot before entering the centralizing body. This guarantees the timely ejection of the blocker's retrieval claw within the release guide slot, further improving the success rate of blocker retrieval operations. Furthermore, the use of a stainless steel liner that corresponds to the shape of the inner wall of the open eccentric pipe's bore, welded to the eccentric pipe body, simplifies the manufacturing process and reduces production costs while ensuring performance. By employing a technique that involves drilling multiple welding holes along the radius of the eccentric tube, welding a stainless steel liner to the eccentric tube at the bottom of these holes, filling the space between the liner and the tube with a non-metallic insulating layer, and filling the welding holes with sealant, this design overcomes the defect of bimetallic corrosion that occurs when stainless steel is welded to ordinary steel. This results in stronger corrosion resistance for the centralizing body and a longer service life for the eccentric water distributor. The reasonably limited thickness of the stainless steel liner balances the cost and performance of the centralizing body. The use of a positioning sleeve with an axial position adjustment thread on the lower outer wall that engages with the inner wall of the connecting sleeve allows for easy adjustment of the axial position of the eccentric body within the connecting sleeve by simply turning the positioning sleeve, meeting the requirements of different plugs. Furthermore, the inclusion of a fixing screw hole on the circumferential guide body and a positioning screw hole on the lower connector, with a fixing screw installed within the positioning screw hole, prevents the circumferential guide body from rotating during use and causing the plug to fail to accurately enter its position, thus enhancing the reliability of this eccentric water distributor. Because of the technical feature of having a guide claw retraction rail at the lower end of the release guide straight groove of the retrieval tool on the straight groove of the stabilizing body, which allows the guide claw of the retrieval tool to retract inward, and the guide claw retraction rail protruding from the wall surface of the release guide straight groove of the retrieval tool, and the angle between the rail surface of the guide claw retraction rail and the axis of the inner wall of the pipe hole being 18 degrees, the guide claw of the blocker can retract into the retrieval tool after entering the release guide straight groove of the retrieval tool, smoothly pass through the main channel of the eccentric body, and reach the circumferential guide body.Because of the technical feature of having an eccentric main body fixing screw on the connecting sleeve, the position of the eccentric main body can be prevented from changing during the retrieval of the blocker, thus affecting the next retrieval operation. Attached Figure Description

[0013] The eccentric water distributor of this utility model will be further described in detail below with reference to the accompanying drawings.

[0014] Figure 1 This is an axial cross-sectional view of the eccentric water distributor of this utility model;

[0015] Figure 2 This is a three-dimensional view of the centralizing body in the eccentric water distributor of this utility model;

[0016] Figure 3 This is a cross-sectional view of the centralizing body in the eccentric water distributor of this utility model. Detailed Implementation

[0017] like Figure 1 As shown, the eccentric water distributor of this utility model includes an eccentric upper connector 1, an eccentric lower connector 13, and a connecting sleeve 3 whose two ends are respectively threaded to the eccentric upper and lower connectors and the eccentric lower connector. Inside the connecting sleeve, from top to bottom, are a centering body 4, an eccentric main body 18, and an axial positioning sleeve 11. A circumferential guide body 12 is installed inside the lower connector. The eccentric main body has a main channel 17 and a plug mounting hole 7. A water distribution hole 9 is provided on the wall of the plug mounting hole. The outer walls of the eccentric main body on the upper and lower sides of the water distribution hole are provided with sliding sealing mechanisms that cooperate with the connecting sleeve. The sealing device consists of a sealing ring 8 embedded in the sealing ring groove on the outer wall of the eccentric body. A water injection hole 10 is provided at the corresponding water distribution hole position on the connecting sleeve. An axial position adjustment thread for the positioning sleeve is provided on the outer wall of the lower end of the positioning sleeve, which engages with the threaded inner wall of the connecting sleeve. The circumferential guide is a pen-tip shaped guide with a fixing screw hole. A circumferential guide positioning screw hole is provided on the lower connector, and a guide fixing screw 20 is installed in the guide positioning screw hole. An eccentric body fixing set screw 19 is provided on the connecting sleeve. The centering body is an eccentric tube composed of an iron column 14 coaxial with the outer wall of the eccentric body and a pipe hole 16 coaxial with the main channel of the eccentric body within the iron column. In the eccentric water distributor of this utility model, the through hole of the upper connector, the through hole of the straightening body, the main channel of the eccentric body, and the through hole of the lower connector are on the same axis; the lower connecting section of the upper connector, the connecting sleeve, the outer wall of the iron column, the outer wall of the eccentric body, the axial positioning sleeve, and the upper connecting section of the lower connector are coaxial.

[0018] like Figure 2 , Figure 3As shown, a release guide slot 5 for the retrieval tool is opened on the thick-walled side of the eccentric tube, corresponding to the position of the plug installation hole. The release guide slot cuts the eccentric tube into an open eccentric tube with a C-shaped cross-section. A stainless steel inner lining is provided on the inner wall of the tube hole of the open eccentric tube. A conical guide port 2, coaxial with the iron column, is provided at the upper end of the open eccentric tube. Since the iron column and the tube hole are not on the same axis, a guide cone surface with an arc-shaped boundary is formed at the upper end of the open eccentric tube, which is more conducive to the guide claw entering the release guide slot of the retrieval tool.

[0019] like Figure 1 , Figure 2 As shown, at the lower end of the release guide straight groove of the stabilizing body, there is a guide claw retraction rail 6 that causes the guide claw of the stabilizing body to retract inward. The guide claw retraction rail protrudes from the wall surface of the release guide straight groove of the stabilizing body, and the angle between the rail surface of the guide claw retraction rail and the axis of the inner wall of the pipe hole is 18 degrees.

[0020] Preferably, the stainless steel inner lining is a stainless steel liner 15 that corresponds to the shape of the inner wall of the eccentric tube hole, and the stainless steel liner is welded and fixed to the eccentric tube.

[0021] like Figure 3 As shown, preferably, multiple welding holes 23 are drilled along the radial direction of the pipe hole on the eccentric tube body. The diameter of the welding holes is 5-10 mm, preferably large enough to allow the welding rod to be inserted and welded. The stainless steel liner is welded to the eccentric tube body at the bottom of the welding holes. A non-metallic insulating layer 22 is filled between the stainless steel liner and the eccentric tube body, and sealant 21 is filled into the welding holes. This effectively prevents water from entering between the stainless steel liner and the eccentric tube body made of ordinary steel, thus preventing bimetallic corrosion. This allows the eccentric water distributor of this invention to work for a long time without corrosion, with a service life of more than 6 years.

[0022] Preferably, the thickness of the stainless steel liner is not less than 1 mm.

[0023] In the use of this eccentric water distributor, the eccentric water distributor is lowered to the designated position on the casing according to the water injection requirements. When the blocker is deployed, the blocker is installed on the blocker retrieval claw of the blocker retrieval tool. The blocker retrieval tool is then lowered into the eccentric water distributor along the water injection pipe. After the blocker retrieval tool enters the eccentric water distributor, the guide claw located on the lower side wall of the blocker retrieval tool pops out. Guided by the slope of the tapered guide pipe at the upper end of the open eccentric pipe body, it automatically adjusts its angle and enters the release guide straight groove of the retrieval tool. The blocker retrieval tool continues to descend under the guidance of the guide claw, and the blocker retrieval claw enters from the upper end of the release guide straight groove of the retrieval tool. The blocker removal tool continues to descend as it enters the centering body and springs back. As the guide claw passes the guide claw retracting rail at the lower end of the centering body, it retracts inward under the guidance of the guide claw retracting rail, embedding the blocker removal tool and entering the main channel of the eccentric body. After passing through the main channel of the eccentric body, the guide claw springs back out. Guided by the circumferential guide body, it automatically and precisely adjusts the angle of the blocker removal claw, aligning the lower end of the blocker with the blocker mounting hole on the eccentric body. At this point, the blocker removal tool continues to descend, inserting and locking the blocker into the mounting hole. The blocker removal tool is then lifted, leaving the blocker in the eccentric water distributor, completing the blocker removal operation. During the plug retrieval process, the plug retrieval tool without the plug installed is lowered from the water injection pipe to the eccentric water injector. The working process of the plug retrieval tool guide claw and the retrieval claw is similar to the plug deployment process. The retrieval claw is aligned with the upper end of the plug, so that the retrieval head at the upper end of the plug is inserted into the retrieval claw and locked. The plug retrieval tool is then lifted up, and the plug is brought to the surface, completing the plug retrieval operation.

Claims

1. An eccentric water distributor, comprising an eccentric upper connector, an eccentric lower connector, and a connecting sleeve whose two ends are respectively threaded to the eccentric upper and lower connectors and the eccentric lower connector, wherein a centering body, an eccentric main body, and an axial positioning sleeve are sequentially installed from top to bottom inside the connecting sleeve; a circumferential guide body is installed inside the lower connector; a main channel and a plug mounting hole are provided on the eccentric main body; a water distribution hole is provided on the wall of the plug mounting hole; a sealing device that slides and seals with the connecting sleeve is provided on the outer wall of the eccentric main body on the upper and lower sides of the water distribution hole; and a water injection hole is provided on the connecting sleeve at the position corresponding to the water distribution hole, characterized in that: The straightening body is an eccentric tube consisting of an iron column coaxial with the outer wall of the eccentric main body and a pipe hole coaxial with the main channel of the eccentric main body inside the iron column. A straight groove for releasing the retrieval tool is opened on the thick wall side of the eccentric tube, corresponding to the position of the blocker installation hole. The straight groove for releasing the retrieval tool cuts the eccentric tube into an open eccentric tube with a C-shaped cross section. A stainless steel inner lining layer is provided on the inner wall of the pipe hole of the open eccentric tube. A tapered guide pipe opening coaxial with the iron column is provided at the upper end of the open eccentric tube.

2. The eccentric water distributor according to claim 1, characterized in that: The stainless steel inner lining is a stainless steel liner that corresponds to the shape of the inner wall of the eccentric tube body, and the stainless steel liner is welded onto the eccentric tube body.

3. The eccentric water distributor according to claim 2, characterized in that: Multiple welding holes are drilled along the radius of the pipe hole on the eccentric tube body. The stainless steel liner is welded and fixed to the eccentric tube body at the bottom of the welding hole. A non-metallic insulating layer is filled between the stainless steel liner and the eccentric tube body, and sealant is filled in the welding hole.

4. The eccentric water distributor according to claim 3, characterized in that: The thickness of the stainless steel inner lining is not less than 1 mm.

5. The eccentric water distributor according to any one of claims 1 to 4, characterized in that: The outer wall at the lower end of the positioning sleeve is provided with an axial position adjustment thread that mates with the threaded inner wall of the connecting sleeve.

6. The eccentric water distributor according to claim 5, characterized in that: A fixing screw hole is provided on the circumferential guide body, and a positioning screw hole for the circumferential guide body is provided on the lower connector. A guide body fixing screw is installed in the positioning screw hole of the guide body.

7. The eccentric water distributor according to claim 6, characterized in that: At the lower end of the release guide straight groove of the stabilizing body, there is a guide claw retraction guide rail that retracts the guide claw of the stabilizing body. The guide claw retraction guide rail protrudes from the wall surface of the release guide straight groove of the stabilizing body, and the angle between the rail surface of the guide claw retraction guide rail and the axis of the inner wall of the pipe hole is 18 degrees.

8. The eccentric water distributor according to claim 4, characterized in that: An eccentric main body fixing screw is provided on the connecting sleeve.

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