A production process and shaping device of a continuous sucker rod of carbon fiber and metal composite

Abstract

The present application belongs to the technical field of sucker rod, and relates to a production process and a shaping device of a continuous sucker rod composed of carbon fiber and metal. The production process comprises the following key steps in sequence: raw material preparation, preparation of composite fiber single strand, core preparation, resin impregnation, coating and solidification of filling layer, shaping and coating of metal protective sleeve, multi-directional rolling and dynamic double shaping cooperation, etc. The shaping device is composed of a multi-directional rolling mechanism and a seam shaping mechanism, which can precisely control the seam alignment accuracy during the rolling process while performing multi-directional rolling on the metal belt. The process and device can produce a continuous sucker rod with light weight, high strength, high temperature and pressure resistance, and excellent corrosion resistance, effectively solving the technical bottleneck of low tensile strength and poor corrosion resistance of traditional carbon fiber sucker rod, and meeting the use requirements of high temperature and pressure complex downhole working conditions.

Description

Technical Field

[0001] This invention relates to the field of mechanical oil extraction technology using oil rod pumps, and in particular to a production process and shaping device for a continuous sucker rod made of carbon fiber and metal composite. Background Technology

[0002] As oil extraction operations continue to extend into deeper oil layers, ultra-deep wells, directional wells, and complex well conditions such as high-sulfur, high-salinity reservoirs and high-temperature, high-pressure environments, the operating depth of oil pumps is also constantly increasing.

[0003] To adapt to these deep well operation conditions, the industry has developed lightweight, high-strength, and highly corrosion-resistant composite sucker rod structures. These structures generally employ a design where a metal jacket encases a lightweight fiber core. However, key technical bottlenecks still exist in practical applications, with the following being particularly prominent:

[0004] After the metal jacket is rolled, poor joint alignment is prone to occur, which makes it difficult to accurately control the joint alignment of its axial weld. This directly affects the welding quality and overall product reliability. Furthermore, the existing processing technology lacks a specific weld shaping procedure, which cannot effectively control the joint alignment, further reducing product reliability and making it difficult to meet the operational needs of complex well conditions.

[0005] Therefore, in order to address the shortcomings of existing technologies, it is essential to provide a manufacturing process and shaping device for continuous sucker rods made of carbon fiber and metal composites. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a production process and shaping device for a continuous sucker rod made of carbon fiber and metal composite. This continuous sucker rod adopts a layered composite structure of carbon fiber filaments and various reinforcing fiber filaments, with polyurethane resin as the impregnation and filling material. The shaping device is a specialized piece of equipment that can perform multi-directional rolling on the metal strip and precisely control the seam alignment accuracy during the rolling process. By using the production process and shaping device of this invention in combination, the weld formation quality after rolling the metal strip can be greatly improved, effectively avoiding gaps in the weld. This can greatly improve the problem of poor weld effect caused by misalignment of the metal outer casing in traditional composite sucker rods.

[0007] The above-mentioned objectives of the present invention are achieved by the following technical means.

[0008] A manufacturing process and shaping apparatus for a continuous sucker rod composed of carbon fiber and metal is provided, comprising the following steps:

[0009] S1: Raw Material Preparation

[0010] The raw materials include carbon fiber filaments, reinforcing fiber filaments, resin liquid and metal strips. Among them, the carbon fiber filaments are made of high-strength, high-modulus carbon fiber, which can provide excellent tensile strength for sucker rods.

[0011] The reinforcing fiber is one or more of aramid fiber, glass fiber, basalt fiber and alumina fiber. The appropriate type of reinforcing fiber can be selected according to different working conditions to further improve the overall performance of the sucker rod.

[0012] The resin adhesive is made of polyurethane resin, which has good adhesion, corrosion resistance and temperature resistance, and can ensure a tight bond between the fiber core and the filling layer and the metal protective jacket.

[0013] The metal strip can be made of different types of stainless steel such as 304 and 316, and the thickness is selected according to actual needs, usually ≤0.6mm, to ensure the protective performance and lightweight requirements of the metal protective jacket.

[0014] S2: Preparation of composite fiber single strand yarn

[0015] Multiple carbon fiber filaments and multiple reinforcing fiber filaments are selected and twisted together using a twisting machine to produce composite fiber single strands with a diameter of 3-6mm.

[0016] The composite fiber single strand yarn adopts a core-sheath composite structure design. The core layer is made of multiple carbon fiber filaments, and the outer layer is covered with reinforcing fiber filaments. The reinforcing fiber filaments are one or more of aramid fiber, glass fiber, basalt fiber, and alumina fiber. The structure and mechanical properties of the single strand yarn are optimized through the complementary material properties of the core layer and the outer layer.

[0017] Multiple carbon fiber filaments are twisted together by a stranding machine to form an inner layer fiber filament. The outer layer of the inner layer fiber filament, which serves as the core layer, is then twisted together by a stranding machine to wrap multiple reinforcing fiber filaments, thus producing the composite fiber single strand.

[0018] S3: Core Preparation

[0019] Composite fiber cores can be formed directly from a single large-diameter composite fiber strand, or they can be formed by stranding multiple small-diameter composite fiber strands together using a stranding machine. Composite fiber cores made from single composite fiber strands have a compact structure, high hardness, and are durable.

[0020] The composite fiber core structure, formed by twisting multiple strands of composite fiber into a uniform shape, has good bending performance and is easy to wind onto small-diameter reels, making it convenient for roll storage and transportation. At the same time, it effectively avoids stress concentration under stress, significantly improving tensile strength and structural stability.

[0021] S4: Impregnating resin solution

[0022] The composite fiber core is fully impregnated with polyurethane resin to obtain a polymer-fiber composite core. Through impregnation, the polyurethane resin can fully penetrate into the interior of the composite fiber core, fill the gaps between the fibers, improve the integrity and bonding strength of the core, and lay a good foundation for subsequent filling layer coating. The impregnation time can be adjusted according to the size of the core and the type of fiber to ensure that the fiber core is completely wetted.

[0023] S5: Filler layer coating and curing

[0024] The polyurethane resin is forcefully extruded into the fiber gaps of the polymer-fiber composite core under high pressure using an extruder to form a filling layer, and then cured in a tunnel curing oven to obtain the coated core.

[0025] The filling layer can further fill the tiny gaps on the surface of the composite fiber core, making the surface of the core smoother. The curing treatment of the filling layer can fully cross-link and cure the polyurethane resin, further improving the structural strength, corrosion resistance and temperature resistance of the continuous sucker rod, and ensuring the stable operation of the sucker rod under complex working conditions.

[0026] S6: Metal protective jacket covering

[0027] The metal strip to be rolled and the core to be covered are simultaneously fed into the multi-directional rolling mechanism of the forming device, and the horizontal, vertical and oblique multi-directional rolling operations are completed in sequence. The rolling diameter is reduced at equal intervals along the rolling direction, so that the metal strip is tightly attached to the outer surface of the core. During the rolling process, multiple sets of cross rolling components with progressively connected rolling diameters roll the metal strip to form a curved surface structure with equal-distance narrowing of the diameter.

[0028] The truss robot controls the top pressing and shaping plate, which moves back and forth within the rolling stroke of each level of cross roller pressing assembly. This achieves dynamic double shaping of the cylindrical gap area of ​​the metal strip after rolling, so that the metal strip is rolled to form a metal protective jacket with flat and aligned weld edges.

[0029] S7: Welded seam

[0030] The seams of the metal protective jacket are marked as weld seams, and the weld seams are butt-welded using argon arc welding to form a composite sucker rod blank.

[0031] The shaping device ensures a tight fit between the metal protective jacket and the core, while precisely controlling the alignment accuracy of the seams during the metal strip winding process. This significantly improves the weld formation quality of the metal protective jacket and effectively prevents gaps from forming in the weld.

[0032] S8: Heat treatment of weld seam

[0033] The welded composite sucker rod blank is sent into an induction heating furnace for continuous induction heat treatment of the weld. The weld is then tempered to eliminate welding stress, refine the weld grains, improve the microstructure, and enhance the plasticity and impact toughness of the weld, thus producing a continuous sucker rod composed of carbon fiber and metal. Meanwhile, the workpiece traction operations in processes S6 to S8 are all achieved using an automatic metal tube drawing and traction machine.

[0034] S9: Finished Product Inspection

[0035] The continuous sucker rod undergoes visual inspection, dimensional accuracy testing, tensile strength testing, and corrosion resistance testing. After passing the tests, it is cut to the set length according to the usage requirements and wound onto a special tray to obtain the finished sucker rod body.

[0036] Visual inspection mainly checks for cracks, scratches, weld defects, and other problems on the surface of the sucker rod. Dimensional accuracy testing ensures that the diameter, length, and other dimensions of the sucker rod meet the design requirements. Tensile strength testing and corrosion resistance testing verify whether the tensile strength and corrosion resistance of the sucker rod meet the usage requirements, respectively. Through a rigorous inspection process, the reliability of the finished product is guaranteed.

[0037] The shaping device is installed on the rolling path of the metal strip in the above production process. It controls the seam alignment accuracy of the metal strip during the rolling process through multi-directional rolling to form a qualified metal protective jacket. The shaping device includes a multi-directional rolling mechanism and several seam shaping mechanisms.

[0038] The automatic metal tube drawing traction machine is used to pull the composite sucker rod blank, providing traction power for the rolling and shaping of the metal strip, ensuring that the metal strip can smoothly and continuously enter the subsequent processing steps.

[0039] During the process of being pulled by the automatic metal tube drawing and traction machine, the metal strip is rolled into a tubular shape by the multi-directional rolling mechanism. After being rolled in multiple directions, the outside of the metal strip is tightly attached to the outside of the core body. At the same time, the cylindrical gaps formed by the multi-directional rolling mechanism are reduced in equal intervals.

[0040] The multi-directional rolling mechanism includes multiple sets of progressively distributed cross rolling components and a set of inclined rolling components at the end of the rolling stroke. The rolling diameter values ​​of the multiple sets of cross rolling components vary at equal intervals along the horizontal direction, which can realize progressive rolling and shaping of the metal strip, so that the metal strip and the covering core are closely bonded.

[0041] The fixed roller and the moving roller of the cross roller pressing assembly are vertically abutted against both sides of the metal strip. The two ends of the fixed roller are mounted on the vertical support frame through bearings, and the two ends of the moving roller are mounted on the lead screw nut through bearings. The lead screw nut is connected to the ball screw drive. One end of the ball screw is equipped with a servo motor A, and the ball screw is installed inside the vertical support frame.

[0042] Servo motor A drives the ball screw to rotate, which in turn moves the screw nut and the moving roller in the vertical direction, thereby adjusting the distance between the fixed roller and the moving roller. Finally, the metal strip passing through the feed end of the cross roller pressing assembly is subjected to roller pressing and shaping.

[0043] A set of bidirectional ball screw slides is installed on one side of the vertical support frame. A set of rollers is installed on the bidirectional ball screw slides. The rollers are horizontally abutted against both sides of the metal strip. The bidirectional ball screw slides can drive the two single rollers to move relative to each other in the horizontal direction, further adjusting the roller diameter of the rollers on the metal strip, and ensuring that the metal strip can be evenly and tightly attached to the outside of the core.

[0044] The inclined roll forming assembly includes a hollow frame, which is installed on one side of the cross roll forming assembly. A servo motor C is installed on the hollow frame, and the output end of the servo motor C is connected to a worm gear. While driving the worm gear to rotate, it also drives the hollow worm wheel installed on the hollow frame to rotate. A pair of swing rollers are installed radially on the hollow worm wheel, and the swing rollers are in movable contact with the outer side of the metal strip.

[0045] The worm gear driven by the servo motor C drives the hollow worm wheel to rotate, and the rotation angle of the swing roller is synchronously controlled. After the metal strip is initially processed by bidirectional rolling of the cross roller pressing assembly, it is then refined by the swing roller with oblique rolling, which effectively improves the neatness and tightness of the steel strip joint.

[0046] The seam shaping mechanism includes multiple truss robots that move horizontally and reciprocally above the metal strip during rolling. Each truss robot is equipped with a shaping adjustment component at its telescopic end. The shaping adjustment component can perform dynamic double shaping according to the size of the cylindrical gap in the metal protective jacket, ensuring a smooth and aligned weld edge.

[0047] The hollow platform of the shaping and adjustment component is installed at the telescopic end of the gantry robot. Inside the hollow platform, two rotating shafts are movably installed via bearings. The gears at the same side ends of the two rotating shafts are installed in a staggered manner and mesh with the racks arranged above and below. One end of each rack is connected to a servo electric push rod, and the other end of the rack is slidably engaged in a sliding engagement groove opened on the hollow platform.

[0048] Angle adjustment rods mounted on the two rotating shafts are arranged in an X-shape. A servo motor B is installed at the bottom of each angle adjustment rod. A top pressure shaping plate is fixedly mounted on the output shaft of the servo motor B. The two top pressure shaping plates are arranged in a front-to-back cross-symmetrical layout and are snapped into the cylindrical seam formed by the metal protective jacket and the core. Through this structure, the internal support and external pressure shaping action of the cylindrical seam of the metal protective jacket is realized, and the shaping and fine shaping docking of the seam of the metal protective jacket is completed.

[0049] The servo system completes the initialization settings based on the design parameters of the composite sucker rod, matches the decreasing gradient of the roller diameter of the cross roller pressing assembly, presets the rack sliding stroke of the servo electric push rod, sets the speed synchronization ratio of servo motor A according to the feeding speed, presets the initial angle of servo motor B driving the top pressing and shaping plate according to the curvature of the covering core, and sets the motion parameters of the gantry robot.

[0050] After receiving the shaping signal, the automatic metal tube pulling traction machine pulls the covering core and metal strip to feed synchronously. Servo motor A drives the cross roller pressing assembly for multi-stage rolling. The gantry robot moves the shaping and adjustment assembly. The servo electric push rod and servo motor B start with a delay to avoid interference. During rolling, the servo system adjusts the spacing of the top pressing shaping plate through the servo electric push rod and corrects the angle through servo motor B, based on sensor feedback. The double shaping is completed by the combination of internal support and external pressure.

[0051] The roller diameter of the multiple cross roller pressing components changes gradually from large to small. This design enables the gradual shaping of the metal strip, avoiding defects such as cracks and wrinkles caused by excessive deformation during one-time rolling, and improving the forming quality of the metal protective jacket.

[0052] The continuous sucker rod of the present invention, which is a carbon fiber and metal composite, adopts a layered composite structure of carbon fiber filaments and various reinforcing fiber filaments, and uses polyurethane resin as an impregnation and filling material, which significantly improves the tensile strength and corrosion resistance of the sucker rod. In addition, the forming device controls the seam alignment accuracy of the metal strip during the rolling process while rolling the metal strip in multiple directions. Attached Figure Description

[0053] The invention will be further described with reference to the accompanying drawings, but the contents of the drawings do not constitute any limitation on the invention.

[0054] Figure 1 This is a process flow diagram of a continuous sucker rod made of carbon fiber and metal composite according to the present invention.

[0055] Figure 2 This is a cross-sectional view of the composite fiber core structure of a continuous sucker rod made of carbon fiber and metal according to the present invention.

[0056] Figure 3 This is a structural diagram of the composite fiber core of a single composite fiber strand of a continuous sucker rod made of carbon fiber and metal according to the present invention.

[0057] Figure 4 This is a structural diagram of the composite fiber core obtained by twisting seven strands of composite fiber single strands together in a continuous sucker rod of carbon fiber and metal according to the present invention.

[0058] Figure 5This is a structural diagram of a composite fiber core obtained by twisting 19 strands of composite fiber single strands together in a continuous sucker rod of carbon fiber and metal according to the present invention.

[0059] Figure 6 This is a structural diagram of a composite fiber core obtained by twisting 37 strands of composite fiber single strands together in a continuous sucker rod of carbon fiber and metal according to the present invention.

[0060] Figure 7 This is a schematic diagram of the composite fiber single strand structure of a continuous sucker rod made of carbon fiber and metal according to the present invention.

[0061] Figure 8 This is a perspective view of the overall structure of a shaping device for a continuous sucker rod made of carbon fiber and metal composite according to the present invention.

[0062] Figure 9 This is a partial three-dimensional view of a shaping device for a continuous sucker rod made of carbon fiber and metal composite according to the present invention.

[0063] Figure 10 This is a partial three-dimensional view of a shaping device for a continuous sucker rod made of carbon fiber and metal composite according to the present invention.

[0064] Figure 11 This is an enlarged view of the suture shaping mechanism A of the shaping device for a continuous sucker rod made of carbon fiber and metal composite according to the present invention.

[0065] from Figures 1 to 11 Including:

[0066] 1. Core coating;

[0067] 2. Metal protective jacket;

[0068] 3. Shaping device;

[0069] 4. Steel strip feeder;

[0070] 5. Multi-directional roller pressing mechanism;

[0071] 6. Suture shaping mechanism;

[0072] 7. Composite fiber single strand yarn;

[0073] 71. Carbon fiber filament; 72. Reinforcing fiber filament;

[0074] 8. Composite fiber core;

[0075] 9. Shaping and adjustment components;

[0076] 10. Hollow platform;

[0077] 11. Rotating shaft;

[0078] 12. Gear;

[0079] 13. Gear rack;

[0080] 14. Servo electric linear actuator;

[0081] 15. Sliding card slot;

[0082] 16. Angle adjustment lever;

[0083] 17. Top-pressure shaping plate;

[0084] 18. Cross roll forming assembly;

[0085] 19. Inclined roller pressing assembly;

[0086] 20. Fixed roller;

[0087] 21. Moving roller;

[0088] 22. Lead screw nut;

[0089] 23. Ball screw;

[0090] 24. Two-way ball screw slide;

[0091] 25. Roller pressing wheel;

[0092] 26. Worm gear;

[0093] 27. Hollow worm gear;

[0094] 28. Swinging roller;

[0095] 29. Automatic winding machine;

[0096] 30. Guiding elements;

[0097] 31. Resin adhesive. Detailed Implementation

[0098] The present invention will be further described in conjunction with the following embodiments.

[0099] Example 1.

[0100] A manufacturing process for a continuous sucker rod composed of carbon fiber and metal includes the following steps:

[0101] S1: Raw material preparation, including carbon fiber filament 71, reinforcing fiber filament 72, glass fiber, polyurethane resin and metal strip, wherein the metal strip is 304 stainless steel strip with a thickness of 0.5mm.

[0102] S2: Preparation of composite fiber monofilament 7: 23 carbon fiber filaments 71 are used as the core layer and 47 glass fibers are used as the outer layer. The composite fiber monofilament 7 with a diameter of 28mm is obtained by twisting and combining them through a twisting machine.

[0103] S3: Core preparation, to obtain a composite fiber core 8 using a single strand of composite fiber 7.

[0104] S4: Impregnate with resin solution 31, fully impregnate the composite fiber core 8 with the polymer material polyurethane resin for 10 minutes to ensure that the fiber core is completely wetted, and obtain the polymer-fiber composite core.

[0105] S5: The filler layer is coated and cured. Polyurethane resin is forcefully extruded into the fiber gaps of the polymer-fiber composite core under high pressure by an extruder to form a filler layer. Then, it is cured at 130°C by a tunnel curing oven to obtain the coated core 1, which is composed of the filler layer and the composite fiber core 8.

[0106] S6: The metal protective jacket 2 covers the metal strip to be rolled and the core 1 is simultaneously fed into the multi-directional rolling mechanism 5 of the forming device 3. The horizontal, vertical and oblique multi-directional rolling operations are completed in sequence. The rolling diameter is reduced at equal intervals along the rolling direction, so that the metal strip is tightly attached to the outer surface of the core 1. During the rolling process, multiple sets of cross rolling components 18 connected by the rolling diameter step by step roll the metal strip to form a curved surface structure with equal-distance narrowing of the diameter.

[0107] The truss robot controls the top pressing and shaping plate 17 to reciprocate within the rolling stroke of the cross roller pressing assembly 18 at each level, realizing dynamic double shaping of the cylindrical gap part of the metal strip after rolling, so that the metal strip is rolled to form a metal protective jacket 2 with flat and aligned weld edges.

[0108] S7: Welded seam

[0109] The seams of the metal protective jacket 2 are marked as weld seams, and the weld seams are butt welded using argon arc welding to form a composite sucker rod blank.

[0110] The shaping device 3 ensures a tight fit between the metal protective jacket 2 and the covering core 1, while precisely controlling the alignment accuracy of the seams during the metal strip winding process. This significantly improves the weld formation quality of the metal protective jacket 2 and effectively prevents gaps from forming in the weld.

[0111] S8: Weld heat treatment. The welded composite sucker rod blank is sent into an induction heating furnace for continuous induction heat treatment of the weld. The internal stress of the weld is eliminated by tempering, the weld grains are refined, the microstructure is improved, and the plasticity and impact toughness of the weld are improved, so as to obtain a continuous sucker rod of carbon fiber and metal composite. At the same time, the workpiece traction operation in S6 to S8 is realized by an automatic metal tube drawing traction machine.

[0112] S9: Finished product inspection. Visual inspection of the continuous sucker rod is conducted to check for cracks, scratches, weld defects, etc. Dimensional accuracy is checked to ensure that the diameter, length, and other dimensions meet the design requirements. Tensile strength and corrosion resistance tests are performed. After passing the tests, the rod is cut to the set length according to the usage requirements and wound onto a special tray to obtain a finished sucker rod body with a diameter of 30mm. The diameter tolerance of the finished sucker rod body must be strictly controlled within 0.05mm to ensure product quality and meet high-precision usage requirements.

[0113] The shaping device 3 is installed on the rolling path of the metal strip in the above production process. It controls the seam alignment accuracy during the rolling process of the metal strip through multi-directional rolling to form a qualified metal protective jacket 2. The shaping device 3 includes a multi-directional rolling mechanism 5 and several seam shaping mechanisms 6.

[0114] The automatic metal tube drawing traction machine is used to pull the composite sucker rod blank, providing traction power for the rolling and shaping of the metal strip, ensuring that the metal strip can smoothly and continuously enter the subsequent processing steps.

[0115] During the process of being pulled by the metal tube automatic drawing and traction machine, the metal strip is rolled into a tubular shape by the multi-directional rolling mechanism 5. After being rolled by the multi-directional rolling mechanism, the outside of the metal strip is tightly attached to the outside of the covering core 1. At the same time, the gaps between the cylindrical surfaces formed by the multi-directional rolling mechanism 5 are reduced in equal intervals.

[0116] The multi-directional rolling mechanism 5 includes multiple sets of progressively distributed cross rolling components 18 and a set of inclined rolling components 19 at the end of the rolling stroke. The rolling diameter values ​​of the multiple sets of cross rolling components 18 vary at equal intervals along the horizontal direction, which can realize progressive rolling and shaping of the metal strip, so that the metal strip and the covering core 1 are closely attached.

[0117] The fixed roller 20 and the moving roller 21 of the cross roller pressing assembly 18 are vertically abutted against both sides of the metal strip. The two ends of the fixed roller 20 are mounted on the vertical support frame through bearings, and the two ends of the moving roller 21 are mounted on the lead screw nut 22 through bearings. The lead screw nut 22 is connected to the ball screw 23 for transmission. One end of the ball screw 23 is equipped with a servo motor A, and the ball screw 23 is installed inside the vertical support frame.

[0118] Servo motor A drives ball screw 23 to rotate, which in turn drives screw nut 22 and moving roller 21 to move in the vertical direction, thereby adjusting the distance between fixed roller 20 and moving roller 21, and finally performing roll forming operation on the metal strip that passes through the feed end of the cross roll forming assembly 18.

[0119] A set of bidirectional ball screw slides 24 is installed on one side of the vertical support frame. A set of rollers 25 are installed on the bidirectional ball screw slides 24. The rollers 25 are horizontally abutting against both sides of the metal strip. The bidirectional ball screw slides 24 can drive the two single rollers 25 to move relative to each other in the horizontal direction, further adjusting the roller diameter of the rollers 25 on the metal strip, and ensuring that the metal strip can be evenly and tightly attached to the outside of the core 1.

[0120] The inclined roller pressing assembly 19 includes a hollow upright frame, which is installed on one side of the cross roller pressing assembly 18. A servo motor C is installed on the hollow upright frame, and the output end of the servo motor C is connected to the worm gear 26. While driving the worm gear 26 to rotate, it also drives the hollow worm wheel 27 installed on the hollow upright frame to rotate. A pair of swing rollers 28 are installed radially on the hollow worm wheel 27, and the swing rollers 28 are in movable contact with the outer side of the metal strip.

[0121] The worm gear 26 driven by the servo motor C drives the hollow worm wheel 27 to rotate, and the rotation angle of the swing roller 28 is adjusted synchronously. After the metal strip is initially processed by bidirectional rolling of the cross roller assembly 18, it is then finely rolled by the swing roller 28 with oblique rolling, which effectively improves the neatness and tightness of the steel strip joint.

[0122] The seam shaping mechanism 6 includes multiple truss robots that move horizontally and reciprocally above the metal strip during rolling. Each truss robot is equipped with a shaping adjustment component 9 at its telescopic end. The shaping adjustment component 9 can perform dynamic double shaping according to the size of the cylindrical gap in the metal protective jacket 2 to ensure a smooth and aligned weld edge.

[0123] The hollow platform 10 of the shaping and adjusting assembly 9 is installed on the telescopic end of the gantry manipulator. Inside the hollow platform 10, two rotating shafts 11 are movably installed through bearings. The gears 12 on the same side of the two rotating shafts 11 are installed in a staggered manner and mesh with the racks 13 arranged above and below. One end of the two racks 13 is connected to the servo electric push rod 14, and the other end of the racks 13 is slidably engaged in the sliding engagement groove 15 opened on the hollow platform 10.

[0124] Angle adjustment rods 16 mounted on the two rotating shafts 11 are arranged in an X-shape. A servo motor B is installed at the bottom of each angle adjustment rod 16. A top pressure shaping plate 17 is fixedly mounted on the output shaft of the servo motor B. The two top pressure shaping plates 17 are arranged in a front-to-back cross symmetrical layout and are snapped into the cylindrical seam formed by the metal protective jacket 2 and the core 1. Through this structural adaptation, the internal support and external pressure shaping action at the cylindrical seam of the metal protective jacket 2 is realized, and the shaping and fine shaping docking of the seam part of the metal protective jacket 2 is completed.

[0125] The servo system completes the initialization settings based on the design parameters of the composite sucker rod, matches the decreasing gradient of the roller diameter of the cross roller pressing assembly 18, presets the sliding stroke of the rack 13 of the servo electric push rod 14, sets the speed synchronization ratio of the servo motor A according to the feeding speed, presets the initial angle of the servo motor B driving the top pressing shaping plate 17 according to the curvature of the covering core 1, and sets the motion parameters of the gantry robot.

[0126] After receiving the shaping signal, the automatic metal tube pulling traction machine pulls the core 1 and the metal strip to feed synchronously. Servo motor A drives the cross roller pressing assembly 18 to perform multi-stage rolling. The gantry robot moves the shaping adjustment assembly 9. The servo electric push rod 14 and servo motor B start with a delay to avoid interference. During rolling, the servo system adjusts the spacing of the top pressing shaping plate 17 through the servo electric push rod 14 and corrects the angle through the servo motor B, based on sensor feedback. The double shaping is completed by the combination of internal support and external pressure.

[0127] The roller diameter of the multiple cross roller pressing components 18 changes gradually from large to small. This design can achieve step-by-step shaping of the metal strip and avoid defects such as cracks and wrinkles in the metal strip due to excessive deformation during one-time roller pressing, thereby improving the forming quality of the metal protective jacket 2.

[0128] The shaping device 3 can simultaneously roll the metal strip in multiple directions and control the seam alignment accuracy during the metal strip winding process.

[0129] The composite continuous sucker rod prepared in this embodiment underwent a full range of performance tests. The test results showed that by twisting 23 carbon fiber filaments 71 as the core layer and 47 glass fibers as the outer layer using a twisting machine, a composite fiber single strand 7 with a diameter of 28 mm was obtained. The outer layer was covered with a 0.5 mm thick 304 stainless steel strip, and a finished sucker rod body with a diameter of 30 mm was made.

[0130] The composite continuous sucker rod prepared in this embodiment was subjected to performance testing, and the results are as follows: the tensile strength is about 1900 MPa, the Vickers hardness HV is about 390, which shows good hardness and can withstand the tensile strength requirements of ultra-deep wells. The metal protective jacket 2 is tightly fitted to the encased core 1, the weld seam is flawless, the surface of the continuous sucker rod is smooth, reducing frictional damage between the continuous sucker rod and the well wall, and it has excellent corrosion resistance.

[0131] After being immersed in crude oil for 1000 hours under high temperature and high pressure conditions of 150℃ and 20MPa, the tensile strength retention rate of the sucker rod is ≥83%, which is significantly better than that of ordinary sucker rods.

[0132] The metal protective jacket 2 fits tightly with the core 1, the weld seam is shaped without obvious defects, the surface of the continuous sucker rod is smooth, the friction coefficient with the well wall is reduced by 35%, the corrosion resistance is good, and the service life is increased by more than 30% compared with traditional products. It can effectively reduce the maintenance cost of oilfield production operations and significantly reduce equipment downtime.

[0133] Example 2.

[0134] This embodiment has the same structure as Embodiment 1 for the shaping device 3, but the difference lies in the manufacturing process of a continuous sucker rod made of carbon fiber and metal composite:

[0135] S1: Raw material preparation, including carbon fiber filament 71, reinforcing fiber filament 72, glass fiber, polyurethane resin and metal strip, wherein the metal strip is 304 stainless steel strip with a thickness of 0.5mm.

[0136] S2: Preparation of composite fiber monofilament 7: 7 carbon fiber filaments 71 are used as the core layer and 14 glass fibers are used as the outer layer. The composite fiber monofilament 7 with a diameter of 5.5 mm is obtained by twisting and combining them through a twisting machine.

[0137] S3: Core preparation: According to the designed number of strands, the 7 strands of composite fiber single strands 7 are twisted together by a stranding machine to obtain the composite fiber core 8.

[0138] S4: Impregnate with resin solution 31, fully impregnate the composite fiber core 8 with the polymer material polyurethane resin for 10 minutes to ensure that the fiber core is completely wetted, and obtain the polymer-fiber composite core.

[0139] S5: The filling layer is coated and cured. Polyurethane resin is forcefully extruded into the gaps between the 7 strands of composite fiber single strands 7 of the polymer-fiber composite core under high pressure by an extruder to form a filling layer. Then, it is cured at 130°C by a tunnel curing oven to obtain the coated core 1 formed by the combination of the filling layer and the composite fiber core 8.

[0140] S9: Finished product inspection. Visual inspection of the continuous sucker rod is conducted to check for cracks, scratches, weld defects, etc. Dimensional accuracy is checked to ensure that the diameter, length, and other dimensions meet the design requirements. Tensile strength and corrosion resistance tests are performed. After passing the tests, the rod is cut to the set length according to the usage requirements and wound onto a special tray to obtain a finished sucker rod body with a diameter of 22mm. The diameter tolerance of the finished sucker rod body must be strictly controlled within 0.05mm to ensure product quality and meet high-precision usage requirements.

[0141] The composite continuous sucker rod prepared in this embodiment was subjected to a full range of performance tests. The test results showed that: a composite fiber single strand 7 with a diameter of 5.5 mm was made by twisting 7 carbon fiber filaments 71 as the core layer and 14 glass fibers as the outer layer. The 7 strands of the single strand were then twisted together and covered with a 0.5 mm thick 304 stainless steel strip to make a finished sucker rod body with a diameter of 22 mm.

[0142] The continuous sucker rod has a tensile strength of approximately 2500 MPa and a Vickers hardness (HV) of approximately 200. It exhibits good bending resistance and can fully meet the high-load requirements of deep well operations. After being immersed in crude oil for 1000 hours under high temperature and high pressure conditions of 150℃ and 20MPa, the tensile strength retention rate of the sucker rod is ≥92%, which is significantly better than that of ordinary sucker rods.

[0143] Example 3.

[0144] This embodiment has the same structure as Embodiment 1 for the shaping device 3, but the difference lies in the manufacturing process of a continuous sucker rod made of carbon fiber and metal composite:

[0145] S1: Raw material preparation, including carbon fiber filament 71, reinforcing fiber filament 72 (selected from aramid fiber, polyurethane resin, and 0.4mm thick 316 stainless steel strip).

[0146] S2: Preparation of composite fiber monofilament 7: 7 carbon fiber filaments 71 are placed in the core layer and 12 aramid fibers are placed in the outer layer. The composite fibers are twisted together by a twisting machine to obtain a composite fiber monofilament 7 with a diameter of 4.5 mm.

[0147] S3: Core preparation: According to the designed number of strands, 19 strands of composite fiber single strand 7 are stranded together by a stranding machine to obtain composite fiber core 8.

[0148] S4: Impregnate with resin solution 31, fully impregnate the composite fiber core 8 with the high-molecular-weight polyurethane resin for 15 minutes to ensure complete impregnation of the fiber core.

[0149] S5: The filling layer is coated and cured. Polyurethane resin is forcefully extruded into the gaps between the 19 strands of composite fiber single strands 7 of the polymer-fiber composite core under high pressure by an extruder to form a filling layer. Then, it is cured at 125°C by a tunnel curing oven to obtain the coated core 1 formed by the combination of the filling layer and the composite fiber core 8.

[0150] S9: Finished product inspection. Visual inspection of the continuous sucker rod is conducted to check for cracks, scratches, weld defects, etc. Dimensional accuracy is checked to ensure that the diameter, length, and other dimensions meet the design requirements. Tensile strength and corrosion resistance tests are performed. After passing the tests, the rod is cut to the set length according to the usage requirements and wound onto a special tray to obtain a finished sucker rod body with a diameter of 25mm. The diameter tolerance is strictly controlled within 0.05mm to ensure the stable and reliable product quality of the finished sucker rod body.

[0151] The composite continuous sucker rod prepared in this embodiment was subjected to performance testing, and the results are as follows: the tensile strength is about 2300 MPa, the Vickers hardness HV is about 300, which meets the strength requirements of complex well conditions, the bending performance is high, and it can flexibly adapt to the deformation requirements at well bends. The metal protective jacket 2 and the encased core 1 are tightly fitted, the weld seam is shaped without defects, the surface of the continuous sucker rod is smooth, reducing frictional damage between the continuous sucker rod and the well wall, and it has excellent corrosion resistance.

[0152] A composite fiber single strand 7 with a diameter of 4.5 mm is made by twisting 7 carbon fiber filaments 71 as the core layer and 12 aramid fibers placed on the outer layer. Then, 19 strands of this single strand are twisted together and covered with 0.4 mm thick 316 stainless steel strip to make a continuous sucker rod. It has good corrosion resistance and no rust was found after 720 hours of salt spray test.

[0153] This continuous sucker rod is suitable for harsh oil reservoir environments such as those containing sulfur and high salinity. After being immersed in a high-temperature and high-pressure crude oil environment for 1000 hours, the tensile strength retention rate is ≥89%, which is significantly improved compared with ordinary sucker rods. It effectively extends the service life and achieves a precise balance between bending performance and corrosion resistance. It is especially suitable for oil production operations in complex well conditions such as old oilfield renovation and directional wells.

[0154] Example 4.

[0155] This embodiment has the same structure as Embodiment 1 for the shaping device 3, but the difference lies in the manufacturing process of a continuous sucker rod made of carbon fiber and metal composite:

[0156] S1: Raw material preparation, including carbon fiber filament 71, reinforcing fiber filament 72 (selected from aramid fiber and alumina fiber), polyurethane resin, and metal strip (304 stainless steel strip, 0.6mm thick).

[0157] S2: Preparation of composite fiber monofilament 7: Four carbon fiber filaments 71 are used as the core layer, and four aramid fibers and four alumina fibers are twisted together by a twisting machine and placed in the outer layer to obtain a composite fiber monofilament 7 with a diameter of 3.2 mm.

[0158] S3: Core preparation: According to the designed number of strands, 37 strands of composite fiber single strand 7 are stranded together by a stranding machine to obtain composite fiber core 8.

[0159] S4: Impregnate with resin solution 31, fully impregnate the composite fiber core 8 with the high-molecular-weight polyurethane resin for 20 minutes to ensure that the fiber core is completely wetted.

[0160] S5: The filler layer is coated and cured. Polyurethane resin is forcefully extruded into the gaps between the 37 single strands of composite fiber 7 of the polymer-fiber composite core under high pressure by an extruder to form a filler layer. Then, it is cured at 135°C by a tunnel curing oven to obtain the coated core 1 formed by the combination of the filler layer and the composite fiber core 8.

[0161] S9: Finished product inspection. Visual inspection of the continuous sucker rod is carried out to check for cracks, scratches, weld defects, etc. on the surface. Dimensional accuracy is checked to ensure that the diameter, length and other dimensions meet the design requirements. Tensile strength test and corrosion resistance test are performed. After passing the test, the rod is cut to the set length according to the usage requirements and wound onto a special plate to obtain a finished sucker rod body with a diameter of 29mm. The diameter tolerance is controlled within 0.05mm to ensure processing accuracy.

[0162] The performance of the composite continuous sucker rod prepared in this embodiment was tested, and the results are as follows: the tensile strength is about 2000 MPa, the Vickers hardness HV is about 370, it can withstand the gravity load and reciprocating tensile stress of deep wells, and the high temperature short time curing process at 135℃ is used to improve the resin crosslinking density and adapt to the high temperature resistance of alumina fiber.

[0163] A composite fiber monofilament 7 with a diameter of 3.2 mm is made by twisting four carbon fiber filaments 71 as the core layer, four aramid fibers and four alumina fibers together using a twisting machine. Then, 37 strands of this monofilament are twisted together and covered with a 0.6 mm thick 304 stainless steel strip to make a continuous sucker rod. The metal protective jacket 2 is tightly fitted to the core 1, the weld is shaped without defects, the surface of the continuous sucker rod is smooth, reducing friction damage between the continuous sucker rod and the well wall, and has excellent corrosion resistance, which significantly extends the service life.

[0164] After being immersed in crude oil for 1000 hours under ultra-deep well conditions of 160℃ and 25MPa, the tensile strength retention rate is ≥84%, which is significantly improved compared with ordinary sucker rods. Its high strength and high stability characteristics can effectively reduce the risk of sucker rod breakage and failure in ultra-deep wells. It is suitable for ultra-deep well oil production operations with a well depth of more than 3000m, filling the application gap of traditional sucker rods in the field of ultra-deep wells.

[0165] The carbon fiber and metal composite continuous sucker rod prepared by the production process of this invention has the advantages of being lightweight, high-strength, highly corrosion-resistant, and having good structural stability. It can effectively adapt to the oil production operation needs under complex well conditions such as deep oil layers, ultra-deep wells, directional wells, high-sulfur and high-salinity oil reservoirs, and high temperature and high pressure.

[0166] The continuous sucker rod produced by this invention is lighter in weight, which can reduce axial tensile force and stroke loss, and reduce the risk of rod fatigue fracture. At the same time, it has stronger corrosion resistance and temperature resistance, and can operate stably for a long time in harsh corrosive environments and high temperature and high pressure conditions, significantly extending its service life and reducing the maintenance cost and downtime of oil production operations.

[0167] The production process of this invention achieves precise covering of the metal protective jacket 2 through a dedicated shaping device 3, solving the technical problem of uneven seam alignment at the metal protective jacket 2 during the roll forming process of traditional composite sucker rods. The multi-directional roll forming mechanism 5 in the shaping device 3 can roll and shape the metal strip step by step, so that the metal strip is rolled into a curved surface structure with an equidistant narrowing diameter, and is tightly fitted with the covering core 1. The seam shaping mechanism 6 can further shape the seam of the metal strip to ensure welding quality.

[0168] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A manufacturing process for a continuous sucker rod composed of carbon fiber and metal, characterized in that: Includes the following steps: S1: Raw material preparation, including carbon fiber filaments, reinforcing fiber filaments, resin liquid and metal strips; S2: Preparation of composite fiber monofilament yarn: Carbon fiber filaments and reinforcing fiber filaments are twisted together by a twisting machine to obtain composite fiber monofilament yarn; S3: Core preparation. The composite fiber core can be made by directly forming a single composite fiber strand, or by twisting multiple composite fiber strands together using a stranding machine. S4: Impregnate with resin solution, using resin solution as impregnation medium to impregnate and coat the composite fiber core, to obtain a polymer-fiber composite core; S5: The filling layer is coated and cured. The resin liquid is forcefully extruded into the fiber gaps of the polymer-fiber composite core under high pressure by an extruder to form a filling layer, and then cured in a tunnel curing oven to obtain the coated core. S6: Shaping and covering the metal protective jacket, the metal strip to be rolled and the covering core are simultaneously fed into the shaping device for multi-directional rolling processing, so that the metal strip is tightly attached to the outer surface of the covering core. The metal strip is rolled and shaped step by step by multiple cross rolling components. At the same time, the gantry robot operates the top pressing shaping plate to move back and forth within the rolling stroke of each level of cross rolling components, so as to realize dynamic double shaping of the cylindrical gap of the metal strip after rolling, so that the metal strip forms a metal protective jacket with high seam neatness. S7: Welding seam, mark the seam of the metal protective jacket as the weld seam, and use argon arc welding process to butt weld the weld seam to form a composite sucker rod blank; S8: Weld heat treatment. The welded composite sucker rod blank is sent into an induction heating furnace to perform continuous induction heat treatment on the weld. The internal stress of the weld is eliminated by tempering the weld to obtain a continuous sucker rod of carbon fiber and metal composite. At the same time, the workpiece traction operation in S6 to S8 is realized by an automatic metal tube pulling machine. S9: Finished product inspection. The appearance, dimensional accuracy, tensile strength and corrosion resistance of the continuous sucker rod are tested in sequence. After passing the test, the rod is cut to the set length as required and wound onto a special plate to obtain the finished sucker rod body.

2. The manufacturing process of a continuous sucker rod composed of carbon fiber and metal according to claim 1, characterized in that: The dynamic double shaping includes two synergistic shaping methods: dynamic shaping and double shaping. The dynamic shaping adapts to the cylindrical gaps formed by the roll forming of the metal strip with equal spacing and narrowing after roll forming. The double shaping works in sync to improve the shaping degree of the inner and outer sides of the cylindrical gap. Dynamic shaping is achieved by a truss robot manipulating the top-pressing shaping plate to reciprocate within the rolling stroke of the cross roller pressing assembly. Based on the decreasing rolling shaft diameter of each section of the cross roller pressing assembly, the shaping spacing and shaping angle of the top-pressing shaping plate are adjusted in real time to ensure that the shaping action and the cylindrical surface gap shape of the metal strip after rolling are in real time throughout the entire process. The dual shaping is achieved by setting each pair of top-pressure shaping plates in a front-to-back symmetrical layout. A single top-pressure shaping plate can be inserted into the gap inside the metal protective jacket to form an inner support to complete the first shaping, or it can be attached to the edge of the seam of the metal protective jacket to form an outer pressure to complete the second shaping. By relying on the combination of inner support and outer pressure, the precise shaping and docking at the seam of the cylindrical surface can be achieved.

3. The manufacturing process of a continuous sucker rod composed of carbon fiber and metal according to claim 1, characterized in that: The specific method for preparing the composite fiber monofilament in step S2 is as follows: S21: Material selection and structural design of composite fiber single strand yarn. The composite fiber single strand yarn adopts a core-sheath composite structure design. The core layer is made of multiple carbon fiber filaments, and the outer layer is covered with reinforcing fiber filaments. The reinforcing fiber filaments are one or more of aramid fiber, glass fiber, basalt fiber, and alumina fiber. The structure and mechanical properties of the single strand yarn are optimized by complementing the material properties of the core layer and the outer layer. S22: To produce a composite fiber monofilament, multiple carbon fiber filaments are twisted together by a stranding machine to form an inner fiber filament. The outer layer of the inner fiber filament, which serves as the core layer, is then twisted together by a stranding machine to wrap multiple reinforcing fiber filaments, thus obtaining the composite fiber monofilament.

4. A shaping device for a continuous sucker rod made of carbon fiber and metal composite, used in the shaping device of the production process of a continuous sucker rod made of carbon fiber and metal composite as described in any one of claims 1 or 2, characterized in that: It includes a multi-directional rolling mechanism and several stitch shaping mechanisms. The stitch shaping mechanism is located on top of the multi-directional rolling mechanism, and its working end is in abutting fit with the cylindrical surface of the metal protective jacket. The seam shaping mechanism includes multiple truss robots that move horizontally and reciprocally above the metal strip in the rolling process. Each truss robot is equipped with a shaping adjustment component at its telescopic end. The bottom of the shaping adjustment component abuts against the cylindrical gap of the metal protective jacket to shape the seam of the metal protective jacket and ensure welding quality. The shaping and adjusting assembly includes a hollow platform mounted on the telescopic end of the gantry manipulator. Two rotating shafts are movably mounted inside the hollow platform via bearings. Gears on the same side of the two rotating shafts are staggered and mesh with racks arranged vertically. One end of each rack is connected to a servo electric push rod, and the other end slides into a sliding engagement slot on the hollow platform. Angle adjusting rods mounted on the two rotating shafts are arranged in an X-shape, with a servo motor B mounted at the bottom of each rod. A top-pressure shaping plate is circumferentially fixed to the output shaft of servo motor B. The two top-pressure shaping plates are arranged symmetrically and interlock at the cylindrical seam formed by the metal protective jacket and the covering core. This structural adaptation achieves internal support and external pressure shaping at the cylindrical seam of the metal protective jacket, completing the shaping and fine-tuning of the seam area of ​​the metal protective jacket.

5. The shaping device for a continuous sucker rod made of carbon fiber and metal composite according to claim 4, characterized in that: The multi-directional roller pressing mechanism includes multiple sets of cross roller pressing assemblies and one set of inclined roller pressing assemblies. The roller pressing diameter of the multiple sets of cross roller pressing assemblies decreases along the feeding direction. The fixed roller and the moving roller of the cross roller pressing assembly are vertically abutted against both sides of the metal strip. The two ends of the fixed roller are mounted on the vertical support frame through bearings, and the two ends of the moving roller are mounted on the lead screw nut through bearings. The lead screw nut is connected to the ball screw drive. One end of the ball screw is equipped with a servo motor A, and the ball screw is installed inside the vertical support frame. A bidirectional ball screw slide is installed on one side of the vertical support frame. A set of roller pressing wheels is mounted on the bidirectional ball screw slide, and the roller pressing wheels are horizontally abutted against both sides of the metal strip.

6. The shaping device for a continuous sucker rod made of carbon fiber and metal composite according to claim 5, characterized in that: The inclined roller pressing assembly includes a hollow frame, which is installed on one side of the cross roller pressing assembly. A servo motor C is installed on the hollow frame. The output end of the servo motor C is connected to a worm gear, which drives the worm gear to rotate while simultaneously driving the hollow worm wheel installed on the hollow frame to rotate. A pair of swing rollers are installed radially on the hollow worm wheel, and the swing rollers are in movable contact with the outer side of the metal strip.

7. The shaping device for a continuous sucker rod made of carbon fiber and metal composite according to claim 6, characterized in that: The feeding end of the shaping device is equipped with a guide element, which is a bellows with a tapered structure. The large opening end of the tapered surface of the guide element faces the opposite direction to the feeding end of the shaping device, and the small opening end of the tapered surface faces the feeding end of the shaping device. The inside of the guide element is in movable contact with the unwound core and the metal strip, which can play a limiting and guiding role for the core placed on the metal strip.

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