Composite pipe fitting manufacturing process and composite carbon fiber pipe fitting

Abstract

The invention relates to a composite pipe fitting manufacturing process and a composite carbon fiber pipe fitting. A base body pipe fitting is inserted into a plastic pipe fitting to form a first assembly; end sealing clamps are arranged at the two ends of the first assembly respectively to form a second assembly; connecting a connecting assembly into a preset insertion hole in the plastic pipe fitting; the vacuum glue injection machine is connected with the connecting assembly; a vacuumizing device of the vacuum glue injection machine is started, and the gap layer is vacuumized to a preset vacuum degree; the vacuumizing device is closed, a glue valve of the vacuum glue injection machine is opened, and preset glue in the glue raw material bin is injected into the gap layer; the second assembly is placed in preset curing equipment for glue curing; and after curing is completed, the end sealing clamps are taken out of the two ends of the first assembly, and the composite pipe fitting is obtained. The manufacturing process is simple, the processing difficulty is low, and the production efficiency is high.

Description

Technical Field

[0001] The present invention relates to the technical field of pipe fitting processing, and particularly to a manufacturing process for composite pipe fittings and composite carbon fiber pipe fittings. Background Art

[0002] Due to the high strength and lightweight characteristics of carbon fiber pipe fittings, they are widely used in fields such as aerospace, automotive, two-wheel vehicles, and sports equipment. Carbon fiber pipe fittings not only have excellent longitudinal tensile strength but also good corrosion resistance and thermal stability, greatly promoting the lightweight design and performance improvement of related products.

[0003] However, despite the excellent performance of carbon fiber pipe fittings in many aspects, the inherent brittleness and insufficient transverse strength of carbon fiber pipe fittings have always restricted their wider application. Specifically, when carbon fiber pipe fittings are subjected to external impacts or complex stress environments (such as bending, torsion, or lateral forces), they are prone to sudden fracture, which poses a potential threat to structural safety and reliability. In addition, the transverse stiffness of carbon fiber pipe fittings is relatively weak, making it difficult to effectively resist transverse loads, limiting their application in scenarios that require high lateral pressure resistance or torsional resistance performance.

[0004] To solve the above problems, various methods for enhancing the performance of carbon fiber pipe fittings have been explored in the prior art, such as changing the fiber arrangement. However, these methods often have deficiencies such as complex processes and high costs. Therefore, it is particularly important to develop a manufacturing process that can effectively enhance the transverse strength and toughness of carbon fiber pipe fittings, while maintaining their lightweight and high-strength characteristics, and having a simple process and controllable cost. Summary of the Invention

[0005] The main object of the present invention is to provide a manufacturing process for composite pipe fittings and composite carbon fiber pipe fittings, which is used to solve the problems of complex existing processes and excessive costs for enhancing the transverse strength and toughness of pipe fittings.

[0006] To achieve the above object, the first aspect of the present invention provides a manufacturing process for composite pipe fittings, including the following steps:

[0007] Insert a base pipe fitting into the hollow internal space of a plastic pipe fitting to form a first assembly. In the first assembly, there is a gap between the outer wall of the base pipe fitting and the inner wall of the plastic pipe fitting;

[0008] Seal end clamps are respectively arranged at both ends of the first assembly to form a second assembly; the seal end clamp includes a seal end body and an interlayer assembly connected to each other. When the seal end clamp is arranged at the end of the first assembly, the interlayer assembly is located on the side of the seal end body close to the first assembly, and the interlayer assembly is embedded into the gap between the outer wall of the base pipe fitting and the inner wall of the plastic pipe fitting to form a gap layer, and the seal end body closes the end of the first assembly to isolate it from the outside air;

[0009] A connection assembly is inserted into a preset jack on the plastic pipe fitting. The first end of the connection assembly is located inside the plastic pipe fitting, and the second end of the connection assembly is located outside the first assembly; the number of the preset jacks is at least two;

[0010] One end of a first conduit of a vacuum injection glue machine is connected to the second end of one of the connection assemblies, and one end of a second conduit of the vacuum injection glue machine is connected to the second end of another connection assembly;

[0011] The vacuum pumping device of the vacuum injection glue machine is turned on to pump the inside of the gap layer to a preset vacuum degree; the vacuum pumping device is connected to the other end of the first conduit;

[0012] The vacuum pumping device is turned off, and the glue valve of the vacuum injection glue machine is turned on to inject a preset glue in the glue raw material bin into the gap layer until the gap layer is filled with the preset glue; the glue valve is arranged on the second conduit, and the glue raw material bin is connected to the other end of the second conduit;

[0013] The second assembly is placed in a preset curing device for glue curing;

[0014] After curing is completed, the seal end clamps are taken out from both ends of the first assembly to obtain the composite pipe fitting.

[0015] Further, before the step of inserting the connection assembly into the preset jack on the plastic pipe fitting, it includes:

[0016] Mark the hole opening positions on the plastic pipe fitting of the first assembly;

[0017] A hole is made at the hole opening position through a hole punching tool to obtain a preset jack. The preset jack penetrates through the plastic pipe fitting and does not penetrate to the base pipe fitting.

[0018] Further, the preset jack adopts one of a straight hole, an inclined hole, and a tapered hole.

[0019] Further, the step of inserting the connection assembly into the preset jack on the plastic pipe fitting includes:

[0020] The inner wall of the preset jack is provided with internal threads, and the first end of the connection component is provided with external threads. The first end of the connection component is screwed into the preset jack, so that the connection component is detachably connected to the plastic pipe fitting.

[0021] Further, the step of injecting the preset glue in the glue raw material bin into the gap layer until the gap layer is filled with the preset glue includes:

[0022] During the process of injecting the preset glue into the gap layer, the second assembly is rotated in a preset rotation manner until the gap layer is filled with the preset glue.

[0023] Further, the preset rotation manner includes horizontally placing the second assembly for a first period of time. When horizontally placed, the second end of the connection component is located above the horizontal plane of the second assembly;

[0024] Rotate the second assembly to make the second assembly vertically placed for a second period of time. When vertically placed, the connection component for injecting the preset glue is located above the side of the second assembly.

[0025] Further, the interlayer assembly is of an annular conical structure. In the second assembly, the interlayer assembly is inserted into the gap between the outer wall of the base pipe fitting and the inner wall of the plastic pipe fitting, so that the base pipe fitting and the plastic pipe fitting are coaxial, and the gap layer has a uniform thickness.

[0026] Further, the surface material of the interlayer assembly includes at least one of polyethylene, polypropylene, polytetrafluoroethylene, rubber, glass, ceramic, and smooth metal.

[0027] Further, the viscosity range of the preset glue is 3000 - 200000 cp.

[0028] The second aspect of the present invention provides a composite carbon fiber pipe fitting, wherein the base pipe fitting is made of a carbon fiber pipe fitting and is obtained by adopting the manufacturing process of the above composite pipe fitting.

[0029] The composite pipe fitting manufacturing process and the composite carbon fiber pipe fitting provided by the present invention have the following beneficial effects:

[0030] By combining the matrix pipe fitting with the plastic pipe fitting, a structure with complementary advantages of the inner and outer layer materials is formed. The plastic pipe fitting increases the lateral strength and toughness of the matrix pipe fitting, effectively preventing local buckling or damage of the matrix pipe fitting when stressed, and improving the load-bearing capacity and anti-deformation ability of the overall pipe fitting. In the present invention, by setting end-clamping fixtures at both ends of the first assembly formed by the matrix pipe fitting and the plastic pipe fitting, and using the vacuum injection glue technology to fill the glue into the gap between the matrix pipe fitting and the plastic pipe fitting, a composite pipe fitting with high strength and high toughness is obtained, thereby significantly improving the lateral strength and impact resistance of the matrix pipe fitting. The process is simple, the processing difficulty is low, and the production efficiency is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a process flow chart of manufacturing the composite pipe fitting in an embodiment;

[0032] Figure 2 It is a schematic diagram of the manufacturing equipment of the composite pipe fitting in an embodiment;

[0033] Figure 3 It is a schematic cross-sectional structure diagram of the second assembly in an embodiment;

[0034] Figure 4 It is a schematic longitudinal-sectional structure diagram at the connection assembly in an embodiment;

[0035] Figure 5 It is a schematic structure diagram of the end-clamping fixture in an embodiment;

[0036] Figure 6 It is a schematic cross-sectional structure diagram of the end-clamping fixture in an embodiment.

[0037] Reference Numerals in the Drawings:

[0038] 1: First assembly; 11: Matrix pipe fitting; 12: Plastic pipe fitting;

[0039] 2: End-clamping fixture; 21: End-clamping main body; 211: First surface of the end-clamping main body; 212: Second surface of the end-clamping main body; 22: Interlayer assembly; 221: First end face of the interlayer assembly; 222: Second end face of the interlayer assembly; 23: Handle;

[0040] 3: Connection assembly; 301: First end of the first connection assembly; 302: Second end of the first connection assembly;

[0041] 4: Vacuum pumping device; 41: Vacuum pump; 42: Glue buffer tank;

[0042] 5: Glue valve; 6: Glue raw material bin; 61: Piston; 7: Second conduit; 8: First conduit; 9: Vacuum valve.

[0043] The realization, functional features, and advantages of the present invention will be further described in conjunction with embodiments with reference to the accompanying drawings. Detailed Embodiments

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this invention belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" and any variations thereof in the specification and claims of this invention and the above drawings are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification and claims of this invention or the above drawings are used to distinguish different objects and not to describe a specific order.

[0045] Reference to "embodiment" herein means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present invention. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0046] To enable those skilled in the technical field to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0047] Refer to Figures 1-3 , an embodiment of the present invention discloses a manufacturing process for a composite pipe fitting, including the following steps:

[0048] S1. Insert the base pipe fitting 11 into the hollow internal space of the plastic pipe fitting 12 to form a first assembly 1. In the first assembly 1, there is a gap between the outer wall of the base pipe fitting 11 and the inner wall of the plastic pipe fitting 12.

[0049] S2. Set end-sealing clamps 2 at both ends of the first assembly 1 to form a second assembly; the end-sealing clamp 2 includes an end-sealing main body 21 and an interlayer assembly 22 connected to each other. When the end-sealing clamp 2 is set at the end of the first assembly 1, the interlayer assembly 22 is located on the side of the end-sealing main body 21 close to the first assembly 1, and the interlayer assembly 22 is embedded in the gap between the outer wall of the base pipe fitting 11 and the inner wall of the plastic pipe fitting 12 to form a gap layer, and the end-sealing main body 21 seals the end of the first assembly 1 to isolate it from the outside air.

[0050] S3. Insert the connection component 3 into the preset jacks on the plastic pipe fitting 12. The first end 301 of the connection component is located inside the plastic pipe fitting 12, and the second end 302 of the connection component is located outside the first assembly 1. The number of the preset jacks is at least two.

[0051] S4. Connect one end of the first conduit 8 of the vacuum injection molding machine to the second end 302 of one of the connection components, and connect one end of the second conduit 7 of the vacuum injection molding machine to the second end 302 of the other connection component.

[0052] S5. Turn on the vacuum pumping device 4 of the vacuum injection molding machine to pump the inside of the gap layer to a preset vacuum degree. The vacuum pumping device 4 is connected to the other end of the first conduit 8.

[0053] S6. Turn off the vacuum pumping device 4 and turn on the glue valve 5 of the vacuum injection molding machine to inject the preset glue in the glue raw material bin 6 into the gap layer until the gap layer is filled with the preset glue. The glue valve 5 is arranged on the second conduit 7, and the glue raw material bin 6 is connected to the other end of the second conduit 7.

[0054] S7. Place the second assembly in a preset curing device for glue curing.

[0055] S8. After curing is completed, take out the end-sealing fixture 2 from both ends of the first assembly 1 to obtain the composite pipe fitting.

[0056] In this embodiment, in the above step S1, in the above first assembly 1, the matrix pipe fitting 11 and the plastic pipe fitting 12 are coaxial pipe fittings. For cylindrical pipe fittings, the inner diameter of the plastic pipe fitting 12 is larger than the inner diameter of the matrix pipe fitting 11. Insert the matrix pipe fitting 11 into the plastic pipe fitting 12 from one end of the plastic pipe fitting 12. At this time, in the formed first assembly 1, there is a gap between the matrix pipe fitting 11 and the plastic pipe fitting 12, but the two can still move relative to each other, and the upper and lower gaps between the pipe fittings are not uniform. The lengths of the matrix pipe fitting 11 and the plastic pipe fitting 12 should be basically close, preferably pipe fittings of the same length. The matrix pipe fitting 11 can be, for example, a carbon fiber pipe fitting, and the plastic pipe fitting 12 can be, for example, a PC pipe fitting. In a specific embodiment, the wall thickness range of the matrix pipe fitting 11 is 0.1 mm to 10 mm, and the inner diameter range of the matrix pipe fitting 11 is 10 mm to 60 mm; the thickness of the plastic pipe fitting 12 is 0.1 mm to 10 mm.

[0057] In the above step S2, set the end-sealing fixtures 2 at both ends of the first assembly 1 to seal both ends of the first assembly 1, which is beneficial to the realization of the subsequent vacuum pumping step. Refer to Figures 5-6, in a specific embodiment, the end - sealing fixture 2 includes an end - sealing main body 21 and an intercalation component 22 which are connected to each other. The end - sealing main body 21 includes a first face and a second face which are opposite to each other. The first face 211 and the second face 212 of the end - sealing main body are both closed figures without internal cavities. The intercalation component 22 includes a first end face and a second end face which are opposite to each other. The first end face 221 of the intercalation component is connected to the second face 212 of the end - sealing main body; the area of the second end face 222 of the intercalation component is smaller than the area of the first end face 221 of the intercalation component. The first projection of the first end face 221 of the intercalation component on the second face 212 of the end - sealing main body is within the second face 212 of the end - sealing main body, and the second projection of the second end face 222 of the intercalation component on the second face 212 of the end - sealing main body is within the outer contour of the second end face 222 of the intercalation component. The intercalation component 22 and the end - sealing main body 21 can be integrally connected; or they can be fixed through connection means such as fasteners (such as bolts, screws, etc., not shown in the figure), so that the intercalation component 22 can be flexibly installed or disassembled as needed. The area of the second end face 222 of the intercalation component is smaller than the area of its first end face, so that when the intercalation component 22 is inserted into the gap layer inside the first assembly 1, it is easy to insert, and it can be applicable to the first assembly 1 with different gap - layer thicknesses, with wide applicability. Moreover, it can gradually reduce the occupation of the gap - layer space. Since the area of the second end face is smaller than the area of the first end face, the edge of the intercalation component 22 is in a shape that gradually shrinks inward. When the intercalation component 22 is inserted into the gap layer of the first assembly 1, it will finally be positioned at a position matching the thickness of the gap layer, and the part of its front end extending into the gap layer will not contact the edge of the first assembly 1, thus avoiding the problem that the edge of the first assembly 1 cannot be glued. Specifically, in use, first insert the second end face of the intercalation component 22 of the pipe - fitting end - sealing fixture 2 into the gap of the first assembly 1 until the intercalation component 22 penetrates to a position where its thickness matches the gap layer. Since the plastic pipe 12 has a certain elasticity, after the intercalation component 22 is inserted to a proper position, the intercalation component 22 is connected to the first assembly 1 through static friction, and the end - sealing main body 21 further realizes the sealing of the end face of the first assembly 1. In a specific embodiment, the thickness of the gap layer is 0.01 mm - 3 mm.

[0058] In the above steps S3 - S4, the vacuum injection - glue machine specifically includes a vacuum - pumping device 4, a first conduit 8, a second conduit 7, and a glue raw - material bin 6. A vacuum - pumping valve 9 is arranged on the first conduit 8, and a glue valve 5 is arranged on the second conduit 7. One end of the first conduit 8 is provided with a connection component 3, and one end of the second conduit 7 is provided with a connection component 3. By inserting the two connection components 3 into the preset jacks of the plastic pipe 12 respectively, the connection between the second assembly and the vacuum injection - glue machine is realized.

[0059] Since the conduits of vacuum injection molding machines are usually made of plastic tube materials, it is somewhat difficult to directly insert them into the preset jacks, and they are prone to falling off from the preset jacks during vacuum pumping. The connection assembly 3 is provided for connection to ensure a tight connection between the conduit and the preset jack. The connection assembly 3 is made of a rigid material and is convenient for inserting into the conduit of the vacuum injection molding machine. The connection assembly 3 has a hollow structure.

[0060] In the above steps S5 - S6, the vacuum pumping device 4 is turned on to pump the second assembly to a preset vacuum level, then the vacuum pumping device 4 is turned off, the glue valve 5 is opened, and the glue in the glue raw material bin 6 is injected into the second assembly; when the injection space in the second assembly is filled, a small amount of excess glue will enter the first conduit 8. At this time, the vacuum pumping valve 9 is closed, and the glue valve 5 is closed to stop the glue injection. Then the first conduit 8 and the second conduit 7 are removed from the vacuum pumping device 4 and the glue raw material bin 6.

[0061] Preferably, referring to Figure 1 , the vacuum pumping device 4 includes a vacuum pump 41 and a glue buffer tank 42. The vacuum pump 41 is connected to the glue buffer tank 42, and the glue buffer tank 42 is connected to one end of the first conduit 8. During the glue injection process, to ensure that the gap layer in the second assembly is filled, it is necessary to let a small amount of glue overflow from the first conduit 8 before stopping the glue injection. The glue buffer tank 42 is provided to store the glue that may overflow from the first conduit 8 to prevent excess glue from entering the vacuum pump 41.

[0062] In a specific embodiment, the glue raw material bin 6 is an open - top container without a seal. When injecting glue into the product, the height of the glue raw material bin 6 relative to the product is adjustable. For an open - top container without a seal, when the vacuum pumping is completed and the second valve is opened, the atmospheric pressure of the external air will directly press the glue into the second conduit 7, thus realizing the glue injection. The height of the glue raw material bin 6 can be adjusted according to the glue viscosity. For glue with a higher viscosity, the height of the glue raw material bin 6 relative to the second assembly can be increased to facilitate the glue injection; for glue with a lower viscosity, the height of the glue raw material bin 64 relative to the second assembly can be appropriately decreased to achieve a smooth glue injection.

[0063] In another specific embodiment, the glue raw material bin 6 is a closed container, and a piston 61 is provided on the glue raw material bin 6. The glue in the glue raw material bin 6 is injected into the gap layer in the second assembly through the second conduit 7 by the piston 61. For a closed - type glue raw material bin 6, the glue is injected by the piston 61. For glues with different viscosities, the injection speed of the glue can be adjusted by adjusting the force and speed of pushing and pulling the piston 61.

[0064] In the above step S7, the second assembly connecting the first conduit 8 and the second conduit 7 with the valve in the closed state is placed in a preset curing device for curing. The type of the preset curing device and the specific curing conditions can be determined according to the selected glue type. After curing is completed, the connecting component 3 is removed from the plastic pipe fitting 12. Even if a small amount of glue adheres to the connecting component 3, it can be screwed out by rotating.

[0065] In the above step S8, the end-capping fixture 2 is removed to obtain a composite pipe fitting. The end-capping fixture 2 needs to select materials according to the glue, and preferably uses materials with low surface energy, such as polyethylene, polypropylene, polytetrafluoroethylene, rubber, glass, ceramics, or metals with a smooth surface, so as to facilitate the removal of the pipe fitting end-capping fixture 2 after the glue is cured.

[0066] In the embodiment of the present invention, by arranging end-capping fixtures 2 at both ends of the first assembly 1 formed by the base pipe fitting 11 and the plastic pipe fitting 12, and using the above specific vacuum injection glue technology to fill the glue into the gap between the base pipe fitting 11 and the plastic pipe fitting 12, a high-strength and high-toughness composite material layer is prepared, thereby significantly improving the lateral strength and impact resistance of the base pipe fitting 11. The process is simple, the processing difficulty is low, and the production efficiency is high.

[0067] In a specific embodiment, before the step S3 of connecting the connecting component 3 to the preset jack on the plastic pipe fitting 12, it includes:

[0068] S01. Mark the opening position on the plastic pipe fitting 12 of the first assembly 1;

[0069] S02. Use a punching tool to punch an opening at the opening position to obtain a preset jack, the preset jack penetrates the plastic pipe fitting 12 and does not penetrate to the base pipe fitting 11.

[0070] In this embodiment, the position of the above preset jack is located at both end positions of the first assembly 1, so as to facilitate the glue in the subsequent glue injection process to be injected from the end of the second assembly, and avoid local cavities caused by the difficulty of glue penetration in local areas. Preferably, different hole diameters can be selected for different products, for example, the hole diameter can be less than or equal to 5 mm. The above punching tool can adopt the punching tools in the prior art, and the present invention does not make special limitations on the type of the punching tool, as long as the effect of opening the above preset jack can be achieved.

[0071] In a specific embodiment, the above-mentioned preset jack can be a straight hole, an inclined hole, a conical hole, etc. Among them, the straight hole is convenient for processing, the inclined hole can adjust the direction of glue injection, and the conical hole can be a hole with a smaller upper part and a larger lower part. Thus, from the appearance of the plastic pipe fitting 12, it is a small hole opened, minimizing the impact on the product appearance as much as possible. However, the hole diameter gradually becomes larger towards the inner layer of the plastic pipe fitting 12, which is conducive to the rapid injection of glue. Preferably, threads are provided inside the preset jack.

[0072] In a specific embodiment, the step S3 of connecting the connection component 3 to the preset jack on the plastic pipe fitting 12 includes:

[0073] S301. Internal threads are provided on the inner wall of the preset jack, and external threads are provided at the first end 301 of the connection component. The first end 301 of the connection component is screwed into the preset jack, so that the connection component 3 is detachably connected to the plastic pipe fitting 12.

[0074] Correspondingly, referring to Figure 4 , threads are provided inside the preset jack, and the first end 301 of the connection component is stably connected to the preset jack by means of thread connection. Since the first conduit 8 and the second conduit 7 are usually made of plastic material, and the plastic material has elasticity, the second end 302 of the connection component can be directly inserted into the first conduit 8 and the second conduit 7. Through the above method, reliable connections of the first conduit 8, the connection component 3 and the preset jack, and the second conduit 7, the connection component 3 and the preset jack are achieved.

[0075] In a specific embodiment, the step S6 of injecting the preset glue in the glue raw material bin 6 into the gap layer until the gap layer is filled with the preset glue includes:

[0076] S601. During the process of injecting the preset glue into the gap layer, the second assembly is rotated in a preset rotation manner until the gap layer is filled with the preset glue.

[0077] By means of rotational glue injection, it can be ensured that the preset glue is injected into all areas of the gap layer, avoiding air bubbles caused by local glue leakage. It can also speed up the spreading speed of the glue in the gap layer to a certain extent.

[0078] In a specific embodiment, the preset rotation manner includes horizontally placing the second assembly for a first period of time. When horizontally placed, the second end 302 of the connection component is located above the horizontal plane of the second assembly; when horizontally placed, the axis of the first assembly 1 is in a substantially horizontal state with the ground, and the sealing end fixture 2 is located on the left and right sides of the first assembly 1.

[0079] Rotate the second assembly again so that the second assembly is vertically placed for a second period of time. When vertically placed, the connecting component 3 for injecting the preset glue is located above the side of the second assembly; when vertically placed, the axis of the first assembly 1 is in a state substantially perpendicular to the ground, and the end sealing fixtures 2 are located on the upper and lower sides of the first assembly 1.

[0080] In a specific embodiment, the interlayer assembly 22 is of an annular conical structure. In the second assembly, the interlayer assembly 22 is inserted into the gap between the outer wall of the base pipe fitting 11 and the inner wall of the plastic pipe fitting 12, so that the base pipe fitting 11 and the plastic pipe fitting 12 are coaxial, and the gap layer has a uniform thickness.

[0081] In a specific embodiment, the interlayer assembly 22 includes an opposite first end face and a second end face. In use, the second end face 222 of the interlayer assembly is first inserted into the gap layer, wherein the ratio range of the area of the second end face 222 of the interlayer assembly to the area of the first end face 221 of the interlayer assembly is 0.5 - 0.99. By setting a reasonable ratio range between the areas of the two end faces of the interlayer assembly 22, on the one hand, the interlayer assembly 22 can be easily inserted into the pipe fitting and reach the required sealing depth; on the other hand, it will not damage the pipe fitting or cause excessive loss of the glue layer due to excessive insertion.

[0082] In a specific embodiment, the width range of the interlayer assembly 22 is 5 mm - 50 mm, and the width is the distance from the first end face 221 of the interlayer assembly to the second end face 222 of the interlayer assembly. In this embodiment, by setting the above reasonable width range of the interlayer assembly 22, on the one hand, the interlayer assembly 22 can be easily inserted into the pipe fitting and reach the required sealing depth; on the other hand, it will not damage the pipe fitting or cause excessive loss of the glue layer due to excessive insertion.

[0083] In a specific embodiment, the thickness range of the end sealing main body 21 is 0.1 mm - 10 mm, and the thickness is the distance from the first face 211 of the end sealing main body to the second face 212 of the end sealing main body. In this embodiment, by setting the above reasonable thickness range of the end sealing main body 21, the encapsulation main body has a certain structural strength, thereby ensuring that it is not easily damaged during use.

[0084] In a specific embodiment, a handle 23 is provided on the outer side surface of the end sealing main body 21, so as to facilitate installation and disassembly.

[0085] In a specific embodiment, the surface material of the interlayer assembly 22 includes at least one of polyethylene, polypropylene, polytetrafluoroethylene, rubber, glass, ceramic, and smooth metal.

[0086] After the glue injection is completed, cure the glue and then remove the pipe end capping fixture 2. The capping body 21 and the interlayer assembly 22 of the pipe end capping fixture 2 can be made of the same or different materials. For the capping body 21, it can be metal, glass, plastic, ceramic, etc.; for the interlayer assembly 22, the material needs to be selected according to the glue, and it is preferably made of a material with a low surface energy. For example, it can be selected from polyethylene, polypropylene, polytetrafluoroethylene, rubber, glass, ceramic, so that it is difficult for the interlayer assembly 22 to bond with the glue or the bonding is not tight, so as to facilitate the removal of the pipe end capping fixture 2 after the glue is cured. Or use a metal with a smooth surface, for example, the surface roughness is not greater than 10 microns, so as to reduce the bonding strength between the interlayer assembly 22 and the glue and make it easy to remove the pipe end capping fixture 2.

[0087] In a specific embodiment, the viscosity range of the preset glue is 3000-200000 cp. Exemplarily, the glue can be epoxy resin glue, polyurethane glue, silicone glue, etc. The specific models of the above epoxy resin glue, polyurethane glue, and silicone glue are not enumerated in the present invention, and those skilled in the art can select from the above types of glues in the prior art according to the specific pipe fitting materials.

[0088] An embodiment of the present invention also discloses another manufacturing process for composite pipe fittings, which is used to simultaneously prepare multiple composite pipe fittings. The manufacturing process of each composite pipe fitting is the same as steps S1-S8 in the foregoing embodiment. The difference is that for the case of simultaneously preparing multiple composite pipe fittings, multiple conduits can be respectively connected to the vacuum pumping device and the glue raw material bin of the vacuum injection machine and connected to the connection components of different composite pipe fittings, thereby greatly improving the production efficiency of manufacturing composite pipe fittings.

[0089] An embodiment of the present invention also discloses a composite carbon fiber pipe fitting, which is manufactured by using the foregoing manufacturing process of the composite pipe fitting, wherein the matrix pipe fitting 11 is a carbon fiber pipe fitting.

[0090] The composite carbon fiber pipe fitting obtained by the above method is firmly adhered by arranging a plastic pipe fitting 12 on the outer layer of the carbon fiber pipe fitting and filling glue in the gap layer between the two, thereby effectively enhancing the lateral strength and impact resistance of the carbon fiber pipe fitting. The presence of the plastic pipe fitting 12 disperses the external load, and its excellent mechanical properties, high mechanical strength and elastic modulus, excellent impact resistance and weather resistance greatly reduce the risk of deformation or fracture of the carbon fiber pipe fitting when it is subjected to lateral or transverse forces, thereby significantly improving the overall structural stability of the carbon fiber pipe fitting.

[0091] Obviously, the embodiments described above are only a part of the embodiments of the present invention, rather than all embodiments. The preferred embodiments of the present invention are shown in the accompanying drawings, but do not limit the patent scope of the present invention. The present invention can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosed content of the present invention more thorough and comprehensive. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions described in the foregoing specific embodiments, or perform equivalent replacements for some of the technical features. Any equivalent structure directly or indirectly using the content of the specification and drawings of the present invention in other related technical fields shall be within the scope of the patent protection of the present invention by the same token.

Claims

1. A process for manufacturing a composite pipe, characterized in that: The steps include: Inserting a base tube into the hollow inner space of the plastic tube to form a first assembly, wherein a gap exists between the outer wall of the base tube and the inner wall of the plastic tube; End-sealing fixtures are respectively arranged at both ends of the first assembly to form a second assembly; the end-sealing fixture comprises an end-sealing body and an intercalation component which are connected to each other; when the end-sealing fixture is arranged at the end of the first assembly, the intercalation component is located at a side of the end-sealing body close to the first assembly, the intercalation component is embedded in the gap between the outer wall of the base tube and the inner wall of the plastic tube to form a gap layer, and the end-sealing body seals the end of the first assembly to isolate it from the outside air; A connection component is connected to a preset plug hole on the plastic pipe, wherein a first end of the connection component is located inside the plastic pipe, and a second end of the connection component is located outside the first assembly; the number of the preset plug holes is at least two; Connecting one end of the first conduit of the vacuum glue injection machine to the second end of one of the connection components, and connecting one end of the second conduit of the vacuum glue injection machine to the second end of another of the connection components; Turning on the vacuum device of the vacuum glue injection machine to evacuate the gap layer to a preset vacuum degree; the vacuum device is connected to the other end of the first conduit; The vacuum device is closed, and the glue valve of the vacuum glue injection machine is opened to inject the preset glue in the glue raw material bin into the gap layer until the gap layer is filled with the preset glue; the glue valve is arranged on the second conduit, and the glue raw material bin is connected to the other end of the second conduit; placing the second assembly in a preset curing device to cure the glue; After curing is completed, the end-sealing fixtures are taken out from both ends of the first assembly to obtain the composite pipe.

2. The process for manufacturing a composite pipe according to claim 1, characterized in that: Before the step of inserting the connection assembly into the preset socket on the plastic pipe, the method includes: Marking the opening position on the plastic pipe of the first assembly; A hole is punched at the hole opening position by a punching tool to obtain a preset insertion hole, and the preset insertion hole passes through the plastic pipe fitting but does not penetrate to the base pipe fitting.

3. The process for manufacturing a composite pipe according to claim 2, characterized in that: The preset insertion hole is one of a straight hole, an inclined hole and a tapered hole.

4. The process for manufacturing a composite pipe according to claim 1, characterized in that: The step of inserting the connection component into the preset socket on the plastic pipe comprises: The inner wall of the preset plug hole is provided with an internal thread, and the first end of the connecting component is provided with an external thread. The first end of the connecting component is screwed into the preset plug hole so that the connecting component can be detachably connected to the plastic pipe.

5. The process for manufacturing a composite pipe according to claim 1, characterized in that: The step of injecting the preset glue in the glue raw material bin into the gap layer until the gap layer is filled with the preset glue comprises: During the process of injecting the preset glue into the gap layer, the second assembly is rotated in a preset rotation mode until the gap layer is filled with the preset glue.

6. The process for manufacturing a composite pipe according to claim 5, characterized in that: The preset rotation method includes placing the second assembly horizontally for a first period of time, and when placed horizontally, the second end of the connecting component is located above the level of the second assembly; The second assembly is rotated to place the second assembly vertically for a second period of time, and when placed vertically, the connecting component for injecting the preset glue is located above the side of the second assembly.

7. The process for manufacturing a composite pipe according to claim 1, characterized in that: The intercalation component is an annular conical structure. In the second assembly, the intercalation component is inserted into the gap between the outer wall of the base tube and the inner wall of the plastic tube, so that the base tube and the plastic tube are coaxial and the gap layer has a uniform thickness.

8. The process for manufacturing a composite pipe according to claim 1, characterized in that: The surface material of the intercalation component includes at least one of polyethylene, polypropylene, polytetrafluoroethylene, rubber, glass, ceramic, and smooth metal.

9. The process for manufacturing a composite pipe according to claim 1, characterized in that: The viscosity of the preset glue ranges from 3000 to 200000 cp.

10. A composite carbon fiber pipe, characterized in that: The base pipe is a carbon fiber pipe, and is manufactured using the manufacturing process of the composite pipe as described in any one of claims 1-9.

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