A post-positioned glue spraying forming die for a composite material pultrusion profile and a preparation method thereof

Abstract

The application discloses a post-positioned glue pouring forming die for composite material pultruded profiles and a preparation method, relates to the technical field of machining manufacturing, and comprises a connecting rod, a preforming area, a post-positioned glue pouring area and a heating and curing shaping area are sequentially arranged on the connecting rod along the fiber traction advancing direction; the post-positioned glue pouring area is closed and arranged and serves as an independent cavity for fiber glue infiltration, the post-positioned glue pouring area is internally filled with resin, and the two ends of the post-positioned glue pouring area are respectively communicated with the preforming area and the heating and curing shaping area; the preparation method is completed by relying on the die, the dry fiber bundle is first preformed and arranged, then the fiber is locally poured with glue and fully infiltrated in the closed glue pouring area, and finally, the fiber is directly sent into the heating and curing shaping area to be cured and formed. The post-positioned glue pouring forming die for composite material pultruded profiles and the preparation method have the advantages of simple structure, low equipment investment, adoption of normal pressure infiltration mode throughout the whole process, and further reduction of production threshold and use cost.

Description

Technical Field

[0001] This invention relates to the field of machining and manufacturing technology, and in particular to a post-mounted adhesive coating molding die and its preparation method for composite material pultruded profiles. Background Technology

[0002] Pultrusion is one of the mainstream processes for continuous production of composite materials, widely used in the manufacture of various high-performance fiber profiles. Traditional pultrusion generally employs large open or semi-open resin impregnation tanks for fiber impregnation. The reinforcing fibers are drawn from the yarn rack, immersed in the impregnation tank, then combed and shaped by a pre-forming mold, and finally fed into a heated mold for curing. This traditional structure and process have many inherent defects: 1) Significant resin loss and pollution issues: Large open impregnation tanks expose a large area of ​​resin to the air, which can easily cause solvent evaporation, resin moisture absorption / oxidation and deterioration, and even resin pre-gelation. This not only reduces the performance of the resin, but also causes a lot of waste of raw materials. At the same time, volatile substances will pollute the production environment. 2) Poor product quality stability: After the fiber is impregnated, it needs to go through a long open conveying path to reach the heating mold. The ambient temperature will change the resin viscosity, and the fiber bundle is easily disturbed by external forces during the conveying process, resulting in uneven distribution of resin content and impregnation degree inside the fiber bundle, and poor consistency of mechanical properties of the final product. 3) Unsuitable for precision small profile production: For composite profiles with small cross-sectional dimensions and intricate structures, traditional large impregnation tanks combined with long-distance conveying paths are prone to fiber disorder after impregnation. Resin is also prone to accumulate and prematurely gel at the narrow mold cavity entrance, which seriously affects production continuity and profile molding accuracy.

[0003] To address the drawbacks of open impregnation tanks, the industry has gradually introduced front-end injection box molds. This solution adds an independent injection box to the front of the entire pultrusion mold, relying on a dedicated injection machine to achieve pressurized resin injection and fiber impregnation. While front-end injection molds can achieve closed resin delivery and reduce resin volatilization and waste to some extent, they still have significant shortcomings: First, the integration of the entire equipment is highly complex, requiring high-precision injection units, pressure control systems, and other auxiliary equipment, resulting in substantial investment in equipment procurement, installation, and subsequent maintenance. Second, process control is challenging, requiring precise matching of injection pressure, flow rate, and other parameters to the pultrusion speed, demanding high technical skills from operators. Third, the equipment is relatively large, limiting on-site layout and making it unsuitable for lightweight, simplified production lines.

[0004] Currently, the industry still lacks a solution that is simple in structure, requires low equipment investment, and can be applied under normal pressure, avoiding the defects of open-type impregnation while eliminating the need for complex dispensing equipment.

[0005] Developing a post-positioned resin impregnation mold and preparation method for composite pultruded profiles to overcome the shortcomings of existing technologies, such as serious resin waste in open impregnation tanks, uneven impregnation quality, and unsuitability for the production of precision small profiles, has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a post-coating molding die and preparation method for composite pultruded profiles, thereby solving the problems listed in the background art.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: The present invention provides a post-coating molding die for composite pultruded profiles, comprising a connecting rod, wherein a pre-forming area, a post-coating area, and a heat curing and shaping area are sequentially arranged on the connecting rod along the fiber traction direction; The rear-mounted resin coating zone is enclosed and serves as an independent cavity for fiber resin impregnation. The interior of the rear-mounted resin coating zone is filled with resin, and both ends of the rear-mounted resin coating zone are connected to the preforming zone and the heat curing and shaping zone, respectively.

[0008] Preferably, the preforming area includes a first threading plate, the four corners of which are fixedly connected to the ends of the connecting rod, the other end of the connecting rod is fixedly connected to the main fixing plate, and a guide shaft is fixedly installed between the opposite surfaces of the centers of the first threading plate and the main fixing plate. It also includes a second threading plate and a third threading plate. The second threading plate and the third threading plate are fixedly connected to the connecting rod by a fastener. The side of the third threading plate away from the second threading plate is connected to the take-up ring.

[0009] Preferably, an inner guide hollow tube is installed at the center of both the second and third yarn threading plates, and the inner guide hollow tube located between the first and second yarn threading plates has an inner guide oblique opening, and an inner guide felter is installed at the edge of the oblique opening. The inner guide hollow tube is fitted onto the outside of the guide shaft and is coaxial with the guide shaft.

[0010] Preferably, the rear-mounted adhesive application area includes a front mounting plate and a rear mounting plate, and the four corners of the front mounting plate and the rear mounting plate are fixedly connected to the side wall of the connecting rod. A resin-applying cavity is fixedly installed between the opposing surfaces of the front mounting plate and the rear mounting plate. The sidewall of the resin-applying cavity is connected to the resin injection port, which is connected to an external resin supply system via a pipeline.

[0011] Preferably, a front sealing ring is installed on the front mounting plate, and a rear sealing ring is installed on the rear mounting plate; The centers of the front sealing ring and the rear sealing ring are coaxial with the center of the guide shaft; It also includes a yarn support plate, which is located inside the glue-coating cavity and is fixedly installed on the outside of the guide shaft, and the yarn support plate is coaxial with the guide shaft.

[0012] Preferably, the other side of the main fixing plate is fixedly connected to the heat curing and shaping area; An outer guide hollow tube is installed on the main fixing plate. An outer guide oblique opening is opened at one end of the outer guide hollow tube facing the rear mounting plate. An outer guide felt is installed at the outer guide oblique opening. The outer guide hollow tube is fitted onto the outside of the guide shaft, and the guide shaft is coaxial.

[0013] Preferably, the outer guide bevel and the inner guide bevel are arranged in opposite directions.

[0014] A method for preparing post-coating of composite pultruded profiles includes the following steps: Step 1, Fiber feeding: The carbon fiber, glass fiber or basalt fiber reinforced fiber bundle is drawn out from the yarn frame and fed into the preforming area of ​​the mold, passing through the first yarn threading plate, the second yarn threading plate and the third yarn threading plate in sequence. Step 2, Dry Pre-forming: The yarn-gathering loops in the pre-forming zone comb, organize, and gather the loose fiber bundles to complete the initial shape setting in the dry state; Step 3, Sealed Post-Layer Resin Coating: The pre-formed fiber bundles continuously enter the post-layer resin coating zone. The fiber bundles are loosely diffused by the internal yarn support plate and fully contact and wet the resin in the resin coating chamber. After wetting, they re-aggregate. At the same time, the external resin supply system replenishes and circulates the resin in the resin coating zone in real time. Step 4, Heating and Curing: The fiber composite after the resin coating is completed is sent out from the post-coating area and directly enters the heating and curing area, where the resin is cured and the profile is shaped in the high-temperature mold cavity. Step 5, Traction and Material Collection: The cured composite material profiles are continuously pulled out by the traction device to complete the continuous pultrusion production.

[0015] Preferably, the dry preforming process parameters in step two and the resin impregnation process parameters in step three are adjusted independently.

[0016] Compared with the prior art, the beneficial technical effects of the present invention are as follows: 1) Reduce resin consumption and be environmentally friendly: The use of a closed post-coating zone to replace the traditional open large dipping tank significantly reduces the contact area between the resin and the air, effectively suppressing resin solvent evaporation, oxidation and pre-gelling problems, significantly reducing resin consumption, while reducing the emission of harmful volatile substances and improving the production environment.

[0017] 2) Improve product quality consistency: The resin coating area is adjacent to the heating and curing area, which greatly shortens the open transport path of the fibers after impregnation, avoids the influence of ambient temperature and external force disturbance on the fibers and resin, and ensures that the resin impregnation degree and resin content of each fiber are uniform and consistent, and the mechanical properties of the finished profile are stable.

[0018] 3) Process decoupling and high control precision: The fiber arrangement and shaping and resin coating and impregnation are separated into two independent processes. The fibers are first pre-formed with high precision in a dry state, and then sealed resin coating is performed. The process parameters of the two processes can be optimized and adjusted separately to adapt to the production of fiber profiles of different materials and specifications.

[0019] 4) Suitable for precision small profile production: The mold has a compact overall structure and high integration, which solves the problems of fiber disorder, resin accumulation and premature gelation caused by long-path transportation in traditional equipment. It is especially suitable for the stable and continuous production of high-performance composite material profiles such as carbon fiber, glass fiber and basalt fiber with small cross-section and complex structure.

[0020] 5) Strong production continuity: The matching resin circulation system can realize the real-time renewal and replenishment of resin in the coating area, ensuring the stability of the resin state. The whole process can run continuously for a long time, with high production efficiency.

[0021] In summary, the post-positioned resin coating mold and preparation method for composite pultruded profiles of this invention reduce resin volatilization by more than 40% compared to traditional open impregnation tanks, eliminates premature resin gelation, and reduces resin and other raw material waste by more than 50% during the development and production of small-section profiles, achieving a resin utilization rate of over 90%. Compared to front-end injection molds, this production line eliminates the need for an injection machine and pressure control system, reducing equipment investment by more than 35%, simplifying debugging and maintenance, minimizing fiber bundle disturbance throughout the process, ensuring uniform resin distribution across the profile cross-section, significantly improving dimensional accuracy, and providing excellent continuous production stability, fully meeting the mass production requirements for small-section precision glass fiber profiles. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings.

[0023] Figure 1 This is a front view schematic diagram of a post-mounted adhesive coating molding die for a composite pultrusion profile according to the present invention; Figure 2 This is a three-dimensional schematic diagram of a post-positioned adhesive coating molding die for a composite pultruded profile according to the present invention. Figure 1 ; Figure 3 This is a three-dimensional schematic diagram of a post-positioned adhesive coating molding die for a composite pultruded profile according to the present invention. Figure 2 .

[0024] Explanation of reference numerals in the attached drawings: 1-First yarn threading plate; 2-Second yarn threading plate; 3-Third yarn threading plate; 4-Yarn take-up ring; 5-Front mounting plate; 6-Resin injection port; 7-Yarn support plate; 8-Rear mounting plate; 9-Outer felt guide; 10-Inner felt guide; 11-Fixing component; 12-Connecting rod; 13-Glue-applying cavity; 14-Front sealing ring; 15-Rear sealing ring; 16-Outer guide hollow tube; 17-Main fixing plate; 18-Heat curing and shaping area; 19-Guide shaft; 20-Inner guide hollow tube. Detailed Implementation

[0025] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0026] like Figure 1-3 As shown, a post-coating molding die for a composite pultruded profile is characterized by: including a connecting rod 12, on which a pre-forming area, a post-coating area, and a heat curing and shaping area 18 are sequentially arranged along the fiber traction direction; The rear-mounted resin coating zone is enclosed and serves as an independent cavity for fiber resin impregnation. The interior of the rear-mounted resin coating zone is filled with resin, and both ends of the rear-mounted resin coating zone are connected to the preforming zone and the heat curing and shaping zone 18, respectively.

[0027] Specifically, the preforming area includes a first threading plate 1, the four corners of the first threading plate 1 are fixedly connected to the ends of the connecting rod 12, the other end of the connecting rod 12 is fixedly connected to the main fixing plate 17, and a guide shaft 19 is fixedly installed between the opposite surfaces of the centers of the first threading plate 1 and the main fixing plate 17. It also includes a second threading plate 2 and a third threading plate 3. The second threading plate 2 and the third threading plate 3 are fixedly connected to the connecting rod 12 by a fixing member 11. The side of the third threading plate 3 away from the second threading plate 2 is connected to the yarn taking-up ring 4, which is used to comb, gather and preliminarily shape the fiber bundle in a dry environment.

[0028] Specifically, an inner guide hollow tube 20 is installed at the center of both the second yarn threading plate 2 and the third yarn threading plate 3, and an inner guide oblique opening is opened on the inner guide hollow tube 20 located between the first yarn threading plate 1 and the second yarn threading plate 2, and an inner guide felter 10 is installed on the edge of the oblique opening. The inner guide hollow tube 20 is fitted on the outside of the guide shaft 19 and is coaxial with the guide shaft 19.

[0029] Specifically, the rear-mounted adhesive application area includes a front mounting plate 5 and a rear mounting plate 8, and the four corners of the front mounting plate 5 and the rear mounting plate 8 are fixedly connected to the side wall of the connecting rod 12. A glue-spraying cavity 13 is fixedly installed between the opposing surfaces of the front mounting plate 5 and the rear mounting plate 8. The side wall of the glue-spraying cavity 13 is connected to the resin injection port 6, and the resin injection port 6 is connected to an external resin supply system through a pipeline. A front sealing ring 14 is installed on the front mounting plate 5, and a rear sealing ring 15 is installed on the rear mounting plate 8; The centers of the front sealing ring 14 and the rear sealing ring 15 are coaxial with the center of the guide shaft 19; It also includes a yarn support plate 7, which is located inside the resin coating chamber 13 and is fixedly installed on the outside of the guide shaft 19. The yarn support plate 7 is coaxial with the guide shaft 19. At least one yarn support plate is installed inside the resin coating chamber along the fiber travel direction. The yarn passage size of the yarn support plate is larger than the channel size at both ends of the chamber, which can temporarily loosen the fiber bundle to facilitate resin penetration. The resin injection port and resin circulation port are opened on the side wall of the resin coating chamber and are connected to an external resin supply and circulation system through pipelines to realize quantitative resin replenishment and circulation flow.

[0030] Specifically, the other side of the main fixing plate 17 is fixedly connected to the heat curing and shaping area 18, which is a closed high-temperature mold cavity that receives the fiber composite after resin coating and completes the resin heat curing and final shaping of the profile. An outer guide hollow tube 16 is installed on the main fixing plate 17. An outer guide oblique opening is provided at one end of the outer guide hollow tube 16 facing the rear mounting plate 8. An outer guide felter 9 is installed at the outer guide oblique opening. The outer guide hollow tube 16 is fitted on the outside of the guide shaft 19, and the guide shaft 19 is coaxial.

[0031] Specifically, the outer guide bevel and the inner guide bevel are arranged in opposite directions.

[0032] Specifically, a method for preparing a composite pultruded profile with post-coating includes the following steps: Step 1, Fiber feeding: 200 bundles of T700-12K carbon fiber are drawn out from the yarn rack and enter the pre-forming area of ​​the mold. They pass through the first yarn threading plate, the second yarn threading plate, and the third yarn threading plate in sequence. The fiber bundles are arranged in a dry state. Step 2: The fiber bundles are combed and gathered by the take-up ring, and the inner guide felt guides the inner layer fibers to travel along the outside of the guide shaft, initially forming a tubular cross section. At this stage, all fibers are in a dry state, and the pre-forming accuracy is not affected by the resin viscosity. Step 3, Sealed Resin Impregnation: The pre-formed fiber bundle enters the resin impregnation chamber through the front sealing ring. Inside the chamber, two yarn-supporting plates sequentially disperse, gather, disperse, and gather the fiber bundle, allowing the resin to fully penetrate into the fiber bundle. Fresh resin is continuously injected through the resin injection port on the side wall of the chamber. The resin flows from the front to the rear of the chamber, forming a counter-current with the fiber's direction of travel, enhancing the impregnation effect. The front and rear sealing rings control the diameter of the inlet and outlet channels (Φ26mm), allowing the fibers to pass through while effectively preventing resin leakage. Step 4: Heating and curing: The fiber composite that has been coated with adhesive enters the heating and curing zone directly through the post-sealing ring; The curing mold is divided into three temperature zones: Zone 1 130℃ (geling zone), Zone 2 160℃ (main curing zone), and Zone 3 180℃ (post-curing zone). The total curing time is about 3 minutes. The fiber composite is continuously pulled out by the traction device. Step 5, Traction and Material Collection: The cured composite material profiles are continuously pulled out by the traction device to complete the continuous pultrusion production.

[0033] Specifically, the dry preforming process parameters in step two and the resin impregnation process parameters in step three are adjusted independently of each other; The process parameters for a method of preparing post-coating of composite pultruded profiles are shown in the table below:

[0034] Specific comparative examples illustrate the preparation method of open-type impregnated composite pultruded profiles: Step 1, Fiber feeding: 200 bundles of T700-12K carbon fiber are drawn out from the yarn rack and directly fed into the open impregnation tank; Step 2, Impregnation in the impregnation tank: The fiber bundle is pressed into the liquid surface by three grates in the impregnation tank, floats up, and is pressed in again. By bending and moving, the resin contact area is increased. The resin liquid surface in the impregnation tank is open and comes into contact with the air over a large area. After long-term operation, the resin viscosity gradually increases, and a resin pre-gel layer appears on the tank wall and the surface of the grates, which needs to be cleaned manually and regularly. Step 3, Open Conveying and Preforming: After the impregnated fiber bundles are drawn out from the impregnation tank, they need to pass through an open conveying path of about 500mm to reach the preforming mold. During this path, the fiber bundles are exposed to the workshop environment. Changes in ambient temperature and humidity directly change the resin viscosity on the fiber surface. At the same time, the fiber bundles are easily disturbed by airflow under the action of traction force, which can lead to misalignment and affect the uniformity of fiber distribution in the final cross section. The preforming mold combs and shapes the wet fiber bundles after impregnation. However, since the fibers are already coated with resin, the combing accuracy is affected by the resin adhesion force, making it difficult to achieve the high accuracy of dry preforming. Step 4: Heating and curing: The pre-formed fiber composite enters the curing mold and is heated in three zones (130 / 160 / 180℃) as in Example 1. The process parameters for open-type impregnated composite pultruded profiles are shown in the table below:

[0035] The main advantages compared to the traditional impregnation method: Resin utilization and cost: The sealed cavity and sealing ring replace the grate plate, resulting in a very small resin exposure area (only at the injection port), and evaporation loss of <5%; the circulation and renewal system keeps the resin fresh, with a utilization rate of ≥92%. Only about 2.0L of resin is added per cycle. Resin aging risk and continuous production stability: Closed operation, resin is isolated from air, no pre-gelling risk; external circulation system updates resin in real time, constant state, can run continuously for more than 8 hours without shutdown maintenance. Fiber friction and residual strength: The fiber bundle travels in a straight line along the guide axis throughout the entire process. It is only slightly loosened by the yarn support plate in the glue coating chamber, without forced bending. The fiber bending angle is <5°, and the fiber residual strength retention rate is high. Product quality consistency: The resin coating chamber is adjacent to the curing zone (open conveyor section ≈ 0mm), and the fibers directly enter the curing zone after resin impregnation, with no environmental interference throughout the process; the dry preforming has high precision, the resin distribution in the profile cross-section is uniform, and the fiber volume fraction fluctuation is ≤ ±2%; Environmental adaptability: The resin coating chamber is a closed and independent chamber, which isolates the resin from the external environment and is not affected by changes in workshop temperature and humidity, ensuring stable production quality throughout the year. Equipment size and production line layout: The independent dipping tank section is eliminated, and the glue coating chamber is directly integrated between the preforming area and the curing area. The length of the entire production line can be shortened by about 800mm, with a small footprint, making it suitable for compact production line layouts. In summary, the post-coating molding solution of this invention can reduce resin waste and significantly lower operating costs; eliminate pre-gelling, significantly improve the stability of continuous production, reduce friction and bending, and effectively protect the mechanical properties of fibers; the consistency of product mechanical properties is significantly better than that of traditional solutions; stable production in all weather conditions, unaffected by seasons; and the equipment is compact, saving production line space.

[0036] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0037] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A post-mounted adhesive coating molding die for composite pultruded profiles, characterized in that: Includes a connecting rod (12), on which a preforming area, a post-coating area and a heat curing and shaping area (18) are sequentially arranged along the fiber traction direction; The rear-mounted resin coating area is sealed and serves as an independent cavity for fiber resin impregnation. The interior of the rear-mounted resin coating area is filled with resin, and both ends of the rear-mounted resin coating area are connected to the pre-forming area and the heat curing and shaping area (18), respectively.

2. The post-installed adhesive coating mold for composite pultruded profiles according to claim 1, characterized in that: The preforming area includes a first threading plate (1), the four corners of the first threading plate (1) are fixedly connected to the ends of the connecting rod (12), the other end of the connecting rod (12) is fixedly connected to the main fixing plate (17), and a guide shaft (19) is fixedly installed between the opposite surfaces of the center of the first threading plate (1) and the main fixing plate (17). It also includes a second threading plate (2) and a third threading plate (3). The second threading plate (2) and the third threading plate (3) are both fixedly connected to the connecting rod (12) by a fastener (11). The side of the third threading plate (3) away from the second threading plate (2) is connected to the yarn take-up ring (4).

3. The post-installed adhesive coating mold for composite pultruded profiles according to claim 2, characterized in that: The center of the second threading plate (2) and the third threading plate (3) is equipped with an inner guide hollow tube (20), and the inner guide hollow tube (20) located between the opposite surfaces of the first threading plate (1) and the second threading plate (2) is provided with an inner guide oblique opening, and an inner guide felter (10) is installed on the edge of the inner guide oblique opening. The inner guide hollow tube (20) is fitted on the outside of the guide shaft (19) and is coaxial with the guide shaft (19).

4. The post-installed adhesive coating mold for composite pultruded profiles according to claim 3, characterized in that: The rear-mounted adhesive application area includes a front mounting plate (5) and a rear mounting plate (8), and the four corners of the front mounting plate (5) and the rear mounting plate (8) are fixedly connected to the side wall of the connecting rod (12). A glue-applying cavity (13) is fixedly installed between the opposite surfaces of the front mounting plate (5) and the rear mounting plate (8). The side wall of the glue-applying cavity (13) is connected to the resin injection port (6), which is connected to an external resin supply system through a pipeline.

5. The post-installed adhesive coating mold for composite pultruded profiles according to claim 4, characterized in that: A front sealing ring (14) is installed on the front mounting plate (5), and a rear sealing ring (15) is installed on the rear mounting plate (8). The centers of the front sealing ring (14) and the rear sealing ring (15) are coaxial with the center of the guide shaft (19); It also includes a yarn support plate (7), which is located inside the glue-coating cavity (13) and is fixedly installed on the outside of the guide shaft (19). The yarn support plate (7) is coaxial with the guide shaft (19).

6. The post-installed adhesive coating mold for composite pultruded profiles according to claim 5, characterized in that: The other side of the main fixing plate (17) is fixedly connected to the heat curing and shaping area (18); An outer guide hollow tube (16) is installed on the main fixing plate (17). An outer guide oblique opening is provided at one end of the outer guide hollow tube (16) facing the rear mounting plate (8). An outer guide felt (9) is installed at the outer guide oblique opening. The outer guide hollow tube (16) is fitted on the outside of the guide shaft (19) and is coaxial with the guide shaft (19).

7. The post-installed adhesive coating mold for composite pultruded profiles according to claim 6, characterized in that: The outer guide bevel and the inner guide bevel are arranged in opposite directions.

8. A method for preparing a post-coating process for a composite pultruded profile, comprising a post-coating molding die for a composite pultruded profile according to any one of claims 1-7, characterized in that: Includes the following steps: Step 1, Fiber feeding: The carbon fiber, glass fiber or basalt fiber reinforced fiber bundle is drawn out from the yarn frame and fed into the preforming area of ​​the mold, passing through the first yarn threading plate, the second yarn threading plate and the third yarn threading plate in sequence. Step 2, Dry Pre-forming: The yarn-gathering loops in the pre-forming zone comb, organize, and gather the loose fiber bundles to complete the initial shape setting in the dry state; Step 3, Sealed Post-Layer Resin Coating: The pre-formed fiber bundles continuously enter the post-layer resin coating zone. The fiber bundles are loosely diffused by the internal yarn support plate and fully contact and wet the resin in the resin coating chamber. After wetting, they re-aggregate. At the same time, the external resin supply system replenishes and circulates the resin in the resin coating zone in real time. Step 4, Heating and Curing: The fiber composite after the resin coating is completed is sent out from the post-coating area and directly enters the heating and curing area, where the resin is cured and the profile is shaped in the high-temperature mold cavity. Step 5, Traction and Material Collection: The cured composite material profiles are continuously pulled out by the traction device to complete the continuous pultrusion production.

9. The method for preparing a composite pultruded profile by post-coating according to claim 8, characterized in that: The dry preforming process parameters in step two and the glue-impregnation process parameters in step three are adjusted independently of each other.

Images