One-piece braiding method and application of an F-shaped tube

Abstract

The present invention belongs to the technical field of three-dimensional braided composites, and relates to an integrated braiding method and application of an F-shaped tube. Using thermoplastic polyurethane as the matrix and glass fiber as the reinforcing material, yarns are made by melt spinning, and an F-shaped tube is prepared by using an integrated braiding technique. Subsequently, the F-shaped tube is made into an F-shaped tube joint by using a hot pressing process. The present invention eliminates the splicing and sewing gaps of the F-shaped tube, improves the overall stiffness and strength, and further enhances the corrosion resistance of the F-shaped tube joint by combining thermoplastic polyurethane with high-performance fibers as the braiding material.

Description

Technical Field

[0001] The present invention belongs to the technical field of three-dimensional braided composites, and particularly relates to an integrated braiding method and application of an F-shaped tube. Background Art

[0002] The three-dimensional braided composite material technology is a high-tech in the field of materials science. It braids yarns into a three-dimensional structure according to specific paths and rules, enabling the fibers to be interlocked and staggered in a network distribution in space. Compared with traditional laminated composite materials, three-dimensional braided composite materials have a highly integrated structure, fundamentally solving the delamination problem and enabling the formation of composite materials with specific mechanical properties and functions. Based on these advantages, the three-dimensional braided composite material technology has been widely applied in many fields such as aerospace, chemical engineering, and medical devices.

[0003] As an application example of the three-dimensional braided composite material technology in the chemical engineering field, F-shaped tube joints are widely used to connect pipelines for transporting corrosive media. However, under the existing technical conditions, the structural forming of F-shaped tube joints mainly relies on the splicing and stitching technology. The specific operation is to splice and stitch different parts of the woven fiber materials to form the final F-shaped structure. But this preparation technology has obvious defects. First, during the splicing and stitching process, weak points are easily formed at the joints of the fiber materials. These weak points damage the sealing structure of the F-shaped tube joint, resulting in the overall mechanical properties of the F-shaped tube joint being affected. Second, limited by the splicing and stitching process, it is difficult to maintain the same fiber volume fraction and structural uniformity in different parts, further affecting the performance stability of the F-shaped tube joint. In non-uniform soil layers and soft soil layers, due to uneven settlement of the pipeline, the interface is damaged or offset, and liquid leakage is likely to occur. In addition, the splicing and stitching process has low production efficiency and a long production cycle, making it difficult to meet the large-scale production requirements of the chemical industry for F-shaped tube joints. Although the existing technology has disclosed the integrated braiding technology for multi-tube, these technologies are mainly applicable to multi-tube with relatively simple structures such as Y-shaped tubes and X-shaped tubes. The structural characteristics such as the distribution and angle of the branch tubes of the F-shaped tube joint are significantly different from those of multi-tubes such as Y-shaped tubes and X-shaped tubes, resulting in the existing integrated braiding technology being unable to be directly used for the preparation of F-shaped tube joints.

[0004] Therefore, developing an integrated braiding method applicable to F-shaped tube joints has become the key to solving the above problems. Summary of the Invention

[0005] The purpose of the present invention is to solve the problems in the existing technology and provide an integrated braiding method and application of an F-shaped tube.

[0006] To achieve the above purpose, the present invention adopts the following technical solutions:

[0007] An integrated braiding method of an F-shaped tube, comprising the following steps:

[0008] (a)Vertically arrange the first cylindrical core mold, and control 2n first yarns to interweave from top to bottom on the surface of the first cylindrical core mold until the intersection point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

[0009] (b)After horizontally arranging the second cylindrical core mold, control the left end of the second cylindrical core mold to be smoothly connected to the lower end of the first cylindrical core mold through a bending core mold, and the diameter of the second cylindrical core mold is equal to the diameter of the first cylindrical core mold;

[0010] Then control 2n first yarns to interweave from top to bottom on the surface of the bending core mold. During this process, continuously rotate the bending core mold clockwise so that the first yarns evenly cover the bending core mold until the intersection point reaches the connection between the bending core mold and the second cylindrical core mold. At this time, the second cylindrical core mold is in a vertical state, with the end connected to the bending core mold on top and the other end on the bottom;

[0011] (c)The second cylindrical core mold is divided into upper and lower sections. Control 2n first yarns to interweave from top to bottom on the surface of the upper section of the second cylindrical core mold until the intersection point reaches the junction between the upper and lower sections of the second cylindrical core mold;

[0012] (d)After horizontally arranging the third cylindrical core mold, control the left end of the third cylindrical core mold to be connected to the top of the lower section of the second cylindrical core mold, and the diameter of the third cylindrical core mold is equal to the diameter of the second cylindrical core mold;

[0013] Divide 2n first yarns into two groups equally;

[0014] Add n second yarns;

[0015] Then control the first group of first yarns and n second yarns to interweave from top to bottom on the surface of the lower section of the second cylindrical core mold until the intersection point reaches the lower end of the second cylindrical core mold;

[0016] (e)Rotate the third cylindrical core mold clockwise by 90° so that the end connected to the second cylindrical core mold is on top and the other end is on the bottom;

[0017] Add n third yarns;

[0018] Then control the second group of first yarns and n third yarns to interweave from top to bottom on the surface of the third cylindrical core mold until the intersection point reaches the lower end of the third cylindrical core mold, thus obtaining the F-shaped tube.

[0019] As a preferred technical solution:

[0020] For an integrated weaving method of an F-shaped tube as described above, the bending core mold is connected to the first cylindrical core mold and the second cylindrical core mold by glue, and the third cylindrical core mold is connected to the second cylindrical core mold by glue.

[0021] An integrated weaving method of an F-shaped tube as described in any of the above. The first yarn, the second yarn, and the third yarn are all continuous glass fiber / thermoplastic polyurethane composite filaments (in the present invention, the composite filaments are directly used as yarns for weaving). The continuous glass fiber / thermoplastic polyurethane composite filaments are prepared by melt spinning of thermoplastic polyurethane and continuous glass fibers. In the present invention, continuous glass fibers are used as reinforcing materials and combined with thermoplastic polyurethane, which can improve the mechanical properties and corrosion resistance of thermoplastic polyurethane, etc.

[0022] An integrated weaving method of an F-shaped tube as described above. The diameter of the continuous glass fiber / thermoplastic polyurethane composite filaments is 0.5 - 0.8 mm, and the weight ratio of continuous glass fibers to thermoplastic polyurethane is 1:1 - 5.

[0023] An integrated weaving method of an F-shaped tube as described above. During the melt spinning process, thermoplastic polyurethane is added from the main feeding port of the twin-screw extruder, and continuous glass fibers are fed into the extrusion head of the twin-screw extruder. The temperature range of the twin-screw extruder is 160 - 220 °C.

[0024] An application of an integrated weaving method of an F-shaped tube as described in any of the above, used for preparing a corrosion-resistant integrally woven F-shaped tube joint composite material. The specific process is as follows: After the F-shaped tube is made, each core mold is retained. The F-shaped tube is placed in an outer mold and subjected to hot pressing treatment. After the hot pressing treatment is completed, the outer mold and each core mold are removed, and the corrosion-resistant integrally woven F-shaped tube joint composite material is obtained.

[0025] As a preferred technical solution:

[0026] For the application as described above, the temperature of the hot pressing treatment is 180 - 220 °C, the time is 2 - 5 min, and the pressure is 0.5 - 2 MPa.

[0027] For the application as described above, before placing the F-shaped tube in the outer mold, a release cloth is attached to the inner surface of the outer mold. This can apply a certain pressure to the F-shaped tube, expel excess gas, reduce internal voids, and improve the quality of the product.

[0028] For the application as described above, the corrosion-resistant integrally woven F-shaped tube joint composite material has excellent corrosion resistance to salt solutions, acid solutions, or alkali solutions.

[0029] Beneficial effects:

[0030] The present invention uses an integrated weaving method to make an F-shaped tube joint, reducing the number of parts in the joint part. There are no splicing and sewing gaps, improving the overall stiffness and strength of the F-shaped tube joint.

[0031] During the knitting process of the present invention, the fibers are distributed according to specific paths and rules, and the fiber volume fraction and structural uniformity of different parts of the F-shaped tube are effectively controlled, ensuring the consistency of the overall performance.

[0032] The present invention combines thermoplastic polyurethane and high-performance fibers as the knitting material, improving the corrosion resistance of the F-shaped tube joint.

[0033] The present invention adopts an integrated knitting method, simplifies the production process, reduces the splicing and sewing processes, greatly improves the production efficiency, shortens the production cycle, and can meet the large-scale production requirements. Brief Description of the Drawings

[0034] Figures 1 to 6 They are schematic diagrams of different stages in the process of preparing the F-shaped tube of the present invention in sequence;

[0035] Figure 7 It is a schematic diagram of the melt spinning process when preparing the yarn of the present invention;

[0036] Among them, 1 - thermoplastic polyurethane, 2 - continuous glass fiber. Detailed Embodiments

[0037] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0038] Embodiment 1

[0039] An integrated knitting method for an F-shaped tube, comprising the following steps:

[0040] (1) Material preparation:

[0041] The first cylindrical core mold, the second cylindrical core mold, the third cylindrical core mold, and the bending core mold;

[0042] The first yarn, the second yarn, and the third yarn: all are continuous glass fiber / thermoplastic polyurethane composite filaments with a diameter of 0.7 mm. The continuous glass fiber / thermoplastic polyurethane composite filament is prepared by melt spinning thermoplastic polyurethane and continuous glass fiber at a weight ratio of 1:1 at 180°C; as Figure 7 shown, during the melt spinning process, thermoplastic polyurethane 1 is added from the main feeding port of the twin-screw extruder, and continuous glass fiber 2 is fed from the extrusion head of the twin-screw extruder. The temperature range of the twin-screw extruder is 160 - 220°C;

[0043] (2) Knitting:

[0044] (2.1) As shown in Figure 1 , arrange the first cylindrical core mold vertically, and control 2n first yarns to interweave from top to bottom on the surface of the first cylindrical core mold until the intersection point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

[0045] (2.2) As shown in Figure 2 , after arranging the second cylindrical core mold horizontally, control the left end of the second cylindrical core mold to be smoothly connected to the lower end of the first cylindrical core mold through a bending core mold, and the diameter of the second cylindrical core mold is equal to the diameter of the first cylindrical core mold;

[0046] Then control 2n first yarns to interweave from top to bottom on the surface of the bending core mold. As shown in Figure 3 , continuously rotate the bending core mold clockwise during this process so that the first yarns evenly cover the bending core mold until the intersection point reaches the connection between the bending core mold and the second cylindrical core mold. At this time, the second cylindrical core mold is in a vertical state, with the end connected to the bending core mold on top and the other end on the bottom;

[0047] (2.3) As shown in Figure 4 , the second cylindrical core mold is divided into upper and lower sections. Control 2n first yarns to interweave from top to bottom on the surface of the upper section of the second cylindrical core mold until the intersection point reaches the junction between the upper and lower sections of the second cylindrical core mold;

[0048] (2.4) As shown in Figure 5 , after arranging the third cylindrical core mold horizontally, control the left end of the third cylindrical core mold to be connected to the top of the lower section of the second cylindrical core mold, and the diameter of the third cylindrical core mold is equal to the diameter of the second cylindrical core mold;

[0049] Divide 2n first yarns into two groups equally;

[0050] Add n second yarns;

[0051] Then control the first group of first yarns and n second yarns to interweave from top to bottom on the surface of the lower section of the second cylindrical core mold until the intersection point reaches the lower end of the second cylindrical core mold;

[0052] (2.5) As shown in Figure 6 , rotate the third cylindrical core mold clockwise by 90° so that the end connected to the second cylindrical core mold is on top and the other end is on the bottom;

[0053] Add n third yarns;

[0054] Then control the second group of first yarns and n third yarns to interweave from top to bottom on the surface of the third cylindrical core mold until the intersection point reaches the lower end of the third cylindrical core mold, thus obtaining the F-shaped tube;

[0055] In step (2), the bending mandrel is connected to both the first cylindrical mandrel and the second cylindrical mandrel by glue, and the third cylindrical mandrel is connected to the second cylindrical mandrel by glue.

[0056] A method for preparing a corrosion-resistant integrally woven F-shaped pipe joint composite material. After the F-shaped pipe is obtained by the above-mentioned weaving method, each mandrel is retained. First, a release cloth is attached to the inner surface of the outer mold, and then the F-shaped pipe is placed in the outer mold and subjected to hot pressing treatment (temperature: 180 °C, time: 5 min, pressure: 1 MPa). After the hot pressing treatment is completed, the outer mold and each mandrel are removed to obtain the corrosion-resistant integrally woven F-shaped pipe joint composite material.

[0057] After the finally obtained corrosion-resistant integrally woven F-shaped pipe joint composite material is immersed in a 10% mass fraction sodium chloride solution for 30 days, there is no obvious change in the appearance of the F-shaped pipe joint, indicating excellent chemical medium corrosion resistance.

[0058] Example 2

[0059] An integral weaving method for an F-shaped pipe, comprising the following steps:

[0060] (1) Material preparation:

[0061] The first cylindrical mandrel, the second cylindrical mandrel, the third cylindrical mandrel, the bending mandrel;

[0062] The first yarn, the second yarn, the third yarn: all are continuous glass fiber / thermoplastic polyurethane composite filaments with a diameter of 0.7 mm. The continuous glass fiber / thermoplastic polyurethane composite filament is prepared by melt spinning thermoplastic polyurethane and continuous glass fiber at a weight ratio of 1:2 at 185 °C. During the melt spinning process, thermoplastic polyurethane is added from the main feed port of the twin-screw extruder, and continuous glass fiber is fed into the extruder head of the twin-screw extruder. The temperature range of the twin-screw extruder is 160 - 220 °C;

[0063] (2) Weaving:

[0064] (2.1) Vertically arrange the first cylindrical mandrel, and control 2n first yarns to interweave from top to bottom on the surface of the first cylindrical mandrel until the intersection point reaches the lower end of the first cylindrical mandrel, where n is a positive integer;

[0065] (2.2) After horizontally arranging the second cylindrical mandrel, control its left end to be smoothly connected to the lower end of the first cylindrical mandrel through the bending mandrel. The diameter of the second cylindrical mandrel is equal to the diameter of the first cylindrical mandrel;

[0066] Then, control 2n first yarns to interlace from top to bottom on the surface of the curved mandrel. During this process, continuously rotate the curved mandrel clockwise so that the first yarns evenly cover the curved mandrel until the intersection point reaches the connection between the curved mandrel and the second cylindrical mandrel. At this time, the second cylindrical mandrel is in a vertical state, with the end connected to the curved mandrel at the top and the other end at the bottom.

[0067] (2.3)The second cylindrical mandrel is divided into upper and lower sections. Control 2n first yarns to interlace from top to bottom on the surface of the upper section of the second cylindrical mandrel until the intersection point reaches the junction between the upper and lower sections of the second cylindrical mandrel.

[0068] (2.4)After horizontally arranging the third cylindrical mandrel, control its left end to be connected to the top of the lower section of the second cylindrical mandrel. The diameter of the third cylindrical mandrel is equal to the diameter of the second cylindrical mandrel.

[0069] Divide the 2n first yarns into two equal groups.

[0070] Add n second yarns.

[0071] Then, control the first group of first yarns and n second yarns to interlace from top to bottom on the surface of the lower section of the second cylindrical mandrel until the intersection point reaches the lower end of the second cylindrical mandrel.

[0072] (2.5)Rotate the third cylindrical mandrel clockwise by 90° so that the end connected to the second cylindrical mandrel is at the top and the other end is at the bottom.

[0073] Add n third yarns.

[0074] Then, control the second group of first yarns and n third yarns to interlace from top to bottom on the surface of the third cylindrical mandrel until the intersection point reaches the lower end of the third cylindrical mandrel, thus obtaining the F-shaped tube.

[0075] In step (2), the curved mandrel is connected to both the first cylindrical mandrel and the second cylindrical mandrel by glue, and the third cylindrical mandrel is connected to the second cylindrical mandrel by glue.

[0076] A preparation method of a corrosion-resistant integrally woven F-shaped tube joint composite material. After obtaining the F-shaped tube by the above weaving method, retain each mandrel. First, attach a release cloth to the inner surface of the outer mold, then place the F-shaped tube in the outer mold and perform a hot pressing treatment on it (temperature: 185 °C, time: 2 min, pressure: 0.8 MPa). After the hot pressing treatment is completed, remove the outer mold and each mandrel, thus obtaining the corrosion-resistant integrally woven F-shaped tube joint composite material.

[0077] After the finally obtained corrosion-resistant integrally woven F-shaped tube joint composite material is immersed in a 10% sodium chloride solution by mass fraction for 30 days, the appearance of the F-shaped tube joint does not change significantly, and it has excellent chemical medium corrosion resistance.

[0078] Example 3

[0079] An integrated braiding method for an F-shaped tube, comprising the following steps:

[0080] (1) Material preparation:

[0081] The first cylindrical core mold, the second cylindrical core mold, the third cylindrical core mold, and the bending core mold;

[0082] The first yarn, the second yarn, and the third yarn: all are continuous glass fiber / thermoplastic polyurethane composite filaments with a diameter of 0.7 mm. The continuous glass fiber / thermoplastic polyurethane composite filament is prepared by melt spinning thermoplastic polyurethane and continuous glass fiber at a weight ratio of 1:3 at 190 °C; during the melt spinning process, thermoplastic polyurethane is added from the main feeding port of the twin-screw extruder, and continuous glass fiber is fed into the extrusion head of the twin-screw extruder. The temperature range of the twin-screw extruder is 160 - 220 °C;

[0083] (2) Braiding:

[0084] (2.1) Vertically arrange the first cylindrical core mold, and control 2n first yarns to interweave from top to bottom on the surface of the first cylindrical core mold until the intersection point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

[0085] After horizontally arranging the second cylindrical core mold, control the left end of it to be smoothly connected to the lower end of the first cylindrical core mold through the bending core mold. The diameter of the second cylindrical core mold is equal to the diameter of the first cylindrical core mold;

[0086] Then control 2n first yarns to interweave from top to bottom on the surface of the bending core mold. During this process, continuously rotate the bending core mold clockwise so that the first yarns evenly cover the bending core mold until the intersection point reaches the connection between the bending core mold and the second cylindrical core mold. At this time, the second cylindrical core mold is in a vertical state, with the end connected to the bending core mold on top and the other end on the bottom;

[0087] The second cylindrical core mold is divided into upper and lower sections. Control 2n first yarns to interweave from top to bottom on the upper section surface of the second cylindrical core mold until the intersection point reaches the junction between the upper and lower sections of the second cylindrical core mold;

[0088] After horizontally arranging the third cylindrical core mold, control the left end of it to be connected to the top of the lower section of the second cylindrical core mold. The diameter of the third cylindrical core mold is equal to the diameter of the second cylindrical core mold;

[0089] Divide 2n first yarns into two equal groups;

[0090] Add n new second yarns;

[0091] Then control the first yarn of the first group and n second yarns to interlace from top to bottom on the lower surface of the second cylindrical mandrel until the intersection point reaches the lower end of the second cylindrical mandrel;

[0092] (2.5) Rotate the third cylindrical mandrel clockwise by 90° so that the end connected to the second cylindrical mandrel is on the top and the other end is on the bottom;

[0093] Add n third yarns;

[0094] Then control the first yarn of the second group and n third yarns to interlace from top to bottom on the surface of the third cylindrical mandrel until the intersection point reaches the lower end of the third cylindrical mandrel, thus obtaining the F-shaped tube;

[0095] In step (2), the bending mandrel is connected to both the first cylindrical mandrel and the second cylindrical mandrel by glue, and the third cylindrical mandrel is connected to the second cylindrical mandrel by glue.

[0096] A preparation method of a corrosion-resistant integrally woven F-shaped tube joint composite material. After the F-shaped tube is obtained by the above weaving method, each mandrel is retained; first, a release cloth is attached to the inner surface of the outer mold, then the F-shaped tube is placed in the outer mold and subjected to hot pressing treatment (temperature: 190 °C, time: 4 min, pressure: 0.6 MPa). After the hot pressing treatment is completed, the outer mold and each mandrel are removed, thus obtaining the corrosion-resistant integrally woven F-shaped tube joint composite material.

[0097] After the finally obtained corrosion-resistant integrally woven F-shaped tube joint composite material is immersed in a 10% sulfuric acid solution by mass fraction for 30 days, the appearance of the F-shaped tube joint has no obvious change, and it has excellent chemical medium corrosion resistance.

[0098] Example 4

[0099] An integral weaving method of an F-shaped tube, comprising the following steps:

[0100] (1) Material preparation:

[0101] The first cylindrical mandrel, the second cylindrical mandrel, the third cylindrical mandrel, the bending mandrel;

[0102] The first yarn, the second yarn, the third yarn: all are continuous glass fiber / thermoplastic polyurethane composite filaments with a diameter of 0.6 mm. The continuous glass fiber / thermoplastic polyurethane composite filaments are prepared by melt spinning at 195 °C with a weight ratio of thermoplastic polyurethane to continuous glass fiber of 1:4; during the melt spinning process, the thermoplastic polyurethane is added from the main feeding port of the twin-screw extruder, and the continuous glass fiber is fed from the extrusion head of the twin-screw extruder. The temperature range of the twin-screw extruder is 160 - 220 °C;

[0103] (2) Weaving:

[0104] (2.1)Vertically arrange the first cylindrical core mold, and control 2n first yarns to interweave from top to bottom on the surface of the first cylindrical core mold until the intersection point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

[0105] (2.2)After horizontally arranging the second cylindrical core mold, control its left end to be smoothly connected to the lower end of the first cylindrical core mold through a bending core mold. The diameter of the second cylindrical core mold is equal to that of the first cylindrical core mold;

[0106] Then control 2n first yarns to interweave from top to bottom on the surface of the bending core mold. During this process, continuously rotate the bending core mold clockwise so that the first yarns evenly cover the bending core mold until the intersection point reaches the connection between the bending core mold and the second cylindrical core mold. At this time, the second cylindrical core mold is in a vertical state, with the end connected to the bending core mold on top and the other end on the bottom;

[0107] (2.3)The second cylindrical core mold is divided into upper and lower sections. Control 2n first yarns to interweave from top to bottom on the surface of the upper section of the second cylindrical core mold until the intersection point reaches the junction between the upper and lower sections of the second cylindrical core mold;

[0108] (2.4)After horizontally arranging the third cylindrical core mold, control its left end to be connected to the top of the lower section of the second cylindrical core mold. The diameter of the third cylindrical core mold is equal to that of the second cylindrical core mold;

[0109] Divide 2n first yarns into two groups equally;

[0110] Add n second yarns;

[0111] Then control the first group of first yarns and n second yarns to interweave from top to bottom on the surface of the lower section of the second cylindrical core mold until the intersection point reaches the lower end of the second cylindrical core mold;

[0112] (2.5)Rotate the third cylindrical core mold clockwise by 90° so that the end connected to the second cylindrical core mold is on top and the other end is on the bottom;

[0113] Add n third yarns;

[0114] Then control the second group of first yarns and n third yarns to interweave from top to bottom on the surface of the third cylindrical core mold until the intersection point reaches the lower end of the third cylindrical core mold, thus obtaining the F-shaped tube;

[0115] In step (2), the bending core mold is connected to both the first cylindrical core mold and the second cylindrical core mold by glue, and the third cylindrical core mold is connected to the second cylindrical core mold by glue.

[0116] A method for preparing a corrosion-resistant integrally woven F-shaped pipe joint composite material. After the F-shaped pipe is obtained by the above weaving method, each core mold is retained. First, a release cloth is attached to the inner surface of the outer mold, and then the F-shaped pipe is placed in the outer mold and subjected to hot pressing treatment (temperature: 195 °C, time: 3 min, pressure: 0.5 MPa). After the hot pressing treatment is completed, the outer mold and each core mold are removed, and the corrosion-resistant integrally woven F-shaped pipe joint composite material is obtained.

[0117] After the finally obtained corrosion-resistant integrally woven F-shaped pipe joint composite material is immersed in a sulfuric acid solution with a mass fraction of 10% for 30 days, the appearance of the F-shaped pipe joint has no obvious change, and it has excellent corrosion resistance to chemical media.

[0118] Example 5

[0119] An integral weaving method for an F-shaped pipe, comprising the following steps:

[0120] (1) Material preparation:

[0121] The first cylindrical core mold, the second cylindrical core mold, the third cylindrical core mold, and the bending core mold;

[0122] The first yarn, the second yarn, and the third yarn: all are continuous glass fiber / thermoplastic polyurethane composite filaments with a diameter of 0.5 mm. The continuous glass fiber / thermoplastic polyurethane composite filaments are prepared by melt spinning at 200 °C with a weight ratio of thermoplastic polyurethane to continuous glass fiber of 1:5. During the melt spinning process, the thermoplastic polyurethane is added from the main feeding port of the twin-screw extruder, and the continuous glass fiber is fed from the extrusion head of the twin-screw extruder. The temperature range of the twin-screw extruder is 160 - 220 °C;

[0123] (2) Weaving:

[0124] (2.1) Vertically arrange the first cylindrical core mold, and control 2n first yarns to interweave from top to bottom on the surface of the first cylindrical core mold until the intersection point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

[0125] After horizontally arranging the second cylindrical core mold, control the left end of the second cylindrical core mold to be smoothly connected to the lower end of the first cylindrical core mold through the bending core mold. The diameter of the second cylindrical core mold is equal to the diameter of the first cylindrical core mold;

[0126] Then control 2n first yarns to interweave from top to bottom on the surface of the bending core mold. During this process, continuously rotate the bending core mold clockwise so that the first yarns evenly cover the bending core mold until the intersection point reaches the connection between the bending core mold and the second cylindrical core mold. At this time, the second cylindrical core mold is in a vertical state, with the end connected to the bending core mold at the top and the other end at the bottom;

[0127] (2.3)The second cylindrical core mold is divided into upper and lower sections. Control 2n first yarns to interweave from top to bottom on the surface of the upper section of the second cylindrical core mold until the intersection point reaches the junction of the upper and lower sections of the second cylindrical core mold;

[0128] (2.4)After horizontally arranging the third cylindrical core mold, control the connection of its left end to the top of the lower section of the second cylindrical core mold. The diameter of the third cylindrical core mold is equal to the diameter of the second cylindrical core mold;

[0129] Divide the 2n first yarns into two equal groups;

[0130] Add n second yarns;

[0131] Then control the first group of first yarns and n second yarns to interweave from top to bottom on the surface of the lower section of the second cylindrical core mold until the intersection point reaches the lower end of the second cylindrical core mold;

[0132] (2.5)Rotate the third cylindrical core mold clockwise by 90° so that the end connected to the second cylindrical core mold is on the upper side and the other end is on the lower side;

[0133] Add n third yarns;

[0134] Then control the second group of first yarns and n third yarns to interweave from top to bottom on the surface of the third cylindrical core mold until the intersection point reaches the lower end of the third cylindrical core mold, thus obtaining the F-shaped tube;

[0135] In step (2), the bending core mold is connected to both the first cylindrical core mold and the second cylindrical core mold by glue, and the third cylindrical core mold is connected to the second cylindrical core mold by glue.

[0136] A preparation method of a corrosion-resistant integrally woven F-shaped tube joint composite material. After obtaining the F-shaped tube by the above weaving method, retain each core mold; first attach a release cloth to the inner surface of the outer mold, then place the F-shaped tube in the outer mold and perform hot pressing treatment on it (temperature is 200 °C, time is 5 min, pressure is 1 MPa). After the hot pressing treatment is completed, remove the outer mold and each core mold, thus obtaining the corrosion-resistant integrally woven F-shaped tube joint composite material.

[0137] After the finally obtained corrosion-resistant integrally woven F-shaped tube joint composite material is immersed in a 10% mass fraction sodium hydroxide solution for 30 days, the appearance of the F-shaped tube joint has no obvious change, and it has excellent chemical medium corrosion resistance.

[0138] Example 6

[0139] An integral weaving method of an F-shaped tube, comprising the following steps:

[0140] (1)Material preparation:

[0141] The first cylindrical core mold, the second cylindrical core mold, the third cylindrical core mold, and the bending core mold;

[0142] The first yarn, the second yarn, and the third yarn: all are continuous glass fiber / thermoplastic polyurethane composite filaments with a diameter of 0.8 mm. The continuous glass fiber / thermoplastic polyurethane composite filament is prepared by melt spinning at 205 °C with a weight ratio of thermoplastic polyurethane to continuous glass fiber of 1:2. During the melt spinning process, the thermoplastic polyurethane is added from the main feeding port of the twin-screw extruder, and the continuous glass fiber is fed into the extrusion head of the twin-screw extruder. The temperature range of the twin-screw extruder is 160 - 220 °C;

[0143] (2) Weaving:

[0144] (2.1) Vertically arrange the first cylindrical core mold, and control 2n first yarns to interweave from top to bottom on the surface of the first cylindrical core mold until the intersection point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

[0145] (2.2) After horizontally arranging the second cylindrical core mold, control the left end of it to be smoothly connected to the lower end of the first cylindrical core mold through the bending core mold. The diameter of the second cylindrical core mold is equal to the diameter of the first cylindrical core mold;

[0146] Then control 2n first yarns to interweave from top to bottom on the surface of the bending core mold. During this process, continuously rotate the bending core mold clockwise so that the first yarns evenly cover the bending core mold until the intersection point reaches the connection between the bending core mold and the second cylindrical core mold. At this time, the second cylindrical core mold is in a vertical state, with the end connected to the bending core mold on top and the other end at the bottom;

[0147] (2.3) The second cylindrical core mold is divided into upper and lower sections. Control 2n first yarns to interweave from top to bottom on the upper section surface of the second cylindrical core mold until the intersection point reaches the junction between the upper and lower sections of the second cylindrical core mold;

[0148] (2.4) After horizontally arranging the third cylindrical core mold, control the left end of it to be connected to the top of the lower section of the second cylindrical core mold. The diameter of the third cylindrical core mold is equal to the diameter of the second cylindrical core mold;

[0149] Divide 2n first yarns into two equal groups;

[0150] Add n second yarns;

[0151] Then control the first group of first yarns and n second yarns to interweave from top to bottom on the lower section surface of the second cylindrical core mold until the intersection point reaches the lower end of the second cylindrical core mold;

[0152] (2.5) Rotate the third cylindrical core mold clockwise by 90°, so that the end connected to the second cylindrical core mold is on top and the other end is at the bottom;

[0153] Add n third yarns;

[0154] Then control the second group of first yarns and n third yarns to interweave from top to bottom on the surface of the third cylindrical core mold until the intersection point reaches the lower end of the third cylindrical core mold, thus obtaining the F-shaped tube;

[0155] In step (2), the bending core mold is connected to both the first cylindrical core mold and the second cylindrical core mold by glue, and the third cylindrical core mold is connected to the second cylindrical core mold by glue.

[0156] A preparation method of a corrosion-resistant integrally woven F-shaped tube joint composite material. After the F-shaped tube is obtained by the above weaving method, each core mold is retained; first, a release cloth is attached to the inner surface of the outer mold, then the F-shaped tube is placed in the outer mold and subjected to hot pressing treatment (temperature: 205°C, time: 5 min, pressure: 1.5 MPa). After the hot pressing treatment is completed, the outer mold and each core mold are removed, thus obtaining the corrosion-resistant integrally woven F-shaped tube joint composite material.

[0157] After the finally obtained corrosion-resistant integrally woven F-shaped tube joint composite material is immersed in a 10% sodium hydroxide solution by mass fraction for 30 days, the appearance of the F-shaped tube joint has no obvious change, and it has excellent corrosion resistance to chemical media.

Claims

1. An integrated braiding method for an F-shaped tube, characterized in that, It includes the following steps: (a) Vertically arrange the first cylindrical core mold, and control 2n first yarns to interweave from top to bottom on the surface of the first cylindrical core mold until the intersection point reaches the lower end of the first cylindrical core mold, where n is a positive integer; (b) After horizontally arranging the second cylindrical core mold, control the left end of it to be smoothly connected with the lower end of the first cylindrical core mold through a bending core mold. The diameter of the second cylindrical core mold is equal to that of the first cylindrical core mold; Then control 2n first yarns to interweave from top to bottom on the surface of the bending core mold. During this process, continuously rotate the bending core mold clockwise so that the first yarns evenly cover the bending core mold until the intersection point reaches the connection between the bending core mold and the second cylindrical core mold. At this time, the second cylindrical core mold is in a vertical state, with the end connected to the bending core mold on the upper side and the other end on the lower side; (c) The second cylindrical core mold is divided into upper and lower sections. Control 2n first yarns to interweave from top to bottom on the surface of the upper section of the second cylindrical core mold until the intersection point reaches the junction between the upper and lower sections of the second cylindrical core mold; (d) After horizontally arranging the third cylindrical core mold, control the left end of it to be connected to the top of the lower section of the second cylindrical core mold. The diameter of the third cylindrical core mold is equal to that of the second cylindrical core mold; Divide 2n first yarns into two groups equally; Add n second yarns; Then control the first group of first yarns and n second yarns to interweave from top to bottom on the surface of the lower section of the second cylindrical core mold until the intersection point reaches the lower end of the second cylindrical core mold; (e) Rotate the third cylindrical core mold clockwise by 90° so that the end connected to the second cylindrical core mold is on the upper side and the other end is on the lower side; Add n third yarns; Then control the second group of first yarns and n third yarns to interweave from top to bottom on the surface of the third cylindrical core mold until the intersection point reaches the lower end of the third cylindrical core mold, thus obtaining the F-shaped tube; The first yarn, the second yarn, and the third yarn are all continuous glass fiber / thermoplastic polyurethane composite filaments, and the continuous glass fiber / thermoplastic polyurethane composite filaments are prepared by melt spinning of thermoplastic polyurethane and continuous glass fiber.

2. The one-piece braiding method of an F-shaped tube according to claim 1, characterized in that The bending core mold is connected to the first cylindrical core mold and the second cylindrical core mold by glue, and the third cylindrical core mold is connected to the second cylindrical core mold by glue.

3. The integrated braiding method of an F-shaped tube according to claim 1, wherein, The diameter of the continuous glass fiber / thermoplastic polyurethane composite filament is 0.5 - 0.8 mm, and the weight ratio of continuous glass fiber to thermoplastic polyurethane is 1:1 - 5.

4. The integrated braiding method of an F-shaped tube according to claim 1, characterized in that, During the melt spinning process, thermoplastic polyurethane is added from the main feeding port of the twin-screw extruder, and continuous glass fiber is fed from the extrusion head of the twin-screw extruder. The temperature range of the twin-screw extruder is 160 - 220 °C.

5. Application of an integrated braiding method for an F-shaped tube according to any one of claims 3 to 4, characterized in that, It is used for preparing the corrosion-resistant integral braided F-shaped tube joint composite material. The specific process is as follows: after obtaining the F-shaped tube, retain each core mold, place the F-shaped tube in the outer mold and conduct hot pressing treatment on it. After the hot pressing treatment is completed, remove the outer mold and each core mold, thus obtaining the corrosion-resistant integral braided F-shaped tube joint composite material.

6. The application according to claim 5, wherein The temperature of the hot pressing treatment is 180 - 220 °C, the time is 2 - 5 min, and the pressure is 0.5 - 2 MPa.

7. The application according to claim 5, characterized in that, Before placing the F-shaped tube in the outer mold, attach a release cloth to the inner surface of the outer mold.

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