Integrated weaving method and application of F-shaped pipe

Abstract

The invention belongs to the technical field of three-dimensional woven composite materials, and relates to an integrated weaving method and application of an F-shaped pipe, thermoplastic polyurethane is adopted as a matrix, glass fiber is adopted as a reinforcing material, yarns are prepared through melt spinning, the F-shaped pipe is prepared through the integrated weaving technology, and then the F-shaped pipe is made into an F-shaped pipe joint through the hot pressing technology. According to the F-shaped pipe joint, splicing and sewing gaps of the F-shaped pipe are eliminated, the overall rigidity and strength are improved, thermoplastic polyurethane and high-performance fibers are combined into a weaving material, and the corrosion resistance of the F-shaped pipe joint is further enhanced.

Description

Technical Field

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

[0002] Three-dimensional braided composite material technology is a high-tech in the field of materials science. It weaves yarns into a three-dimensional structure according to specific paths and rules, allowing the fibers to be interlocked and distributed in space in a mesh-like manner. Compared with traditional laminated composite materials, three-dimensional braided composite materials have a highly integrated structure, which fundamentally solves the stratification problem and forms composite materials with specific mechanical properties and functions. Based on these advantages, three-dimensional braided composite material technology has been widely used in aerospace, chemical industry, medical equipment and other fields.

[0003] As an application example of three-dimensional braided composite material technology in the chemical industry, the F-shaped pipe joint is widely used to connect pipes that transport corrosive media. However, under the existing technical conditions, the structural forming of the F-shaped pipe joint mainly relies on the splicing and suturing technology. The specific operation is to splice and sew the woven fiber materials of different parts to form the final F-shaped structure. However, this preparation technology has obvious defects. First, during the splicing and suturing process, weak points are easily formed at the joints of the fiber materials. These weak points destroy the sealing structure of the F-shaped pipe joint, resulting in the overall mechanical properties of the F-shaped pipe joint being affected; secondly, due to the limitations of the splicing and suturing process, the fiber volume fraction and structural uniformity of different parts are difficult to maintain consistency, which further affects the performance stability of the F-shaped pipe joint. In uneven soil layers and soft soil layers, the interface is damaged or offset due to uneven settlement of the pipeline, and leakage is prone to occur; in addition, the splicing and suturing process has low production efficiency and a long production cycle, which is difficult to meet the needs of the chemical industry for large-scale production of F-shaped pipe joints. Although the prior art has disclosed the integrated braiding technology of multi-way pipes, these technologies are mainly applicable to multi-way pipes with relatively simple structures such as Y-shaped pipes and X-shaped pipes. The structural characteristics of the F-shaped pipe joint, such as the distribution and angle of branch pipes, are significantly different from those of multi-way pipes such as Y-shaped pipes and X-shaped pipes, resulting in the inability of the existing one-piece braiding technology to be directly used for the preparation of F-shaped pipe joints.

[0004] Therefore, developing an integrated braiding method suitable for F-shaped pipe joints becomes 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 prior art and to provide an integrated braiding method and application of an F-shaped tube.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme:

[0007] An integrated braiding method for an F-shaped tube comprises the following steps:

[0008] (a) arranging the first cylindrical core mold vertically, controlling 2n first yarns to be interwoven from top to bottom on the surface of the first cylindrical core mold until the interweaving point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

[0009] (b) After the second cylindrical core mold is arranged horizontally, its left end is controlled to be smoothly connected with the lower end of the first cylindrical core mold through the 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, 2n first yarns are controlled to be interwoven from top to bottom on the surface of the bending core mold, and the bending core mold is continuously rotated clockwise during this process, so that the first yarns evenly cover the bending core mold until the interwoven point reaches the connection between the bending core mold and the second cylindrical core mold, at which time the second cylindrical core mold is in a vertical state, with one end connected to the bending core mold at the top and the other end at the bottom;

[0011] (c) the second cylindrical core mold is divided into two sections, the upper and lower sections, and the 2n first yarns are controlled to be interwoven from top to bottom on the surface of the upper section of the second cylindrical core mold until the interwoven point reaches the junction of the upper section and the lower section of the second cylindrical core mold;

[0012] (d) after arranging the third cylindrical core mold horizontally, control the left end thereof 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 equal groups;

[0014] Add n second yarns;

[0015] Then, the first group of first yarns and n second yarns are controlled to be interwoven from top to bottom on the lower surface of the second cylindrical core mold until the interwoven point reaches the lower end of the second cylindrical core mold;

[0016] (e) rotating the third cylindrical core mold 90° clockwise so that one end thereof connected to the second cylindrical core mold is at the top and the other end thereof is at the bottom;

[0017] Add n third yarns;

[0018] Then, the second group of first yarns and n third yarns are controlled to be interwoven from top to bottom on the surface of the third cylindrical core mold until the interwoven point reaches the lower end of the third cylindrical core mold, thereby obtaining an F-shaped tube.

[0019] As the preferred technical solution:

[0020] In the integrated braiding 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] In an integrated weaving method for an F-shaped tube as described in any of the above items, the first yarn, the second yarn and the third yarn are all continuous glass fiber / thermoplastic polyurethane composite filaments (the present invention directly weaves the composite filaments as yarns), and the continuous glass fiber / thermoplastic polyurethane composite filaments are obtained by melt spinning thermoplastic polyurethane and continuous glass fiber. The present invention uses continuous glass fiber as a reinforcing material and combines it with thermoplastic polyurethane to improve the mechanical properties and corrosion resistance of thermoplastic polyurethane.

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

[0023] In the one-piece braiding method of an F-shaped tube as described above, during the melt spinning process, thermoplastic polyurethane is added from the main feed port of a twin-screw extruder, and continuous glass fiber is fed from the extrusion head of the twin-screw extruder, and the temperature range of the twin-screw extruder is 160-220°C.

[0024] The application of an integrated braiding method for an F-shaped tube as described in any of the above items is used to prepare a corrosion-resistant integrally braided F-shaped pipe joint composite material. The specific process is: after the F-shaped tube is obtained, each core mold is retained, the F-shaped tube is placed in an outer mold and subjected to a hot pressing treatment. After the hot pressing treatment is completed, the outer mold and each core mold are removed to obtain a corrosion-resistant integrally braided F-shaped pipe joint composite material.

[0025] As the preferred technical solution:

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

[0027] 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, which can give the F-shaped tube a certain pressure, remove excess gas, reduce internal voids, and improve product quality.

[0028] As described above, the corrosion-resistant integral braided F-shaped pipe joint composite material has excellent corrosion resistance to salt solution, acid solution or alkali solution.

[0029] Beneficial effects:

[0030] The present invention adopts an integrated weaving method to manufacture the F-shaped pipe joint, which reduces the number of parts of the joint, eliminates the splicing and suturing gaps, and improves the overall rigidity and strength of the F-shaped pipe joint.

[0031] During the weaving 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, thereby ensuring the consistency of the overall performance.

[0032] The present invention combines thermoplastic polyurethane with high-performance fibers as a braiding material, thereby improving the corrosion resistance of the F-shaped pipe joint.

[0033] The present invention adopts an integrated weaving method, simplifies the production process, reduces the splicing and sewing processes, greatly improves production efficiency, shortens the production cycle, and can meet large-scale production needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 to Figure 6 The schematic diagrams of different stages in the process of preparing an F-shaped tube according to the present invention are shown in sequence;

[0035] Figure 7 A schematic diagram of the melt spinning process for preparing yarns according to the present invention;

[0036] Among them, 1-thermoplastic polyurethane, 2-continuous glass fiber. DETAILED DESCRIPTION

[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 are not intended 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 fall within the scope limited by the appended claims of the application equally.

[0038] Example 1

[0039] An integrated braiding method for an F-shaped tube comprises the following steps:

[0040] (1) Material preparation:

[0041] A first cylindrical core mold, a second cylindrical core mold, a third cylindrical core mold, and a bending core mold;

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

[0043] (2) Weaving:

[0044] (2.1) If Figure 1 As shown, the first cylindrical core mold is arranged vertically, and 2n first yarns are controlled to be interwoven from top to bottom on the surface of the first cylindrical core mold until the interwoven point reaches the lower end of the first cylindrical core mold, and n is a positive integer;

[0045] (2.2) If Figure 2 As shown, after the second cylindrical core mold is arranged horizontally, its left end is controlled to be smoothly connected with the lower end of the first cylindrical core mold through a bent core mold, and the diameter of the second cylindrical core mold is equal to the diameter of the first cylindrical core mold;

[0046] Then, 2n first yarns are controlled to be interwoven from top to bottom on the surface of the bending mandrel, such as Figure 3 As shown, during this process, the bending core mold is continuously rotated clockwise so that the first yarn evenly covers the bending core mold until the interlacing 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 one end connected to the bending core mold at the top and the other end at the bottom;

[0047] (2.3) If Figure 4 As shown, the second cylindrical core mold is divided into two sections, the upper and lower sections, and the 2n first yarns are controlled to be interwoven from top to bottom on the upper section surface of the second cylindrical core mold until the interwoven point reaches the junction of the upper section and the lower section of the second cylindrical core mold;

[0048] (2.4) If Figure 5 As shown, after the third cylindrical core mold is arranged horizontally, its left end is controlled 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 equal groups;

[0050] Add n second yarns;

[0051] Then, the first group of first yarns and n second yarns are controlled to be interwoven from top to bottom on the lower surface of the second cylindrical core mold until the interwoven point reaches the lower end of the second cylindrical core mold;

[0052] (2.5) If Figure 6 As shown, the third cylindrical core mold is rotated 90° clockwise so that one end connected to the second cylindrical core mold is at the top and the other end is at the bottom;

[0053] Add n third yarns;

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

[0055] In step (2), 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.

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

[0057] After the corrosion-resistant integral braided F-shaped pipe joint composite material was immersed in a 10% by mass sodium chloride solution for 30 days, there was no obvious change in the appearance of the F-shaped pipe joint, and the F-shaped pipe joint had excellent resistance to chemical medium corrosion.

[0058] Example 2

[0059] An integrated braiding method for an F-shaped tube comprises the following steps:

[0060] (1) Material preparation:

[0061] A first cylindrical core mold, a second cylindrical core mold, a third cylindrical core mold, and a bending core mold;

[0062] The first yarn, the second yarn, and the third yarn are all continuous glass fiber / thermoplastic polyurethane composite filaments with a diameter of 0.7 mm, and the continuous glass fiber / thermoplastic polyurethane composite filaments are 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 feeding port of a twin-screw extruder, and continuous glass fiber is fed from the extrusion head of the twin-screw extruder, and the temperature range of the twin-screw extruder is 160-220° C.;

[0063] (2) Weaving:

[0064] (2.1) The first cylindrical core mold is arranged vertically, and 2n first yarns are controlled to be interwoven from top to bottom on the surface of the first cylindrical core mold until the interwoven point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

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

[0066] Then, 2n first yarns are controlled to be interwoven from top to bottom on the surface of the bending core mold, and the bending core mold is continuously rotated clockwise during this process, so that the first yarns evenly cover the bending core mold until the interwoven point reaches the connection between the bending core mold and the second cylindrical core mold, at which time the second cylindrical core mold is in a vertical state, with one end connected to the bending core mold at the top and the other end at the bottom;

[0067] (2.3) The second cylindrical core mold is divided into two sections, an upper section and an lower section, and the 2n first yarns are controlled to be interwoven from top to bottom on the surface of the upper section of the second cylindrical core mold until the interwoven point reaches the junction of the upper section and the lower section of the second cylindrical core mold;

[0068] (2.4) After arranging the third cylindrical core mold horizontally, control its left end 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;

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

[0070] Add n second yarns;

[0071] Then, the first group of first yarns and n second yarns are controlled to be interwoven from top to bottom on the lower surface of the second cylindrical core mold until the interwoven point reaches the lower end of the second cylindrical core mold;

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

[0073] Add n third yarns;

[0074] Then, the second group of first yarns and n third yarns are controlled to be interwoven from top to bottom on the surface of the third cylindrical core mold until the interwoven point reaches the lower end of the third cylindrical core mold, thus obtaining an F-shaped tube;

[0075] In step (2), 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.

[0076] A method for preparing a corrosion-resistant integrally braided F-shaped pipe joint composite material. After the F-shaped pipe is prepared by the above-mentioned braiding method, each core mold is retained; a release cloth is first attached to the inner surface of an outer mold, and then the F-shaped pipe is placed in the outer mold and subjected to a hot pressing treatment (temperature of 185°C, time of 2 minutes, pressure of 0.8MPa). After the hot pressing treatment is completed, the outer mold and each core mold are removed to obtain a corrosion-resistant integrally braided F-shaped pipe joint composite material.

[0077] After the corrosion-resistant integral braided F-shaped pipe joint composite material was immersed in a 10% by mass sodium chloride solution for 30 days, there was no obvious change in the appearance of the F-shaped pipe joint, and the F-shaped pipe joint had excellent resistance to chemical medium corrosion.

[0078] Example 3

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

[0080] (1) Material preparation:

[0081] A first cylindrical core mold, a second cylindrical core mold, a third cylindrical core mold, and a bending core mold;

[0082] The first yarn, the second yarn, and the third yarn are all continuous glass fiber / thermoplastic polyurethane composite filaments with a diameter of 0.7 mm, and the continuous glass fiber / thermoplastic polyurethane composite filaments are 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 a twin-screw extruder, and continuous glass fiber is fed from the extrusion head of the twin-screw extruder, and the temperature range of the twin-screw extruder is 160-220° C.;

[0083] (2) Weaving:

[0084] (2.1) The first cylindrical core mold is arranged vertically, and 2n first yarns are controlled to be interwoven from top to bottom on the surface of the first cylindrical core mold until the interwoven point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

[0085] (2.2) After arranging the second cylindrical core mold horizontally, control its left end to be smoothly connected with the lower end of the first cylindrical core mold through the bending core mold, and the diameter of the second cylindrical core mold is equal to the diameter of the first cylindrical core mold;

[0086] Then, 2n first yarns are controlled to be interwoven from top to bottom on the surface of the bending core mold, and the bending core mold is continuously rotated clockwise during this process, so that the first yarns evenly cover the bending core mold until the interwoven point reaches the connection between the bending core mold and the second cylindrical core mold, at which time the second cylindrical core mold is in a vertical state, with one end connected to the bending core mold at the top and the other end at the bottom;

[0087] (2.3) The second cylindrical core mold is divided into two sections, an upper section and an lower section, and the 2n first yarns are controlled to be interwoven from top to bottom on the surface of the upper section of the second cylindrical core mold until the interwoven point reaches the junction of the upper section and the lower section of the second cylindrical core mold;

[0088] (2.4) After arranging the third cylindrical core mold horizontally, control its left end 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;

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

[0090] Add n second yarns;

[0091] Then, the first group of first yarns and n second yarns are controlled to be interwoven from top to bottom on the lower surface of the second cylindrical core mold until the interwoven point reaches the lower end of the second cylindrical core mold;

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

[0093] Add n third yarns;

[0094] Then, the second group of first yarns and n third yarns are controlled to be interwoven from top to bottom on the surface of the third cylindrical core mold until the interwoven point reaches the lower end of the third cylindrical core mold, thus obtaining an F-shaped tube;

[0095] In step (2), 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.

[0096] A method for preparing a corrosion-resistant integrally braided F-shaped pipe joint composite material. After the F-shaped pipe is prepared by the above-mentioned braiding method, each core mold is retained; a release cloth is first attached to the inner surface of an outer mold, and then the F-shaped pipe is placed in the outer mold and subjected to a hot pressing treatment (temperature of 190°C, time of 4 minutes, pressure of 0.6MPa). After the hot pressing treatment is completed, the outer mold and each core mold are removed to obtain a corrosion-resistant integrally braided F-shaped pipe joint composite material.

[0097] After the corrosion-resistant integral braided F-shaped pipe joint composite material was immersed in a 10% by mass sulfuric acid solution for 30 days, there was no obvious change in the appearance of the F-shaped pipe joint, and the F-shaped pipe joint had excellent resistance to chemical medium corrosion.

[0098] Example 4

[0099] An integrated braiding method for an F-shaped tube comprises the following steps:

[0100] (1) Material preparation:

[0101] A first cylindrical core mold, a second cylindrical core mold, a third cylindrical core mold, and a bending core mold;

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

[0103] (2) Weaving:

[0104] (2.1) The first cylindrical core mold is arranged vertically, and 2n first yarns are controlled to be interwoven from top to bottom on the surface of the first cylindrical core mold until the interwoven point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

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

[0106] Then, 2n first yarns are controlled to be interwoven from top to bottom on the surface of the bending core mold, and the bending core mold is continuously rotated clockwise during this process, so that the first yarns evenly cover the bending core mold until the interwoven point reaches the connection between the bending core mold and the second cylindrical core mold, at which time the second cylindrical core mold is in a vertical state, with one end connected to the bending core mold at the top and the other end at the bottom;

[0107] (2.3) The second cylindrical core mold is divided into two sections, an upper section and an lower section, and the 2n first yarns are controlled to be interwoven from top to bottom on the surface of the upper section of the second cylindrical core mold until the interwoven point reaches the junction of the upper section and the lower section of the second cylindrical core mold;

[0108] (2.4) After arranging the third cylindrical core mold horizontally, control its left end 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;

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

[0110] Add n second yarns;

[0111] Then, the first group of first yarns and n second yarns are controlled to be interwoven from top to bottom on the lower surface of the second cylindrical core mold until the interwoven point reaches the lower end of the second cylindrical core mold;

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

[0113] Add n third yarns;

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

[0115] In step (2), 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.

[0116] A method for preparing a corrosion-resistant integrally braided F-shaped pipe joint composite material. After the F-shaped pipe is prepared by the above-mentioned braiding method, each core mold is retained; a release cloth is first attached to the inner surface of an outer mold, and then the F-shaped pipe is placed in the outer mold and subjected to a hot pressing treatment (temperature of 195°C, time of 3 minutes, pressure of 0.5MPa). After the hot pressing treatment is completed, the outer mold and each core mold are removed to obtain a corrosion-resistant integrally braided F-shaped pipe joint composite material.

[0117] After the corrosion-resistant integral braided F-shaped pipe joint composite material was immersed in a 10% by mass sulfuric acid solution for 30 days, there was no obvious change in the appearance of the F-shaped pipe joint, and the F-shaped pipe joint had excellent resistance to chemical medium corrosion.

[0118] Example 5

[0119] An integrated braiding method for an F-shaped tube comprises the following steps:

[0120] (1) Material preparation:

[0121] A first cylindrical core mold, a second cylindrical core mold, a third cylindrical core mold, and a bending core mold;

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

[0123] (2) Weaving:

[0124] (2.1) The first cylindrical core mold is arranged vertically, and 2n first yarns are controlled to be interwoven from top to bottom on the surface of the first cylindrical core mold until the interwoven point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

[0125] (2.2) After arranging the second cylindrical core mold horizontally, control its left end to be smoothly connected with the lower end of the first cylindrical core mold through the bending core mold, and the diameter of the second cylindrical core mold is equal to the diameter of the first cylindrical core mold;

[0126] Then, 2n first yarns are controlled to be interwoven from top to bottom on the surface of the bending core mold, and the bending core mold is continuously rotated clockwise during this process, so that the first yarns evenly cover the bending core mold until the interwoven point reaches the connection between the bending core mold and the second cylindrical core mold, at which time the second cylindrical core mold is in a vertical state, with one 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 two sections, an upper section and an lower section, and the 2n first yarns are controlled to be interwoven from top to bottom on the surface of the upper section of the second cylindrical core mold until the interwoven point reaches the junction of the upper section and the lower section of the second cylindrical core mold;

[0128] (2.4) After arranging the third cylindrical core mold horizontally, control its left end 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;

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

[0130] Add n second yarns;

[0131] Then, the first group of first yarns and n second yarns are controlled to be interwoven from top to bottom on the lower surface of the second cylindrical core mold until the interwoven point reaches the lower end of the second cylindrical core mold;

[0132] (2.5) Rotate the third cylindrical core mold 90° clockwise so that the end connected to the second cylindrical core mold is at the top and the other end is at the bottom;

[0133] Add n third yarns;

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

[0135] In step (2), 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.

[0136] A preparation method of a corrosion-resistant integrally braided F-shaped pipe joint composite material, after the F-shaped pipe is prepared by the above-mentioned braiding method, each core mold is retained; first, a release cloth is attached to the inner surface of an outer mold, and then the F-shaped pipe is placed in the outer mold and subjected to a hot pressing treatment (temperature of 200°C, time of 5 minutes, pressure of 1MPa), after the hot pressing treatment is completed, the outer mold and each core mold are removed to obtain a corrosion-resistant integrally braided F-shaped pipe joint composite material.

[0137] After the corrosion-resistant integral braided F-shaped pipe joint composite material was immersed in a 10% by mass sodium hydroxide solution for 30 days, there was no obvious change in the appearance of the F-shaped pipe joint, and the F-shaped pipe joint had excellent resistance to chemical medium corrosion.

[0138] Example 6

[0139] An integrated braiding method for an F-shaped tube comprises the following steps:

[0140] (1) Material preparation:

[0141] A first cylindrical core mold, a second cylindrical core mold, a third cylindrical core mold, and a bending core mold;

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

[0143] (2) Weaving:

[0144] (2.1) The first cylindrical core mold is arranged vertically, and 2n first yarns are controlled to be interwoven from top to bottom on the surface of the first cylindrical core mold until the interwoven point reaches the lower end of the first cylindrical core mold, where n is a positive integer;

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

[0146] Then, 2n first yarns are controlled to be interwoven from top to bottom on the surface of the bending core mold, and the bending core mold is continuously rotated clockwise during this process, so that the first yarns evenly cover the bending core mold until the interwoven point reaches the connection between the bending core mold and the second cylindrical core mold, at which time the second cylindrical core mold is in a vertical state, with one end connected to the bending core mold at the top and the other end at the bottom;

[0147] (2.3) The second cylindrical core mold is divided into two sections, an upper section and an lower section, and the 2n first yarns are controlled to be interwoven from top to bottom on the surface of the upper section of the second cylindrical core mold until the interwoven point reaches the junction of the upper section and the lower section of the second cylindrical core mold;

[0148] (2.4) After arranging the third cylindrical core mold horizontally, control its left end 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;

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

[0150] Add n second yarns;

[0151] Then, the first group of first yarns and n second yarns are controlled to be interwoven from top to bottom on the lower surface of the second cylindrical core mold until the interwoven point reaches the lower end of the second cylindrical core mold;

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

[0153] Add n third yarns;

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

[0155] In step (2), 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.

[0156] A method for preparing a corrosion-resistant integrally braided F-shaped pipe joint composite material. After the F-shaped pipe is prepared by the above-mentioned braiding method, each core mold is retained; a release cloth is first attached to the inner surface of an outer mold, and then the F-shaped pipe is placed in the outer mold and subjected to a hot pressing treatment (temperature of 205°C, time of 5 minutes, pressure of 1.5MPa). After the hot pressing treatment is completed, the outer mold and each core mold are removed to obtain a corrosion-resistant integrally braided F-shaped pipe joint composite material.

[0157] After the corrosion-resistant integral braided F-shaped pipe joint composite material was immersed in a 10% by mass sodium hydroxide solution for 30 days, there was no obvious change in the appearance of the F-shaped pipe joint, and the F-shaped pipe joint had excellent resistance to chemical medium corrosion.

Claims

1. An integrated braiding method for an F-shaped tube, characterized in that: The following steps are involved: (a) arranging the first cylindrical core mold vertically, controlling 2n first yarns to be interwoven from top to bottom on the surface of the first cylindrical core mold until the interweaving point reaches the lower end of the first cylindrical core mold, where n is a positive integer; (b) After the second cylindrical core mold is arranged horizontally, its left end is controlled to be smoothly connected with the lower end of the first cylindrical core mold through the bending core mold, and the diameter of the second cylindrical core mold is equal to the diameter of the first cylindrical core mold; Then, 2n first yarns are controlled to be interwoven from top to bottom on the surface of the bending core mold, and the bending core mold is continuously rotated clockwise during this process, so that the first yarns evenly cover the bending core mold until the interwoven point reaches the connection between the bending core mold and the second cylindrical core mold, at which time the second cylindrical core mold is in a vertical state, with one end connected to the bending core mold at the top and the other end at the bottom; (c) the second cylindrical core mold is divided into two sections, the upper and lower sections, and the 2n first yarns are controlled to be interwoven from top to bottom on the surface of the upper section of the second cylindrical core mold until the interwoven point reaches the junction of the upper section and the lower section of the second cylindrical core mold; (d) after arranging the third cylindrical core mold horizontally, control the left end thereof 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; Divide 2n first yarns into two equal groups; Add n second yarns; Then, the first group of first yarns and n second yarns are controlled to be interwoven from top to bottom on the lower surface of the second cylindrical core mold until the interwoven point reaches the lower end of the second cylindrical core mold; (e) rotating the third cylindrical core mold 90° clockwise so that one end thereof connected to the second cylindrical core mold is at the top and the other end thereof is at the bottom; Add n third yarns; Then, the second group of first yarns and n third yarns are controlled to be interwoven from top to bottom on the surface of the third cylindrical core mold until the interwoven point reaches the lower end of the third cylindrical core mold, thereby obtaining an F-shaped tube.

2. The integrated 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 or 2, characterized in that: 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 thermoplastic polyurethane and continuous glass fiber.

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

5. The integrated braiding method of an F-shaped tube according to claim 3, characterized in that: 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 from the extrusion head of the twin-screw extruder. The temperature range of the twin-screw extruder is 160-220°C.

6. Application of the integrated braiding method of an F-shaped tube as claimed in any one of claims 3 to 5, characterized in that: It is used to prepare a corrosion-resistant integrally braided F-shaped pipe joint composite material. The specific process is: after the F-shaped pipe is prepared, each core mold is retained, the F-shaped pipe is placed in an outer mold and subjected to hot pressing treatment. After the hot pressing treatment, the outer mold and each core mold are removed to obtain a corrosion-resistant integrally braided F-shaped pipe joint composite material.

7. The use according to claim 6, characterized in that: The temperature of the hot pressing treatment is 180-220°C, the time is 2-5min, and the pressure is 0.5-2MPa.

8. The use according to claim 6, characterized in that: Before placing the F-shaped tube in the outer mold, a release cloth is attached to the inner surface of the outer mold.

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