Warp-knitted spacer tube and method for manufacturing a carbon fiber reinforced composite warp-knitted spacer tube

Abstract

The application relates to a weft-knitted spacer tube and a preparation method of a carbon fiber reinforced composite material weft-knitted spacer tube, and belongs to the technical field of textile composite materials. The preparation method of the carbon fiber reinforced composite material weft-knitted spacer tube comprises the following steps: S100, obtaining pre-impregnated carbon fibers; S200, using a weft-knitting method of the weft-knitted spacer tube to knit the pre-impregnated carbon fibers to obtain a carbon fiber weft-knitted spacer tube; and S300, heating and curing the carbon fiber weft-knitted spacer tube to obtain the carbon fiber reinforced composite material weft-knitted spacer tube. The application can quickly prepare the carbon fiber reinforced composite material weft-knitted spacer tube.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of textile composites, and particularly relates to a weft-knitted spacer tube and a preparation method of a carbon fiber reinforced composite weft-knitted spacer tube. BACKGROUND

[0002] At present, in the research of composite materials, lightweight and high strength have become an important development trend of composite materials. The spacer fabric has a unique three-dimensional structure, which is usually composed of two independent fabric layers and a spacer layer, so that it has many excellent properties. The spacer fabric can effectively disperse and absorb energy when subjected to external force, providing excellent cushioning performance, and its composite material also has excellent mechanical properties, and is widely used in the fields of aerospace, transportation, bridge construction, etc. The combination of spacer structure and carbon fiber composite material provides more design space for lightweight design of aerospace structure, and the use of lightweight and efficient advanced structure can further realize the lightweight of the structure. New lightweight structures such as grid shell, stiffened shell and sandwich shell structure, etc.

[0003] The prior art discloses some tubular structures and preparation methods of composite material pipes; the invention patent application CN118792795A discloses a knitted multi-layer hollow heteromorphic cylindrical structure stab-resistant fabric and a preparation method thereof, which can be integrally knitted into a cylinder by means of a four-needle bed computerized flat knitting machine, greatly improving the production efficiency; the invention patent application CN116770501A discloses a warp-knitted seamless tubular composite material and a continuous production method thereof; a warp-knitted seamless tubular composite material preform is in a cylindrical shape, is knitted on a double-needle bed raschel warp knitting machine with 10 guide bars, is integrally formed without a seam, and can be directly sent to a resin impregnation and curing forming device to continuously complete the production of the tubular textile composite material; the invention patent application CN116968339A discloses a fiber fabric composite structure and a preparation method thereof; the fiber fabric composite structure is in a tubular shape, and the tubular structure is a fiber fabric composite honeycomb tube supported by a fiber fabric composite material; the invention patent application CN113977984A discloses a preparation method of a tubular hyperboloid composite structure; the preparation method of the tubular hyperboloid composite structure is prepared by using a mold composed of a metal male die, a female die forming die and a flat plate forming die, realizing the integrity and profile precision of the complex shape, and ensuring the high-quality demolding and smooth shape of the product; the invention patent application CN113320237A discloses a tubular composite material, a preparation method and application thereof; the tubular composite material such as a cylinder or a pipe is provided with a sandwich structure by adding at least one bundle layer between at least two winding layers to enhance the axial strength of the pipe, and is suitable for occasions with high requirements on axial mechanical properties.

[0004] Therefore, most of the tubular structures are manufactured by fiber winding process, interlocking assembly, mold hot pressing and other methods. The fiber winding process can realize continuous fiber laying and is easy to realize automation, but a special mold needs to be designed according to the shape and size of the product, and the cost is high. In the fiber winding process, due to the influence of factors such as fiber tension and winding speed, the fiber winding may be uneven, affecting the performance of the product; although the interlocking assembly and mold hot pressing process can realize the manufacturing of diversified structures, there are still problems such as complex process and high mold cost. At present, there is a lack of a way to quickly form and produce low-cost composite materials with complex structures, and knitting technology is an effective way to realize mass production, automated production and cost reduction. Through the programming setting of computer software, the weaving of complex structure materials can be realized, and the knitted spacer structure has a three-dimensional structure and is also a kind of sandwich structure, which has excellent cushioning performance and energy absorption performance.

[0005] In summary, the existing tubular structure can be manufactured by knitting technology, and most of them are hollow or single-layer structures. The composite material tube is mostly manufactured by curing forming, mold pressing, winding forming and other methods, and the preparation process is complex and tedious. The weft-knitted spacer tube and the carbon fiber reinforced composite weft-knitted spacer tube are not involved in the integrated molding. Therefore, in view of the technical problems of the prior art, combined with the knitting technology, a weft-knitted spacer tube and a carbon fiber reinforced composite weft-knitted spacer tube preparation method are proposed to meet the requirements of integrated molding of the spacer composite fiber reinforced tube. SUMMARY

[0006] The present application provides a weft-knitted spacer tube and a carbon fiber reinforced composite weft-knitted spacer tube preparation method, which aims to partially or completely solve the technical problem of the prior art that carbon fiber reinforced composite spacer tubes cannot be quickly produced. The present application can quickly prepare carbon fiber reinforced composite weft-knitted spacer tubes. In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0007] In a first aspect, a weft-knitted spacer tube preparation method comprises:

[0008] Step S1: knitting on a Sto l l computerized flat knitting machine, forming an inner surface layer and an outer surface layer of the spacer tube by one-in-two looping on the front needle bed and the back needle bed respectively, and the number of knitting rows of the outer surface layer needs to be greater than that of the inner surface layer;

[0009] Step S2: performing spacer stitch purling on the front needle bed and the back needle bed to form the middle spacer layer of the spacer tube, and all purling actions in one spacer need to be staggered with each other, the number of knitting rows of the spacer layer is 1 or 2 or 3 or 4…, and the corresponding number of spacers is one-in-two or one-in-three or one-in-five or one-in-seven…, and so on;

[0010] Step S3: steps S1 and S2 are a cycle knitting action, and steps S1 and S2 are repeated multiple times;

[0011] Step S4, after getting off the machine, the first row of spacer needle coils is stitched with the last row of spacer needle coils to obtain the weft-knitted spacer tube.

[0012] Optionally, the ratio of the number of knitting rows of the inner layer to the number of knitting rows of the outer layer is 1:2 or 1:3 or 2:3 or 3:4.

[0013] In a second aspect, a method for preparing a carbon fiber reinforced composite weft-knitted spacer tube comprises:

[0014] Step S100: obtaining pre-impregnated carbon fibers;

[0015] Step S200: using the weft-knitting method of any one of the first aspect to knit the pre-impregnated carbon fibers to obtain a carbon fiber weft-knitted spacer tube;

[0016] Step S300: heating and curing the carbon fiber weft-knitted spacer tube to obtain a carbon fiber reinforced composite weft-knitted spacer tube.

[0017] Optionally, step S100 comprises:

[0018] Step S101, thermoplastic polyimide TPI liquid resin is diluted with organic solvent N,N-dimethylformamide DMF in proportion;

[0019] Step S102, the diluted thermoplastic polyimide TPI liquid resin is pre-impregnated with carbon fibers in a self-made sizing machine;

[0020] Step S103, the pre-impregnated carbon fibers are preliminarily cured, the volatile part of DMF is volatilized, the surface viscosity of the pre-impregnated composite carbon fibers is reduced, and the pre-impregnated composite carbon fibers are collected.

[0021] Optionally, in step S101, the dilution ratio of thermoplastic polyimide TPI liquid resin to organic solvent N,N-dimethylformamide DMF is 1:2 or 1:3 or 1:4 or 1:5 or 2:3.

[0022] Optionally, the temperature and time of preliminary curing are 20-80℃ and 10-60min.

[0023] Optionally, the temperature and time of heating and curing are 180-260℃ and 30-90min.

[0024] Optionally, step S300 comprises: placing the carbon fiber weft-knitted spacer tube into an oven for heating and curing to obtain a carbon fiber reinforced composite weft-knitted spacer tube.

[0025] The application has the following beneficial effects:

[0026] (1) In the present application, the weaving is carried out on the Stoll computerized flat knitting machine, has a spacing structure, is integrally woven, and can adjust the thickness and width of the pipe according to needs through software, realizes rapid production, saves manpower, raw materials and time cost, and avoids waste of resources.

[0027] (2) In the present application, no mold is needed, and no secondary composite treatment is needed, so that the production cost is greatly reduced. The spacing structure is uniformly distributed, so that the composite pipe can withstand pressure to a certain extent, increases the stress range and stress direction of the composite pipe, reduces the material and weight compared with the solid structure, saves the cost, and has stronger stress capacity compared with the hollow structure. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0029] Figure 1 It is a flowchart of a weft-knitted spacing pipe preparation method of the present application.

[0030] Figure 2 It is a weaving process schematic diagram of the weft-knitted spacing pipe of the present application.

[0031] Figure 3 It is a structure schematic diagram of the weft-knitted spacing pipe of the present application.

[0032] Figure 4 It is a flowchart of a carbon fiber reinforced composite material weft-knitted spacing pipe preparation method of the present application.

[0033] Figure 5 It is a cross-sectional schematic diagram of the carbon fiber reinforced composite material weft-knitted spacing pipe of the present application.

[0034] Figure 6 It is a physical schematic diagram of the carbon fiber reinforced composite material weft-knitted spacing pipe of the present application.

[0035] The drawings are used to provide further understanding of the present application, and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application, and do not constitute a limitation to the present application. DETAILED DESCRIPTION

[0036] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts should fall within the scope of the present application.

[0037] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. "Include" can be understood as at least including. In order to make the purpose, technical solutions and advantages of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the drawings.

[0038] A method of making a weft-knitted spacer tube

[0039] In a first aspect, as shown in the drawings, a weft-knitted spacer tube preparation method comprises: Figures 1 to 6

[0040] Step S1, knitting on a Stoill computerized knitting machine, forming inner and outer surface layers of the spacer tube by forming a loop every other needle on the front and back needle beds, the number of knitting rows of the outer surface layer being greater than that of the inner surface layer;

[0041] In some embodiments, the number of knitting rows can be adjusted according to the required surface layer width. It should be noted that, in order to form a tubular shape, the number of knitting rows of the outer surface layer 10 needs to be greater than that of the inner surface layer 30.

[0042] Step S2, forming the intermediate spacer layer of the spacer tube by tucking on the front and back needle beds, all tucking actions in one spacer need to be staggered with each other, the number of knitting rows of the spacer layer being 1 or 2 or 3 or 4…, and the corresponding number of spacers being one every other needle or one every third needle or one every fifth needle or one every seventh needle, and so on;

[0043] In some embodiments, the number of knitting rows of the spacer layer 20 can be adjusted according to the required spacer thickness. It should be noted that, in order to avoid compression of the edges of the fabric, the position of the tucking row in one spacer is adjusted so that the edge tuckings are evenly distributed;

[0044] Step S3, steps S1 and S2 are a loop knitting action, and steps S1 and S2 are repeated multiple times;

[0045] ​Step S4, after getting off the machine, the first row of spacer stitches is sewn with the last row of spacer stitches to obtain the weft-knitted spacer tube.

[0046] In the present application, the knitting is carried out on a Sto l l computerized flat knitting machine, has a spacer structure, is integrally woven, and the thickness and width of the tube can be adjusted as needed through software, realizing rapid production, saving labor, raw materials and time cost, and avoiding waste of resources

[0047] Optionally, the ratio of the number of knitted rows of the inner layer to the number of knitted rows of the outer layer is 1:2 or 1:3 or 2:3 or 3:4.

[0048] In some embodiments, the ratio of the number of knitted rows of the inner layer to the number of knitted rows of the outer layer is 1:2 or 1:3 or 2:3 or 3:4. Of course, those skilled in the art can also reasonably set the ratio of the number of knitted rows of the inner layer to the number of knitted rows of the outer layer according to actual needs.

[0049] In the present application, the automatic characteristics of the Sto l l computerized flat knitting machine are used to quickly adjust the thickness and width of the spacer tube according to actual needs, greatly shorten the production cycle, greatly reduce the labor input in the traditional multi-step process, significantly reduce the production cost, the ratio of the number of knitted rows of the inner layer to the number of knitted rows of the outer layer (for example, 1:2, 1:3, 2:3 or 3:4) can be flexibly adjusted according to actual needs to meet diversified application scenarios, the spacer structure design enhances the air permeability, elasticity and comfort of the product, improves the functionality and user experience, improves the production efficiency, provides technical support for personalized customization, and has wide technical and market application prospects.

[0050] A method of making a carbon fibre reinforced composite weft-knitted spacer tube

[0051] In a second aspect, a method for preparing a carbon fiber reinforced composite material weft-knitted spacer tube comprises:

[0052] Step S100: obtaining pre-impregnated carbon fibers;

[0053] Step S200: using the weft-knitting method of the weft-knitted spacer tube of any one of the first aspect to knit the pre-impregnated carbon fibers to obtain a carbon fiber weft-knitted spacer tube;

[0054] Step S300: heating and curing the carbon fiber weft-knitted spacer tube to obtain a carbon fiber reinforced composite material weft-knitted spacer tube.

[0055] In the present application, no mold is needed, and no secondary composite treatment is needed, greatly reducing the production cost. The spacer structure is uniformly distributed, which can enable the composite tube to withstand pressure to some extent, increase the stress range and stress direction of the composite tube, reduce the material and weight compared with solid structure parts, save costs, and at the same time, have stronger stress capacity compared with hollow structure parts.

[0056] Optionally, step S100 includes:

[0057] Step S101: Dilute the thermoplastic polyimide (TPI) liquid resin with the organic solvent N,N-dimethylformamide (DMF) in a certain proportion;

[0058] Step S102: The diluted thermoplastic polyimide (TPI) liquid resin is pre-impregnated with carbon fiber in a sizing machine.

[0059] Step S103: The pre-impregnated carbon fiber is initially cured to volatilize some DMF, reduce the surface viscosity of the pre-impregnated composite carbon fiber, and the pre-impregnated composite carbon fiber is collected.

[0060] In this invention application, firstly, by diluting thermoplastic polyimide (TPI) liquid resin with the organic solvent N,N-dimethylformamide (DMF) in a specific ratio, the resin viscosity can be effectively adjusted, ensuring that it uniformly covers the carbon fiber surface during impregnation. This not only improves the impregnation quality but also enhances the interfacial bonding performance of the subsequent composite material. Secondly, pre-impregnating the diluted TPI liquid resin and carbon fiber in a sizing machine achieves precise control of impregnation conditions, better ensuring uniform distribution between the carbon fiber and resin, and improving the overall mechanical properties and stability of the composite material. Furthermore, by initially curing the pre-impregnated carbon fiber and volatilizing some of the DMF, the surface viscosity of the composite carbon fiber is effectively reduced, avoiding fiber entanglement or handling difficulties caused by excessive viscosity, thus improving the processability and surface quality of the composite material. Finally, by collecting the pre-impregnated composite carbon fiber, continuous and automated production is achieved, significantly reducing manual intervention, lowering production costs, and improving production efficiency. This method is suitable for the preparation of weft-knitted spacer tubes of carbon fiber reinforced composite materials.

[0061] Optionally, step S300 includes: placing the carbon fiber weft-knitted spacer tube in an oven for heating and curing to obtain a carbon fiber reinforced composite weft-knitted spacer tube.

[0062] In this invention application, firstly, the heating and curing process enables the thermoplastic resin to fully penetrate and uniformly coat the carbon fibers, forming a stable three-dimensional structure, which improves the mechanical properties of the composite material and meets the industrial demand for high-performance materials; secondly, the heating and curing process is simple to operate, highly controllable, and can achieve mass production, significantly reducing production costs and improving production efficiency.

[0063] Optionally, in step S101, the dilution ratio of thermoplastic polyimide TPI liquid resin to organic solvent N,N-dimethylformamide DMF is 1:2, 1:3, 1:4, 1:5, or 2:3.

[0064] In this invention application, by precisely controlling the dilution ratio (1:2 or 1:3) of TPI liquid resin and DMF, the resin viscosity can be effectively adjusted, enabling the resin to uniformly impregnate carbon fibers, improve the interfacial bonding strength, and enhance the overall mechanical properties and stability of the composite material.

[0065] Optionally, the initial curing temperature and time are 20℃-80℃ and 10-60min;

[0066] In this invention application, the initial curing temperature and time are 20℃-80℃ and 10-60min. Preferably, the initial curing temperature (25℃) and time (30min) settings can reduce the surface viscosity of the pre-impregnated carbon fiber with lower energy consumption, avoid fiber entanglement problems, simplify subsequent processing procedures, and improve production efficiency.

[0067] Optionally, the temperature and time for heat curing are 180℃-260℃ and 30-90min.

[0068] In this invention application, the heating and curing temperature and time are 180℃-260℃ and 30-90min. Preferably, the heating and curing temperature (180℃) and time (90min) ensure that the thermoplastic polyimide (TPI) liquid resin is fully cured to form a stable three-dimensional network structure. This not only enhances the mechanical properties of the composite material, but also ensures its excellent heat resistance and chemical stability, meeting the performance requirements of carbon fiber reinforced composite weft-knitted spacer tubes.

[0069] Exemplary description of a method of knitting a weft-knitted spacer tube A, weft-knitted spacer tube B

[0070] (1) The weaving method of the weft-knitted spacer tube A includes:

[0071] Step S1A: Knit on the Sto ll computer flat knitting machine, forming loops with one row spaced on each of the front and back needle beds to create the inner and outer layers of the spacer tube. The outer layer is formed with 3 rows of spaced needles, and the inner layer is formed with 2 rows of spaced needles.

[0072] Step S2A: Perform intermittent stitch gathering on the front and back needle beds to form the middle interval layer of the interval tube. The number of rows in the interval layer is 4. The interval layer adopts a one-interval seven-gathering method. All gathering actions within an interval must be staggered.

[0073] In some embodiments, the number of weaving rows can be adjusted according to the required interval thickness. It should be noted that, in order to avoid compression at the edge of the fabric, the position of the tufting rows within an interval should be adjusted to ensure that the tufting at the edge is evenly distributed.

[0074] Step S3A, steps S1A and S2A constitute a loop weaving action, and steps S1A and S2A are repeated multiple times.

[0075] Step S4A: After the machine is off, sew the first row of spacer loops to the last row of spacer loops to obtain the weft-knitted spacer tube.

[0076] (2) The weaving method of the weft-knitted spacer tube B includes:

[0077] Step S1 B: Knit on the Stoll computerized flat knitting machine, forming loops with one row spaced on each of the front and back needle beds to create the inner and outer layers of the spacer tube. The outer layer is formed with 4 rows of spaced needles, and the inner layer is formed with 3 rows of spaced needles.

[0078] Step S2B: Perform intermittent stitch gathering on the front and back needle beds to form the middle interval layer of the interval tube. The number of rows for the interval layer is 3. The interval layer adopts a one-interval five-gathering method. All gathering actions within an interval must be staggered.

[0079] In some embodiments, the number of weaving rows can be adjusted according to the required interval thickness. It should be noted that, in order to avoid compression at the edge of the fabric, the position of the tufting rows within an interval should be adjusted to ensure that the tufting at the edge is evenly distributed.

[0080] Step S3B, steps S1B and S2B constitute a loop weaving action, and steps S1B and S2B are repeated multiple times.

[0081] Step S4B: After the machine is removed from the knitting machine, the first row of spacer loops is sewn together with the last row of spacer loops to obtain the weft-knitted spacer tube.

[0082] A method of making a carbon fibre reinforced composite weft-knitted spacer tube A, carbon fibre reinforced composite weft-knitted spacer tube B Exemplary description

[0083] (1) Carbon fiber reinforced composite weft-knitted spacer tube A

[0084] Step S100A: Obtain pre-impregnated carbon fibers;

[0085] Step S200A: The pre-impregnated carbon fiber is woven using the weft-knitted spacer tube A weft-knitted method to obtain carbon fiber weft-knitted spacer tube A;

[0086] Step S300A: Heat and cure the carbon fiber weft-knitted spacer tube A to obtain carbon fiber reinforced composite material weft-knitted spacer tube A.

[0087] Step S100A includes:

[0088] Step S101A: Dilute the thermoplastic polyimide TPI liquid resin with the organic solvent N,N-dimethylformamide DMF at a ratio of 1:2;

[0089] Step S102A: The diluted thermoplastic polyimide TPI liquid resin is pre-impregnated with carbon fiber in a sizing machine.

[0090] Step S103A: The pre-impregnated carbon fiber is initially cured at 25°C for 30 minutes to volatilize some DMF, reduce the surface viscosity of the pre-impregnated composite carbon fiber, and collect the pre-impregnated composite carbon fiber.

[0091] Step S300A includes: placing the carbon fiber weft-knitted spacer tube A into an oven for heating and curing at 180°C for 90 minutes to obtain the carbon fiber reinforced composite weft-knitted spacer tube A.

[0092] (2) Carbon fiber reinforced composite weft-knitted spacer tube B

[0093] Step S100B: Obtain pre-impregnated carbon fibers;

[0094] Step S200B: Use the weaving method of weft-knitted spacer tube B to weave the pre-impregnated carbon fiber to obtain carbon fiber weft-knitted spacer tube B;

[0095] Step S300A: Heat and cure the carbon fiber weft-knitted spacer tube B to obtain carbon fiber reinforced composite material weft-knitted spacer tube B.

[0096] Step S100B includes:

[0097] Step S101 B: Dilute the thermoplastic polyimide TPI liquid resin with the organic solvent N,N-dimethylformamide DMF at a ratio of 1:3;

[0098] Step S102B involves pre-impregnating diluted thermoplastic polyimide TPI liquid resin with carbon fiber in a homemade sizing machine.

[0099] Step S103B: The pre-impregnated carbon fiber is initially cured at 25°C for 20 minutes to volatilize some DMF, reduce the surface viscosity of the pre-impregnated composite carbon fiber, and collect the pre-impregnated composite carbon fiber.

[0100] Step S300B includes: placing the carbon fiber weft-knitted spacer tube B into an oven for heating and curing at 180°C for 90 minutes to obtain the carbon fiber reinforced composite weft-knitted spacer tube B.

[0101] The accompanying drawings are merely one embodiment of this invention, and the actual structure is not limited to this. In conclusion, if those skilled in the art, inspired by these drawings, design similar structures and embodiments without departing from the spirit of this invention, such designs should fall within the scope of protection of this invention.

Claims

1. A method for preparing a carbon fiber reinforced composite material weft-knitted spacer tube, characterized by, The application relates to a carbon fiber reinforced composite material weft-knitted spacer tube and a preparation method thereof. Step S100: obtaining pre-impregnated carbon fibers, comprising: Step S101, diluting the thermoplastic polyimide TPI liquid resin with an organic solvent N,N-dimethylformamide DMF in proportion; Step S102, pre-impregnating the diluted thermoplastic polyimide TPI liquid resin with the carbon fibers in a sizing machine; Step S103, preliminarily curing the pre-impregnated carbon fibers, volatilizing part of the DMF, reducing the surface viscosity of the pre-impregnated composite carbon fibers, and collecting the pre-impregnated composite carbon fibers; Step S200: weaving the pre-impregnated carbon fibers by using a weft-knitting spacer tube weaving method to obtain carbon fiber weft-knitted spacer tubes, comprising: Step S1, weaving on a Stoll computerized flat knitting machine, forming an inner surface layer and an outer surface layer of the spacer tube by respectively forming one-in-one loops on the front needle bed and the back needle bed, and the number of weft rows of the outer surface layer needs to be greater than that of the inner surface layer; Step S2, forming a middle spacer layer of the spacer tube by performing spacer needle tuck stitches on the front needle bed and the back needle bed, all tuck stitch actions in one spacer need to be staggered with each other, the number of weft rows of the spacer layer is 1 or 2 or 3 or 4, and the corresponding spacer needle number is one-in-one or one-in-three or one-in-five or one-in-seven, and so on; Step S3, step S1 and S2 are one cycle of weaving actions, and steps S1 and S2 are repeatedly cycled for multiple times; Step S4, after the machine is turned off, the first row of spacer needle loops is sewn with the last row of spacer needle loops to obtain the weft-knitted spacer tube; Step S300: heating and curing the carbon fiber weft-knitted spacer tube to obtain a carbon fiber reinforced composite material weft-knitted spacer tube.

2. The method for preparing a carbon fiber reinforced composite weft-knitted spacer tube according to claim 1, characterized in that, The ratio of the number of weft rows of the inner surface layer to the number of weft rows of the outer surface layer is 1:2 or 1:3 or 2:3 or 3:

4.

3. The method for preparing a carbon fiber reinforced composite weft-knitted spacer tube according to claim 1, characterized in that, In step S101, the dilution ratio of the thermoplastic polyimide TPI liquid resin to the organic solvent N,N-dimethylformamide DMF is 1:2 or 1:3 or 1:4 or 1:5 or 2:

3.

4. The method for preparing a carbon fiber reinforced composite weft-knitted spacer tube according to claim 1, characterized in that, The temperature and time of the preliminary curing are 20-80 DEG C and 10-60 min.

5. The method for preparing a carbon fiber reinforced composite weft-knitted spacer tube according to claim 1, characterized in that, The temperature and time of the heating and curing are 180-260 DEG C and 30-90 min.

6. The method for preparing a carbon fiber reinforced composite weft-knitted spacer tube according to claim 1, characterized in that, Step S300 comprises: placing the carbon fiber weft-knitted spacer tube into an oven for heating and curing to obtain a carbon fiber reinforced composite material weft-knitted spacer tube.

Images