Composite external grid rib bearing cylinder, forming die and preparation method

Abstract

The application provides a composite external grid rib bearing cylinder, a forming die and a preparation method. The bearing cylinder is integrally prepared by extrusion and die closing of a metal forming die. The prepreg of fibers and resin is laid according to a set laying angle. The preparation is mainly integrated preparation through pre-extrusion forming and extrusion and die closing. The application overcomes the problems of the traditional metal structure process, such as the complex process of the integral mode of the net cylinder after forming and the L-shaped rib splicing, the weak mechanical properties at the splicing part, the easy delamination defects of the glue joint surface and the like. The composite external grid rib bearing cylinder has better mechanical properties, is more lightweight, has better structural stability and can better meet the performance requirements of aerospace.

Description

Technical Field

[0001] This invention relates to the field of composite material applications, specifically providing a composite material external mesh reinforcement support cylinder, molding die, and preparation method. Background Technology

[0002] Carbon fiber composites are lightweight materials with superior comprehensive performance. Therefore, load-bearing cylinders in satellites and other spacecraft are mostly made of carbon fiber composites. Carbon fiber composite externally reinforced load-bearing cylinders have significant application value in aerospace structures and are widely used in the load-bearing structures of spacecraft and aircraft. As the main load-bearing component of satellites and other aerospace products, the load-bearing cylinder must ensure high rigidity. Currently, improving its rigidity is mostly achieved by arranging grid-like reinforcing ribs on the cylinder body. These reinforcing ribs are divided into internal and external types, determined according to the product's application requirements. When the reinforcing ribs are internal, the connection between the reinforcing ribs and the cylinder body is usually achieved through post-bonding. This results in a lack of a continuous fiber layer between the cylinder body and the reinforcing ribs, affecting the torsional performance of the load-bearing cylinder structure and thus reducing the service life of aerospace products.

[0003] The main molding methods for carbon fiber composite external mesh reinforcement load-bearing cylinders include compression molding and vacuum bag-autoclave molding. However, each of these methods has its drawbacks. Vacuum bag-autoclave molding results in a rough inner surface for the external mesh reinforcement load-bearing cylinder, which can damage the fibers and reduce product strength during subsequent surface processing. Furthermore, these methods are mostly used for manufacturing clean cylinders or internally reinforced load-bearing cylinders, and are rarely used for manufacturing externally mesh reinforcement load-bearing cylinders. Existing externally mesh reinforcement load-bearing cylinder structures are mostly assembled from metal structures and composite material skin shells and reinforcements, resulting in heavy weight, weak mechanical properties at joints, and a tendency for delamination defects at the adhesive surface. Summary of the Invention

[0004] To solve the above problems, this invention provides a composite material external mesh reinforcement load-bearing cylinder, a molding die, and a preparation method.

[0005] The composite material external mesh reinforcement load-bearing cylinder provided by the present invention includes:

[0006] The shell skin is a hollow cylindrical structure;

[0007] The upper flange reinforcement area and the lower flange reinforcement area are both hollow annular structures, and are respectively located at the openings at both ends of the shell skin;

[0008] The mesh reinforcement is set on the outer wall of the shell skin. The mesh reinforcement includes circumferential reinforcement and longitudinal reinforcement. The circumferential reinforcement is evenly distributed along the axial direction of the shell skin, and the longitudinal reinforcement is parallel to the axis of the shell skin and is evenly distributed on the outer wall of the shell skin.

[0009] The shell skin, upper flange reinforcement area, lower flange reinforcement area and grid reinforcement are all integral structures, and are made of fiber and resin. In the fiber and resin composite material, the volume fraction of fiber is 60% ± 3%.

[0010] Preferably, the fiber is made of glass fiber, quartz fiber or high silica fiber; the resin is made of cyanate resin, epoxy resin or acetal resin.

[0011] Preferably, each group of fiber and resin composite material is made up of 5 layers of fiber and resin prepreg, with the laying angles being 0°, 90°, +θ°, 0°, and -θ° respectively. The axial direction of the shell skin is 0°, 30°≤θ°≤60°, and the laying thickness of each layer is 0.1 to 0.2 mm.

[0012] A molding die for a composite material external mesh reinforcement load-bearing cylinder includes, from the inside out, the following components concentrically arranged: cylinder core, core mold, outer segments, and pressure cylinder;

[0013] The core is cylindrical and is used to compress the inner wall of the composite material external mesh reinforcement load-bearing cylinder;

[0014] The core mold is connected to the outer segment. The core mold consists of multiple metal blocks, which are made of aluminum alloy. The rest of the structure is made of carbon steel. The gaps between the metal blocks are used for the extrusion molding of the mesh reinforcement.

[0015] The outer segment consists of at least two pieces, and a pre-compression plate and a pre-compression ejector screw are provided around the outer segment. During the extrusion and mold closing process, the pre-compression ejector screw is used to pre-compress and form the mesh reinforcement.

[0016] The pressure cylinder is used to apply pressure perpendicular to the axial direction to the outer segments. A base plate is connected to the lower end of the pressure cylinder. The upper surface of the base plate is provided with a first limiting structure to avoid excessive compression of the composite material external mesh reinforcement support cylinder, which would cause its shell skin to become too thin. Observation gaps are left at equal intervals at the connection between the base plate and the pressure cylinder to observe the distance between the composite material external mesh reinforcement support cylinder and the base plate.

[0017] A top cover plate is connected to the upper end of the pressure cylinder. The top cover plate is coaxially connected to the bottom plate through a positioning pin. A second limiting structure is provided on the lower surface of the top cover plate to prevent the outer segments from tilting during the extrusion and mold closing process.

[0018] Both the base plate and the top cover plate are equipped with mold closing gap observation holes, which are used to observe the extrusion molding of the composite material external mesh reinforcement support cylinder by the molding die.

[0019] Preferably, the surface of the pressure cylinder is provided with a threaded through hole, the side pressure screw is locked with the threaded through hole, and the top of the side pressure screw applies pressure perpendicular to the axial direction to the outside through the threaded through hole.

[0020] Preferably, the outer lobes are 4 pieces.

[0021] Preferably, the upper cover plate and the bottom plate have through holes to accommodate positioning pins, and there are two positioning pins.

[0022] A method for preparing a composite material external mesh reinforcement load-bearing cylinder, comprising the following steps: The method utilizes a molding die to process the composite material external mesh reinforcement load-bearing cylinder.

[0023] S1. Fix the core to the base plate and install the lower flange reinforcement area and shell skin;

[0024] S2. Lay the metal blocks according to the shape of the mesh reinforcement to be processed, and fix the core mold after laying the metal blocks on the outer segment. Lay the fiber and resin prepreg in groups of five layers in the gaps of the metal blocks. The laying angle of each group is 0°, 90°, +θ°, 0°, -θ°. The axial direction of the shell skin is 0°, 30°≤θ°≤60°. The laying thickness of each layer is 0.2mm. The fiber and resin prepreg in the gaps of the metal blocks is pre-pressed in sections by using a pre-press plate and pre-press screws. After the section pre-pressing is completed, the pre-press screws are removed.

[0025] S3. Assemble the core and fix the outer segment with the core mold. The pressure cylinder applies a pressure perpendicular to the axial direction to the metal block through the side pressure screws. The side pressure screws are screwed in to the same length.

[0026] S4. Lay out the upper flange reinforcement area, install the upper cover plate, and insert the positioning pin to prevent the upper cover plate from misaligning with the base plate; screw the axial pressure screws into the threaded holes on the preload plates at the upper and lower ends of the outer segment.

[0027] S5. Screw in the axial pressure screw and the side pressure screw to apply pressure, and judge the extrusion mold closing condition through the mold closing gap observation hole and the observation gap.

[0028] S6. Perform heat curing at a temperature of 110℃~150℃ for 2~4 hours.

[0029] S7. Cool to below 40℃ and demold to complete the preparation of the composite material external mesh reinforcement load-bearing cylinder.

[0030] Preferably, when installing the top cover, first unscrew the side pressure screws by 1 to 2 turns to avoid excessive pressure on the side pressure screws, which could make the top cover difficult to install.

[0031] Preferably, mesh reinforcements that meet different needs can be produced by replacing metal blocks of different thicknesses and sizes.

[0032] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0033] The molding die of this invention is made of metal, with a smooth surface and high dimensional accuracy. The inner surface of the composite material external mesh reinforcement support cylinder after molding is smooth, and the inner cavity size can be precisely controlled. Subsequent surface processing will not damage the fibers, avoiding a reduction in the strength of the composite material external mesh reinforcement support cylinder due to post-processing. The molding die of this invention is inexpensive and can produce composite material external mesh reinforcement support cylinders of different sizes.

[0034] The preparation method of the present invention adopts the integrated processing of shell skin and mesh reinforcement, which avoids the later splicing of traditional composite material shell skin and mesh reinforcement, and avoids problems such as weak mechanical properties at the splicing point and easy delamination defects at the adhesive surface. Attached Figure Description

[0035] Figure 1 This is a structural diagram of a composite material external mesh reinforcement load-bearing cylinder provided according to an embodiment of the present invention;

[0036] Figure 2 This is a structural diagram of the molding die for a composite material external mesh reinforcement load-bearing cylinder provided in an embodiment of the present invention;

[0037] Figure 3 This is a cross-sectional view of the molding die for a composite material external mesh reinforcement load-bearing cylinder provided in an embodiment of the present invention;

[0038] Figure 4 This is a flowchart illustrating a method for preparing a composite material externally reinforced load-bearing cylinder according to an embodiment of the present invention;

[0039] Figure 5 This is a structural diagram of a single outer lobe pre-compression molding according to an embodiment of the present invention.

[0040] The reference numerals in the figures include:

[0041] Shell skin 1, upper flange reinforcement area 2, lower flange reinforcement area 3, mesh reinforcement 4, ring reinforcement 41, longitudinal reinforcement 42;

[0042] Core 110, core mold 120, outer segment 130, pressure cylinder 140, upper cover plate 150, bottom plate 160, positioning pin 170, pre-pressure plate 180, pre-pressure ejector screw 190, observation gap 200, mold closing gap observation hole 210, side pressure screw hole 220, axial pressure screw hole 230. Detailed Implementation

[0043] In the following description, embodiments of the invention will be described with reference to the accompanying drawings. In the description below, the same modules are denoted by the same reference numerals. Where the same reference numerals are used, their names and functions are also the same. Therefore, their detailed description will not be repeated.

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0045] Figure 1 The structure of a composite material external mesh reinforcement load-bearing cylinder provided according to an embodiment of the present invention is shown.

[0046] like Figure 1 As shown in the embodiment of the present invention, the composite material external mesh reinforcement load-bearing cylinder is integrally molded through a fiber and resin prepreg laying process. The fibers in the prepreg can be one of glass fiber, quartz fiber, high silica fiber, or carbon fiber; the resin in the prepreg can be one of cyanate resin, epoxy resin, acetal phenolic resin, bismaleimide resin, polyimide resin, or phthalic acid cyanide resin. The volume fraction of the fibers is 60% ± 3%.

[0047] The composite material externally reinforced load-bearing cylinder includes: a shell skin 1, an upper flange reinforcement area 2, a lower flange reinforcement area 3, and a mesh reinforcement 4, wherein:

[0048] The shell skin 1 is a hollow cylindrical structure. An upper flange reinforcement area 2 and a lower flange reinforcement area 3 are provided at the axial openings at both ends of the shell skin 1. Both the upper flange reinforcement area 2 and the lower flange reinforcement area 3 are hollow annular structures. The inner surface of the shell skin 1 is smooth. A grid rib 4 is provided on the outer surface of the shell skin 1. The grid rib 4 includes annular ribs 41 and longitudinal ribs 42. The annular ribs 41 are evenly distributed along the axial direction of the shell skin 1; the longitudinal ribs 42 are parallel to the axis of the shell skin 1 and are evenly distributed on the outer wall of the shell skin 1.

[0049] The shell skin 1, upper flange reinforcement area 2, lower flange reinforcement area 3, and mesh reinforcement 4 of the composite material external mesh reinforcement load-bearing cylinder are all integral structures. The composite material external mesh reinforcement load-bearing cylinder is made of multiple sets of fiber and resin composite materials. Each set of fiber and resin composite materials consists of 5 layers of fiber and resin prepreg. The axial direction of the shell skin 1 is defined as 0°, and the laying angles are 0°, 90°, 45°, 0°, and -45° respectively. The thickness of a single layer of prepreg is 0.2 mm, and the coefficient of thermal expansion in the 0° direction of a single layer is a1, -1×10. -6 / K<a1<1×10 -6 / K, the coefficient of thermal expansion of a single layer in the 90° direction is a2, 15×10 -6 / K<a2<35×10 -6 / K, where K is the temperature constant.

[0050] The composite material external mesh reinforcement load-bearing cylinder of this invention does not require surface processing of the inner wall, and is manufactured by integral processing of the shell skin and mesh reinforcement, avoiding the later splicing of the traditional composite material shell skin cylinder and mesh reinforcement, and avoiding problems such as weak mechanical properties at the splicing point and easy delamination defects at the adhesive surface.

[0051] Figure 2 The structure of a molding die for a composite material external mesh reinforcement load-bearing cylinder provided according to an embodiment of the present invention is shown.

[0052] Figure 3 A cross-sectional view of the molding die for a composite material external mesh reinforcement load-bearing cylinder provided according to an embodiment of the present invention is shown.

[0053] Figure 5 The diagram illustrates a structure for pre-compression molding of a single outer lobe according to an embodiment of the present invention.

[0054] like Figure 2 , Figure 3 and Figure 5 As shown, the molding die for the composite material external mesh reinforcement load-bearing cylinder provided in this embodiment of the invention includes, from the inside out, the following concentrically arranged components: cylinder core 110, core mold 120, outer segment 130, and pressure cylinder 140, as well as an upper cover plate 150, a bottom plate 160, and a positioning pin 170.

[0055] The core 110 is a hollow cylinder used to compress the inner wall of the composite material external mesh reinforcement support cylinder. When the fiber and resin prepreg is laid, the fiber and resin prepreg is laid on the side of the core 110.

[0056] The core mold 120 is set on the outside of the core 110 and together with the core 110 completes the extrusion molding. The core mold 120 is composed of multiple metal blocks of the same size. In the molding die of the composite material external mesh reinforcement load-bearing cylinder, the metal blocks are made of aluminum alloy, and the other structures are made of carbon steel. The thermal expansion coefficient of aluminum alloy is relatively large, which makes the mesh reinforcement 4 more compact. When the metal blocks are arranged, the gaps between the metal blocks are used for the extrusion molding of the mesh reinforcement 4. The outside of the core mold 120 is connected to the outer segment 130.

[0057] The outer segment 130 includes four segments, which are divided into four pre-compression forming areas and are equipped with straight opening structures that mutually limit each other, thus preventing the prepreg from overflowing during the pressure curing process. The outer segment 130 has pre-reserved mounting holes for pre-compression tooling plates around its perimeter. The outer segment 130 is equipped with a pre-compression plate 180 and a pre-compression ejector screw 190 around its perimeter. The pre-compression ejector screw 190 is threadedly connected to the pre-compression plate 180, and the top of the pre-compression ejector screw 190 rests against the side of the metal block at the edge. The core mold 120 can pre-compress the mesh ribs 4 on each outer segment 130.

[0058] The pressure cylinder 140 is located outside the outer segment 130. A threaded hole is opened on the side of the pressure cylinder 140 corresponding to the position of the metal block. A side pressure screw can be screwed into this hole. The outer segment 130 applies pressure perpendicular to the axial direction, further pressurizing the metal block. A base plate 160 is connected to the lower end of the pressure cylinder 140. A first limiting structure is provided on the upper surface of the base plate 160 to prevent excessive compression of the composite material external mesh reinforcement support cylinder during the extrusion molding process, which could cause its shell skin 1 to become too thin. An observation gap 200 is provided at equal intervals at the connection between the base plate 160 and the pressure cylinder 140 for observing the distance between the composite material external mesh reinforcement support cylinder and the base plate 160.

[0059] A top cover plate 150 is connected to the upper end of the pressure cylinder 140. The top cover plate 150 and the bottom plate 160 have through holes to accommodate positioning pins 170. There are two positioning pins 170. The top cover plate 150 is coaxially connected to the bottom plate 160 through the positioning pins 170. A second limiting structure is provided on the lower surface of the top cover plate 150 to prevent the outer segment 130 from tilting during the extrusion molding process. Both the bottom plate 160 and the top cover plate 150 are provided with mold closing gap observation holes 210 to observe the extrusion molding of the composite material external mesh reinforcement support cylinder by the molding die.

[0060] Figure 4 The flowchart illustrates a method for preparing a composite material external mesh reinforcement load-bearing cylinder according to an embodiment of the present invention.

[0061] like Figure 4 and Figure 5 As shown, the method for preparing a composite material external mesh reinforcement load-bearing cylinder provided in this embodiment of the invention utilizes a molding die to process the composite material external mesh reinforcement load-bearing cylinder, specifically including the following steps:

[0062] S1. Prepare the molding mold for the composite material external mesh reinforcement load-bearing cylinder. Fix the cylinder core 110 on the base plate 160. Lay down the flange reinforcement area 3 and the shell skin 1, which is made of 4 groups of fiber and resin composite materials. Each group of fiber and resin composite materials is made of 5 layers of fiber and resin prepreg. The axial direction of the shell skin 1 is specified as 0°, the laying angle of the first layer is 0°, and the layering sequence is 0°, 90°, 45°, 0°, -45° on the cylinder core 1. 10. Carbon fiber and epoxy resin prepreg are laid on top. The thickness of a single layer of prepreg is 0.2 mm. In addition, the laying angle can be 0°, 90°, +θ°, 0°, -θ°, 30°≤θ°≤60°. The thickness of each layer can be 0.1~0.2 mm. For the layer with a laying angle of 90°, thin strips of prepreg with a width of 10 mm~20 mm are used for winding. At the corners, the fiber should be kept as continuous as possible, and prepreg is reserved at the two reinforcement areas of the upper flange.

[0063] S2. Lay metal blocks on the outer segment 130 according to the shape of the mesh reinforcement 4 to be processed, and fix the core mold after laying the metal blocks on the outer segment 130 with screws. Lay carbon fiber and epoxy resin prepreg in groups of five layers in the gaps of the metal blocks in the order of 0°, 90°, 45°, 0°, -45°. Prepress the carbon fiber and epoxy resin prepreg in the gaps of the metal blocks in sections using the prepress plate 180 and the prepress screw 190. Screw the prepress screw 190 into the extruded metal block. After a period of time, the section prepress molding is completed, and the mesh reinforcement 4 is preformed. After the section prepress molding is completed, remove the prepress screw.

[0064] S3. The four outer segments 130 are assembled onto the core 110 in a single row from the center to both sides using a pre-compression fixture. After assembly, thin strips of prepreg are used to fill the mesh ribs where the core 120 is joined, and the repaired area is slightly higher than the arc surface of the core 120. The pressure cylinder 140 applies a perpendicular axial pressure to the metal block through the side pressure screws. The side pressure screws are screwed in to the same length to ensure that the outer segments 130 are subjected to uniform force.

[0065] S4. After assembly, turn the prepreg material reserved when laying the lower flange reinforcement area 3 and the shell skin 1 onto the upper flange reinforcement area 3, and lay the upper flange reinforcement area 3 using the prepreg material according to the theoretical thickness of the upper flange reinforcement area 3. Install the upper cover plate 150, and evenly unplug the side pressure screws by 1-2 turns to avoid excessive pressure on the outer segment 130 by the pressure cylinder 140, which would make it difficult to install the upper cover plate 150. Insert the positioning pin 170 to prevent the upper cover plate 150 from being misaligned with the base plate 160, and screw the axial pressure screws into the threaded holes on the pre-pressure plates 180 on the upper and lower end faces of the outer segment 130, that is, the threaded holes connected to the pre-pressure set screws 190 during the partition pre-pressure molding.

[0066] S5. Screw in the axial pressure screw and the side pressure screw to apply pressure, and judge the extrusion and mold closing status through the mold closing gap observation hole and the observation gap.

[0067] like Figure 2 As shown, the side pressure screw and the axial pressure screw are fixed in the side pressure screw hole 220 and the axial pressure screw hole 230.

[0068] S6. Perform heat curing at a temperature of 110℃~150℃ for 2~4 hours.

[0069] S7. Cool to below 40℃ and demold to complete the preparation of the composite material external mesh reinforcement load-bearing cylinder.

[0070] Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0071] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A molding die for a composite material externally reinforced reinforcing steel cylinder, the composite material externally reinforced reinforcing steel cylinder comprising: The shell skin is a hollow cylindrical structure; The upper flange reinforcement area and the lower flange reinforcement area are both hollow annular structures, and are respectively located at the openings at both ends of the shell skin; A mesh reinforcement is provided on the outer wall of the shell skin. The mesh reinforcement includes circumferential reinforcement and longitudinal reinforcement. The circumferential reinforcement is evenly distributed along the axial direction of the shell skin, and the longitudinal reinforcement is parallel to the axis of the shell skin and is evenly distributed on the outer wall of the shell skin. The shell skin, the upper flange reinforcement area, the lower flange reinforcement area, and the mesh reinforcement are all integral structures made of fiber and resin, and the volume fraction of fiber in the fiber and resin composite material is 60%±3%. Each fiber and resin composite material is made up of 5 layers of fiber and resin prepreg laid at angles of 0°, 90°, +θ°, 0°, and -θ°, respectively. The axial direction of the shell skin is 0°, 30°≤θ°≤60°, and the thickness of each layer is 0.1~0.2mm. The molding die is characterized by having the following components arranged concentrically from the inside out: core, core mold, outer segment, and pressure cylinder. The core is cylindrical and is used to compress the inner wall of the composite material external mesh reinforcement support cylinder; The core mold is connected to the outer segment. The core mold includes multiple metal blocks. The metal blocks are made of aluminum alloy, and the rest of the structure is made of carbon steel. The gaps between the metal blocks are used for the extrusion molding of the mesh reinforcement. The outer segment consists of at least two pieces, and a pre-compression plate and a pre-compression ejector screw are provided around the outer segment. During the extrusion and mold closing process, the pre-compression ejector screw is used to pre-compress and form the mesh reinforcement. The pressure cylinder is used to apply pressure perpendicular to the axial direction to the outer segment. A base plate is connected to the lower end of the pressure cylinder. A first limiting structure is provided on the upper surface of the base plate to avoid excessive compression of the composite material outer mesh reinforcement support cylinder, which would cause its shell skin to become too thin. An observation gap is left at equal intervals at the connection between the base plate and the pressure cylinder to observe the distance between the composite material outer mesh reinforcement support cylinder and the base plate. An upper cover plate is connected to the upper end of the pressure cylinder. The upper cover plate is coaxially connected to the bottom plate through a positioning pin. A second limiting structure is provided on the lower surface of the upper cover plate to prevent the outer segments from tilting during the extrusion and mold closing process. Both the bottom plate and the top cover plate are provided with mold closing gap observation holes for observing the extrusion molding of the composite material external mesh reinforcement support cylinder by the molding die; The pressure cylinder has a threaded through hole on its surface, and a side pressure screw is locked to the threaded through hole. The top of the side pressure screw applies a pressure perpendicular to the axial direction to the outer segment through the threaded through hole.

2. The molding die for the composite material external mesh reinforcement load-bearing cylinder as described in claim 1, characterized in that, The outer lobes consist of four parts.

3. The molding die for the composite material external mesh reinforcement load-bearing cylinder as described in claim 1, characterized in that, The upper cover plate and the bottom plate have through holes for accommodating the positioning pins, and there are two positioning pins.

4. A method for preparing a composite material externally reinforced reinforcing steel support cylinder, characterized in that, The process of manufacturing a composite material external mesh reinforcement load-bearing cylinder using the molding die of any one of claims 1 to 3 specifically includes the following steps: S1. Fix the core to the base plate and install the lower flange reinforcement area and shell skin; S2. Lay out metal blocks according to the shape of the mesh reinforcement to be processed, and fix the core mold after laying out the metal blocks on the outer segment. Lay out the fiber and resin prepreg in groups of five layers in the gaps of the metal blocks. The laying angle of each group is 0°, 90°, +θ°, 0°, -θ°, where the axial direction of the shell skin is 0°, 30°≤θ°≤60°, and the laying thickness of each layer is 0.2mm. The fiber and resin prepreg in the gaps of the metal blocks is pre-pressed in sections by using a pre-press plate and pre-press screws. After the section pre-pressing is completed, remove the pre-press screws. S3. Assemble the core and the outer segment with the core mold fixed on it. The pressure cylinder applies a pressure perpendicular to the axial direction to the metal block through the side pressure screws. The side pressure screws are screwed in by the same length. S4. Lay out the upper flange reinforcement area, install the upper cover plate, and insert the positioning pin to prevent the upper cover plate from misaligning with the base plate; screw the axial pressure screws into the threaded holes on the pre-pressure plates at the upper and lower ends of the outer segment. S5. Screw in the axial pressure screw and the side pressure screw to apply pressure, and judge the extrusion mold closing condition through the mold closing gap observation hole and the observation gap. S6. Perform heat curing at a temperature of 110℃~150℃ for 2~4 hours. S7. Cool to below 40℃ and demold to complete the preparation of the composite material external mesh reinforcement load-bearing cylinder.

5. The method for preparing the composite material external mesh reinforcement load-bearing cylinder as described in claim 4, characterized in that, When installing the top cover, first unscrew the side pressure screws by 1-2 turns to avoid excessive pressure on the outer segments, which could make the installation of the top cover difficult.

6. The method for preparing the composite material external mesh reinforcement load-bearing cylinder as described in claim 4, characterized in that, Different mesh reinforcements can be manufactured to meet different needs by replacing the metal blocks of different thicknesses and sizes.

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