One-step forming method of array type small-diameter co-flange carbon fiber launching tube

Abstract

The application discloses a one-time forming method of an array type small-diameter common-flange carbon fiber launching cylinder, and steps are as follows: designing the structure of the launching cylinder; designing a forming die and a tool; designing a parting layer design of the array type small-diameter common-flange carbon fiber launching cylinder; and forming the array type small-diameter common-flange carbon fiber launching cylinder. The wedge-shaped pin is used in multiple places, so that the pressure transmission is uniform in the forming process of the complex structure; compared with other preparation processes, the cylinder body is directly formed in one time without machining, bonding and sealing; and the trapezoidal mouth pre-impregnated cloth is used at the flange, so that the flange plate and the cylinder body are connected and fastened through the occlusion lamination, and the integration is realized in the structure.

Description

Technical Field

[0001] The present invention belongs to the technical field of preparation of light conventional equipment system launch device components, and relates to a one-step molding method for an array-type small-diameter common flange carbon fiber launch tube. Background Art

[0002] Modern warfare demands lightweight conventional equipment systems with high mobility, high rate of fire, and high power. Conventional metal design, based on conventional materials, results in significant weight, while equipment systems have limited space and payload. To ensure equipment flexibility, reduce overall weight, and improve payload and system performance, lightweight launch systems are required to achieve strategic objectives. The launch system is the device that enables a product to reach its target and strike, and is generally composed of components such as the launch barrel, end cap, firing mechanism, and sights.

[0003] The launch tube is part of the launch system. During launch, the barrel rifling guides the product out of the launch tube, and its posture is controlled by the barrel rifling. During the launch process, the product is subjected to instantaneous strong impact loads, high temperature, and high pressure, causing the equipment system to generate extremely complex vibrations and heat radiation. The matrix interface of carbon fiber composite materials has a strong vibration absorption effect. Compared with ferrous metals, it has better comprehensive properties such as strength, rigidity, and toughness. In addition, it is resistant to high temperatures, ablation, has high specific strength, and has a large specific modulus, making it an ideal material for launch tubes. Existing launch tubes are assembled in a modular manner. That is, multiple launch tubes and connecting plates are first separately formed, and threaded holes or rivet holes are machined into the connecting plates. The launch tube structural components are assembled and combined by screwing or riveting and gluing. The preparation process is cumbersome, and the coordination relationship of the positioning of the inner rifling during assembly is complex. Factors such as stress concentration at the screw holes or rivet holes seriously affect the stability and sealing of the product. Summary of the Invention

[0004] (1) Purpose of the invention

[0005] The purpose of the present invention is to provide a one-time molding method for an array-type small-diameter common flange carbon fiber launch tube, utilizing the designability of carbon fiber composite materials, the flexibility of mold design, the convenience of molding methods, etc., to avoid the complicated process of punching and gluing after the single tube is molded, improve production efficiency and product integrity, and at the same time meet the multiple launch requirements of light conventional equipment launch systems.

[0006] (2) Technical solution

[0007] In order to solve the above technical problems, the present invention provides a one-step molding method for an array-type small-diameter common flange carbon fiber launch tube, comprising the following steps:

[0008] (1) Design the structure of the launch tube: Design an array-type small-diameter common flange carbon fiber launch tube, perform finite element analysis on the array-type small-diameter common flange carbon fiber launch tube, and obtain the geometric model of the array-type small-diameter common flange carbon fiber launch tube; the designed array-type small-diameter common flange carbon fiber launch tube has a mounting hole in the center and multiple launch tube bodies are evenly distributed around the circumference.

[0009] (2) Design of molding mold and tooling: Design a molding mold based on the structural characteristics of the array-type small-diameter common flange carbon fiber launch tube. The mold is divided into a core mold, a mold sleeve, an inner mold, an outer mold, and a flange molding metal plate; design a demoulding tooling to obtain a molding mold for an array-type small-diameter common flange carbon fiber launch tube.

[0010] (3) Design of the layup of array-type small-diameter common flange carbon fiber launch tubes: The carbon fiber / epoxy prepreg is impregnated by hot melt method, and the quasi-isotropic design of the layup of array-type small-diameter common flange carbon fiber launch tubes is carried out. The prepreg is cut to obtain the prepreg used for the molding of array-type small-diameter common flange carbon fiber launch tubes.

[0011] (4) Forming of array-type small-diameter common flange carbon fiber launch tube: the core mold is covered with prepreg cloth, the inner mold and mold sleeve are covered with prepreg cloth, vacuum pre-pressed, combined molding mold, array-type small-diameter common flange carbon fiber launch tube is formed and cured, demolded, and post-processed to obtain an array-type small-diameter common flange carbon fiber launch tube.

[0012] Furthermore, the design of the array-type small-diameter common flange carbon fiber launch tube in step (1) is carried out by surveying and designing the single-tube diameter, length, wall thickness, rifling style, flange connection size, etc. of the launch tube combined by screwing and gluing.

[0013] Further preferably, screws, sealants, and connecting devices are removed during the design process, and carbon fiber composite materials are used to supplement the missing parts at these locations.

[0014] Further preferably, the carbon fiber composite material is an intermediate prepreg formed by pre-impregnation of a reinforcement carbon fiber fabric (twill, satin, plain) and a resin matrix (epoxy resin, phenolic resin, bismaleimide resin, etc.), and the prepreg used in the patent of the present invention is a twill carbon fiber / epoxy prepreg (hereinafter "prepreg" can be used instead of "carbon fiber / epoxy prepreg").

[0015] Furthermore, step (1) performs finite element analysis on the array-type small-diameter co-flange carbon fiber launch tube, and uses computer software (the software used in the patent of this invention is ABAQUS, and other software can also be analyzed, such as UG, CATIA, CREO, etc.) to analyze the force of the geometric model of the array-type small-diameter co-flange carbon fiber launch tube. The launch tube structure is optimized according to the design results to obtain the geometric model of the array-type small-diameter co-flange carbon fiber launch tube.

[0016] Furthermore, step (2) designs a forming mold based on the external structural characteristics of the array-type small-diameter common flange carbon fiber launch tube, and the mold is divided into a core mold, a mold sleeve, an inner mold, an outer mold, and a flange forming metal disk.

[0017] Further preferably, there are six evenly distributed metal hollow cylinders inside the core mold, and a demolding taper is designed along the length direction of the non-flange disk. The taper is designed to be 1 / 1000 of the overall length of the launch tube. The six metal hollow cylinders are detachable, and the outer surface of the metal hollow cylinders has protruding rifling. The launch tube is fixed and combined by a circular chassis during molding. After the six metal hollow cylinders are assembled, the six metal hollow cylinders are fixed separately on one side of the core mold by the locating pins of the circular chassis, and the other side of the core mold is fixed using a plum blossom disk combination with a long axis to facilitate the laying of prepreg cloth.

[0018] Further preferably, the mold sleeve is divided into two parts, the left and right parts, the interior of the left and right mold sleeves are designed according to the outer surface of the launch tube, and the exterior of the left and right mold sleeves are designed as a wedge-shaped style of a cylindrical segment, which is convenient for evenly applying pressure through the outer mold mating surface segment when closing the mold. The mating surfaces of the two parts of the left and right mold sleeves are chamfered, and four locating pins are left in the left and right mold sleeves. Wedge grooves and glue flow grooves for flange-formed metal inner disks are left at the inner and outer molds of the left and right mold sleeves, and guide grooves are left at the closing mold of the left and right mold sleeves.

[0019] Further preferably, the inner mold is a three-petal combination mold, which is similar to a plum blossom shape after combination. The outer surface of the inner mold after combination follows the inner surface of the launch tube. After the inner mold is combined, the inner ring pressure device is wedge-shaped. After the wedge-shaped pin is inserted, it is convenient for the left and right mold sleeves to apply pressure during molding.

[0020] More preferably, the outer mold is designed as an upper and lower mold, fixed to the press (threaded holes can also be opened in the outer mold and pressurized by screws, but the present invention adopts a press to apply pressure). The outer mold is designed with a circle of annular electric heating holes and equipped with thermocouple holes to form a uniform temperature field during the molding of the launch tube. The inner surfaces of the upper and lower outer molds follow the outer surface of the mold sleeve.

[0021] Further preferably, the flange-shaped metal inner plate is a wedge-shaped hexagonal upper and lower plate, which is convenient for pressurization.

[0022] Furthermore, the demoulding tooling in step (2) is demoulded using a drawing machine of a hydraulic mechanical device. The demoulding tooling is used to pull out the core mold while ejecting the launch cylinder, with a guide rail connecting the middle, a corresponding gear rack provided on the guide rail, and a servo motor provided on the gear rack.

[0023] Furthermore, in step (3), the carbon fiber / epoxy prepreg is impregnated by a hot melt method, the epoxy resin is heated and melted, and the thickness of the adhesive film is calculated according to the surface density and resin content of the prepreg (the epoxy resin content of the prepreg used in the present invention is 40±3%). After the adhesive film is formed, it is impregnated with the carbon fiber fabric, and an isolation film is attached and rolled up to obtain the carbon fiber / epoxy prepreg.

[0024] Furthermore, in step (3), the array-type small-diameter common flange carbon fiber launch tube ply is quasi-isotropically designed and parted, the carbon fiber / epoxy prepreg is parted according to [(0° / 90°)(45° / -45°)], the flange is designed by opening a trapezoidal opening and alternatingly laying annular prepreg, the parted prepreg is designed by circumferential butt jointing when laying on a single tube body, the length of the prepreg after parting is controlled so that the butt joints of the prepreg are evenly distributed on the tube body, thereby ensuring uniform mechanical strength and thickness of the launch tube after molding.

[0025] Further preferably, the carbon fiber / epoxy prepreg is divided into [(0° / 90°)(45° / -45°)] types, which are distinguished in such a way that the radial fiber tow parallel to the prepreg is 0° and the angle rotated counterclockwise is positive.

[0026] Furthermore, in step (3), the prepreg is cut according to the designed pattern using an automatic cloth cutting machine, and the cut prepregs are numbered.

[0027] Furthermore, in step (4), the core mold is assembled and then placed on a support frame for prepreg draping molding, and draped separately according to the parting pattern of the prepreg. When every six metal hollow cylinders are draped with one layer, a layer of prepreg with a trapezoidal opening is draped on the flange forming circular chassis, so that the trapezoidal opening prepreg at the flange and the prepreg on the metal hollow cylinder are cross-distributed. According to the thickness of the flange, the annular cloth is inserted in batches during the draping process, and the metal cylinder rifling is compacted according to the shape during the draping process.

[0028] Furthermore, in step (4), the inner mold and mold sleeve are covered with prepreg cloth, and two layers of prepreg cloth are laid on the inner mold and the mold sleeve, and a scraper is used to smooth them. Before laying, the inner mold and the mold sleeve can also be heated to 40°C to 50°C to facilitate laying.

[0029] Furthermore, the vacuum pre-pressing in step (4) requires vacuum pre-pressing every time two layers of prepreg are laid, and the inner mold and mold sleeve also need to be vacuum compacted after the laying is completed.

[0030] Further preferably, after vacuuming, a porous membrane and a breathable felt are sequentially laid on the surface of the product after making a vacuum bag, and the whole is placed in place and sealed with a sealant.

[0031] More preferably, the vacuuming should ensure that the pressure in the vacuum bag is below -0.085 MPa, and the vacuuming time is more than 15 minutes.

[0032] Furthermore, in the combined molding mold described in step (4), the plum blossom disk with the long axis is removed, the core mold is placed in the mold sleeve, and the three-petal inner mold is sequentially placed in the gaps between the six launch tubes of the core mold after the prepreg is laid, and a wedge pin is inserted into the center of the three-petal inner mold; the flange-molded metal inner disk is assembled and placed in the left mold sleeve as a whole, the right mold sleeve is closed according to the positioning pin, and the lower outer mold is placed on the press, and the electric heating tube and thermocouple are inserted according to the reserved electric heating holes, and the mold is closed.

[0033] Furthermore, in step (4), the array-type small-diameter common flange carbon fiber launch tube is formed and cured, and the curing temperature is controlled by a temperature control cabinet next to the press. The specific parameters are: heating to 85°C in 50min~70min, keeping warm at 85°C for 40min, heating from 85°C to 100°C in 15min, applying contact pressure (2MPa~3MPa), keeping warm at 100°C for 30min, and then heating from 100°C to 125°C~130°C in 25min, during which the contact pressure is increased to (5MPa~6MPa) and (7MPa~8MPa) twice, and then keeping warm and pressurizing at 125°C~130°C for 90min. After the pressurization is completed, the mold gap is ≤0.2mm, and then the power is turned off and cooled naturally.

[0034] Furthermore, in step (4), the demoulding is carried out by naturally cooling the mold to below 60°C, removing the mold sleeve and the flange forming inner disk, placing the core mold as a whole on the demoulding tooling, and using a hydraulic mechanical drawing machine for demoulding. The tube stripping machine runs slowly and at a uniform speed to separate the metal hollow tube and the launch tube product.

[0035] Furthermore, in the post-processing described in step (4), the edges of the launch tube after demoulding are polished and the joints are cleaned to obtain an array-type small-diameter common flange carbon fiber launch tube.

[0036] (3) Beneficial effects

[0037] The above technical solution provides a one-time molding method for array-type small-diameter common flange carbon fiber launch tubes. It innovatively uses wedge pins in multiple places to ensure uniform pressure transmission during the molding of complex structural parts. Compared with other preparation processes, the launch tube body is non-machined, non-bonded, and non-sealed, and can be directly molded in one step. The use of trapezoidal prepreg at the flange allows the flange and the tube body to be fastened through interlocking laminations to achieve structural integration. The use of carbon fiber / epoxy composite materials replaces the original screws and colloids, eliminating the influence of the interface between different materials in the composite material on the bonding strength of the product. The non-autoclave molding method is adopted to save the molding cost of the launch tube, which is in line with the production concept of reducing costs and increasing efficiency. Through the cooperation of the combination mold, the molding method is reliable, highly repeatable, and the process coordination relationship is reasonable. The curing characteristics of epoxy resin are fully utilized, and the gradient molding temperature level is set. The excellent process characteristics of the prepreg are utilized to improve the mechanical and thermal properties of the parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 Schematic diagram of the array-type small-diameter common flange carbon fiber launch tube structure.

[0039] Figure 2 Schematic diagram of the core mold structure; a is the core mold structure, b is the schematic diagram of the plum blossom disk structure, and c is the metal hollow cylinder.

[0040] Figure 3 Schematic diagram of a single mold sleeve structure.

[0041] Figure 4 Schematic diagram of the inner mold structure.

[0042] Figure 5 Schematic diagram of the outer mold section and flange-formed metal inner disk section structure.

[0043] Figure 6 Schematic diagram of the trapezoidal prepreg at the flange. DETAILED DESCRIPTION

[0044] In order to make the purpose, content and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below with reference to the accompanying drawings and examples.

[0045] The one-step molding method of the array-type small-diameter common flange carbon fiber launch tube in this embodiment includes the following steps:

[0046] (1) Design the structure of the launch tube

[0047] The surveying and design is carried out based on the diameter, length, wall thickness, rifling pattern and flange connection dimensions of the launch tube combined with screw connection and adhesive connection. The screws, sealants and connection devices are removed in the software, and the strength design of carbon fiber composite materials is used to compensate for the position here. Figure 1As shown, the array-type small-diameter common flange carbon fiber launch tube 1 is draped and molded using twill carbon fiber / epoxy prepreg. Finite element analysis is performed on the array-type small-diameter common flange carbon fiber launch tube 1. Computer software (the software used in the present invention is ABAQUS, and other software can also be analyzed, such as UG, CATIA, CREO, etc.) is used to perform a force analysis on the geometric model of the array-type small-diameter common flange carbon fiber launch tube 1 under the working conditions. The launch tube structure is optimized based on the deformation and stability results of the product to obtain the final geometric model of the array-type small-diameter common flange carbon fiber launch tube 1. Finite element analysis first discretizes and meshes the launch tube 1 model, uses carbon fiber / epoxy prepreg to prepare mechanical specimens, tests mechanical properties such as tensile strength, bending strength, and impact shear strength, inputs the mechanical property parameters of the tested carbon fiber composite material, sets the boundary condition simulation and load simulation according to the use conditions of the launch tube, and analyzes the flange 2 connection thickness and launch tube wall thickness of the array-type small-diameter common flange carbon fiber launch tube to see whether the calculation results meet the design requirements and usage requirements. Based on the corresponding stress lines and deformation amounts of various parts of the launch tube's geometric model, the weak parts of the launch tube design are thickened until the launch tube structure meets the requirements.

[0048] (2) Molding mold and tooling design

[0049] Based on Figure 1 The array type small diameter common flange carbon fiber launch tube 1 shown in the figure is designed with the shape and structure characteristics of the molding mold, which is divided into the following Figure 2 The core mold shown, such as Figure 3 The mold set shown, such as Figure 4 The inner mold shown, such as Figure 5 The outer mold and flanged formed metal inner disc are shown.

[0050] Among them Figure 2 The interior of the core mold shown is divided into six evenly distributed metal hollow cylinders 3. The demoulding taper is designed along the length direction of the non-flange disk, wherein the taper of the metal hollow cylinder 3 is designed to be 1 / 1000 of the overall length of the launch tube, which is convenient for demoulding. The six metal hollow cylinders 3 are detachable, and there are supporting core shafts in the middle. The outer surface of the metal hollow cylinder 3 has protruding rifling 5, which is convenient for forming the rifling inside the launch tube. The launch tube is fixed and assembled by the circular chassis 4 during molding. The circular chassis 4 is the molding part of the launch tube flange 2. The six metal hollow cylinders 3 are fixed on one side by the positioning pins of the circular chassis 4 to ensure that the order of the inner rifling of each launch tube is consistent. The other side of the core mold is combined and fixed with a plum blossom disk (7) with a long axis and the previously assembled core mold circular chassis. The metal long axis 6 extends out of the circular chassis 4 to facilitate the laying of prepreg. In summary, as described above, Figure 2 The core mold shown is composed of six metal hollow cylinders 3, a circular base plate 4, a plum blossom plate 7 with a long axis, and a positioning pin 8.

[0051] like Figure 3 The mold sleeve 9 shown includes two parts, the left and right mold sleeves 9 are arranged according to the following Figure 1 The outer surface area of ​​the launch tube 1 shown is designed as shown in FIG. Figure 4 The inner mold (12) shown in the figure is the barrel style of the launch tube after the mold is closed. The outer design of the left and right mold sleeves 9 is a wedge-shaped style with a cylindrical section, which is convenient for closing the mold by Figure 5 Pressure is evenly applied to the mating surface of the outer mold shown, and the joint surfaces of the left and right mold sleeves 9 are chamfered to reserve extrusion capacity for the prepreg at the mold joint, thereby improving the appearance quality of the launch tube and ensuring the overall mechanical structure of the launch tube 1. The left and right mold sleeves 9 are respectively provided with four positioning pins to facilitate mutual coordination and positioning during molding. The inner mold 12 of the left and right mold sleeves 9 is provided with wedge grooves and glue flow grooves for the flange molding metal inner disk 10 to facilitate pressurization and excess glue flow during flange 2 molding. A guide groove is left at the mold joint of the left and right mold sleeves 9 to facilitate later vacuum pre-compression and glue circulation during molding, compensate for the glue-deficient area inside the launch tube, and improve the quality of the launch tube.

[0052] like Figure 4 The inner mold 12 shown is a three-petal combination mold style, which is similar to a plum blossom shape after combination. The outer surface of the inner mold 12 after combination follows the inner surface of the launch tube 1. After the inner mold 12 is combined, the inner ring pressure device is designed to be wedge-shaped. After the wedge-shaped pin 13 is inserted, it is convenient to pressurize during molding. When the launch tube 1 is molded, the wedge-shaped pin 13 applies pressure from the left and right mold sleeves 9, so that the inner mold 12 is gradually corrected during the molding process.

[0053] like Figure 5 The outer mold shown is designed as an upper and lower mold, fixed to the press (it is also possible to open a threaded hole in the outer mold and use a screw to apply pressure, and then go to the press to form the shape. The present invention uses a press to apply pressure). The outer mold is designed with a circle of annular electric heating holes 14 and equipped with thermocouple holes to achieve a uniform temperature field during the molding of the launch tube 1. The inner surface of the upper and lower outer molds follows the outer surface of the mold sleeve 9, but the wedge is about 5mm smaller than the mold sleeve 9, which facilitates the effective transmission of pressure after the press is applied.

[0054] like Figure 5 The flange-shaped metal inner plate 15 shown is a wedge-shaped hexagonal upper and lower plate, which accompanies the flange of the die sleeve 9 to facilitate pressure transmission through the inclined surface.

[0055] The demoulding tooling uses a drawing machine with a hydraulic mechanical device for demoulding. The demoulding tooling pulls out the outer side of the circular chassis 4 of the core mold while simultaneously ejecting six launch cylinders. The drawing machine is connected by a guide rail in the middle, and a corresponding gear rack is provided on the guide rail, and a servo motor is provided on the gear rack.

[0056] (3) Design of split-layer ply for array-type small-diameter common flange carbon fiber launch tube

[0057] The epoxy resin is heated and melted, and the thickness of the adhesive film is calculated according to the surface density and resin content of the prepreg (the epoxy resin content of the prepreg used in the present invention is 40±3%). After the adhesive film is made, it is impregnated with the carbon fiber fabric, and the isolation film is attached and rolled up to obtain the carbon fiber / epoxy prepreg. At the same time, the ply of the array-type small-diameter common flange carbon fiber launch tube is quasi-isotropically designed and parted. The carbon fiber / epoxy prepreg is parallel to the radial fiber bundle on the prepreg at 0°, and the counterclockwise rotation angle is positive. The parting is performed according to [(0° / 90°)(45° / -45°)], and the flange is taken as follows. Figure 6 The trapezoidal prepreg (16) at the flange shown and the annular prepreg are laid alternately to form an interlocking stacking design to enhance the connection strength. The prepregs of the split type are designed to be butted in an annular direction when laid on a single barrel. The length of each prepreg after splitting is controlled so that the prepreg seams are evenly distributed annularly on the barrel, ensuring the mechanical strength of the launch tube after molding and the uniformity of the launch tube thickness. An automatic cloth cutting machine is used to cut according to the designed pattern, and the cut prepregs are numbered to prevent confusion during laying.

[0058] (4) Forming of array-type small-diameter common flange carbon fiber launch tubes

[0059] will be as Figure 2 After the core mold is assembled, it is placed on a support frame and coated with carbon fiber / epoxy prepreg according to the pattern. For every six metal hollow cylinders 3, a layer of trapezoidal prepreg 16 is applied to the flange, ensuring that the trapezoidal prepreg 16 and the prepreg on the metal hollow cylinder 3 are interlaced. Ring-shaped prepregs are inserted into the flange in stages, depending on the thickness of the flange 2. During the coating process, the rifling grooves 5 on the metal hollow cylinder are compacted according to the shape. Depending on the vacuum conditions, 3mm wide, 90°-oriented thin strips of prepreg can be used to compensate for the rifling area, facilitating surface smoothing when subsequently coating the reinforced areas of the launch tube. Additional prepreg is added to areas requiring reinforcement based on the launch tube's geometry. Vacuum pre-compacting is performed after every two layers of prepreg are applied. Finally, the two layers are applied to the inner mold 12 and mold sleeve 9, and smoothed using a scraper. The inner mold and mold sleeve can be heated to 40°C to 50°C before coating. Vacuum pre-compacting is performed after coating.

[0060] After making the vacuum bag, the porous membrane and breathable felt are laid on the surface of the product in sequence, and the whole is placed in and sealed with sealant. The vacuum bag should be kept below -0.085MPa during vacuuming, and the vacuuming time should be at least 15 minutes.

[0061] After the paving is completed, the plum blossom disk 7 with the long mandrel is removed. Figure 2The core mold shown is placed in the mold sleeve 9, the three-petal inner mold 12 is placed in sequence, the wedge pin 13 is inserted, the flange forming metal inner disk 15 is assembled, and the whole is placed in the left mold sleeve. The right mold sleeve is closed according to the positioning pin, and the lower outer mold is placed on the press. The electric heating tube and thermocouple are inserted according to the reserved electric heating hole 14, and the mold is closed. The present invention uses a temperature control cabinet next to the press to control the curing temperature, and other temperature control equipment can also be used for pressurization. The specific curing parameters are: heating to 85°C in 50min~70min, keeping warm at 85°C for 40min, heating from 85°C to 100°C in 15min, applying contact pressure (2MPa~3MPa), keeping warm at 100°C for 30min, and then heating from 100°C to 125°C~130°C in 25min, during which the contact pressure is increased to (5MPa~6MPa) and (7MPa~8MPa) twice, and then keeping warm and pressurizing at 125°C~130°C for 90min. After pressurization is completed, Figure 5 The outer mold joint gap shown is ≤0.2mm, then the power is turned off and naturally cooled to below 60℃, the mold is opened, the mold sleeve 9 and the flange forming metal inner plate 15 are taken off, and the mold is opened. Figure 2 The core mold as shown is placed on the demoulding tooling, and the hydraulic mechanical device is used to pull the mold out. The tube stripping machine runs slowly and evenly to remove the metal hollow tube 3 and the launch tube product. Grind the burrs of the launch tube and clean the seams to obtain the following Figure 1 An array-type small-diameter common flange carbon fiber launch tube is shown.

[0062] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A one-step molding method for an array-type small-diameter common flange carbon fiber launch tube, characterized in that: The following steps are involved: (1) Design the structure of the launch tube: Design an array-type small-diameter common flange carbon fiber launch tube, perform finite element analysis on the array-type small-diameter common flange carbon fiber launch tube, and obtain a geometric model of the array-type small-diameter common flange carbon fiber launch tube; the designed array-type small-diameter common flange carbon fiber launch tube has a mounting hole in the center and multiple launch tube bodies evenly distributed around the circumference; (2) Design of molding mold and tooling: Design a molding mold based on the structural characteristics of the array-type small-diameter common flange carbon fiber launch tube. The mold is divided into a core mold, a mold sleeve, an inner mold, an outer mold, and a flange forming metal plate. Design a demoulding tooling to obtain a molding mold for an array-type small-diameter common flange carbon fiber launch tube. (3) Design of the layup of array-type small-diameter common flange carbon fiber launch tubes: The carbon fiber / epoxy prepreg is impregnated by hot melt method, and the quasi-isotropic design of the layup of the array-type small-diameter common flange carbon fiber launch tube is carried out. The prepreg is cut to obtain the prepreg used for the formation of the array-type small-diameter common flange carbon fiber launch tube; (4) Forming of array-type small-diameter common flange carbon fiber launch tube: the core mold is prepreg-assisted and formed, the inner mold and mold sleeve are covered with prepreg, vacuum pre-pressed, and the molding mold is combined. The array-type small-diameter common flange carbon fiber launch tube is formed and cured, demolded, and post-processed to obtain an array-type small-diameter common flange carbon fiber launch tube.

2. The one-step molding method of the array-type small-diameter common flange carbon fiber launch tube according to claim 1, characterized in that: In step (1), the design of the array-type small-diameter common-flange carbon fiber launch tube is a combination of screw connection and gluing, and the single-tube diameter, length, wall thickness, rifling style, and flange connection size of the launch tube are surveyed and designed; during the design process, the screws, sealants, and connecting devices are removed, and carbon fiber composite materials are used to supplement the missing positions here; the carbon fiber composite material is an intermediate prepreg formed by pre-impregnation of reinforcement carbon fiber fabric and resin matrix; finite element analysis is performed on the array-type small-diameter common-flange carbon fiber launch tube, and computer software is used to analyze the force of the geometric model of the array-type small-diameter common-flange carbon fiber launch tube. The launch tube structure is optimized according to the design results to obtain the geometric model of the array-type small-diameter common-flange carbon fiber launch tube.

3. The one-step molding method of the array-type small-diameter common flange carbon fiber launch tube according to claim 2, characterized in that: In step (2), a forming mold is designed according to the external structural characteristics of the array-type small-diameter common flange carbon fiber launch tube, and the mold is divided into a core mold, a mold sleeve, an inner mold, an outer mold, and a flange forming metal disk; The inside of the core mold is six evenly distributed metal hollow cylinders. The demoulding taper is designed along the length direction of the non-flange disk. The taper is designed to be 1 / 1000 of the overall length of the launch tube. The six metal hollow cylinders are detachable. There are protruding rifling on the outer surface of the metal hollow cylinder. The launch tube is fixed and assembled by a circular chassis during molding. After the six metal hollow cylinders are assembled, the six metal hollow cylinders are fixed separately on one side of the core mold by the locating pins of the circular chassis, and the other side of the core mold is fixed with a plum blossom disk combination with a long axis; the mold sleeve is divided into left and right parts. The interior of the left and right mold sleeves is designed according to the outer surface of the launch tube, and the exterior of the left and right mold sleeves is designed as a wedge-shaped style of a cylindrical segment, which is convenient for passing through the outer mold when closing the mold. Pressure is applied evenly to the mating surface section, and the mating surfaces of the left and right mold sleeves are chamfered. Four locating pins are left in the left and right mold sleeves. Wedge grooves and glue flow grooves for the flange-forming metal inner disk are left at the inner and outer molds of the left and right mold sleeves, and guide grooves are left at the mold closing point of the left and right mold sleeves; the inner mold is a three-petal combination mold, and the outer surface of the inner mold after assembly follows the inner surface of the launch tube. After the inner mold is assembled, the inner ring pressure device is wedge-shaped. After the wedge-shaped pin is inserted, pressure is applied by the left and right mold sleeves during molding; the outer mold is designed as an upper and lower mold, fixed on the press, and a circle of annular electric heating holes is designed on the outer mold, equipped with thermocouple holes, and the inner surfaces of the upper and lower outer molds follow the outer surface of the mold sleeve; the flange-forming metal inner disk is a wedge-shaped hexagonal upper and lower disk.

4. The one-step molding method of the array-type small-diameter common flange carbon fiber launch tube according to claim 3 is characterized in that: In step (2), demoulding is performed using a drawing machine of a hydraulic mechanical device. The demoulding tooling is used to pull out the core mold while ejecting the launch cylinder, with a guide rail in the middle, a corresponding gear rack provided on the guide rail, and a servo motor provided on the gear rack.

5. The one-step molding method of the array-type small-diameter common flange carbon fiber launch tube according to claim 4, characterized in that: In step (3), the carbon fiber / epoxy prepreg is impregnated by hot melt method, the epoxy resin is heated and melted, and the thickness of the adhesive film is calculated according to the surface density and resin content of the prepreg. After the adhesive film is formed, it is impregnated with the carbon fiber fabric, and an isolation film is attached and rolled up to obtain the carbon fiber / epoxy prepreg.

6. The one-step molding method of the array-type small-diameter common flange carbon fiber launch tube according to claim 5, characterized in that: In step (3), the array-type small-diameter common flange carbon fiber launch tube ply is quasi-isotropically designed and parted, the carbon fiber / epoxy prepreg is parted according to [(0° / 90°)(45° / -45°)], the flange is designed by opening a trapezoidal opening and alternatingly laying annular prepreg, the parted prepreg is designed by circumferential butt jointing when laying on a single barrel, and the length of the prepreg after parting is controlled so that the butt joints of the prepreg are evenly distributed on the barrel.

7. The one-step molding method of the array-type small-diameter common flange carbon fiber launch tube according to claim 6, characterized in that: In step (4), the core mold prepreg auxiliary covering molding is placed on the support frame after the core mold is assembled and covered separately according to the parting of the prepreg. When every six metal hollow cylinders are covered with a layer, a layer of prepreg with a trapezoidal opening is covered on the flange forming circular chassis, so that the trapezoidal opening prepreg at the flange and the prepreg on the metal hollow cylinder are cross-distributed. According to the thickness of the flange, the annular cloth is inserted in batches during the covering process, and the metal cylinder rifling is compacted according to the shape during the auxiliary covering process.

8. The one-step molding method of the array-type small-diameter common flange carbon fiber launch tube according to claim 7, characterized in that: In step (4), the inner mold and mold sleeve are covered with prepreg cloth, and two layers of prepreg cloth are laid on the inner mold and mold sleeve, and a scraper is used to flatten them. The inner mold and mold sleeve are heated to 40°C to 50°C before laying; the vacuum pre-pressing is performed for each two layers of prepreg cloth laid, and the inner mold and mold sleeve are vacuumed and compacted after the laying is completed; the vacuuming is performed after making a vacuum bag, and a porous membrane and a breathable felt are laid on the surface of the product in sequence, and the whole is placed in and sealed with sealant; the pressure in the vacuum bag is below -0.085MPa during vacuuming, and the vacuuming time is more than 15 minutes.

9. The one-step molding method of the array-type small-diameter common flange carbon fiber launch tube according to claim 8, characterized in that: In step (4), when assembling the forming mold, the plum blossom disk with the long axis is removed, the core mold is placed in the mold sleeve, and the three-petal inner mold is sequentially placed in the gaps between the six launch tubes of the core mold after the prepreg is laid, and a wedge pin is inserted into the center of the three-petal inner mold; the flange-forming metal inner disk is assembled and placed in the left mold sleeve as a whole, the right mold sleeve is closed according to the positioning pin, and the lower outer mold is placed on the press, and the electric heating tube and thermocouple are inserted according to the reserved electric heating holes, and the mold is closed.

10. The one-step molding method of the array-type small-diameter common flange carbon fiber launch tube according to claim 9, characterized in that: In step (4), the array type small diameter common flange carbon fiber launch tube is formed and cured, and the curing temperature is controlled by a temperature control cabinet next to the press. The parameters are: heating to 85°C in 50min~70min, keeping warm at 85°C for 40min, heating from 85°C to 100°C in 15min, applying a contact pressure of 2MPa~3MPa, keeping warm at 100°C for 30min, and then heating from 100°C to 125°C~130°C in 25min, during which the contact pressure is increased to 5MPa~6MPa and 7MPa~8MPa twice. MPa, and then keep it warm and pressurized at 125℃~130℃ for 90min. After the pressurization is completed, the mold gap is ≤0.2mm, and then the power is turned off and it is cooled naturally. When demolding, the mold is naturally cooled to below 60℃, the mold is removed, the mold sleeve and the flange forming inner disk are removed, and the core mold is placed on the demolding tooling. The hydraulic mechanical drawing machine is used for demolding, and the tube stripping machine runs slowly and evenly to separate the metal hollow tube and the launch tube product. During post-processing, the launch tube after demolding is polished and the joints are cleaned to obtain an array-type small-diameter common flange carbon fiber launch tube.

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