A lightweight composite panel forming process

Abstract

The application discloses a kind of lightweight composite material cabin plate forming processes, comprising the following steps: pressing inner skin;Pressing outer skin;Splicing core material: in the outer skin of the shape splicing core material on forming good outer skin, evenly smears resin on the lower surface of splicing good core material;Mold closing: from bottom to top according to the order of lower mould, outer skin, core material, inner skin, upper mould, place each part, and mold closing is carried out to upper and lower mould;Vacuum pressing: after mold closing, according to the form of mould, directly sealed by mould or assisted by vacuum bag after external application, vacuumizing is carried out to press, solidification;Forming: mold is separated, and off mould is obtained to get composite material cabin plate.The forming process provided by the application can be suitable for the lightweight forming of special-shaped cabin plate, and can ensure the lightweight of cabin plate while improving the surface quality of skin.

Description

Technical Field

[0001] This invention relates to the field of cabin panel processing technology, and more specifically, to a lightweight composite material cabin panel molding process. Background Technology

[0002] Containers used in special environments often have specific requirements, such as stealth, thermal insulation, and noise reduction. These functions cannot be achieved solely by the material of the container panels. Typically, a special core material is filled within the container panel frame, and a skin is attached to the outside to form a composite material container panel. Depending on the usage environment, the container panels are no longer limited to straight plates but are designed with irregular shapes as needed. Ordinary flat plates cannot be directly pressed and bonded, which increases the difficulty of bonding the core material and the skin. Therefore, a vacuum adsorption process was developed to address how to bond the container panel core material to the skin.

[0003] In vacuum adsorption processes, such as Figure 1 As shown, the frame and core material of the cabin plate are first assembled and placed on the matching mold 9. The core material 3 is covered with a skin, such as the outer skin 2. A vacuum bag 6 is placed over the skin. A glue injection port 10 is set on one side of the vacuum bag 6. The glue injection port 10 is connected to a resin tank 11 through a pipeline. The resin is vacuum-drawn between the skin and the core material. The resin will spread all over the surface of the core material along the glue injection port. After the resin fills the space between the skin and the core material, it is heated and cured to bond the material layer and the core material together.

[0004] However, this process results in the skin being smooth and flat on the mold surface, but not smooth on the non-mold surface. In addition, the resin will fully surround and penetrate the core material during the process, leading to excessive weight of the cabin plate. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a lightweight composite material cabin panel molding process to solve the problems of poor surface smoothness and excessive weight of the panels after molding in the prior art.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A lightweight composite material cabin panel molding process includes the following steps:

[0008] Pressing the inner skin: The inner skin is laid on the surface of the upper mold, a vacuum bag is placed on the outside of the inner skin, vacuuming and glue injection are performed, and the inner skin is pressed and cured to obtain the inner skin.

[0009] Pressing the outer skin: The outer skin is laid on the surface of the lower mold, a vacuum bag is placed over the outer skin, vacuuming and glue injection are performed, and the outer skin is pressed and cured to form the outer skin.

[0010] Splicing core material: splicing the core material on the formed outer skin according to the shape of the outer skin, evenly applying the resin on the upper and lower surfaces of the spliced core material;

[0011] Mold closing: placing each part in the order of lower mold, outer skin, core material, inner skin and upper mold from bottom to top, and closing the upper and lower molds;

[0012] Vacuum pressing: after mold closing, pressing and curing are carried out by sealing the mold directly or externally applying a vacuum bag to assist vacuumizing;

[0013] Molding: mold opening and mold releasing to obtain the composite panel.

[0014] Further, the vacuumizing time during vacuum pressing is 0.5-2h.

[0015] Further, the curing time during vacuum pressing is 5-6h.

[0016] Further, a plurality of fine hole glue channels are formed on the core material, and the fine hole glue channel is a through hole connecting the upper and lower surfaces of the core material.

[0017] Further, the core material is formed by splicing a first core material plate and a second core material plate, and a crease glue channel is formed at the splicing part of the first core material plate and the second core material plate.

[0018] Further, the resin is any one of epoxy resin, polyester resin, vinyl resin, bismaleimide resin and phenolic resin.

[0019] Further, the material of the inner skin and the outer skin is glass fiber reinforced plastic or carbon fiber, and the material of the core material is foam board.

[0020] Compared with the prior art, the present application has the following advantages:

[0021] The molding process provided by the present application can be applied to the lightweight molding of special-shaped panels. The inner and outer skins of the panel are first molded respectively, then the upper and lower molds are closed, the resin is applied on the upper and lower surfaces of the core material in advance, vacuum pressing is carried out, the vacuum suction is not connected to the external resin barrel at this time, the purpose is to make the previously applied resin more evenly distributed, and at the same time, the excess resin can be extracted, which ensures the lightweight of the panel and improves the surface quality of the skin. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiment or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other embodiments can also be obtained by those skilled in the art based on these drawings.

[0023] Figure 1 is a schematic diagram of the basic principle of vacuum suction process in the background art.

[0024] Figure 2 is a schematic diagram of the inner skin pressing in the present application.

[0025] Figure 3 is a schematic diagram of the outer skin pressing in the present application.

[0026] Figure 4 is a schematic diagram of the core material splicing in the present application.

[0027] Figure 5 is a schematic diagram of the mold closing in the present application.

[0028] Figure 6 is a schematic diagram of the lightweight composite material cabin plate after demolding in the present application.

[0029] BRIEF DESCRIPTION OF DRAWINGS

[0030] 1, inner skin; 2, outer skin; 3, core material; 31, first core material plate; 32, second core material plate;

[0031] 4, upper mold; 5, lower mold; 6, vacuum bag; 7, fine hole glue channel; 8, crease glue channel; 9, mold; 10, glue injection port; 11, resin barrel;

[0032] 100, cabin plate. DETAILED DESCRIPTION

[0033] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without the specific details set forth in this description. In other instances, well-known methods have not been described in detail in order to avoid obscuring the present application.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application.

[0036] REFERENCES Figure 6The cabin plate structure to be formed by the embodiment of the present application is shown in the figure, which is composed of an inner core material 3, an inner skin 1 laid on the upper end of the core material 3, and an outer skin 2 laid on the lower end of the core material 3. The overall structure is formed with a certain bending, that is, the cabin plate is no longer limited to a straight plate, but is designed as the special-shaped structure according to the needs (to adapt to more special environments and application scenarios, etc.). The core material 3 is formed by splicing a first core material plate 31 and a second core material plate 32, and the connecting part of the first core material plate 31 and the second core material plate 32 forms a bending structure. The material of the core material 3 can be selected from a foam plate, and the materials of the inner skin 1 and the outer skin 2 can be selected from any one of epoxy resin, polyester resin, vinyl resin, bismaleimide resin and phenolic resin.

[0037] According to the design and optimization of the cabin plate structure to be processed, the design and manufacturing of the mold are completed, that is, the corresponding upper mold 4 and lower mold 5 are obtained, which are used for subsequent process manufacturing.

[0038] As shown in the figure, the lightweight composite cabin plate forming process includes the following steps S1-S6. Figures 2 to 5

[0039] S1, pressing the inner skin 1: the inner skin 1 is laid on the surface of the upper mold 4, a vacuum bag 6 is laid outside the inner skin 1, vacuumizing and glue injection are performed, and the inner skin 1 is pressed and cured to form the inner skin 1;

[0040] S2, pressing the outer skin 2: the outer skin 2 is laid on the surface of the lower mold 5, a vacuum bag 6 is laid outside the outer skin 2, vacuumizing and glue injection are performed, and the outer skin is pressed and cured to form the outer skin;

[0041] S3, splicing the core material 3: the core material 3 is spliced on the formed outer skin 2 according to the shape of the outer skin 2, and resin is evenly applied to the upper and lower surfaces of the spliced core material 3;

[0042] S4, mold closing: the parts are placed in the order of the lower mold 5, the outer skin 2, the core material 3, the inner skin 1 and the upper mold 4 from bottom to top, and the upper and lower molds are closed;

[0043] S5, vacuum pressing: after the mold is closed, the mold is directly sealed or a vacuum bag is laid outside to assist vacuumizing for pressing and curing;

[0044] S6, forming: the mold is opened, and the composite cabin plate 100 is obtained.

[0045] It should be noted that in the embodiment of the present application, the step S1 and the step S2 can be exchanged in sequence, or the two steps are performed simultaneously.

[0046] ​In step S5, after the mold is closed, a sealed vacuum can be directly formed through the upper mold and the lower mold, or a vacuum bag can be used to assist in vacuumizing and pressing the upper mold and the lower mold; that is, the upper mold and the lower mold can directly cooperate to form a sealed structure, or a sealing ring structure can be arranged between the upper mold and the lower mold to achieve better sealing conditions and thus improve the vacuumizing effect; or in some cases, a vacuum bag can be used to assist in vacuumizing and pressing the upper mold and the lower mold.

[0047] At the same time, in the actual construction process, the resin glue solution can also be more evenly distributed during the vacuumizing process in step S5, and the excess resin can be extracted. Of course, this step can also be omitted according to the actual operation conditions; that is, if the resin is thinly coated (or the resin is relatively thick), the resin can be directly pressed and vacuumized, and the glue can also be extracted.

[0048] Taking the pressing of the inner skin as an example, the steps of the existing conventional vacuum bag pressing forming technology can be followed. Generally, a release agent needs to be coated on the upper mold 4 in advance to facilitate subsequent demolding. A flow guide net can also be laid on the inner skin after the inner skin is laid, so that the resin can more effectively penetrate the surface and the bottom layer of the inner skin, ensuring that the fibers and the resin are fully infiltrated, thereby improving the overall performance of the inner skin. At the same time, the space net structure of the flow guide net can also help to remove the residual gas in the liquid resin and the laying structure of the inner skin, which is helpful to the porosity of the inner skin after forming and improves the compactness and mechanical properties thereof.

[0049] In order to further ensure the uniformity of the resin in the inner skin 1, the vacuum degree during vacuumizing should be no less than 80 Kpa. Sufficient vacuum degree can promote the flow and penetration of the resin, while reducing air bubbles. In addition, the viscosity of the resin is controlled to be 0.1-0.3 Pa.s, which is beneficial to the flow and penetration of the resin.

[0050] Of course, the pressing and forming of the outer skin 2 can also be set in the same way. The materials of the inner skin 1 and the outer skin 2 are glass fiber reinforced plastic or carbon fiber, and multiple layers can be laid at the same time according to the required thickness.

[0051] In some preferred embodiments, when the skin (the inner skin 1 and / or the outer skin 2) is processed, a support member with a certain structural strength can be further arranged outside the vacuum bag. The support member covers the entire vacuum bag, so that a chamber that can also be vacuumized is formed between the support member and the vacuum bag.

[0052] At this time, the vacuum bag inside, the chamber between the vacuum bag and the support can be simultaneously subjected to the vacuumizing operation, so as to avoid being pressed by the external atmospheric pressure in the internal vacuumizing process, so that the gas can be better sucked from the material layer of the skin, so as to realize the effect of further reducing the bubble rate; then, under the condition that the vacuum bag inside is kept in the vacuum state, the chamber between the external support and the vacuum bag is pressurized to about atmospheric pressure, so that the internal skin can be pressed and cured under the action of atmospheric pressure; the resin in the obtained skin is more uniformly distributed, and the bubble rate is lower.

[0053] In the embodiment of the present application, the forming method of the skin in steps S1 and S2 can also adopt the hot press tank pressing mode, but the cost is higher, therefore, in the embodiment of the present application, the vacuum bag pressing forming mode is preferred.

[0054] In the vacuum pressing, the vacuumizing time is controlled to be 0.5-2h; the curing time is 5-8h. In the vacuumizing time of the embodiment of the present application, the internal air and volatile matter can be sufficiently discharged, so as to ensure that these gases are effectively discharged, reduce the generation of pores and bubbles, and thus improve the compactness and strength of the product; in the curing, the heating rate can be controlled to be 2℃ / min-3℃ / min, after heating to 60℃-180℃, the cooling to below 35℃ can be completed at the speed of 0.1-0.4℃ / min; the better control of the curing time and the heating rate can prevent the generation of internal stress in the curing process, ensure the stability and mechanical properties of the final cabin plate; and also can avoid the local overheating or incomplete curing, and ensure the uniformity of the curing.

[0055] Further, in some preferred embodiments, as shown in Figure 5 For the products with higher structural strength requirements, the amount of resin applied by hand is less than that of the vacuum adsorption coating, and the stress on the cabin plate in the use process is not necessarily uniform, so there is a risk of glue opening when the resin is applied by hand. In order to avoid this glue opening, a glue channel is preferably provided in the core material 3, which is a fine hole connecting the upper and lower surfaces of the core material 3, i.e. a fine hole glue channel 7. When the glue is applied, the glue is injected into the glue channel, and after vacuum pressing, the glue channel directly connects the inner skin 1 and the outer skin 2, and the glue in the glue channel directly forms a "glue nail" after curing, which significantly improves the adhesion between the skin and the core material. The number of fine hole glue channels 7 is set according to the size of the cabin plate, which is not specifically limited here.

[0056] Alternatively, for the special-shaped cabin plate, the joint crease of the core material 3 is a natural glue channel, i.e. a crease glue channel 8, which does not need to be separately provided, and fills the bending gap between the core material 3 and the skeleton to enhance the internal structural strength of the cabin plate.

[0057] The forming process provided by the application can be suitable for lightweight forming of the special-shaped cabin plate, the inner and outer skins of the cabin plate are formed step by step, then the upper and lower molds are combined, the resin is smeared on the upper and lower surfaces of the core material in advance, vacuum pressing is carried out, at this time, the vacuum suction is not connected with the external resin barrel, the purpose is to make the previously smeared resin be distributed more uniformly, and at the same time, the excess resin can be extracted, avoiding the problem that the excess resin fully surrounds the core material and penetrates into the core material in the integral forming process, causing the cabin plate to be overweight, that is, the process provided by the application ensures the lightweight of the cabin plate while improving the surface quality of the skin.

[0058] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0059] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrated; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0060] In the description of the present application, the description of the terms "the present embodiment", "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in at least one embodiment or example. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the present application and the features of the different embodiments or examples without contradiction.

[0061] In addition, the terms "first", "second", etc. are used only for the purpose of description, and should not be understood as indicating or implying relative importance or a specific number of the technical features indicated. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0062] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement and simple improvement made on the essential content of the present application shall be included in the protection scope of the present application.

Claims

1. A lightweight composite material cabin panel molding process, characterized in that, Includes the following steps: Pressing the inner skin: The inner skin is laid on the surface of the upper mold, a vacuum bag is placed on the outside of the inner skin, vacuuming and glue injection are performed, and the inner skin is pressed and cured to obtain the inner skin. Pressing the outer skin: The outer skin is laid on the surface of the lower mold, a vacuum bag is placed over the outer skin, vacuuming and glue injection are performed, and the outer skin is pressed and cured to form the outer skin. Core material splicing: Splice the core material on the molded outer skin according to the shape of the outer skin, and apply resin evenly to the upper and lower surfaces of the spliced ​​core material; Mold closing: Place the parts in the following order from bottom to top: lower mold, outer skin, core material, inner skin, and upper mold, and then close the upper and lower molds. Vacuum pressing: After the mold is closed, the mold is sealed directly or a vacuum bag is applied to assist in vacuuming for pressing and curing, depending on the mold type. During vacuum pressing, the vacuum suction is not connected to the external resin tank. The purpose is to distribute the previously coated resin more evenly and to remove excess resin at the same time. Molding: Mold separation, mold release, to obtain composite material cabin panels; The core material has multiple fine-pore adhesive channels, which are through holes connecting the upper and lower surfaces of the core material.

2. The lightweight composite material cabin panel molding process according to claim 1, characterized in that, During vacuum pressing, the vacuuming time is 0.5-2 hours.

3. The lightweight composite material cabin panel molding process according to claim 1, characterized in that, When vacuum pressing, the curing time is 5-6 hours.

4. The lightweight composite material cabin panel molding process according to claim 1, characterized in that, The core material is formed by splicing a first core material board and a second core material board, and a crease glue groove is formed at the splice of the first core material board and the second core material board.

5. The lightweight composite material cabin panel molding process according to claim 1, characterized in that, The resin is any one of epoxy resin, polyester resin, vinyl resin, bismaleimide resin, and phenolic resin.

6. The lightweight composite material cabin panel molding process according to claim 1, characterized in that, The inner and outer skins are made of fiberglass or carbon fiber; the core material is made of foam board.

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