Composite material oil tank forming process method and forming mold thereof

Abstract

The composite material oil tank forming process method comprises the following steps that S1, a stripping layer is laid on the surface of a mold; s2, paving a vacuum auxiliary material layer on the stripping layer; step S3, preparing a prepreg; step S4, paving the prepreg; s5, paving a vacuum curing material layer on the surface of the prepreg; s6, demolding is conducted after hot-pressing curing, the invention further provides a forming mold which is used for achieving forming of the composite material oil tank through the composite material oil tank forming process method, the mold cost can be reduced, the forming effect and the forming quality of the composite material oil tank can be improved, and the forming quality of the composite material oil tank can be improved. According to the composite material oil tank forming process method and the forming mold thereof, the composite material oil tank can be conveniently formed, the mold cost can be reduced, and the forming effect and the forming quality of the composite material oil tank can be improved.

Description

Technical Field

[0001] The invention belongs to the field of oil tank manufacturing, and in particular relates to a composite material oil tank molding process method and a molding die thereof. Background Art

[0002] A composite fuel tank refers to a fuel tank made of composite materials (such as carbon fiber, glass fiber reinforced plastic, etc.). Composite fuel tanks have excellent properties such as light weight, high strength, and corrosion resistance, which makes composite fuel tanks widely used in aviation, automobiles, ships and other fields. They can significantly reduce the weight of the fuel tank, thereby improving the performance and fuel efficiency of the overall structure; the tensile strength and impact resistance of the fuel tank are improved, so that the fuel tank can withstand greater external pressure and impact; it also has good corrosion resistance and can effectively prevent the erosion of the material by the liquid inside the tank; the molding process of composite materials is flexible, and complex shapes of fuel tanks can be manufactured to adapt to different installation spaces and design requirements, which improves the flexibility of composite fuel tanks; composite fuel tanks have good stability in high temperature environments and are suitable for use under high temperature or extreme conditions.

[0003] The existing technology mainly adopts combined mold compression molding or RTM (Resin Transfer Molding) method to complete the production of composite fuel tanks. The design of the molding mold used is relatively complex, the mold cost is high, the molding process is difficult to control, the molding speed of the product is slow, and the cost is high. In the process of preforming the product, the control of the mold gap is difficult, and the molding equipment and production workers are required to have relatively high quality.

[0004] Therefore, we continue to develop a composite material fuel tank molding process method and its molding mold that can facilitate the molding of composite material fuel tanks, reduce mold costs, and improve the molding effect and molding quality of composite material fuel tanks. Summary of the invention

[0005] The present invention is made to solve the above problems, and aims to provide a composite material fuel tank molding process method and a molding mold thereof, which can facilitate the molding of composite material fuel tanks, reduce mold costs, and improve the molding effect and molding quality of composite material fuel tanks. In order to achieve the above objectives, the technical solution adopted by the present invention is:

[0006] The present invention provides a composite material oil tank molding process method, which has the following characteristics and comprises the following steps: step S1, laying a peeling layer on the mold surface; step S2, laying a vacuum auxiliary material layer on the peeling layer; step S3, preparing prepreg; step S4, laying the prepreg; step S5, laying a vacuum curing material layer on the prepreg surface; step S6, demoulding after hot pressing curing.

[0007] The composite material fuel tank molding process provided by the present invention may also have the following feature: in step S1, the peeling layer is made of polytetrafluoroethylene (PTFE).

[0008] The composite material fuel tank molding process provided by the present invention may also have such a feature that in step S2, the vacuum auxiliary material layer includes an isolation film, a breathable felt and a vacuum bag which are laid in sequence.

[0009] The composite material fuel tank molding process provided by the present invention may also have the following feature: in step S3, epoxy resin is impregnated into the carbon fiber material to obtain a prepreg, and the prepreg is maintained in a semi-cured state.

[0010] The composite material fuel tank molding process provided by the present invention may also have the following feature: in step S3, the prepreg obtained by impregnation is cut and divided to obtain a first prepreg sheet and a second prepreg sheet.

[0011] The composite fuel tank molding process provided by the present invention may also have the following feature: in step S4, the first prepreg sheet and the second prepreg sheet are laid on the mold, and a layer of vacuum auxiliary material is laid every two layers of prepreg.

[0012] The composite fuel tank molding process provided by the present invention may also have the following feature: in step S5, after the prepreg is laid, a vacuum-cured material layer is laid, and the vacuum-cured material layer includes a tear-off layer, an isolation film and a breathable felt.

[0013] The composite material fuel tank molding process provided by the present invention may also have the following feature: in step S6, the prepreg and mold that have been laid are hot-pressed and cured in an autoclave, and a fuel tank blank is obtained after demolding, and a hole-opening process is performed on the fuel tank blank to obtain a finished fuel tank.

[0014] The present invention also provides a molding die according to the above composite material fuel tank molding process method, which has the following characteristics: the molding die comprises a fuel tank upper mold and a fuel tank lower mold, and the fuel tank upper mold and the fuel tank lower mold are connected.

[0015] The molding die provided by the present invention may also have the following feature: the fuel tank upper die and the fuel tank lower die are made of foam material.

[0016] The technical effect of the present invention is as follows: the composite fuel tank molding process method provided by the present invention comprises the following steps: step S1, laying a peeling layer on the mold surface; step S2, laying a vacuum auxiliary material layer on the peeling layer; step S3, preparing prepreg; step S4, laying the prepreg; step S5, laying a vacuum curing material layer on the prepreg surface; step S6, demolding after hot pressing and curing. The present invention also provides a molding mold, which is used to realize the molding of the composite fuel tank through the composite fuel tank molding process provided by the present invention, which is beneficial to reducing the mold cost and improving the molding effect and molding quality of the composite fuel tank.

[0017] Therefore, the composite fuel tank molding process method and molding mold provided by the present invention can easily realize the composite fuel tank molding, can reduce the mold cost, and can improve the composite fuel tank molding effect and molding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] This specification includes the following drawings, which show the following contents:

[0019] Figure 1 is a flow chart of a composite material fuel tank forming process method in an embodiment of the present invention;

[0020] Figure 2 is a schematic structural diagram of a first prepreg sheet in an embodiment of the present invention;

[0021] Figure 3 is a schematic structural diagram of a second prepreg sheet in an embodiment of the present invention;

[0022] Figure 4 Schematic diagram of the structure of the fuel tank upper mold in an embodiment of the present invention;

[0023] Figure 5 is a structural schematic diagram of the lower mold of the fuel tank in an embodiment of the present invention;

[0024] Figure 6 Schematic diagram of the structure of a composite material fuel tank in an embodiment of the present invention.

[0025] The figures are marked as follows: first prepreg sheet 1, second prepreg sheet 2, fuel tank upper mold 3, fuel tank lower mold 4, finished fuel tank upper shell 5, finished fuel tank lower shell 6, DETAILED DESCRIPTION

[0026] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention and facilitating their implementation.

[0027] Figure 1It is a flow chart of the composite material fuel tank forming process method in the embodiment of the present invention;

[0028] As Figure 1 shown, the present invention provides a composite material fuel tank forming process method, including the following steps: Step S1, laying a release layer on the surface of the mold; Step S2, laying a vacuum-assisted material layer on the release layer; Step S3, preparing prepreg; Step S4, laying prepreg; Step S5, laying a vacuum curing material layer on the surface of the prepreg; Step S6, demolding after hot pressing and curing.

[0029] In Step S1, a release layer is laid on the surface of the mold, and the release layer is laid on the forming surface of the forming mold. The release layer is made of polytetrafluoroethylene (PTFE), which has excellent properties such as low friction, chemical resistance, high temperature resistance, and non-stickiness.

[0030] In Step S2, the vacuum-assisted material layer includes a separator film, a breather felt, and a vacuum bag laid in sequence. After the vacuum-assisted material layer is laid, it is subjected to a vacuum exhaust treatment.

[0031] Figure 2 It is a schematic structural diagram of the first prepreg sheet in the embodiment of the present invention; Figure 3 It is a schematic structural diagram of the second prepreg sheet in the embodiment of the present invention.

[0032] In Step S3, epoxy resin is impregnated into carbon fiber material to obtain prepreg, and the prepreg is kept in a semi-cured state. The impregnated prepreg is cut and divided to obtain a first prepreg sheet 1 and a second prepreg sheet 2. As Figure 2 and Figure 3 shown, the first prepreg sheet 1 is in a "cross" shape, and the second prepreg sheet 2 is in a "herb" shape, which are used for laying on different parts of the forming mold, so as to improve the laying quality and is beneficial to improving the forming effect and quality of the composite material fuel tank.

[0033] In Step S4, the first prepreg sheet 1 and the second prepreg sheet 2 are laid on the forming mold. When every two layers of prepreg are laid, a vacuum-assisted material layer is laid. The vacuum-assisted material layer includes a separator film, a breather felt, and a vacuum bag laid in sequence, so as to improve the forming effect and quality of the composite material fuel tank.

[0034] In Step S5, after the prepreg is laid, a vacuum curing material layer is laid. The vacuum curing material layer includes a tear layer, a separator film, and a breather felt, to improve

[0035] In Step S6, the laid prepreg and the mold are subjected to hot pressing and curing molding through a autoclave, and after demolding, a fuel tank blank is obtained. After the fuel tank blank is subjected to hole opening processing, a finished fuel tank is obtained.

[0036] Finally, the finished oil tank was tested non-destructively by pulse reflection method. The non-destructive test showed that the finished oil tank fully met the requirements of GJB 2895-1997A level and the finished oil tank was qualified.

[0037] Figure 4 Schematic diagram of the structure of the fuel tank upper mold in an embodiment of the present invention; Figure 5 is a structural schematic diagram of the lower mold of the fuel tank in an embodiment of the present invention; Figure 6 Schematic diagram of the structure of a composite material fuel tank in an embodiment of the present invention.

[0038] like Figure 4 and Figure 5 As shown, the present invention also provides a molding die according to the above composite material fuel tank molding process method, including a fuel tank upper mold 3 and a fuel tank lower mold 4, the fuel tank upper mold 3 and the fuel tank lower mold 4 are connected, and the fuel tank upper mold 3 and the fuel tank lower mold 4 are made of foam material, which can effectively reduce the cost of the fuel tank upper mold 3 and the fuel tank lower mold 4. The finished fuel tank obtained by the composite material fuel tank molding process method and the molding die provided by the present invention is as follows Figure 6 As shown, the finished oil tank includes a finished oil tank upper shell 5 and a finished oil tank lower shell 6, which are respectively formed by an oil tank upper mold 3 and an oil tank lower mold 4, and after obtaining the blanks of the finished oil tank upper shell 5 and the finished oil tank lower shell 6, they are spliced ​​to obtain a finished oil tank.

[0039] The first prepreg sheet 1 is laid on the bottom of the fuel tank upper mold 3 and the fuel tank lower mold 4, and the second prepreg sheet 2 is laid on the side walls of the fuel tank upper mold 3 and the fuel tank lower mold 4, thereby improving the laying effect of the prepreg.

[0040] The composite fuel tank molding process method provided by the present invention facilitates the molding of the composite fuel tank, is beneficial to reducing mold costs, is beneficial to improving the molding effect and molding quality of the composite fuel tank, and can significantly reduce the weight of the composite fuel tank, thereby improving the performance and fuel efficiency of the overall structure of the composite fuel tank; improves the tensile strength and impact resistance of the composite fuel tank, so that the composite fuel tank can withstand greater external pressure and impact; also has good corrosion resistance, and can effectively prevent the erosion of the material by the liquid inside the tank; the molding process of the composite material is flexible, and complex-shaped fuel tanks can be manufactured to adapt to different installation spaces and design requirements, thereby improving the flexibility of the composite fuel tank; the composite fuel tank has good stability in a high-temperature environment and is suitable for use under high temperature or extreme conditions.

[0041] Functions and Effects of the Embodiments

[0042] The composite fuel tank molding process method provided by the present invention comprises the following steps: step S1, laying a peeling layer on the mold surface; step S2, laying a vacuum auxiliary material layer on the peeling layer; step S3, preparing prepreg; step S4, laying the prepreg; step S5, laying a vacuum curing material layer on the prepreg surface; step S6, demolding after hot pressing and curing. The present invention also provides a molding mold, which is used to realize the molding of the composite fuel tank through the composite fuel tank molding process method provided by the present invention, which is beneficial to reducing the mold cost and improving the molding effect and molding quality of the composite fuel tank. The composite fuel tank molding process method and the molding mold provided by the present invention can conveniently realize the molding of the composite fuel tank, can reduce the mold cost, and can improve the molding effect and molding quality of the composite fuel tank.

[0043] The present invention is described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention; or the above concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A composite material fuel tank molding process, characterized in that: The following steps are involved: Step S1, laying a peeling layer on the mold surface; Step S2, laying a vacuum auxiliary material layer on the peeling layer; Step S3, preparing prepreg; Step S4, laying the prepreg; Step S5, laying a vacuum curing material layer on the surface of the prepreg; Step S6, demoulding after hot pressing curing.

2. The composite material fuel tank molding process according to claim 1, characterized in that: In the step S1, the peeling layer is made of polytetrafluoroethylene (PTFE).

3. The composite material fuel tank forming process according to claim 2, characterized in that: In the step S2, the vacuum auxiliary material layer includes an isolation film, a breathable felt and a vacuum bag which are laid in sequence.

4. The composite material fuel tank molding process according to claim 3, characterized in that: In step S3, epoxy resin is impregnated into the carbon fiber material to obtain a prepreg, and the prepreg is kept in a semi-cured state.

5. The composite material fuel tank molding process according to claim 4, characterized in that: In the step S3, the prepreg obtained by impregnation is cut and divided to obtain a first prepreg sheet and a second prepreg sheet.

6. The composite material fuel tank molding process according to claim 5, characterized in that: In step S4, the first prepreg sheet and the second prepreg sheet are laid on the mold, and a layer of vacuum auxiliary material is laid every time two layers of prepreg are laid.

7. The composite material fuel tank molding process according to claim 6, characterized in that: In the step S5, after the prepreg is laid, a vacuum curing material layer is laid, and the vacuum curing material layer includes a tear-off layer, an isolation film and an air-permeable felt.

8. The composite material fuel tank molding process according to claim 7, characterized in that: In the step S6, the prepreg and the mold after laying are heat-pressed and cured in an autoclave, and a fuel tank blank is obtained after demoulding, and a hole-drilling process is performed on the fuel tank blank to obtain a finished fuel tank.

9. A molding die for a composite fuel tank molding process according to any one of claims 1 to 8, characterized in that: It comprises an upper fuel tank mould and a lower fuel tank mould, and the upper fuel tank mould and the lower fuel tank mould are connected.

10. The molding die according to claim 9, characterized in that: The oil tank upper mold and the oil tank lower mold are made of foam material.

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