A method for forming a cylindrical aerogel thermal insulation component

Abstract

This application discloses a method for forming a cylindrical aerogel insulation component, which relates to the field of aerogel preparation technology and includes the following steps: 1) designing and producing a core mold that is consistent with the shape of the inner surface of the aerogel insulation component; 2) needle-punching a fiber preform on the core mold so that the outer surface of the core mold is consistent with the outer surface of the aerogel insulation component; 3) sealing the core mold; 4) placing the core mold in an open bag, which is then opened into a barrel-shaped container, and a weight is placed on the core mold in the bag; 5) injecting glue into the open bag and container; 6) after the glue injection is completed, sealing the open bag, allowing it to stand and gel; 7) removing the open bag from the container, disassembling the open bag and core mold to obtain a fiber-gel composite; 8) aging the fiber-gel composite and drying it to obtain the target aerogel insulation component. This method is suitable for the development of cylindrical aerogel insulation components with complex shapes, saving mold costs, shortening the development cycle, and improving efficiency.

Description

Technical Field

[0001] The present application relates to the technical field of aerogel preparation, and in particular to a method for forming a cylindrical aerogel thermal insulation component. Background Art

[0002] Aerogel is a nanoporous, lightweight material with excellent thermal insulation properties. It has been widely used, especially in fields such as aerospace. At present, the molding of aerogel insulation parts mainly adopts the mold molding method. For aerogel insulation parts with complex shapes, mold molding is often used to prepare blanks, and then mechanical processing is used to process the complex shapes. For cylindrical aerogel insulation parts with complex shapes, it is necessary to increase block splicing, that is, first use mold molding to prepare block blanks, then machine the shape, and finally combine and splice the cylindrical insulation parts. The disadvantages of the above mold method are: a large number of molds are required, the production cost is high, and the block splicing inevitably has splicing seams, which poses a risk of reduced thermal insulation performance at the seams. Summary of the Invention

[0003] The purpose of this application is to provide a method for forming a cylindrical aerogel thermal insulation component, so as to solve the technical problems of complex process and high production cost in the production process of cylindrical aerogel to a certain extent.

[0004] To solve the above technical problems, this application adopts the following technical solutions:

[0005] The present invention provides a method for forming a cylindrical aerogel thermal insulation component, comprising the following steps:

[0006] 1) designing and manufacturing a core mold having a shape consistent with the inner surface of the aerogel thermal insulation component;

[0007] 2) needle-punching the fiber preform on the core mold so that the outer surface of the core mold is consistent with the outer surface shape of the aerogel thermal insulation component;

[0008] 3) Seal the core mold;

[0009] 4) Place the core mold into an open bag, then place the open bag into a barrel-shaped container, and place a weight on the core mold in the bag;

[0010] 5) Inject glue into open bags and containers;

[0011] 6) After the glue injection is completed, seal the bag and let it stand to gel;

[0012] 7) taking the open bag out of the container, disassembling the open bag and the core mold to obtain a fiber-gel composite;

[0013] 8) The fiber-gel composite is subjected to aging treatment and dried to obtain the target aerogel thermal insulation component.

[0014] In some embodiments, the core mold is a detachable wooden core mold.

[0015] In some embodiments, the sealing of the core mold specifically includes: using sealant to seal the seams at the inner wall of the core mold, installing end covers at both ends of the core mold, and using sealant to seal the seams between the end covers and the core mold.

[0016] In some embodiments, the sealant is glass tape, aluminum foil tape, or solid tape.

[0017] In some embodiments, the open bag is a plastic bag or a rubber bag.

[0018] In some embodiments, the glue injection process specifically includes: injecting the prepared sol into the open bag, the sol entering the pores of the fiber preform, and at the same time adding a fluid pressurized medium between the open bag and the barrel gap, and using the pressure difference between the sol and the pressurized medium to make the four sides of the open bag fit with the fiber preform.

[0019] In some embodiments, the fluid pressure medium is sand, wet gel powder or liquid material that has a higher density than sol and is easy to fill.

[0020] In some embodiments, the disassembling of the open bag and the core mold specifically includes: after taking off the open bag, removing the sealant at the seam of the end cover, removing the end cover, and then removing the sealant at the seam of the splicing block on the inner wall of the core mold, disassembling the core mold, and obtaining a fiber gel composite.

[0021] In some embodiments, the aging treatment specifically includes placing the fiber-gel complex in an aging solution for aging.

[0022] In some embodiments, the drying method is alcohol supercritical drying, carbon dioxide supercritical drying or atmospheric pressure drying.

[0023] It can be seen from the above technical solution that this application has at least the following advantages and positive effects:

[0024] The present invention discloses a method for forming a cylindrical aerogel insulation component. By employing a one-step, integrated molding process, this method achieves zero seams for the aerogel insulation component, effectively preventing the risk of reduced insulation performance at seams. This method is widely applicable to cylindrical, conical, polygonal straight, polygonal tapered, or other irregular cylindrical shapes, with either uniform or unequal wall thicknesses, thus enhancing process flexibility. This method is suitable for the development of complex cylindrical aerogel insulation components, saving mold costs, shortening development cycles, and improving development efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 is a process flow chart of a method for forming a cylindrical aerogel thermal insulation member according to an embodiment;

[0027] Figure 2 Schematic diagram of the processing structure of a molding method of a cylindrical aerogel thermal insulation component according to an embodiment.

[0028] The accompanying drawings are described as follows: 1. container; 2. fluid pressurized medium; 3. sol; 4. open bag; 5. fiber preform; 6. core mold. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0030] In the description of this application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0031] The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the technical features being referred to. Thus, a feature identified as "first," "second," or "third" may explicitly or implicitly include one or more of such features. Throughout the description of this application, unless otherwise specified, "plurality" means two or more.

[0032] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "connected," "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0033] Example 1.

[0034] See also Figure 1 and Figure 2 .

[0035] Figure 1 and Figure 2 1 is a process flow chart and structural schematic diagram of a method for forming a cylindrical aerogel thermal insulation member in an embodiment of the present application. As shown in the figure, the method includes the following steps:

[0036] 1) Making a detachable core mold 6 according to the shape of the inner surface of the aerogel insulation component;

[0037] Specifically, the core mold 6 is a wooden core mold, which is low in cost and can be reused.

[0038] 2) Needle punching the reinforcing fibers into a fiber preform 5 on a core mold 6 according to the outer surface shape of the aerogel thermal insulation component;

[0039] Specifically, the reinforcing fiber is one or a mixture of alkali-free fiber, aluminum silicate, rock wool, high silica, quartz, mullite, and alumina fiber felt.

[0040] 3) sealing the core mold 6;

[0041] Specifically, the steps for sealing the core mold 6 are as follows: using sealant to seal the seams on the inner wall of the core mold 6 , installing end covers at both ends of the core mold 6 , and using sealant to seal the seams between the end covers and the core mold 6 .

[0042] In this embodiment, the sealant is a glass tape, an aluminum foil tape or a solid tape. The sealant seals the assembly seam of the wooden detachable core mold 6 to prevent the glue from entering the core mold 6 and wasting the glue.

[0043] 4) Place the core mold 6 into the open bag 4, then open the open bag 4 into the barrel-shaped container 1, and place a weight on the core mold 6 in the bag;

[0044] Specifically, the open bag 4 is a plastic bag or a rubber bag, and is most preferably an elastic rubber bag.

[0045] 5) performing glue injection on the open bag 4 and the container 1;

[0046] Specifically, the prepared sol 3 is injected into the open bag 4, and the sol 3 enters the pores of the fiber preform 5. At the same time, a fluid pressurized medium 2 is added between the open bag 4 and the barrel gap. The pressure difference between the sol 3 and the pressurized medium is used to make the four sides of the open bag 4 fit the fiber preform 5. By using the fluid pressurized medium 2 instead of complex mold molding, the mold cost can be significantly reduced.

[0047] In this embodiment, the fluid pressurized medium 2 is sand, wet gel powder or liquid material that has a higher density than the sol 3 and is easy to fill.

[0048] 6) After the glue injection is completed, seal the open bag 4 and let the gel stand;

[0049] 7) Taking the open bag 4 out of the container 1, disassembling the open bag 4 and the core mold 6 to obtain a fiber-gel composite;

[0050] Specifically, after taking off the open bag 4, remove the sealant at the seam of the end cover, remove the end cover, and then remove the sealant at the seam of the splicing blocks on the inner wall of the core mold 6, disassemble the core mold 6, and obtain the fiber-gel composite.

[0051] 8) The fiber-gel composite is subjected to aging treatment and dried to obtain the target aerogel thermal insulation component.

[0052] Specifically, the aging treatment is to place the fiber-gel composite in an aging liquid for aging; the drying method is alcohol supercritical drying, carbon dioxide supercritical drying or normal pressure drying.

[0053] In this embodiment, the aerogel used in the aerogel thermal insulation component is one of silicon dioxide, aluminum oxide, zirconium oxide, or a composite aerogel, and the sol 3 in step 5) is the sol used for the aerogel condensation.

[0054] In this embodiment, the cylindrical aerogel can be cylindrical, conical, polygonal straight, polygonal conical or other irregular cylindrical shapes, and the cylindrical wall of the cylindrical aerogel can be of equal thickness or unequal thickness. In the specific implementation process of this embodiment, it is necessary to produce conical cylindrical high-silica fiber-added silica aerogel insulation parts with unequal wall thickness. First, a detachable wooden core mold is designed according to the shape and size of the target product, and then a high-silica fiber preform is formed on the wooden core mold by needle punching; the joints on the inner wall of the core mold are sealed with sealing strips, and the end caps at both ends of the core mold are installed and the joints are sealed with sealing strips; the core mold and the fiber preform are placed in an elastic rubber open bag, and the opening is placed upward in a barrel-shaped container, and a weight is placed on the core mold to prevent the core mold with the fiber preform from floating up under the action of buoyancy when injecting glue; silica sol is prepared, and fine sand with a density greater than silica sol is selected as the pressure medium; the prepared silica sol is injected into the open bag In the process, silica sol enters the pores of the fiber preform. Fine sand is added between the open bag and the barrel. The bag is then lifted, and the pressure difference between the silica sol and the pressurized medium sand is used to conform the bag to the fiber preform. After the glue is injected, the bag's opening is sealed and the gel is allowed to stand. After removing the surrounding fine sand, the open bag containing the fiber-gel composite and core mold is removed from the barrel. After removing the open bag, the sealant at the end cap joint is removed. The end cap is then removed, and the sealant at the joints of the core mold's inner wall is removed. The core mold is disassembled to obtain the fiber-gel composite. After being treated in an aging solution, it is dried through supercritical carbon dioxide to obtain the target product, a conical cylindrical high-silica fiber-enhanced silica aerogel thermal insulation component. This cylindrical aerogel thermal insulation component is directly formed as a whole, without joints or the need for a metal forming mold, saving over 90% in costs.

[0055] Example 2.

[0056] During the specific implementation of this embodiment, it is necessary to produce cylindrical mullite fiber with equal wall thickness and add alumina aerogel insulation parts. First, a detachable wooden core mold is designed according to the shape and size of the target product, and then a mullite fiber preform is formed by needle punching on the wooden core mold; the joints on the inner wall of the core mold are sealed with aluminum foil sealing tape, and the end caps at both ends of the core mold are installed and the joints are sealed with aluminum foil sealing tape; the core mold and the fiber preform are placed together in a plastic open bag, and the opening is placed upward in a barrel-shaped container, and a weight is placed on the core mold to prevent the core mold with the fiber preform from floating up under the action of buoyancy when the glue is injected; an alumina sol is prepared, and a silicon dioxide wet gel powder with a density greater than that of the alumina sol is selected as the pressure medium; the prepared alumina sol is injected into the open bag, and the sol is put into the The process involves injecting the glue into the pores of the fiber preform, adding silica wet gel powder between the open bag and the gap between the barrel, lifting the open bag, and utilizing the pressure difference between the alumina sol and the silica wet gel powder to conform the bag to the fiber preform. After the glue injection is complete, the bag's opening is sealed and the gel is allowed to stand. After removing the silica wet gel powder from the periphery, the open bag containing the fiber-gel composite and the core mold is removed from the barrel. After removing the open bag, the aluminum foil sealing tape at the seam of the end cap is removed, the end cap is removed, and then the aluminum foil sealing tape at the seam of the splicing blocks on the inner wall of the core mold is removed. The core mold is disassembled to obtain the fiber-gel composite. After being treated in an aging solution, the composite is supercritically dried with ethanol to obtain the target product, a cylindrical mullite fiber-added alumina aerogel thermal insulation component with equal wall thickness. This cylindrical aerogel thermal insulation component is directly integrally formed without seams or the need for metal forming molds, saving over 90% in costs.

[0057] Example 3.

[0058] In the specific implementation process of this embodiment, a polygonal straight quartz fiber with equal wall thickness is produced by adding silica aerogel insulation. First, a detachable wooden core mold is designed according to the shape and size of the target product, and then a quartz fiber preform is formed on the wooden core mold by needle punching; the seams on the inner wall of the core mold are sealed with glass tape, and end caps are installed at both ends of the core mold and the seams are sealed with glass tape; the core mold together with the fiber preform is placed in an elastic rubber open bag, and the opening is placed upward in a barrel-shaped container, and a weight is placed on the core mold to prevent the core mold with the fiber preform from floating up under the action of buoyancy during glue injection; silica sol is prepared, and fine sand with a density greater than that of silica sol is selected as the pressure medium; the prepared silica sol is injected into the open bag, and the silica Silica sol is introduced into the pores of the fiber preform. Fine sand is then added between the open bag and the barrel. The bag is then lifted, and the pressure differential between the silica sol and the pressurized sand allows the bag to conform to the fiber preform. After the glue is injected, the bag's opening is sealed and the gel is allowed to settle. After removing the surrounding fine sand, the open bag containing the fiber-gel composite and core mold is removed from the barrel. After removing the open bag, the sealant at the end cap joints is removed. The end caps are then removed, and the sealant at the joints between the inner wall of the core mold is removed. The core mold is then disassembled to obtain the fiber-gel composite. After treatment in an aging solution, the composite is supercritically dried with ethanol to obtain a polygonal, straight-tube quartz fiber-added silica aerogel thermal insulation component of the same wall thickness as the target product. This cylindrical aerogel thermal insulation component is directly formed as a whole, without joints or the need for metal forming molds, saving over 90% in costs.

[0059] It can be seen from the above technical solution that this application has at least the following advantages and positive effects:

[0060] A molding method for a cylindrical aerogel insulation component in the present application can achieve zero-seam aerogel insulation components by adopting an overall one-time molding method, effectively preventing the risk of reduced insulation performance at the joints. It can be widely applied to cylindrical, conical, polygonal straight, polygonal conical or other irregular cylinders, and the cylinder wall thickness can be equal or unequal, thereby improving process flexibility.

[0061] This method is suitable for the development of complex cylindrical aerogel insulation products, saving mold costs, shortening the development cycle, and improving development efficiency. The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited to this. Any changes or substitutions that can be easily conceived by any person skilled in the art within the technical scope disclosed in this invention should be covered by the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope of protection of the claims.

Claims

1. A method for forming a cylindrical aerogel thermal insulation component, characterized in that: The following steps are involved: 1) designing and manufacturing a core mold having a shape consistent with the inner surface of the aerogel thermal insulation component; 2) needle-punching the fiber preform on the core mold so that the outer surface of the core mold is consistent with the outer surface shape of the aerogel thermal insulation component; 3) Seal the core mold; 4) Place the core mold into an open bag, then place the open bag into a barrel-shaped container, and place a weight on the core mold in the bag; 5) Inject glue into open bags and containers; 6) After the glue injection is completed, seal the bag and let it stand to gel; 7) taking the open bag out of the container, disassembling the open bag and the core mold to obtain a fiber-gel composite; 8) subjecting the fiber-gel composite to an aging treatment and drying to obtain a target aerogel thermal insulation component; The glue injection process specifically includes: injecting the prepared sol into the open bag, the sol entering the pores of the fiber preform, and at the same time adding a fluid pressurized medium between the open bag and the barrel gap, and utilizing the pressure difference between the sol and the pressurized medium to make the four sides of the open bag fit the fiber preform.

2. The method for forming a cylindrical aerogel thermal insulation component according to claim 1, characterized in that: The core mold is a detachable wooden core mold.

3. The method for forming a cylindrical aerogel thermal insulation component according to claim 1, characterized in that: The sealing of the core mold specifically includes: using sealant to seal the seams of the inner wall of the core mold, installing end covers at both ends of the core mold, and using sealant to seal the seams between the end covers and the core mold.

4. The method for forming a cylindrical aerogel thermal insulation component according to claim 3, characterized in that: The sealant is glass tape, aluminum foil tape or solid tape.

5. The method for forming a cylindrical aerogel thermal insulation component according to claim 1, characterized in that: The open bag is a plastic bag or a rubber bag.

6. The method for forming a cylindrical aerogel thermal insulation component according to claim 1, characterized in that: The fluid pressure-filling medium is sand, wet gel powder or liquid material which has a higher density than the sol and is easy to fill.

7. The method for forming a cylindrical aerogel thermal insulation member according to claim 3, characterized in that: The disassembling of the open bag and the core mold specifically includes: after taking off the open bag, removing the sealant at the seam of the end cover, removing the end cover, and then removing the sealant at the seam of the splicing block on the inner wall of the core mold, disassembling the core mold, and obtaining the fiber gel composite.

8. The method for forming a cylindrical aerogel thermal insulation component according to claim 1, characterized in that: The aging treatment specifically includes: placing the fiber-gel complex in an aging solution for aging.

9. The method for forming a cylindrical aerogel thermal insulation component according to claim 3, characterized in that: The drying method is alcohol supercritical drying, carbon dioxide supercritical drying or normal pressure drying.

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