High-reliability rigid-flexible sealing connection structure capable of being disassembled and assembled repeatedly

Abstract

The invention discloses a high-reliability rigid-flexible sealing connection structure capable of being disassembled and assembled repeatedly, and belongs to the technical field of structural design. The structure comprises a flexible film structure, a sealing ring and a fastener, the flexible film structure is a composite layer, a pressure-bearing layer, an airtight layer and a flame-retardant layer are sequentially arranged from the inside of a metal cabin to the outside of the metal cabin, and all the layers are independently connected with the metal cabin. The metal cabin is provided with a circle of evenly-distributed hooks and a ring frame in the ring direction, the ring frame is located above the hooks, a sealing groove and a plurality of screw holes are formed in the end face of the ring frame, the airtight layer and the ring frame are pressed tightly through a sealing ring placed in the sealing groove, and the screw holes, the airtight layer and the flame-retardant layer are connected through fasteners. And the metal cabin and the airtight layer as well as the metal cabin and the flame-retardant layer are connected. The device can be repeatedly disassembled and assembled, is high in reliability, and is particularly suitable for a large-size rigid-flexible mixed sealed cabin structure.

Description

Technical Field

[0001] The invention relates to a highly reliable rigid-flexible sealing connection structure capable of being disassembled and assembled multiple times, belonging to the technical field of structural design. Background Art

[0002] As space exploration missions become more complex and exploration targets become more distant, the need for lightweight aircraft becomes more urgent. Using flexible film sealing structures to replace metal sealed cabin structures is an effective way to reduce weight and has broad application prospects in the future.

[0003] Flexible sealing structures can be applied to fully flexible sealed cabin structures and rigid-flexible hybrid sealed cabin structures. Due to openings and equipment connections, fully flexible sealed cabin structures inevitably have transitional connections with rigid structures, while rigid-flexible hybrid sealed cabin structures are a more efficient structural form in certain exploration missions, and rigid structures and flexibility require sealed connections. Rigid-flexible connection structures must have long life, highly reliable load-bearing and sealing performance, and these connections are prone to become weak links due to sudden changes in stiffness and long-term wear, which are the key points and difficulties in the design of flexible sealed cabin structures.

[0004] Chinese patent CN104058103A discloses a rigid-flexible connection structure for a flexible inflatable deployment structure of a spacecraft, in which a double-pass O-ring is added between the rigid-flexible structure to achieve an airtight connection. The document "Analysis of Sealing Performance of O-rings in Flexible Cabins" introduces a rigid-flexible sealed connection structure. The technical solutions proposed by these two methods are to achieve sealing by locally generating a large sealing contact stress after the O-ring is compressed. The disadvantage is that the airtight membrane of the connection structure may slip from the compressed position under the action of the internal pressure load, making the bearing and sealing functions ineffective.

[0005] Patent CN106287101B discloses a method for bonding a solid rocket engine nozzle to a flexible plugging cover and a sealing tool. The document "Inflatable Structures Technology Handbook" introduces a method of bonding a flexible film to a metal part with an adhesive to achieve a rigid-flexible airtight connection. These two methods bond the rigid-flexible structure at the connection position to ensure airtightness, and at the same time prevent the flexible airtight film from slipping at the connection position. The shortcomings of these two methods are that once bonded, the structure cannot be disassembled, the structure cannot be repaired or replaced, and the sealing performance is greatly affected by the bonding process and is difficult to accurately control. Summary of the invention

[0006] The technical problem solved by the present invention is: to overcome the shortcomings of the prior art and propose a highly reliable rigid-flexible sealed connection structure that can be disassembled and assembled multiple times, which has highly reliable load-bearing and sealing functions, can be disassembled and assembled repeatedly, and is particularly suitable for large-size rigid-flexible hybrid sealed cabin structures.

[0007] The technical solution of the present invention is:

[0008] A highly reliable rigid-flexible sealing connection structure that can be disassembled and assembled multiple times, used to connect metal cabins, including a flexible membrane structure, a sealing ring, and a fastener;

[0009] The flexible membrane structure is a composite layer, which is composed of a pressure-bearing layer, an airtight layer and a flame-retardant layer from the inside to the outside of the metal cabin, and each layer is independently connected to the metal cabin; the pressure-bearing layer is used to support the airtight layer and bear and transmit the internal pressure load, the airtight layer is used for sealing, and the flame-retardant layer is used to flame-retard the metal cabin;

[0010] The metal cabin is evenly provided with a number of hooks along the circumferential direction, the hooks serve as interfaces between the metal cabin and the pressure-bearing layer, and the pressure-bearing layer is hung on the hooks; the metal cabin is provided with a ring frame along the circumferential direction, and the ring frame is located above the hooks; a sealing groove and a number of evenly distributed screw holes are provided on the end face of the ring frame, the airtight layer and the ring frame are pressed tightly by a sealing ring placed in the sealing groove, and the screw holes are connected to the airtight layer and the flame-retardant layer by fasteners, so as to realize the connection between the metal cabin and the airtight layer, and the metal cabin and the flame-retardant layer.

[0011] Furthermore, the pressure-bearing layer is a membrane structure made of nylon-polyurethane coated fabric by cutting and heat-sealing, and a number of hanging holes are evenly arranged on the outer periphery. The shape, size and distribution of the hanging holes are the same as the shape, size and distribution of the hooks. The hanging holes correspond to the hooks one by one and are tightly fitted so that the pressure-bearing layer can be hung on each hook.

[0012] Furthermore, a screw hole is provided on each hook for installing an anti-slip screw to prevent the pressure-bearing layer from slipping out of the hook. One end of the anti-slip screw is flush with the side of the hook, and the other end is not allowed to hit the metal cabin wall.

[0013] Furthermore, the airtight layer is formed by bonding an airtight film and a second bonding ring. The airtight film is a membrane structure made of a polyurethane film by cutting and heat-sealing. The second bonding ring is a circular plate structure. The second bonding ring and the ring frame are compressed and sealed by a sealing ring. The second bonding ring is provided with a plurality of nail holes evenly arranged in the annular direction. The number and distribution of the nail holes are the same as the number and distribution of the screw holes on the ring frame. Fasteners are passed through the nail holes and the corresponding screw holes to achieve a fixed connection between the airtight layer and the metal cabin.

[0014] Furthermore, the material of the second adhesive ring is preferably a lightweight aluminum alloy, a fiber-reinforced composite laminate or plastic, and one side of the second adhesive ring pressing the sealing ring is a sealing surface with a roughness less than 1.6.

[0015] Furthermore, the surface of the ring frame facing the outside of the cabin is designed to be a slope, and the roughness of each surface of the sealing groove is less than 1.6.

[0016] Furthermore, the flame retardant layer includes a flame retardant cloth and a first bonding ring. The first bonding ring is a circular plate structure, and the outer periphery of the flame retardant cloth is bonded to the first bonding ring. The first bonding ring is evenly provided with a plurality of nail holes along the annular direction, and the number and distribution of the nail holes are the same as the number and distribution of the screw holes. Fasteners are passed through the nail holes and the corresponding screw holes to achieve a fixed connection between the airtight layer and the metal cabin. The material of the first bonding ring is preferably a lightweight aluminum alloy, a fiber-reinforced composite laminate or plastic.

[0017] Furthermore, a plurality of soft pads are arranged between the pressure-bearing layer, the airtight layer and the bulkhead of the metal cabin to fill the gaps between the ring frame, the metal bulkhead, the hook, the airtight layer and the pressure-bearing layer to support and protect the airtight layer.

[0018] Furthermore, the soft pad is made of light foam or sponge, and is divided into multiple sections along the metal cabin bulkhead; an embedded groove is processed on the soft pad, and is embedded between the ring frame and the hook through a tight fit.

[0019] A method for assembling a high-reliability rigid-flexible sealing connection structure, comprising:

[0020] Step 1: Install the sealing ring into the sealing groove;

[0021] Step 2: Set quadrant marks on the pressure-bearing layer, airtight layer, flame-retardant layer, and metal cabin, align the quadrant marks on the pressure-bearing layer with the quadrant marks on the metal cabin, and hang the hanging holes of the pressure-bearing layer on the hooks of the metal cabin;

[0022] Step 3: Install the anti-slip screw. One end of the anti-slip screw should be flush with the side of the hook, and the other end should not touch the metal cabin wall.

[0023] Step 4: Install multiple soft pads;

[0024] Step 5: Align the quadrant mark on the airtight layer with the quadrant mark on the metal cabin, place the second bonding ring with the airtight film on top of the ring frame and the sealing ring, and install at least 4 fasteners to temporarily fix the airtight layer;

[0025] Step 6: Align the quadrant mark on the flame retardant layer with the quadrant mark on the metal cabin, and place the first bonding ring with the flame retardant cloth on top of the second bonding ring;

[0026] Step 7: Remove the fasteners that temporarily fix the airtight layer, and reinstall the fasteners to connect the screw holes with the airtight layer and flame retardant layer. The fasteners are installed diagonally, and pre-tightening force is applied at multiple levels to make the product evenly stressed. Seal the screw heads with glue during the last installation.

[0027] The advantages of the present invention compared with the prior art are:

[0028] (1) The connection between each functional layer (pressure-bearing layer, airtight layer and flame-retardant layer) and the metal cabin in the rigid-flexible connection structure proposed by the present invention is independent of each other, and the connection reliability is high. The pressure-bearing layer is hung on the cabin hook through the hanging hole, which is a multi-point dispersed connection. Under the action of internal pressure, each point evenly disperses and transfers the pressure-bearing layer load to the metal cabin, and the joint can withstand a large load; the connection function between the airtight layer and the metal cabin is airtight, and does not bear the internal pressure load. The airtight layer is bonded to the bonding ring, which is the first sealing link. The bonding ring and the cabin ring frame are pressed by a sealing ring, which is the second sealing link. Both sealing links have highly reliable sealing performance and make the connection between the airtight layer and the cabin detachable; the flame-retardant layer is bonded to another bonding ring and connected to the metal cabin ring frame through fasteners. Soft pads are filled between the airtight layer, the pressure-bearing layer and the metal cabin to support and protect the airtight membrane. Each layer is independently connected to independently realize different functions, and the connection reliability is high.

[0029] (2) The rigid-flexible connection structure proposed by the present invention can be repeatedly disassembled and assembled. The pressure-bearing layer is hooked with the metal cabin, and the airtight layer and the flame-retardant layer are mechanically connected to the metal cabin through an adhesive ring. The connection of each functional layer can be repeatedly disassembled and assembled, and the operation is convenient.

[0030] (3) The rigid-flexible connection structure proposed in the present invention is lightweight and is particularly suitable for large-sized rigid-flexible hybrid sealed cabins. A relatively weak adhesive ring can achieve a reliable airtight connection, which can avoid the weight increase caused by a connection flange with greater rigidity; the hook and the metal cabin are integrated, and no transition structure is required, saving structural weight. For large-sized rigid-flexible hybrid sealed cabin structures, the weight advantage of the rigid-flexible connection structure proposed in the present invention is more significant. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0032] Figure 1 This is an assembly relationship diagram of a rigid-flexible connection structure according to an embodiment of the present invention;

[0033] FIG. 2( a ) is a schematic diagram of the entire metal cabin interface according to an embodiment of the present invention; FIG. 2( b ) is a cross-sectional view of the metal cabin interface according to an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of the hanging holes of the pressure-bearing layer according to an embodiment of the present invention;

[0035] Figure 4 This is a schematic diagram of the airtight layer interface of an embodiment of the present invention;

[0036] Figure 5 This is a schematic diagram of the interface of the flame retardant layer according to an embodiment of the present invention;

[0037] FIG. 6( a ) is an overall schematic diagram of a soft pad according to an embodiment of the present invention; FIG. 6( b ) is a cross-sectional schematic diagram of a soft pad according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0039] The present invention proposes a highly reliable rigid-flexible sealing connection structure that can be disassembled and assembled multiple times, such as Figure 1 As shown, it includes a flexible membrane structure, a clamping screw 2, a gasket 3, a sealing ring 6, an anti-slip screw 9, and a soft cushion block 12.

[0040] The flexible membrane structure is composed of a pressure-bearing layer 13, an airtight layer and a flame-retardant layer from inside to outside the cabin. Each layer is bonded into a composite layer by adhesive. The main function of the flame-retardant layer is flame retardancy inside the cabin, the main function of the airtight layer is sealing, and the main function of the pressure-bearing layer 13 is to support the airtight layer and bear and transmit the internal pressure load.

[0041] The pressure-bearing layer 13, the airtight layer and the flame-retardant layer are connected to the metal cabin 1 independently. The metal cabin 1 is provided with a connection interface, which cooperates with the pressure-bearing layer interface, the airtight layer interface and the flame-retardant layer interface, such as Figure 2(a) , 2(b) As shown, the specific setting is as follows: a ring frame 7 is arranged along the circumference of the metal cabin 1, and each side of the ring frame 7 is chamfered; a sealing groove 15 and a number of evenly distributed compression screw holes 14 are arranged on the end face of the ring frame 7 close to the cabin, and the roughness of each surface of the sealing groove should be less than 1.6, wherein the specification of the screw hole 14 and the spacing between adjacent screw holes 14 are determined by the compression force requirements of the sealing ring. A number of evenly distributed hooks 8 are arranged along the circumference of the metal cabin below the ring frame 7 (the lower side points to the outside of the cabin), and 180 hooks are arranged in this embodiment, and the spacing between adjacent hooks 8 is determined by the hanging point load and the processing capacity of the production party. Each side of the hook 8 is chamfered, and the ring frame 7 and the hook 8 are integrated with the metal cabin 1. A screw hole 16 is processed on each hook 8 for installing an anti-slip screw 9. The ring frame 7 and the hook 8 are as close as possible. In order to ensure the processing space of the hook 8, the lower surface of the ring frame 7 (the lower side points to the outside of the cabin) is designed as an inclined surface. The screw hole 16 is used to install an anti-slip screw 9.

[0042] The pressure-bearing layer 13 is a membrane structure made of nylon-polyurethane coated fabric by cutting and heat-sealing, and a plurality of evenly distributed hanging holes 17 are arranged on the periphery, such as Figure 3As shown, the number, size and distribution of the hanging holes 17 are the same as those of the metal cabin hooks 8. The pressure-bearing layer 13 is hung on the hooks 8 of the metal cabin 1 through the hanging holes, and each hook 8 is provided with an anti-slip screw 9 to prevent the pressure-bearing layer 13 from falling off the hooks 8. The specific arrangement is as follows: a plurality of evenly distributed hooks 8 are arranged around the metal cabin 1, and the spacing between adjacent hooks 8 is determined according to the hanging point load and the processing capacity of the manufacturer. A plurality of evenly distributed hanging holes 17 are arranged on the periphery of the pressure-bearing layer 13. The hanging holes 17 and the hooks 8 are tightly matched, and the distribution is consistent with the hooks 8. On the one hand, it ensures that the pressure-bearing layer 13 is smoothly hung on the hooks 8, and on the other hand, it inhibits the pressure-bearing layer 13 from falling off the hooks 8. Under this connection method, the pressure-bearing layer 13 should have sufficient connection strength at the hanging holes 17 to prevent the hanging holes 17 from being damaged under the internal pressure load.

[0043] The airtight layer is formed by bonding the airtight film 10 and the second bonding ring 5 with adhesive. The airtight film is a membrane structure made of polyurethane film by cutting and heat-sealing. The adhesive should be a high-strength and tough adhesive. The second bonding ring 5 is a circular thin plate structure, and the material is a lightweight aluminum alloy, fiber-reinforced composite laminate, plastic, etc. The surface of the second bonding ring 5 pressing the sealing ring is the sealing surface, and the roughness should be less than 1.6. After the airtight film 10 and the second bonding ring 5 are bonded, a number of evenly distributed nail holes 18 are punched around the second bonding ring 5, such as Figure 4 As shown, the number of nail holes 18 and the screw holes 14 of the metal cabin 1 are equal and the distribution is the same. Then it is connected to the ring frame 7 of the metal cabin 1 through the clamping screws 2, and the sealing ring 6 is compressed. The clamping screws 2 are used to install the airtight layer and the flame retardant layer and provide the compression force required for the sealing ring to be compressed. Among them, the bonding surface of the airtight film 10 and the second adhesive ring 5 is the first sealing link, and the second adhesive ring 5 compresses the sealing ring 6 as the second sealing link to achieve sealing.

[0044] A plurality of sections of soft cushion blocks 12 are arranged between the pressure-bearing layer 13, the airtight membrane 10 and the bulkhead of the metal cabin 1 to fill the gaps between the ring frame 7, the metal bulkhead, the hook 8, the airtight layer and the pressure-bearing layer 13. Figure 6(a) , 6(b) As shown, the soft pad 12 is tightly fitted with the cabin body to support and protect the airtight membrane 10 from damage to the metal structure. The soft pad 12 is made of light foam or sponge, and the soft pad 12 is divided into multiple sections along the wall of the metal cabin 1. The soft pad 12 is machined with an embedded groove 20, which is tightly fitted between the ring frame 7 and the hook 8.

[0045] The flame retardant layer is formed by bonding the flame retardant cloth 11 and the first bonding ring 4. The flame retardant cloth 11 is formed by stitching and splicing Nomex flame retardant cloth or other flame retardant cloth, and the first bonding ring 4 is a circular thin plate structure, and the material is a lightweight aluminum alloy, fiber reinforced composite laminate, plastic, etc. After the outer periphery of the flame retardant cloth 11 is bonded to the first bonding ring 4, a number of evenly distributed nail holes 19 are processed along the first bonding ring 4, such as Figure 5 As shown, the number and distribution of the nail holes 19 and the screw holes 14 are equal. The nail holes 19 are connected to the ring frame 7 of the metal cabin 1 by screws 2.

[0046] An assembly process of a highly reliable rigid-flexible sealing connection structure that can be disassembled and assembled multiple times, the assembly process of the flexible membrane structure and the metal cabin 1 is the sealing ring 6, the pressure-bearing layer 13, the anti-drop screw 9, the soft pad 12, the airtight layer, and the flame-retardant layer. The disassembly process is the reverse process of the assembly process. The specific assembly process is as follows:

[0047] Step 1: Place the sealing ring 6 into the sealing groove 15;

[0048] Step 2: Set quadrant markings on the pressure-bearing layer 13 , the airtight film of the airtight layer, the flame-retardant cloth of the flame-retardant layer and the metal cabin to facilitate installation and positioning; transfer the flexible membrane structure from the opening of the metal cabin 1 to the inside of the metal cabin 1 .

[0049] Step 3: Align the quadrant marks on the pressure-bearing layer 13 with the quadrant marks on the metal cabin 1 , and hang the hanging holes of the pressure-bearing layer 13 on the hooks of the metal cabin 1 .

[0050] Step 4: Install the anti-slip screw 9. Install the anti-slip screw 9 to the screw hole 16. One end of the anti-slip screw 9 should be flush with the side of the hook 8, and the other end should not be allowed to hit the wall of the metal cabin 1. The thread is sealed with glue when the flexible membrane structure is installed for the last time.

[0051] Step 5: Install multiple sections of soft pads 12.

[0052] Step 6: Align the quadrant marks on the airtight layer with the quadrant marks on the metal cabin 1, place the adhesive ring 5 with the airtight film 10 on top of the ring frame 7 and the sealing ring 6, and install at least 4 screws 2 and 4 gaskets 3 to temporarily fix the airtight layer.

[0053] Step 7: Align the quadrant mark on the flame retardant layer with the quadrant mark on the metal cabin 1 , and place the first adhesive ring 4 with the flame retardant cloth on the second adhesive ring 5 .

[0054] Step 8: Remove screws 2 and gaskets 3 that temporarily fix the airtight layer, and install screws 2 and gaskets 3. Screw 2 should be installed diagonally, and pre-tightening force should be applied at multiple levels to make the product evenly stressed. Seal the screw heads with glue during the last installation.

[0055] The disassembly process of the rigid-flexible connection structure is the reverse process of the assembly process.

[0056] The above-described embodiments are only preferred specific implementations of the present invention. Common changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. A highly reliable rigid-flexible sealing connection structure that can be disassembled and assembled multiple times, used to connect metal cabins, characterized in that: Including flexible membrane structure, sealing ring, fasteners; The flexible membrane structure is a composite layer, which is composed of a pressure-bearing layer, an airtight layer and a flame-retardant layer from the inside to the outside of the metal cabin, and each layer is independently connected to the metal cabin; the pressure-bearing layer is used to support the airtight layer and bear and transmit the internal pressure load, the airtight layer is used for sealing, and the flame-retardant layer is used to flame-retard the metal cabin; The metal cabin is evenly provided with a number of hooks along the circumferential direction, the hooks serve as interfaces between the metal cabin and the pressure-bearing layer, and the pressure-bearing layer is hung on the hooks; the metal cabin is provided with a ring frame along the circumferential direction, and the ring frame is located above the hooks; a sealing groove and a number of evenly distributed screw holes are provided on the end face of the ring frame, the airtight layer and the ring frame are pressed tightly by a sealing ring placed in the sealing groove, and the screw holes are connected to the airtight layer and the flame-retardant layer by fasteners, so as to realize the connection between the metal cabin and the airtight layer, and the metal cabin and the flame-retardant layer.

2. A highly reliable rigid-flexible sealed connection structure that can be disassembled and assembled multiple times according to claim 1, characterized in that: The pressure-bearing layer is a membrane structure made of nylon-polyurethane coated fabric by cutting and heat-sealing, and a plurality of hanging holes are evenly arranged on the periphery. The shape, size and distribution of the hanging holes are the same as those of the hooks. The hanging holes correspond to the hooks one by one and are tightly fitted so that the pressure-bearing layer can be hung on each hook.

3. A highly reliable rigid-flexible sealed connection structure capable of multiple assembly and disassembly according to claim 2, characterized in that: A screw hole is provided on each hook for installing an anti-slip screw to prevent the pressure-bearing layer from slipping out of the hook. One end of the anti-slip screw is flush with the side of the hook, and the other end is not allowed to touch the metal cabin bulkhead.

4. The highly reliable rigid-flexible sealed connection structure capable of multiple assembly and disassembly according to claim 1, characterized in that: The airtight layer is formed by bonding an airtight film and a second bonding ring. The airtight film is a membrane structure made of a polyurethane film by cutting and heat-sealing. The second bonding ring is a circular plate structure. The second bonding ring and the ring frame are compressed and sealed by a sealing ring. The second bonding ring is evenly provided with a plurality of nail holes in the circumferential direction. The number and distribution of the nail holes are the same as the number and distribution of the screw holes on the ring frame. Fasteners are passed through the nail holes and the corresponding screw holes to achieve a fixed connection between the airtight layer and the metal cabin.

5. The highly reliable rigid-flexible sealing connection structure capable of multiple assembly and disassembly according to claim 4, characterized in that: The material of the second adhesive ring is preferably a light aluminum alloy, a fiber-reinforced composite laminate or plastic, and one side of the second adhesive ring pressing the sealing ring is a sealing surface with a roughness less than 1.

6.

6. The highly reliable rigid-flexible sealed connection structure capable of multiple assembly and disassembly according to claim 4, characterized in that: The surface of the ring frame facing the outside of the cabin is designed to be a slope, and the roughness of each surface of the sealing groove is less than 1.

6.

7. The highly reliable rigid-flexible sealed connection structure capable of multiple assembly and disassembly according to claim 1, characterized in that: The flame retardant layer includes a flame retardant cloth and a first bonding ring. The first bonding ring is a circular plate structure, and the outer periphery of the flame retardant cloth is bonded to the first bonding ring. The first bonding ring is evenly provided with a plurality of nail holes along the annular direction. The number and distribution of the nail holes are the same as the number and distribution of the screw holes. Fasteners are passed through the nail holes and the corresponding screw holes to achieve a fixed connection between the airtight layer and the metal cabin. The material of the first bonding ring is preferably a lightweight aluminum alloy, a fiber-reinforced composite laminate or plastic.

8. The highly reliable rigid-flexible sealed connection structure capable of multiple assembly and disassembly according to claim 1, characterized in that: A plurality of soft pads are arranged between the pressure-bearing layer, the airtight layer and the bulkhead of the metal cabin to fill the gaps between the ring frame, the metal bulkhead, the hook, the airtight layer and the pressure-bearing layer to support and protect the airtight layer.

9. The highly reliable rigid-flexible sealed connection structure capable of multiple assembly and disassembly according to claim 1, characterized in that: The soft pad is made of light foam or sponge and is divided into multiple sections along the metal cabin bulkhead. An embedded groove is processed on the soft pad and is embedded between the ring frame and the hook through a tight fit.

10. A method for assembling the high-reliability rigid-flexible sealing connection structure according to claim 1, characterized in that: include: Step 1: Install the sealing ring into the sealing groove; Step 2: Set quadrant marks on the pressure-bearing layer, airtight layer, flame-retardant layer, and metal cabin, align the quadrant marks on the pressure-bearing layer with the quadrant marks on the metal cabin, and hang the hanging holes of the pressure-bearing layer on the hooks of the metal cabin; Step 3: Install the anti-slip screw. One end of the anti-slip screw should be flush with the side of the hook, and the other end should not touch the metal cabin wall. Step 4: Install multiple soft pads; Step 5: Align the quadrant mark on the airtight layer with the quadrant mark on the metal cabin, place the second bonding ring with the airtight film on top of the ring frame and the sealing ring, and install at least 4 fasteners to temporarily fix the airtight layer; Step 6: Align the quadrant mark on the flame retardant layer with the quadrant mark on the metal cabin, and place the first bonding ring with the flame retardant cloth on top of the second bonding ring; Step 7: Remove the fasteners that temporarily fix the airtight layer, and reinstall the fasteners to connect the screw holes with the airtight layer and flame retardant layer. The fasteners are installed diagonally, and pre-tightening force is applied at multiple levels to make the product evenly stressed. Seal the screw heads with glue during the last installation.

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