Lightweight flexible firewall composite structure

Abstract

The utility model belongs to the technical field of airplane general structure design, and particularly relates to a light flexible firewall combined structure. Comprising metal plates and fireproof felts, the fireproof felts are fixed on the upper and lower surfaces of the metal plate; the metal plate is provided with a plurality of lightening holes. The high-temperature-resistant flexible fireproof felt is combined with light metal plates such as aluminum alloy to form a light flexible fireproof wall combined structure, an engine compartment is isolated, and the use and maintenance requirements of an airplane can be met. The fireproof felt has the functions of fire prevention, heat insulation, low air permeability and oil-gas isolation, and metal materials such as aluminum alloy with small density and relatively low use temperature can be selected as the main structure of the firewall. Lightening holes can be formed in the metal plate as much as possible according to the weight reduction principle, and meanwhile the fireproof felt is light in weight, good in flexibility, capable of being bent, folded, compressed and laid at will according to the shape. According to the firewall combined structure provided by the utility model, the weight of the structure can be reduced while the flight safety of an airplane is guaranteed.

Description

Technical Field

[0001] This utility model belongs to the field of aircraft general structural design technology, specifically relating to a lightweight flexible firewall combination structure. Background Technology

[0002] The firewall in a twin-engine aircraft isolates the left and right engine nacelles, ensuring that if a fire breaks out in one engine nacelle, the other engine nacelle remains unaffected for a period of time. The firewall plays a crucial role in aircraft safety. The "Aircraft Engine (Novice) Nacelle Thermal Insulation Design Guidelines" stipulate that: "All potentially fire-prone areas must be separated by firewalls. The firewalls should be made of stainless steel plates no less than 0.40 mm thick or other materials capable of withstanding a flame of 1100°C for 15 minutes, and should be resistant to liquids and vapors."

[0003] Because aircraft firewalls are directly exposed to the impact of flames, traditional aircraft firewalls typically use high-temperature resistant metal materials such as stainless steel and titanium alloys, with fire-retardant materials sprayed or brushed onto the surface to meet fireproof and heat-insulating requirements. For example, using a low-density fire-retardant and heat-insulating silicone sealant to coat a large area of ​​stainless steel to ensure that flames at 1100℃ cannot penetrate requires a certain thickness on each side to meet fireproofing requirements. This type of firewall is a large, solid metal plate and cannot be designed with openings. Steel and titanium are also high-density metal materials, so this structural form incurs a significant structural weight penalty, resulting in a heavy load. Utility Model Content

[0004] The purpose of this invention is to combine flexible fireproof felt with lightweight metal partitions, with light-reducing holes on the metal partitions, which can significantly reduce weight while achieving heat insulation compared to traditional firewall structures.

[0005] The technical solution of this utility model is as follows: a lightweight and flexible fireproof wall combination structure, including a metal plate and a fireproof felt; the fireproof felt is fixed on the upper and lower surfaces of the metal plate; the metal plate has a plurality of weight-reducing holes.

[0006] Furthermore, the two layers of fireproof felt are sewn and fixed to the metal plate by fireproof fiber threads, which are arranged along the edge of the metal plate.

[0007] Furthermore, several fireproof fiber threads are made through holes at the edge of the weight reduction holes in the metal plate, and two layers of fireproof felt are sewn together along the edge of the weight reduction holes for reinforcement and fixation.

[0008] Furthermore, the fireproof felt is made of high-temperature resistant fireproof fiber as the base material, covered with fireproof fiber cloth on both sides, and sewn with fireproof fiber thread.

[0009] Furthermore, a high-temperature resistant adhesive is applied between the fireproof felt and the metal plate to ensure overall fixation.

[0010] Furthermore, the metal plate has several slots along its edge, serving as clearance space for coordination with surrounding accessory structures during use.

[0011] Furthermore, the metal plate is made of aluminum alloy.

[0012] The beneficial effects of this invention are as follows: A lightweight and flexible firewall structure is formed by combining high-temperature resistant flexible fireproof felt with lightweight metal plates such as aluminum alloy to isolate the engine compartment, meeting the requirements for aircraft use and maintenance. The fireproof felt possesses fireproof and heat insulation properties, low air permeability, and oil and gas isolation. Low-density metal materials such as aluminum alloy with relatively low operating temperatures can be selected as the main structure of the firewall. Lightweight holes can be created on the metal plates according to weight reduction principles. Simultaneously, the fireproof felt is lightweight and flexible, allowing it to be bent, folded, compressed, and laid out in any shape. This firewall structure reduces structural weight while ensuring aircraft flight safety. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0014] Figure 2 This is a schematic diagram of the usage state of this utility model;

[0015] Figure 3 This is a cross-sectional schematic diagram of the present invention;

[0016] Figure 4 This is a schematic diagram of the fireproof felt structure of this utility model;

[0017] Figure 5 This is a schematic diagram of the sewing process for the fireproof felt of this utility model;

[0018] Figure 6 This is a schematic diagram of the metal plate structure of this utility model. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] See appendix Figure 1 , 2As shown in Figure 3, in one embodiment of this utility model, the lightweight flexible firewall combination structure is composed of a new type of flexible fireproof felt wrapped around two metal plates such as aluminum alloy in the middle. Lightening holes are opened on the metal plates such as aluminum alloy for structural weight reduction and stitching of the fireproof felt.

[0021] The fireproof felt used in this utility model is made of high-temperature resistant fireproof fiber as the base material, covered with fireproof fiber cloth on both sides, and sewn with fireproof fiber thread. Figure 4 , 5 As shown; to facilitate sewing, several small through holes are made on the edge of the aluminum alloy metal plate and around the light-reducing holes, allowing the fireproof fiber thread to pass through easily. The fireproof felt is combined with the metal plate by sewing, including sewing around the holes and sewing around the perimeter. Subsequent bonding can be achieved by applying high-temperature adhesive or using snap fasteners.

[0022] In this design, several differently shaped weight-reducing holes are designed on the aluminum alloy or other metal plate for weight reduction and stitching with the fireproof felt. The holes should meet the requirements of structural strength and rigidity, such as... Figure 6 ;

[0023] Firewall metal partition structure design: Based on the aircraft's strength and stiffness requirements, the firewall metal partition is designed, and the structural form, structural parameters, openings, etc. that meet the design requirements are selected; the upper and lower surfaces of the metal plate are arranged with ribs of a certain height, and the flexible fireproof felt can be arranged according to the shape.

[0024] To further improve fire resistance, the performance of fireproof felt was tested: several typical specifications of fireproof felt were selected and tested for fire resistance, vibration, environment, air tightness, etc. The thickness of the fireproof felt was selected based on the principle of light weight while meeting the design requirements for fire resistance and environment.

[0025] In some design cases, improved designs have been proposed for the combination of fireproof felt and metal plates: two methods are adopted: edge stitching and perimeter stitching, and the stitching dimensions are specified, including parameters such as the edge distance of the stitches and the spacing between the stitches; at the same time, fireproof and heat-insulating coatings can be sprayed or coated to further enhance the fireproof performance of the firewall.

[0026] This new lightweight flexible firewall combination structure can use lightweight metal plates such as aluminum alloy with low operating temperature as the internal structure, and can be perforated on the metal plates. While achieving the firewall function, it surpasses the traditional solid metal plate (non-perforated) firewalls such as titanium alloy and steel structures, with a significant weight advantage, greatly reducing the structural weight and improving aircraft performance. At the same time, it is suitable for the structural design of other parts of the aircraft that require heat insulation and fire protection, and has the value of widespread application.

[0027] The above description is merely a specific embodiment of this utility model, providing a detailed description of the utility model. Parts not covered in detail are conventional techniques. However, the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this utility model should be included within the protection scope of this utility model. The protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A lightweight, flexible firewall composite structure, characterized in that, It includes a metal plate and a fireproof felt; the fireproof felt is fixed to the upper and lower surfaces of the metal plate; the metal plate has several weight-reducing holes.

2. The lightweight flexible firewall combination structure as described in claim 1, characterized in that, The two layers of fireproof felt are sewn and fixed to the metal plate by fireproof fiber thread, which is arranged along the edge of the metal plate.

3. The lightweight flexible firewall combination structure as described in claim 2, characterized in that, Several fireproof fiber threads are made through holes at the edge of the weight reduction holes in the metal plate, and two layers of fireproof felt are sewn together along the edge of the weight reduction holes for reinforcement and fixation.

4. The lightweight flexible firewall combination structure as described in claim 1, characterized in that, The fireproof felt is made of high-temperature resistant fireproof fiber as the base material, covered with fireproof fiber cloth on both sides, and sewn with fireproof fiber thread.

5. The lightweight flexible firewall combination structure as described in claim 1, characterized in that, A high-temperature resistant adhesive is also applied between the fireproof felt and the metal plate.

6. The lightweight flexible firewall combination structure as described in claim 1, characterized in that, The metal plate has several slots along its edge, which serve as clearance space for it to cooperate with surrounding accessory structures during use.

7. The lightweight flexible firewall combination structure as described in claim 1, characterized in that, The metal plate is made of aluminum alloy.

Images