Composite heat shield assembly

Abstract

The invention relates to the technical field of aviation brake airplane wheel thermal protection, in particular to a composite heat screen assembly which comprises a heat insulation layer, a hot face protection layer and a cold face protection layer, the hot face protection layer is welded to the inner side of the cold face protection layer, and a gap is formed between the hot face protection layer and the cold face protection layer and used for being filled with a composite heat insulation material to form the heat insulation layer. The composite heat shield is installed on the inner side of an aircraft wheel hub, the sections of the hot face protection layer and the cold face protection layer are arc-shaped, the radian of the sections is consistent with that of the aircraft wheel hub, the heat insulation layer is made of a long crystal fiber composite heat insulation material, the hot face protection layer and the cold face protection layer are made of 022Cr17Ni12Mo2, the heat insulation effect is good, and the service life of the heat insulation layer is prolonged. Meanwhile, due to material change and thickness increase, the rigidity of the assembly is enhanced, the deformation condition in the using process is reduced, the position of the heat insulation layer on the cold face protection layer can be adjusted according to different aviation aircraft wheel space structures, and universality is high.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aviation brake wheel heat protection, and particularly relates to a composite heat shield assembly. BACKGROUND

[0002] The aviation brake wheel is installed on the landing gear of an airplane and is composed of a wheel and a brake device. The wheel assembly is externally sleeved with a tire. When the tire rolls, the brake device converts the kinetic energy of the airplane into heat energy, which is dissipated through heat radiation or heat transfer. The wheel and the tire are outside the brake device, and part of the heat is absorbed by the wheel and the tire. The temperature of the gas inside the wheel and the tire is increased, and the pressure inside the tire is increased. In order to prevent the tire from exploding due to too high pressure, a heat-sensitive device is usually designed on the wheel assembly. When the temperature of the wheel is too high, the pressure of the tire is released.

[0003] With the continuous improvement of the design requirements of modern airplanes, the kinetic energy converted by the brake wheel is larger and larger, and the temperature of the brake device is higher and higher, which leads to a higher and higher temperature of the wheel. At present, the heat protection mode adopted by the aviation wheel is a heat shield made of a single layer of stainless steel sheet. The heat insulation effect cannot meet the requirements, and the single layer of stainless steel sheet has low rigidity and is prone to deformation in a high-temperature environment. The maintenance cycle is short. SUMMARY

[0004] To solve the problems mentioned in the background, the present application provides a composite heat shield assembly.

[0005] The present application discloses the following technical scheme: a composite heat shield assembly, comprising a heat insulation layer, a hot surface protection layer and a cold surface protection layer, the hot surface protection layer is welded on the inner side of the cold surface protection layer, a gap is formed between the hot surface protection layer and the cold surface protection layer for filling a composite heat insulation material to form the heat insulation layer, and the composite heat shield is installed on the inner side of the hub of the aviation wheel.

[0006] Further, the section of the hot surface protection layer and the cold surface protection layer is arc-shaped, and the curvature is consistent with the hub of the wheel.

[0007] Further, the material of the heat insulation layer is a long-crystal fiber composite heat insulation material.

[0008] Further, the material of the hot surface protection layer and the cold surface protection layer is 022Cr17Ni12Mo2.

[0009] Advantages: Compared with the prior art, the composite heat shield assembly of the present application has an improved heat insulation effect of 30% compared with the single-layer heat shield. Meanwhile, due to the change of the material and the increase in the thickness, the rigidity of the heat shield assembly is strengthened, the deformation in use is reduced, and the position of the heat insulation layer in the cold surface protection layer can be adjusted according to different space structures of the aviation wheel, so that the universality is high. BRIEF DESCRIPTION OF DRAWINGS

[0010] Fig. 1 is a schematic diagram of the overall structure of the present application; Fig. 2 is a schematic diagram of the installation of the present application; In the figure: 1 - thermal insulation layer, 2 - hot face protection layer, 3 - cold face protection layer, 4 - wheel hub. DETAILED DESCRIPTION

[0011] As shown in Figs. 1-2 , a composite heat shield assembly includes a thermal insulation layer 1, a hot face protection layer 2 and a cold face protection layer 3, the hot face protection layer 2 is welded inside the cold face protection layer 3, a gap is formed between the hot face protection layer 2 and the cold face protection layer 3 for filling a composite thermal insulation material to form the thermal insulation layer 1, the composite heat shield is installed inside the aircraft wheel hub 4, the cross section of the hot face protection layer 2 and the cold face protection layer 3 is arc-shaped, the curvature is consistent with the aircraft wheel hub 4, which facilitates the installation of the heat shield on the aircraft wheel, the material of the thermal insulation layer 1 is long crystal fiber composite thermal insulation material, such as glass long fiber composite thermal insulation material: taking glass fiber as the main raw material, through high temperature melting, short cutting, filamentation and needling process, a interlaced network structure is formed. Its normal temperature thermal conductivity is 0.030-0.040 W / m・K, the temperature resistance can reach 650-700℃, it has the characteristics of A1 grade non-combustible, water-repellent, moisture-proof, acid and alkali corrosion-resistant, etc., effectively isolating the heat generated by the brake disc during the braking process of the aircraft wheel; the material grade of the hot face protection layer 2 and the cold face protection layer 3 is 022Cr17Ni12Mo2, the material is 022Cr17Ni12Mo2 stainless steel, also known as titanium steel, which belongs to low-carbon austenitic stainless steel, has excellent corrosion resistance and pitting resistance, high temperature strength is excellent, high temperature environment is not easy to deform, can ensure the structural stability of the heat shield assembly and protect the thermal insulation layer.

[0012] During processing, the hot face protection layer 2 and the cold face protection layer 3 are bent, the bending curvature is consistent with the aircraft wheel hub 4, then the hot face protection layer 2 is welded inside the cold face protection layer 3, after filling the composite thermal insulation material in the reserved gap, the gap is closed to prevent the composite thermal insulation material from leaking out; as shown in Fig. 2 , a recess is provided on the boss inside the aircraft wheel hub 4, the composite heat shield assembly is inserted into the recess of the boss of the aircraft wheel hub 4, so that the heat shield assembly is stably clamped, the hot face protection layer 2 faces the inside of the aircraft wheel hub 4, the inner and outer protection layers protect the thermal insulation layer 1, isolate the aircraft wheel and the brake device, and effectively avoid the temperature rise of the aircraft wheel.

[0013] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can make equivalent replacement or change according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A composite heat shield assembly, characterized by: The application relates to a composite heat shield for an aircraft wheel hub (4), comprising a heat insulation layer (1), a hot face protection layer (2) and a cold face protection layer (3), wherein the hot face protection layer (2) is welded to the inner side of the cold face protection layer (3), a gap is formed between the hot face protection layer (2) and the cold face protection layer (3) for filling a composite heat insulation material to form the heat insulation layer (1), and the composite heat shield is arranged in the inner side of the aircraft wheel hub (4).

2. The compound heat shield assembly of claim 1, wherein: The section of the hot face protection layer (2) and the cold face protection layer (3) is arc-shaped, and the arc is consistent with the aircraft wheel hub (4).

3. The compound heat shield assembly of claim 1, wherein: The material of the heat insulation layer (1) is long-crystal fiber composite heat insulation material.

4. The compound heat shield assembly of claim 1, wherein: The material of the hot face protection layer (2) and the cold face protection layer (3) is 022Cr17Ni12Mo2.

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