A double graphite sealing device with self-insulation structure

Abstract

The application belongs to the technical field of aero-engines, and particularly relates to a double graphite sealing device with a self-heat-insulation structure. The device comprises a heat-insulation assembly, a sealing seat assembly, a clamping ring, a press ring assembly, a circumferential spring and a sealing graphite piece. The sealing seat assembly comprises a sealing seat and a sealing jacket, and the two form a first gas ring cavity; the heat-insulation assembly and the sealing jacket form a second gas ring cavity, and the two are communicated through a gas guiding channel. After being split, the sealing gas enters the first gas ring cavity and the inner side of the sealing seat to perform a sealing function, and the other part enters the second gas ring cavity to take away heat and then is discharged, thereby forming an active heat-insulation gas flow barrier. The heat-insulation assembly adopts a double-wall structure, is filled with high-silica glass fiber cloth in the inside, and effectively blocks external heat conduction and heat radiation in combination with the split heat-insulation gas flow.

Description

Technical Field

[0001] This application belongs to the field of aero-engine technology, and specifically relates to a double graphite sealing device with a self-insulating structure. Background Technology

[0002] The function of the double graphite seal device is to use gas to seal the engine bearing cavity, ensuring the lubricating oil seal. The sealing bleed gas flowing through the double graphite seal device enters the engine bearing cavity. The temperature of the sealing bleed gas affects the temperature inside the engine bearing cavity, and consequently, the lifespan of the components within the engine bearing cavity.

[0003] Normally, inter-shaft bearings are located in the rear bearing cavity of an engine. However, to meet the demands of higher engine speeds, the DN value of these bearings is now very high, resulting in significant heat generation and high temperatures within the rear bearing cavity. The engine rear bearing cavity is typically located after the high- and low-pressure turbines, and the high-temperature external environment heats it through heat conduction and radiation. Therefore, the components in the engine rear bearing cavity require heat insulation structures, and the double graphite seal device installed in the rear bearing cavity urgently needs to achieve self-insulating functionality. Currently, the double graphite seal device cannot meet this self-insulating requirement. Summary of the Invention

[0004] To address the aforementioned issues, this application provides a double-layer graphite sealing device with a self-insulating structure, comprising: an insulation component (1), a sealing seat component (2), a retaining ring (3), a pressure ring component (4), a circumferential spring (5), and a sealing graphite component (6).

[0005] The sealing seat assembly (2), sealing outer sleeve (13), and sealing seat (14) are described. The sealing seat (14) includes a cylindrical section and a disc located at one end of the cylindrical section. An air vent is provided on the disc. The sealing outer sleeve (13) is fitted over the cylindrical section. A first gas annular cavity is formed between the inner wall of the sealing outer sleeve (13) and the outer wall of the cylindrical section.

[0006] The heat insulation component (1) includes a heat insulation cylinder section and a heat insulation plate. A second gas annular cavity is formed between the heat insulation cylinder section and the outer wall of the sealing jacket (13). An air intake channel is formed between the heat insulation plate and the disc. The air intake channel inlet draws air through the air intake hole, and the outlet is connected to the first gas annular cavity. The sealing graphite part (6) is installed inside the cylinder section of the sealing seat (14) through the pressure ring assembly (4) and the retaining ring (3). The sealing seat (14) has an exhaust hole connected to the first gas annular cavity at the location of the sealing graphite part (6). The sealing seat assembly (2) has a through hole connecting the second gas annular cavity and the first gas annular cavity. The second gas annular cavity exhausts air through the end of the cylinder section of the sealing seat assembly (2).

[0007] Preferably, the heat insulation component (1) has a double-wall structure, including a heat insulation skin (9), a heat insulation seat (11), and heat insulation material filled in the closed cavity formed by the two; the heat insulation skin (9) and the heat insulation seat (11) are fixed by welding at both ends.

[0008] Preferably, the heat insulation material is high silica glass fiber cloth (10).

[0009] Preferably, the sealing seat assembly (2) further includes a positioning pin (12) and a first anti-rotation pin (15); the positioning pin (12) is used to realize the installation positioning of the pressure ring assembly (4) and the sealing seat assembly (2); the first anti-rotation pin (15) is used to prevent the sealing graphite part (6) from rotating circumferentially relative to the sealing seat assembly (2).

[0010] Preferably, the pressure ring assembly (4) includes a pressure ring (16) and a second anti-rotation pin (17); the second anti-rotation pin (17) is used to prevent the sealing graphite element (6) from rotating circumferentially relative to the pressure ring assembly (4).

[0011] Preferably, the retaining ring (3) is used to limit the axial displacement of the circumferential spring (5), the sealing graphite part (6) and the pressure ring assembly (4).

[0012] Preferably, the heat insulation component (1) is detachably connected to the sealing seat component (2) by bolts (7) and nuts (8).

[0013] Preferably, the sealing jacket (13) is provided with a vent hole for introducing gas from the second gas ring cavity and allowing it to flow out through the end face groove between the heat insulation component (1) and the sealing seat component (2).

[0014] Preferably, the device is applied to the rear bearing cavity sealing structure of an aero-engine or gas turbine.

[0015] The double-layer graphite sealing device with a self-insulating structure described in this invention can achieve self-insulating function. Its internal structure includes an insulating cavity and a double-layered insulating wall, which together minimize the heating impact of the high-temperature environment outside the engine rear bearing cavity on the sealing bleed air. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a double graphite sealing device with a self-insulating structure;

[0017] Figure 2 This is a schematic diagram of the thermal insulation component;

[0018] Figure 3 This is a schematic diagram of the sealing seat assembly;

[0019] Figure 4 This is a schematic diagram of the pressure ring assembly. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are only some embodiments of this application, not all embodiments. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings. A double-layer graphite sealing device with a self-insulating structure is shown in the schematic diagram below. Figures 1-4 It includes a heat insulation component (1), a sealing seat component (2), a retaining ring (3), a pressure ring component (4), a circumferential spring (5), a sealing graphite component (6), a bolt (7), and a nut (8).

[0021] It includes a heat insulation component (1), a sealing seat component (2), a retaining ring (3), a pressure ring component (4), a circumferential spring (5), and a sealing graphite component (6);

[0022] The sealing seat assembly (2), sealing outer sleeve (13), and sealing seat (14) are described. The sealing seat (14) includes a cylindrical section and a disc located at one end of the cylindrical section. An air vent is provided on the disc. The sealing outer sleeve (13) is fitted over the cylindrical section. A first gas annular cavity is formed between the inner wall of the sealing outer sleeve (13) and the outer wall of the cylindrical section.

[0023] The heat insulation component (1) includes a heat insulation cylinder section and a heat insulation plate. A second gas annular cavity is formed between the heat insulation cylinder section and the outer wall of the sealing jacket (13). An air intake channel is formed between the heat insulation plate and the disc. The air intake channel inlet draws air through the air intake hole, and the outlet is connected to the first gas annular cavity. The sealing graphite part (6) is installed inside the cylinder section of the sealing seat (14) through the pressure ring assembly (4) and the retaining ring (3). The sealing seat (14) has an exhaust hole connected to the first gas annular cavity at the location of the sealing graphite part (6). The sealing seat assembly (2) has a through hole connecting the second gas annular cavity and the first gas annular cavity. The second gas annular cavity exhausts air through the end of the cylinder section of the sealing seat assembly (2).

[0024] The heat insulation component (1) is a double-walled structure with heat insulation. The cavity sealed by the double walls is filled with heat insulation material that can isolate and protect against overheated air from the outside. It includes a heat insulation skin (9), a high-silica fiberglass cloth (10), and a heat insulation seat (11). The heat insulation skin (9) and the heat insulation seat (11) are welded together at both ends. Before welding, the cavity formed by the heat insulation skin (9) and the heat insulation seat (11) is filled with high-silica fiberglass cloth (10). The heat insulation component (1) itself has a heat insulation function.

[0025] The sealing seat assembly (2) includes a locating pin (12), a sealing sleeve (13), a sealing seat (14), and an anti-rotation pin (15). The locating pin (12) and the anti-rotation pin (15) are assembled with the sealing seat (14) by an interference fit. The sealing sleeve (13) and the sealing seat (14) are connected together by welding.

[0026] The pressure ring assembly (4) includes a pressure ring (16) and an anti-rotation pin (17). The anti-rotation pin (17) is assembled with the pressure ring (16) by an interference fit.

[0027] The assembly process of the double graphite sealing device with self-insulating structure is as follows: the circumferential spring (5), the sealing graphite component (6), the pressure ring assembly (4), and the retaining ring (3) are sequentially assembled into the sealing seat assembly (2). The sealing graphite component (6) and the sealing seat assembly (2) are prevented from circumferential rotation by an anti-rotation pin (15). The pressure ring assembly (4) and the sealing seat assembly (2) are installed and positioned by a positioning pin (12). The sealing graphite component (6) and the pressure ring assembly (4) are prevented from circumferential rotation by an anti-rotation pin (17). The purpose of installing the retaining ring (3) is to prevent axial movement of the circumferential spring (5) and the sealing graphite component (6) after they are assembled into the sealing seat assembly (2). The heat insulation component (1) is assembled together with the sealing seat assembly (2) by bolts (7) and nuts (8).

[0028] The double-layer graphite sealing device with a self-insulating structure has the following sealing and venting path: Figure 1 The arrows indicate the flow path. After being introduced into the air duct formed by the heat insulation component (1) and the sealing seat component (2), the sealing air is divided into two paths. One path is introduced into the cavity formed by the pressure ring component (4), the circumferential spring (5), the sealing graphite component (6), and the sealing seat component (2), which serves as a sealing function. The other path is introduced into the heat insulation cavity formed by the heat insulation component (1) and the sealing seat component (2) through the small hole on the sealing outer sleeve (13), and flows out through the end face groove between the heat insulation component (1) and the sealing seat component (2), which serves as a heat insulation function.

[0029] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A double-layer graphite sealing device with a self-insulating structure, characterized in that, include: It includes a heat insulation component (1), a sealing seat component (2), a retaining ring (3), a pressure ring component (4), a circumferential spring (5), and a sealing graphite component (6); The sealing seat assembly (2), sealing outer sleeve (13), and sealing seat (14) are described. The sealing seat (14) includes a cylindrical section and a disc located at one end of the cylindrical section. An air vent is provided on the disc. The sealing outer sleeve (13) is fitted over the cylindrical section. A first gas annular cavity is formed between the inner wall of the sealing outer sleeve (13) and the outer wall of the cylindrical section. The heat insulation component (1) includes a heat insulation cylinder section and a heat insulation plate. A second gas ring cavity is formed between the heat insulation cylinder section and the outer wall of the sealing jacket (13). An air intake channel is formed between the heat insulation plate and the disc. The air intake channel inlet draws air through the air intake hole, and the outlet is connected to the first gas ring cavity. The sealing graphite part (6) is installed inside the cylinder section of the sealing seat (14) through the pressure ring assembly (4) and the retaining ring (3). The sealing seat (14) has an exhaust hole connected to the first gas ring cavity at the location of the sealing graphite part (6). The sealing seat assembly (2) has a through hole connecting the second gas ring cavity and the first gas ring cavity. The second gas ring cavity exhausts air through the end of the cylinder section of the sealing seat assembly (2).

2. The double-layer graphite sealing device with a self-insulating structure as described in claim 1, characterized in that, The heat insulation component (1) has a double-wall structure, including a heat insulation skin (9), a heat insulation seat (11), and heat insulation material filled in the closed cavity formed by the two; the heat insulation skin (9) and the heat insulation seat (11) are fixed by welding at both ends.

3. The double-layer graphite sealing device according to claim 2, characterized in that, The thermal insulation material is high silica glass fiber cloth (10).

4. The double-layer graphite sealing device according to claim 1, characterized in that, The sealing seat assembly (2) further includes a positioning pin (12) and a first anti-rotation pin (15); the positioning pin (12) is used to realize the installation positioning of the pressure ring assembly (4) and the sealing seat assembly (2); the first anti-rotation pin (15) is used to prevent the sealing graphite part (6) from rotating circumferentially relative to the sealing seat assembly (2).

5. The double-layer graphite sealing device according to claim 1, characterized in that, The pressure ring assembly (4) includes a pressure ring (16) and a second anti-rotation pin (17); the second anti-rotation pin (17) is used to prevent the sealing graphite element (6) from rotating circumferentially relative to the pressure ring assembly (4).

6. The double-layer graphite sealing device according to claim 1, characterized in that, The retaining ring (3) is used to limit the axial displacement of the circumferential spring (5), the sealing graphite part (6) and the pressure ring assembly (4).

7. The double-layer graphite sealing device according to claim 1, characterized in that, The heat insulation component (1) is detachably connected to the sealing seat component (2) by bolts (7) and nuts (8).

8. The double-layer graphite sealing device according to claim 1, characterized in that, The sealing jacket (13) is provided with a vent hole for introducing gas from the second gas ring cavity and allowing it to flow out through the end face groove between the heat insulation component (1) and the sealing seat component (2).

9. The double-layer graphite sealing device according to claim 1, characterized in that, The device is used in the sealing structure of the rear bearing cavity of aero engines or gas turbines.

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