A fingertip-brush combined multi-stage low hysteresis seal structure

Abstract

The application relates to a multi-stage low-hysteresis sealing structure combined with a fingertip and a brush, and belongs to the technical field of aero-engine sealing. The application comprises a mounting seat, a fusion welding area I, a front baffle, high-pressure fingertip pieces, low-pressure fingertip pieces, a rear baffle I, a partition plate, a rear baffle II, a rear baffle III, a brush ring, screws, a fusion welding area II, brush filaments and a rotor. The front baffle, the high-pressure fingertip pieces, the low-pressure fingertip pieces and the rear baffle I form a fingertip sealing structure, a stepped groove is arranged on the left side of the rear baffle I, the stepped groove of the rear baffle I and the right side of the low-pressure fingertip pieces form a stepped cavity I, and the brush ring is fixedly connected in the stepped cavity I of the rear baffle I through the screws. The sealing structure has good self-adaptability, can reduce the sealing leakage rate through the combination of fingertip sealing and brush sealing, can reduce the 'hysteresis' effect of the multi-stage sealing device, can reduce the leakage rate, has better sealing performance, can increase the working life of the brush sealing and the fingertip sealing, and has the advantages of the prior art.

Description

Technical Field

[0001] This invention relates to a fingertip-brush composite multi-stage low-hysteresis sealing structure, belonging to the field of aero-engine sealing technology. Background Technology

[0002] Sealing devices are key components of rotating machinery such as aero-engines, gas turbines, and compressors, playing a crucial role in preventing leakage of working media and saving energy. With the rapid development of the aerospace industry, the pressure difference between upstream and downstream components is increasing, thus limiting the pressure-bearing capacity of single-stage sealing devices. Currently, multi-stage brush seals are the most common solution under high pressure differential conditions. However, in actual operation, under high pressure differential conditions, brush seals have relatively low stiffness, while the pressure drop between downstream stages is consistently significant, leading to premature seal failure. Furthermore, the hysteresis characteristics of multi-stage brush seals are also pronounced under high pressure differential conditions. Meanwhile, while brush seals are flexible seals, their application is limited due to the easy wear of the brush bristles and their high cost. Finger seals, on the other hand, have better adaptability. During operation, finger seals provide a sealing effect similar to brush seals, but their manufacturing cost is only 40% to 50% of that of brush seals, and they do not experience brush bristle breakage or tip breakage during operation. Therefore, combining the characteristics of finger seals and brush seals can improve the pressure-bearing capacity and reduce leakage while lowering the cost of the sealing device. Summary of the Invention

[0003] The purpose of this invention is to provide a multi-stage low-hysteresis sealing structure with a fingertip-brush composite design to solve the problems of large interstage pressure drop and hysteresis caused by rotor vibration in existing sealing devices under large pressure differential conditions.

[0004] This invention is achieved according to the following technical solution: a multi-stage low-hysteresis sealing structure of fingertip-brush composite, characterized in that it includes a mounting base 1, a welding zone I2, a front baffle 3, a high-pressure fingertip plate 4, a low-pressure fingertip plate 5, a rear baffle I6, a partition 7, a rear baffle II 8, a rear baffle III 9, a brush ring 10, a screw 11, a welding zone II 12, a brush filament bundle 13, and a rotor 14; the tops of the front baffle 3, the high-pressure fingertip plate 4, the low-pressure fingertip plate 5, and the rear baffle I6 are fixedly connected and installed inside the mounting base 1 through the welding zone I2; the left side of the front baffle 3 is attached to the left side of the interior of the mounting base 1; the right side of the front baffle 3 is attached to the left side of the high-pressure fingertip plate 4; the right side of the high-pressure fingertip plate 4 is attached to the left side of the low-pressure fingertip plate 5; and the upper left side of the rear baffle I6 is attached to the upper right side of the low-pressure fingertip plate 5. The front baffle 3, high-pressure fingertip plate 4, low-pressure fingertip plate 5, and rear baffle I6 form a fingertip sealing structure. A stepped groove is provided on the left side of the rear baffle I6, which forms a stepped cavity I15 with the right side of the low-pressure fingertip plate 5. The brush ring 10 is fixedly connected to the stepped cavity I15 of the rear baffle I6 by screws 11. The brush filament bundle 13 is fixedly connected to the inner diameter of the brush ring 10 by the welding zone II12 to form a brush-type sealing structure. The brush-type sealing structure further reduces sealing leakage and also reduces the volume of the entire sealing structure. The inner diameters of the high-pressure fingertip plate 4, low-pressure fingertip plate 5, and brush filament bundle 13 are all in contact with the rotor 14. The front baffle 3, high-pressure fingertip plate 4, low-pressure fingertip plate 5, rear baffle I6, brush ring 10, screws 11, and brush filament bundle 13 form a first-stage low-hysteresis seal. The structure includes stepped grooves on the left sides of both rear baffles II8 and III9. The inner diameter of the stepped groove in rear baffle III9 is ​​larger than that in rear baffle II8, and the inner diameter of the stepped groove in rear baffle II8 is larger than that in rear baffle I6. The stepped groove in rear baffle II8 and the right side of the low-pressure fingertip 5 form a stepped cavity II17, and the stepped groove in rear baffle III9 and the right side of the low-pressure fingertip 5 form a stepped cavity III18. The front baffle 3, high-pressure fingertip 4, low-pressure fingertip 5, rear baffle II8, brush ring 10, screw 11, and brush filament bundle 13 form a two-stage low-hysteresis sealing structure. The component connection and installation are the same as the first-stage low-hysteresis sealing structure. The partition 7 is installed inside the mounting base 1, and the two-stage low-hysteresis sealing structure is separated from the first-stage low-hysteresis sealing structure by the partition 7. A pressure-bearing cavity 16 is formed between the sealing structure and the first-level low-hysteresis sealing structure. The pressure-bearing cavity 16 is used to bear the upstream pressure. The thickness of the rear baffle I 6, rear baffle II 8, and rear baffle III 9 is greater than that of the front baffle 3. The front baffle 3, high-pressure fingertip plate 4, low-pressure fingertip plate 5, rear baffle III 9, brush ring 10, screw 11, and brush filament bundle 13 form a three-level low-hysteresis sealing structure. Each level of low-hysteresis sealing structure is formed by different rear baffle I 6, rear baffle II 8, and rear baffle III 9, and the front baffle 3, high-pressure fingertip plate 4, low-pressure fingertip plate 5, brush ring 10, screw 11, and brush filament bundle 13. The connection and installation of its components are the same as those of the first-level low-hysteresis sealing structure. It is separated from the front low-hysteresis sealing structure by a partition 7. A pressure-bearing cavity 16 is formed between every two levels of low-hysteresis sealing structures.

[0005] The sizes of the stepped cavity I 15, stepped cavity II 17, and stepped cavity III 18 are adjusted by the stepped groove.

[0006] The first step of the rear baffle I6, rear baffle II8, and rear baffle III9 forms a pressure-reducing chamber with the brush seal structure. The pressure-reducing chamber is used to reduce the contact between the brush bristle bundle 13 and the rear baffle I6, rear baffle II8, and rear baffle III9, thereby reducing the hysteresis effect of the brush seal structure, reducing brush bristle wear and breakage, and improving the sealing performance of the brush seal structure.

[0007] The brush-type sealing structure forms a back pressure cavity with the right side of the low-pressure fingertip piece 5. The back pressure cavity is used to reduce the contact between the low-pressure fingertip piece 5 and the rear baffle I6, thereby reducing the hysteresis effect of the fingertip sealing structure. The size of the back pressure cavity is adjusted by the axial thickness of the brush-type sealing structure. The back pressure cavity is used to reduce the pressure on the fingertip sealing structure, thereby improving the sealing performance of the fingertip seal and protecting the life of the fingertip sealing structure.

[0008] The size of the pressure-bearing cavity 16 is adjusted by the volume of the partition 7. The size of the pressure-bearing cavity 16 is used to adjust the pressure drop of the two-stage sealing structure, so as to improve the pressure-bearing advantage and sealing performance of the overall sealing structure.

[0009] The working principle of a multi-stage low-hysteresis sealing structure with a fingertip-brush composite is as follows: the high-pressure fingertip 4, the low-pressure fingertip 5, and the brush filament bundle 13 are all in contact with the rotor 14. When the rotor 14 rotates, the rotor 14 undergoes radial runout, which pushes the high-pressure fingertip 4, the low-pressure fingertip 5, and the brush filament bundle 13 to move upward. When the high-pressure fingertip 4, the low-pressure fingertip 5, and the brush filament bundle 13 move upward, the stepped grooves in the rear baffles I6, II8, and III9 reduce the contact area between the high-pressure fingertip 4 and the low-pressure fingertip 5, between the low-pressure fingertip 5 and the rear baffles I6, II8, and III9, and between the brush filament bundle and the rear baffles I6, II8, and III9, thereby reducing the hysteresis effect of the sealing structure. Meanwhile, when the upstream gas first passes through the front baffle 3 and the lower part of the high-pressure fingertip plate 4, it resists a large pressure, and the gas leaks through the sealing structure. The leaked gas enters the pressure-bearing cavity 16 between the rear baffle I6 and the secondary low-hysteresis sealing structure. Therefore, the pressure difference on both sides of the primary low-hysteresis sealing structure decreases, and the sealing effect is improved. When the leaked gas passes through the secondary low-hysteresis sealing structure, the high-pressure fingertip plate 4 of the secondary low-hysteresis sealing structure can resist a large pressure, and then the sealing gas gradually decreases, thereby achieving a better sealing effect.

[0010] The present invention has the following beneficial effects: The sealing structure has good adaptability, and by combining fingertip sealing and brush sealing, it can reduce the sealing leakage rate. It can reduce the "hysteresis" effect of multi-stage sealing devices, reduce their leakage rate, have better sealing performance, and also increase the working life of brush seals and fingertip seals; By effectively utilizing the stepped cavity, the overall structure's volume and weight can be reduced. The brush seal is fixedly connected to the brush ring, which can be disassembled using screws.

[0011] It is a modular seal, and the selected brush ring does not need to be manufactured separately. It has a simple structure, low manufacturing cost, and is easy to promote and apply. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of the present invention.

[0013] The labels in the diagram are as follows: 1: Mounting base, 2: Welding zone I, 3: Front baffle 3, 4: High-pressure fingertip plate, 5: Low-pressure fingertip plate, 6: Rear baffle I, 7: Partition plate, 8: Rear baffle II, 9: Rear baffle III, 10: Brush ring, 11: Screw, 12: Welding zone II, 13: Brush filament bundle, 14: Rotor, 15: Stepped cavity I, 16: Pressure bearing cavity, 17: Stepped cavity II, 18: Stepped cavity III. Detailed Implementation

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments, but the scope of the present invention is not limited to the description.

[0015] Example 1: As Figure 1As shown, a multi-stage low-hysteresis sealing structure of fingertip-brush composite includes a mounting base 1, a welding zone I 2, a front baffle 3, a high-pressure fingertip plate 4, a low-pressure fingertip plate 5, a rear baffle I 6, a partition 7, a rear baffle II 8, a brush ring 10, a screw 11, a welding zone II 12, a brush filament bundle 13, and a rotor 14. The tops of the front baffle 3, the high-pressure fingertip plate 4, the low-pressure fingertip plate 5, and the rear baffle I 6 are fixedly connected and installed inside the mounting base 1 through the welding zone I 2. The left side of the front baffle 3 is fitted against the left side of the interior of the mounting base 1, and the right side of the front baffle 3 is fitted against the high-pressure fingertip plate. 4. The left side of the high-pressure fingertip 4 is attached to the left side of the low-pressure fingertip 5, and the upper left side of the rear baffle I6 is attached to the upper right side of the low-pressure fingertip 5. The front baffle 3, high-pressure fingertip 4, low-pressure fingertip 5, and rear baffle I6 form a fingertip sealing structure. A stepped groove is provided on the left side of the rear baffle I6. The stepped groove of the rear baffle I6 and the right side of the low-pressure fingertip 5 form a stepped cavity I15. The brush filament bundle 13 is fixedly connected to the inner diameter of the brush ring 10 through the welding zone II12 to form a brush-type sealing structure. The brush ring 10 is fixedly connected to the stepped cavity I15 of the rear baffle I6 by screws 11. Within 15, the brush-type sealing structure further reduces sealing leakage and also reduces the overall volume of the sealing structure. The inner diameter of the high-pressure fingertip 4, low-pressure fingertip 5, and brush filament bundle 13 all contact the rotor 14. The front baffle 3, high-pressure fingertip 4, low-pressure fingertip 5, rear baffle I 6, brush ring 10, screw 11, and brush filament bundle 13 form a first-stage low-hysteresis sealing structure. The left side of the rear baffle II 8 is also provided with stepped grooves. The inner diameter of the stepped groove of the rear baffle II 8 is larger than that of the stepped groove of the rear baffle I 6. The stepped groove of the rear baffle II 8 and the right side of the low-pressure fingertip 5 form a stepped cavity II 1. 7. The front baffle 3, high-pressure fingertip plate 4, low-pressure fingertip plate 5, rear baffle II 8, brush ring 10, screw 11, and brush filament bundle 13 form a two-stage low-hysteresis sealing structure. The connection and installation of its components are the same as those of the first-stage low-hysteresis sealing structure. The partition 7 is installed inside the mounting base 1. The two-stage low-hysteresis sealing structure is separated from the first-stage low-hysteresis sealing structure by the partition 7. A pressure-bearing cavity 16 is formed between the two-stage low-hysteresis sealing structure and the first-stage low-hysteresis sealing structure. The pressure-bearing cavity 16 is used to bear the upstream pressure. The thickness of the rear baffle I 6 and the rear baffle II 8 is greater than that of the front baffle 3.

[0016] Example 2: Figure 1As shown, a multi-stage low-hysteresis sealing structure of fingertip-brush composite includes a mounting base 1, a welding zone I2, a front baffle 3, a high-pressure fingertip plate 4, a low-pressure fingertip plate 5, a rear baffle I6, a partition 7, a rear baffle II 8, a rear baffle III 9, a brush ring 10, a screw 11, a welding zone II 12, a brush filament bundle 13, and a rotor 14. The tops of the front baffle 3, the high-pressure fingertip plate 4, the low-pressure fingertip plate 5, and the rear baffle I6 are fixedly connected and installed inside the mounting base 1 through the welding zone I2. The left side of the front baffle 3 is attached to the left side of the interior of the mounting base 1, the right side of the front baffle 3 is attached to the left side of the high-pressure fingertip plate 4, the right side of the high-pressure fingertip plate 4 is attached to the left side of the low-pressure fingertip plate 5, and the upper left side of the rear baffle I6 is attached to the low-pressure fingertip plate 5. The upper right side of plate 5 is fitted together. The front baffle 3, high-pressure fingertip plate 4, low-pressure fingertip plate 5, and rear baffle I6 form a fingertip sealing structure. A stepped groove is opened on the left side of the rear baffle I6. The stepped groove of the rear baffle I6 and the right side of the low-pressure fingertip plate 5 form a stepped cavity I15. The brush filament bundle 13 is fixedly connected to the inner diameter of the brush ring 10 through the welding zone II12 to form a brush-type sealing structure. The brush ring 10 is fixedly connected to the stepped cavity I15 of the rear baffle I6 by screws 11. The brush-type sealing structure further reduces sealing leakage and also reduces the volume of the entire sealing structure. The inner diameter of the high-pressure fingertip plate 4, low-pressure fingertip plate 5, and brush filament bundle 13 are all in contact with the rotor 14. The front baffle 3, high-pressure fingertip plate 4, low-pressure fingertip plate 5, and rear baffle I6 are all in contact with the rotor 14. I6, brush ring 10, screw 11, and brush filament bundle 13 form a primary low-hysteresis sealing structure. Stepped grooves are also provided on the left side of rear baffles II8 and III9. The inner diameter of the stepped groove in rear baffle III9 is ​​larger than that in rear baffle II8, and the inner diameter of the stepped groove in rear baffle II8 is larger than that in rear baffle I6. The stepped groove in rear baffle II8 and the right side of the low-pressure fingertip 5 form a stepped cavity II17, and the stepped groove in rear baffle III9 and the right side of the low-pressure fingertip 5 form a stepped cavity III18. The front baffle 3, high-pressure fingertip 4, low-pressure fingertip 5, rear baffle II8, brush ring 10, screw 11, and brush filament bundle 13 form a secondary low-hysteresis sealing structure. The connection and installation of its components are the same as the primary low-hysteresis sealing structure. The partition 7 is installed inside the mounting base 1. The secondary low-hysteresis sealing structure is separated from the primary low-hysteresis sealing structure by the partition 7. A pressure-bearing cavity 16 is formed between the secondary low-hysteresis sealing structure and the primary low-hysteresis sealing structure. The pressure-bearing cavity 16 is used to bear the upstream pressure. The thickness of the rear baffle I 6, rear baffle II 8, and rear baffle III 9 is greater than that of the front baffle 3. The front baffle 3, high-pressure fingertip plate 4, low-pressure fingertip plate 5, rear baffle III 9, brush ring 10, screw 11, and brush filament bundle 13 form a tertiary low-hysteresis sealing structure. The connection and installation of its components are the same as those of the primary low-hysteresis sealing structure. It is separated from the front low-hysteresis sealing structure by the partition 7. A pressure-bearing cavity 16 is formed between every two low-hysteresis sealing structures.

Claims

1. A multi-stage low-hysteresis sealing structure with a fingertip-brush composite feature, characterized in that: The components include a mounting base (1), welding zone I (2), a front baffle (3), a high-voltage fingertip plate (4), a low-voltage fingertip plate (5), a rear baffle I (6), a partition (7), a rear baffle II (8), a rear baffle III (9), a brush ring (10), a screw (11), welding zone II (12), a brush filament bundle (13), and a rotor (14). The tops of the front baffle (3), the high-voltage fingertip plate (4), the low-voltage fingertip plate (5), and the rear baffle I (6) are fixedly connected to the inside of the mounting base (1) via welding zone I (2). The left side of the front baffle (3) is attached to the left side of the inside of the mounting base (1), the right side of the front baffle (3) is attached to the left side of the high-voltage fingertip plate (4), and the right side of the high-voltage fingertip plate (4) is attached to the left side of the low-voltage fingertip plate (5). The upper left side of baffle I (6) is attached to the upper right side of the low-pressure fingertip plate (5). The front baffle (3), high-pressure fingertip plate (4), low-pressure fingertip plate (5), and rear baffle I (6) form a fingertip sealing structure. A stepped groove is provided on the left side of the rear baffle I (6). The stepped groove of the rear baffle I (6) and the right side of the low-pressure fingertip plate (5) form a stepped cavity I (15). The brush ring (10) is fixedly connected to the stepped cavity I (15) of the rear baffle I (6) by screws (11). The brush filament bundle (13) is fixedly connected to the inner diameter of the brush ring (10) through the welding zone II (12) to form a brush-type sealing structure. The inner diameter of the high-pressure fingertip plate (4), low-pressure fingertip plate (5), and brush filament bundle (13) are all in contact with the rotor (14). The front baffle (3) and the high-pressure fingertip plate (4) The low-pressure fingertip piece (5), the rear baffle I (6), the brush ring (10), the screw (11), and the brush filament bundle (13) form a first-level low-hysteresis sealing structure. The left side of the rear baffle II (8) and the rear baffle III (9) are also provided with stepped grooves. The inner diameter of the stepped groove of the rear baffle III (9) is larger than that of the stepped groove of the rear baffle II (8). The inner diameter of the stepped groove of the rear baffle II (8) is larger than that of the stepped groove of the rear baffle I (6). The stepped groove of the rear baffle II (8) and the right side of the low-pressure fingertip piece (5) form a stepped cavity II (17). The stepped groove of the rear baffle III (9) and the right side of the low-pressure fingertip piece (5) form a stepped cavity III (18). The front baffle (3), the high-pressure fingertip piece (4), the low-pressure fingertip piece (5), the rear baffle II (8), and the brush ring (10) are also provided. Screws (11) and brush filament bundles (13) form a secondary low-hysteresis sealing structure. The component connection and installation are the same as those of the primary low-hysteresis sealing structure. A partition (7) is installed inside the mounting base (1). The secondary low-hysteresis sealing structure is separated from the primary low-hysteresis sealing structure by the partition (7). A pressure-bearing cavity (16) is formed between the secondary low-hysteresis sealing structure and the primary low-hysteresis sealing structure. The pressure-bearing cavity (16) is used to bear the upstream pressure. The thickness of the rear baffle I (6), rear baffle II (8), and rear baffle III (9) is greater than that of the front baffle (3). The front baffle (3), high-pressure fingertip plate (4), low-pressure fingertip plate (5), rear baffle III (9), brush ring (10), screws (11), and brush filament bundles (13) form a tertiary low-hysteresis sealing structure.Each stage of the low-hysteresis sealing structure is formed by different rear baffles I (6), II (8), III (9), and front baffle (3), high-pressure fingertip plate (4), low-pressure fingertip plate (5), brush ring (10), screws (11), and brush filament bundle (13). The connection and installation of these components are the same as the first-stage low-hysteresis sealing structure. They are separated from the front low-hysteresis sealing structure by a partition (7), and a pressure-bearing cavity (16) is formed between every two stages of the low-hysteresis sealing structure.

2. The multi-stage low-hysteresis sealing structure of fingertip-brush composite according to claim 1, characterized in that: The sizes of the stepped cavity I (15), stepped cavity II (17), and stepped cavity III (18) are adjusted by the stepped groove.

3. The multi-stage low-hysteresis sealing structure of fingertip-brush composite according to claim 1, characterized in that: The first step of the rear baffle I (6), rear baffle II (8), and rear baffle III (9) forms a pressure relief chamber with the brush seal structure. The pressure relief chamber is used to reduce the contact between the brush filament bundle (13) and the rear baffle I (6), rear baffle II (8), and rear baffle III (9), respectively, thereby reducing the hysteresis effect of the brush seal structure, reducing brush filament wear and breakage, and improving the sealing performance of the brush seal structure.

4. The multi-stage low-hysteresis sealing structure of fingertip-brush composite according to claim 1, characterized in that: The size of the pressure chamber (16) is adjusted by the volume of the partition (7).

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