Brush type-labyrinth parallel sealing structure used between stages of gas turbine
By adopting a brush-labyrinth parallel sealing structure between gas turbine stages, combining a three-stage brush seal with a two-stage labyrinth seal, the problems of large space occupation and large leakage of traditional sealing structures are solved, achieving a compact and efficient sealing effect.
Patent Information
- Application Number
- CN202520855536.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-30
- Publication Date
- 2026-02-17
- Estimated Expiration
- 2035-04-30
AI Technical Summary
Traditional tandem brush seal structures occupy large axial and radial dimensions, and labyrinth seals have large leakage under high pressure differentials or high-speed rotation, which cannot meet the requirements for high sealing performance.
It adopts a brush-labyrinth parallel sealing structure, combining a three-stage brush seal with a two-stage labyrinth seal to form a five-stage seal, reducing axial dimensions, enhancing sealing performance, and adapting to higher working pressures.
It achieves a more compact sealing structure, reduces leakage, improves sealing performance, is suitable for high pressure differential and high speed rotation conditions, and is easy to install and disassemble.
Smart Images
Figure CN223923829U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the technical field of sealing structure, especially relates to a brush -labyrinth parallel sealing structure for gas turbine interstage, is applicable to the occasion of extremely high sealing performance requirement. BACKGROUND
[0002] In the field of energy, petroleum chemical industry and aviation, gas turbine is widely used, and sealing technology is very important in gas turbine, which directly affects the performance, efficiency, reliability and safety of equipment. At present, gas turbine mainly uses brush seal and labyrinth seal.
[0003] Brush seal is a kind of high-efficiency flexible contact sealing technology, and brush seal is mainly composed of front baffle, rear baffle and high-density brush bundle between the two. Brush bundle is usually made of cobalt-based superalloy, which has good flexibility and elasticity. Brush silk has a certain inclination along the rotating direction of rotor, which can absorb the radial displacement and axial movement of rotor. When fluid enters the brush bundle, due to the unevenness of the gap between the brush filaments, the fluid flow becomes uneven, forming co-flow, jet and random secondary flow and vortex flow. These complex flow patterns convert the kinetic energy of fluid into heat energy, and increase the total pressure drop of fluid, thereby reducing leakage. In order to further improve the sealing performance, multi-stage brush seal structure is developed, but the traditional series brush multi-stage sealing structure occupies larger axial and radial size and has low working pressure.
[0004] Labyrinth seal is a kind of non-contact sealing technology, which is widely used in rotary machinery, such as shaft end and interstage seal of steam turbine, gas turbine, compressor and other equipment. The core principle of labyrinth seal is to use the throttling and expansion effect of fluid in the sealing channel to increase the flow resistance of fluid, thereby reducing the leakage. Labyrinth seal is a non-contact seal, which will not cause wear to the rotor, has long service life and is suitable for various pressure, temperature and medium working conditions, but labyrinth seal cannot completely eliminate leakage, especially in high pressure difference or high speed rotating working condition, the leakage may be large, and multi-stage labyrinth seal needs larger installation space. UTILITY MODEL CONTENTS
[0005] The utility model aims at solving the defects existing in the prior art, and provides a brush-labyrinth parallel sealing structure for gas turbine interstage, which aims at solving the sealing problem in the above background technology. The brush-labyrinth parallel sealing structure is more compact than the traditional direct series multi-stage brush seal and labyrinth seal structure, and fully utilizes the respective advantages of brush seal and labyrinth seal, and can withstand higher working pressure.
[0006] The utility model adopts the following technical scheme:
[0007] A brush-labyrinth parallel sealing structure for gas turbine inter-stage, comprising a rotating shaft, a stepped shaft sleeve, a third-stage brush seal ring, a second-stage brush seal ring, a first-stage brush seal ring and an end cover. The third-stage brush seal ring, the second-stage brush seal ring and the first-stage brush seal ring are respectively installed on the stepped end faces formed by the stepped shaft sleeve and the end cover, forming a brush seal and a labyrinth seal structure. The end face of the end cover in contact with the rotating shaft and the end face of the stepped shaft sleeve in contact with the rotating shaft are both installed with an O-shaped sealing ring. The stepped shaft sleeve is fixed on the rotating shaft through a set screw.
[0008] Further, the third-stage brush seal ring is composed of a third-stage brush seal rear baffle, a third-stage brush seal ring front baffle, a third-stage fusion welding area and third-stage brush wires. The left side of the third-stage fusion welding area is welded to the third-stage brush seal rear baffle, the right side of the third-stage fusion welding area is welded to the third-stage brush seal ring front baffle, and one end of the third-stage brush wires is welded to the third-stage fusion welding area, and the free end of the third-stage brush wires is exposed outside the cavity.
[0009] Further, the third-stage brush seal rear baffle is in contact with the end cover step, the third-stage brush seal ring front baffle is in contact with the second-stage brush seal ring rear baffle, the third-stage brush seal ring third-stage fusion welding area is in contact with the end cover step, the free end of the third-stage brush wires on the third-stage brush seal ring is in contact with the third-stage coating area of the stepped shaft sleeve, forming a third-stage brush seal, and the part of the third-stage brush seal ring front baffle with rectangular teeth is in contact with the part of the stepped shaft sleeve first end face with rectangular teeth, forming a second-stage labyrinth seal.
[0010] Further, the second-stage brush seal ring is composed of a second-stage brush seal ring front baffle, a second-stage fusion welding area, a second-stage brush seal rear baffle and second-stage brush wires. The left side of the second-stage fusion welding area is welded to the second-stage brush seal rear baffle, the right side of the second-stage fusion welding area is welded to the second-stage brush seal front baffle, and one end of the second-stage brush wires is welded to the second-stage fusion welding area, and the free end of the second-stage brush wires is exposed outside the cavity.
[0011] Further, the second-stage brush seal ring rear baffle is in contact with the end cover step, the second-stage brush seal ring front baffle is in contact with the first-stage brush seal ring rear baffle, the free end of the second-stage brush wires on the second-stage brush seal ring is in contact with the second-stage coating area of the stepped shaft sleeve, forming a second-stage brush seal, and the part of the second-stage brush seal ring front baffle with rectangular teeth is in contact with the part of the stepped shaft sleeve first end face with rectangular teeth, forming a first-stage labyrinth seal.
[0012] Further, the first-stage brush seal ring is composed of a first-stage brush seal ring front baffle, a first-stage fusion welding area, a first-stage brush seal rear baffle and first-stage brush wires. The left side of the first-stage fusion welding area is welded to the first-stage brush seal rear baffle, the right side of the first-stage fusion welding area is welded to the first-stage brush seal front baffle, and one end of the first-stage brush wires is welded to the first-stage fusion welding area, and the free end of the first-stage brush wires is exposed outside the cavity.
[0013] Further, the rear baffle of the first brush seal contacts with the stepped end cover, the front baffle of the first brush seal ring contacts with the baffle ring, and the free end of the first brush wire of the first brush seal ring forms the first brush seal with the first coating area of the stepped shaft sleeve.
[0014] The stepped shaft sleeve is axially positioned by the shaft shoulder at the right end of the rotating shaft.
[0015] Further, the thickness of the first brush wire, the second brush wire and the third brush wire is 3.2mm, the thickness of the front baffle of the first brush seal ring, the front baffle of the second brush seal ring and the front baffle of the third brush seal ring is 2mm, and the rear baffle of the first brush seal ring, the rear baffle of the second brush seal ring and the rear baffle of the third brush seal ring form pressure cavities with the brush wires respectively.
[0016] Further, the axial height of the rectangular teeth of the front baffle of the second brush seal ring, the front baffle of the third brush seal ring and the rectangular teeth of the end face of the stepped shaft sleeve (the first end face of the stepped shaft sleeve and the second end face of the stepped shaft sleeve) is 1.8mm, the radial thickness is 1mm, and the radial distance of the rectangular teeth of the front baffle of the second brush seal ring, the front baffle of the third brush seal ring and the rectangular teeth of the end face of the stepped shaft sleeve (the first end face of the stepped shaft sleeve and the second end face of the stepped shaft sleeve) is 3mm.
[0017] Further, the front baffle of the third brush seal ring is connected with the rear baffle of the second brush seal ring and the front baffle of the second brush seal ring is connected with the rear baffle of the first brush seal ring through profile connection.
[0018] Further, the end cover is connected with the box body through bolts.
[0019] The utility model discloses beneficial effect:
[0020] The utility model discloses adopt three -level brush seal and two -level labyrinth seal parallelly, relative to the brush seal and the labyrinth seal direct series connection along the axis, reduce the axial dimension, three -level brush seal and two -level labyrinth seal common constitute five -level seal, can bear higher sealed medium pressure therefore, reduce the leakage, and each level brush seal ring is a whole, and the relative party is convenient to assemble and disassemble. DRAWINGS
[0021] Figure 1 It is whole structure schematic diagram of the utility model.
[0022] Figure 2 It is first brush seal ring structure schematic diagram of the utility model.
[0023] Figure 3 It is second brush seal ring structure schematic diagram of the utility model.
[0024] Figure 4 It is the schematic diagram of the three-stage brush type sealing ring structure of the utility model.
[0025] Figure 5 It is the schematic diagram of the stepped shaft sleeve structure of the utility model.
[0026] In the drawing: 1-rotating shaft, 2-o type sealing ring, 3-tightening screw, 4-stepped shaft sleeve, 5-three-stage brush type sealing ring, 6-two-stage brush type sealing ring, 7-one-stage brush type sealing ring, 8-retainer ring, 9-box body, 10-bolt, 11-end cover;
[0027] 40-one-stage coating area, 41-two-stage coating area, 42-three-stage coating area;
[0028] 50-front baffle of the three-stage brush type sealing ring, 51-three-stage fusion welding area, 52-rear baffle of the three-stage brush type sealing, 53-three-stage brush wire;
[0029] 60-front baffle of the two-stage brush type sealing ring, 61-two-stage fusion welding area, 62-rear baffle of the two-stage brush type sealing, 63-two-stage brush wire;
[0030] 70-front baffle of the one-stage brush type sealing ring, 71-one-stage fusion welding area, 72-rear baffle of the one-stage brush type sealing, 73-one-stage brush wire. DETAILED DESCRIPTION
[0031] In order to make the purpose, technical scheme and advantages of the utility model more clear, the technical scheme in the utility model is described clearly and completely below, obviously, the described embodiment is a part of the embodiment of the utility model, rather than all the embodiments. Based on the embodiment in the utility model, all other embodiments obtained by the person skilled in the art without making the creative labor belong to the protection scope of the utility model.
[0032] As shown in Figure 1 The utility model discloses a brush type -labyrinth parallel sealing structure for gas turbine interstage, including rotating shaft 1, o type sealing ring 2, tightening screw 3, stepped shaft sleeve 4, three-stage brush type sealing ring 5, two-stage brush type sealing ring 6, one-stage brush type sealing ring 7, retainer ring 8, box body 9, bolt 10 and end cover 11.
[0033] As shown in Figure 4 Three-stage brush type sealing ring 5, rear baffle of three-stage brush type sealing 52, front baffle of three-stage brush type sealing ring 50, three-stage fusion welding area 51 and three-stage brush wire 53 are connected by welding, three-stage fusion welding area 51 left side is connected with rear baffle of three-stage brush type sealing 52 by welding, three-stage fusion welding area 51 right side is connected with front baffle of three-stage brush type sealing ring 50 by welding, one end of three-stage brush wire 53 is connected in three-stage fusion welding area 51, and three-stage brush wire free end exposes cavity outside.
[0034] As shown in Figure 1 , Figure 4 , Figure 5 , the rear baffle 52 of the third brush seal is in stepped contact with the end cover 11 for axial positioning, the front baffle 50 of the third brush seal ring is in profile contact with the rear baffle 62 of the second brush seal ring for circumferential positioning, the third fusion welding area 51 of the third brush seal ring 5 is in stepped contact with the end cover 11, the free end of the third brush wire 51 on the third brush seal ring 5 is in contact with the third coating area 42 of the stepped shaft sleeve 4 to form the third brush seal, and the part with rectangular teeth of the front baffle 50 of the third brush seal ring forms the second labyrinth seal with the second end face of the stepped shaft sleeve 4.
[0035] As shown in Figure 3 , the second brush seal ring 6 includes the front baffle 60 of the second brush seal ring, the second fusion welding area 61, the rear baffle 62 of the second brush seal, and the second brush wire 63. The left side of the second fusion welding area 61 is welded to the rear baffle 62 of the second brush seal, the right side of the second fusion welding area 61 is welded to the front baffle 60 of the second brush seal, one end of the second brush wire 63 is welded to the second fusion welding area 61, and the free end of the second brush wire is exposed outside the cavity.
[0036] As shown in Figure 1 , Figure 3 , Figure 5 , the rear baffle 62 of the second brush seal ring is in stepped contact with the end cover 11 for axial positioning, the front baffle 60 of the second brush seal ring is in profile contact with the rear baffle 72 of the first brush seal ring for circumferential positioning, the free end of the second brush wire 63 on the second brush seal ring 6 forms the second brush seal with the second coating area 41 of the stepped shaft sleeve 4, and the part with rectangular teeth of the front baffle 60 of the second brush seal ring forms the first labyrinth seal with the first end face of the stepped shaft sleeve 4.
[0037] As shown in Figure 2 , the first brush seal ring 7 includes the front baffle 70 of the first brush seal ring, the first fusion welding area 71, the rear baffle 72 of the first brush seal, and the first brush wire 73. The left side of the first fusion welding area 71 is welded to the rear baffle 72 of the first brush seal, the right side of the first fusion welding area 71 is welded to the front baffle 70 of the first brush seal, one end of the first brush wire 73 is welded to the first fusion welding area 71, and the free end of the first brush wire 73 is exposed outside the cavity.
[0038] As shown in Figure 1 , Figure 2 , Figure 5As shown, the rear baffle 72 of the primary brush seal is in stepped contact with the end cover 11 to axially position, and the front baffle 70 of the primary brush seal ring is in contact with the baffle ring 8 to axially position. The free end of the primary brush wire 73 on the primary brush seal ring 7 forms the first brush seal with the primary coating area 40 of the stepped shaft sleeve 4.
[0039] As shown, the stepped shaft sleeve 4 includes the third coating area 42 in contact with the free end of the third brush wire 53, the second coating area 41 in contact with the free end of the second brush wire 63, and the primary coating area 40 in contact with the free end of the primary brush wire 73. Figure 5
[0040] The stepped shaft sleeve 4 is axially positioned with the shaft shoulder at the right end of the rotating shaft 1, and is connected with the rotating shaft 1 through the set screw 3 at the left end to realize the circumferential positioning of the stepped shaft sleeve 4. The primary brush wire 73, the second brush wire 63 and the third brush wire 53 are welded on the brush seal rings of the respective levels away from the shaft end, and the other ends are in contact with the stepped shaft sleeve 4 which is driven to move circumferentially. The rectangular teeth on the first end face and the second end face of the stepped shaft sleeve form the labyrinth seal channel with the rectangular teeth on the front baffles 60 and 50 of the second brush seal ring and the third brush seal ring respectively.
[0041] The thickness of the primary brush wire 73, the second brush wire 63 and the third brush wire 53 is 3.2mm; the thickness of the front baffles 70, 60 and 50 of the primary brush seal ring, the second brush seal ring and the third brush seal ring is 2mm; the rear baffles 72, 62 and 52 of the primary brush seal ring, the second brush seal ring and the third brush seal ring respectively form the pressure cavity with the brush wires of the respective levels.
[0042] The axial height of the rectangular teeth on the front baffles 60 and 50 of the second brush seal ring and the third brush seal ring and the rectangular teeth on the end face of the stepped shaft sleeve 4 is 1.8mm, and the radial thickness is 1mm; the radial spacing of the rectangular teeth on the front baffles and the end face of the stepped shaft sleeve 4 is 3mm.
[0043] Specifically, the front baffle 50 of the third brush seal ring is connected with the rear baffle 62 of the second brush seal ring and the front baffle 60 of the second brush seal ring is connected with the rear baffle 72 of the primary brush seal ring through the profile to realize the radial positioning of the third brush seal ring.
[0044] Further, the end of the end cover 11 in contact with the rotating shaft 1 and the end of the stepped shaft sleeve 4 in contact with the rotating shaft 1 are both provided with an o-shaped sealing ring.
[0045] Further, the end cover 11 is connected with the box body 9 through the bolt 10.
[0046] The working process of the utility model is as follows:
[0047] When the rotor 1 rotates, the first-stage brush wire 73, the second-stage brush wire 63 and the third-stage brush wire 53 gradually adhere to the surface of the stepped shaft sleeve 4 to form a tight contact under the action of friction force, and first-stage, second-stage and third-stage brush sealings are formed, respectively. Meanwhile, the portion with rectangular teeth of the front baffle 60 of the second-stage brush sealing ring forms a first-stage labyrinth sealing with the first end surface of the stepped shaft sleeve 4, and the portion with rectangular teeth of the front baffle 50 of the third-stage brush sealing ring forms a second-stage labyrinth sealing with the second end surface of the stepped shaft sleeve 4. The sealing medium passes through each stage of brush sealings and labyrinth sealings with throttling and self-sealing properties in sequence. Specifically, the sealing medium is blocked to pass through the first-stage brush sealing, the first-stage labyrinth sealing, the second-stage brush sealing, the second-stage labyrinth sealing and the third-stage brush sealing in sequence, so that the required sealing performance is achieved.
[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced equivalently. These modifications or replacements do not change the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A brush-labyrinth parallel seal structure for use in a gas turbine inter-stage, characterized by, The utility model discloses a rotating shaft, ladder shaft sleeve, three level brush type sealing ring, two level brush type sealing ring, one level brush type sealing ring and end cover, three level brush type sealing ring, two level brush type sealing ring and one level brush type sealing ring are installed on the end face formed by ladder shaft sleeve and end cover respectively, form the brush type sealing and labyrinth seal structure, and the end face of end cover and rotating shaft contact, and the end face of ladder shaft sleeve and rotating shaft contact all are installed with o type sealing ring, and ladder shaft sleeve is fixed on rotating shaft through set screw.
2. The parallel seal structure according to claim 1, wherein The three level brush type sealing ring is composed of a rear baffle of the three level brush type sealing, a front baffle of the three level brush type sealing ring, a three level welding area and three level brush wires, the left side of the three level welding area is welded and connected with the rear baffle of the three level brush type sealing, the right side of the three level welding area is welded and connected with the front baffle of the three level brush type sealing ring, one end of the three level brush wires is welded and connected with the three level welding area, and the free end of the three level brush wires is exposed outside the cavity.
3. The parallel seal structure of claim 2, wherein, The rear baffle of the three level brush type sealing is in contact with the ladder of the end cover, the front baffle of the three level brush type sealing ring is in contact with the rear baffle of the two level brush type sealing ring, the three level welding area of the three level brush type sealing ring is in contact with the ladder of the end cover, the free end of the three level brush wires on the three level brush type sealing ring is in contact with the three level coating area of the ladder shaft sleeve, to form the third level brush type sealing, and the part with rectangular teeth of the front baffle of the three level brush type sealing ring is in contact with the part with rectangular teeth of the second end face of the ladder shaft sleeve, to form the second level labyrinth seal.
4. The parallel seal structure of claim 1, wherein The two level brush type sealing ring is composed of a front baffle of the two level brush type sealing ring, a two level welding area, a rear baffle of the two level brush type sealing and two level brush wires, the left side of the two level welding area is welded and connected with the rear baffle of the two level brush type sealing, the right side of the two level welding area is welded and connected with the front baffle of the two level brush type sealing, one end of the two level brush wires is welded and connected with the two level welding area, and the free end of the two level brush wires is exposed outside the cavity.
5. The parallel seal structure of claim 4, wherein, The rear baffle of the two level brush type sealing ring is in contact with the ladder of the end cover, the front baffle of the two level brush type sealing ring is in contact with the rear baffle of the one level brush type sealing ring, the free end of the two level brush wires on the two level brush type sealing ring is in contact with the two level coating area of the ladder shaft sleeve, to form the second level brush type sealing, and the part with rectangular teeth of the front baffle of the two level brush type sealing ring is in contact with the part with rectangular teeth of the first end face of the ladder shaft sleeve, to form the first level labyrinth seal.
6. The parallel seal structure of claim 1, wherein The left side of the one level welding area is welded and connected with the rear baffle of the one level brush type sealing, the right side of the one level welding area is welded and connected with the front baffle of the one level brush type sealing, one end of the one level brush wires is welded and connected with the one level welding area, and the free end of the one level brush wires is exposed outside the cavity.
7. The parallel seal structure of claim 6, wherein The rear baffle of the one level brush type sealing is in contact with the ladder of the end cover, the front baffle of the one level brush type sealing ring is in contact with the baffle ring, and the free end of the one level brush wires on the one level brush type sealing ring is in contact with the one level coating area of the ladder shaft sleeve, to form the first level brush type sealing.
8. The parallel seal structure according to any one of claims 1 to 7, wherein The front baffle of the three level brush type sealing ring is connected with the rear baffle of the two level brush type sealing ring, and the front baffle of the two level brush type sealing ring is connected with the rear baffle of the one level brush type sealing ring through the profile.