CN109555564B - Brush type sealing structure with magnet and adjustable radial gap between brush filament bundle and rotor surface - Google Patents
Brush type sealing structure with magnet and adjustable radial gap between brush filament bundle and rotor surface Download PDFInfo
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- CN109555564B CN109555564B CN201910071749.8A CN201910071749A CN109555564B CN 109555564 B CN109555564 B CN 109555564B CN 201910071749 A CN201910071749 A CN 201910071749A CN 109555564 B CN109555564 B CN 109555564B
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- brush
- type sealing
- brush type
- stator
- sealing element
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D11/00—Preventing or minimising internal leakage of working-fluid, e.g. between stages
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2240/00—Components
- F05D2240/55—Seals
Abstract
The invention discloses a brush type sealing structure containing magnets and capable of adjusting radial gaps between brush filament bundles and a rotor surface, which comprises the following components: the brush type sealing piece is matched with the inner periphery of the stator and can move along the radial direction of the rotor at the inner side of the stator, the brush type sealing piece comprises an upper brush type sealing piece and a lower brush type sealing piece, the upper brush type sealing piece and the lower brush type sealing piece comprise front baffle plates, fusion welding areas, rear baffle plates and brush filament bundles, bolts are fixed in the middle of the outer periphery of the upper brush type sealing piece and the middle of the outer periphery of the lower brush type sealing piece, the bolts pass through matched through holes in the stator and are screwed through nuts, the tile type magnets are arranged in pairs and repel each other, and each pair of tile type magnets comprises a tile type magnet fixed on the outer periphery of the brush type sealing piece and a tile type magnet fixed on the inner periphery of the stator. According to the brush type sealing structure, the adjustment of the radial clearance between brush tows and the rotor surface can be realized by loosening or tightening the nuts, and the uniformly distributed tile-shaped magnets can ensure the stable rotation of the rotor.
Description
Technical Field
The invention relates to a sealing structure applied to rotary machinery, in particular to a brush type sealing structure containing magnets and capable of adjusting radial clearance between brush filament bundles and a rotor surface.
Background
Brush seals are key components of rotary machines such as aircraft engines, steam turbines, compressors, and the like. Compared with the traditional labyrinth seal, the brush seal has good sealing property, can adapt to instantaneous radial deformation or eccentric movement of the rotor, and in addition, brush wires of the brush seal form flexible contact with the rotor, so that the vibration property of a rotor system can be improved, and the running safety of a unit is ensured, therefore, the brush seal is widely applied to rotary machines in the fields of aerospace, electric power, petrochemical industry and the like.
The brush type seal consists of a front panel, a rear panel and brush filament bundles formed by highly dense alloy fine metal wires clamped between the front panel and the rear panel, wherein the brush filament bundles have a certain inclination along the rotation direction of a rotor, the inclined brush filament bundles can allow the rotor to radially jump, after the brush type seal is in interference contact with the rotor, permanent performance loss can not occur like labyrinth seal and honeycomb seal, the brush filament bundles of the brush type seal are regularly arranged according to a certain inclination angle relative to the rotation direction of the rotor, abrasion of the brush filament bundles can be reduced, the brush filament bundles are more easily adapted to manufacturing errors, thermal deformation and the like of the rotor, and the brush filament bundles quickly rebound after the rotor is radially displaced in a moment, so that a sealing gap is kept unchanged. Research shows that the brush type seal is used as a contact type dynamic seal, and the flexibility of the brush filament bundles ensures that the brush filament bundles can present yielding property and following property when the rotor instantaneously jumps radially.
However, the brush filament bundle and the rotor in interference fit have collision friction in the use process, and a larger gap is generated between the brush filament bundle and the rotor surface along with the increase of the use time of the sealing structure, so that the leakage amount is increased, and sealing failure is caused, so that a new brush type sealing element needs to be replaced in time.
In view of this, how to improve current brush seal structure for can adjust the radial clearance between brush silk bundle and the rotor face under the circumstances of not changing the brush silk sealing member, with the sealing performance that improves brush seal, reduce use cost, become the problem that needs to be solved urgently.
Disclosure of Invention
In view of the above, the present invention aims to provide a brush seal structure with a magnet capable of adjusting the radial gap between brush filament bundles and a rotor surface, so as to solve the problem that the gap between brush filament bundles and the rotor surface of the existing brush seal structure cannot be adjusted.
The technical scheme provided by the invention is as follows: a brush seal structure having magnets for adjusting the radial gap between brush filaments and a rotor face, comprising: the brush type sealing element comprises an upper brush type sealing element and a lower brush type sealing element which are arranged in a gap mode and have the same structure, the upper brush type sealing element and the lower brush type sealing element comprise a front baffle, a fusion welding area, a rear baffle and brush filament bundles, the front baffle and the rear baffle are connected through the fusion welding area, the root parts of the brush filament bundles are fixed on the fusion welding area, the free ends are attached to the rotor, bolts are fixed in the middle parts of the outer circumferences of the upper brush type sealing element and the lower brush type sealing element, the bolts penetrate through holes in the stator and are screwed with the bolts, the gap between the upper brush type sealing element and the lower brush type sealing element can be adjusted through rotating nuts, the tile type magnets fixed on the outer circumferences of the brush type sealing element and the tile type magnets fixed on the inner circumferences of the stator are connected through the fusion welding area, and the tile type magnets fixed on the outer circumferences of the stator are uniformly arranged on the peripheries of the brush type sealing element, and the gap between the tile type magnets and the tile type sealing element are reserved.
Preferably, the inclined directions of the corresponding end surfaces of the upper brush seal and the lower brush seal are the same as the inclined directions of the brush tow at the position.
Further preferably, the tile-shaped magnets located on the outer periphery of the brush seal and the inner periphery of the stator are arranged in two rows on the left and right, and the two rows of tile-shaped magnets are symmetrical about the bolt.
Further preferably, the tile magnets are provided along the outer periphery of the brush seal and the inner periphery of the stator in 8 pairs, and 4 pairs are provided on each of the upper brush seal and the lower brush seal.
Further preferably, the tile-shaped magnet is adhered to the outer periphery of the brush seal and the inner periphery of the stator.
Further preferably, the bolts are welded to the fusion zones.
Further preferably, the gap between the upper brush seal and the lower brush seal is 1 to 2mm.
Further preferably, the brush seal comprises structurally identical 2 n A plurality of fan-shaped sub sealing units, wherein a bolt is fixed in the middle of the periphery of each sub sealing unit, and is screwed by a nut after passing through a through hole matched with the stator, wherein n>＝2。
The brush type sealing structure with the magnet capable of adjusting the radial gap between the brush filament bundles and the rotor surface has the advantages that:
1. simple structure, convenient to detach changes the maintenance, does not change traditional brush sealed basic structure, through increasing bolt and tile shape magnet, falls into two parts with brush sealing member simultaneously for brush silk bundle and rotor face's clearance is adjustable, specifically: when the nut is loosened, the brush type sealing element moves inwards under the action of the tile-shaped magnet, so that the radial gap between the brush filament bundles and the rotor surface can be reduced, when the nut is screwed down, the brush type sealing element moves outwards under the drive of the screw rod, so that the radial gap between the brush filament bundles and the rotor surface can be increased, the gap adjusting mode can avoid frequent replacement of the brush type sealing element, and the problem of reinstallation caused by overlarge or too close gap between the brush filament bundles and the rotor surface in the assembly process is also avoided;
2. when the rotor jumps, the bolts can move in the through holes, and the rotor drives the brush sealing piece to move radially while pushing the brush filament bundles, at the moment, the tile-shaped magnets distributed circumferentially provide inward uniform distribution force for the brush sealing piece, so that the brush filament bundles are tightly attached to the rotor surface, thereby effectively reducing the leakage flow, playing a good role in buffering and absorbing vibration, and ensuring the stable rotation of the rotor.
Drawings
The invention will be described in further detail with reference to the accompanying drawings and embodiments:
FIG. 1 is a schematic view of a brush seal structure with magnets for adjusting radial gap between brush filament bundles and a rotor surface;
FIG. 2 is an enlarged view of a portion of FIG. 1;
fig. 3 is a cross-sectional view A-A of fig. 1.
In the figure, 1-stator; 11-through holes; 21-a front baffle; 22-fusion welding zone; 23-a tailgate; 24-brushing the filament bundles; 3-tile-shaped magnets; 31-tile-shaped magnets fixed to the outer periphery of the brush seal; 32-tile-shaped magnets fixed to the inner periphery of the stator; 4-bolts; 5-rotor.
Detailed Description
The invention will be further explained below in connection with specific embodiments, but is not limited to the invention.
As shown in fig. 1 to 3, the present invention provides a brush seal structure comprising a magnet for adjusting a radial gap between a brush filament bundle and a rotor surface, comprising: the stator 1, brush seal and tile magnet 3, wherein, brush seal cooperates and sets up in the inner periphery of stator 1 and can be along the radial motion of rotor 5 in stator inboard, brush seal includes upper portion brush seal and lower brush seal that the clearance sets up and the structure is the same, upper portion brush seal and lower brush seal all include front bezel 21, fusion welding district 22, backplate 23 and brush silk bundle 24, front bezel 21 passes through fusion welding district 22 with backplate 23 to be connected, the root of brush silk bundle 24 is fixed on fusion welding district 22, the free end is laminated with rotor 5, the middle part of upper portion brush seal and lower portion brush seal's periphery is all fixed a bolt 4, pass through the through-hole 11 on stator 1 and screw through the nut of its cooperation back, through rotatory nut, upper portion brush seal and lower portion brush seal interval can be adjusted, the tile-shaped magnet 3 comprises a tile-shaped magnet 31 fixed on the periphery of the brush-type sealing element and a tile-shaped magnet 32 fixed on the inner periphery of the stator 1, the tile-shaped magnet 31 fixed on the periphery of the brush-type sealing element and the tile-shaped magnet 32 fixed on the inner periphery of the stator 1 are arranged in pairs and are respectively and uniformly distributed along the periphery of the brush-type sealing element and the inner periphery of the stator 1, each pair of tile-shaped magnets 3 repel each other, a gap is reserved, the gap can ensure that the radial runout of the rotor can not lead the inner periphery of the stator and the tile-shaped magnet on the periphery of the brush-type sealing element to contact each other, the brush-type sealing element can be driven to move outwards or inwards by screwing or loosening the nut, the radial gap between brush tows and the rotor surface can be indirectly adjusted, the gap between the brush-type sealing element and the brush-type sealing element is preferably 1-2 mm, the direction of inclination of the corresponding end faces of the upper and lower brush seals is preferably the same as the direction of inclination of the brush filaments 24 at that location.
The brush type sealing structure with the magnet capable of adjusting the radial gap between the brush filament bundle and the rotor surface does not change the basic structure of the traditional brush type sealing, and the brush type sealing element is divided into two parts by adding the bolt and the tile-shaped magnet, so that the gap between the brush filament bundle and the rotor surface is adjustable, and specifically: when the brush type sealing piece works for a period of time, the radial gap between the brush filament bundles and the rotor surface is enlarged, at the moment, the nut is loosened, the brush type sealing piece moves inwards under the action of the repulsive force of the tile-shaped magnet, so that the radial gap between the brush filament bundles and the rotor surface is reduced, the sealing performance of the brush type sealing structure is improved, the replacement cost is reduced, and good economic benefits are achieved; when the rotor jumps, the bolts can move in the through holes, and the rotor drives the brush sealing piece to move radially while pushing the brush filament bundles, at the moment, the tile-shaped magnets distributed circumferentially provide inward uniform distribution force for the brush sealing piece, so that the brush filament bundles are tightly attached to the rotor surface, thereby effectively reducing the leakage flow, playing a good role in buffering and absorbing vibration, and ensuring the stable rotation of the rotor.
As an improvement of the technical scheme, as shown in fig. 1 and 2, two rows of tile-shaped magnets 3 are arranged on the left and right sides of the outer periphery of the brush type sealing member and the inner periphery of the stator 1, and the two rows of tile-shaped magnets 3 are symmetrical about the bolt 4.
As an improvement of the technical scheme, the tile-shaped magnets 3 arranged along the outer periphery of the brush type sealing member and the inner periphery of the stator 1 are 8 pairs, and 4 pairs of the upper brush type sealing member and the lower brush type sealing member are arranged on each other.
As an improvement of the technical scheme, the tile-shaped magnet 3 is adhered to the outer periphery of the brush type sealing member and the inner periphery of the stator 1.
As an improvement, as shown in fig. 1 and 2, the bolt 4 is welded to the fusion zone 22.
Wherein, fig. 1 and 3 show schematic diagrams of brush seal structures in which brush seal elements are divided into two parts, and in order to better realize adjustment of radial clearance between brush filament bundles and rotor surfaces, the brush seal elements comprise 2 parts with the same structure as improvement of the technical proposal n A plurality of fan-shaped sub-sealing units, namely: the brush type sealing element is divided equally by n straight lines passing through the center of the brush type sealing element, a bolt 4 is fixed in the middle of the periphery of each sub-sealing unit, the bolt 4 passes through a through hole 11 matched with the stator 1 and is screwed by a nut, wherein n is as follows>＝2。
The embodiments of the present invention have been described in detail with reference to the drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the spirit of the present invention.
Claims (6)
1. Brush seal structure containing magnet adjustable brush filament bundle and rotor face radial gap, characterized by comprising: the brush type sealing element comprises a stator (1), brush type sealing elements and tile-shaped magnets (3), wherein the brush type sealing elements are matched with the inner periphery of the stator (1) and can move along the radial direction of the rotor (5) at the inner side of the stator, each brush type sealing element comprises an upper brush type sealing element and a lower brush type sealing element which are identical in structure, each brush type sealing element comprises a front baffle plate (21), a fusion welding area (22), a rear baffle plate (23) and brush filament bundles (24), the front baffle plates (21) are connected with the rear baffle plates (23) through the fusion welding areas (22), the root parts of the brush filament bundles (24) are fixed on the fusion welding areas (22), the free ends of the brush type sealing elements are respectively attached to the rotor (5), bolts (4) are fixed at the middle parts of the outer peripheries of the upper brush type sealing elements and the lower brush type sealing elements, the bolts (4) penetrate through holes (11) matched with the stator (1) and then can be adjusted through nuts, the gaps between the upper brush type sealing elements and the lower brush type sealing elements can be adjusted through rotating the nuts, the brush type sealing elements and the magnets (3) are fixed on the inner periphery of the stator (1) and the periphery of the stator (1) respectively, the magnet-shaped magnets (3) are fixed on the inner periphery of the stator and the inner periphery of the stator (1) respectively, the tile-shaped sealing element and the tile-shaped magnets (1) are fixed, the inclination directions of the corresponding end surfaces of the upper brush type sealing element and the lower brush type sealing element are the same as the inclination directions of brush filament bundles (24) at the positions, two rows of tile-shaped magnets (3) are arranged left and right and are symmetrical to the bolts (4) on the outer periphery of the brush type sealing element and the inner periphery of the stator (1).
2. The brush seal with adjustable brush tow to rotor face radial gap containing magnets of claim 1, wherein: the tile-shaped magnets (3) arranged along the outer periphery of the brush type sealing element and the inner periphery of the stator (1) are 8 pairs, and 4 pairs of the upper brush type sealing element and the lower brush type sealing element are respectively arranged on the upper brush type sealing element and the lower brush type sealing element.
3. The brush seal with adjustable brush tow to rotor face radial gap containing magnets of claim 1, wherein: the tile-shaped magnet (3) is adhered to the outer periphery of the brush type sealing piece and the inner periphery of the stator (1).
4. The brush seal with adjustable brush tow to rotor face radial gap containing magnets of claim 1, wherein: the bolts (4) are welded to the fusion zones (22).
5. The brush seal with adjustable brush tow to rotor face radial gap containing magnets of claim 1, wherein: the gap between the upper brush type sealing element and the lower brush type sealing element is 1-2 mm.
6. The brush seal with adjustable brush tow to rotor face radial gap containing magnets of claim 1, wherein: the brush type sealing member comprises 2 parts with the same structure n A plurality of fan-shaped sub sealing units, wherein a bolt (4) is fixed in the middle of the periphery of each sub sealing unit, the bolt (4) passes through a through hole (11) on the stator (1) matched with the stator and then is screwed by a nut, and n is as follows>=2。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910071749.8A CN109555564B (en) | 2019-01-25 | 2019-01-25 | Brush type sealing structure with magnet and adjustable radial gap between brush filament bundle and rotor surface |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910071749.8A CN109555564B (en) | 2019-01-25 | 2019-01-25 | Brush type sealing structure with magnet and adjustable radial gap between brush filament bundle and rotor surface |
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| Publication Number | Publication Date |
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| CN109555564A CN109555564A (en) | 2019-04-02 |
| CN109555564B true CN109555564B (en) | 2023-08-29 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201910071749.8A Active CN109555564B (en) | 2019-01-25 | 2019-01-25 | Brush type sealing structure with magnet and adjustable radial gap between brush filament bundle and rotor surface |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110043669B (en) * | 2019-04-04 | 2024-01-23 | 沈阳航空航天大学 | Two-stage brush type sealing structure capable of dynamically adjusting inter-stage unbalance |
| CN110017179B (en) * | 2019-04-18 | 2024-01-02 | 沈阳航空航天大学 | Brush type sealing structure with adjustable circumferential inclination angle of brush wire |
| CN113090339B (en) * | 2021-04-08 | 2022-08-02 | 沈阳航空航天大学 | Active clearance control brush type sealing structure based on magnetic attraction effect |
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| CN204041134U (en) * | 2014-07-02 | 2014-12-24 | 中国长江动力集团有限公司 | A kind of rotating barrier for 25MW adjustable extraction steam for factories steam turbine |
| CN105649685A (en) * | 2015-12-31 | 2016-06-08 | 沈阳航空航天大学 | Combined type brush sealing structure with radially adjustable brush wire bundle |
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2019
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| GB953931A (en) * | 1960-09-28 | 1964-04-02 | Licentia Gmbh | A multi-stage axial-flow elastic-fluid turbine |
| US3710418A (en) * | 1970-10-30 | 1973-01-16 | Wiesner Hager Kg | Chair having a back rest and means for adjusting the inclination thereof |
| EP0798578A1 (en) * | 1996-03-22 | 1997-10-01 | Corning Incorporated | Dispersion shifted optical waveguide fiber |
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| CN109555564A (en) | 2019-04-02 |
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