Sealing structure of axial flow compressor
By combining the double seal structure of maze seal and carbon ring seal in axial flow compressor, the problem that the traditional single maze sealing method cannot meet the modern market's seal leakage control requirements is solved, and efficient harmful media leakage reduction and zero leakage effects are achieved.
Patent Information
- Application Number
- CN202420134144.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-19
- Publication Date
- 2025-03-04
- Estimated Expiration
- 2034-01-19
AI Technical Summary
The single maze sealing method of traditional axial flow compressors cannot meet the new requirements of modern market for seal leakage control, especially when toxic and harmful gases exist, zero leakage cannot be achieved.
Using a dual seal structure combining labyrinth seal and carbon ring seal, a labyrinth seal gap and carbon ring seal gap are provided on the rotating shaft and sealing body, and a high-pressure sealing gas is provided with an inflatable hole to form a gas impedance to reduce medium leakage.
It effectively reduces the leakage of harmful media at the shaft end of the axial flow compressor, and even achieves zero leakage, improves the safety and reliability of the seal, and meets the strict requirements of modern market for seal leakage control.
Smart Images
Figure CN222558828U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a compressor sealing structure, in particular to a sealing structure of an axial flow compressor. Background Art
[0002] Axial flow compressor is a mechanical device that can continuously pressurize gas, mainly used in metallurgy, petrochemical and other fields. The working medium of traditional axial flow compressor is air, which is mainly formed by machining several sealing grooves on the main shaft and inlaying corresponding sealing teeth to cooperate with the sealing grooves on the sealing body to form a labyrinth seal with a gap, reduce gas leakage and achieve shaft end sealing.
[0003] The specific principle of labyrinth seal is as follows: a number of sealing grooves are processed on the air inlet and exhaust sides of the rotating shaft, and two different specifications of sealing sheets are inserted in the sealing grooves. The number of sealing sheets is calculated according to the amount of leakage. The inner holes of the air inlet and exhaust side sealing bodies installed on the casing are processed with high and low bosses respectively. The high and low bosses cooperate with the two specifications of sealing sheets to form a sealing gap. The sealing body is equipped with adjustment gaskets and adjustment blocks to adjust the size of the sealing gap. An expansion cavity is formed between two adjacent sealing sheets of different specifications. When the gas flows through the gap, the airflow is throttled, its pressure and temperature decrease, and the flow rate increases. An expansion cavity is formed between the two sealing sheets, and the volume of the gas in this cavity increases, the flow rate decreases, and a vortex flow is formed. As the number of gaps and cavities through which the gas flows increases and the gap value decreases, the flow rate and pressure drop of the gas become larger and larger. When the pressure drops to the back pressure, the gas is sealed.
[0004] At present, the commonly used structures for axial flow compressor seals are as follows: Figure 1 As shown, it includes a rotating shaft 01 for embedding an axial compressor sealing piece 02; a casing 03 is processed with bolt holes, and a sealing body 04 is connected to the casing by bolts during installation to fix the sealing body 04 and ensure its centering; the inner hole of the sealing body 04 is processed with high and low bosses to form a labyrinth seal with the sealing piece 02; an adjusting block 05 is used to adjust the sealing gap of the labyrinth seal.
[0005] However, with the development and progress of technology, the current market demand for axial flow compressors has changed. The working media are diverse, and many toxic and harmful gases are mixed in the working media. The leaked media may have a great impact on the environment near the unit and personal safety. The leakage must be strictly controlled, and sometimes even zero leakage is required. This change in market demand has put forward new requirements for the control of the sealing leakage of axial flow compressors, and the traditional single labyrinth sealing method cannot meet the market demand. Utility Model Content
[0006] The utility model aims to solve the technical problem that a single labyrinth seal method in the prior art cannot meet the requirement of seal leakage, and provides a seal structure for an axial flow compressor.
[0007] In order to solve the above technical problems, the technical solutions provided by the utility model are as follows:
[0008] A sealing structure of an axial compressor comprises an axial compressor housing provided with a through hole, a first sealing body is provided inside the axial compressor housing, and the first sealing body extends out of the through hole; a rotating shaft hole is provided on the first sealing body, and the rotating shaft of the axial compressor extends out of the rotating shaft hole;
[0009] Its special features are:
[0010] A labyrinth sealing gap is provided between the large end of the rotating shaft and the first sealing body;
[0011] The small end of the rotating shaft is sleeved with a sealing sleeve, and the outer side of the sealing sleeve is sleeved with a second sealing body, which is fixedly mounted on the outer end surface of the first sealing body, and the inner wall of the second sealing body is provided with a plurality of mounting grooves along the circumferential direction, and a carbon ring is mounted in the mounting groove;
[0012] The inner wall of the second sealing body, the outer wall of the sealing sleeve and the carbon ring form a carbon ring sealing gap.
[0013] Furthermore, a first air filling hole is provided on the second sealing body, and the first air filling hole connects the external air source with the carbon ring sealing gap;
[0014] The first sealing body is provided with an annular groove along the circumferential direction and a plurality of vent holes along the radial direction; the inlet of the vent hole is located in the annular groove, and the outlet is located in the labyrinth sealing gap;
[0015] A second air charging hole is provided on the housing of the axial flow compressor, a horizontal section of the second air charging hole is connected to an external air source, and a vertical section of the second air charging hole is connected to the annular groove;
[0016] The external gas source is used to provide sealing gas with a pressure higher than the leaking medium.
[0017] Furthermore, an adjustment block and a plurality of first gaskets are provided in the annular groove;
[0018] The adjusting block and a plurality of first gaskets are fixedly installed in the annular groove by screws.
[0019] Furthermore, a second gasket is provided between the second sealing body and the first sealing body.
[0020] Furthermore, a plurality of evenly distributed sealing grooves are formed at the large end of the rotating shaft along the axial direction; a sealing sheet is fixedly installed in the sealing groove;
[0021] A plurality of grooves corresponding to the sealing sheets are provided in the rotating shaft hole of the first sealing body; the plurality of grooves and the plurality of sealing sheets form a labyrinth sealing gap.
[0022] Furthermore, the sealing sheet is fixedly installed in the sealing groove via a pressure strip.
[0023] Furthermore, the first sealing body is connected to the axial flow compressor housing through a plurality of bolts.
[0024] Compared with the prior art, the utility model has the following beneficial effects:
[0025] 1. The sealing structure of the axial compressor provided by the utility model is provided with a sealing sleeve and a second sealing body on the basis of the prior art, and a plurality of carbon rings are installed on the inner wall of the second sealing body, so that the inner wall of the sealing body, the outer wall of the sealing sleeve and the carbon rings can form a carbon ring sealing gap. When the leaked harmful medium is not completely sealed by the labyrinth sealing gap, the leaked harmful medium forms a gas vortex when passing through the carbon ring to block the leakage of the harmful medium, thereby further sealing the shaft end of the axial compressor. By adopting the labyrinth sealing gap and the carbon ring sealing gap, the two sealing methods are combined to seal the shaft end of the axial compressor, so as to overcome the problem that the single labyrinth sealing method used in the prior art cannot meet the sealing leakage requirement.
[0026] 2. The sealing structure of the axial flow compressor provided by the utility model is provided with a second inflation hole on the axial flow compressor housing, and a first inflation hole on the sealing body. Sealing gas with a pressure higher than the leakage medium pressure can be respectively filled into the carbon ring sealing gap and the labyrinth sealing gap through the first inflation hole and the second inflation hole, so as to form gas impedance in the carbon ring sealing gap and the labyrinth sealing gap, so as to effectively reduce the leakage of the medium, or even achieve zero leakage, and ensure the personal safety of the staff. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 It is a structural schematic diagram of the prior art;
[0028] Attached Figure 1 Markings in the figure: 01-shaft, 02-sealing sheet, 03-housing, 04-sealing body, 05-adjusting block;
[0029] Figure 2 It is a structural schematic diagram of an embodiment of the sealing structure of an axial flow compressor of the utility model;
[0030] Figure 3 It is an enlarged schematic diagram of the structure of the second sealing body in the sealing structure embodiment of the axial flow compressor of the utility model;
[0031] Figure 4 It is an enlarged schematic diagram of the structure of the sealing sheet in the sealing structure embodiment of the axial flow compressor of the utility model.
[0032] Attached Figure 2-4Marking description: 1-rotating shaft, 2-sealing plate, 3-sealing sleeve, 4-axial flow compressor housing, 5-first sealing body, 6-second sealing body, 61-mounting groove, 62-carbon ring, 7-first gasket, 8-adjusting block, 9-second gasket, 10-pressing strip, 11-first inflation hole, 12-second inflation hole, 13-bolt, 14-annular groove, 141-vent hole. DETAILED DESCRIPTION
[0033] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0034] like Figure 2 As shown, a sealing structure of an axial compressor includes an axial compressor housing 4 provided with a through hole, a first sealing body 5 is provided on the inner side of the axial compressor housing 4, a plurality of threaded holes are provided on the axial compressor housing 4, the first sealing body 5 is connected to the axial compressor housing 4 through a plurality of bolts 13, and the first sealing body 5 extends out from the through hole; a shaft hole is provided on the first sealing body 5, and the axial compressor shaft 1 extends out from the shaft hole.
[0035] In order to effectively reduce the leakage of harmful media from the shaft end of the axial flow compressor during operation, ensure the safe operation of the unit, and ensure the personal safety of the staff; a combination of labyrinth seal and carbon ring seal is adopted to improve the shaft end seal of the axial flow compressor.
[0036] The labyrinth seal is:
[0037] like Figure 2 and Figure 4 As shown, a plurality of evenly distributed sealing grooves are provided at the large end of the rotating shaft 1 along the axial direction; the sealing sheet 2 is fixedly installed in the sealing groove by means of a pressure strip 10; a plurality of grooves corresponding to the sealing sheets 2 are provided in the rotating shaft hole of the first sealing body 5; and the plurality of grooves and the plurality of sealing sheets 2 form a labyrinth sealing gap.
[0038] When the harmful medium passes through the labyrinth sealing gap composed of multiple sealing sheets 2 and multiple grooves, the flow rate and pressure of the harmful medium are continuously reduced. When the pressure of the harmful medium drops to the back pressure, the sealing of the shaft end of the axial flow compressor is achieved.
[0039] Carbon ring seals are:
[0040] like Figure 2 and Figure 3As shown, a sealing sleeve 3 is sleeved on the small end of the rotating shaft 1, and a second sealing body 6 is sleeved on the outside of the sealing sleeve 3. The second sealing body 6 is fixedly installed on the outer end surface of the first sealing body 5. A plurality of mounting grooves 61 are opened on the inner wall of the second sealing body 6 along the circumferential direction, and a carbon ring 62 is installed in the mounting groove 61; the inner wall of the second sealing body 6, the outer wall of the sealing sleeve 3 and the carbon ring 62 form a carbon ring sealing gap.
[0041] When the leaked harmful medium passes through the isolation groove, a gas vortex is formed to isolate the leakage of the harmful medium, thereby achieving further sealing of the shaft end of the axial flow compressor.
[0042] In order to effectively reduce the leakage of harmful media at the shaft end of the axial compressor, or even achieve zero leakage, such as Figure 2 As shown, a first air filling hole 11 is provided on the second sealing body 6, and the first air filling hole 11 connects the external gas source with the carbon ring sealing gap; a circular groove 14 is provided on the first sealing body 5 along the circumferential direction, and a plurality of radial vents 141; the inlet of the vent 141 is located in the circular groove 14, and the outlet is located in the labyrinth sealing gap; a second air filling hole 12 is provided on the axial flow compressor housing 4, and the horizontal section of the second air filling hole 12 is connected to the external gas source, and the vertical section of the second air filling hole 12 is connected to the circular groove 14; the external gas source is used to provide sealing gas with a pressure higher than the leakage medium. After the sealing gas enters the carbon ring sealing gap from the first air filling hole 11, an air film is formed between the first sealing body 6 and the sealing sleeve 3, generating throttling and pressure reduction, and preventing the high-pressure side gas from flowing to the low-pressure side; the sealing gas enters the labyrinth sealing gap from the second air filling hole 12, the circular groove 14 and the vent 141 to form a gas impedance.
[0043] In order to facilitate the adjustment of the size of the labyrinth seal gap, such as Figure 2 As shown, an adjustment block 8 and a plurality of first gaskets 7 are provided in the annular groove 14 ; the adjustment block 8 and the plurality of first gaskets 7 are fixedly installed in the annular groove 14 by screws.
[0044] In order to adjust the axial installation position of the second sealing body 6 on the sealing body 5, as shown in FIG. Figure 2 As shown, a second gasket 9 is provided between the second sealing body 6 and the first sealing body 5 , and the axial installation position of the second sealing body 6 on the first sealing body 5 can be adjusted by increasing or decreasing the thickness of the second gasket 9 .
[0045] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any changes or replacements within the technical scope disclosed in the utility model should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.
Claims
1. A sealing structure of an axial compressor, comprising an axial compressor housing (4) provided with a through hole, a first sealing body (5) provided inside the axial compressor housing (4), and the first sealing body (5) extending out of the through hole; The first sealing body (5) is provided with a rotating shaft hole, and the rotating shaft (1) of the axial flow compressor extends out of the rotating shaft hole; Features: A labyrinth seal gap is provided between the large end of the rotating shaft (1) and the first sealing body (5); A sealing sleeve (3) is sleeved on the small end of the rotating shaft (1), a second sealing body (6) is sleeved on the outside of the sealing sleeve (3), the second sealing body (6) is fixedly mounted on the outer end surface of the first sealing body (5), a plurality of mounting grooves (61) are formed on the inner wall of the second sealing body (6) along the circumferential direction, and a carbon ring (62) is mounted in the mounting groove (61); The inner wall of the second sealing body (6), the outer wall of the sealing sleeve (3) and the carbon ring (62) form a carbon ring sealing gap.
2. The sealing structure of the axial flow compressor according to claim 1, characterized in that: The second sealing body (6) is provided with a first air filling hole (11), and the first air filling hole (11) connects an external air source with the carbon ring sealing gap; The first sealing body (5) is provided with a circumferential annular groove (14) and a plurality of radial vent holes (141); the inlet of the vent hole (141) is located in the annular groove (14), and the outlet is located in the labyrinth seal gap; The axial compressor housing (4) is provided with a second air filling hole (12), the horizontal section of the second air filling hole (12) is connected to an external air source, and the vertical section of the second air filling hole (12) is connected to the annular groove (14); The external gas source is used to provide sealing gas with a pressure higher than the leaking medium.
3. The sealing structure of the axial flow compressor according to claim 2, characterized in that: An adjustment block (8) and a plurality of first gaskets (7) are arranged in the annular groove (14); The adjustment block (8) and a plurality of first gaskets (7) are fixedly installed in the annular groove (14) by means of screws.
4. The sealing structure of the axial flow compressor according to claim 1, characterized in that: A second gasket (9) is provided between the second sealing body (6) and the first sealing body (5).
5. The sealing structure of the axial flow compressor according to claim 1, characterized in that: The large end of the rotating shaft (1) is provided with a plurality of evenly distributed sealing grooves along the axial direction; a sealing sheet (2) is fixedly installed in the sealing groove; A plurality of grooves corresponding to the sealing sheets (2) are provided in the rotating shaft hole of the first sealing body (5); the plurality of grooves and the plurality of sealing sheets (2) form a labyrinth sealing gap.
6. The sealing structure of the axial flow compressor according to claim 5, characterized in that: The sealing sheet (2) is fixedly installed in the sealing groove via a pressure strip (10).
7. The sealing structure of the axial flow compressor according to claim 1, characterized in that: The first sealing body (5) is connected to the axial flow compressor housing (4) via a plurality of bolts (13).