CN113738706B - Anti-surge muffler device for vacuum pump system - Google Patents
Anti-surge muffler device for vacuum pump system Download PDFInfo
- Publication number
- CN113738706B CN113738706B CN202111103105.6A CN202111103105A CN113738706B CN 113738706 B CN113738706 B CN 113738706B CN 202111103105 A CN202111103105 A CN 202111103105A CN 113738706 B CN113738706 B CN 113738706B
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- Prior art keywords
- stage throttling
- baffle
- stage
- surge
- vacuum pump
- Prior art date
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- 230000030279 gene silencing Effects 0.000 claims abstract description 19
- 238000010521 absorption reaction Methods 0.000 claims description 18
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 230000008030 elimination Effects 0.000 claims description 6
- 238000003379 elimination reaction Methods 0.000 claims description 6
- 239000000463 material Substances 0.000 claims description 5
- 229910000838 Al alloy Inorganic materials 0.000 claims description 3
- 229920005830 Polyurethane Foam Polymers 0.000 claims description 3
- 239000011491 glass wool Substances 0.000 claims description 3
- 229920003023 plastic Polymers 0.000 claims description 3
- 239000004033 plastic Substances 0.000 claims description 3
- 239000011496 polyurethane foam Substances 0.000 claims description 3
- 230000008859 change Effects 0.000 abstract description 5
- 230000009286 beneficial effect Effects 0.000 abstract description 4
- 230000009467 reduction Effects 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 2
- 239000010410 layer Substances 0.000 description 11
- 239000011241 protective layer Substances 0.000 description 4
- 230000006978 adaptation Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
- F04D29/663—Sound attenuation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
- F04D29/667—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps by influencing the flow pattern, e.g. suppression of turbulence
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Pipe Accessories (AREA)
Abstract
The invention discloses an anti-surge muffler device for a vacuum pump system, which comprises a connecting flange and an elbow, wherein one end of the elbow is communicated with an anti-surge valve arranged on the vacuum pump system, the other end of the elbow is provided with an air inlet muffler component, the air inlet muffler component comprises a first-stage throttling baffle and a second-stage throttling baffle which are sequentially arranged along the air inlet direction, a first-stage throttling depressurization section is formed between the first-stage throttling baffle and the second-stage throttling baffle, a second-stage throttling depressurization section is formed between the second-stage throttling baffle and the elbow, and gas sequentially passes through the first-stage throttling baffle, the first-stage throttling depressurization section, the second-stage throttling baffle and the second-stage throttling depressurization section and enters the anti-surge valve after being decelerated and muffled; the invention is based on the two-stage throttling depressurization and resistive silencing principle, effectively reduces turbulent noise of high-pressure and high-flow-rate air flow, has wide noise reduction frequency band and strong adaptability, has good noise reduction effect on low, medium and high frequency band noise, and is beneficial to balancing pressure change in a vacuum pump system and avoiding severe surge damage of an impeller due to a throttling convergent and divergent structure.
Description
Technical Field
The invention relates to the technical field of noise reduction and noise elimination, in particular to an anti-surge noise elimination device for a vacuum pump system.
Background
In the operation process of the vacuum pump system, when the vacuum degree is too high, the anti-surge valve arranged on the steam-water separator is opened, so that gas enters the vacuum system to avoid surge. Because the high-speed gas entering instantly has larger airflow noise, the high air pressure released by the anti-surge valve is prevented from influencing the air pressure field in the volute, and the air pressure in the vacuum pump system is effectively balanced. And the high-speed airflow noise of instantaneous air intake is effectively eliminated.
The existing anti-surge valve is lack of a muffler device, when the anti-surge valve is opened, larger airflow noise is generated, and the impeller is impacted due to the rapid change of internal and external pressure, so that the impeller is easily damaged.
Disclosure of Invention
The technical purpose is that: aiming at the defects that the existing vacuum pump surge valve is large in opening noise and gas impacts an impeller, the invention discloses an anti-surge silencing device of a vacuum pump system, which is used for silencing air inlet of the surge valve and balancing pressure change in the vacuum pump system.
The technical scheme is as follows: in order to achieve the technical purpose, the invention adopts the following technical scheme:
the utility model provides a vacuum pump system's anti-surge silencing device, including flange and return bend, return bend one end and the anti-surge valve intercommunication of setting on vacuum pump system, the other end sets up the noise elimination subassembly that admits air, the noise elimination subassembly that admits air includes to set gradually one-level throttle baffle, second grade throttle baffle along the direction of admitting air, form one-level throttle depressurization section between one-level throttle baffle and second grade throttle baffle, form second grade throttle depressurization section between second grade throttle baffle and return bend, gaseous through one-level throttle baffle, one-level throttle depressurization section, second grade throttle baffle, second grade throttle depressurization section in proper order, get into anti-surge valve after the noise elimination of slowing down.
Preferably, the first-stage throttling baffle and the second-stage throttling baffle of the invention are both in tubular structures, the tubular body formed by the second-stage throttling baffle is concentrically positioned in the tubular body formed by the first-stage throttling baffle, the first-stage throttling depressurization section is positioned between the inner wall of the first-stage throttling baffle and the outer wall of the second-stage throttling baffle, the bent pipe is provided with a fixed plate for fixing the first-stage throttling baffle and the second-stage throttling baffle at one end close to the air intake silencing assembly, the center of the fixed plate is provided with an opening for communicating the second-stage throttling baffle and the bent pipe, the part of the fixed plate, which coincides with the first-stage throttling depressurization section, adopts a closed structure, gas flows into the second-stage throttling baffle from the first-stage throttling depressurization section, and flows into the bent pipe from the opening in the center of the fixed plate.
Preferably, the primary throttling baffle and the secondary throttling baffle of the invention adopt perforation structures, the perforation aperture of the primary throttling baffle is 5 mm-20 mm, and the perforation rate is 5% -20%.
Preferably, the aperture of the secondary throttling baffle perforation is 1 mm-15 mm, and the perforation rate is 1% -15%.
Preferably, the inner wall of the elbow pipe is sequentially provided with the perforation protective layer and the sound absorption layer from inside to outside, and the perforation protective layer compresses the sound absorption layer on the inner wall of the elbow pipe.
Preferably, the perforated facing layer of the invention comprises aluminum alloy and galvanized plate, the perforation ratio is 5% -40%, the aperture is 0.1 mm-15 mm, the aperture spacing is 1 mm-20 mm, and the thickness of the perforated facing layer is 0.5 mm-5 mm.
Preferably, the sound absorption layer of the invention adopts porous sound absorption material, and comprises superfine glass wool and polyurethane foam plastic, the thickness of the sound absorption layer is 20 mm-150 mm, and the volume weight is 20kg/m 3 ~50kg/m 3 The water content is 0.2-3%, the mass moisture absorption rate is 2-8%, and the water repellency rate is more than or equal to 98%.
The beneficial effects are that: the anti-surge muffler device for the vacuum pump system has the following beneficial effects:
1. the invention is based on the two-stage throttling depressurization and resistive silencing principles, effectively reduces turbulent noise of high-pressure and high-flow-rate air flow, reduces noise bandwidth, has strong adaptability, and solves the problem of huge noise when the anti-surge valve of the vacuum pump is opened.
2. The invention has good noise reduction effect on noise in low, medium and high frequency bands through the design of the perforation structure.
3. The invention is beneficial to balancing the pressure change in the vacuum pump system through the throttling convergent-divergent structure of the two-stage throttling depressurization section, reduces the impact of air intake on the impeller, and avoids the severe surge damage of the impeller.
4. The invention has the advantages of simple structure, small volume and convenient installation.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below.
FIG. 1 is a perspective view of the present invention;
FIG. 2 is an internal structural diagram of the present invention;
wherein, 1-flange, 2-return bend, 3-one-level throttle baffle, 4-second grade throttle baffle, 5-one-level throttle depressurization section, 6-second grade throttle depressurization section, 7-fixed plate.
Detailed Description
The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown, but in which the invention is not so limited.
The invention discloses an anti-surge silencing device for a vacuum pump system, which is shown in fig. 1 and 2, and comprises a connecting flange 1 and a bent pipe 2, wherein one end of the bent pipe 2 is communicated with an anti-surge valve arranged on the vacuum pump system, the other end of the bent pipe is provided with an air inlet silencing assembly, the air inlet silencing assembly comprises a first-stage throttling baffle 3 and a second-stage throttling baffle 4 which are sequentially arranged along the air inlet direction, a first-stage throttling depressurization section 5 is formed between the first-stage throttling baffle 3 and the second-stage throttling baffle 4, a second-stage throttling depressurization section 6 is formed between the second-stage throttling baffle 4 and the bent pipe 2, and gas sequentially passes through the first-stage throttling baffle 3, the first-stage throttling depressurization section 5, the second-stage throttling baffle 4 and the second-stage throttling depressurization section 6 and enters the anti-surge valve after being subjected to deceleration silencing.
According to the invention, the primary throttle baffle 3 and the secondary throttle baffle 4 are both in tubular structures, the tubular body formed by the secondary throttle baffle 4 is concentrically positioned in the tubular body formed by the primary throttle baffle 3, the primary throttle depressurization section 5 is positioned between the inner wall of the primary throttle baffle 3 and the outer wall of the secondary throttle baffle 4, the fixed plate 7 used for fixing the primary throttle baffle 3 and the secondary throttle baffle 4 is arranged at one end of the elbow 2 close to the air intake silencing assembly, the center of the fixed plate 7 is provided with an opening used for communicating the secondary throttle baffle 4 and the elbow, the overlapping part of the fixed plate 7 and the primary throttle depressurization section 5 adopts a closed structure, gas flows into the secondary throttle baffle 4 from the opening in the center of the fixed plate 7, high-speed airflow after being subjected to secondary throttle depressurization flows into the elbow 2 through the elbow, the primary throttle baffle 3 and the secondary throttle baffle 4 mainly reduce the air intake speed except for silencing, and avoid causing severe impact on impellers and impeller damage.
According to the invention, the primary throttling baffle 3 and the secondary throttling baffle 4 are both in a perforation structure, so that the pressure of the discharged air can be effectively reduced by perforation, and the perforation aperture of the primary throttling baffle 3 for eliminating high-speed airflow noise is 5 mm-20 mm, preferably 8mm; the penetration rate is 5% -20%, preferably 10%; the aperture of the secondary throttle baffle 4 is 1 mm-15 mm, preferably 5mm; the penetration rate is 1% -15%, preferably 5%.
The invention sequentially sets a perforation protective layer and a sound absorption layer from inside to outside on the inner wall of the elbow pipe 2, and the perforation protective layer is used for absorbing the sound absorption layerThe material adopted by the perforation protection layer comprises aluminum alloy and galvanized sheet, and the perforation ratio is 5% -40%, preferably 15%; the aperture is 0.1 mm-15 mm, preferably 1.5mm; the hole spacing is 1 mm-20 mm, preferably 3mm; the thickness of the perforation protection layer is 0.5 mm-5 mm, preferably 1.5mm; the sound absorption layer is made of porous sound absorption materials, and comprises superfine glass wool and polyurethane foam plastic, and the thickness of the sound absorption layer is 20 mm-150 mm, preferably 50mm; weight per unit 20kg/m 3 ~50kg/m 3 Preferably 36kg/m 3 The method comprises the steps of carrying out a first treatment on the surface of the The water content is 0.2% -3%, preferably 0.5%; the mass moisture absorption rate is 2% -8%, preferably 2.5%; the hydrophobic rate is more than or equal to 98%, the flow resistance is proper, the pores are uniform, and the sound absorption performance and the chemical stability are high.
When the anti-surge silencing device for the vacuum pump system is used, the silencing device is communicated with the air inlet end of the anti-surge valve through the connecting flange, when the vacuum degree is overlarge, the anti-surge valve arranged on the steam-water separator of the vacuum pump system is opened, air in the environment enters from the first-stage throttling baffle 3, high-pressure air flows pass through the first-stage throttling depressurization section 5, the high-pressure air flows enter the second-stage throttling baffle 4 after being subjected to primary depressurization, air flows through the second-stage throttling baffle 4 enter the second-stage throttling depressurization section 6, the high-speed air flows after being subjected to secondary throttling depressurization enter the bent pipe from the opening in the center of the fixing plate 7, and enter the vacuum pump system after being subjected to secondary silencing through the resistive silencing section of the bent pipe; the gradually-reduced structure from the first-stage throttling and depressurization section 5 to the second-stage throttling and depressurization section 6 formed by the air inlet silencing assembly and the gradually-reduced structure from the second-stage throttling and depressurization section 6 to the bent pipe 2 solve the problems of reducing the air flow rate and balancing the pressure change in the shell of the vacuum pump while air inlet silencing, and can prevent the impeller from being damaged while preventing surge.
The foregoing is only a preferred embodiment of the invention, it being noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the present invention, and such modifications and adaptations are intended to be comprehended within the scope of the invention.
Claims (5)
1. The anti-surge muffler device for the vacuum pump system is characterized by comprising a connecting flange (1) and an elbow (2), wherein one end of the elbow (2) is communicated with an anti-surge valve arranged on the vacuum pump system, the other end of the elbow is provided with an air inlet muffler component, the air inlet muffler component comprises a first-stage throttling baffle (3) and a second-stage throttling baffle (4) which are sequentially arranged along the air inlet direction, a first-stage throttling depressurization section (5) is formed between the first-stage throttling baffle (3) and the second-stage throttling baffle (4), a second-stage throttling depressurization section (6) is formed between the second-stage throttling baffle (4) and the elbow (2), and gas sequentially passes through the first-stage throttling baffle (3), the first-stage throttling depressurization section (5), the second-stage throttling baffle (4) and the second-stage throttling depressurization section (6) and enters the anti-surge valve after being subjected to deceleration and noise elimination;
the one-stage throttling baffle (3) and the two-stage throttling baffle (4) are of tubular structures, tubular bodies formed by the two-stage throttling baffle (4) are concentrically located in tubular bodies formed by the one-stage throttling baffle (3), a one-stage throttling depressurization section (5) is located between the inner wall of the one-stage throttling baffle (3) and the outer wall of the two-stage throttling baffle (4), a fixed plate (7) for fixing the one-stage throttling baffle (3) and the two-stage throttling baffle (4) is arranged at one end, close to an air inlet silencing assembly, of the bent pipe (2), an opening for communicating the two-stage throttling baffle (4) with the bent pipe is formed in the center of the fixed plate (7), a closed structure is adopted at the overlapping part of the fixed plate (7) and the one-stage throttling depressurization section (5), air flows into the two-stage throttling baffle (4) from the one-stage throttling depressurization section (5), and flows into the bent pipe (2) from the opening in the center of the fixed plate (7);
the primary throttling baffle (3) and the secondary throttling baffle (4) are of perforation structures, the perforation aperture of the primary throttling baffle (3) is 5 mm-20 mm, and the perforation rate is 5% -20%.
2. The anti-surge muffler device for a vacuum pump system according to claim 1, wherein the aperture of the secondary throttle baffle (4) is 1 mm-15 mm, and the aperture ratio is 1% -15%.
3. The anti-surge muffler device for a vacuum pump system according to claim 1, wherein the inner wall of the elbow (2) is provided with a perforated protecting layer and a sound absorbing layer in sequence from inside to outside, and the perforated protecting layer compresses the sound absorbing layer on the inner wall of the elbow.
4. The anti-surge muffler device for a vacuum pump system according to claim 3, wherein the perforated facing layer is made of aluminum alloy or galvanized plate, the perforation rate is 5% -40%, the aperture is 0.1 mm-15 mm, the aperture distance is 1 mm-20 mm, and the thickness of the perforated facing layer is 0.5 mm-5 mm.
5. The anti-surge muffler device for a vacuum pump system according to claim 3, wherein the sound absorption layer is made of porous sound absorption material, the porous sound absorption material is superfine glass wool or polyurethane foam plastic, the thickness of the sound absorption layer is 20 mm-150 mm, and the volume weight is 20kg/m 3 ~50kg/m 3 The water content is 0.2-3%, the mass moisture absorption rate is 2-8%, and the water repellency rate is more than or equal to 98%.
Priority Applications (1)
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CN202111103105.6A CN113738706B (en) | 2021-09-18 | 2021-09-18 | Anti-surge muffler device for vacuum pump system |
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CN202111103105.6A CN113738706B (en) | 2021-09-18 | 2021-09-18 | Anti-surge muffler device for vacuum pump system |
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CN113738706A CN113738706A (en) | 2021-12-03 |
CN113738706B true CN113738706B (en) | 2024-02-13 |
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CN202111103105.6A Active CN113738706B (en) | 2021-09-18 | 2021-09-18 | Anti-surge muffler device for vacuum pump system |
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Citations (8)
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US4979587A (en) * | 1989-08-01 | 1990-12-25 | The Boeing Company | Jet engine noise suppressor |
CN201179406Y (en) * | 2008-04-15 | 2009-01-14 | 苏州苏净保护气氛有限公司 | Air discharge emptying silencer muffler |
CN203114751U (en) * | 2013-02-01 | 2013-08-07 | 中国航空工业集团公司西安飞机设计研究所 | Integrated noise reduction device for vacuum pump |
CN203311840U (en) * | 2013-05-06 | 2013-11-27 | 杭州鼎岳空分设备有限公司 | Straight-line silencer for air separation device exhaust system |
CN108561289A (en) * | 2018-03-06 | 2018-09-21 | 安徽朝祯环保科技有限公司 | A kind of exhaust silencer |
CN111255975A (en) * | 2020-02-24 | 2020-06-09 | 马鞍山钢铁股份有限公司 | Blast furnace blower air-releasing pipe silencing and vibration damping device, manufacturing method and blast furnace blower system |
CN211648607U (en) * | 2020-01-02 | 2020-10-09 | 振欣透平机械有限公司 | Subassembly is prevented breathing heavily by turbine vacuum pump bypass |
CN212225615U (en) * | 2020-06-02 | 2020-12-25 | 亿昇(天津)科技有限公司 | Magnetic suspension vacuum pump anti-surge valve muffler |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
BR112012019250A2 (en) * | 2010-02-02 | 2019-09-24 | Du Pont | integrated silencer with a catalytic converter |
CN109386505B (en) * | 2017-08-09 | 2022-02-11 | 开利公司 | Silencer for refrigerating device and refrigerating device |
-
2021
- 2021-09-18 CN CN202111103105.6A patent/CN113738706B/en active Active
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4979587A (en) * | 1989-08-01 | 1990-12-25 | The Boeing Company | Jet engine noise suppressor |
CN201179406Y (en) * | 2008-04-15 | 2009-01-14 | 苏州苏净保护气氛有限公司 | Air discharge emptying silencer muffler |
CN203114751U (en) * | 2013-02-01 | 2013-08-07 | 中国航空工业集团公司西安飞机设计研究所 | Integrated noise reduction device for vacuum pump |
CN203311840U (en) * | 2013-05-06 | 2013-11-27 | 杭州鼎岳空分设备有限公司 | Straight-line silencer for air separation device exhaust system |
CN108561289A (en) * | 2018-03-06 | 2018-09-21 | 安徽朝祯环保科技有限公司 | A kind of exhaust silencer |
CN211648607U (en) * | 2020-01-02 | 2020-10-09 | 振欣透平机械有限公司 | Subassembly is prevented breathing heavily by turbine vacuum pump bypass |
CN111255975A (en) * | 2020-02-24 | 2020-06-09 | 马鞍山钢铁股份有限公司 | Blast furnace blower air-releasing pipe silencing and vibration damping device, manufacturing method and blast furnace blower system |
CN212225615U (en) * | 2020-06-02 | 2020-12-25 | 亿昇(天津)科技有限公司 | Magnetic suspension vacuum pump anti-surge valve muffler |
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CN113738706A (en) | 2021-12-03 |
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