EP0165145A1 - In situ regenerierbarer Geräuschdämpfer für Ventilator in, mit staubhaltiger Luft geförderten Ventilationsanlagen und in situ Regenerierungsprozess dafür - Google Patents

In situ regenerierbarer Geräuschdämpfer für Ventilator in, mit staubhaltiger Luft geförderten Ventilationsanlagen und in situ Regenerierungsprozess dafür Download PDF

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Publication number
EP0165145A1
EP0165145A1 EP85400978A EP85400978A EP0165145A1 EP 0165145 A1 EP0165145 A1 EP 0165145A1 EP 85400978 A EP85400978 A EP 85400978A EP 85400978 A EP85400978 A EP 85400978A EP 0165145 A1 EP0165145 A1 EP 0165145A1
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EP
European Patent Office
Prior art keywords
layer
silencer
compressed air
situ
sound
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP85400978A
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English (en)
French (fr)
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EP0165145B1 (de
Inventor
Pierre Collod
Jean Louis 7 Rue Du Chemin De Fer Pawlak
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Charbonnages de France CDF
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Charbonnages de France CDF
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Publication date
Application filed by Charbonnages de France CDF filed Critical Charbonnages de France CDF
Priority to AT85400978T priority Critical patent/ATE36585T1/de
Publication of EP0165145A1 publication Critical patent/EP0165145A1/de
Application granted granted Critical
Publication of EP0165145B1 publication Critical patent/EP0165145B1/de
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M35/00—Combustion-air cleaners, air intakes, intake silencers, or induction systems specially adapted for, or arranged on, internal-combustion engines
    • F02M35/12—Intake silencers ; Sound modulation, transmission or amplification
    • F02M35/1272—Intake silencers ; Sound modulation, transmission or amplification using absorbing, damping, insulating or reflecting materials, e.g. porous foams, fibres, rubbers, fabrics, coatings or membranes
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
    • E21F1/00—Ventilation of mines or tunnels; Distribution of ventilating currents
    • E21F1/08—Ventilation arrangements in connection with air ducts, e.g. arrangements for mounting ventilators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M35/00—Combustion-air cleaners, air intakes, intake silencers, or induction systems specially adapted for, or arranged on, internal-combustion engines
    • F02M35/12—Intake silencers ; Sound modulation, transmission or amplification
    • F02M35/1283—Manufacturing or assembly; Connectors; Fixations
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/24—Means for preventing or suppressing noise

Definitions

  • the invention relates to sound attenuation silencers which are associated with fans supplied with dusty air; It also relates to a process for regenerating these silencers.
  • These silencers are generally cylindrical devices comprising an outer sheet metal wall against LaqueLLe is maintained an annular layer of a material with high sound-absorbing power, resistant to heat, humidity and compaction.
  • the sound absorbing substance used can be Rock wool, Glass wool, open cell foam, clay foam, etc.
  • the internal wall of the silencer in contact with the air flow to be soundproofed consists of a perforated sheet, The internal face of this sheet now in place The layer of soundproofing substance.
  • a central anaLogue bulb with a domed head generally cylindrical or frustoconical. This bulb ensures better continuity of air flow and promotes the supply of the fan wheel. This bulb also contains a sound absorbing material held in place by a perforated sheet envelope. It also participates in noise attenuation.
  • the main object of the invention is to achieve in situ regenerable silencers, if desired while the fans are running, which can be regenerated easily as often as the need arises to keep the noise nuisance below of a fixed threshold.
  • an in situ regenerable silencer intended to be associated with a fan in a ventilation installation supplied with dusty air, comprising an outer casing made of solid sheet metal, a layer of soundproofing material supported by a perforated internal wall , the outer casing made of solid sheet and the layer of sound-absorbing material are separated from each other and there exists on the outer face of this layer of insulating material a retaining wall with large passage openings separate from the envelope outside.
  • the outer casing in solid sheet metal comprises removable panels, preferably opening panels mounted using hinges relative to the fixed remainder of said outer envelope.
  • a gap revealing an annular volume which is connected to a connection end piece of a supply line for a cleaning fluid.
  • the perforated internal wall which supports the soundproofing material comprises a cage constituted by perforated tubes and connected to a means of connection to a network of pressurized air.
  • the cleaning fluid is preferably constituted by water added with a detergent.
  • the regeneration of the layer of the sound absorbing material of the silencer is done in the following way.
  • the annular volume comprised between the outer envelope of the silencer and the layer of sound-absorbing material is injected simultaneously with compressed air and cleaning fluid without stopping the fan.
  • the cleaning fluid mist passes through the layer of sound-absorbing material and carries the dust into the air flow sucked in or blown out by the fan. Then one can either stop the introduction of cleaning fluid alone and then continue the introduction of air so as to dry the layer of sound-absorbing material, or simultaneously stop the introduction of cleaning fluid and compressed air.
  • the wet dust obtained during regeneration is not a nuisance.
  • the cleaning fluid is preferably prepared beforehand in a bottle of adequate capacity and resistance to pressure connected on the one hand to the annular volume situated between the outer casing and the layer of sound-absorbing material and on the other hand to a source of compressed air, a cut-off valve being mounted between the cylinder and the compressed air source.
  • the opening of the valve causes spraying of the cleaning fluid in the form of a mist on the layer of sound-absorbing material.
  • iL is preferable but not necessarily necessary to stop the fan before cleaning the layer of sound-absorbing material.
  • a removable panel is moved and a pressurized water jet is sprayed onto the soundproofing material with the addition of a detergent. This is done panel by panel.
  • the internal face of the layer of sound-absorbing material is supported by a rot-proof fabric made of artificial fibers (polyamide, polyethylene) or non-combustible (fibers glass) with loose texture presenting more than 50% of empty surface.
  • This fabric has the advantage of not catching dust which facilitates its regeneration.
  • this fabric has a higher acoustic efficiency than a perforated sheet.
  • This fabric is itself supported by a sufficiently rigid mesh but with very loose mesh, for example in galvanized or plasticized wire. It can also rest on a metal cage.
  • This cage is formed of widely spaced metal bars oriented along the axis of the silencer. It has the advantage of protecting against the appearance of dangerous static electricity charges.
  • This metal cage is preferably constituted by tubes capable of being connected to a source of compressed air by means of a flexible hose and an electropneumatic valve; they are arranged so that, after connection, they play the role of ejectors, the jets of which are directed towards the blades of the fan. In addition to rapid drying of the sound-absorbing material after washing, this assembly allows useful automatic emergency ventilation in the event of accidental interruption of the electric current or not.
  • the external retaining wall of the layer of sound-absorbing material may consist of a metal cage or a sufficiently rigid mesh with loose mesh or holding in place a fabric with a loose texture.
  • the layer of sound-absorbing material can be constituted in a known manner by rock wool, glass wool or any other porous material.
  • annular volume between the external sheet of the silencer and the layer of soundproofing material may be divided by partitions so as to form several boxes.
  • These boxes can be connected successively to the compressed air source. These boxes can be longitudinal or transverse.
  • the silencers When the silencers are provided with a central bulb, constituted by a sound-absorbing material held in place by an envelope, there is provided inside this layer of sound-absorbing material a central volume bounded by an internal wall and connected to a connection end piece. a cleaning fluid inlet pipe.
  • the regeneration of the bulb takes place in the same way as that of the annular layer of sound-absorbing material.
  • the regeneration of the bulb and the annular layer can be carried out simultaneously or independently.
  • the external wall of the bulb is as in the case of the external cylindrical wall of the annular layer of the sound-absorbing material constituted by a griLLage or a metal cage holding in place a fabric with loose texture.
  • An in situ regenerable silencer in accordance with the second aspect of the invention comprises an outer casing 1 made of solid sheet which is separated, that is to say without definitive connection, from a layer of sound absorbing material 2 which it contains.
  • an interval in the radial direction which causes an annular volume 3 to appear between the outer casing 1 and the sound-absorbing material 2.
  • This annular volume 3 is closed at its opposite ends in the axial direction and it is connected to a nozzle. 4 allowing its connection to a compressed air and water supply containing a detergent.
  • the soundproofing material 2 is supported on its internal face by a fabric 5 made of loose texture synthetic fibers which is itself supported by a rigid cage made up of tubes 6; the latter are perforated in their inner part with the silencer and, outside of this, they are connected to a flexible pipe 7 terminating in an electropneumatic valve 8 which is part of a compressed air distribution network.
  • the soundproofing material 2 is supported on its external face 9 by a fabric of synthetic fibers with a loose texture, preferably identical to the fabric 5 of the internal face, which rests on a semi-rigid metallic mesh with large meshes, made of plasticized wire of preference.
  • This external retaining wall 10, not shown in detail, is spaced from the external envelope 1 by the annular volume 3.
  • FIG. 3 shows in cross section a silencer similar to that of Figures 1, 2 where the same references designate the same parts.
  • the outer casing 1 ′ made of solid sheet metal is composed of removable panels.
  • a rigid LongitudinaLe frame 11 carries hinges 12 by means of which panels 13 are pivotally mounted by one of their Longitudinal edges; The opposite LongitudinaL edge allows each panel 13 to be fixed to the frame 11, in the closed position.
  • the outer envelope 1 ′ is separated from the layer 2 of soundproofing material; however, the annular volume 3 of FIGS. 1 and 2 is no longer necessary. It is therefore possible to lining the inside of the panels 13 with a layer 14 of insulating material.
  • This FIG. 3 also shows that the rigid frame 11 is used to hold the outer wall 10 of the layer of sound-absorbing material 2 in position using spacers 15.
  • the in situ regeneration consists, with the silencer of FIGS. 1 and 2, of connecting the end piece 4 and of opening the valve 8 for cleaning and drying as explained above.
  • the silencer of Figure 3 we can either stop the fan, open all the panels 13 and send from outside using a nozzle 16 a jet of pressurized water added with a detergent, which runs in one minute per m 3 of soundproofing material 2 cleaned. The water descends through the mass of the material 2. It is advisable to attach to the lower part thereof an impermeable strip 17; by giving the entire installation a slight longitudinal slope, the washing water is collected, channeled and evacuated without difficulty.
  • the silencer of the invention differs in its construction from conventional silencers, it was useful to check the quality of sound reduction.
  • Lp 1, Lp 2, Lp 3 are The acoustic levels
  • Lp is The weighted surface sound pressure level
  • Lw is The sound power level according to standard NFS 31-021.
  • the acoustic attenuation coefficient is 22.1 dBA and for a conventional silencer it is only 18.4.
  • Figure 5 shows the different points where the acoustic levels were measured in an installation, the fan comprising a mouth silencer 18, an electric fan 19 and a conventional outlet silencer 20. All measurements were taken at 1 m walls. The results are summarized in Table 2.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Combustion & Propulsion (AREA)
  • Mining & Mineral Resources (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Geology (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Exhaust Silencers (AREA)
EP85400978A 1984-05-18 1985-05-17 In situ regenerierbarer Geräuschdämpfer für Ventilator in, mit staubhaltiger Luft geförderten Ventilationsanlagen und in situ Regenerierungsprozess dafür Expired EP0165145B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85400978T ATE36585T1 (de) 1984-05-18 1985-05-17 In situ regenerierbarer geraeuschdaempfer fuer ventilator in, mit staubhaltiger luft gefoerderten ventilationsanlagen und in situ regenerierungsprozess dafuer.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8407711A FR2564532B1 (fr) 1984-05-18 1984-05-18 Silencieux regenerables in situ pour ventilateurs dans les installations de ventilation alimentees en air empoussiere et procede de regeneration in situ de ces silencieux.
FR8407711 1984-05-18

Publications (2)

Publication Number Publication Date
EP0165145A1 true EP0165145A1 (de) 1985-12-18
EP0165145B1 EP0165145B1 (de) 1988-08-17

Family

ID=9304115

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85400978A Expired EP0165145B1 (de) 1984-05-18 1985-05-17 In situ regenerierbarer Geräuschdämpfer für Ventilator in, mit staubhaltiger Luft geförderten Ventilationsanlagen und in situ Regenerierungsprozess dafür

Country Status (5)

Country Link
EP (1) EP0165145B1 (de)
AT (1) ATE36585T1 (de)
DE (1) DE3564469D1 (de)
FR (1) FR2564532B1 (de)
IN (1) IN165301B (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2195706A (en) * 1986-06-30 1988-04-13 Tomac Mining Products Limited Fan silencers
GB2256006A (en) * 1991-05-21 1992-11-25 Harbury Holdings Inc Exhaust silencer.
WO1999013274A1 (en) * 1997-09-11 1999-03-18 Hrl Technology Pty. Ltd. An improved sound attenuating device
WO2000058659A1 (en) * 1999-03-26 2000-10-05 Paroc Group Oy Ab Muffler lining for air or gas channels
DE102005020303A1 (de) * 2005-04-30 2006-11-09 Volkswagen Ag Eine die Geräuschemission vermidernde Leitung sowie ein Verbrennungsmotor mit einer solchen Leitung

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2056608A (en) * 1933-12-22 1936-10-06 C F Burges Lab Inc Silencer
US2073951A (en) * 1935-12-09 1937-03-16 Servais Services Ltd Silencer for gaseous currents
FR2205625A1 (de) * 1972-11-04 1974-05-31 Ferroplast Gmbh
US3949830A (en) * 1975-06-20 1976-04-13 George Koch Sons, Inc. Fan silencer
FR2502244A1 (fr) * 1981-03-21 1982-09-24 Mann & Hummel Filter Procede et dispositif pour eliminer la suie des gaz d'echappement d'un moteur a combustion interne

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2056608A (en) * 1933-12-22 1936-10-06 C F Burges Lab Inc Silencer
US2073951A (en) * 1935-12-09 1937-03-16 Servais Services Ltd Silencer for gaseous currents
FR2205625A1 (de) * 1972-11-04 1974-05-31 Ferroplast Gmbh
US3949830A (en) * 1975-06-20 1976-04-13 George Koch Sons, Inc. Fan silencer
FR2502244A1 (fr) * 1981-03-21 1982-09-24 Mann & Hummel Filter Procede et dispositif pour eliminer la suie des gaz d'echappement d'un moteur a combustion interne

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2195706A (en) * 1986-06-30 1988-04-13 Tomac Mining Products Limited Fan silencers
GB2195706B (en) * 1986-06-30 1989-12-20 Tomac Mining Products Limited Fan silencers
GB2256006A (en) * 1991-05-21 1992-11-25 Harbury Holdings Inc Exhaust silencer.
GB2256006B (en) * 1991-05-21 1995-02-22 Harbury Holdings Inc An exhaust system and a silencer therefor
WO1999013274A1 (en) * 1997-09-11 1999-03-18 Hrl Technology Pty. Ltd. An improved sound attenuating device
US6622818B2 (en) 1997-09-11 2003-09-23 Hrl Technology Pty Ltd. Sound attenuating device
WO2000058659A1 (en) * 1999-03-26 2000-10-05 Paroc Group Oy Ab Muffler lining for air or gas channels
DE102005020303A1 (de) * 2005-04-30 2006-11-09 Volkswagen Ag Eine die Geräuschemission vermidernde Leitung sowie ein Verbrennungsmotor mit einer solchen Leitung

Also Published As

Publication number Publication date
FR2564532A1 (fr) 1985-11-22
DE3564469D1 (en) 1988-09-22
ATE36585T1 (de) 1988-09-15
IN165301B (de) 1989-09-16
FR2564532B1 (fr) 1986-09-12
EP0165145B1 (de) 1988-08-17

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