[{"data":1,"prerenderedAt":1160},["ShallowReactive",2],{"site-footer-common":3,"glossary:low-frequency-acoustic-cleaner":45,"glossary-related:low-frequency-acoustic-cleaner":293},{"id":4,"extension":5,"footer":6,"meta":40,"navbar":41,"stem":43,"__hash__":44},"common\u002Fcommon.yml","yml",{"tagline":7,"links":8,"sections":9},"Acoustic cleaning intelligence for industrial fouling, soot, ash, dust and build-up.",[],[10,19,31],{"title":11,"links":12},"Product",[13,16],{"label":14,"to":15},"How it works","\u002F#product",{"label":17,"to":18},"Cost assessment","\u002F#hero",{"title":20,"links":21},"Company",[22,25,28],{"label":23,"to":24},"What we build","\u002F#about",{"label":26,"to":27},"Careers","\u002F#careers",{"label":29,"to":30},"Contact","\u002F#contact",{"title":32,"links":33},"Resources",[34,37],{"label":35,"to":36},"Blog","\u002Fresources\u002Fblog",{"label":38,"to":39},"Glossary","\u002Fglossary",{},{"links":42},[],"common","YocmZRy1AYfBbpgGVms-zhdiABlF8VTxHx6h4rDmZBA",{"id":46,"title":47,"aliases":48,"body":52,"category":269,"description":270,"extension":271,"meta":272,"navigation":273,"path":274,"relatedTerms":275,"seo":281,"sources":284,"stem":291,"term":47,"__hash__":292},"glossary\u002Fglossary\u002Flow-frequency-acoustic-cleaner.md","Low-frequency acoustic cleaner",[49,50,51],"low frequency sonic horn","low-frequency horn","LF acoustic cleaner",{"type":53,"value":54,"toc":261},"minimark",[55,75,80,88,92,157,161,228,232],[56,57,58,59,63,64,69,70,74],"p",{},"A ",[60,61,62],"strong",{},"low-frequency acoustic cleaner"," is an industrial ",[65,66,68],"a",{"href":67},"\u002Fglossary\u002Fsonic-horn","sonic horn"," whose fundamental frequency sits in the 60–250 Hz band. The long acoustic wavelength — between 1.4 and 5.7 metres in air — projects further from the ",[65,71,73],{"href":72},"\u002Fglossary\u002Fbell-horn","bell horn"," than higher-frequency designs, fills large open vessels more uniformly and is the default choice for cleaning bulky industrial equipment.",[76,77,79],"h2",{"id":78},"why-frequency-choice-matters","Why frequency choice matters",[56,81,82,83,87],{},"Acoustic energy at long wavelengths diffracts around obstructions (tube banks, electrode rows, baffles) instead of being absorbed or scattered. That makes low-frequency horns the appropriate selection where the cleaning target is several metres deep and partly obstructed — most large industrial vessels fall into this category. Higher-frequency horns concentrate more energy per unit volume but lose effectiveness in deep cavities; see ",[65,84,86],{"href":85},"\u002Fglossary\u002Fhigh-frequency-acoustic-cleaner","high-frequency acoustic cleaner"," for the complementary case.",[76,89,91],{"id":90},"typical-applications","Typical applications",[93,94,95,103,115,127,134,150],"ul",{},[96,97,98,102],"li",{},[65,99,101],{"href":100},"\u002Fglossary\u002Felectrostatic-precipitator","Electrostatic precipitators"," — collecting-plate cleaning, hopper de-bridging",[96,104,105,109,110,114],{},[65,106,108],{"href":107},"\u002Fglossary\u002Fpreheater-cyclone","Preheater cyclones"," and ",[65,111,113],{"href":112},"\u002Fglossary\u002Fcalciner","calciners"," in cement plants",[96,116,117,121,122,126],{},[65,118,120],{"href":119},"\u002Fglossary\u002Frecovery-boiler","Kraft recovery boilers"," — superheaters, ",[65,123,125],{"href":124},"\u002Fglossary\u002Fgenerating-bank","generating banks",", economisers",[96,128,129,133],{},[65,130,132],{"href":131},"\u002Fglossary\u002Fair-heater","Air heater"," cold-end basket cleaning",[96,135,136,137,141,142,109,146],{},"Large ",[65,138,140],{"href":139},"\u002Fglossary\u002Ffly-ash-hopper","fly-ash hoppers",", ",[65,143,145],{"href":144},"\u002Fglossary\u002Fsilo","silos",[65,147,149],{"href":148},"\u002Fglossary\u002Fbunker-coal-bunker","bunkers",[96,151,152,156],{},[65,153,155],{"href":154},"\u002Fglossary\u002Fheat-recovery-steam-generator","HRSG harp-tube banks"," in combined-cycle plants",[76,158,160],{"id":159},"indicative-selection-bands","Indicative selection bands",[162,163,164,180],"table",{},[165,166,167],"thead",{},[168,169,170,174,177],"tr",{},[171,172,173],"th",{},"Band",[171,175,176],{},"Wavelength in air at 20 °C",[171,178,179],{},"Typical use",[181,182,183,195,206,217],"tbody",{},[168,184,185,189,192],{},[186,187,188],"td",{},"60 Hz",[186,190,191],{},"~5.7 m",[186,193,194],{},"Very large ESPs, recovery boilers, deep silos",[168,196,197,200,203],{},[186,198,199],{},"75 Hz",[186,201,202],{},"~4.6 m",[186,204,205],{},"ESPs, preheater cyclones, large hoppers",[168,207,208,211,214],{},[186,209,210],{},"125 Hz",[186,212,213],{},"~2.7 m",[186,215,216],{},"Mid-size ESPs, baghouse compartments, calciners",[168,218,219,222,225],{},[186,220,221],{},"230 Hz",[186,223,224],{},"~1.5 m",[186,226,227],{},"Boiler convective passes, smaller hoppers, baghouses",[76,229,231],{"id":230},"related-terms","Related terms",[93,233,234,239,245,250,256],{},[96,235,236],{},[65,237,238],{"href":67},"Sonic horn",[96,240,241],{},[65,242,244],{"href":243},"\u002Fglossary\u002Facoustic-cleaner","Acoustic cleaner",[96,246,247],{},[65,248,249],{"href":85},"High-frequency acoustic cleaner",[96,251,252],{},[65,253,255],{"href":254},"\u002Fglossary\u002Finfrasonic-cleaner","Infrasonic cleaner",[96,257,258],{},[65,259,260],{"href":72},"Bell horn",{"title":262,"searchDepth":263,"depth":263,"links":264},"",2,[265,266,267,268],{"id":78,"depth":263,"text":79},{"id":90,"depth":263,"text":91},{"id":159,"depth":263,"text":160},{"id":230,"depth":263,"text":231},"core-technology","A low-frequency acoustic cleaner is an industrial sonic horn whose fundamental frequency sits in the 60–250 Hz band. The long acoustic wavelength — between 1.4 and 5.7 metres in air — projects further from the bell horn than higher-frequency designs, fills large open vessels more uniformly and is the default choice for cleaning bulky industrial equipment.","md",{},true,"\u002Fglossary\u002Flow-frequency-acoustic-cleaner",[276,277,278,279,280],"acoustic-cleaner","sonic-horn","high-frequency-acoustic-cleaner","infrasonic-cleaner","bell-horn",{"title":282,"description":283},"Low-frequency acoustic cleaner — 60–250 Hz horn selection guide","Low-frequency acoustic cleaners operate at 60–250 Hz. The long wavelength penetrates deep into large open vessels such as ESPs, recovery boilers and cement preheater cyclones.",[285,288],{"title":286,"url":287},"Power Engineering — Sonic Horns: A User's Introduction","https:\u002F\u002Fwww.power-eng.com\u002Fcoal\u002Fsonic-horns-a-userrsquos-introduction\u002F",{"title":289,"url":290},"Power Engineering — Tuning in to Acoustic Cleaning","https:\u002F\u002Fwww.power-eng.com\u002Fcoal\u002Ftuning-in-to-acoustic-cleaning\u002F","glossary\u002Flow-frequency-acoustic-cleaner","m6cj771ScgiY0798OZ0cdR03A65ardaL1YsF3e8jwFM",[294,468,668,835,1033],{"id":295,"title":244,"aliases":296,"body":299,"category":269,"description":449,"extension":271,"meta":450,"navigation":273,"path":243,"relatedTerms":451,"seo":455,"sources":458,"stem":466,"term":244,"__hash__":467},"glossary\u002Fglossary\u002Facoustic-cleaner.md",[297,298],"acoustic cleaners","acoustic cleaning device",{"type":53,"value":300,"toc":443},[301,308,312,315,319,322,402,406,419,421],[56,302,303,304,307],{},"An ",[60,305,306],{},"acoustic cleaner"," is any device that uses high-intensity sound waves — typically at audible low frequencies between 60 and 450 Hz and sound pressure levels of 140 to 180 dB — to dislodge particulate fouling from inside industrial process equipment. The acoustic energy vibrates dust, ash, soot and other accreted solids, keeping them airborne and entrained in the gas flow so they cannot bond, bridge or harden on internal surfaces.",[76,309,311],{"id":310},"how-an-acoustic-cleaner-works","How an acoustic cleaner works",[56,313,314],{},"A pneumatic driver — usually compressed air at 4 to 7 bar — sets a metal diaphragm or piston-whistle assembly vibrating at the cleaner's design frequency. The vibration is amplified through an exponential bell horn and projected into the equipment as a near-spherical pressure field. Particulate already deposited on tube banks, plates, catalyst layers or hopper walls receives an oscillating force that overcomes adhesion. Because the cleaner is non-contact, it can run while the plant is online, every few minutes, without thermal shock, tube erosion or refractory damage.",[76,316,318],{"id":317},"where-acoustic-cleaners-are-used","Where acoustic cleaners are used",[56,320,321],{},"Acoustic cleaners are installed throughout the gas path and bulk-solids path of heavy industry:",[93,323,324,341,358,376,390],{},[96,325,326,329,330,141,334,141,338],{},[60,327,328],{},"Combustion plant"," — boilers, ",[65,331,333],{"href":332},"\u002Fglossary\u002Feconomiser","economisers",[65,335,337],{"href":336},"\u002Fglossary\u002Fsuperheater","superheaters",[65,339,340],{"href":131},"air heaters",[96,342,343,346,347,141,350,141,354],{},[60,344,345],{},"Air-pollution control"," — ",[65,348,349],{"href":100},"electrostatic precipitators",[65,351,353],{"href":352},"\u002Fglossary\u002Ffabric-filter","fabric filters",[65,355,357],{"href":356},"\u002Fglossary\u002Fselective-catalytic-reduction","SCR catalysts",[96,359,360,346,363,367,368,109,372],{},[60,361,362],{},"Bulk solids",[65,364,366],{"href":365},"\u002Fglossary\u002Fhopper","hoppers, silos and bunkers"," prone to ",[65,369,371],{"href":370},"\u002Fglossary\u002Fbridging","bridging",[65,373,375],{"href":374},"\u002Fglossary\u002Frat-holing","rat-holing",[96,377,378,346,381,141,384,141,386],{},[60,379,380],{},"Cement",[65,382,383],{"href":107},"preheater cyclones",[65,385,113],{"href":112},[65,387,389],{"href":388},"\u002Fglossary\u002Fkiln-inlet-riser-duct","kiln inlets",[96,391,392,346,395,141,398],{},[60,393,394],{},"Pulp and paper",[65,396,397],{"href":119},"kraft recovery boilers",[65,399,401],{"href":400},"\u002Fglossary\u002Flime-kiln","lime kilns",[76,403,405],{"id":404},"acoustic-cleaners-are-not-ultrasonic-cleaners","Acoustic cleaners are not ultrasonic cleaners",[56,407,408,409,413,414,418],{},"The two terms are routinely confused but describe completely different technologies. Acoustic cleaners operate in the audible low-frequency band and clean dry industrial surfaces ",[410,411,412],"em",{},"in situ"," with airborne sound. Ultrasonic cleaners operate above 20 kHz inside a liquid bath and clean small parts off-line by cavitation. See ",[65,415,417],{"href":416},"\u002Fglossary\u002Facoustic-cleaning-vs-ultrasonic-cleaning","acoustic cleaning vs ultrasonic cleaning",".",[76,420,231],{"id":230},[93,422,423,429,433,439],{},[96,424,425],{},[65,426,428],{"href":427},"\u002Fglossary\u002Facoustic-cleaning-system","Acoustic cleaning system",[96,430,431],{},[65,432,238],{"href":67},[96,434,435],{},[65,436,438],{"href":437},"\u002Fglossary\u002Fsonic-sootblower","Sonic sootblower",[96,440,441],{},[65,442,255],{"href":254},{"title":262,"searchDepth":263,"depth":263,"links":444},[445,446,447,448],{"id":310,"depth":263,"text":311},{"id":317,"depth":263,"text":318},{"id":404,"depth":263,"text":405},{"id":230,"depth":263,"text":231},"An acoustic cleaner is any device that uses high-intensity sound waves — typically at audible low frequencies between 60 and 450 Hz and sound pressure levels of 140 to 180 dB — to dislodge particulate fouling from inside industrial process equipment. The acoustic energy vibrates dust, ash, soot and other accreted solids, keeping them airborne and entrained in the gas flow so they cannot bond, bridge or harden on internal surfaces.",{},[452,277,453,279,454,278],"acoustic-cleaning-system","sonic-sootblower","low-frequency-acoustic-cleaner",{"title":456,"description":457},"Acoustic cleaner — definition, principle, industrial uses","An acoustic cleaner is any device that uses high-intensity sound waves to dislodge particulate fouling from inside industrial process equipment such as boilers, ESPs, baghouses and silos.",[459,462,463],{"title":460,"url":461},"Power Magazine — The Theory and Application of Acoustic Cleaners","https:\u002F\u002Fwww.powermag.com\u002Fthe-theory-and-application-of-acoustic-cleaners\u002F",{"title":289,"url":290},{"title":464,"url":465},"Wikipedia — Acoustic cleaning","https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAcoustic_cleaning","glossary\u002Facoustic-cleaner","MwPOKb4JllxnhygiJ3--SHn7B_zEw8BdkQXIXUCoV0E",{"id":469,"title":238,"aliases":470,"body":474,"category":269,"description":653,"extension":271,"meta":654,"navigation":273,"path":67,"relatedTerms":655,"seo":657,"sources":660,"stem":666,"term":238,"__hash__":667},"glossary\u002Fglossary\u002Fsonic-horn.md",[471,472,473],"sonic horns","sonic cleaning horn","industrial sonic horn",{"type":53,"value":475,"toc":646},[476,498,502,510,514,576,580,608,612,620,622],[56,477,58,478,480,481,483,484,141,487,141,490,141,492,109,495,418],{},[60,479,68],{}," is a pneumatically-driven sound emitter that produces high-intensity, low-frequency sound waves — typically between 60 and 400 Hz at sound pressure levels of 140 to 180 dB — used to dislodge particulate fouling from inside industrial process equipment. Sonic horns are the most common form of ",[65,482,306],{"href":243}," and the default specification for cleaning ",[65,485,486],{"href":100},"ESPs",[65,488,489],{"href":352},"baghouses",[65,491,357],{"href":356},[65,493,494],{"href":336},"boiler heat-transfer surfaces",[65,496,497],{"href":365},"hoppers and silos",[76,499,501],{"id":500},"how-a-sonic-horn-works","How a sonic horn works",[56,503,504,505,509],{},"Compressed plant air admitted through a ",[65,506,508],{"href":507},"\u002Fglossary\u002Fsolenoid-valve","solenoid valve"," drives a metal diaphragm — typically titanium or 316 stainless — into resonant oscillation at the horn's fundamental frequency. The oscillating pressure field is amplified by an exponential bell horn and projected into the vessel as a near-spherical sound wave. Particulate already deposited on internal surfaces receives an oscillating acceleration that overcomes adhesion; loosened material is then carried out with the gas flow before it can sinter, bridge or bond. Because the cleaning is acoustic and non-contact, the horn can fire while the plant is online without tube erosion, refractory damage or thermal shock.",[76,511,513],{"id":512},"key-parameters","Key parameters",[162,515,516,526],{},[165,517,518],{},[168,519,520,523],{},[171,521,522],{},"Parameter",[171,524,525],{},"Typical range",[181,527,528,536,544,552,560,568],{},[168,529,530,533],{},[186,531,532],{},"Fundamental frequency",[186,534,535],{},"60–400 Hz",[168,537,538,541],{},[186,539,540],{},"Sound pressure level",[186,542,543],{},"140–180 dB",[168,545,546,549],{},[186,547,548],{},"Compressed-air consumption",[186,550,551],{},"8–14 Nm³\u002Fmin at 4–7 bar",[168,553,554,557],{},[186,555,556],{},"Operating temperature (with appropriate materials)",[186,558,559],{},"−40 °C to +500 °C",[168,561,562,565],{},[186,563,564],{},"Firing cycle",[186,566,567],{},"5–15 s burst, repeated every 3–15 minutes",[168,569,570,573],{},[186,571,572],{},"Mass",[186,574,575],{},"15–60 kg depending on horn size",[76,577,579],{"id":578},"frequency-selection","Frequency selection",[56,581,582,583,141,585,588,589,141,593,595,596,141,599,603,604,109,606,418],{},"Lower frequencies (60–125 Hz) project longer wavelengths and penetrate further into large open vessels — ",[65,584,383],{"href":107},[65,586,587],{"href":119},"recovery-boiler superheaters",", large ",[65,590,592],{"href":591},"\u002Fglossary\u002Fesp-field-bus-section","ESP fields",[65,594,145],{"href":144},". Higher frequencies (230–400 Hz) carry more energy per unit volume and suit finer dust loads in ",[65,597,598],{"href":352},"fabric-filter compartments",[65,600,602],{"href":601},"\u002Fglossary\u002Fhoneycomb-catalyst","catalyst layers"," and smaller hopper geometries. See ",[65,605,62],{"href":274},[65,607,86],{"href":85},[76,609,611],{"id":610},"sonic-horn-vs-steam-sootblower","Sonic horn vs steam sootblower",[56,613,614,615,619],{},"Sonic horns are increasingly specified alongside or in place of ",[65,616,618],{"href":617},"\u002Fglossary\u002Fsteam-sootblower","steam sootblowers"," because they consume no boiler-grade steam, cause no tube erosion, require almost no moving parts and can fire every few minutes without operator intervention. They are less effective on hard, fused slag than retractable steam lances, so on furnace waterwalls and high-temperature superheaters they typically complement rather than replace mechanical cleaning.",[76,621,231],{"id":230},[93,623,624,628,632,636,642],{},[96,625,626],{},[65,627,244],{"href":243},[96,629,630],{},[65,631,438],{"href":437},[96,633,634],{},[65,635,260],{"href":72},[96,637,638],{},[65,639,641],{"href":640},"\u002Fglossary\u002Fdiaphragm-horn","Diaphragm horn",[96,643,644],{},[65,645,47],{"href":274},{"title":262,"searchDepth":263,"depth":263,"links":647},[648,649,650,651,652],{"id":500,"depth":263,"text":501},{"id":512,"depth":263,"text":513},{"id":578,"depth":263,"text":579},{"id":610,"depth":263,"text":611},{"id":230,"depth":263,"text":231},"A sonic horn is a pneumatically-driven sound emitter that produces high-intensity, low-frequency sound waves — typically between 60 and 400 Hz at sound pressure levels of 140 to 180 dB — used to dislodge particulate fouling from inside industrial process equipment. Sonic horns are the most common form of acoustic cleaner and the default specification for cleaning ESPs, baghouses, SCR catalysts, boiler heat-transfer surfaces and hoppers and silos.",{},[276,452,453,280,656,454],"diaphragm-horn",{"title":658,"description":659},"Sonic horn — definition, frequency, SPL and industrial applications","A sonic horn is a pneumatically-driven low-frequency sound emitter (typically 60–400 Hz at 140–180 dB SPL) used to dislodge particulate fouling from boilers, ESPs, baghouses and process vessels.",[661,662,663],{"title":286,"url":287},{"title":289,"url":290},{"title":664,"url":665},"Wikipedia — Sonic soot blowers","https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FSonic_soot_blowers","glossary\u002Fsonic-horn","YzrhN0kKzqSaQo0wfn0rueNZ-V43mcg5zahqeWi3lnU",{"id":669,"title":249,"aliases":670,"body":674,"category":269,"description":821,"extension":271,"meta":822,"navigation":273,"path":85,"relatedTerms":823,"seo":825,"sources":828,"stem":833,"term":249,"__hash__":834},"glossary\u002Fglossary\u002Fhigh-frequency-acoustic-cleaner.md",[671,672,673],"high frequency sonic horn","HF acoustic cleaner","high-frequency horn",{"type":53,"value":675,"toc":814},[676,688,692,712,716,754,758,769,773,788,790],[56,677,58,678,680,681,683,684,687],{},[60,679,86],{}," is a ",[65,682,68],{"href":67}," operating in the upper end of the audible industrial-cleaning band, typically 250 to 450 Hz. The shorter wavelength — 0.75 to 1.4 metres in air — couples more energy into smaller geometries and finer dust loads than long-wavelength ",[65,685,686],{"href":274},"low-frequency horns"," can deliver.",[76,689,691],{"id":690},"where-high-frequency-horns-earn-their-place","Where high-frequency horns earn their place",[56,693,694,695,698,699,702,703,707,708,711],{},"The cleaning target dictates the choice. Where deposits are fine and surfaces are densely packed — ",[65,696,697],{"href":352},"fabric-filter"," bag rows, ",[65,700,701],{"href":601},"honeycomb SCR catalyst"," cell faces, small ",[65,704,706],{"href":705},"\u002Fglossary\u002Fcyclone-separator","cyclone separators",", tight ",[65,709,710],{"href":131},"air-heater"," basket geometries — the higher energy density of a 250–450 Hz horn lifts particulate more reliably than a long wave that would diffract past it.",[76,713,715],{"id":714},"selection-guide","Selection guide",[162,717,718,728],{},[165,719,720],{},[168,721,722,725],{},[171,723,724],{},"Frequency",[171,726,727],{},"Best for",[181,729,730,738,746],{},[168,731,732,735],{},[186,733,734],{},"250 Hz",[186,736,737],{},"Mid-size baghouse compartments, smaller boiler convective passes",[168,739,740,743],{},[186,741,742],{},"350 Hz",[186,744,745],{},"SCR catalyst layers, fine-particulate fabric filters",[168,747,748,751],{},[186,749,750],{},"400–450 Hz",[186,752,753],{},"Compact hoppers, fine-cell honeycomb catalysts, small ducting",[76,755,757],{"id":756},"construction-differences-from-low-frequency-horns","Construction differences from low-frequency horns",[56,759,760,761,763,764,768],{},"A higher fundamental frequency means a smaller ",[65,762,73],{"href":72}," cut-off and therefore a physically smaller, lighter unit — useful where mounting clearance is tight or where a large array of horns must be distributed across a baghouse roof. High-frequency designs are often ",[65,765,767],{"href":766},"\u002Fglossary\u002Fpiston-whistle-horn","piston-whistle"," rather than diaphragm-driven, with a different wear profile and shorter individual firing bursts.",[76,770,772],{"id":771},"when-to-step-down-to-low-frequency","When to step down to low frequency",[56,774,775,776,141,778,141,780,141,782,784,785,787],{},"For deep, open vessels and bulk-solids storage — ",[65,777,486],{"href":100},[65,779,383],{"href":107},[65,781,145],{"href":144},[65,783,587],{"href":119}," — a ",[65,786,50],{"href":274}," projects further and is normally specified instead. Many real installations combine both bands: low-frequency horns clean the bulk volume; high-frequency horns clean the dense bag rows or catalyst faces nearby.",[76,789,231],{"id":230},[93,791,792,796,800,804,809],{},[96,793,794],{},[65,795,238],{"href":67},[96,797,798],{},[65,799,244],{"href":243},[96,801,802],{},[65,803,47],{"href":274},[96,805,806],{},[65,807,808],{"href":766},"Piston-whistle horn",[96,810,811],{},[65,812,813],{"href":352},"Fabric filter",{"title":262,"searchDepth":263,"depth":263,"links":815},[816,817,818,819,820],{"id":690,"depth":263,"text":691},{"id":714,"depth":263,"text":715},{"id":756,"depth":263,"text":757},{"id":771,"depth":263,"text":772},{"id":230,"depth":263,"text":231},"A high-frequency acoustic cleaner is a sonic horn operating in the upper end of the audible industrial-cleaning band, typically 250 to 450 Hz. The shorter wavelength — 0.75 to 1.4 metres in air — couples more energy into smaller geometries and finer dust loads than long-wavelength low-frequency horns can deliver.",{},[276,277,454,824,697],"piston-whistle-horn",{"title":826,"description":827},"High-frequency acoustic cleaner — 250–450 Hz horns for fine dust","High-frequency acoustic cleaners operate at 250–450 Hz. The shorter wavelength carries more energy per unit volume and suits fabric filters, SCR catalysts and small hopper geometries.",[829,830],{"title":286,"url":287},{"title":831,"url":832},"Micronics — Sonic Horns for Baghouses","https:\u002F\u002Fwww.micronicsinc.com\u002Fdry-baghouse-filtration\u002Fparts\u002Fbaghouse-accessories\u002Fsonic-horns\u002F","glossary\u002Fhigh-frequency-acoustic-cleaner","lNIvkPALQGjCAhpfwsyKTlK4g-5X34MBQgtefiuEWTM",{"id":836,"title":255,"aliases":837,"body":841,"category":269,"description":1018,"extension":271,"meta":1019,"navigation":273,"path":254,"relatedTerms":1020,"seo":1023,"sources":1026,"stem":1031,"term":255,"__hash__":1032},"glossary\u002Fglossary\u002Finfrasonic-cleaner.md",[838,839,840],"infrasound cleaner","infrasonic cleaning system","sub-audible acoustic cleaner",{"type":53,"value":842,"toc":1012},[843,858,862,952,956,975,979,986,988],[56,844,303,845,848,849,851,852,854,855,857],{},[60,846,847],{},"infrasonic cleaner"," (also written ",[410,850,838],{},") is an ",[65,853,306],{"href":243}," that operates below the threshold of human hearing — typically 12 to 30 Hz, against the 60–400 Hz range of a conventional ",[65,856,68],{"href":67},". The very long wavelength of an infrasonic wave (above 10 metres at 30 Hz) fills a large vessel almost uniformly and penetrates further into deep, baffled or obstructed cavities than higher-frequency horns can reach.",[76,859,861],{"id":860},"how-it-differs-from-a-sonic-horn","How it differs from a sonic horn",[162,863,864,875],{},[165,865,866],{},[168,867,868,871,873],{},[171,869,870],{},"Attribute",[171,872,255],{},[171,874,238],{},[181,876,877,887,898,909,920,931],{},[168,878,879,881,884],{},[186,880,724],{},[186,882,883],{},"12–30 Hz (sub-audible)",[186,885,886],{},"60–400 Hz (audible)",[168,888,889,892,895],{},[186,890,891],{},"Wavelength",[186,893,894],{},"10–28 m",[186,896,897],{},"0.85–5.7 m",[168,899,900,903,906],{},[186,901,902],{},"Penetration",[186,904,905],{},"Excellent, fills the whole vessel",[186,907,908],{},"Directional, projected from the bell",[168,910,911,914,917],{},[186,912,913],{},"Audible noise at the work area",[186,915,916],{},"Very low (mostly inaudible)",[186,918,919],{},"Significant, often requires hearing protection",[168,921,922,925,928],{},[186,923,924],{},"Bell size",[186,926,927],{},"Large (low cut-off frequency demands physical bulk)",[186,929,930],{},"Compact",[168,932,933,935,949],{},[186,934,91],{},[186,936,937,141,940,944,945,948],{},[65,938,939],{"href":119},"Recovery boilers",[65,941,943],{"href":942},"\u002Fglossary\u002Fwaste-to-energy","WtE"," flue paths, ",[65,946,947],{"href":154},"HRSGs",", marine boilers",[186,950,951],{},"Cross-application; default specification",[76,953,955],{"id":954},"where-infrasonic-cleaners-are-preferred","Where infrasonic cleaners are preferred",[56,957,958,959,961,962,966,967,970,971,974],{},"Infrasonic technology was popularised by Swedish suppliers (Infrafone \u002F Heat Management) on pulp-and-paper ",[65,960,397],{"href":119},", where the combination of deep superheater cavities and the strict need to extend the interval between ",[65,963,965],{"href":964},"\u002Fglossary\u002Fchill-and-blow","chill-and-blow"," wash cycles rewards the deeper penetration of long waves. The same logic carries over to large ",[65,968,969],{"href":942},"WtE boilers"," with sticky chloride-laden ash, to ",[65,972,973],{"href":154},"HRSG harp tube banks"," and to large marine boilers where work-area noise must be kept low.",[76,976,978],{"id":977},"when-to-choose-a-sonic-horn-instead","When to choose a sonic horn instead",[56,980,981,982,985],{},"For most baghouse, ESP, hopper and silo applications, a 60–250 Hz ",[65,983,984],{"href":274},"low-frequency sonic horn"," projects enough penetration with a smaller bell, lower capital cost, lower air consumption and simpler integration. Infrasonic cleaners earn their cost where vessel geometry, deposit depth or noise-exposure limits make the long wavelength specifically valuable.",[76,987,231],{"id":230},[93,989,990,994,998,1002,1007],{},[96,991,992],{},[65,993,244],{"href":243},[96,995,996],{},[65,997,238],{"href":67},[96,999,1000],{},[65,1001,47],{"href":274},[96,1003,1004],{},[65,1005,1006],{"href":119},"Recovery boiler",[96,1008,1009],{},[65,1010,1011],{"href":942},"Waste-to-energy",{"title":262,"searchDepth":263,"depth":263,"links":1013},[1014,1015,1016,1017],{"id":860,"depth":263,"text":861},{"id":954,"depth":263,"text":955},{"id":977,"depth":263,"text":978},{"id":230,"depth":263,"text":231},"An infrasonic cleaner (also written infrasound cleaner) is an acoustic cleaner that operates below the threshold of human hearing — typically 12 to 30 Hz, against the 60–400 Hz range of a conventional sonic horn. The very long wavelength of an infrasonic wave (above 10 metres at 30 Hz) fills a large vessel almost uniformly and penetrates further into deep, baffled or obstructed cavities than higher-frequency horns can reach.",{},[276,277,454,1021,1022],"recovery-boiler","waste-to-energy",{"title":1024,"description":1025},"Infrasonic cleaner — sub-20 Hz acoustic cleaning for deep penetration","An infrasonic cleaner operates below the audible threshold (typically 12–30 Hz). The very long wavelength penetrates further than a conventional sonic horn and is preferred on recovery boilers and WtE flue paths.",[1027,1030],{"title":1028,"url":1029},"Heat Management — Infrasound Cleaning for Boiler Efficiency","https:\u002F\u002Fheatmanage.com\u002Fknowledge\u002Funlocking-infrasound-cleaning-data-for-boiler-efficiency\u002F",{"title":460,"url":461},"glossary\u002Finfrasonic-cleaner","Oqfo1uKF8ioWxXKH687wPi188BqvEoa3EWC_w2jXmG4",{"id":1034,"title":260,"aliases":1035,"body":1039,"category":269,"description":1146,"extension":271,"meta":1147,"navigation":273,"path":72,"relatedTerms":1148,"seo":1150,"sources":1153,"stem":1158,"term":260,"__hash__":1159},"glossary\u002Fglossary\u002Fbell-horn.md",[1036,1037,1038],"bell-shaped horn","exponential bell horn","exponential horn",{"type":53,"value":1040,"toc":1141},[1041,1056,1060,1074,1078,1119,1121],[56,1042,58,1043,1045,1046,1048,1049,1052,1053,1055],{},[60,1044,73],{}," is the conical or exponential flare bolted to the driver of an industrial ",[65,1047,68],{"href":67},". Its job is to transform the high-impedance, small-area pressure pulse from the ",[65,1050,1051],{"href":640},"diaphragm"," or ",[65,1054,767],{"href":766}," into a lower-impedance, larger-area sound wave that couples efficiently into the gas inside the vessel.",[76,1057,1059],{"id":1058},"why-the-geometry-matters","Why the geometry matters",[56,1061,1062,1063,1065,1066,1052,1070,1073],{},"The bell is not decorative. Its flare profile — usually exponential, sometimes catenoidal or tractrix — sets the horn's cut-off frequency: below the cut-off, the bell stops behaving as a horn and the radiated sound power collapses. A 60 Hz ",[65,1064,62],{"href":274}," therefore needs a physically larger bell than a 230 Hz unit, which is why low-frequency horns are noticeably bulkier and heavier. Mounting orientation, flange standard (",[65,1067,1069],{"href":1068},"\u002Fglossary\u002Fflange-standards-dn-ansi","DN",[65,1071,1072],{"href":1068},"ANSI 150",") and the bell's projection distance into the vessel are all selected to match the cleaning target geometry.",[76,1075,1077],{"id":1076},"materials","Materials",[93,1079,1080,1091,1100],{},[96,1081,1082,1085,1086,109,1088],{},[60,1083,1084],{},"Carbon steel"," for ambient-temperature mounting on cool-side ducts, ",[65,1087,145],{"href":144},[65,1089,1090],{"href":365},"hoppers",[96,1092,1093,1099],{},[60,1094,1095],{},[65,1096,1098],{"href":1097},"\u002Fglossary\u002Faisi-316-316l-stainless","316 stainless steel"," for corrosive or food-grade environments",[96,1101,1102,1108,1109,141,1112,1115,1116,1118],{},[60,1103,1104],{},[65,1105,1107],{"href":1106},"\u002Fglossary\u002Finconel-625-718","Inconel 625 or 718"," for hot-side service above 350 °C, including ",[65,1110,1111],{"href":356},"SCR reactors",[65,1113,1114],{"href":131},"air heater"," penthouses and ",[65,1117,1021],{"href":119}," flue paths",[76,1120,231],{"id":230},[93,1122,1123,1127,1131,1135],{},[96,1124,1125],{},[65,1126,238],{"href":67},[96,1128,1129],{},[65,1130,641],{"href":640},[96,1132,1133],{},[65,1134,808],{"href":766},[96,1136,1137],{},[65,1138,1140],{"href":1139},"\u002Fglossary\u002Facoustic-horn","Acoustic horn",{"title":262,"searchDepth":263,"depth":263,"links":1142},[1143,1144,1145],{"id":1058,"depth":263,"text":1059},{"id":1076,"depth":263,"text":1077},{"id":230,"depth":263,"text":231},"A bell horn is the conical or exponential flare bolted to the driver of an industrial sonic horn. Its job is to transform the high-impedance, small-area pressure pulse from the diaphragm or piston-whistle into a lower-impedance, larger-area sound wave that couples efficiently into the gas inside the vessel.",{},[277,656,824,1149],"acoustic-horn",{"title":1151,"description":1152},"Bell horn — definition, geometry and role in acoustic cleaning","A bell horn is the conical or exponential flare that amplifies and projects sound from an industrial sonic horn's driver into the vessel being cleaned.",[1154,1157],{"title":1155,"url":1156},"Wikipedia — Horn (acoustic)","https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FHorn_(acoustic)",{"title":460,"url":461},"glossary\u002Fbell-horn","gKEabZrcxtpNiaEXB65PC50sPq3KHeDc-fyn9OvYp4I",1782613733406]