Document Gm99rp1x5ygyZGjmYe4g21Z1m

FILE NAME: Engineering (ENG) DATE: 1959 DOC#: ENG007 DOCUMENT DESCRIPTION: Book Excerpt - Design of Industrial Exhaust Systems DESIGN OF INDUSTRIAL EXHAUST SYSTEMS How to Design, Build or Buy an Exhaust System that W ill A dequately and Economically Perform the Func tions Required by Law or Prescribed by Specialists. Covers Exhaust Ventilation, Low-Pressure Pneumatic Conveying, Hood Design, Piping and Structural Details, and Selection of Dust Separators and Exhaust Fans. By JO H N L. A LD EN Member, American Society of Mechanical Engineers HIRD EDI, C N Srs* Pr,m n c THE INDUSTRIAL PRESS 93 WORTH STREET, NEW YO R K 13, N Y. Publishers of AIR C O N D IT I O N IN G , HEATING AND VENTILATING CTopHyErigINhtD,UST19R3I9A, L19P48R,E1S9S59 New York 13, N. Y. Library of Congress Catalog Card Number: 59-13381 PRINTED IN THE "UNITED STATES OF AMERICA PREFACE This book makes no attempt to cover the broad fields of health hhayzgaierndes., iAnbdluestirnivael sdtiugsattsoorrs thhaevpeaethxtoelnogdiecdalthpehahsoesrizoofninodfusthtreisael sinufbojremctesdiomfmtheennseeleydifnorreexchenatusytesaarnsi.taItnidouns.tIrtyi,s tnhoetrwefeolrlein, fiosrmweeldl ateslltothheoewngbiensetetrohsoawtitsofydtehsiagtnnaenedd. bTuhiledpourrhpoowsetoofbtuhyisabnoeoxkhiasutsot stiyosntesmprtehscartibweidllbaydtehqeuaintedluysatrnidalehcyognioemneiceaxllpyerpterofrobrmy lathwe. func 90Ayletharosugahndexhhaasusbteveenntrielcaotigonnizheads bbyeesntaptruatcetifcoerd fmoorrme otrheantha6n0 years, the literature is astonishingly scanty. There seem to have btieveenlytwsmo amllaajonrdcionncotrnisbpuitciunogufsaactnodrsh.aFsinrsott,atthteraficetleddhtahsebaetetnenrteiolan opferchoallpesgepsreadnodmoitnhaenrt,infadcetpoerndheans tbienevnestthigatatmorasn. yTohfethseocsoenwd,itahnind tshecerientdsutsotrbyehadviveutlrgeeadtendetihtheeirratcocucmomulpaetetidtodrastanaors ptorecciuosutsomtreardse. wThoerkauatnhdortoaeimxpsrteossdimspaenlym-oofstthoef ttrhaedme yssetcerreytssuinrrsotruanidgihntg-feoxrhwaaursdt tehnigsinbeoeorkinbguttebremlise.veHsethisatfusullfyficcioennstcdioautsa ohfavtehebesehnorptrceosmenintegds otof pcoemrmpiettitthiveeddeseisgignnosfaanddeqthueatcelaainmdsloofwr-icvoasltcsoynsttreamcstoorrs.toItaips phroapiesde tehnagtintheeerrineagdfearcwtsilclobneceernncionugraegxehdautostmsyeastseumres, troectohredeannddthpautbloiushr croellilaebctleio.n of basic data will become more complete and more The subject of exhaust ventilation embraces the theory of air tfiloown,otfhecoampmpleicractiiaolnfaonfsthainsdthdeuosrtyctoollepcrtaocrtsi,cathl edecsoignnst,rtuhcetiosenleocf tishenophlaycskicoafl ppulabnlitshaenddmthaetetreisatlinogn othfethsuebcjoemctpolefteflduisdyfsltoewm..UTnhfeorre tbuenfaotuenlyd,itnhpeaipnefrosrmnoattieoansiliys awcicdeeslsyibslceattotetrheedbaunsdy emnugcihneoefr.itMiosrteo oinvteern, smivaensytucdoyntfoursiencgonccoilnetcroandficlitcitoinnsg satraeteemnceonutsntaenrdedc,onrcelquusiiroinnsg. Tthheetahuetohroertichaalspsoerletciotends aonfdthaebrbiodogke.d the most authentic data for Ac&knVowledgment,swarheodguueidteodCp.oHrt.iBon. sHooftcthhkeimss,ateri1aol rt,hroeuagh isnergial puebnlticialtaitoinn,gand to E. J. Crane, Western Electric o., nc., for his advice and criticism of the earlier chapters. PREFACE TO SECO ND EDITION adIvnantchees ainntderrveefnininemg eynetasrisn seixnhcaeutshtissysbtoeomk pwraasctifciressthpauvbelitsahkeedn, phlaavcee.beIennrperceopganrietidonasowfetlhl eassemdaenvyelloepsmseernatsd,dtitwioonsn.eTwhechgaropwtetrhs ooff meleecttarloschhaesmwicaarlrapnrotecdesbsreosafdoerrsturrefaatcme epnrtepoaf rfautmioencaonndtrfoiln.iAshxiinagl floIwnfa1n91s,4atlhsoe, ahuatvheoarcqinusitraeldlendewa itmripaol retxahnaceusint uexnhitauonst awogrrka.nite sduevrfealocpinedg mbeaccahuinsee ionf Bwaorrrke,erVeorpmpoonsitt.ioTnh. isItunisi,t wthaesrenfeovreer, fwuiltlhy ceoffnosritdseroafbloethpeerrssownhalosseatpisefrascitsitoennctehaint hreecreenptorytesarthsehsausccgeasisnfeudl accAeppptarneccieaotifonexihsaduuset tporoMteiscstiGonraicnetNhe. Dstoonnoevcaunt,tLinibgrianrdiuanstroyf.the iKneraerandyinWgoarnkds oafbsthtreaWctiensgtetrhne Eselevcetrrailc hCuon.,dIrnedc.,tefochrnhiecralpaarttieicnlcees reviewed in the preparation of the second edition of this book. PREFACE TO THIRD EDITION in Sthinecevpauribeltiycatainodn oqfutahlietyseocofnddeevdiciteisonavaadivlaabnlceestohatvheebeenengimneaedre. Femorpthhaesims oosntipnadrutstthreiaylhhayvgeiecnoem. eInadbouusttraiaslafirremsuslatroef ltehses irneclruecatsaendt tlionsepsse.ndTthhee dsuevmeslonpemceesnstaroyftofosgecufirlteerasd,eqruevaetersaetmflooswphfeilrtiecrcsleaannd vtuernetucryicslcornuebsbaerres annodtitcheeabinlecraedavseadncaeps.plAicarteiocnenotf emxuamltiipnlaetmioinnioaf a1p70p0repciaatteinonts orfelsaotuenddteongdiunsetercionngtrporlindceivpilceessonshtohwes pianrctreoafsitnhge itnevxetnttoorasc.-coAudndtitfioornathl emseatcehraianlgpesr.esented herein updates the basic March, 1959 J. L. A. VI CONTENTS 1 Flow of Fluids 1 --FunScutsiopnensdoefdthSoeliCdson--veySitnagticF,luViedlo--cityStaannddaIrmdpAacirt P--resCsoumrepsr--essiUbinliittys oRfesPisrteasnscuere--, VMeelaoscuitryemanendt VofoluPmreess--uresSt--atiRcelPartieosnsuoref VaelMoceiatysurPereosi sCurrietictaol VVeelloocciittyy ---- BEemrpnioruicilalil'sFrTihcetioornemFo--rmNulaatsu--re RofeyFnloulidds'FDloiwme--n sFiloonwalAAlwnaalyyssiTs u--rbuRleenytnoinldsExNhuamubsterSy--steCmrsiti--calPRipeeynForlidcstioNnuminbLeram-- inar and Turbulent States -- Velocity Distribution -- Flow of Mixtures 2 Hoods for Dust Control 17 HRoeloadtiTveypDeuss--t HGaeznaerrdal--RuDleisspfeorrsiDonesoigfnDoufstMs a--chiLnoecHalooAdisr --MoDvuemstesn--ts aTnydpiCcaoluHntoeordacCtionngtoVuerlsoc--itieRse--latioEnffeocftiFvaenceesAs roefaStuocVtioenlocOitpye--ningSsum-- mReaarry ooffFHacoeod--FFaclaengCehdarHaocotedriFstaiccses---- EInfffelucetnocef oHfoAoddjaSctreuncttuPrlaeneins --HooHdoso--ds fHoorotdhsefCorapWtuoroedowfoCrkoianrgseMPaacrhtiincleersy----SSoamwe HToyopdicsa--l ESxhhaapuesrt HSuorofdasce--CPultatenrerHHooodosds----HSoaonddsefrorHoHoadnsd--ToGorlsan--iteHCouptptienrgs --HoModissce--l laneous Machine Hoods 3 Hoods for Fume, Smoke and Vapor Control 41 --CanMopuyltiHploeodSsuc--tioDnoCubolnenHecotioodnss---- FSaecmei-VCealoncoiptiieess --for RCeaanropHyooHdoso--ds --LatBeroaolthTsa--nk BEexnhcahuHsto--odsS--lotFVoeulnodcirtyiesSh--akeB-lOowut-san--d-EWxehladuinstg HFouomdes Control 4 Air Flow Through Hoods 63 FAairceVVeleolocictiiteisesR--eqPuiipreedSaiztesDaunsdt SHoouordceSsu--ctioEnx--ploAriirngVoHluomodes E--nteHroinodg HProeosdsu--resCoaetffaiciSenutctoiofnEnOtpreyn--ingT--ypiEcaffleOctriofifceSsuapnpdreNssoezdzleCso--ntraScttaiotinc --CoeEffnictireyntCsooefffiTcyiepnitcsaol fHHooododss----TSyypnicthaeltFicloEwntCraylcCuolaeftfiiocniesn--ts --MeEthnotrdys of Increasing Flow Through Hoods 5 Pipe Resistance 90 CRoecntvaenyginuglarVePliopceisty----FrSipcteicoinal LCoossnsoidferMatiixotnusre--s --Fr"iVcteioloncitLyosHseaind Vll 8 HOODS FOR DUST CONTROL 2. Place the hood as close to the source of contamination as po3s.siLbolec,aptereafnerdasbhlyapeencthloesihnogodit.so that the dust particles thrown fro4m. Cthauesseoauirrcetoarfleowdirpeacsttedthientdoutshtesomuorucethaonfdtihnetobrtahnechhopoidpew.ith easvcealpoeciotyf tahtethpearptoicinlets.of dust origin greater than the velocity of sou5r.cSeoaloncdattehethheohoodo.d that the operator is never between the dust reqMuaircehinseomheowodhsatindteinffdeerdenftordetshiegnretdeucchtnioiqnueof thheaanlthdohaztharodses isnizsetaollfedthfeordurestfupsaerrtiecmleovwahlipchurepaocshes.tyTpheeisdidsteisnicgtnioedn ltioeshianndthlee. Dsiounstsswphreormeaostiinngduocstcruipaal trieofnuasledmisaeyasiencalruedemaichroigshcoppeicrcienntdaigmeeonf large and heavy bodies. DuIsttsis believed that the practical maximum limit of inspired dusts craelnantiovteblye fmewuchpaorvteircle2s0 omviecrro1n0s1minicrloonnsgeastredifmouennsdioinn. Isnilicfaoctitc, slutanngtsi.aSl oqmuaenatuittihesoroiftidesusdtosufbintetrhtehraente0n.5tiomnicirnonthse. Rluenggasrdolfesssuobf ctheertaqiunelsytioanmoafxaimpuomssilbilme iltowanedr ltihmaitt loimf ditanisgevreoruys ssmizael,l tihnedreeedis. Etiaxlplyrelsessesdthinansh0o.0p01terinm. sl,onthge. Idtaanpgpeeraorusstphaarttniculemsbaerres aolfl psuabrtsitcalens orafthheeraltthhahnaztoatradls.wTeihguhst, oitf idsursetpiosrsteigdnitfhicaatnotfincetrhteainevafoluuantdiorny oduusstssizine,ve1s0timgaitcerdo,n9s9o%r ,fibnyern,uwmhbeerreaosf pthaersteiclpeas,rtwicelrees ocfomdapnrgiseerd but 27 % of the total weight of the samples. The author makes no pretense of treating the pathological masopreectrseocefndtulsittseraantdurfeumbeesc. oIntsuislterdec. oImt mmeunsdtedbestrreocnogglnyiztehdatththaet kfinelodwhleadsgbeeeonf cduulstitvsaatendd itnhteeinrsievfefleyc,tshoiswefaverr,fraonmd mcoumchplevtael.uaTbhlee mcoantterroilalinhhaaszbaerednoupsuibnldisuhsetdr.ieTs hweilelndgoinweeelrl tcoonicnefronremd hwimithseldfuostf the latest results available. ll micron = 1/1000 millimeter -- 0.00003937 in. DUST DISPERSION 19 Relative Dust Hazard triWal hdiluesatsu,thaofreitwiesadreiffkernoaws nto dthefeinhiaterlmy ftuolnbeesshoafzcaerrdtoauins. inCdhuiesf atemreodnginthinesdeuisstrsiieliscaa,s odcicsusirmriinlagrcaosmgmroannliyteacsuqtutianrgtza.nIdt ihsaerndc-rooucnk msuicnhinags soanntdhbelaonsteinhganadndagnrdintdhionsge oenmtphleoyoitnhgera.bArasbsievsetops,roaclseos,seiss known to produce pulmonary disability. areThheaztaorxdicoudsuwsths,enincinluhdailnedg. lIenadf,amcte, rtchuerrye, iasrsceonnicsidaenrdaboletheervsi, gdreenacteetrhtahtatnhtehlaiktetlhihroooudghoffopoodiscoonnitnagmtihnraotiuognh. inhalation may be Coal dust alone is believed not to produce disabling fibrosis. mCaalrcbiulem, daonldommitaegnanesdiummagcnaersbiotenahtaevseasbereenprsehsoewntnedtobbyelicmomesptoanrae, atinvdelywohoadrmallessos.aTreheinvetgheitsabclaetedguorstys. sHucohweavserc,otltaocnk,injugtep,ohsietmivpe ietviisdednacnegtehraotusa agnivdentodpursotviisdneoatdheaqrumatfeupl,riottiesctbioesnt. to assume that Dispersion of Dusts The manner and degree of dispersion of dust is a function of pbeardtiisctlreibsiuztee.dLoavregreapwaridtieclaersetahrboywvnirtfuroemofathwehireeklionretcicutetnerermgiaeys and without assistance from air currents. Small particles, on the odtihspeerrshiaonnd. ,Tahreemdaespsenodf eanttineyntpiraerltyicluepiosnsoaisrmcaullrraenndtsthfeorkitnheetiirc veneleorcgiytysroapliitdtlley tahnadt citanisnoitncbaepapbrloejeocftedsusftaarinferdomfligthhet. pIotinlotseosf generation.2 ThFeiinredidsupsetrssiionn sduesppeenndssioanlmdorsifttewntiitrheltyheupgoennedrrailfta. iFr incuerdreunsttss,. tinhgeraeifro.rCe,omarusestpbaerctiocnletrso, lolendthbey ccoonnttrraorllyin, gartehebfultowlitotlfethafefeecntterdaibny jloeccatilocnurrreeqnutisreosf tmhialdt tihnetenhosiotdy.bTehpeliarcdedis,ptearrsgioent-lbikyed, ysnoamthiactptrhoe particles are thrown directly into the pipe mouth. ab2oAut110imn.icirnonstialbl raairs.ivAetptahretiscalemtehrsopweendfaropmaratiwclhee1e/l1a6t i1n0.,0d0i0amf.ept.emr.mcaany fblye thrown 100 ft.