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英文原文EsignofSpeedBeltConveyorsG.Lodewijks,TheNetherlands.Thispaperdiscussesaspectsofhigh-speedbeltconveyordesign.Thecapacityofabeltconveyorisdeterminedbythebeltspeedgivenabeltwidthandtroughingangle.Beltspeedselectionhoweverislimitedbypracticalconsiderations,whicharediscussedinthispaper.Thebeltspeedalsoaffectstheperformanceoftheconveyorbelt,asforexampleitsenergyconsumptionandthestabilityofitsrunningbehavior.Amethodisdiscussedtoevaluatetheenergyconsumptionofconveyorbeltsbyusingthelossfactoroftransport.Withvariationofthebeltspeedthesafetyfactorrequirementsvary,whichwillaffecttherequiredbeltstrength.Anewmethodtoaccountfortheeffectofthebeltspeedonthesafetyfactorispresented.Finally,theimpactofthebeltspeedoncomponentselectionandonthedesignoftransferstationsisdiscussed.Beltmachinebyconveyorbeltcontinuousorintermittentmotiontotransportallkindsofdifferentthings,Cantransportallkindsofbulkmaterials,butalsotransportavarietyofcardboardboxes,packagingbags,weightofsinglepiecesofsmallgoods,awiderangeofuses.Beltconveyorbeltmaterial:rubber,silicone,PVC,PUandothermaterials,inadditiontoordinarymaterialconveying,butalsotomeetthetransmissionoilresistant,corrosionresistance,antistaticandotherspecialrequirementsformaterial.Beltconveyorstructure:groovebeltmachine,flatbeltconveyor,climbingbeltmachine,turningmachinesandotherformsbelt,conveyorbeltcanalsobecreatedtoenhancethetailgate,skirtsandotheraccessories,canmeetavarietyoftechnologicalrequirements.Thebeltconveyordrive:decelerationmotordrive,electricdriveroller.Beltconveyormode:frequencycontrol,steplesstransmission.Thebeltrackmaterial:carbonsteel,stainlesssteel,aluminumprofile.Scopeofapplication:lightindustry,electronics,food,chemical,wood,etc.Beltmachineequipmentcharacteristics:beltconveyorisstable,thematerialandtheconveyorbeltthereisnorelativemotion,toavoiddamagetothecarriermaterial.Lownoise,suitableforquietworkenvironmentrequirements.Simplestructure,easymaintenance.Lowenergyconsumption,lowusecost.Conveyorisacommondonthaveflexibletractioncomponentcontinuousconveyingmachinery,alsocalledcontinuousconveyor.Itisamaterialhandlingequipment,itwithhandlingabilitystrong,persistent,direction,flexible,andotheradvantagesinindustrialproductioninlargebeingapplied.Althoughmanytypesofbeltconveyor,butitsworkingprincipleisbasicsimilar,mostaredrivingdraughtdeviceanddrivetransmissioncontainertransportmaterials.Conveyorcanundertakelevel,thetiltandverticalconveyor,alsocanmakethespacetransportroutes,transmissionlinesisusuallyfixed,isamodernproductionandlogisticstransportindispensableimportantmechanicalequipment.Ithastransmissioncapacityisstrong,longdistancetransportationetc.Withthedevelopmentofindustry,conveyoralsoobtainedfastdevelopment,conveyorproductshavebeenalsograduallyimproved.Withtheemergenceofthepowerequipmentofsimilarprincipleisapplied,conveyorcontinuingintothe19thcentury,britonsusebasketwork,wireropefortractionbeltconveyor.Theprincipleofbeltconveyor,whenappliedinthe17thcenturyalsorecordedconveyor,in1880Germancompanydevelopeddrivenbysteambeltconveyor.ThentheBritishandGermanandlaunchedinertialconveyor,iftheconveyorbelt,theapplicationoftheprinciple,creatingatiltofthebeltconveyor,belt,tractionwithchains.Allsortsofconveyorduringthistimeariseconveyor,basedonhuman,hydraulicpowerdrivesuch.Allthestructuresconveyorsuccessivelyappeared.In1887americansproducedthescrewconveyor,makeenterpriseinternal,betweenenterpriseandinter-citytransportationpossible.Thedevelopmenthistoryofbeltconveyor,theyveryancientinsteadoftheoriginalmotiveforconveyorprovidedrivingforce.AncientpeoplebegantousewateroverturnedandhighTongCheconveyor,inturnafterthewaterconservancyprojectsbeltconveyorbegininpower.Quick-temperedexaltsAccordingtothemodeofoperationconveyingmachinerycanbedividedinto:1:beltconveyor2:screwconveyor3:doupatternliftmachineThefutureoflargescale,willtowardbeltusescope,energyconsumption,lowpollutionless,materialautomaticallygrading,etc.Pastresearchhasshowntheeconomicalfeasibilityofusingnarrower,fasterrunningconveyorbeltsversuswider,slowerrunningbeltsforlongoverlandbeltconveyorsystems.SeeforexampleI-5.Today,conveyorbeltsrunningatspeedsaround8m/sarenoexceptions.However,velocitiesover10m/supto20m/saretechnically(dynamically)feasibleandmayalsobeeconomicallyfeasible.Inthispaperbeltspeedsbetweenthe10and20m/sareclassifiedashigh.Beltspeedsbelowthe10m/sareclassifiedaslow.Usinghighbeltspeedsshouldneverbeagoalinitself.Ifusinghighbeltspeedsisnoteconomicallybeneficialorifasafeandreliableoperationisnotensuredatahighbeltspeedthenalowerbeltspeedshouldbeselected.Selectionofthebeltspeedispartofthetotaldesignprocess.Theoptimumbeltconveyordesignisdeterminedbystaticorsteadystatedesignmethods.Inthesemethodsthebeltisassumedtobearigid,inelasticbody.Thisenablesquantificationofthesteady-stateoperationofthebeltconveyoranddeterminationofthesizeofconveyorcomponents.Thespecificationofthesteady-stateoperationincludesaquantificationofthesteady-staterunningbelttensionsandpowerconsumptionforallmaterialloadingandrelevantambientconditions.Itshouldberealizedthatfindingtheoptimumdesignisnotaone-timeeffortbutaniterativeprocess6.Designfine-tuning,determinationoftheoptimumstartingandstoppingprocedures,includingdeterminationoftherequiredcontrolalgorithms,anddeterminationofthesettingsandsizesofconveyorcomponentssuchasdrives,brakesandflywheels,aredeterminedbydynamicdesignmethods.Inthesedesignmethods,alsoreferredtoasdynamicanalyses,thebeltisassumedtobeathree-dimensional(visco-)elasticbody.Athreedimensionalwavetheoryshouldbeusedtostudytimedependenttransmissionoflargelocalforceanddisplacementdisturbancesalongthebelt7.Inthistheorythebeltisdividedintoaseriesoffiniteelements.Thefiniteelementsincorporate(visco-)elasticspringsandmasses.Theconstitutivecharacteristicsofthefiniteelementsmustrepresenttherheologicalcharacteristicsofthebelt.Dynamicanalysisproducesthebelttensionandpowerconsumptionduringnon-stationaryoperation,likestartingandstopping,ofthebeltconveyor.Thispaperdiscussesthedesignofhighbelt-speedconveyors,inparticulartheimpactofusinghighbeltspeedsontheperformanceoftheconveyorbeltintermsofenergyconsumptionandsafetyfactorrequirements.Usinghighbeltspeedsalsorequireshighreliabilityofconveyorcomponentssuchasidlerstoachieveanacceptablecomponentlife.Anotherimportantaspectofhigh-speedbeltconveyordesignisthedesignofefficientfeedinganddischargearrangements.Theseaspectswillbediscussedbriefly.Manymethodsofanalyzingabeltsphysicalbehaviorasarheologicalspringhavebeenstudiedandvarioustechniqueshavebeenused.Anappropriatemodelneedstoaddress:1.Elasticmodulusofthebeltlongitudinaltensilemember2.Resistancestomotionwhicharevelocitydependent(i.e.idlers)3.Viscoelasticlossesduetorubber-idlerindentation4.ApparentbeltmoduluschangesduetobeltsagbetweenidlersSincethemathematicsnecessarytosolvethesedynamicproblemsareverycomplex,itisnotthegoalofthispresentationtodetailthetheoreticalbasisofdynamicanalysis.Rather,thepurposeistostressthatasbeltlengthsincreaseandashorizontalcurvesanddistributedpowerbecomesmorecommon,theimportanceofdynamicanalysistakingbeltelasticityintoaccountisvitaltoproperlydevelopcontrolalgorithmsduringbothstoppingandstarting.Usingthe8.5kmconveyorinFigure23asanexample,twosimulationsofstartingwereperformedtocomparecontrolalgorithms.Witha2x1000kWdriveinstalledattheheadend,a2x1000kWdriveatamidpointcarrysidelocationanda1x1000kWdriveatthetail,extremecaremustbetakentoinsurepropercoordinationofalldrivesismaintained.Figure27illustratesa90secondstartwithverypoorcoordinationandsevereoscillationsintorquewithcorrespondingoscillationsinvelocityandbelttensions.TheT1/T2slipratioindicatesdriveslipcouldoccur.Figure28showsthecorrespondingchartsfromarelativelygood180secondstartcoordinatedtosafelyandsmoothlyacceleratetheconveyor.