塑料模具的编制和使用.pdf

THEPREPARATIONANDUSEOFPLASTICMOLDSMBBORISOVUDC66656663032PLASTERMOLDSAREWIDELYUSEDFORCASTINGWARESINTHECERAMICSINDUSTRYAPARTFROMCERTAINADVANTAGES,THEYHAVEALOWMECHANICALSTRENGTHANDSHORTWORKINGLIFEDUETOWEAROFTHEWORKSURFACEUNDERTHEACTIONOFWATERANDELECTROLYTESINTHEBODYBESIDESTHIS,THETEMPERATUREINTHEDRYERCANNOTBEHIGHERTHAN65ASABOVETHISTEMPERATURETHEPLASTERISDESTROYEDTHENECESSITYOFFINDINGASUBSTITUTEFORPLASTERWASINCREASEDWHENTHEPORCELAININDUSTRYBEGANINSTALLINGSEMIAUTOMATICMACHINESFORMOLDINGANDDRYING,WITHINTENSIFIEDDRYINGCONDITIONSTHESEARCHFORASUBSTITUTEFORPLASTERBEGANINOURFACTORYIN1967,ANDTOTHISENDAGROUPWASORGANIZEDCONTAININGTHEFOLLOWINGWORKERSAVSAVELEVA,PSPOLYAKOV,TAPASHKOVA,VAKHOLKIN,AVSARICHEV,FILISOV,ANDOTHERSATTHESTARTOFTHEIRWORKTHERESEARCHGROUPWEREGUIDEDBYDATAFROMTHESTATECERAMICSRESEARCHINSTITUTE1HOWEVER,THISDIDNOTANSWERANUMBEROFQUESTIONSARISINGFROMTHEWORKINGOFTHEPLANT,SUCHASHOWTODESIGNANDMAKEPRESSMOLDSSOASTOAVOIDCRACKINGINTHEPLANEOFINTERSECTIONOFTWOSURFACES,WHATBATCHTOTAKEPERUNITVOLUMEOFMOLD,WHATSCHEDULETOUSEFORTHEHEATTREATMENT,HOWTOOBTAINUNIFORMDISTRIBUTIONOFPORESANDINCREASEGENERALPOROSITY,ANDHOWTOAVOIDADHERINGBYTHEBODY,ETCFOLLOWINGONTHERESULTSOFTHEIRRESEARCH,IN1969THEGROUPBEGANDEVELOPINGTHEPREPARATIONOFPVCMOLDS,ANDCONVERTINGTHEPRODUCTIONLINEOFTHEFACTORYTOTHEIRUSEATTHEPRESENTTIMETHEREAREINTHEFACTORYFIVEPRODUCTIONLINESFORPLATES,THREEOFWHICHAREFORSHALLOW200MMPLATESANDTWOFORDEEP200MMPLATES,ASWELLASSEVENLINESFORCUPSUSINGTHEPLASTICMOLDSATOTALOF24,000PLATESAND3537,000CUPSAREPRODUCEDPERDAY24HTHEPROVISIONALANNUALSAVINGACCRUINGFROMTHEINTRODUCTIONOFONLYONEPRODUCTIONLINEIS2500RUBLESTHEWORKINGLIFEOFTHEPLASTICMOLDSINCUPPRODUCTIONREACHES4000CYCLESANDCANSTILLBEINCREASEDTHELIFEOFTHEMOLDSINPLATEPRODUCTIONHASSTILLNOTBEENDETERMINEDASECTIONFORPREPARINGTHEMOLDSWASORGANIZEDINTHEFACTORYIN1969FIG1THERAWMATERIALWASDOMESTICPOLYVINYLCHLORIDELATEX,GRADEL5,OREMULSIFIEDPOLYVINYLCHLORIDE,GRADEE62POLYVINYLCHLORIDEISTHEPRODUCTOFPOLYMERIZATIONOFVINYLCHLORIDEITISAWHITEFINELYDISPERSEDNORESIDUEONNO0056SIEVEPOWDEROFDENSITY141G/CM3ATATEMPERATUREOF170180ANDUNDERSLIGHTPRESSURESPECIFICPRESSURE005KG/CM2THEPOLYVINYLCHLORIDEPARTICLESMELTANDCOHERETHEFIRSTSTAGEINTHEPREPARATIONOFTHEMOLDSISAPRELIMINARYVIBROMOLDINGONTHEVIBROTABLEWHICHENSURESUNIFORMPOROSITYTHEVIBROTABLEPERFORMS50OSCILLATIONS/SECWITHANAMPLITUDEOF05RAMTHEVIBROMOLDINGISCARRIEDOUTFOR1520SECTHISPRELIMINARYVIBROMOLDINGISANESSENTIALPARTOFTHEPROCESSFORMAKINGTHEMOLDS,SINCE,DURINGMOLDING,INTERNALSTRESSESAREGENERATEDWHICHARECONCENTRATEDNEARTHEPOINTSOFCONTACTOFMOLECULARCOHESIONOFTHEFINEPARTICLESTHISINTERNALSTRESSISESPECIALLYDANGEROUSDURINGTHEPROCESSOFSINTERINGITCANBEREMOVEDBYVIBRATION,WHICHALMOSTCOMPLETELYBREAKSALLCONNECTIONSBETWEENPARTICLESANDENSURESTHEIRUNIFORMDISTRIBUTIONTHEBASICPIECEOFEQUIPMENTINTHEPREPARATIONOFTHEPLASTICMOLDSISTHEMETALPRESSMOLDFIG2WHICHISMADEFROMGRADE45ORST3STEELITSINTERNALSURFACEMUSTBECHROMIUMPLATEDDULEVOPORCELAINFACTORYTRANSLATEDFROMSTEKLOIKERAMIKA,NO3,PP79,MARCH,197291972CONSULTANTSBUREAU,ADIVISIONOFPLENUMPUBLISHINGCORPORATION,227G/EST17THSTREET,NEWYORK,NY10011ALLRIGHTSRESERVEDTHISARTICLECANNOTBEREPRODUCEDFORANYPURPOSEWHATSOEVERWITHOUTPERMISSIONOFTHEPUBLISHERACOPYOFTHISARTICLEISAVAILABLEFROMTHEPUBLISHERFORI500147,13500L23456FIIO987FIGIFIG2FIGIIHANDPRESS2SNOLELECTRICALLYHEATEDCABINETFORHEATTREATMENTOFTHEMOLDS3CABINETFORCOOLINGTHEMOLDS4TABLEFORASSEMBLYANDDISMANTLING5STANDFORPREPAREDMOLDS6STORAGEFORTHEPLASTICS7ELECTRICALLYHEATEDCABINETFORDRYING8STANDFORFINISHINGTHEMOLDS9TABLEFORPACKINGPLASTICSI0TABLEFORMEASURINGOUTPLASTICSIIVIBRATINGTABLEFIG2PRESSMOLDAASSEMBLEDBDISMANTLEDTHEPROCESSOFFILLINGTHEPRESSMOLDFORMAKINGFLATWAREPLATESPLASTICMOLDSISSHOWNINFIG3L5POWDER,WHICHHASPREVIOUSLYBEENDRIEDINTHEELEETRODRYINGCABINETATLL0ANDTHENSCREENEDTHROUGHANO05SIEVE,ISCHARGEDINTOTHEMATRIXOFTHEPRESSMOLDANDLEVELEDWITHASPECIALTOOLTHEAMOUNTOFPLASTICDEPENDSONTHETYPEVOLUMEOFTHEMOLDFORSHALLOW200MMPLATESITIS600G,FORDEEP200MMPLATES660G,FORSAUCERS400G,ANDFORCUPS500515GTHEPRESSMOLDPUNCHISTHENINSERTEDINTOTHEMATRIXINSUCHAWAYTHATITENTERSUNDERITSOWNWEIGHTUNTILITISINCONTACTWITHTHEPLASTICTOCHECKTHECORRECTNESSOFASSEMBLYATTHISPOINT,THEPUNCHISROTATEDRELATIVETOTHEMATRIXTHEASSEMBLEDPRESSMOLDISPLACEDONTHEVIBROTABLEANDCOMPACTEDFOR1520SECAFTERCOMPACTING,THEGAPBETWEENTHEMATRIXFLANGEANDTHEPUNCHFLANGESHOULDBE810RAMTHEPRESSMOLDISNEXTINSERTEDINTOSNOLELECTROCABINETFORTHEHEATPROCESSANDAWEIGHTISPLACEDONTHETOPSOASTOGIVEAPRESSUREOF005KG/CM2TOMONITORTHETEMPERATURE,ATHERMOMETERISINSERTEDSOTHATITTOUCHESTHECENTEROFTHEPUNCHASMALLAMOUNTOFTHEPLASTICISHEAPEDONTHEPUNCHFLANGE,ANDITSCHANGEINCOLORISUSEDTOASSESSTHEREADINESSOFTHEMOLDTHEHEATPROCESSCONTINUESFOR23HANDATITSCOMPLETIONTHETEMPERATUREOFTHEPRESSMOLDIS170175AFTERTHECOMPLETIONOFTHEHEATPROCESS,THETHERMOMETERISREMOVEDANDTHEPRESSMOLDTAKENFROMTHECABINETANDPLACEDINTOTHEVENTILATEDCABINETTOCOOLTHEPRESSMOLDISTHENDISMANTLEDUSINGANEXTRACTIONSCREWTHEPREPAREDPLASTICMOLDISREMOVED,TRIMMEDSMOOTHATTHEEDGES,ANDAFTERINSPECTIONISREADYFORUSETHEMOLDSFORTHEHOLLOWWARESCUPSWEREPREPAREDACCORDINGTOTHEFOLLOWINGSCHEDULET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