Ukuqondwa kweenkcazo ezibonakalayo ezichazwe kwesi sahluko kuphela kunokungqina ukuba luncedo ngokwaneleyo kubafundi abaninzi, kwaye kubanceda baphucule iinkqubo zabo kunye neemveliso.I-polymer extruder isetyenziselwa ukunyibilikisa i-polymer eyomeleleyo kwaye ihambise ipolymer etyhidiweyo kwiinkqubo ezahlukeneyo zokubumba okanye zokubunjwa.I-screw kuphela kwecandelo elisebenzayo le-extruder.Onke amanye amacandelo (motor, gear-box, hopper, barrel and die, etc.) abonelela nje ngenkxaso eyimfuneko ukuze isikrufu sisebenze kakuhle.Iyonke imisebenzi ye-extruder iboniswe ngezantsi.
Umsebenzi wokutyisa wokudlulisa i-polymer yokutya ukusuka kwi-hopper ukuya kwi-screw channel yenzeke ngaphandle kwe-screw, kwaye ngokuyimfuneko ayixhomekekanga kuyilo lwe-screw.Isikrufu senza imisebenzi emithathu esisiseko: (1) umsebenzi ogqithisayo oqinileyo, (2) umsebenzi wokunyibilikisa, kunye (3) nomsebenzi wokulinganisa okanye wokumpompa.Imisebenzi emithathu yezikrufu yenzeka ngaxeshanye kuninzi lobude besikrufu kwaye ixhomekeke enye ngokumandla.Igama lejometri yecandelo lesikrufu njengecandelo lokutyisa, eliboniswe kwiSahluko 1;Umzobo 1.3, awubonisi kuphela umsebenzi wecandelo le-screw.Ngokomzekelo, icandelo lokutya alenzi kuphela umsebenzi oqinileyo wokuhambisa, kodwa kunye nokunyibilika kunye nemisebenzi yokulinganisa.Isikrufu sisenza neminye imisebenzi yesibini enje ngokuxutywa kokusasaza, ukuxuba okusasazeka, kunye nokusulungekiswa kwe-chear okanye i-homogenization.Ukuxuba ukusabalalisa kubhekiselele ekuhlengahlengisweni kwe-spacial yamacandelo ahlukeneyo, kwaye ukuxutywa kwe-dispersive kubhekisela ekunciphiseni ubukhulu becandelo njengoko kuchazwe kwiSahluko 2;Icandelo 2.6.4.Ukusulungekiswa kwe-shear kubhekiselele kwi-homogenization yeemolekyuli zepolymer ngokucheba.I-extruder ye-screw eyodwa yimpompo yevolumetric eqhubekayo ngaphandle kokukwazi ukuxuba umva kwaye ngaphandle kokukwazi ukuhambisa okulungileyo.Yintoni engena kwisikrufu kuqala, iphuma kwisikrufu kuqala.Ipolymer, njengento eqinileyo okanye enyibilikayo, yehla ijelo le-screw ngemikhosi eyenziwa kwipolymer ngesikrufu esijikelezayo kunye nomphanda omileyo.Akukho ndlela yokuhambisa ngokuqinisekileyo ipolima ecaleni kwejelo lokujija ukuya kwidayiti.Isikrufu esijikelezayo sibamba ipholima kwaye sizama ukujikelezisa ipolima ngaso.Masithi i-barrel isusiwe kwi-extruder, okanye i-lubricated ngokugqibeleleyo, kangangokuthi inika ukuchasana nokunyakaza kwepolymer.Emva koko i-polymer ijikeleza nje nge-screw ngesantya esifanayo kwaye akukho nto iphuma kwi-screw.Umgqomo omileyo unika amandla okuqhawula kwipolymer ejikelezayo kwaye yenza ukuba i-polymer ityibilike kancinane kwi-screw surface.I-polymer isajikeleza nge-screw rubbing kumphezulu we-barrel, kodwa ngesantya esisezantsi kancinci kune-screw, ngenxa yokutyibilika.Ukutyibilika kwepolymer kumphezulu wesikrufu ecaleni kwesijija setshaneli kubangela umyinge wokuphuma.Umphezulu we-screw surface unyusa izinga lokuphuma, kodwa umphezulu we-barrel ethambisayo wehlisa isantya semveliso ngokuyingozi.Kuyaqondakala ngokucacileyo ukuba kutheni i-screws zorhwebo ziphuculwe kakhulu, kwaye kutheni imibhobho ye-grooved kwicandelo lokutya ikhethwayo.Nangona izenzo ezininzi zorhwebo zaphuhliswa ngokwamandla kunokuba zisekelwe kuhlalutyo lwethiyori, ngokuqinisekileyo ziyavumelana neengcamango zethiyori ezisisiseko.Iindlela ezingaphakathi kwe-screw extruder enye ziphononongwa ngokuphonononga i-polymer cross-sections ecaleni kwe-screw channel ethathwe "kwi-screw-frizing experiments".Kuvavanyo lokukhenkceza ngezikrufu oluqaliswe nguMaddock [1], isikrufu siqhutywa ukuphumeza umsebenzi ozinzileyo.Emva koko, i-screw iyamiswa kwaye ukupholisa kwamanzi kusetyenziswa kwi-barrel (kunye nakwi-screw ukuba kunokwenzeka) ukukhenkcela i-polymer ngaphakathi kwe-screw channel.Umgqomo ushushu kwakhona ukuze unyibilike i-polymer, kwaye isikrufu sityhalwa ngaphandle komgqomo njengoko i-polymer iqala ukunyibilika kumphezulu wombhobho.Emva koko, umcu wepolymer oqinisiweyo uyasuswa kwitshaneli ye-screw kwaye usikwe kwiindawo ezininzi ukuphonononga amacandelo anqamlezayo ecaleni kwetshaneli yesikrufu.Ezinye iipellet ezinemibala zixutywe kwisondlo ukuze zibone indlela yokunyibilika kunye nepateni yokuhamba.Iipellets ezinemibala zigcina iimilo zazo ukuba zithe zahlala ziqinile ngaphakathi kwebhedi eqinileyo phambi kokuba isikrufu siyeke, kodwa ziye zasheka kwaye zibe yimichilo ngaphakathi kwidama lokunyibilika ukuba bezinyibilikile phambi kokuba isikrufu siyeke.
Ixesha lokuposa: Jun-16-2019