I-Plastic Extrusion Screw Design kanye nezinhlobo zenqubo yokukhipha

I-Plastics extrusion iyinqubo yokukhiqiza ivolumu ephezulu lapho ipulasitiki eluhlaza incibilikiswa khona bese yenziwa iphrofayili eqhubekayo.I-Extrusion ikhiqiza izinto ezinjengamapayipi/amashubhu, i-weatherstripping, uthango, ama-railing edekhi, amafreyimu amafasitela, amafilimu epulasitiki namashidi, ama-thermoplastic coatings, kanye nokufakwa kwezintambo.

Idizayini yesikulufu:

Idizayini yesikulufu ibalulekile ekucubunguleni ipulasitiki.Ikakhulukazi inemisebenzi emithathu ehlukene: okungukuthi, indlela yokudla;ukuncibilika okufanayo kanye nokuxutshwa kwepulasitiki futhi ekugcineni kukhiqiza ingcindezi yokusunduza into encibilikisiwe ngokufa.Ubude besikulufa (L) bubhekiselwa kububanzi baso (D) njengesilinganiso se-L/D.Ngokuvamile, isilinganiso se-L/D sisetshenziswa njengo-24:1, kodwa ngokuxuba okwengeziwe nokukhiphayo, singase sikhuphuke sifike ku-32:1.Kunezindawo ezintathu ezingaba khona kubude obuyisikulufu okungukuthi indawo yokuphakelayo, indawo yokuncibilika, nendawo yokukala.(a) Indawo yokuphakelayo: Kule ndawo, i-resin ishuthekwa isuka ku-hopper ingene emgqonyeni, futhi ukujula kwesiteshi akushintshi.(b) Indawo encibilikayo: Izinto zepulasitiki ziyancibilika futhi ukujula kwesiteshi kuba kuncane kancane kancane.Ibuye ibizwe ngokuthi indawo yoguquko noma yokuminyanisa.(c) Indawo yokukala: Ipulasitiki encibilikisiwe ixutshwa ezingeni lokushisa elifanayo kanye nokucindezela bese idluliswa ngedayidi.Ukujula kwesiteshi kuhlala njalo kuyo yonke le ndawo.

Izinhlobo ze-Extrusion Process

Inqubo ye-extrusion ihlukaniswa kabanzi yaba izinhlobo eziyisikhombisa ezihlukene kuye ngezinhlelo zokusebenza ezithile.(a)Ukukhishwa Kweshidi/IfilimuKule nqubo ye-extrusion, izinto zepulasitiki ezincibilikisiwe zikhishwa ngefa eliyisicaba.Amaroli okupholisa asetshenziselwa ukunquma ukujiya kweshidi/ifilimu nokuthungwa kwalo kwendawo.Ubukhulu beshidi bungatholakala ku-0.2 kuya ku-15 mm.Ishidi elincane eliyisicaba noma ifilimu yezinto zepulasitiki zingenziwa.Ngokuvamile, ipulasitiki ye-polystyrene isetshenziswa njengento eluhlaza kunqubo ye-extrusion yeshidi.(b)I-Blown Film ExtrusionEnqubweni yefilimu eshaywayo, ukufa kufana nesilinda esime mpo esinephrofayili eyindilinga.Ipulasitiki encibilikisiwe idonswa phezulu kusuka efashini ngama-nip rollers.Umoya ocindezelweyo usetshenziselwa ukufutha ishubhu.Eceleni kwefasi, kufakwa indandatho yomoya.Inhloso ye-air-ring ukupholisa ifilimu njengoba ihambela phezulu.Phakathi nendawo yokufa, kukhona i-air inlet lapho umoya ocindezelwe ungaphoqelelwa phakathi nendawo yephrofayili eyindilinga, futhi udale ibhamuza.Ingxenye yesiphambano esiyindilinga ekhishiwe ingandiswa izikhathi ezingama-2-3 zobubanzi bokufa.Amabhamuza ayagoqwa ngosizo lwepuleti eligoqayo.Ama-nip rolls acaba ibhamuza libe ungqimba oluphindwe kabili lwefilimu ebizwa ngokuthi i-layflat.Ubukhulu bodonga lwefilimu bungalawulwa ngokushintsha ijubane lama-nip rollers.I-layflat ingaxutshwa ngendlela ye-roll noma isikwe ibe yizimo ezifunwayo.Uhlangothi olungezansi lwe-layflat luvalwe ngokufakwa kokushisa, futhi lunqamule luye phezulu ukuze luvuleke;ngakho-ke ingasetshenziswa ukwenza isikhwama sepulasitiki.Ububanzi bokufa bungase buhluke ku-1 kuya ku-300 amasentimitha. Ngokuvamile, ipulasitiki ye-polyurethane isetshenziswa kule nqubo.

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(c)Ngaphezulu kwe-Jacketing Extrusion

Lokhu kubizwa nangokuthi inqubo yokuhlanganisa ucingo.Kule nqubo, ucingo olungenalutho ludonswa phakathi nendawo yokufa.Kunezinhlobo ezimbili ezihlukene zamathuluzi e-extrusion asetshenziselwa ukumboza phezu kwe-wire iepressure noma i-jacketing tooling.Uma ukuxhumana okusondelene noma ukunamathela kuyadingeka phakathi kocingo nokunamathela, kusetshenziswa ithuluzi lokucindezela.Uma ukunamathela kungafunwa, i-jacketing tooling isetshenziswa.Ukuze kusetshenziswe ingcindezi, ucingo luhlehliswa ngaphakathi kwefasi, lapho luhlangana khona nepulasitiki encibilikisiwe ngengcindezi ephezulu kakhulu.Ukuze kusetshenziswe amajakhethi, intambo izonwebeka futhi ipulasitiki encibilikisiwe izokwenza ikhava ocingweni ngemva kokufa.Intambo engenalutho idliswa ngedayizi futhi ayihlangani ngqo nepulasitiki encibilikisiwe ize ishiye idayisi.Umehluko omkhulu phakathi kwe-jacketing kanye ne-pressure tooling yindawo yocingo ngokuphathelene nokufa.

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(d)I-Tubing ExtrusionKule nqubo, ipulasitiki elincibilikisiwe is extruded ngokusebenzisa die futhi eziyize cross izingxenye akhiwa ngokubeka mandrel ngaphakathi die.Ishubhu elinezimbobo eziningi lingase lenzelwe izinhlelo zokusebenza ezithile, ngokubeka inani lama-mandrel phakathi nendawo yokufa.(e)I-CoextrusionI-Coextrusion inqubo yokukhipha yokwenza izingqimba eziningi zezinto ngesikhathi esisodwa.Isetshenziselwa ukusebenzisa isendlalelo esisodwa noma ngaphezulu phezu kwesisekelo sezinto ukuze kutholwe izici ezithile ezifana nokumunca i-ultraviolet, ukubamba, ingaphezulu le-matte, nokuboniswa kwamandla, kuyilapho impahla eyisisekelo ifaneleka kakhulu kwezinye izinhlelo zokusebenza, isb ukumelana nomthelela nokusebenza kwesakhiwo.Ingase isetshenziswe kunoma yiziphi izinqubo ezifana nefilimu ephephethwayo, ukweqa ijakhethi, ishubhu, ukukhishwa kweshidi/ifilimu.Kule nqubo, ama-extruder amabili noma ngaphezulu asetshenziselwa ukuletha izinto ezihlanganiswa zibe ifa elilodwa elikhipha izinto ezisesimweni esifiselekayo.Ugqinsi lwesendlalelo kulawulwa isivinini nosayizi wama-extruder angawodwana aletha izinto.(f)I-Extrusion CoatingI-Extrusion coating isetshenziselwa ukwenza isendlalelo esengeziwe phezu kwe-rollstock ekhona yephepha, i-foil noma ifilimu.Isibonelo, ukuthuthukisa ukumelana kwamanzi kwephepha le-polyethylene enamathela kusetshenziswa.Izicelo ze-extrusion coating ziyi-liquid package, iphepha lezithombe, izimvilophu, amasaka amasaka okufaka umanyolo kanye nokupakishwa kwezokwelapha.Ngokuvamile, i-polyethylene ne-polypropylene isetshenziswa.