Uyini umehluko phakathi komshini wokubumba umjovo we-PET preform kanye nomshini wokubumba umjovo ojwayelekile?

Uchwepheshe Umshini wokubumba umjovo we-PET preform ihluke kakhulu emshinini wokubumba umjovo ojwayelekile wenhloso ejwayelekile, njengoba yakhiwe ngendlela ehlukile ukuze ivumelane nezakhiwo ezikhethekile zomzimba namakhemikhali e-PET resin, imishini evamile engakwazi ukukwamukela ngokugcwele. Impahla ye-PET ifaka ukumuncwa okuphezulu komswakama, ukuwohloka kokushisa okuzwelayo, i-viscosity encibilikayo ephansi, kanye nezidingo eziqinile zokufana kwe-plasticization kanye nesivinini sokubumba, konke okudinga ukucushwa kwemishini okukhethekile. Okokuqala nokubalulekile, uhlelo lwe-plasticizing luhluke ngokuphelele. Imishini ye-PET preform ifakwe isikulufu esizinikezele se-low-shear kanye nomgqomo onesilinganiso sobude ukuya kobubanzi 24:1 ku 26:1, enezikulufo ezingashoni futhi azikho idizayini ye-dead-angle. Lesi sakhiwo sigwema amandla amaningi okugunda okubangela ukuphuka kweketango lamangqamuzana e-PET, ngempumelelo ukuvimbela ukuncibilika yellowing, i-carbonization, kanye nokwehliswa kokungafihli ngesikhathi sokucubungula izinga lokushisa eliphezulu. Ngokungqubuzanayo, izikulufo zomshini womjovo ezijwayelekile zenzelwe amapulasitiki asemhlabeni wonke njenge-PP ne-ABS, ikhiqiza ukushisa kwe-shear okwedlulele okonakalisa kalula izinto ze-PET futhi kukhiqize ama-preform anesici anemicu ephuzi kanye nenkungu.. Okwesibili, uhlelo lokulawula izinga lokushisa Imishini ye-PET preform isekela ukulawulwa kwezinga lokushisa okungaguquki kwe-PID enezigaba eziningi, evala umgqomo, umlomo wombhobho, kanye ne-adaptha yesikhunta enephutha lokushisa elilawulwa ngaphakathi ±1°C. Njengoba izinga lokushisa lokucubungula i-PET lisukela ku-260°C kuya ku-285°C, ngisho nokushisa okuncane kwendawo kuzodala ukwanda kwe-acetaldehyde nokuguga kwezinto ezibonakalayo, inkinga imishini evamile enokulawula ukushisa okungenamandla ayikwazi ukuyigwema. Ngaphezu kwalokho, Ukukhiqizwa kwe-PET preform kudinga ukugcwaliswa kodonga oluncane olunesivinini esikhulu kanye nokugoqa okuqinile ukuze kuqinisekiswe ukukhiya isikhunta esifanayo nokuvikela ukukhanya kuma-multi-cavity preforms.. Imishini ye-preform yobungcweti isebenzisa izifanekiso eziqinile eziqinile kanye nezinhlelo zokujova ezisheshayo eziphendula ngokushesha, ukuzuza ukugcwaliswa okuzinzile kwesivinini esiphezulu ngaphakathi 0.1 imizuzwana, kuyilapho imishini evamile inokusabela okunensayo komjovo kanye nokuqina kokugoqa okunganele, okuholela ekuqineni kodonga lwe-preform engalingani kanye nesivuno esincane. Ngokwengeziwe, imishini ye-PET ezinikele yenzelwe isikhathi esifushane sokuhlala, namashaneli okugeleza ahlelekile kanye nezakhiwo ze-nozzle ezilwa nokuma ukuze kuncishiswe ukuncibilika nokonakala. Baphinde bagcine izindawo zokuhlangana ezichwepheshile zokusekela okokusebenza okufana nokomisa umswakama kanye nama-chiller asezimbonini, ukwakha uhlelo oluphelele lokukhiqiza lokubumba i-PET. Imishini yokujova ejwayelekile ayinakho lokhu kulungiselelwa okuqondisiwe, okuholela ekusebenzeni kahle kokukhiqiza, amazinga anesici aphezulu, kanye nokungakwazi ukuhlangabezana namazinga okukhiqizwa kwe-preform yebanga lokudla. Ngokufigqiwe, imishini ejwayelekile yomjovo ingaqedela ukubumba okulula kwepulasitiki, kuyilapho imishini ye-PET preform yobungcweti igxile ekukhanyeni okuphezulu, i-acetaldehyde ephansi, isivuno esiphezulu, kanye nokukhiqizwa kwenani elikhulu ngesivinini esikhulu, ehambisana ngokugcwele nezidingo zenqubo eqinile ye Ukukhiqizwa kwe-PET preform.