Tom qab cov hlau molten yog txhaj rau hauv pwm kab noj hniav, ib lub plhaub nyias ua ntej ua rau ntawm phab ntsa kab noj hniav. Thaum lub plhaub no yog compressed los ntawm cov khoom molten tom ntej thaum lub sij hawm txhaws, nws tuaj yeem ua rau tawg tawg.
Thaum lub plhaub nyias no raug torn lossis hloov, khawb lossis wrinkles tshwm rau ntawm qhov chaw ntawm cov yas. Piv txwv li, nyob rau hauv qis-qhov ntom polyethylene qhov chaw nrog qhov ntsuas qis qis, hloov lub teeb thiab cov kab txaij tsaus nti feem ntau pom ntawm qhov chaw. Cov cheeb tsam no feem ntau nyob ib ncig ntawm lub rooj vag thiab npog tag nrho saum npoo. Nyias-cov phab ntsa yog qhov tshwj xeeb tshaj yog rau hom kev tsis xws luag, feem ntau vim tias cov khoom siv molten raug rau lub siab tseem ceeb ua ntej cov kab noj hniav me me tau puv tag, ua rau cov pob txha tawg thiab qhov tsis xws luag.
Feem ntau, qeeb qeeb ntawm qhov txias ntawm cov hlau molten thaum lub sij hawm ntim cov txheej txheem thiab tus nqi ntawm lub plhaub tsim yog txoj hauv kev zoo tshaj plaws los tshem tawm yam tsis xws luag. Qhov no tuaj yeem ua tiav los ntawm qhov tsim nyog nce pwm kub lossis nce qhov kub hauv zos ntawm qhov chaw tawg tawg. Cov cua sov hauv zos ntawm cov pwm kab noj hniav tuaj yeem ua tiav siv cov tubular hluav taws xob me me tso rau ntawm lub rooj vag thiab ntawm qhov chaw tawg tawg.
Tsis tu ncua pulsating ntws ntawm molten khoom tshwm sim nyob rau hauv lub pwm kab noj hniav.
Cov yam ntxwv ntws ntawm cov khoom molten muaj feem xyuam rau nws cov khoom rheological thiab lub rooj vag hla -sectional cheeb tsam, uas txiav txim siab tus nqi ntawm cov khoom molten ntawm cov pwm inlet. Thaum lub rooj vag loj me me thiab qhov kev txhaj tshuaj yog siab, cov khoom molten yog txhaj rau hauv kab noj hniav raws li nyias nyias, tortuous dav hlau. Yog hais tias cov khoom molten txias sai heev, nws yuav tsis fuse zoo nrog cov tom ntej irregular flow, uas ua rau nto cloudiness thiab streaks nyob ze ntawm lub rooj vag. Qee lub sij hawm, cov khoom txias me me tuaj yeem txav mus raws cov kab noj hniav ntawm cov pwm, ua rau saum npoo av thiab streaks tshwm sim ntawm qhov chaw deb ntawm lub rooj vag.
Feem ntau, nto cloudiness thiab streaks generated thaum lub sij hawm txhaj tshuaj ntawm crystalline polymers yog nyuaj rau tshem tawm vim hais tias cov resins muaj kuj kub melting kub. Piv nrog rau amorphous polymers, crystalline polymers kho sai dua, muaj qhov nqaim ua haujlwm kub ntau, thiab qhov tsis sib xws ntawm cov khoom molten generated ntawm cov ntsiab lus ntawm cov phab ntsa tuab hloov sai thiab cov kev hloov pauv tam sim no muaj lub sij hawm luv luv rau fuse nrog cov khoom seem hauv cov kab noj hniav, yooj yim ua rau saum npoo av thiab streaks.
Txhawm rau daws cov teeb meem no, nyob rau hauv cov nqe lus ntawm kev ua haujlwm, qhov kub ntawm pwm, chim, thiab lub nozzle yuav tsum tau nce kom tsim nyog, thaum lub hau ntswj ceev ceev thaum txhaj tshuaj yuav tsum raug txo.
Hais txog kev ua haujlwm pwm, lub rooj vag loj yuav tsum tau nthuav dav, nrog lub kiv cua - zoo li lub rooj vag yog nyiam. Yog tias siv lub qhov taub - hom rooj vag, nws qhov loj me me dhau lawm yuav ua rau cov khoom seem thiab impurities ntawm lub rooj vag cuam tshuam rau pwm filling, exacerbating irregular cov ntaub ntawv; nws qhov loj me yuav tsum tau nce kom tsim nyog. Cov pwm venting tsis zoo yuav cuam tshuam rau cov khoom ntws tsis tu ncua thiab yuav tsum tau txhim kho.
Tsis tas li ntawd, cov roj nplua nyeem siv yuav tsum raug txo kom tsawg, thiab yuav tsum xaiv hom tsim nyog.
