Yog tias koj nyob hauv PET preform manufacturing lag luam, koj paub zoo dua lwm tus neeg tias qhov zoo ntawm preforms los ntawm koj cov kab ntau lawm tsis yog hais txog PET preform pwm nws tus kheej. Nws yog ib qho tseem ceeb ntawm cov khoom sib txuas, pib los ntawm cov khoom nyoos pellets pov tseg rau hauv lub hopper tag nrho txoj hauv kev mus rau qhov kawg qhov kev kuaj xyuas ua ntej lub taub hau preforms mus rau lub tshuab molder, thiab txhua txhua kauj ruam nyob rau hauv nruab nrab ntawm yuav ua tau los yog tawg seb koj preforms zoo meej, los yog xaus li seem. Peb tau tsim thiab tsim siab -precision PET preform pwm tau ze li ntawm 20 xyoo, thiab peb tau pom txhua qhov yuam kev, txhua qhov luv luv uas ua rau tsis zoo preforms, thiab txhua qhov tweak me me uas hloov cov kab teeb meem mus rau qhov siab - zoo, siab - ntim ua haujlwm. Yog li hnub no, kuv yuav taug kev koj los ntawm cov ntsiab lus tseem ceeb uas tseem ceeb heev thaum nws los ua rau saum -notch PET preforms, ncaj nraim los ntawm peb qhov kev xav raws li cov neeg uas tsim thiab tsim cov pwm uas tsim cov khoom no txhua hnub.
Ua ntej tshaj, cov khoom siv raw. Koj tuaj yeem muaj cov pwm pwm zoo tshaj plaws hauv ntiaj teb, tab sis yog tias koj pub mis rau PET tsis zoo, koj yuav tsis ua qhov zoo preform. Peb tau suav tsis txheeb cov neeg siv khoom tuaj rau peb yws txog qhov tsis zoo ntawm preform zoo, tsuas yog kom paub qhov laj thawj yog lub raj mis - qib PET chips lawv siv. Qhov loj tshaj plaws ntawm no yog yuav ua li cas cov resin tau ua tiav thaum lub sij hawm cov khoom siv - xeev polycondensation, los yog SSP luv luv. Peb tau khiav ntau qhov kev sim nrog plaub qhov kev lag luam sib txawv SSP- ua tiav PET resins, thiab qhov sib txawv ntawm qhov kawg preform zoo yog hmo ntuj thiab nruab hnub. Lub sij hawm SSP nyob ntev dua thiab cov tshuaj tiv thaiv kub siab dua tsis yog hloov cov resin intrinsic viscosity (IV) -lawv cuam tshuam ncaj qha rau crystallinity, xim, kub hnyiab, thiab txawm tias cov theem ntawm cov khoom tsis zoo xws li acetaldehyde (AA) thiab 2-methyl-1,3-dioxolane kawg (M. Yog tias koj cov resin muaj cov ntsiab lus AA siab, koj yuav xaus nrog cov preforms uas tsis muaj ntxhiab, uas yog kev tuag rau kev ntim khoom noj thiab dej haus.
Thiab yog tias IV qis dhau lawm? Koj cov preforms yuav tsis muaj lub zog txhua yam uas lawv xav tau kom muaj sia nyob tshuab molding, cia nyob ib leeg kom sau thiab xa khoom. Koj kuj yuav tsum tau saib xyuas rau cov oligomers ntau dhau ntawm cov cob- ntau dhau ntawm cov no yuav ua rau muaj qhov tsis xws luag ntawm koj cov preforms, thiab tuaj yeem tsim nyob rau hauv koj cov kab noj hniav hauv lub sijhawm, ua rau muaj teeb meem ntau ntxiv hauv kab. Thiab tsis txhob ua rau kuv pib ntawm resin ziab. Yog li ntau tus neeg muas zaub hla kev ziab kom zoo, lossis siv lub tshuab ziab khaub ncaws pheej yig uas tsis tuaj yeem tswj xyuas qhov kub thiab txias, thiab tom qab ntawd xav tias vim li cas lawv cov preforms puv puv npuas, nyiaj streaks, los yog voids. Rau peb, thawj qhov uas peb xyuas thaum tus neeg siv khoom muaj teeb meem zoo preform yog cov resin - yog tias tsis yog, tsis muaj dab tsi ntxiv uas peb ua nrog pwm yuav kho qhov teeb meem.
Tom ntej no, lub plawv ntawm tag nrho cov kev ua haujlwm: pwm tsim thiab kev tsim khoom. Qhov no yog peb qhob cij thiab butter, thiab peb tuaj yeem qhia rau koj yam tsis muaj duab ntxoov ntxoo ntawm qhov tsis ntseeg tias qhov zoo ntawm koj cov pwm yog qhov tseem ceeb tshaj plaws hauv kev txiav txim siab qhov zoo ntawm koj cov preforms. Cia peb pib nrog lub hauv paus: kab noj hniav sib xws. Rau siab - ntim ntau lawm, koj tab tom khiav 48, 96, lossis ntau kab noj hniav hauv ib lub pwm, thiab txhua qhov ntawm cov kab noj hniav yuav tsum zoo ib yam nkaus. Peb tab tom tham kam rau siab mus rau micron ntawm no. Yog tias muaj qhov sib txawv me ntsis hauv qhov chaw txias txias, qhov rooj loj, lossis kab noj hniav geometry ntawm ob kab noj hniav, koj yuav tau txais preforms uas muaj qhov sib txawv, qhov sib txawv ntawm phab ntsa thicknesses, thiab wildly sib txawv qib zoo. Peb tau muaj cov neeg muas zaub tuaj rau peb nrog pwm los ntawm lwm lub khw uas cov kab noj hniav sib txawv ntawm qhov hnyav tshaj 0.5 grams, thiab lawv tsis tuaj yeem paub tias yog vim li cas lawv lub tshuab moulding tsis lees paub yog los ntawm lub ru tsev. Rau peb, txhua lub pwm uas peb tsim los ntawm cov kab noj hniav nruj heev-mus rau-kab noj hniav kuaj xyuas, siv lub siab-CMM cov cav tov kom ntseeg tau tias txhua qhov ntev yog tuag rau, txhua txhua lub sijhawm.
Tom qab ntawd muaj qhov txias system tsim. Qhov no yog qhov feem ntau underrated ntawm preform pwm tsim, thiab nws yog qhov twg 90% ntawm cov pwm -txog preform defects los ntawm. Cov pwm yuav tsum muaj qhov txias txias thoob plaws txhua qhov kab noj hniav, nrog cov cua txias tso kom ze rau ntawm cov kab noj hniav raws li qhov ua tau, yam tsis muaj kev cuam tshuam cov pwm cov qauv kev ncaj ncees. Yog tias ib feem ntawm cov pwm kub kub dua li lwm qhov, qhov preform yuav txias tsis sib xws, ua rau muaj kev kub ntxhov, kev ntxhov siab sab hauv, thiab txawm tawg thaum lub tshuab molding. Peb tsim peb cov pwm nrog optimized txias channel layouts, siv computational fluid dynamics (CFD) simulations los xyuas kom meej lub coolant ntws txawm nyob rau hauv txhua txhua kab noj hniav, tsis muaj qhov kub thiab txias zones. Peb kuj tsim cov dej txias txias tshwj xeeb los ua haujlwm nrog pwm dehumidifiers, uas tiv thaiv kom tsis txhob muaj qhov sib txuam ntawm cov pwm. Condensation yog ib qho teeb meem loj nyob rau hauv preform ntau lawm- nws ua rau cov dej cim ntawm lub preform nto, thiab tuaj yeem ua rau pwm corrosion nyob rau lub sij hawm, ua rau koj cov pwm kim.
Lwm qhov tseem ceeb ntawm cov pwm yog qhov ejection system. Peb tau siv ntau xyoo los ua kom tiav peb cov txheej txheem pwm preform ejection, vim tias qhov kev tshem tawm tsis zoo yuav ua rau qhov zoo tshaj plaws - tsim kab noj hniav. Koj xav tau lub zog ejection txaus los thawb lub preform tawm ntawm cov kab noj hniav yam tsis muaj kev puas tsuaj, tab sis tsis yog ntau heev uas koj ua rau ejector tus pin qhab nia, "sab saum toj dawb" tsis xws luag, los yog tawg lub preform. Peb tsim peb lub tshuab ejection nrog tus naj npawb tseeb, txoj kab uas hla, thiab qhov chaw ntawm ejector pins kom phim lub preform geometry, kom ntseeg tau tias txawm quab yuam faib thoob plaws tag nrho cov preform thaum lub sij hawm ejection. Peb kuj ua hauj lwm nrog peb cov neeg muas zaub kom phim lub ejection system rau lawv lub tshuab txhaj tshuaj lub peev xwm, vim hais tias txawm qhov zoo tshaj plaws ejection system yuav tsis ua hauj lwm yog hais tias lub tshuab ejector stroke los yog quab yuam tsis mus txog par.
Tom qab ntawd muaj lub rooj vag thiab kub khiav system. Rau siab -kev ceev preform ntau lawm, ib tug zoo- tsim kub khiav system tsis yog -negotiable. Lub rooj vag loj, cov duab, thiab qhov chaw yuav tsum tau ua kom zoo sib xws rau cov qauv tsim thiab cov khoom siv. Yog tias lub qhov rooj me me dhau lawm, koj yuav tau txais cov cua sov ntau dhau, ua rau cov resin degradation thiab siab AA cov ntsiab lus. Yog tias nws loj dhau lawm, koj yuav tau txais lub rooj vag vestige tsis xws luag, lossis txawm tias txoj hlua ntawm kev txhaj tshuaj. Peb tsim peb lub tshuab khiav kub nrog kev tswj xyuas qhov kub thiab txias rau txhua cheeb tsam, kom cov resin nyob ntawm qhov kub thiab txias ntawm lub tshuab nozzle tag nrho txoj kev mus rau lub qhov rooj kab noj hniav, tshem tawm cov chaw tuag uas cov resin tuaj yeem degrade thiab ua rau cov pob dub los yog cov xim tsis zoo hauv cov preforms.
Txawm hais tias koj muaj lub zoo meej resin thiab cov pwm zoo meej, koj tseem yuav ua phem preforms yog tias koj cov cuab yeej tsis ua haujlwm. Peb tau pom lub sijhawm no thiab ib zaug ntxiv -cov neeg siv khoom yuav peb cov pwm siab -precision pwm, muab tso rau ntawm tus nqi pheej yig, dav dav- lub hom phiaj txhaj tshuaj, thiab xav paub tias vim li cas lawv tsis tuaj yeem tau txais cov khoom zoo sib xws. Lub tshuab txhaj tshuaj txheem tsuas yog yuav tsis txiav nws rau siab - ntim, siab - zoo PET preform ntau lawm. Koj xav tau lub tshuab uas yog lub hom phiaj- ua rau PET, nrog lub siab- qhov kev txhaj tshuaj zoo, lub tshuab clamp ruaj khov, thiab lub tshuab yas tsim tshwj xeeb rau PET resin.
Cia peb pib nrog cov ntsia hlau. Peb ib txwm xav kom peb cov neeg siv khoom siv PET- tshwj xeeb ntsia hlau tsim, nrog rau qhov ntev 25: 1 - mus rau - txoj kab uas hla, zoo li cov uas peb tau pab tsim rau peb cov koom tes tshuab manufacturers. PET ntsia hlau zoo yuav tsum tau yaj cov resin sib npaug, tsis tshaj - shearing nws, vim tias dhau - shearing ua rau thermal degradation, uas coj peb rov qab mus rau qhov teeb meem AA uas peb tau tham dhau los. Cov ntsia hlau tseem yuav tsum muaj tus nqi plasticization siab txaus kom ua raws li lub sijhawm voj voog - yog tias koj cov ntsia hlau tsis tuaj yeem yaj cov resin sai txaus, koj yuav tau tos ib ncig ntawm cov khoom kom yaj, uas tua koj cov khoom tsim tau, tab sis qhov tseem ceeb tshaj, nws tuaj yeem ua rau qhov kub tsis sib xws, uas txhais tau hais tias tsis muaj qhov zoo ntawm preform. Peb kuj ib txwm thawb peb cov neeg siv khoom siv tshuab nrog hluav taws xob ua ntej -plasticization thiab synchronous melting technology. Nws tso cai rau koj khiav cov pwm qhib thiab yaj ua haujlwm tib lub sijhawm, txiav 3 mus rau 4 vib nas this ntawm koj lub sijhawm voj voog, tab sis qhov tseem ceeb tshaj, nws khaws cov yaj hauv lub thoob rau ntau lub sijhawm, yog li txhua qhov txhaj tshuaj yog tib yam.
Tom qab ntawd muaj lub clamp unit thiab ejection system. Rau PET preform pwm, koj xav tau lub tshuab nrog txaus clamp quab yuam los tuav cov pwm kaw tawm tsam qhov kev txhaj tshuaj siab siv hauv kev tsim ua ntej, tab sis koj kuj xav tau cov txheej txheem ejection uas tau tsim tshwj xeeb rau preform pwm. Peb ib txwm ua haujlwm nrog peb cov neeg siv khoom kom ntseeg tau tias lawv lub tshuab ejection quab yuam, mob stroke, thiab tus pin qhov qauv raws nraim nrog peb cov pwm tsim. Yog hais tias koj lub tshuab ejection system tsis mus txog par, koj yuav tau txais preforms uas daig nyob rau hauv pwm, los yog uas muaj ejector tus pin cim rau saum npoo, uas yog defects koj kho tsis tau. Thiab cia peb tsis txhob hnov qab pwm kub tswj. Peb ib txwm pom zoo kom ua ke pwm pwm kub tswj, tsim txoj cai rau hauv lub tshuab, nrog lub computer- tswj cua sov, kev saib xyuas tsis zoo, thiab kev tswj xyuas siab. Yog tias koj cov pwm kub tsis zoo ib yam ntawm txhua qhov kab noj hniav, koj yuav tau txais cov preforms uas muaj cov phab ntsa sib txawv, qib crystallinity sib txawv, thiab tag nrho cov tswv ntawm lwm yam tsis xws luag.
Lwm yam khoom siv uas tseem ceeb heev yog kev tuav tswj, tshwj xeeb yog cov neeg hlau. Rau siab -PET preform ntau lawm, ob-chaw nres tsheb sab- nkag neeg hlau nrog pwm- sab nraum cua txias tsis yog- sib tham. Peb tsim peb cov pwm los ua haujlwm seamlessly nrog cov neeg hlau no, vim tias lawv tsis yog ua kom cov khoom lag luam nrawm dua -lawv ua kom zoo dua qub. Cov neeg hlau zoo tshaj plaws nyob rau hauv kev ua lag luam muaj cov dej ntws txias hauv cov raj preform, yog li koj tuaj yeem qhib pwm thaum cov preforms tseem nyob ntawm 130-140 degrees Celsius, coj lawv tawm, thiab cia lawv txias txias ntawm cov neeg hlau tes thaum lub tshuab twb kaw cov pwm rau kev txhaj tshuaj tom ntej. Qhov no txiav 6 mus rau 7 vib nas this ntawm lub voj voog lub sij hawm, tab sis qhov tseem ceeb tshaj, nws cia cov preforms txias nyob rau hauv ib tug tswj, uniform txoj kev, yog li ntawd lawv tsis warp los yog tsim nyob rau hauv kev ntxhov siab uas yuav ua rau muaj teeb meem thaum lub sij hawm tshuab molding. Peb kuj tseem pom zoo kom cov neeg hlau uas muaj qhov zoo ntawm lub cev muaj zog nkhaus kom nrawm dua, txav tau yooj yim, thiab kev saib xyuas kev nyab xeeb tag nrho -txoj haujlwm kev nyab xeeb cuam tshuam, kev txwv kev mus ncig, pwm de-molding sensors, thiab preform placement sensors. Yog tias koj tus neeg hlau tsis ntseeg siab, koj yuav raug cuam tshuam nrog cov khoom poob qis, misfeeds, thiab ntau lub sij hawm poob, tsis txhob hais txog cov preforms puas.
Tam sim no, txawm hais tias koj muaj cov khoom zoo tshaj plaws, cov pwm zoo tshaj plaws, thiab cov cuab yeej zoo tshaj plaws, koj tseem yuav ua qhov phem preforms yog tias koj cov txheej txheem tsis raug hu ua zoo kawg nkaus. Qhov no yog qhov uas cov roj hmab tau raws txoj kev, thiab peb siv sijhawm ntau rau qhov no nrog peb cov neeg siv khoom ntau dua li yuav luag txhua yam. Thaum peb ua pwm sim rau tus neeg siv khoom, 90% ntawm cov teeb meem thawj zaug peb pom tsis yog nrog pwm nws tus kheej-lawv nrog cov txheej txheem tsis siv neeg siv. Txhua qhov kev txwv tsis pub muaj teeb meem, thiab lawv txhua tus cuam tshuam nrog ib leeg, yog li koj tsis tuaj yeem tweak ib yam hauv kev sib cais thiab xav tias yuav kho qhov teeb meem.
Cia peb pib nrog kev txhaj tshuaj kub. Koj yuav tsum tau txais PET resin kub txaus kom yaj tag nrho thiab ntws tusyees mus rau hauv pwm kab noj hniav, tab sis tsis kub li ntawd nws degrades. Peb tau pom tias qhov chaw qab zib rau feem ntau lub raj mis - qib PET yog nyob nruab nrab ntawm 270 thiab 290 degrees Celsius, tab sis nws hloov pauv nyob ntawm cov resin's IV, pwm tsim, thiab txawm tias qhov kub thiab txias hauv lub Hoobkas. Yog tias qhov kub thiab txias dhau lawm, koj yuav tau txais resin degradation, uas ua rau muaj AA cov ntsiab lus siab, yellowing ntawm preforms, thiab cov pob dub los ntawm cov khoom hlawv. Yog tias nws qis dhau, cov resin yuav tsis yaj tag, ua rau luv luv txhaj tshuaj, ntws cov cim, thiab weld kab nyob rau hauv lub preforms.
Tom qab ntawd muaj qhov txhaj tshuaj siab thiab ceev. Koj xav tau lub siab txaus los sau cov pwm kom tiav, tshwj xeeb tshaj yog cov ntu nyias ntawm lub caj dab preform thiab lub cev, tab sis lub siab ntau dhau yuav ua rau lub teeb, lossis ua rau cov pwm puas. Kev txhaj tshuaj ceev yuav tsum tau sib npaug ib yam nkaus thiab- nrawm dhau, thiab koj tau txais lub dav hlau, cua ntxiab, thiab npuas hauv qhov preform; qeeb dhau, thiab cov khoom pib txias ua ntej cov pwm puv, ua rau kev txhaj tshuaj luv luv lossis tsis sib xws ntawm phab ntsa tuab. Peb ib txwm ua hauj lwm nrog peb cov neeg muas zaub los tsim ib tug multi-stage txhaj profile, pib nrog ib tug qeeb sau kom tsis txhob jetting, ces ramping li ceev mus sau cov kab noj hniav kom tiav, ua ntej hloov mus rau ib tug tswj pob thiab tuav theem.
Tom qab ntawd muaj lub sijhawm txias. Qhov no yog ib qho ntawm qhov tsis zoo tshaj plaws hauv PET preform ntau lawm, thiab nws yog qhov uas ntau tus neeg siv khoom yuam kev. Yog tias koj tsis txias lub preform txaus nyob rau hauv pwm, nws yuav warp thaum koj eject nws, los yog tsim nyob rau hauv kev ntxhov siab uas ua rau nws tawg thaum lub sij hawm tshuab molding. Tab sis yog tias koj txias nws ntev heev, koj nyob nraum nkim lub sij hawm, uas tua koj cov khoom tsim tau thiab profitability. Peb tau pom tias lub sijhawm ua kom txias zoo nyob ntawm qhov preform phab ntsa thickness, pwm kub, thiab cov khoom siv crystallinity tus nqi. Rau tus qauv 15.2 gram dej lub raj mis preform, peb tab tom saib nyob ib ncig ntawm 3 mus rau 4 vib nas this ntawm lub sijhawm txias hauv pwm, tab sis qhov ntawd tuaj yeem hloov pauv ntau raws li lwm qhov tsis muaj. Thiab cia peb tsis txhob hnov qab lub sij hawm plasticization. Yog tias koj lub sij hawm plasticization luv dhau lawm, koj yuav tau txais cov khoom tsis raug hauv kev txhaj tshuaj, uas ua rau muaj qhov tsis xws luag hauv qhov preform. Yog tias nws ntev dhau lawm, cov khoom zaum hauv lub thoob ntev dhau, degrades, thiab koj tau txais cov ntsiab lus AA siab thiab discoloration. Peb tau pab peb cov neeg muas zaub tau lawv lub sij hawm plasticization cia li 3.8 vib nas this rau ib tug 15.2 gram preform, thaum tseem tuav tag nrho cov yaj homogeneity, thiab qhov ntawd tau ua ib tug loj sib txawv nyob rau hauv ob qho tib si lawv lub sij hawm voj voog thiab lawv preform zoo.
Qhov kawg tab sis yeej tsis tsawg kawg, kev tswj kom zoo thiab kev kuaj pom tsis raug. Koj tuaj yeem ua txhua yam kev xaiv zoo nrog cov khoom siv, pwm, cov khoom siv, thiab cov txheej txheem, tab sis yog tias koj tsis ntes cov khoom tsis raug ua ntej lawv tawm ntawm lub qhov rooj, koj yuav muaj ntau cov neeg siv khoom tsis zoo siab, thiab cov nqi xa rov qab ntau. Kev tshuaj xyuas phau ntawv ib txwm tsis txiav nws rau siab - ntim ntau lawm ntxiv- tib neeg tau nkees, lawv nco me me tsis xws luag, thiab lawv tsis tuaj yeem khaws 8- lub sijhawm thib ob. Tias yog vim li cas peb tam sim no ua hauj lwm nrog tag nrho peb cov neeg muas zaub los integrate sib sib zog nqus kev kawm-raws li kev kuaj xyuas lub tshuab rau hauv lawv cov kab ntau lawm, txoj cai nrog peb cov pwm.
Peb tau ua qhov kev sim dav dav nrog cov kev sib txawv ntawm cov lus sib txawv, suav nrog Bi Se Net V2, Deep Lab V3+, AFFormer, thiab PIDNet, thiab peb tau pom tias PIDNet muab qhov sib npaug zoo tshaj plaws ntawm qhov raug thiab nrawm rau qhov tseeb - lub sijhawm kuaj pom qhov tsis zoo. Peb tau pab cov neeg muas zaub tsim lawv tus kheej preform defect datasets, nrog ntau txhiab tus duab annotated npog qhov feem ntau defects: dub me ntsis, npuas, khawb, ntws cov cim, luv luv txhaj, thiab phab ntsa thickness variations. Cov tshuab no tuaj yeem kuaj xyuas qhov tsis xws li me me li ib feem ntawm ib millimeter, sau cov cheeb tsam tsis xws luag hauv lub sijhawm, thiab txheeb xyuas qhov tsis xws li preforms ua ntej lawv tseem ua rau cov kab ntim khoom. Tab sis nws tsis yog hais txog kev ntes cov teeb meem xwb-peb siv cov ntaub ntawv los ntawm cov cuab yeej kuaj xyuas no los pab peb cov neeg siv khoom zoo- kho lawv cov txheej txheem thiab txawm tias lawv cov pwm tsim. Yog tias peb pib pom ntau qhov tsis xws luag nyob rau hauv ntau qhov kab noj hniav, peb tuaj yeem rov qab los kho qhov kub thiab txias, siab, lossis lub sijhawm txias los kho qhov teeb meem ntawm qhov chaw, tsis yog tsuas yog txheeb xyuas qhov tsis zoo.
Thaum kawg ntawm lub hnub, ua kom siab - zoo PET preforms yog tag nrho hais txog kev xyuam xim rau cov ntsiab lus, thiab nkag siab tias txhua yam ntawm cov saw hlau tsim muaj cuam tshuam nrog lwm tus. Raws li lub Hoobkas preform pwm, peb txoj haujlwm tsis yog tsuas yog tsim thiab tsim pwm zoo xwb- nws yog los pab peb cov neeg siv khoom ua kom zoo dua txhua kauj ruam ntawm lawv cov txheej txheem tsim khoom, los ntawm cov resin lawv yuav mus rau qhov tsis xws luag uas lawv siv, kom ntseeg tau tias lawv ua tau zoo, siab - zoo preforms txhua txhua lub sijhawm. Nws tsis yog hais txog kev nrhiav ib qho chaw ua khawv koob lossis ib qho khoom siv uas yuav kho tag nrho koj cov teeb meem - nws yog hais txog kev ua kom zoo rau txhua qhov ntawm cov txheej txheem, thiab niaj hnub saib xyuas thiab kho kom koj cov khoom ua haujlwm zoo. Yog tias koj tuaj yeem ua tau li ntawd, koj yuav tsis tsuas yog txo cov khib nyiab thiab poob qis, tab sis koj tseem yuav tsim lub koob npe nrov rau kev ua qee qhov zoo tshaj plaws PET preforms hauv kev lag luam.