Cov txheej txheem tsim cov ntawv PET

(1) Cov ntaub ntawv raw ntawm cov ntawv PET

Ib yam li lwm cov yas, qhov kev ua tau zoo ntawm PET ntawv muaj feem cuam tshuam nrog qhov hnyav molecular. Qhov viscosity intrinsic txiav txim siab qhov hnyav molecular. Qhov ntau dua qhov intrinsic viscosity, qhov zoo dua qhov khoom siv lub cev thiab tshuaj lom neeg, tab sis qhov tsis zoo fluidity ua rau molding nyuaj. Qhov qis dua qhov intrinsic viscosity, qhov tsis zoo nws cov khoom siv lub cev thiab tshuaj lom neeg thiab qhov cuam tshuam tsis zoo. Yog li ntawd, qhov intrinsic viscosity ntawm PET pob tshab ntawv yuav tsum tau xaiv los ntawm 0.8dl / g-0.9dl / g.

(2) Cov txheej txheem tsim khoom.

Cov khoom siv tseem ceeb ntawm PET daim ntawv pob tshab yog: crystallization tower, drying tower, extruder, tshuab taub hau, peb-roller calender, thiab coiler.

Cov txheej txheem ntau lawm yog: cov khoom siv raw crystallization-qhuav-extrusion plasticization-extrusion molding-calendering thiab shaping-winding khoom.

Kauj ruam thawj zaug yog crystallization. Cov PET slices raug cua sov thiab crystallized hauv lub crystallization tower kom npaj cov molecules kom raug, thiab tom qab ntawd qhov kub hloov pauv iav ntawm cov slices nce ntxiv. Lub hom phiaj yog los tiv thaiv kev nplaum thaum lub sijhawm ziab thiab thaiv ntawm lub hopper. Crystallization feem ntau yog ib kauj ruam tseem ceeb. Crystallization siv sijhawm 30 feeb txog 90 feeb thiab qhov kub tsawg dua 149 ° C.

Kauj ruam thib ob yog ziab. Vim tias nyob rau hauv qhov kub siab, dej tuaj yeem ua rau hydrolytic degradation ntawm PET, ua rau nws cov yam ntxwv adhesion txo qis, thiab nws cov khoom lub cev, tshwj xeeb tshaj yog lub zog cuam tshuam, yuav txo qis nrog qhov txo qis ntawm molecular hnyav. Yog li ntawd, PET yuav tsum tau ziab ua ntej yaj thiab extruding kom txo cov dej noo. Nws cov dej noo yuav tsum tsawg dua 0.005%. Lub tshuab ziab dehumidifying siv rau ziab. Vim tias cov khoom PET yog hygroscopic, dej noo yuav tsim cov molecular bonds thaum nws nkag mus tob rau hauv qhov chaw ntawm cov slices. Lwm ib feem ntawm cov dej noo yuav muaj nyob tob hauv cov slices, ua rau ziab nyuaj. Yog li ntawd, cua kub ib txwm tsis tuaj yeem siv. Lub ntsiab lus cua kub dew yuav tsum qis dua -40C, thiab cua kub raug coj mus rau hauv lub hopper ziab los ntawm lub voj voog kaw rau kev ziab tas mus li.

Kauj ruam thib peb yog extrusion molding. Tom qab crystallization thiab ziab, PET raug hloov mus ua polymer nrog lub melting point pom tseeb. Lub molding kub ntawm polymer yog siab thiab qhov kub tswj ntau yam yog nqaim. Ib tug barrier ntsia hlau tshwj xeeb tsim rau polyester yog siv los cais unmelt pellets thiab yaj, uas yog pab rau kev tswj lub shear txheej txheem ntev dua thiab ua kom cov zis ntawm extruder. Siv lub taub hau tshuab die di ncauj yooj ywm nrog ib tug streamlined flow blocking pas nrig. Lub taub hau tshuab muaj ib tug taw tes cone zoo li. Lub streamlined flow channel thiab khawb-dawb pwm daim di ncauj yuav tsum muaj qhov chaw tiav zoo. Lub cua sov ntawm lub taub hau tshuab muaj ib tug draining thiab ntxuav muaj nuj nqi. Lub tuag daim di ncauj qhov sib txawv yuav tsum xyuas kom meej zoo uniformity. Lub sib npaug tuag daim di ncauj qhov sib txawv ntawm lub taub hau tshuab ncaj qha cuam tshuam rau lub lateral thickness deviation ntawm daim ntawv thiab lub calendering flatness. Thaum extruding rau hauv daim ntawv, qhov kub sib xws ntawm thaj chaw pem hauv ntej ntawm lub fuselage, thaj chaw nruab nrab ntawm lub fuselage, thaj chaw tom qab ntawm lub fuselage, lub vijtsam hloov pauv, thiab lub taub hau tshuab yog 240 ° C-260C, 265 ° C-275 ° C, thiab 260 ° C-265 ° C feem. , 260 ° C-265 ° C, 255 ° C-265 ° C.

Kauj ruam plaub yog kom txias thiab teeb tsa. Tom qab cov yaj tawm ntawm lub taub hau tshuab, nws ncaj qha mus rau hauv peb-roller calender rau calendering thiab txias. Qhov deb ntawm peb-roller calender thiab lub taub hau tshuab feem ntau khaws cia ntawm kwv yees li 8cm, vim tias yog qhov deb loj dhau, daim ntawv yuav yooj yim sag thiab wrinkle., ua rau daim ntawv tiav tsis zoo. Tsis tas li ntawd, vim qhov deb ntau dhau, qhov cua sov dissipation thiab txias qeeb dhau thiab cov siv lead ua yuav tig dawb, uas tsis zoo rau calendering. Lub tshuab calendering peb-roller muaj cov menyuam sab saud, nruab nrab thiab qis dua. Lub axis ntawm nruab nrab roller yog kho. Thaum lub sijhawm txias thiab calendering, qhov kub ntawm qhov chaw roller yog 40 ° C-50 ° C. Lub axis ntawm cov menyuam sab saud thiab qis dua tuaj yeem txav mus rau saum thiab nqis. Qhov kev txav mus rau saum thiab nqis ntawm lub axis kho qhov sib txawv ntawm yob. Qhov kub ntawm cov menyuam sab saud thiab qis dua yog 30 ° C-60 ° C thiab 52 ° C-68 ° C feem. Peb lub rollers yuav tsum xyuas kom meej tias qhov ceev sib dhos thiab qhov ceev yuav tsum siab dua qhov ceev extrusion. Lub hom phiaj yog los offset Qhov kev nthuav dav ntawm cov khoom thaum tawm hauv lub pwm ua rau lub zog sab hauv ntawm daim ntawv tsis muaj zog, ua rau cov wrinkles ploj mus. PET yuav crystallize hauv qhov ntau ntawm 100C-250 ° C, thiab qhov nrawm crystallization sai dua ntawm 140 ° C-180 ° C, yog li crystallization tsuas yog siv ob peb feeb xwb kom tiav. PET yuav tsum dhau los ntawm thaj chaw kub crystallization no sai sai, thiab qhov kub ntawm peb lub rollers yuav tsum tau tswj hwm nruj me ntsis.

Kauj ruam thib tsib yog ua kom muaj kev rub thiab coiling. Daim ntawv tawm los ntawm lub calender roller thiab nkag mus rau hauv lub cuab yeej rub los ntawm lub roller qhia. Lub cuab yeej rub muaj lub roller roj hmab nquag thiab lub roller roj hmab tsis nquag. Lub siab cua nias ob lub rollers feem ntau kom tiv thaiv daim ntawv kom tsis txhob raug flattened vim cov khoom ntawm lub calender roller thaum lub sijhawm ua daim ntawv raug rub los ntawm ob lub rollers mus rau lub cuab yeej winding.

Cov teeb meem zoo sib xws hauv kev tsim cov ntawv pob tshab PET thiab lawv cov kev daws teeb meem

(1) Daim ntawv tsim cov khoom siv lead ua tsis huv. Cov laj thawj suav nrog cov khoom siv raw thiab cov khoom seem. PET daim ntawv lawv tus kheej tsis tsim cov khoom siv lead ua tsis huv. Txawm li cas los xij, thaum lub sijhawm ua cov txheej txheem, vim muaj teeb meem ziab thiab ntau dua lossis tsawg dua cov khoom seem ntxiv, cov khoom tsis huv lossis cov khoom siv raw tsis zoo uas tau qhia vim yog ib puag ncig tsis zoo ua rau muaj teeb meem. Nws tsis tuaj yeem tshem tawm thaum lub sijhawm ua daim ntawv.

(2) Cov kab kab rov tav thiab cov kab dej (cov kab txiv kab ntxwv tev tawv). Cov cim dej yog tshwm sim los ntawm qhov tseeb tias cov khoom ntws los ntawm lub taub hau extruder nkag mus rau hauv lub tshuab calender vim tias tsis muaj cov khoom seem ntawm cov tshuab calender, ua rau daim ntawv tsis raug compacted. Qhov tiav ntawm daim ntawv tsis zoo li cov txiv kab ntxwv tev tawv. Kev daws teeb meem yog tias yuav tsum muaj cov khoom seem pom ntawm cov tshuab calender, thiab cov khoom seem yuav tsum tig sib npaug. Cov kab kab rov tav yog qhov tsis zoo ntawm txoj kev extrusion, ib yam li cov dej ripples ntawm txoj kev calendering. Cov indentations yog tshwm sim los ntawm qhov sib txawv ntawm ob lub tshuab calender. Kev daws teeb meem yog xav tau peb lub tshuab ntawm peb lub tshuab calender. Qhov tseeb ntawm kev tswj ceev ntawm lub tshuab tau zoo dua, thiab qhov tseeb ntawm kev sib dhos kuj yuav tsum tau txhim kho kom txo cov kab kab rov tav.

(3) Daim ntawv muaj xim daj, cov pob dub lossis cov khoom tsis huv, cov kab sib txuas, kev ua kom tsis sib xws, thiab lwm yam. Qhov laj thawj tseem ceeb rau qhov tshwm sim ntawm cov npuas hauv daim ntawv yog tias cov pellets tsis tau qhuav tag thiab cov dej noo ntau dua 0. 005%. Yog tias cov dej noo tsis tau qhuav tag, nws yuav nkag mus tob rau hauv cov hlais kom tsim cov molecular bonds lossis nyob tob hauv cov hlais. Yog tias qhov kub qhuav qis dhau lossis lub sijhawm luv dhau, qhov cuam tshuam ntawm kev ziab yuav raug cuam tshuam. Yog tias cov blisters tshwm sim ntawm daim ntawv, qhov kub thiab lub sijhawm ziab yuav tsum tau kho tam sim ntawd. Qhov laj thawj tseem ceeb rau qhov daj ntawm daim ntawv yog tias qhov kub ziab siab dhau lossis lub sijhawm ziab ntev dhau. Cov kev ntsuas tseem ceeb ntawm lub sijhawm no yog kom txo qhov kub ziab thiab txo lub sijhawm ziab. Lwm qhov laj thawj vim li cas daim ntawv tig daj yog tias qhov kub yaj siab dhau. Lub sijhawm no, qhov kub yaj yuav tsum tau txo qis sai sai. Qhov laj thawj tseem ceeb rau qhov tshwm sim ntawm cov pob dub thiab cov khoom tsis huv hauv daim ntawv yog cov lim dej tawg lossis cov khoom seem PET decomposition hauv extruder.

Cov ntsiab lus tsim cov ntawv PET pob tshab

(1) Cov xwm txheej tseem ceeb rau kev tsim cov ntawv pob tshab PET yog kev tswj lub sijhawm ziab thiab cua sov dew point. Qhov cuam tshuam ziab ncaj qha txiav txim siab lub cev thiab cov khoom siv kho tshuab thiab kev tsim khoom ntawm daim ntawv. Thaum ziab, yuav tsum tau them sai sai rau kev tswj qhov kub thiab sijhawm ziab. Qhov kub thiab sijhawm ziab yuav tsum tsis txhob siab dhau lossis qis dhau. Yog tias dew point tsis tuaj yeem poob, yuav tsum kuaj xyuas lub molecular sieve. Lub molecular sieve laus tsis tuaj yeem nqus cov dej noo hauv huab cua thiab tsis tuaj yeem ua tiav lub hom phiaj ntawm kev ziab slices. Lub sijhawm no, yuav tsum tau hloov lub molecular sieve.

(2) Yog tias qhov kub yaj tshaj 280C, daim ntawv PET yuav ploj xim lossis lwj, yog li qhov kub yaj yuav tsum tswj tau qis dua 280C.

(3) Qhov sib txawv ntawm daim di ncauj tuag ntawm lub taub hau tshuab txiav txim siab qhov tiaj tus thiab tuab sib xws ntawm daim ntawv. Qhov kub ntawm peb lub rollers ua lub luag haujlwm tseem ceeb hauv qhov pob tshab thiab tiav ntawm daim ntawv. PET yaj yuav tsum zam sai sai thaj chaw kub nrog qhov nrawm crystallization sai tshaj plaws. Los ntawm qhov kub yaj mus rau qis dua qhov kub crystallization, qhov deb ntawm lub pwm thiab lub calender roller dhau los ua qhov tseem ceeb heev.

Cov txiaj ntsig tseem ceeb ntawm cov ntawv pob tshab PET yog qhov pom tseeb, cov khoom tiv thaiv roj zoo, cov khoom tiv thaiv zoo, lub zog thiab kev nthuav dav. Cov ntawv pob tshab PET tsis muaj cov khoom ruaj khov thiab cov yas, tsis muaj cov khoom phom sij, thiab lawv cov nqi zoo, yog li lawv tau txais kev nyiam los ntawm cov neeg siv khoom. Cov ntawv pob tshab PET tuaj yeem rov ua dua tshiab thaum lub sijhawm tsim khoom, kev thauj mus los thiab kev siv. Yog li ntawd, cov ntawv pob tshab PET muaj txiaj ntsig zoo rau kev siv. Hauv cov txheej txheem tsim khoom PET, cov kev cai ntawm cov txheej txheem tsim khoom yuav tsum tau ua raws li nruj me ntsis, cov txheej txheem ziab thiab qhov chaw noo ntawm huab cua kub yuav tsum tau tswj hwm, qhov sib txawv ntawm lub tshuab calender thiab qhov sib piv ntawm qhov ceev ntawm cov khoom tom ntej yuav tsum tau tswj hwm zoo, kom txhim kho qhov zoo ntawm cov khoom.