Cov khoom siv tsis zoo tuaj yeem ncaj qha ua rau cov khoom siv tsis zoo hnav, nce kev ua haujlwm tsis zoo, thiab cov khoom siv tsis tu ncua, thiab tuaj yeem cuam tshuam rau kev ruaj ntseg ntawm tag nrho cov txheej txheem tsim khoom thiab cov nqi tsim khoom los ntawm cov khoom siv raw mus rau theem.
Qhov cuam tshuam ntawm Key PVC Resin Properties
Degree ntawm Polymerization (K- tus nqi) thiab Molecular Luj: Qhov siab dua ntawm polymerization, qhov zoo ntawm cov khoom siv ntawm cov yeeb nkab, xws li lub zog tensile thiab kev cuam tshuam lub zog. Txawm li cas los xij, tib lub sijhawm, cov resin's processability thiab flowability deteriorate, ua rau muaj kev xav tau ntau dua torque thiab siv zog ntau ntxiv thaum lub sij hawm extrusion, uas qhov chaw xav tau ntau dua ntawm extruder lub zog tsav thiab lub zog ntsia hlau. Yog li ntawd, hauv kev tsim khoom, nws yog ib qho tsim nyog los xaiv cov qib resin tsim nyog raws li cov hom phiaj kev ua haujlwm ntawm cov yeeb nkab thiab cov peev txheej ntawm cov khoom siv.
Thermal Stability: PVC yog lub tshav kub- cov khoom rhiab heev, thiab nws qhov kub thiab txias decomposition yog ze rau nws qhov kub thiab txias. Yog hais tias cov resin nws tus kheej tsis zoo thermal stability, nws yog feem ntau decomposition txawm nyob rau hauv ib txwm ua kub, ua hydrogen chloride (HCl) gas nrog rau discoloration thiab charred residues.
Qhov tshwm sim: Cov khoom decomposition no tsis tsuas yog ua rau cov ntsia hlau, lub thoob, thiab tuag tab sis kuj ua rau muaj qhov tsis xws luag ntawm cov yeeb nkab sab hauv phab ntsa, xws li yellowish - xim av streaks thiab cov pob dub. Nyob rau tib lub sijhawm, cov roj HCl uas tsim los ntawm kev puas tsuaj ntxiv catalyzes decomposition, tsim lub voj voog vicious.
Volatile (Moisture) Cov ntsiab lus: Yog tias cov resin damp los yog muaj cov ntsiab lus tsis haum siab heev, nws yuav vaporize thaum lub sij hawm extrusion txheej txheem.
Qhov tshwm sim: Yog tias cov dej tsis tuaj yeem raug tshem tawm raws sijhawm, nws yuav ua rau muaj npuas nyob hauv cov yeeb nkab phab ntsa thiab ib qho tsis sib xws sab hauv; nyob rau hauv cov xwm txheej hnyav, nws yuav ua rau cov yeeb nkab tsis ua raws li cov qauv kev ua tau zoo. Cov dej noo ntau dhau tuaj yeem ua rau HCl tiam, cov khoom siv corroding.
Impurities thiab Dub / Yellow Spots: Lub cev impurities lossis cov xim dub / daj hauv cov khoom siv raw tsis tuaj yeem ua plasticized thiab yuav dhau los ua cov ntsiab lus kev ntxhov siab.
Qhov tshwm sim: Cov impurities no tsim pitting, pits, los yog tsa qhov chaw ntawm cov yeeb nkab nto, ua rau muaj kev cuam tshuam loj heev rau cov tsos thiab lub zog txhua yam. Raws li cov impurities nyuaj dhau los ntawm extruder, lawv ua zoo li abrasives, nrawm hnav ntawm cov ntsia hlau thiab lub thoob.
Qhov cuam tshuam ntawm Additives thiab Fillers
Stabilizers: Lawv txoj haujlwm yog los tiv thaiv cov thermal degradation ntawm PVC thaum ua.
Qhov tshwm sim: Yog tias lub stabilizer tsis zoo lossis siv tsis txaus, cov khoom yuav degrade ntxov ntxov. Nyob rau hauv ntau lawm, qhov no manifests raws li discoloration ntawm cov yeeb nkab nto thiab ib tug txo nyob rau hauv cov khoom qhov cuam tshuam thiab tensile zog.
Lubricants: Qhov sib npaug ntawm sab hauv thiab sab nraud lubrication yuav tsum tau tswj kom meej meej kom cov khoom ntws zoo los ntawm cov cuab yeej tsis ua raws li cov khoom siv hlau.
Qhov tshwm sim: Lub lubrication tsis txaus ua rau muaj kev nce siab hauv lub zog thiab siab dua lub taub hau tuag, nce cov khoom siv thauj khoom thiab siv zog. Lub lubrication ntau dhau yuav ua rau cov khoom plam ntawm cov ntsia hlau, txo cov zis thiab ua rau muaj kev puas tsuaj.
Fillers (piv txwv li, calcium carbonate CaCO₃): Ntxiv rau qhov tsim nyog tuaj yeem txo cov nqi, tab sis kev siv ntau dhau lossis siv tsis raug yuav ua rau muaj kev phom sij ntau dua li qhov zoo.
Qhov tshwm sim: Cov khoom siv ntau dhau yuav txo cov khoom ntws, ua rau txo qis hauv cov yeeb nkab qhov cuam tshuam lub zog thiab tensile lub zog. Qhov tseem ceeb tshaj, cov khoom ua kom qhuav qhuav muaj cov dej ntws tsis zoo, uas tuaj yeem ua rau muaj teeb meem kev noj zaub mov thiab txawm tias thaiv cov khoom noj nkag. Lawv lub siab hardness thiab abrasiveness hnyav hnyav hnyav hnyav rau ntawm cov ntsia hlau extruder thiab chim.
Kev cuam tshuam rau cov khoom siv Lifespan
Qhov cuam tshuam ncaj qha tshaj plaws uas qis - cov khoom siv raw zoo ua rau cov yeeb nkab extruders yog qhov ua kom lub cev hnyav thiab tsim kua muag ntawm lawv cov khoom tseem ceeb.
Screw thiab Barrel Wear: Cov khoom siv tawv tawv, cov khoom siv tsis muaj yas, lossis cov khoom tsis huv yog qhov tseem ceeb ntawm kev hnav.
Qhov tshwm sim: Kev hnav nrawm ntawm cov ntsia hlau thiab lub thoob yuav ua rau cov yas tsis zoo, cov khoom siv txo qis, thiab tuaj yeem ua rau cov ntsia hlau puas, ncaj qha nce cov khoom tu thiab hloov cov nqi.
Khoom Siv Corrosion: HCl roj tso tawm thaum lub sij hawm thermal decomposition ntawm PVC yog ib yam khoom corrosive heev.
Cov txiaj ntsig: Nws corrodes cov ntsia hlau, chim, tuag, thiab qhov cua tshuab, ua rau lub neej ua haujlwm ntawm cov khoom siv luv luv.
Kev cuam tshuam rau kev ua tau zoo thiab cov khoom lag luam tawm los
Kev tsis ruaj khov ntau lawm: Kev hloov pauv ntawm cov khoom siv raw tuaj yeem hloov cov khoom siv rheological tus cwj pwm, yuam cov neeg ua haujlwm kom nquag kho cov txheej txheem xws li qhov kub thiab txias ceev, ua rau nws nyuaj rau kev ruaj khov, siab - tso zis lub xeev.
Cov khoom lag luam nce ntxiv: Ntau yam teeb meem raw khoom ncaj qha tshwm sim raws li cov khoom tsis xws luag. Piv txwv li:
Rough, Dull Surface: Feem ntau muaj feem xyuam rau kev siv cov roj nplua nyeem tsis raug, tsis zoo plasticization, lossis kub tuag tsawg heev.
Yeeb Nkab Warping: Ua los ntawm cov phab ntsa tuab tsis sib xws los yog tsis sib xws, thiab muaj feem cuam tshuam rau kev ua haujlwm ntawm plasticization thiab kev tsim cov khoom siv raw.
Hla -sectional npuas: Ncaj qha los ntawm cov dej noo ntau dhau ntawm cov khoom siv raw lossis cov khoom tawg.
Hauv cov ntsiab lus, qhov zoo ntawm cov khoom siv raw yog txuas ncaj qha rau kev ua haujlwm ntawm extruder, qhov hnyav ntawm kev hnav thiab tsim kua muag, kev siv lub zog, nrog rau qhov zoo thiab cov khoom tsim tawm ntawm cov khoom kawg. Kev kho cov khoom siv raw khoom zoo tswj raws li cov kauj ruam tseem ceeb hauv cov txheej txheem tsim khoom yog qhov tseem ceeb rau kev ua kom lub sijhawm ntev -, ruaj khov, thiab ua haujlwm zoo ntawm cov kab ntau lawm.