Ntawm tag nrho cov tseem ceeb ntawm lub tshuab txhaj tshuaj molding tshuab, cov ntsia hlau yog lub hauv paus tseem ceeb uas txiav txim siab qhov ua tau zoo ntawm plasticization, qhov zoo ntawm cov khoom molded, thiab kev pabcuam lub neej ntawm lub tshuab nws tus kheej. Ntau tus neeg tsuas yog tsom rau ntawm lub tshuab tonnage lossis clamping quab yuam thaum saib xyuas kev xaiv ntawm cov ntsia hlau; Yog li ntawd, lawv ntsib ntau yam teeb meem xws li cov cim ntws, scorching, cov khoom degradation, xim txawv, tsis sib xws plasticization, thiab cov khoom tsim tawm. Nyob rau hauv kev muaj tiag, thaum lub pwm dictates cov duab sab nraud ntawm cov khoom, cov ntsia hlau tswj cov khoom ntawm cov khoom yas nws tus kheej. Kev ua cov ntaub ntawv sib txawv lossis kev tsim cov khoom sib txawv yuav tsum tau siv cov ntsia hlau tshwj xeeb sib xws; Yog li, kev xaiv kom zoo ntawm cov ntsia hlau yog qhov tseem ceeb ua ntej kom ntseeg tau ruaj khov txhaj tshuaj molding ntau lawm.
Raws li cov ntsiab lus tseem ceeb ntawm lub tshuab txhaj tshuaj molding tshuab, cov ntsia hlau feem ntau ua haujlwm ntawm kev xa cov yas, cua sov thiab shear- melting cov khoom, metering thiab accumulating lub yaj, thiab txhaj cov yas molten nyob rau hauv siab. Tom qab cov yas pellets nkag mus rau hauv lub thoob los ntawm lub hopper, lawv yog uniformly melted los ntawm ib tug khoom lub xeev mus rau hauv ib tug kua los ntawm kev sib xyaw ua ke ntawm cov ntsia hlau rotational propulsion, cua sov los ntawm lub thoob sab nrauv phab ntsa, thiab lub shear tshav kub generated los ntawm cov ntsia hlau nws tus kheej. Cov ntsia hlau txoj kab uas hla, ntev - mus rau - txoj kab uas hla piv, dav dav qhov tob, cov khoom hardness, kev kho saum npoo, thiab yaj- cov qauv xa ncaj qha cuam tshuam rau plasticization efficiency, yaj uniformity, thiab cov khoom thermal stability-nrog rau qhov cuam tshuam rau cov teeb meem xws li thermal decomposition, carbonization, carbon buildup, thiab dub streaks.
Thaum xaiv cov ntsia hlau rau kev tsim khoom txhua hnub, thawj kauj ruam yog kom paub qhov txawv ntawm cov khoom siv raw. Rau cov khoom siv dav dav - lub hom phiaj yas- xws li PP, PE, thiab PS- uas nthuav tawm cov dej ntws zoo, cov ntsiab lus melting tsawg, thiab muaj zog thermal stability, tus qauv dav dav - lub hom phiaj ntsia hlau yog txaus kom ua tau raws li qhov yuav tsum tau ua. Xws li cov ntsia hlau ua kom cov yas du thiab muab lub qhov rais ua haujlwm dav, ua rau lawv haum rau feem ntau ntawm cov khoom siv niaj hnub, pob tawb, cov yeeb nkab fittings, thiab cov khoom yas zoo tib yam. ABS, ntawm qhov tod tes, yog cais raws li qhov nruab nrab - qib engineering yas; nws nta qhov nruab nrab molding kub ntau thiab tsawg corrosiveness, txhais tau tias nws tseem tuaj yeem ua tiav los ntawm kev siv dav dav - lub hom phiaj ntsia hlau. Txawm li cas los xij, rau lub sij hawm ntev - lub sij hawm, siab - ntim ntau lawm, nws raug nquahu kom xaiv qhov kev hloov kho dua tshiab, hnav- cov ntsia hlau tiv taus kom txo qis tiam ntawm cov hmoov yas hmoov impurities los ntawm kev puas tsuaj.
Thaum ua cov yas engineering thiab cov polymers tshwj xeeb-xws li PC, PA (Nylon), POM, PMMA, thiab PVC- kev xaiv cov ntsia hlau tsim nyog suav nrog cov kev cai nruj. PC yog tus cwj pwm los ntawm cov pob tshab siab, siab viscosity, thiab qhov nyuaj hauv plasticization; Tsis tas li ntawd, nws tsis tuaj yeem tiv taus qhov ntev ntawm qhov kub thiab txias hauv lub thoob. Yog li ntawd, nws yuav tsum tau ib tug tshwj xeeb ntsia hlau featuring ib tug siab compression piv, siab shear muaj peev xwm, thiab ib tug heev polished nto tag kom ib tug uniform thiab pob tshab yaj, yog li tiv thaiv tsis xws luag xws li nyiaj streaks, ntws cov cim, dub me ntsis, thiab tsis txaus clarity. Nylon (PA) yog hygroscopic heev, nthuav tawm cov kev hloov pauv tseem ceeb hauv kev coj cwj pwm thaum yaj; nws kuj tso cov kev xav tau siab heev ntawm cov ntsia hlau hnav tsis kam, yog li xav tau cov ntsia hlau tsim los tiv thaiv corrosion thiab puas. PVC yog cov cua sov- cov yas rhiab heev uas decomposes yooj yim ntawm qhov kub thiab txias, tsim cov roj corrosive. Yog li ntawd, nws yog ib qho tseem ceeb uas yuav tsum tau ua haujlwm tshwj xeeb corrosion-cov ntsia hlau thiab cov thoob los tiv thaiv cov khoom siv degradation, thaum tib lub sijhawm tswj hwm kev tswj hwm nruj ntawm shear-induced cua sov los tiv thaiv cov yas decomposition thiab discoloration.
Qhov thib ob, lub hau ntswj txoj kab uas hla yuav tsum raug xaiv raws li cov khoom ntim ntau lawm thiab qhov yuav tsum tau txhaj tshuaj hnyav. Ib txoj kab uas hla loj dua ua rau muaj ntau dua - ntim ntim thiab cov yas yas sai dua thiab tso tawm, ua rau nws tsim nyog rau cov khoom loj, tuab - qhov chaw phab ntsa, thiab siab - ntim, siab - ceev ntau lawm. Conversely, ib tug me me txoj kab uas hla muaj ntau dua metering precision, ua rau nws zoo tagnrho rau me me, precision Cheebtsam, nyias-walled qhov chaw, thiab siab- raug hluav taws xob accessories. Cov lus qhia dav dav hauv kev lag luam dictates tias tag nrho qhov hnyav ntawm cov khoom tiav yuav tsum poob nyob rau hauv thaj tsam ntawm 20% mus rau 75% ntawm cov ntsia hlau txoj kev txhaj tshuaj muaj peev xwm; siv qhov hnyav txhaj tshuaj uas me dhau ua rau cov yas nyob hauv lub thoob rau lub sijhawm ntev, ua rau scorching, yellowing, los yog decomposition, whereas siv txhaj koob tshuaj tivthaiv hnyav uas loj heev ua rau tsis txaus plasticization, tsis muaj pwm puv, thiab cov khoom tsis xws li kev txhaj tshuaj luv luv lossis shrinkage.
Cov ntsia hlau ntev - mus rau - txoj kab uas hla (L/D) piv yog lwm qhov tseem ceeb hauv txoj kev xaiv. Qhov sib piv L / D siab dua ua rau txoj kev thauj mus ntev dua rau cov yas hauv lub thoob, ua kom yooj yim dua cua sov thiab yaj, nrog rau kev sib xyaw ua haujlwm zoo dua; qhov no ua rau nws zoo tagnrho rau kev ua cov yas hloov kho, iav- fiber ntau- cov khoom siv ntxiv, thiab cov khoom uas xav tau cov xim masterbatch sib xyaw. Conversely, ib tug ntsia hlau nrog ib tug qis L / D piv muab ceev plasticization speeds thiab luv nyob rau hauv lub sij hawm, ua rau nws haum rau tshav kub- cov yas rhiab heev los ntawm kev txo qhov kev pheej hmoo ntawm siab - kub degradation. Thaum tus qauv L/D piv tau pom nyob rau hauv dav dav - lub hom phiaj cov cav tov yog tag nrho txaus rau cov neeg siv khoom yas cov khoom, ua iav- fiber ntau - hloov kho cov ntaub ntawv los yog cov khoom uas yuav tsum tau intensive sib tov yuav tsum tau hloov mus rau ib tug tshwj xeeb ntsia hlau nrog ib tug ntau dua L/D ratio.
Hais txog cov khoom muaj pes tsawg leeg thiab hnav tsis kam, tus qauv nitrided screws yog tsim rau kev ua cov yas ntshiab-tshwj xeeb yog cov uas tsis muaj tshuaj ntxiv lossis iav fibers. Txawm li cas los xij, thaum tsim cov iav-fiber- siv zog PA, iav-fiber-inforced PP, los yog ntxhia- puv cov yas hloov, qhov tawv tawv ntawm cov iav fibers ua rau puas sai sai ntawm cov ntsia hlau ya davhlau. Qhov no ua rau muaj kev tshem tawm ntau ntxiv, kev txhaj tshuaj tsis ruaj khov, cov khoom siv sab hauv rov qab, thiab qhov sib txawv ntawm qhov sib txawv ntawm cov khoom tiav. Yog li ntawd, nws yog ib qho tsim nyog yuav tau xaiv cov ntsia hlau bimetallic thiab chim sib dhos. Cov rooj sib txoos no muaj qhov zoo tshaj plaws tag nrho hardness nrog rau kev txhim kho kev tiv thaiv rau ob qho tib si hnav thiab corrosion, yog li txuas ntxiv kev pab cuam lub neej thiab txo cov nqi tsim khoom cuam tshuam nrog kev hloov pauv ntau zaus.
Tsis tas li ntawd, cov ntsia hlau cov qauv yas, cov khoom tsis sib xws nrog - rov qab lub nplhaib, thiab lub tshuab txhaj tshuaj yuav tsum raug xaiv los ua ib qho kev sib koom ua ke. Tsuas yog thaum cov khoom siv plasticizing tau raug sib raug zoo rau cov ntsia hlau specifications tuaj yeem ua kom muaj kev txhaj tshuaj metering, tiv thaiv yaj rov qab, ruaj khov tuav, thiab txo qhov kev hloov pauv hauv cov khoom hnyav. Ntau qhov chaw tsim khoom feem ntau ntsib teeb meem xws li qhov hnyav ntawm cov khoom lag luam tsis raug, qhov tsis sib xws, thiab kev tsim flash tsis tuaj yeem pom. Ib cag los ntawm cov teeb meem muaj peev xwm nrog cov kev ntsuas kev siv tshuab, cov hauv paus ntsiab lus ntawm cov teeb meem no feem ntau tshwm sim los ntawm kev tsis sib haum xeeb ntawm cov ntsia hlau, hnav ntau dhau kev txwv, lossis kev xaiv tsis tsim nyog ntawm cov khoom.
Hauv cov ntsiab lus, kev xaiv ntawm lub tshuab txhaj tshuaj molding ntsia hlau yuav tsum tsis txhob raug kho raws li qhov yooj yim xaiv, tawm ntawm -- txee tus qauv. Hloov chaw, cov khoom siv raw dictates hom ntsia hlau; cov khoom hnyav txiav txim siab lub taub hau ntsia hlau; ntau lawm yuav tsum tau txhais qhov ntev - mus rau - txoj kab uas hla piv; thiab muaj cov fillers lossis modifiers txiav txim siab txog qib khoom siv. Tsuas yog thaum tus thawj cov cuab yeej tsim kho cov ntsia hlau-raws li tus neeg siv khoom cov khoom siv tshwj xeeb, qhov ntev ntawm cov khoom, cov khoom ntim khoom, thiab seb puas muaj fiber ntau koom nrog-lub kaw lus tuaj yeem ua tiav cov yas zoo li qub, kev tso tawm ruaj khov, thiab cov txiaj ntsig siab, tag nrho thaum lub zog tseem tshuav - zoo. Ntxiv mus, qhov kev ua kom haum no txo qis cov cuab yeej ua haujlwm tsis zoo thiab txo cov nqi tu lub sijhawm ntev, ua haujlwm raws li qhov yuav tsum tau ua ua ntej rau lub tshuab txhaj tshuaj molding kom xa nws qhov kev ua tau zoo tshaj plaws.
