Txhaj tshuaj molding txheej txheem hloov cov lus qhia
Kev tswj hwm ntawm kev txhaj tshuaj molding ceev tau dav siv los ntawm kev txhaj tshuaj molding tshuab manufacturers. Txawm hais tias lub khoos phis tawj tswj kev txhaj tshuaj molding ceev segmentation tswj cov tshuab tau ntev lawm, vim muaj cov ntaub ntawv tseem ceeb, qhov zoo ntawm lub tshuab teeb tsa no tsis tshua muaj coj los ua si. Kab lus no yuav piav qhia txog qhov zoo ntawm kev siv ntau theem ceev txhaj tshuaj molding, thiab qhia luv luv txog nws txoj kev siv hauv kev tshem tawm cov khoom tsis xws luag xws li kev txhaj tshuaj luv luv, ntim cua, thiab shrinkage. duab
Kev sib raug zoo ntawm kev txhaj tshuaj ceev thiab cov khoom zoo ua rau nws yog qhov tseem ceeb rau kev txhaj tshuaj molding. Los ntawm kev txiav txim siab pib, nruab nrab, thiab qhov kawg ntawm qhov sau nrawm ntu, thiab ua tiav qhov kev hloov pauv ntawm ib qho chaw mus rau lwm qhov, qhov ruaj khov ntawm qhov nrawm nrawm tuaj yeem ua kom ntseeg tau los tsim cov qauv xav tau thiab txo qis hauv kev ntxhov siab.
Peb pom zoo cov hauv qab no rau kev faib ceev:
1) Lub nrawm ntawm cov kua dej yuav tsum tsis tu ncua.
2) Kev txhaj tshuaj nrawm yuav tsum tau siv los tiv thaiv cov yaj los ntawm khov thaum lub sijhawm txhaj tshuaj.
3) Qhov chaw txhaj tshuaj ceev yuav tsum tau coj mus rau hauv tus account qhov ceev ceev ntawm qhov chaw tseem ceeb (xws li tus neeg khiav dej num) thaum lub sij hawm qeeb ntawm cov dej nkag.
4) Kev txhaj tshuaj ceev yuav tsum tau lees tias yuav tsum tau nres tam sim tom qab cov kab noj hniav tau sau los tiv thaiv overfilling, flash thiab residual stress.
Lub hauv paus rau kev teeb tsa qhov nrawm ntu yuav tsum coj mus rau hauv tus account geometry ntawm pwm, lwm yam kev txwv tsis pub khiav thiab tsis muaj peev xwm. Kev teeb tsa ceev yuav tsum muaj kev nkag siab meej ntawm cov txheej txheem txhaj tshuaj molding thiab cov ntaub ntawv paub txog, txwv tsis pub, cov khoom zoo yuav nyuaj rau kev tswj. Vim tias qhov dej ntws ntws tsis yooj yim rau kev ntsuas ncaj qha, nws tuaj yeem suav ncaj qha los ntawm kev ntsuas cov ntsia hlau ua ntej nrawm, lossis kab noj hniav siab (kom paub meej tias lub pob valve tsis to).
Cov khoom siv tseem ceeb heev vim tias cov polymers tuaj yeem degrade vim muaj kev ntxhov siab sib txawv, qhov kub ntawm molding tuaj yeem ua rau oxidation hnyav thiab degradation ntawm cov qauv tshuaj, tab sis tib lub sij hawm degradation los ntawm shear yuav me me vim qhov kub thiab txias txo cov viscosity. khoom, txo cov shear kev nyuaj siab. Undoubtedly, ntau theem kev txhaj tshuaj ceev yog qhov zoo heev rau molding cov ntaub ntawv kub-rhiab xws li PC, POM, UPVC thiab lawv cov khoom sib xyaw.
Lub geometry ntawm cov pwm kuj yog ib qho kev txiav txim siab: nyias-walled qhov chaw yuav tsum tau txhaj tshuaj ceev tshaj plaws; tuab-walled qhov chaw xav tau ib qho qeeb-ceev-ceev ceev nkhaus kom tsis txhob muaj qhov tsis xws luag; Txhawm rau kom ntseeg tau tias qhov ua tau zoo ua tau raws li tus qauv, kev txhaj tshuaj nrawm yuav tsum tau teeb tsa kom ntseeg tau tias cov yaj pem hauv ntej ntws mus tas li.
Lub melt flow rate yog ib qho tseem ceeb heev vim hais tias nws yuav cuam tshuam rau lub molecular kev taw qhia thiab nto lub xeev nyob rau hauv ib feem; thaum lub melt pem hauv ntej mus txog tus ntoo khaub lig qauv, nws yuav tsum tau qeeb; rau cov pwm nyuaj nrog radial diffusion, cov yaj dhau los yuav tsum tau lees tias nce tusyees; Cov neeg khiav dej num ntev yuav tsum tau ua kom tiav sai kom txo cov cua txias ntawm cov yaj hauv pem hauv ntej, tab sis kev txhaj tshuaj ntawm cov khoom siv high-viscosity, xws li PC, yog qhov tshwj xeeb, vim tias ceev ceev yuav coj cov khoom txias rau hauv kab noj hniav los ntawm cov dej nkag.
Kho qhov kev txhaj tshuaj nrawm tuaj yeem pab tshem tawm cov teeb meem tshwm sim los ntawm kev khiav qeeb ntawm cov dej nkag. Thaum cov yaj mus txog cov dej nkag los ntawm lub nozzle thiab tus khiav, qhov saum npoo ntawm cov yaj pem hauv ntej yuav tau txias thiab khov, los yog cov yaj stagnates vim qhov nqaim ntawm tus khiav mus txog thaum txaus siab los thawb lub yaj los ntawm qhov nkag. . Cov dej inlet, uas ua rau lub siab peaking los ntawm cov dej inlet.
Kev kub siab yuav ua rau cov khoom puas tsuaj thiab ua rau muaj qhov tsis xws luag xws li cov cim ntws thiab cov dej nkag, uas tuaj yeem kov yeej los ntawm decelerating ua ntej qhov nkag. Qhov no deceleration tiv thaiv ntau shear ntawm inlet theem ua ntej nce tus nqi hluav taws kub rau nws tus nqi qub. Vim tias nws yog qhov nyuaj heev rau kev tswj hwm tus nqi hluav taws xob kom qeeb ntawm cov dej inlet, nws yog ib qho kev daws teeb meem zoo dua kom qeeb ntawm qhov kawg ntawm tus khiav.
Peb tuaj yeem zam lossis txo qhov tsis xws luag xws li flash, burnt, ntxiab cua, thiab lwm yam los ntawm kev tswj qhov kawg txhaj tshuaj ceev. Deceleration ntawm qhov kawg ntawm filling tiv thaiv overfilling ntawm kab noj hniav, tsis txhob flashing thiab txo cov seem seem. Cov huab cua uas tshwm sim los ntawm cov pa tsis zoo ntawm qhov kawg ntawm cov pwm ntws los yog cov teeb meem txhaws tuaj yeem daws tau los ntawm kev txo cov pa tawm, tshwj xeeb tshaj yog thaum kawg ntawm kev txhaj tshuaj.
Qhov kev txhaj tshuaj luv luv yog tshwm sim los ntawm qhov qeeb qeeb ntawm cov dej nkag los yog qhov cuam tshuam ib nrab ntws los ntawm kev ua kom khov ntawm cov yaj. Kev nrawm nrawm ntawm kev txhaj tshuaj tsuas yog dhau los ntawm cov dej nkag lossis cov dej ntws hauv zos tuaj yeem daws qhov teeb meem no.
Cov teeb meem xws li cov cim ntws, cov dej ntws tawm, cov dej tawg, molecular breakage, delamination, thiab tev tawm uas tshwm sim ntawm cov ntaub ntawv kub-rhiab yog tshwm sim los ntawm cov shear ntau dhau thaum hla dej nkag.
Qhov chaw du yog nyob ntawm kev txhaj tshuaj nrawm, thiab cov khoom siv iav fiber ntau yog qhov tshwj xeeb, tshwj xeeb tshaj yog nylon. Cov chaw tsaus nti (wavy kab) yog tshwm sim los ntawm cov dej tsis ruaj khov vim qhov hloov pauv viscosity. Distorted flow tuaj yeem ua rau wavy lossis tsis zoo li haze, nyob ntawm seb qhov dej tsis ruaj khov.
Thaum cov yaj dhau los ntawm cov dej nkag, kev txhaj tshuaj nrawm yuav ua rau siab shear, thiab cov yas kub-rhiab yuav raug hlawv. Cov khoom siv charred no yuav dhau los ntawm cov kab noj hniav, ncav cuag qhov ntws hauv ntej, thiab tshwm rau ntawm qhov chaw.
Txhawm rau tiv thaiv kev txhaj tshuaj streaking, kev txhaj tshuaj nrawm yuav tsum tau teeb tsa kom qhov chaw khiav tau puv sai thiab tom qab ntawd maj mam dhau los ntawm qhov nkag. Nrhiav qhov kev hloov pauv ceev no yog qhov tseem ceeb ntawm qhov teeb meem. Yog tias nws ntxov dhau lawm, lub sijhawm sau yuav nce ntau dhau, yog tias nws lig dhau lawm, cov dej ntws ntau dhau yuav ua rau cov tsos ntawm cov dav hlau streaks. Qhov qis dua cov yaj viscosity thiab siab dua lub thoob qhov kub, qhov pom tseeb dua qhov nyiam ntawm cov qauv txhaj tshuaj no tshwm sim. Txij li thaum cov dej me me yuav tsum tau txhaj tshuaj kom ceev thiab siab, nws kuj yog ib qho tseem ceeb uas ua rau cov dej tsis zoo.
Shrinkage tuaj yeem txhim kho nrog kev hloov pauv siab dua, kev poob qis dua. Tsawg pwm kub thiab qeeb ntsia hlau ua ntej nrawm heev ua rau lub sijhawm ntev, uas yuav tsum tau them nyiaj los ntawm kev tua hluav taws kub. High-speed flow yuav txo tau cov cua sov, thiab kev sib txhuam ntawm cov cua sov vim yog siab shear tshav kub tuaj yeem ua rau qhov kub thiab txias tuaj yeem ua rau lub thickening ntawm cov txheej txheej sab nraud. Qhov kev sib tshuam ntawm kab noj hniav yuav tsum yog tuab txaus kom tsis txhob poob siab ntau dhau, txwv tsis pub shrinkage yuav tshwm sim.
Hauv luv luv, feem ntau cov kev txhaj tshuaj tsis raug tuaj yeem daws tau los ntawm kev kho qhov kev txhaj tshuaj nrawm, yog li qhov ua kom yuam kev los kho cov txheej txheem txhaj tshuaj molding yog los teeb tsa qhov kev txhaj tshuaj nrawm thiab nws ntu kom tsim nyog.
