1. Ua kom muaj txiaj ntsig zoo ntawm cov khoom thauj thiab Melting
Khoom Muag Khoom: Cov seem pub ntawm cov ntsia hlau conveys PPR pellets (cov khoom siv) nkag los ntawm lub hopper rau pem hauv ntej thiab maj mam compacts lawv. Lub geometric tsis ntawm cov ntsia hlau (xws li zawj qhov tob thiab helix lub kaum sab xis) ncaj qha txiav txim siab qhov kev ua haujlwm zoo.
Forced Melting: PPR yog crystalline polymer nrog qhov sib txawv melting point (kwv yees li 140-160 degree). Los ntawm kev sib hloov ntawm cov ntsia hlau thiab cov cua sov sab nraud, cov khoom siv tau hnyav shearing, kev sib txhuam, thiab compression nyob rau hauv lub compression cheeb tsam, tsim ib tug ruaj khov yaj. Cov ntsia hlau compression piv tus qauv tsim (qhov piv ntawm cov khoom noj seem zawj qhov tob rau qhov ntsuas qhov tob tob) yog qhov tseem ceeb tshwj xeeb tshaj yog - qhov tsim nyog compression piv (feem ntau yog 2.5-3.5 rau PPR) ua kom tiav thiab zoo ib yam melting ntawm PPR pellets, tiv thaiv kev tsim ntawm unmelted "ntses ob lub qhov muag" los yog crystalline me ntsis.
Txhais nrog DeepL.com (dawb version)
2. Muab kev sib xyaw kom txaus thiab homogenization
PPR cov ntaub ntawv yuav tsum tau ntxiv cov khoom tsim nyog (xws li antioxidants thiab xim masterbatches), thiab lawv qhov hnyav molecular faib cuam tshuam rau lawv cov kev ua tau zoo. Cov ntsia hlau tsim ua tiav homogenization los ntawm cov hauv qab no:
Distribution mixing: Uniformly dispersing additives and colour masterbatches thoob plaws hauv lub yaj kom tsis txhob muaj xim txawv los yog additive agglomeration.
Dispersive mixing: Ua kom muaj zog shear siab los ntawm cov ntsia hlau tshwj xeeb (xws li cov ntu ntu, cov pins, thiab cov khoom sib xyaw) txhawm rau txhawm rau agglomerated additives thiab disperse lawv uniformly, thaum tib lub sij hawm txhawb kev taw qhia thiab rearrangement ntawm PPR molecular chains los txhim kho yaj lub zog.
Kub homogenization: Txo qhov kub ntawm qhov sib txawv ntawm cov yaj hauv ob qho tib si ncig thiab axial cov lus qhia (feem ntau tswj tsis pub dhau ± 1-2 degree), tiv thaiv cov khoom degradation tshwm sim los ntawm lub zos overheating los yog nyuaj rau extrusion los ntawm localized undercooling.
3. Tsim kom muaj kev ruaj khov thiab tswj tau lub siab melting
Tsim lub siab rov qab: Cov metering seem ntawm cov ntsia hlau, los ntawm cov groove qhov tob thiab qhov ntev, tsim kom txaus siab ntawm qhov tuag (PPR yeeb nkab extrusion feem ntau yuav tsum tau 15-30 MPa). Lub siab no yog tsim nyog los kov yeej kev tiv thaiv los ntawm kev tuag, lim tshuaj ntsuam, thiab pwm, kom ntseeg tau tias cov yaj sau cov pwm ntom ntom thiab tsis tu ncua.
Kev Tiv Thaiv Kev Ruaj Ntseg: Lub siab ruaj khov yog qhov tseem ceeb los ua kom cov yeeb nkab tsis sib xws sab nraud thiab phab ntsa tuab. High-kev ua tau zoo ntsia hlau tsim (xws li phua screws thiab BM-hom screws) tuaj yeem txo qhov siab ntawm pulsations, feem ntau ua kom muaj kev hloov pauv hauv ± 1%.
4. Kev kho kom haum rau lub cim Rheological Properties ntawm PPR Khoom
PPR yaj nthuav tawm kev coj tus cwj pwm thinning (piv txwv li, viscosity txo qis thaum shear tus nqi nce) thiab qhov dav ntawm qhov hnyav molecular faib. Targeted screw designs muaj xws li:
Kev sib piv qis qis: qis dua li ntawm PE lossis PPH, txhawm rau tiv thaiv cov shear ntau dhau los ua rau PPR molecular saw tawg lossis degradation.
Ntev melting thiab metering zones: Kom haum rau PPR qhov dav melting kub ntau yam, xyuas kom txaus plasticization thaum tiv thaiv yellowing tshwm sim los ntawm lub tshav kub ntev.
Qhov ntev npaum li cas - rau - txoj kab uas hla (L/D): PPR yeeb nkab extrusion feem ntau siv L/D piv ntawm 30: 1 txog 36: 1. Qhov sib piv L/D txaus ua kom qis - qhov kub thiab txias extrusion (txo cov kev ntxhov siab sab hauv) thiab cov zis siab, tab sis qhov sib piv ntev heev tuaj yeem ua rau cov khoom siv degradation.
5. Ntsuas cov zis thiab kev siv hluav taws xob
Geometric qhov ntev txiav txim siab theoretical conveying muaj peev xwm: tsis xws li ntsia hlau zawj qhov tob, suab, thiab lub hauv paus txoj kab uas hla sib sau ua ke txiav txim siab ntim ntawm yaj uas tuaj yeem xa mus rau ib chav tsev ntawm lub sijhawm. Sib sib zog nqus grooves nce tso zis tab sis txi nws efficiency; ntiav grooves muaj qhov opposite nyhuv.
Optimizing Power Efficiency: Ib qho zoo heev ntsia hlau tsim kom ntseeg tau tias, thaum tuav cov yas zoo, ntau dua ntawm lub cev muaj zog lub zog nkag mus rau hauv cov khoom siv lub zog sab hauv thiab lub zog siab, es tsis txhob nkim ntawm kev sib txhuam tsis zoo lossis rov qab. Feem ntau, siab -cov ntsia hlau ua tau zoo tuaj yeem txo qis kev siv hluav taws xob los ntawm 15-25%.