Tau ntau xyoo, fluoropolymers tau ua lub luag haujlwm tseem ceeb hauv kev lag luam tshuaj thiab cov khoom lag luam zoo sib xws los tiv thaiv cov nroj tsuag thiab cov cuab yeej siv tshuaj tua kab mob los ntawm ntau yam kev tawm tsam.Qhov no yog vim tias lawv muaj cov tshuaj tiv thaiv zoo thiab thermal stability ntau dua li lwm cov khoom yas los yog elastomeric.Rau ntau xyoo fluoropolymers tau ua lub luag haujlwm tseem ceeb hauv kev lag luam chemical thiab zoo sib xws los tiv thaiv cov nroj tsuag thiab cov cuab yeej tiv thaiv tshuaj tua kab mob los ntawm ntau yam kev txhoj puab heev. xov xwm.Qhov no yog vim hais tias lawv muaj cov tshuaj tiv thaiv zoo thiab thermal stability ntau dua li lwm cov khoom yas los yog elastomeric.
Tom qab kev txhim kho ntawm PTFE, qhov kev taw qhia ntawm melt-processable fluorinated ethylene-propylene (FEP) nyob rau hauv 1960 tau qhib tag nrho cov ntaub ntawv tshiab.PFA, perfluoro-alkoxy polymer uas tau siv tau zoo rau 20 xyoo ua cov khoom siv hauv ob sab phlu, tam sim no yog cov thermoplastic successor rau PTFE, nrog sib npaug thermal thiab tshuaj tiv thaiv thiab superior zog hais txog kev ua tau zoo, translucency, permeation resistance thiab mechanical zog. .
Hauv kev lag luam tshuaj, ob qho tib si fluoropolymer - PTFE thiab PFA - yog siv feem ntau hauv cov ntaub hauv ob sab phlu.Rau cov duab yooj yim, xws li cov kav dej, khoov, T-thooj lossis txo cov pob qij txha, PTFE feem ntau yog siv;Nws yog siv los ntawm kev muab tshuaj txhuam extrusion, ram extrusion los yog daim kab xev cua-ing.Hauv cov txheej txheem no, daim ntawv ua ntej yog ua los ntawm PTFE;Qhov no yog ces sintered thiab tso rau hauv cov hlau workpiece.Siv PTFE rau hauv ob sab phlu ntawm cov hlau qhov chaw ntawm cov duab nyuaj, xws li li qub thiab cov twj, yog qhov nyuaj dua.Isostatic molding yog ces txoj kev nyiam.Hauv no PTFE hmoov yog ntim rau hauv qhov chaw tsim ntawm cov hlau ua haujlwm-thooj thiab ib lub hnab roj hmab uas tau tsim tshwj xeeb kom haum rau hauv cov duab ntawm qhov chaw yuav tsum tau lined.Cov hmoov yog pre-compressed, ces txias-nias rau hauv cov duab xav tau.Thaum kawg, lub hnab roj hmab raug tshem tawm thiab cov kab hauv kab yog sintered nyob rau hauv qhov cub ntawm 360?C (680?F).
PFA, cov khoom siv thermoplastic nrog lub ntsiab lus melting zoo, tuaj yeem ua tiav los ntawm kev hloov pauv lossis txhaj tshuaj molding.Cov granulate yog yaj nyob rau hauv lub lauj kaub yaj los yog nyob rau hauv lub extruder thiab ces yuam mus rau hauv lub kub lub cuab tam los ntawm ib tug hydraulic xovxwm.
Txoj kev no ua kom cov phab ntsa-thicknesses ua tiav, nrog rau kev ua siab ntev?0.5 hli, txawm nyob rau hauv nruj radii thiab undercuts.Xyaum tsis xav tau txhua yam khoom tiav, tsuas yog tshem tawm cov sprue thiab ua kom du lub ntsej muag ntawm flanges.
Thaum siv isostatic molding, txawm li cas los xij, xav tau ntau npaum li cas ntawm cov tshuab ua tiav - nyob ntawm seb qhov teeb meem ntawm cov duab yuav tsum tau ua kom tiav - kom ua tiav qhov kev xav tau nrog qhov tseeb.
Qhov sib npaug ntawm cov phab ntsa-thickness yuav txawv dua, tshwj xeeb tshaj yog nyob rau hauv cov ntaub ntawv ntawm ntau cov duab nyuaj xws li valve tsev.
Absorption thiab permeation
Tsis zoo li cov hlau, yas thiab elastomers nqus cov xov xwm sib txawv uas lawv tuaj yeem sib cuag.Qhov no feem ntau yog cov ntaub ntawv nrog cov organic tebchaw.Kev nqus tuaj yeem ua raws li permeation los ntawm phab ntsa hauv ob sab phlu.Txawm hais tias qhov no tsis tshua pom nrog fluoropolymer, nws tuaj yeem cuam tshuam los ntawm kev nce phab ntsa-thickness lossis los ntawm kev txhim kho cov cuab yeej siv kom tshem tawm qhov chaw ntawm fluoropolymer hauv ob sab phlu thiab cov phab ntsa hlau.Nws tau pom meej meej tias nyob rau hauv kev hwm ntawm permeation thiab nqus, yaj-ua cov fluoropolymers xws li PFA qhia zoo barrier zog dua PTFE.
Vacuum Resistance
Lub tshuab nqus tsev yog xav tau vim hais tias, nyob rau hauv kaw systems ntawm hom dav siv nyob rau hauv tshuaj ua, ib tug poob nyob rau hauv qhov kub thiab txias tsim lub nqus tsev vacuum nyob rau hauv lub system, tshwj tsis yog tias nws twb ua hauj lwm hauv qab atmospheric siab.Thaum siv PFA nws yog qhov yooj yim kom ua tiav lub tshuab nqus tsev txaus rau hauv ob sab phlu.Feem ntau cov hauv ob sab phlu yog ?anchored?mus rau phab ntsa hlau los ntawm txhais tau tias ntawm ?dov-tail?grooves los yog channels
tom qab.
Nrog PTFE granulate uas tau txias-tsim, nws yog qhov nyuaj dua kom ua tiav lub suab nrov ntawm cov hauv ob sab phlu hauv cov phab ntsa hlau raws li cov kab loj loj yuav xav tau kom tso cai rau PTFE hmoov ntws mus rau hauv cov grooves.Feem ntau, yog li ntawd, cov khoom sib txuas yog siv ntawm PTFE hauv ob sab phlu thiab cov vaj tsev hlau.Txawm li cas los xij, vim muaj cov yam ntxwv ntawm cov nplaum nplaum ntawm fluoropolymer thiab cov thermal tsis kam ntawm cov khoom sib txuas, PTFE qhia tsuas yog txwv lub tshuab nqus tsev.
Kev Tswj Xyuas Zoo tiv thaiv kev tawg thiab Voids
Nrog PTFE thiab PFA hauv ob sab phlu, lub zog dielectric yog ntsuas txhawm rau txheeb xyuas qhov tsis raug.Txoj kev no txhim khu kev qha cov kab nrib pleb thiab voids uas mus tag nrho txoj hauv kev los ntawm cov khoom siv tab sis, vim muaj kev paub zoo ntawm cov fluoropolymers, nws tsis qhia tias muaj qhov tsis zoo uas pib 1,5 hli lossis ntau dua hauv qab (daim duab 5) .
Vim li no ntxiv kev ntsuam xyuas siv txoj kev ultrasonic kuj tuaj yeem siv tau.Qhov kev ntsuas no ntsuas qhov kev ncua deb ntawm qhov chaw ntawm lub hauv ob sab phlu mus rau lub vaj tsev hlau.Txawm li cas los xij, nws tsis ntseeg tau vim tias nws tsis muab qhov tseeb hauv ob sab phlu thaum muaj qhov khoob lossis qhov porosity.Tsis tas li ntawd, txoj kev no yog qhov tsis zoo rau kev ua haujlwm ntawm cov khoom me me lossis cov duab nyuaj me me nrog cov undercuts thiab nruj radii.
Lwm txoj hauv kev los kuaj xyuas qhov tsis xws luag xws li cov kab nrib pleb thiab voids yog nrog lub npe hu ua ?Met-L-Check?dye penetrant method.Tab sis txoj kev no tsuas yog txwv rau kev kuaj xyuas qhov tsis xws luag xwb.
Chemical Structure
PFA, uas yog translucent, tuaj yeem ntseeg tau los kuaj xyuas qhov muag pom.Cov kab nrib pleb thiab voids nyob rau hauv qhov chaw tuaj yeem pom nrog cov teeb pom kev zoo.Tsis tshua muaj kev nkag mus rau hauv cov ntaub ntawv tuaj yeem kuaj xyuas siv cov teeb txias txias thiab cov kev taw qhia hloov tau yooj yim fiber ntau.
Cov nqi sib piv rau cov hlua
Hais txog tus nqi raw khoom, PFA tus nqi kwv yees li peb zaug ntau npaum li PTFE.
Txawm li cas los xij, qhov tsis zoo no tuaj yeem raug them los yog txo qis heev, raws li kev ua haujlwm ntawm cov yam ntxwv xws li cov duab yuav tsum tau lined, nws qhov loj, tus naj npawb ntawm workpieces yuav tsum tau lined thiab cov txheej txheem kev saws.Qhov no ua tau vim tias PFA tsis tas yuav tsum tau npaj cov txheej txheem los yog ua tiav machining nrog cov khoom siv poob.
Kev siv PFA rau hauv ob sab phlu loj heev tsis pom zoo, vim hais tias cov khoom siv siab yuav ua rau cov khoom kim heev.Lwm qhov tseem ceeb uas yuav tsum nco ntsoov yog tus nqi ntawm cov cuab yeej, uas tsis yog amortized
thaum tsuas yog qee qhov me me ntawm qhov yuav tsum tau ua kab.Tsis tas li ntawd, muaj cov tswv yim txwv rau qhov hnyav ntawm cov khoom txhaj tshuaj uas cov tshuab molding muaj peev xwm tuav tau.
Cov lus xaus
Ntau tshaj 20 xyoo ntawm kev paub nrog cov hlua rau ntau qhov chaw, xws li lub valve thiab lub twj tso kua mis, tau pom tias PFA muaj ntau qhov zoo thaum muaj cua sov thiab tshuaj tiv thaiv yog qhov tseem ceeb.
Qhov tseeb thiab txawm tias phab ntsa-thickness tuaj yeem ua tiav nrog PFA yog qhov zoo dua qub, tshwj xeeb tshaj yog thaum ua haujlwm nrog cov xov xwm uas muaj lub zog muaj zog rau diffuse.
Kev ua tau zoo kuj tau qhia tias PFA muab cov khoom thaiv zoo dua li PTFE.
Bromine manufacturers qhia, piv txwv li, hais tias qhov tob tob ntawm bromine nyob rau hauv PFA yog ib feem peb tsawg tshaj li nyob rau hauv PTFE, thaum ua hauj lwm tej yam kev mob xws li lub sij hawm, kub thiab siab yog tib yam.
PTFE, ntawm qhov tod tes, tseem siv dav rau cov khoom siv tshuaj lom neeg thiab lwm yam khoom siv tshuaj ua haujlwm uas yuav tsum tau ua kom qaug zog ua haujlwm.
Cov piv txwv ntawm cov ntawv thov no yog cov hauv qab, nrog rau cov diaphragms hauv li qub thiab cov twj tso kua mis.
Rau lub rooj zaum rings, plugs, ntsaws ruaj ruaj thiab cov khoom zoo sib xws, PTFE yog cov khoom tsim nyog thiab kev lag luam.
Ib qho kev sib txawv tsis ntev los no rau cov khoom xws li cov no yog siv hloov kho PTFE, vim nws qhov ruaj khov thiab qhov tawv tawv zoo dua rau cov qauv PTFE.
Hot Tags: PTFE vs PFA
Post lub sij hawm: Apr-01-2017