Ib qho ntawm cov xwm txheej yooj yim rau kev ua haujlwm ntawm ib qhoelectromagnetic flowmeteryog tias qhov ib txwm muaj tam sim no hauv phab ntsa sab hauv ntawm lub raj ntsuas yog xoom tshwj tsis yog rau cov electrode. Txhawm rau ua tau raws li qhov xwm txheej no, txoj hauv kev yooj yim tshaj plaws yog kab sab hauv phab ntsa thiab lub ntsej muag flange kawg ntawm lub ntsej muag hlau ntsuas raj nrog insulating ntaub. Hauv txheej txheej' s cov lus, kev siv cov rwb thaiv tsev yog txhawm rau tiv thaiv qhov hluav taws xob ua kom muaj hluav taws xob los ntawm kev luv-ncig los ntawm cov yeeb nkab hlau. Nws tuaj yeem pom tau tias cov kab thaiv insulating ua lub luag haujlwm tseem ceeb hauv kev siv hluav taws xob ntsuas hluav taws xob. Yog li ntawd, hauv keeb kwm kev txhim kho hluav taws xob hluav taws xob ntsuas hluav taws xob, daim ntawv thov cov ntaub ntawv hauv ob sab thiab kev txhim kho txuas ntxiv ntawm txheej txheej txheej txheej tsim tshuab kuj tau koom nrog.
Muaj ntau hom kua dej hauv qhov ntsuas ntsuas tau zoo, thiab lawv lub cev thiab tshuaj lom neeg tsis zoo ib yam. Nws tsis yooj yim sua kom siv hom insulating khoom hauv ob sab phlu kom tau raws li lub cev thiab tshuaj muaj zog ntawm txhua daim ntawv thov ntawmelectromagnetic flowmeters. Cov kev xav tau no tau tshwm sim hauv qhov yuav tsum tau ntawm nruab nrab' qhov kub tsis kam, thermal poob siab, siab siab, tsis zoo, puas, puas, corrosion tsis kam, adhesion, adhesion thiab lwm yam hauv ob sab phlu. Hloov pauv, nws yog qhov tseeb vim tias lub raj ntsuas muaj ntau yam khoom siv sab hauv uas tuaj yeem hloov kho lub cev thiab tshuaj yam ntxwv ntawm cov kua nruab nrab, uas ua rau daim ntawv thov ntau ntawm cov tshuab hluav taws xob sib nqus ntsuas hluav taws xob dav dua.
Electromagnetic flowmeterstau siv los ntsuas cov raj nrog cov ntaub ntawv xws li polytetrafluoroethylene, roj hmab, polyvinyl chloride, polyurethane roj hmab, kev lag luam ceramics, thiab lwm yam. Cov yam ntxwv tseem ceeb ua haujlwm thiab txheej txheem txheej txheem ntawm cov ntaub ntawv txheej txheej no tau qhia luv luv hauv qab no.
1) Cov khoom siv hauv tsev tau siv ua cov khoom siv rauelectromagnetic flowmeters
Xyoo 1980s, cov khoom lag luam muaj cov khoom ua los ntawm cov khoom siv ua kom zoo nkauj txhuas oxide tau pib siv hauv cov raj ntsuas ntawm cov tshuab hluav taws xob sib nqus. Kev lag luam ceramics yog tsim los ntawm kev sib xyaw 996% mus rau 99.9% ntawm qhov khoob.
Cov khoom lag luam ceramic muaj cov rigidity siab dua thiab cov khoom siv dag zog ntau dua li fluoroplastics, roj hmab thiab polyurethane roj hmab txheej, thiab muaj cua sov zoo tiv thaiv, hnav tsis kam thiab tiv taus xeb, thiab lawv cov khoom siv hluav taws xob rwb thaiv tsev kuj zoo heev. Yuav luag tsis muaj kev hloov pauv hauv qhov kub thiab txias siab, yog li qhov ruaj khov. Kev ntsuas cua sov ua kom puas tsuaj ua pov thawj tias cov txheej txheem sintering siab tuaj yeem lav tau ntau yam ntawm cov cua sov ua haujlwm tsis kam ntawm cov khoom lag luam ntsuas lub raj. Lub zog ntawm cov khoom lag luam muaj ntau heev uas nws nyuaj rau rov ua dua lub raj ntsuas sintered los ntawm kev txiav cov txheej txheem. Nws hnav tsis kam yog ntau dua 10 npaug siab dua li cov roj hmab polyurethane. Kev tiv thaiv corrosion ntawm cov khoom lag luam ceramics yog nyob ntawm hom thiab kev coj dawb huv ntawm cov khoom siv. Piv txwv li, tib qhov kev coj dawb huv yog 99.7% thiab 99.9%, thiab kev tiv thaiv kev txhim kho corrosion ntawm kev coj dawb huv sib txawv yog txawv heev.
Kev ntsuas lub raj siv cov khoom siv hluav taws xob tuaj yeem siv cermet sib xyaw nrog cov hmoov platinum thiab alumina los ua cov qauv hluav taws xob yam tsis muaj qhov sib khi, yog li yuav tsis muaj qhov xau ntawm cov electrode, tsis muaj kua tuav thiab nkag mus. Ib feem ntawm cov hluav taws xob thiab cov phab ntsa sab hauv ntawm lub raj ntsuas muaj qhov loj me thiab zoo ib yam nkaus, qhov sib txhuam coefficient thaum cov dej slurry ntws los ntawm qhov me me, qhov tsawg zaus polarization voltage uas zoo nkaus li tsawg heev, thiab cov ntsuas tso tawm tau ruaj khov . Kev txhim kho cov ntaub ntawv no thiab txheej txheem yog ib qho tseem ceeb heev los daws qhov kev ntseeg tau thiab kev txhim kho corrosion ntawm electromagnetic flowmeter, thiab nws zoo heev. Qhov kub sintering ntawm high-purity alumina ceramics yog siab heev, kwv yees li 1800 ° C, uas tau tshaj qhov melting point ntawm cov hlau acid-resistant hlau. Yog li ntawd, lub sijhawm tswj hwm thiab txheej txheem txheej txheem cua sov, kev txuag hluav taws xob thiab cua txias hauv cov txheej txheem sintering cuam tshuam ncaj qha rau cov khoom lag luam zoo. Hauv ntej, cov khoom siv hauv tsev yog cov khoom siv hauv zos zoo tshaj plaws. Txawm li cas los xij, vim yog cov txheej txheem tsim khoom nyuaj thiab cov txheej txheem nyuaj, tam sim no kev lag luam tsim hluav taws xob hluav taws xob hluav taws xob hluav taws xob hluav taws xob tseem tsis tau tsim, thiab cov tebchaws txawv teb chaws tuaj yeem ua tiav txoj kab ntsuas kab hauv qab DN200.
2) Polyurethane roj hmab tau siv ua cov khoom siv sab hauvelectromagnetic flowmeter
Polyurethane roj hmab yog tsim los ntawm kev hloov pauv polymer (poly lossis poly) thiab diisocyanate sib xyaw. Nws cov qauv tshuaj lom neeg yog qhov nyuaj dua li ntawm cov khoom siv dav dav polymers. Ntxiv rau cov pab pawg carbamate rov tshwm sim, cov saw hlau feem ntau muaj cov pab pawg xws li radicals, pab pawg phenylene, thiab pab pawg uas muaj ntxhiab. Cov saw tseem ceeb ntawm UR cov txheej txheem yog tsim los ntawm cov ntu mos thiab tawv ua ntu: ntu ntu kuj tseem hu ua ntu ntu, uas yog tsim los ntawm oligomer polyols (xws li poly, polytuning, polybutadiene, thiab lwm yam): ntu ntu kuj tseem muaj hu ua Cov ntu nyuaj yog tsim los ntawm cov tshuaj tiv thaiv cov khoom ntawm diisochlorate (xws li TDI MDI, thiab lwm yam) thiab cov saw me me txuas ntxiv (xws li diamines thiab glycols, thiab lwm yam). Kev faib ua feem ntawm cov ntu muag muag yog ntau dua ntawm cov ntu nyuaj. Lub polarity ntawm ntu mos thiab tawv sib txawv. Cov tawv tawv muaj qhov sib txawv muaj zog thiab yooj yim los sib sau ua ke los tsim ntau qhov kev faib me me hauv ntu ntu muag. Qhov no hu ua microphase cais qauv. Nws lub cev thiab cov khoom siv dag zog Qib ntawm kev sib cais theem muaj ntau yam ua nrog.
3) Roj hmab tau siv los ua cov khoom siv sab hauvelectromagnetic flowmeter
Roj hmab yog ib qho ntawm cov khoom siv feem ntau siv rau cov khoom siv hluav taws xob sib nqus. Nws tau siv hauv kev ntsuas dej, dej phwj tuaj, thiab cov kua qaub tsis muaj zog thiab cov kua dej tsis muaj zog ntawm chav sov, thiab nws qhov kev siv yog qhov loj. Hom roj hmab muaj xws li roj hmab ntuj, neoprene, roj hmab nitrile, thiab lwm yam. Chloroprene roj hmab yog ua los ntawm chloroprene ua cov khoom siv tseem ceeb los ntawm homopolymerization lossis copolymerization ntawm me me ntawm lwm cov monomers. Xws li lub zog tensile siab, tiv tshav kub, tiv taus lub teeb, laus tiv taus, thiab roj tsis kam yog qhov zoo dua roj hmab ntuj, styrene butadiene roj hmab, butadiene roj hmab. Nws muaj cov nplaim hluav taws tiv taus thiab nplaim hluav taws kub zoo, muaj tshuaj ruaj khov, thiab tiv taus dej zoo. Qhov tsis zoo ntawm neoprene yog hluav taws xob rwb thaiv tsev
Yog, qhov ua haujlwm txias tsis zoo, thiab cov roj hmab nyoos tsis ruaj khov thaum khaws cia. Neoprene muaj ntau yam kev siv, xws li kev tsim cov tsheb thauj mus los thiab cov menyuam xa mus, cov ntaub npog npog ntawm cov xov hlau thiab cov xov hluav taws xob, kev tsim cov roj-resistant hoses, gaskets, thiab cov khoom siv tshuaj tiv taus cov ntoo. Ntawm cov tshuaj fluoroplastics siv uaelectromagnetic flowmeters, feem ntau muaj PTFE, FEP, E-TEE thiab PFA. Ntawm cov tshuaj fluoroplastics ntawm no, PTFE muaj cov tshuaj zoo tshaj plaws ruaj khov. Txawm li cas los xij, nws nyuaj rau sib txuas PTFE thiab cov hlau tsis xeb ntsuas raj. Txawm hais tias txheej txheem kev sib txuas ntawm PTFE thiab cov kua qaub-resistant hlau ntsuas raj tau tawg, cov kab hauv qee yam khoom tseem nyob ze nrog cov kua qaub-resistant hlau ntsuas raj. Yog li, nws yuav tsum tau them sai sai rau qhov ntsuas kub thiab hloov pauv ntawm cov kua thaum siv. Qhov ntsuas kub kub los ntawm qhov tsis zoo thiab cua sov yuav yooj yim ua rau lub hauv paus raug cais los ntawm lub raj ntsuas, tev tawm, thiab tawg, uas yuav ua rau lub tshuab hluav taws xob foob kom xau thiab ua rau cov cuab yeej tso tawm tsis ua haujlwm. Ruaj, txawm puas.
Lwm yam yas uas me dua li PTFE hauv kev tiv thaiv kev xeb, tab sis lawv txhua tus tuaj yeem txhaj tshuaj los yog yas, thiab txais kev ntsuas xws li ntxiv cov hlau tsis xeb hlau ntxaij lossis hlau tsis xeb ntsuas raj sab hauv phab ntsa thiab flange kawg lub ntsej muag kom dovetail zawj, thiab lwm yam ., thiab txhaj tshuaj molded fluoroplastics ua ke nrog nws. Nws yog khov thiab tuaj yeem daws qhov teeb meem ntawm cov kua dej poob siab thiab qhov siab tsis zoo.