Dab tsi yog qhov Critical Sheath Thickness rau 316 Stainless Steel Heating Tubes nyob rau hauv siab -Purity Deionized Dej ntawm 95-100 degree?

Qhov Kev Ua Lag Luam Tseem Ceeb hauv High-Kev Pabcuam Kev Tiv Thaiv

Qhov chaw corrosive ntawm 316 stainless hlau cua sov raj hauv siab -purity deionised (DI) dej, muaj ib tug resistivity> 1 MΩ·cm (feem ntau 10-18 MΩ·cm), yog ib tug contradiction. DI dej lub siab purity tshem tawm feem ntau cov txheej txheem electrochemical corrosion, tab sis qhov purity heev uas ua rau nws txaus nyiam ua rau corrosive ib puag ncig rau passive hlau. Yog hais tias cov conductivity tsis siab txaus kom tso cai rau txo cov pa oxygen los yog lwm yam kev cuam tshuam cathodic, cov txheej tiv thaiv chromium oxide yuav tsis ruaj khov thiab tej zaum yuav tsis muaj zog los yog hauv zos tawg. Qhov tshwm sim no tau nrawm dua ntawm qhov kub siab ze li 100 ° C. Sheath thickness yog ib qho tseem ceeb hauv kev tiv thaiv qhov tshwm sim ntawm qhov perforation ntawm no peculiar corrosion, thiab nyob rau hauv lub thermal efficiency tsim nyog los txhawb nqa cov txheej txheem kub hauv semiconductor ntxhua, tshuaj dej - rau - txhaj tshuaj (WFI) systems, thiab kuaj recirculating da dej. Qhov kev tshuaj ntsuam no txheeb xyuas qhov chaw pib thickness ntau yam uas qhov ua kom zoo dua corrosion me me hauv cov dej huv huv siab tsis cuam tshuam qhov kub ntawm cov phab ntsa tuab.

Corrosion Cwj Pwm hauv High Purity Deionised Dej.

316 stainless hlau tsis corrode nyob rau hauv siab -purity DI dej ntawm 95-100℃nyob rau hauv cov pa siab ntawm hlau poob vim oxidation. Es tsis txhob, qhov tseem ceeb degradation mechanism yog kev puas tsuaj ntawm passivity thiab tom qab ntawd maj mam sib xyaw leaching ntawm alloying ntsiab. Kev tshawb fawb ntawm stainless hlau nyob rau hauv siab - kub, siab -resistivity dej qhia corrosion tus nqi ntawm qhov kev txiav txim ntawm 0.005-0.02 mm / xyoo nrog hlau thiab chromium ions raug tso tawm mus rau hauv cov tshuaj ntawm qhov chaw -ib -billion theem. Nyob rau hauv cov txheej txheem no ib phab ntsa 1.0 hli tuab yuav hypothetically ciaj sia 50-200 xyoo. Qhov teeb meem tseem ceeb tshaj yog tsis yog qhov puncture, tab sis kev sib kis ntawm cov khoom. Raws li cov txheej txheem dhau mus zuj zus, cov hlau ions raug tso tawm rau hauv DI dej txo qis kev tiv thaiv thiab tej zaum tso rau ntawm cov khoom qis qis. Txawm tias ob peb feem ntawm ib lab ntawm cov hlau los yog chromium tuaj yeem ua rau cov khoom zoo hauv cov ntawv thov xws li kev ntxhua khaub ncaws semiconductor lossis kev tsim tshuaj. Thicker phab ntsa tsis txo tus nqi ntawm ion tso tawm ib chav tsev; Lub dissolving ntawm passive zaj duab xis yog ib tug nto tshwm sim thiab yog ywj siab ntawm lub thickness ntawm lub hauv paus tej. Txawm li cas los xij, cov phab ntsa tuab dua muaj qhov tso dej loj dua ntawm chromium los txhawb nqa cov txheej txheem dhau mus ntev dua. Tus nqi corrosion tuaj yeem nrawm nrawm heev thaum ze ntawm - thaj tsam saum npoo yog depleted ntawm chromium (hauv qab 16-18 % xav tau rau kev ua haujlwm ntev). Lub phab ntsa tuab tso cai rau cov khoom siv ntau dua ntawm chromium kom diffuse rau saum npoo thiab yog li ua rau lub xeev passive. Diffusion kwv yees qhia tau hais tias rau 316 stainless hlau raj ntawm 100 degree, chromium depletion cheeb tsam nkag mus nyob ib ncig ntawm 0.2-0.3 hli hauv qab ntawm qhov chaw tom qab tsib xyoos ntawm kev kis mus tas li. Ib phab ntsa tuab 1.0 hli yuav yog 70-80% tsis cuam tshuam rau hauv ntu ntu, 2.0 hli tuab phab ntsa 85-90% tsis cuam tshuam, qhov sib txawv me ntsis. Qhov kev tshawb pom tseem ceeb tshaj plaws yog tias rau cov dej purity siab, ua kom cov tuab tshaj li ~ 1.5 hli muab cov txiaj ntsig tsawg dua rau kev tiv thaiv corrosion.

Ultra ntshiab dej system thermal kev ua tau zoo yuav tsum

High -cov dej huv huv feem ntau yog khaws cia ntawm 80–95℃rau WFI loops lossis 25–60℃rau kev ua haujlwm semiconductor. Cov cua kub yuav tsum ua kom muaj kev ruaj ntseg ntawm qhov kub thiab txias, feem ntau nyob rau hauv ± 1 degree, thiab teb sai sai rau cov xwm txheej kos. Lub hnab hnyav dua muab kev tiv thaiv thermal ntau dua rau cov cua sov retard- nce thiab rov qab. Rau ib lub 316 stainless hlau raj nrog txheej kab 12 hli, tsa cov phab ntsa thickness ntawm 1.2 hli mus rau 2.0 hli tsub kom lub tshav kub tsis kam piv ln (ro / ri) ln (ro / ri) los ntawm 0.223 mus rau 0.405-ib 82% kev txhim kho. Qhov kev tiv thaiv thermal ntxiv no tuaj yeem ua rau qhov kub thiab txias (rau qhov txuas txuas ntxiv WFI lub voj voog ntawm 95℃nrog 2 kW rhaub) los ntawm 105℃mus rau 125 degree. Qhov nce ntawm 20℃no ua rau ob qho kev cuam tshuam tsis zoo. Ua ntej, nws nce qhov nrawm ntawm kev tawg ntawm cov yeeb yaj kiab passive. Arrhenius tus cwj pwm txhais tau hais tias kev sib cais kwv yees li ob npaug nrog txhua 15-20℃nce, yog li phab ntsa 2.0 hli yuav yog 2-3 zaug ntau dua corrosive dua li phab ntsa 1.2 hli vim tias qhov kub ua haujlwm ntau dua. Qhov thib ob, qhov kub ntawm qhov kub thiab txias tuaj yeem ua rau muaj qhov tshwm sim ntawm qhov kub ntawm qhov chaw ntawm lub raj nplaim uas tuaj yeem tsim cov npuas npuas uas ua rau muaj kev cuam tshuam loj heev rau kev hloov pauv ntawm tshav kub thiab ua rau muaj kev kub ntxhov. Rau siab purity daim ntaub ntawv, ib tug dav tsim qauv yog kom lub sheath kub hauv qab no 110℃kom tsis txhob boiling thiab ion tso tawm. Qhov kev txwv no zoo txwv qhov ua tau zoo tshaj plaws phab ntsa thickness. Rau 12 hli txheej txoj kab uas hla, phab ntsa tuab ntawm ib ncig ntawm 1.5-1.6 hli yog qhov siab tshaj plaws tso cai kom nyob qis dua 110℃rau 6 W / cm 2 hauv 95℃dej.

Scenario-Piv txwv ntawm High-Purity Deionised Water Selection Guide

Cov lus hauv qab no muab cov lus pom zoo tsawg kawg nkaus ntawm cov thickness rau 316 stainless hlau cua sov raj hauv cov dej purity siab nyob ntawm cov dej tsis kam, kev khiav hauj lwm kub thiab qhov purity rhiab heev ntawm cov dej ntws.

Kev khiav hauj lwm yam ntxwv & Purity Requirement Critical Wall Thickness Thermal & Corrosion Trade-offs Laboratory DI dej (1-5 MΩ·cm), 80-90 degree, intermittent use 1.2 mm Low corrosion rate. Sheath kub <105 degree. Nyias phab ntsa rau cua sov ceev -up. Standard sanitary tubing yog ok.
Pharmaceutical WFI (10-18 MΩ·cm), 90-95 degree, nruam recirculation, 5-xyoo lub neej 1.5 hli Critical thickness rau sheath kub tswj (tseem qis dua 110℃ntawm 5-6 W / cm^2). 1.0 mm suab hlau thiab ~ 0.25 mm chromium depletion xyoo tom qab
Semiconductor yaug (18 MΩ·cm,<1 ppb metal ions), 60-70 °C, ultra-sensitive 1.2-1.4 mm with electropolish Limit by ion release, not perforation The electropolished surface has lower surface area and passive film thickness. Thicker wall does not reduce ion flux. Thinner wall recommended for thermal control.
95-100 degree, 15-18 MΩ·cm Kub Kub DI Loop, 1.6-1.8 mm, 10-xyoo lub neej. Lub neej txuas ntxiv xav tau chromium reservoir . 1.6 hli yam tsawg kawg nkaus kom khaws qhov kub hauv qab 110℃ntawm qis watt ntom (4-5 W / cm2). Sab saum toj 1.8mm thermal txim yog phem tshaj qhov txiaj ntsig corrosion.
Txhua lub cev DI tau ntsib qhov chaw qhuav qhuav- tawm lossis nkag ntawm huab cua 2.0 hli Oxygen ingress thaum lub sijhawm saib xyuas tuaj yeem ua rau cov hlwb hauv cheeb tsam ntawm cov dej- huab cua cuam tshuam. Lub thickness ntxiv muab qhov kev nyab xeeb ntawm pitting. Cia siab tias cua sov- nce lub sijhawm 30-40% ntev dua.
Lwm cov qauv tsim uas tuaj nrog tuab

Phab ntsa thickness yog ib qho ntawm ob peb yam tseem ceeb sib npaug rau siab -cov dej huv huv. Ua ntej yog nto tiav: electropolishing rau Ra < 0.4 µm txo qhov chaw tiag tiag thiab cov khoom nkag tuaj yeem ua qhov chaw pib rau corrosion. Lub electropolished 1.2-mm phab ntsa feem ntau muab cov hlau ions tsawg dua li cov tshuab polished 2.0-mm phab ntsa. Thib ob, watt ceev tswj - txo qhov watt ntom ntom rau 4-5 W / cm² txwv lub plhaub- rau-dej kub qhov sib txawv hauv qab 12 degree, txo qis thermal stress thiab passive film dissolving. Qhov thib peb, ntws nrawm - turbulent flow (Re> 10,000) inhibits stagnation ntawm ciam teb txheej uas yaj cov hlau ions tuaj yeem tsim, tab sis tshaj tawm tshaj 2.5 m / s yuav tsum zam kom tsis txhob yaig ntawm cov zaj duab xis passive. Plaub, qhov system pre-passivation: ua haujlwm lub rhaub dej hauv DI dej ntawm 70-80℃rau 48-72 h ua ntej qhov kev pabcuam rhiab tso cai rau qhov ruaj khov, paub tab passive zaj duab xis rau daim ntawv, txo cov ion tso tawm tom qab los ntawm 50-70%. Thaum kawg, cov ntaub ntawv pov thawj - qhia cov pa roj carbon tsawg (316L) nrog cov ntsiab lus molybdenum validated (2.5-3.0%) thiab suav nrog ib daim ntawv ntsuam xyuas zeb ua kom tus cwj pwm tsis zoo.

Cov ntsiab lus tsim kom muaj qhov tseem ceeb Thickness rau High Purity Service

Lub thickness ntawm lub sheath ntawm 316 stainless hlau cua sov raj tau xaiv nyob rau hauv siab - purity deionised dej nyob rau hauv lub hauv paus uas lub limiting yam tsis yog tus nqi ntawm corrosion tab sis lub stability ntawm passive txheej thiab tso tawm ions. Lub thickness tseem ceeb yog qhov uas tswj cov sheath kub hauv qab 110℃thiab muaj txaus chromium reservoir kom muaj passivity thoob plaws hauv lub neej tsim. Rau feem ntau cov kev siv tshuaj thiab semiconductor ntawm 90 mus rau 95 degree, kev pom kev sib haum xeeb yog qhov tuab ntawm 1.5 txog 1.6 hli. Kev ua haujlwm kub nce me ntsis hauv qab 1.2 hli, tab sis cov chromium cia tsis txaus rau kev khiav mus ntev. Rau cov thicknesses siab tshaj 1.8 hli, lub thermal txim elevates lub sheath kub mus rau theem uas passive zaj duab xis dissolving tshwm sim, counteracting cov txiaj ntsig ntawm cov thickness nce. Ib txwm hais txog qhov siab tshaj plaws qhov kub thiab txias, qhov yuav tsum tau ua kom tiav (electropolished) thiab watt ceev txwv thaum qhia. Qhov no hloov pauv cov qauv phab ntsa yooj yim rau hauv cov ncauj lus kom ntxaws siab - cov lus qhia txog dej ntshiab huv sib xws ncaj qha ntsig txog qhov kev xaiv qhov ntev rau ob qho tib si dej zoo khaws cia thiab thermal efficiency.