Dab tsi yog qhov siab tshaj plaws 316 Stainless Hlau Sheath Phab Ntsa Thickness rau lub rhaub hluav taws xob hauv qhov siab -Purity Deionized Dej siab tshaj 90 Degrees Celsius? Qhov siab tshaj plaws 316 Stainless Steel Sheath Phab Ntsa Thickness yog dab tsi rau lub rhaub hluav taws xob hauv qhov kub siab -Purity 90 Degrees Degrees Degrees?
Tso lus
High-purity deionised water is a dilemma for engineers designing electric immersion heaters for semiconductor manufacturing, medicinal water systems and laboratory equipment. Deionised water is highly corrosive to many metals since it lacks dissolved ions to provide protective passive layers, even though it has great electrical resistance. The passive chromium oxide coating on 316 stainless steel is stable in deionised water at room temperature. However, at higher temperatures (>80 degree) solubility ntawm oxygen tee thiab lub peev xwm corrosion tsub kom qhov kev hloov ntawm passive mus rau active corrosion. Lub 316 sheath phab ntsa thickness tswj cov kev tiv thaiv corrosion tshaj lub neej kev pab cuam ntawm lub rhaub thiab qhov kub ntawm qhov chaw rau ib tug tej yam watt ceev. Tshaj tawm corrosion tus nqi txheeb cais, nrog rau cov kev paub dhau los ntawm kev lag luam dej ultrapure, yog siv los txiav txim siab qhov siab tshaj plaws ntawm phab ntsa thickness rau 316 sheaths hauv siab purity deionised dej kev pab cuam.
Mechanisms ntawm Corrosion ntawm 316 Stainless Hlau nyob rau hauv High Temperature Deionised Dej
Hauv cov dej purity deionised siab (resistivity> 1 megohm-centimeter), cov concentration ntawm cov ions tsis zoo, xws li chlorides, tsawg heev. Tab sis qhov tsis muaj cov ntsev yaj tsis tas yuav ua rau dej tus phooj ywg. Rau qhov kub thiab txias tshaj 80 degree, 316 stainless hlau yog feem ntau ua rau corrosion thiab hnyav dua rau hauv cheeb tsam corrosion ntawm qhov chaw uas cov zaj duab xis passive tawg. Tus nqi corrosion nyob rau hauv cov dej deionised yog Arrhenius muaj feem xyuam, nce los ntawm ib qho ntawm ob rau txhua 25℃qhov kub thiab txias. Tus nqi corrosion ntawm 316 hauv dej deionised ntawm 90℃yog kwv yees li 0.02 txog 0.05 hli / xyoo. Tus nqi nce mus rau 0.10-0.20 millimeters ib xyoos ntawm 120 ° C. Ntawm 150℃tus nqi yog 0.30-0.50 mm / xyoo. Txawm hais tias cov nqi no yuav zoo li qis, rau lub rhaub dej kub uas tsim los ua haujlwm tsis tu ncua rau 5 mus rau 10 xyoo, qhov hnav ntawm 0.10 hli ib xyoo nruab nrab yog 0.5 txog 1.0 hli ntawm phab ntsa tuab. Thawj txheej txheej thickness ntawm 1.0 hli yuav txo mus rau 0.5 hli tom qab tsib xyoos, thaum txhua yam kev ncaj ncees yog dubious. Lub rusting yog tsis zoo txawm. Pitting thiab crevice corrosion, tshwj xeeb tshaj yog nyob rau hauv mounting interfaces thiab weld aav, tuaj yeem ua rau qhov nkag mus rau hauv cheeb tsam ntawm ob mus rau tsib npaug ntau dua li qhov dav dav corrosion.
Cov teebmeem ntawm Phab Ntsa Thickness thiab Kev Pabcuam Lub Neej ntawm Deionised Dej
Kev sib raug zoo ntawm 316 sheath phab ntsa thickness thiab kev pab cuam lub neej nyob rau hauv high kub deionised dej yog ze li ntawm linear yog hais tias nws yog feem ntau corrosion yog lub ntsiab mechanism. Rau 5 xyoo lub neej ntawm 95℃nrog corrosion tus nqi ntawm 0.04 hli / xyoo qhov yuav tsum tau muaj corrosion yog 0.20 hli. Qhov no nrog qhov tsawg kawg nkaus ntawm phab ntsa thickness ntawm 0.7 hli txhais tau hais tias yuav tsum tau pib phab ntsa thickness ntawm 0.9 hli. Ib daim ntaub ntawm 1.2 hli yuav muab qhov kev nyab xeeb ntawm 0.3 hli dhau thiab siab dua qhov kev txwv corrosion, thiab yuav muab lub neej ua tau ntev tshaj li yim xyoo. Tab sis rau qhov muab watt ntom ntom, cov phab ntsa tuab txhais tau tias kub dua rau ntawm sab nrauv. Kev kub siab saum npoo exponentially accelerate corrosion hauv dej deionised. Ib lub 2.0 hli sheath ntawm 10 W / cm² hauv 95℃dej yuav muaj qhov kub thiab txias ntawm 115 degree. Tus nqi corrosion ntawm qhov kub ntawm no yog nyob ib ncig ntawm 0.08 hli ib xyoo -ob npaug ntawm 1.2 hli sheath ntawm 105℃qhov kub thiab txias. Lub thicker sheath xav tau ntau dua corrosion, tab sis kuj corrodes sai dua. Qhov kev sib cuam tshuam no tsim cov phab ntsa zoo tagnrho rau lub neej kev pabcuam zoo tshaj plaws tsis yog kev sib raug zoo monotonic. Cov ntaub ntawv luam tawm corrosion tau siv los xam qhov zoo tshaj plaws 316 sheath phab ntsa thickness rau siab tshaj plaws kev pab cuam lub neej ntawm 95℃deionised dej ntawm 10 W / cm², uas yog nyob rau hauv qhov kev txiav txim ntawm 1.4 hli. Kev tiv thaiv corrosion tsawg dua 1.0 hli tsis txaus. Thaum ntau tshaj 1.8 hli qhov kev txhim kho corrosion ntau dua vim qhov kub thiab txias dua dominates cov khoom ntxiv.
Kev pom zoo siab tshaj phab ntsa Thickness rau kev pab cuam nrog Deionised Dej
Cov lus hauv qab no muab cov lus qhia siab tshaj plaws 316 sheath phab ntsa thicknesses rau hluav taws xob tso cua sov hauv siab -purity deionised dej kev pabcuam. Cov txiaj ntsig yog rau kev ua haujlwm tas mus li, qib oxygen <100 qhov chaw hauv ib billion, thiab kev tiv thaiv> 1 megohm-centimeter. Corrosion tus nqi yuav siab dua thiab yog li cov tshuab uas muaj cov pa oxygen ntau dua lossis qis dua purity thiab cov phab ntsa nyias yuav tsum tau muab.
Deionised Water Temperature Pom Zoo Watt Density Range Maximum Recommended 316 Sheath Phab Ntsa Thickness Expected Service Life at Maximum Thickness Failure Mode at Maximum Thickness Alternative Recommendation 80 – 90℃8 – 12 W/cm2 1.8 mm{5}} mm { 8 - 10 8 xyoo kev siv lub neej ntev - 8 xyoo corrosion 90℃12 - 15 W / cm 2 1.4 mm 6 - 8 xyoo Corrosion ntxiv rau thermal stress Standard kev pom zoo 90 - 100℃6 - 10 W / cm2 1.6 mm 5 - 7 xyoo Pitting ntawm qhov chaw defects Txo watt ntom rau lub neej ntev
90 - 100℃10 - 12 W / cm² 1.2 mm 4 - 6 xyoo General corrosion Feem ntau cov lus qhia 100 - 120℃4 - 8 W / cm² 1.2 mm 3 - 5 xyoos Accelerated corrosion Xav txog titanium sheath
100 - 120℃8 - 10 W / cm² 1.0 mm 2 - 3 xyoos Corrosion qaug zog Txhim kho alloy pom zoo
>120 degree<5 W/cm² Not advisable Unpredictable Sudden localised corrosion Use titanium or alloy C-276
Rau kev siv dej deionised tshaj 100 degree, engineers yuav tsum xav txog kev kho dua tshiab los ntawm 316 stainless hlau mus rau titanium los yog siab -nickel alloy xws li Alloy 22. Titanium muaj qhov corrosion ntawm qhov kub siab de- ionized dej ob qhov kev txiav txim siab qis dua 316. Qhov no tso cai rau cov phab ntsa ua haujlwm ntev dua. Tus nqi pib siab dua ntawm titanium feem ntau tau them los ntawm kev hloov pauv tsis tu ncua thiab tsis muaj kev phom sij ntawm cov hlau tsis huv hauv kev ua haujlwm rhiab heev.
Tsim cov kev hloov pauv kom nce kev pab cuam lub neej yam tsis tau nce cov yeeb nkab phab ntsa tuab
Thaum lub thickness 316 sheath yuav tsum tau rau txhua yam yog vim li cas xws li siab confinement los yog kev co kuj nyob rau hauv ib tug deionised dej daim ntawv thov, muaj peb tsim kho uas yuav offset lub ceev ceev corrosion los ntawm kub saum npoo. Thawj thiab zoo tshaj plaws yog kom txo cov watt ceev. Qhov txo qis ntawm qhov kub ntawm lub plhaub sab nraud los ntawm kwv yees li 10-15℃ntawm qhov txo qis ntawm watt ntom ntawm 12 W / cm² mus rau 6 W / cm² ua rau txo qis ntawm corrosion ntawm 30-40%. Kev lag luam tawm yog tias koj yuav xav tau ntev dua lossis loj dua cov cua sov kom tau txais tib lub zog tag nrho. Qhov thib ob alteration yog passivate lub sheath nto tom qab nws fabrication. Nitric acid los yog citric acid passivation kev kho mob tshem tawm cov hlau dawb thiab nto impurities los tsim kom muaj cov txheej txheem ntau dua thiab ruaj khov uas tiv thaiv corrosion pib. Hauv kev tshuaj ntsuam xyuas, passivated 316 sheaths tau nthuav tawm tus nqi corrosion uas yog 20-30% qis dua cov qauv tsis-passivated hauv dej deionised. Qhov thib peb kev hloov pauv yog dej chemistry tswj. Khaws cov pa oxygen hauv qab 5 feem ntawm ib billion. Siv cov pam vov nitrogen los yog lub tshuab nqus tsev degassing kom ua tiav qhov no. Qhov no txo cov tshuaj tiv thaiv cathodic thiab inhibits corrosion. Tab sis cov pa oxygen tsawg heev tuaj yeem ua rau cov yeeb yaj kiab tsis ruaj khov. Yog li lub qhov rais txwv ntawm 5-50 feem ntawm ib billion yog qhov zoo tshaj plaws. Cov kev hloov kho no tsis tuaj yeem ua tau rau feem ntau cov dej deionised thiab kev tswj ntawm phab ntsa thickness yog qhov tseem ceeb ntawm kev tswj lub neej corrosion. Hloov chaw ntawm kev xaiv phab ntsa tuab raws li cov cai ntawm tus ntiv tes xoo, cov kws tsim khoom yuav tsum qhia lub chaw tsim khoom siv lub tshuab cua sov ntawm lub neej kev pab cuam thiab thov kom suav cov nyiaj tiv thaiv corrosion raws li qhov xav tau ntawm kev ua haujlwm kub thiab watt ceev.
