Thermocouple Antioxidant Properties Revealed: Cov khoom xaiv txiav txim siab txog kev ntsuas kub ntawm lub neej

Nyob rau hauv siab - qhov kub thiab txias kev lag luam, qhov oxidation tsis kam ntawm thermocouples ncaj qha cuam tshuam cov cuab yeej lifespan thiab ntsuas qhov tseeb. Cov ntaub ntawv sib txawv muaj cov yam ntxwv sib txawv ntawm qhov ua tau zoo hauv oxidizing ib puag ncig, thiab kev xaiv tsis raug tuaj yeem ua rau muaj kev hloov pauv ntau zaus lossis txawm tias muaj xwm txheej ntau lawm. Kab lus no muab ib qho kev soj ntsuam hauv - qhov tob ntawm oxidation tsis kam ntawm cov khoom siv thermocouple thiab tsom rau kev txiav- ntug kev tiv thaiv technologies hauv kev lag luam.

I. Precious Hlau Thermocouples: Qhov kawg tiv thaiv tiv thaiv siab -Tub kub Oxidation

Platinum-Rhodium Series (Hom S, Hom R, Hom B) Leveraging lub ntuj corrosion kuj ntawm precious hlau, lawv tau dhau los ua "tus qauv kub" rau ultra- siab- daim ntaub ntawv kub:

Hom S (Platinum-Rhodium 10-Platinum): Kev ruaj ntseg zoo heev hauv oxidizing thiab inert cua, nrog rau 1400℃rau ncua sij hawm. Txawm li cas los xij, lub platinum electrode yog nquag "silicon contamination" thaum raug silicon vapor lossis hlau vapor, ua rau tsis ua haujlwm.

Hom B (Platinum-Rhodium 30-Platinum-Rhodium 6): Ob chav platinum-rhodium qauv zam tsis muaj qhov cuam tshuam ntawm kev tsiv teb tsaws, nrog rau qhov kub siab tshaj plaws ntawm 1800℃. Lifespan nyob rau hauv oxidizing ib puag ncig yog 60% ntev dua li hom S, tab sis rhiab heev ntawm qhov kub thiab txias thiab tus nqi yog siab.

Tsis muaj zog txaus ntshai: Kev ua haujlwm tsis zoo nyob rau hauv kev txo cov huab cua (muaj H₂ thiab CO); sulfides tuaj yeem tsim tsawg- melting- taw tes eutectics nrog platinum, ua rau hlau tawg.

II. Base Hlau Thermocouples: Ib Txoj Kev Tiered rau Oxidation Resistance

Lub hauv paus hlau thermocouples tswj hwm kev lag luam kev lag luam, tab sis lawv cov oxidation tsis kam nthuav tawm peb -tiered kev ua tau zoo:

N-hom (NiCrSi-NiSilicon): Lub Hnub Qub nce siab hauv siab-Tub kub oxidation Resistance

Los ntawm kev ntxiv 14.4% chromium thiab 1.4% silicon los tsim cov Cr₂O₃ oxide zaj duab xis, nws cov oxidation tsis kam ntawm 1300℃yog 3 npaug siab dua li ntawm K- hom;

Nws tag nrho daws qhov teeb meem "ntsuab corrosion" (muaj peev xwm drift los ntawm grain ciam oxidation) ntawm 400 ~ 900 degree, ncua nws lifespan ntau tshaj 2 xyoo.

Hom K (NiChromium-NiSilicon): Ob chav - Ntug ntaj ntawm tus nqi- Ua tau zoo

Nrog tsuas yog 10% chromium cov ntsiab lus, oxide zaj duab xis yog feem ntau tawg saum 1000 degree, thiab leej faj nkag mus rau "sulfur embrittlement" thiab hlau tawg.

Kev xaiv oxidation tshwm sim nyob rau hauv 400 ~ 900℃ntau yam (chromium poob hauv qhov zoo electrode thiab silicon nce hauv qhov tsis zoo electrode), nrog rau txhua xyoo drift mus txog ± 8 degree.

Hom E (NiChromium-Constantan) & Hom J (Fe-Constantan): Dedicated rau nruab nrab thiab qis kub daim ntawv thov

Hom E tsis zoo electrode tooj liab-nickel alloy oxidizes sai dua 800 degree, thiab tsuas yog haum rau ib puag ncig tsawg dua lossis sib npaug li 800 degree.

Hom J hlau electrode oxidation tus nqi nce siab tshaj 500 degree, yuav tsum muaj kev sib cais ntawm cov pa oxygen.

III. Technological Breakthroughs: Los ntawm Kev Hloov Kho Khoom Siv mus rau Kev Tsim Kho Tshiab

Txhawm rau kov yeej cov kev txwv ntawm cov khoom siv, kev lag luam tau tsim cov cuab yeej tiv thaiv triple:

Microalloying Reinforcement: Ntxiv yttrium (Y) thiab rhenium (Re) rau N-hom thermocouples inhibits grain coarsening, ncua lifespan los ntawm 60% ntawm 900 degree;

Composite Protection Tube: Ua haujlwm "sandwich" qauv- txheej txheej ntawm silicon carbide ceramic (tiv taus sulfide / zinc vapor corrosion), nruab nrab txheej ntawm Al₆₀O₆₁ rwb thaiv tsev, thiab txheej txheej sab hauv siab -purity magnesium oxide rwb thaiv tsev-txog li 5 xyoos ntawm kev ua haujlwm ntawm cov cement 1200 degree;

Dynamic Compensation Algorithm: Kev sib koom ua ke ntawm cov qauv kev hloov kho kom tau txais kev them nyiaj rau 0.3% ~ 0.8% oxidation decay deviation hauv thermocouples siv ntau tshaj 3 xyoos.

IV. Phau Ntawv Qhia Kev Xaiv Tswv Yim: Kev Sib Tw Ntiag Tug Raws li Kev Ua Haujlwm

Oxidizing Atmospheres Tsawg dua lossis sib npaug li 1300 degree: Hom N yog nyiam, nrog kev tiv thaiv zoo dua los ntawm yttrium / rhenium microalloying.

Sulfur/Carbon Atmospheres: Tungsten-rhenium thermocouples yog siv, ua ke nrog silicon carbide tiv thaiv raj los thaiv cov xov xwm corrosive.

Nqus / Txo Cov Cuab Yeej: Hom J + 316L stainless hlau sheath ua ke los tiv thaiv H₂ / CO corrosion.

Cov xwm txheej uas muaj qhov kub thiab txias hloov pauv: Hom K armored nyias-walled tsim (phab ntsa thickness Tsawg dua lossis sib npaug li 0.5mm) txhim kho cov lus teb ceev.

Key Warnings: Type K should be used with caution in sulfur-containing environments >1000 degree; Hom S yuav tsum nyob deb ntawm cov vapors hlau!