Thermocouple degradation thiab kev pab lub neej

Kev pabcuam lub neej ntawm thermocouples yog cuam tshuam nrog lawv qhov kev puas tsuaj, uas yog hais txog qhov tshwm sim ntawm kev laus thiab kev puas tsuaj ntawm thermocouples tom qab siv. Thermocouples ua los ntawm cov hlau los yog alloys muaj cov nplej sab hauv uas maj mam loj hlob ntawm qhov kub thiab txias. Nyob rau tib lub sijhawm, cov hlau muaj me me ntawm impurities, thiab nws txoj hauj lwm lossis cov duab yuav hloov, thiab nws yuav hnov ​​​​mob nrog txo lossis oxidizing gases nyob ib puag ncig. Nrog rau cov kev hloov pauv saum toj no, lub thermoelectric electromotive quab yuam ntawm lub thermocouple kuj tseem yuav ua rau muaj kev hloov pauv. Yog li ntawd, qhov degradation ntawm thermocouples yog inevitable.
Kev pab lub neej ntawm thermocouples
Qhov degradation ntawm thermocouples yog ib qho txheej txheem uas nyuaj rau kev txheeb xyuas thiab yuav txawv nrog hom, txoj kab uas hla, kev khiav hauj lwm kub, cua, thiab lub sij hawm ntawm lub thermocouple. Lub neej kev pab cuam ntawm lub thermocouple yog hais txog lub sij hawm thaum lub sij hawm deterioration ntawm lub thermocouple ntau tshaj qhov tso cai yuam kev, thiab txawm tias thaum cov hlau tawg thiab siv tsis tau.
(1) Lub neej ntev ntawm cov thermocouples sib dhos
Lub stability ntawm thermocouples tsuas yog yuav tsum tau nyob rau hauv Suav cov qauv. Qhov kev hloov pauv ntawm cov hluav taws xob hluav taws xob hluav taws xob ua ntej thiab tom qab siv tau teev tseg ntawm qhov ntsuas kub rau 200 teev. Txawm li cas los xij, tsis muaj kev cai lij choj tau pom txog kev ua haujlwm lub neej. Cov kev xav tau rau lub neej kev pabcuam ntawm cov thermocouples hauv Nyij Pooj yog raws li lub sijhawm siv tas li ntawm cov thermocouples tau teev tseg hauv Japanese JIS (C-1602-1995) tus qauv. Rau B, R, thiab S hom thermocouples, nws yog 2000h, thaum rau K, E, J, thiab T hom thermocouples, nws yog 10000h.
Hauv kev siv tswv yim, cov thermocouples sib dhos feem ntau muaj cov raj tiv thaiv thiab tsuas yog siv nrog cov xov hlau liab qab hauv qhov xwm txheej tshwj xeeb. Yog li ntawd, nyob rau hauv feem ntau, lub lifespan ntawm lub raj tiv thaiv txiav txim lub lifespan ntawm lub thermocouple. Kev ntsuam xyuas ntawm lub neej kev pab cuam ntawm cov thermocouples yuav tsum tau ua raws li kev sau mus ntev thiab khaws cov ntaub ntawv raws li kev siv tiag tiag txhawm rau muab cov txiaj ntsig tau tseeb dua [5].
(2) Lub neej ntev ntawm armored thermocouples
Vim lub rwb thaiv tsev ntawm armored thermocouples los ntawm ib puag ncig sab nraud los ntawm kev tiv thaiv lub tes tsho, cov khoom siv tes tsho muaj kev cuam tshuam rau lub neej ntawm armored thermocouples.
Lub suab nrov nrov, thiab cov thermocouple xov hlau thiab lub tes tsho hlau yuav tsum raug xaiv raws li lub hom phiaj. Thaum cov khoom raug xaiv, nws lifespan nce nrog qhov nce ntawm txoj kab uas hla ntawm armored thermocouple. Piv nrog cov thermocouples sib sau ua ke, armored thermocouples muaj ntau qhov zoo, tab sis lawv lub neej kev pab cuam feem ntau qis dua li ntawm cov thermocouples sib dhos.
5. Cov lus xaus
Thermocouples yog cov khoom siv kub tshaj plaws hauv kev tshawb fawb thiab kev tsim khoom. Txawm hais tias lawv cov qauv yog qhov yooj yim, kev siv tsis tu ncua tseem tuaj yeem ua rau muaj kev ntsuas tsis raug. Tus sau piav qhia txog cov laj thawj tseem ceeb ntawm kev ua yuam kev hauv kev xaiv qhov ntsuas qhov ntsuas kub, qhov tob tob, lub sijhawm teb, thermal tawg, thiab thermal impedance ntawm thermocouples teb rau cov teeb meem tshwm sim thaum siv. Tus kws sau ntawv kuj tseem qhia txog kev ceev faj txog kev siv cov thermocouples, xws li heterogeneity, huab cua, rwb thaiv tsev tsis kam, xaiv oxidation ntawm K-hom thermocouples, K-state, thiab shunt yuam kev hauv armored thermocouples. Nws muaj txiaj ntsig zoo rau kev txhim kho kev ntsuas qhov tseeb thiab txuas ntxiv lub neej kev pabcuam ntawm thermocouples.