Cov Khoom Siv Kev Tshawb Fawb ntawm Thermocouple Alloys: Vim Li Cas Qee Cov Hlau Ua Haujlwm

Hauv cov txheej txheem cua sov, qhov ntsuas kub tsis sib haum yog qhov mob taub hau tsis tu ncua- qhov sib txawv me me tuaj yeem ua rau cov khoom tsis raug, nkim zog, lossis txawm tias cov khoom puas tsuaj. Ntawm txhua qhov ntsuas kub- ntsuas cov cuab yeej, cov thermocouples sawv tawm rau kev ua haujlwm ntev thiab dav qhov kub, tab sis ntau tus neeg siv pom tias tsis yog txhua lub thermocouples ua tau sib npaug hauv cov xwm txheej hnyav. Qhov sib txawv tseem ceeb yog nyob rau hauv cov khub hlau siv hauv lawv cov kev tsim kho, cov ntsiab lus hauv paus hauv cov ntaub ntawv tshawb fawb uas cuam tshuam ncaj qha rau qhov raug thiab lub neej ntev.

Thermocouples ua haujlwm raws li cov nyhuv Seebeck: thaum ob lub hlau sib txawv tau koom nrog ntawm ob qhov sib txuas thiab raug rau qhov sib txawv ntawm qhov kub thiab txias, qhov ntsuas qhov ntsuas tau tsim, uas cuam tshuam rau qhov kub hloov pauv. Raws li kev paub dhau los, tsis yog txhua tus khub hlau tsis sib xws tuaj yeem ua haujlwm zoo rau kev siv tswv yim. Cov khub hlau zoo tshaj plaws yuav tsum ua kom tau raws li ob qho tseem ceeb: cov khoom siv hluav taws xob ruaj khov thiab muaj peev xwm ua tau raws li qhov chaw ua haujlwm.

Common coj mus muag thermocouple hlau khub yog ua tib zoo xaiv raws li cov qauv no. Piv txwv li, Hom K (Chromel-Alumel, npib tsib xee-chromium vs. npib tsib xee-aluminium) yog siv dav tshaj plaws vim nws ruaj khov zoo ntawm -270℃thiab 1260℃. Nws cov alloy muaj pes tsawg leeg tiv thaiv oxidation ntawm qhov kub thiab txias, ua rau nws tsim nyog rau feem ntau ntawm cov tshuab cua sov thiab cua sov. Hom J (Hlau-Constantan) ua tau zoo hauv kev txo cov huab cua tab sis txwv rau 750℃vim tias hlau oxidizes sai dhau qhov kub no. Hom S (Platinum-Rhodium vs. Platinum) ua tau zoo nyob rau hauv cov xwm txheej kub siab txog li 1600 degree, txawm hais tias nws cov nqi siab txwv tsis pub siv rau cov ntawv thov xws li chav ntsuas cua sov lossis cov khoom siv dav hlau.

Txawm li cas los, ntau tus neeg siv overlook ib puag ncig yam tseem ceeb thaum xaiv cov thermocouples, ua rau tsis ua hauj lwm ntxov ntxov. Piv txwv li, Hom K thermocouples degrade sai nyob rau hauv sulfur- ib puag ncig nplua nuj, raws li sulfur reacts nrog npib tsib xee los ua nkig tebchaw. Hauv cov xwm txheej zoo li no, Hom N thermocouple (Nicrosil-Nisil) nrog kev txhim kho sulfur yog ib qho kev xaiv zoo dua. Lwm qhov pitfall yog tsis quav ntsej xaim rwb thaiv tsev-siab- qhov kub thiab txias ib puag ncig yuav tsum tau ceramic lossis ntxhia- insulated cables, thaum cov organic insulators zoo li PVC yuav yaj thiab ua rau luv luv Circuit Court saum 100 degree.

Cov ntsiab lus ntawm kev teeb tsa kuj cuam tshuam rau kev ua tau zoo, txawm tias muaj cov khub hlau zoo. Kev sib txuas tsis zoo nrog qhov ntsuas qhov saum npoo tsim ntsuas kev lag luam, thaum cov hlau ntev ntev ua rau muaj teeb meem cuam tshuam. Raws li kev paub dhau los, cov thermocouple junctions yuav tsum tau txuas mus rau lub hom phiaj ntawm qhov chaw, thiab cov xov hlau txuas ntxiv yuav tsum phim cov hlau alloy ntawm lub thermocouple nws tus kheej - siv cov xov hlau tsis sib xws yuav qhia txog qhov yuam kev loj, ua rau cov ntaub ntawv kub tsis txaus ntseeg.

Cov ntaub ntawv tshawb fawb tom qab thermocouple alloys boils mus rau qhov ntsuas qhov ntsuas kub, kev tiv thaiv ib puag ncig, thiab tus nqi. Kev xaiv tus khub hlau zoo tsis yog hais txog kev xaiv qhov kev xaiv kim tshaj plaws, tab sis sib piv cov khoom siv hlau rau qhov kev khiav hauj lwm kub, cua, thiab qhov yuav tsum tau muaj tseeb. Kev xaiv kom raug thiab kev teeb tsa txuas ntxiv lub neej ntawm thermocouple, xyuas kom muaj kev tswj xyuas qhov kub thiab txias, thiab txo cov nqi ua haujlwm.

Cov xwm txheej muaj cua sov sib txawv-los ntawm me me- nplai batch furnaces mus rau lub tshuab cua sov loj txuas ntxiv-xav tau cov kev daws teeb meem thermocouple. Cov yam ntxwv xws li qhov kub thiab txias, ib puag ncig corrosiveness, thiab qhov chaw teeb tsa yuav tsum muaj kev ntsuam xyuas los txiav txim siab qhov zoo ntawm cov hlau, hom rwb thaiv tsev, thiab kev sib txuas tsim. Customized thermocouple configurations, txhawb nqa los ntawm cov khoom siv science txawj ntse, ua kom ntseeg tau qhov ntsuas kub uas ua raws li cov kev xav tau ntau lawm thiab cov qauv zoo.