Nqus thiab Outgassing Considerations rau -196℃Cartridge rhaub
Qhov chaw simulation chambers thiab siab - cov cuab yeej tshawb nrhiav lub tshuab nqus tsev nthuav qhia cov teeb meem tshwj xeeb uas mus deb dhau ntawm cov txheej txheem cua sov cryogenic. Hauv lub tshuab nqus tsev, cua sov tsis tuaj yeem txav los ntawm convection- txhua qhov cua sov yuav tsum yog hluav taws xob lossis hluav taws xob. Qhov kev hloov pauv tseem ceeb hauv kev hloov hluav taws xob hloov pauv hloov pauv hloov pauv li cas lub tshuab rhaub dej kub [cartridge rhaub] ua tau zoo, thiab cov teeb meem tsuas yog sib npaug thaum cov khoom siv kuj ua haujlwm ntawm cov kua nitrogen.
Qhov teeb meem outgassing catches ntau engineers tawm tus neeg zov. Thaum rhuab, cov ntaub ntawv siv los tsim cov txheej txheem cartridge tso cua sov tuaj yeem tso cov tshuaj tsis haum uas ua rau lub tshuab nqus tsev vacuum los yog tso cov khoom tso rau ntawm qhov chaw kho qhov muag. Nyob rau hauv qhov chaw simulation daim ntaub ntawv, hydrogen thiab carbon monoxide tuaj yeem los ntawm cov khoom siv ntau thiab cov kab mob ntawm qhov chaw, nyob ntawm qhov chaw kho qhov muag txias thiab ua rau lawv cov txiaj ntsig zoo. Qhov no tsis yog qhov kev txhawj xeeb ntawm kev xav- nws yog hom kev ua tsis tau zoo uas tau ua kom puas suav tsis txheeb cov phiaj xwm kev sim thiab ncua sij hawm tseem ceeb hauv cov phiaj xwm aerospace.
Kev xaiv cov khoom nyob rau hauv lub tshuab nqus tsev ib puag ncig ua raws cov kev cai sib txawv dua li cov ntawv thov hauv huab cua. Stainless hlau 304, zoo kawg nkaus tsim nyog rau kev lag luam cua sov, outgasses ntau dhau hauv lub tshuab nqus tsev tshwj tsis yog kho tshwj xeeb. Txawm tias muaj electropolishing thiab lub tshuab nqus tsev ci, 304 tseem tsis txaus rau qhov chaw simulation ua haujlwm. Lub microstructure ruaj khov ntawm 316L nrog cov ntsiab lus carbon tsawg ua tau zoo dua hauv lub tshuab nqus tsev, thiab thaum lub tshuab nqus tsev- raug rho tawm haujlwm kom tshem tawm cov volatiles, nws cov nqi hluav taws xob dhau los ua tau zoo rau ntau daim ntawv thov.
Rau kev siv kho qhov muag lossis ntsuas qhov tseem ceeb, Inconel 600 thiab 625 yog cov khoom xaiv. Cov npib tsib xee -chromium alloys tuav cov purity zoo heev thiab ruaj khov oxide nplai uas tso tawm roj tsawg heev. Qhov sib txawv ntawm qhov kev ua tau zoo tshaj plaws yog staggering- npaj kom zoo Inconel tuaj yeem ncav cuag 10⁻¹² Torr-liter / sec-cm², thaum npaj tsis zoo 304 tsuas yog ua tiav 10⁻⁸ lossis loj dua. Qhov ntawd yog 10,000-fold sib txawv uas txiav txim siab seb qhov chaw simulation ua haujlwm lossis ua tsis tiav.
Cov cwj pwm hluav taws xob hloov pauv loj heev hauv lub tshuab nqus tsev thiab. Terminals uas muaj rwb thaiv tsev txaus nyob rau hauv cov huab cua yuav arc thoob plaws hauv lub tshuab nqus tsev, tshwj xeeb tshaj yog nyob rau hauv siab kub qhov twg outgassing thiab cov ntaub ntawv hloov pauv tshwm sim. Cov tshuab nqus tsev tshwj xeeb lub tshuab nqus tsev tso cua sov [cartridge rhaub] siv cov kab txuas txuas ntxiv -ntev ntev ntawm qhov chaw insulating- los tiv thaiv kev tawg. Txheem sealing txoj kev kuj tsis ua hauj lwm hauv lub tshuab nqus tsev. Organic sealants zoo li silicone lossis epoxy tsis tuaj yeem siv vim tias lawv tawm. Hermetic sealing nrog iav- rau- cov qauv hlau lossis ceramic yuav tsum tau ua.
Qhov tsis muaj convective txias hauv lub tshuab nqus tsev txhais tau tias kev tswj xyuas thermal xav tau kev xav sib txawv. Thaum tshav kub kub tuaj yeem tsuas yog khiav tawm los ntawm kev sib txuas mus rau qhov chaw mounting lossis hluav taws xob mus rau qhov chaw nyob ib puag ncig. Qhov no ua rau thermal gradients nyob rau hauv lub tshuab cua sov hnyav dua, tshwj xeeb tshaj yog thaum pib pib ntawm -196 degree. Kub gradients ntawm ntau tshaj 800 degrees Celsius ib centimeter tuaj yeem tsim hla cov khoom sib cuam tshuam hauv thawj vib nas this ntawm kev ua haujlwm. Nyob rau hauv lub tshuab nqus tsev, tsis muaj huab cua mus rau nruab nrab cov gradients, lub thermal shock stresses intensify.
Surface finish plays lub luag haujlwm tseem ceeb hauv lub tshuab nqus tsev. Electropolishing tsim ib tug du, passive nto nrog tsawg heev daig kab mob. Cov tshuab polishing yoojyim ua haujlwm- cov txheej txheej tawv tawv nrog cov yam ntxwv tsis zoo. Tshuaj passivation stabilizes oxide txheej. Cov kev kho saum npoo no, ua ke nrog kev xaiv cov khoom siv hauv paus, txiav txim siab seb lub tshuab cua sov puas ua rau lub tshuab nqus tsev los yog tswj xyuas cov qauv kev huv huv.
Rau siab -cov chaw tshawb fawb lub tshuab nqus tsev, cov ntaub ntawv pov thawj uas qhia tus nqi outgassing yog cov ntaub ntawv tseem ceeb. Tshwj xeeb qis- kev tsim tawm cov khoom siv hluav taws xob siv siab- purity magnesium oxide, ua tib zoo xaiv cov ntaub ntawv foob, thiab lub tshuab nqus tsev ci tom qab kev tsim khoom kom txo qis cov pa phem. Qee daim ntawv thov xav tau lub tshuab cua sov nrog ua- hauv cov thermocouples rau kev tawm tswv yim ncaj qha kub, tab sis cov thermocouple hlws ris yuav tsum tau muab hluav taws xob cais tawm ntawm lub rhaub hluav taws xob kom tsis txhob muaj cov voj voog hauv av thiab ntsuas qhov yuam kev.
Cov hluav taws xob hluav taws xob thermal ntawm lub tshuab cua sov kuj tseem ceeb hauv lub tshuab nqus tsev. Deg emissivity tswj yuav ua li cas zoo hloov cua sov los ntawm hluav taws xob. Oxidised nto emit ntau cua sov, thaum polished hlau emit tsawg heev. Kev ua kom zoo ntawm lub tshuab cua sov sheath nto kho kom zoo rau cov hluav taws xob hluav taws xob lossis kev tawm hluav taws xob tsawg yuav tsum tau ua tib zoo ua lag luam- tawm kev txiav txim siab.
Thaum kawg, qhia txog lub tshuab rhaub dej kub [cartridge heater] rau kev sib xyaw ua ke cryogenic thiab lub tshuab nqus tsev xav tau txav deb tshaj li cov txheej txheem catalog muab. Kev sib xyaw ua ke ntawm huab cua txias, lub tshuab nqus tsev tawm qhov txwv, thiab hluav taws xob- hloov pauv cov cua sov ua rau cov kev xav tau uas tsuas yog kev tsim kho tshwj xeeb tuaj yeem ua tiav.
