Sheath Materials rau Cartridge rhaub hauv Cryogenic Service
Stainless hlau sheath uas ua tau zoo kawg nkaus ntawm 200℃yuav tawg ntawm -100 degree. Cov khoom siv hluav taws xob ntawm cov hlau hloov pauv loj heev ntawm qhov kub thiab txias, thiab kev xaiv cov khoom siv rau cov khoom siv hluav taws xob hauv lub tshuab hluav taws xob yuav tsum nkag siab cov kev hloov no.
Lub sheath tiv thaiv cov hlau sab hauv thiab magnesium oxide rwb thaiv tsev thaum ua cua sov rau lub hom phiaj nruab nrab. Nyob rau ntawm qhov kub thiab txias, lub sheath yuav tsum tswj kom muaj kev ncaj ncees, tiv thaiv embrittlement, thiab ua kom haum rau thermal expansion qhov sib txawv ntawm cov khoom. Standard 304 stainless hlau, thaum tsim nyog rau ntau daim ntawv thov kev lag luam, ua kom qis qis qis dua -20 degree. Kev raug rau cov kua nitrogen kub thawb cov khoom no dhau ntawm nws qhov kev ua haujlwm txhim khu kev qha.
Stainless hlau 316 muaj kev txhim kho kev ua haujlwm rau kev pabcuam cryogenic. Qhov sib ntxiv ntawm molybdenum txhim khu kev tiv thaiv corrosion thiab pab tswj cov khoom siv dag zog ntawm qhov kub thiab txias. Cov hlau no tsis ua nkig zoo li lwm cov hlau tsis muaj hlau thaum txias. Rau cov ntawv thov mus rau kwv yees li -80 degree, 316 stainless hlau sheaths muab kev daws teeb meem zoo.
Rau cov ntawv thov uas xav tau tshaj plaws- cov uas muaj cov kua nitrogen ntawm -196℃lossis nquag thermal cycling ntawm cryogenic thiab siab kub -Inconel 600 lossis 800 series alloys sawv cev rau qhov kev xaiv zoo tshaj. Cov nickel-chromium alloys tuav txhua yam kev ncaj ncees thoob plaws qhov kub thiab txias ntawm -196℃rau +500℃. Lawv tuav thermal cycling thiab hnyav tej yam kev mob zoo dua li cov qauv stainless hlau, txawm tias tus nqi siab dua.
Inconel 625, npib tsib xee-chromium- molybdenum superalloy, ua kom pom cov yam ntxwv tshwj xeeb rau cov cua sov cua sov. Lub alloy tuav lub zog siab thiab toughness los ntawm cryogenic kub txog 980 degree, nrog qaug zog lub zog uas tseem zoo heev txawm nyob rau hauv cov kua nitrogen kub. Rau cov ntawv thov uas muaj kev rov ua dua thermal cycling ntawm huab cua txias thiab kub kub, cov khoom siv no muab kev ua haujlwm zoo tshaj plaws.
Thermal expansion txuam ntawm cov sheath thiab cov khoom siv sab hauv nthuav qhia lwm qhov tseem ceeb. Thaum lub tshuab cua sov lub tshuab cua txias txias los ntawm chav tsev kub mus rau -100 degree, lub hnab ntawv cog lus ntawm tus nqi sib txawv ntawm cov hlau tsis kam thiab magnesium oxide rwb thaiv tsev. Qhov sib txawv ntawm qhov sib txawv no ua rau muaj kev ntxhov siab uas tuaj yeem ua rau tsis ua haujlwm yog tias cov ntaub ntawv tsis sib haum. Tshwj xeeb npib tsib xee-hlau alloys ua tau zoo dua piv nrog cov qauv stainless hlau thaum caij tsheb kauj vab ntawm cryogenic thiab siab kub.
Kev xaiv ntawm cov khoom siv sheath kuj cuam tshuam rau kev ua haujlwm ntawm cov cua sov. Thermal conductivity sib txawv ntawm cov alloys ntawm qhov kub thiab txias. Cov ntaub ntawv nrog cov thermal conductivity ntau dua hloov cov cua sov ntau dua los ntawm cov hlau tsis kam mus rau lub hom phiaj nruab nrab. Qhov kev ua tau zoo no cuam tshuam rau watt ntom uas xav tau kom ua tiav qhov xav tau kub.
Kev tiv thaiv corrosion ntawm qhov kub thiab txias yuav tsum tau ua tib zoo saib xyuas cov tshuaj lom neeg ib puag ncig. Oxygen ntsiab lus, ya raws raug, thiab chloride muaj feem cuam tshuam cov sheath degradation. Inconel 625 los yog titanium muab kev tiv thaiv rau ntau tus neeg ua haujlwm corrosive ntsib hauv kev ua haujlwm cryogenic. Rau oxidizing tej yam kev mob ntawm qhov kub siab, aluminium coatings los yog Inconel 600 nrog siab chromium cov ntsiab lus daim ntawv tiv thaiv scale.
Cov txheej txheem tsim khoom cuam tshuam rau kev ua haujlwm sheath ntau npaum li cov khoom siv nws tus kheej. Seamless tubing muab cov phab ntsa tuab zoo sib xws ntau dua li cov welded tubing, kom ntseeg tau tias muaj cua sov hloov pauv. Kev kho deg xws li passivation tshem tawm cov kab mob hlau thiab rov ua cov txheej txheem chromium oxide tiv thaiv. Electropolishing tsim ib tug du, tsis yog - ntxeem tau nto uas tiv thaiv tshuaj tua kab mob.
Xaiv cov ntaub ntawv sheath zoo rau cov tshuab cua sov cryogenic yuav tsum ntsuas qhov kev ua tau zoo ntawm cov nqi txwv. Rau cov ntawv thov uas muaj qhov txias txias thiab txwv kev caij tsheb kauj vab, 316 stainless hlau feem ntau muab kev pabcuam txaus. Rau cov kua nitrogen txias, nquag caij tsheb kauj vab, lossis qhov chaw corrosive, Inconel alloys pom zoo rau lawv cov nqi siab dua los ntawm kev siv lub neej ntev thiab txo qis kev pheej hmoo.
