Dab tsi yog qhov sib txawv ntawm 308 thiab 316 vuam pas nrig?

308 thiab 316 vuam pas nrig (feem ntau yog lo lus cim ER308 thiab ER316 nyob rau hauv ABS AWS ANTS A5.9 cov qauv siv thiab cov khoom siv ua kom haum rau cov ntawv thov txawv txawv. Nkag siab txog lawv qhov sib txawv yog qhov tseem ceeb rau kev ua kom muaj kev ncaj ncees Weld, corrosion tsis kam, thiab kev ua haujlwm ntev hauv ntau yam kev lag luam.
1. Tshuaj lom neeg sib xyaw: cov tub ntxhais sib txawv
Qhov sib txawv ntawm kev sib txawv ntawm 308 thiab 316 vuam pas nrig nyob hauv lawv cov ntsiab lus alloy, uas cuam tshuam ncaj qha rau lawv qhov kev ua tau zoo:
• EM3 {{{{{{}} 8: Raws li 304 stainless hlau (tsawg dua los yog sib npaug ntawm 0.08%) thiab manganese (tsawg dua los yog sib npaug rau 2%). Nws tsis muaj Molybdenum-ib lub ntsiab lus tseem ceeb rau kev txhim kho corrosion tsis kam nyob rau hauv ib puag ncig hnyav.
• ER316: Tau los ntawm 316 stainless hlau, nws khaws cov chromium zoo li cas (16-18%) thiab npib tsib} (1} )-3% molybdenum (mo). Qhov no molybdenum yog ib tug "corrosion fighter tsis kam rau pitting, corrosion, thiab tawm tsam los ntawm chloride-nplua nuj kua. Nws tseem muaj dua li silicon (tsawg dua los yog sib npaug rau 0.75%) rau kev txhim kho weld fluidity.
2. Ua Tau Ntau Yam Khoom Siv Hluav Taws Xob
Txhua tus pas nrig yog tsim kom phim cov chemistry ntawm tshwj xeeb stainless hlau lub hauv paus cov hlau, kom ntseeg tau weld hlau ua ib qho zoo sib xws rau niam txiv cov khoom:
• ER308: zoo tagnrho rau vuam 304 thiab 304L stainless hlau-feem ntau cov roj av tsis tshua muaj cua sov, siv rau hauv cov ntawv thov dav dav. Nws tseem ua haujlwm rau kev koom nrog 301, 302, lossis 305 alloys, raws li nws cov chromium-npib tshuav nyiaj los tiv thaiv carbide dej nag (ua rau muaj kev cuam tshuam corrosion).
• ER316: Tsim los rau Weld 316 thiab 316L stainless hlau, uas yog molybdenum-alloy rau ib puag ncig hnyav. Nws tseem haum rau 317 alloys (siab dua Molybdenum) thiab tuaj yeem siv los koom 304 mus rau 316 thaum corrosion tsis xav kom phim lub 316 lub hauv paus hlau.
3. Corrosion Kuj: Ib qho tseem ceeb sib faib
Lub xub ntiag ntawm Molybdenum hauv 316 cov pas nrig tsim lub stark sib piv hauv corrosion kev ua haujlwm:
• ER308: Muaj qhov zoo tsis kam mus rau cov kua qaub me me, cov khoom siv tshuaj yeeb hauv atmosphegerred, thiab dej yug txawv qhua. Txawm li cas los xij, nws yog qhov yooj yim rau pitting thiab crevice corrosion hauv chloride ib puag ncig (piv txwv li cov ntsev tsis zoo, lossis muaj cov tshuaj lom neeg xws li tshuaj dawb). Nws ua tau zoo nyob rau hauv qhuav, huv, lossis tsawg chloride chaw tab sis tawm tsam nyob rau hauv "ntub" lossis txhoj puab heev.
• ER316: Lub Molybdenum hauv ER316 ua cov txheej oxide tiv thaiv uas tiv taus chloride ions, ua rau nws ruaj khov nyob rau hauv ib puag ncig hnyav. Nws tiv thaiv dej hiav txwv, brines, sulfuric acid (dilute mev), thiab cov kuab tshuaj-nqis uas muaj 308 yuav croav sai. Piv txwv li, hauv 5% ntawm 5% NACL (Kev ntsuas dej qab ntsev) Imms tau qhia txog li 308 tsawg dua 308 Welds)
4. Cov Khoom Siv Neeg Kho Tshuab
Ob lub pas dej tau ua cov qauv siv vsds nrog kev ua kom zoo dua thiab tawv, tab sis 316 sawv hauv qee qhov xwm txheej:
• Lub zog tensile: er308 welds feem ntau muaj lub zog tensile ntawm 80, {}}}}}}}}}}}}
• Kev ua yeeb yam kub: ER316 khaws lub zog zoo dua ntawm cov ntawv thov kub siab (li ER308, ua rau kev siv cua sov zoo li kev tso pa hluav taws xob lossis cov chaw ua kom sov.
• Deventity: Ob txoj kev pab elongation elongation ntawm 35-45%, kom tau txais kev vam meej weld yooj yim thiab tiv taus tawg nyob rau hauv kev ntxhov siab.
5. Daim ntawv thov: qhov twg siv txhua tus pas nrig
Lawv cov khoom siv sib txawv tsav txoj kev siv divergent siv cov xwm txheej:
• ER308: vam meej rau cov hom phiaj dav dav, muaj ib puag ncig tsis muaj zog, xws li:
◦ Cov Khoom Noj Ua Noj Ua Khoom Noj (piv txwv li, Cov Hlau Hlau Stainless Hlau, Conveyors)
◦ Architectural nta (handrails, facades)
◦ Cov kav dej tau los yog cov cuab yeej siv hluav taws xob (tshuab ntxuav tais diav, tub yees)
• ER316: Kev ua rau muaj kev zoo siab lossis cov chaw hauv chloride, suav nrog:
◦ Marine kho vajtse (Nkoj Hulds, Offshore platform)
◦ Kev Tso Tsheb Hlau thiab Pipelines (Tuav Cov Roj Acids, ntsev)
◦ Khoom siv tshuaj kho mob (kom tsis muaj menyuam ua haujlwm, phais cov cuab yeej)
◦ Cov av qeeg ntawm (txuas hniav, dej hiav txwv Infake tshuab)
6. Vuam txiav txim siab
Thaum ob tus pas nrig tau sib xws nrog TIG (GTAW) thiab MIG (GMAW) cov txheej txheem, qhov sib txawv me me hauv kev taug kev nyob:
• Cov lus qhia tshav kub: ER316 yuav xav tau me ntsis cov cua sov dua li Er308 los xyuas kom meej tag nrho cov fusion, vim nws cov ntsiab lus me me (uas me ntsis nce melting point).
• Kev tiv thaiv roj: ob qho tib si ua tau zoo tshaj plaws nrog Cov Ntshiab Progon (99.99%) lossis cov khoom sib xyaw ua ke) kom tiv thaiv oxidation ntawm chromium.
• Tom qab kev kho vaj tsev weld: tsis tas yuav tsum muaj cov ntawv tso tawm Weld-Weld tau txais txiaj ntsig los ntawm kev them nyiaj rau kev txhawb nqa kom rov qab ua nws cov oxide txheej.
Xaus: Kos cov pas nrig txoj cai
Qhov kev xaiv ntawm 308 thiab 316 vuam rods hinges ntawm ib puag ncig weld yuav ntsib:
• Siv ER308 rau tus nqi-rhiab, cov ntawv thov tsis muaj ntshav nrog 304-} series} series} series base cov hlau.
• Siv ER316 thaum muaj tshuaj pleev tau, tshuaj tiv thaiv, lossis lub zog kub yog qhov tseem ceeb yog qhov tseem ceeb, tshwj xeeb yog kev sib tw ua ke.
Missmatching pas nrig (piv txwv li, siv 308 ntawm 316 hauv kev ua haujlwm weld) tuaj yeem ua rau weld ua ntej, siv 318 qhov twg) nce nqi yam tsis muaj nqi. Ib txwm dlhos tus muab tub lim hlau nrog cov hlau hauv cov hlau thiab daim ntawv thov ib puag ncig kev xav tau.