Dab tsi yog Tsawg-Alloy Seawater Corrosion-Resistant Steel?
Tsawg- alloy seawater corrosion- cov hlau resistant yog ib tsev neeg ntawm cov qauv hlau alloyed kom lub compact, tiv thaiv xeb txheej ntaub ntawv nyob rau hauv seawater thiab marine atmospheres es tsis txhob xoob, ntxeem tau xeb ua los ntawm cov pa carbon hlau. Tag nrho cov ntsiab lus alloying yog txhob txwm tshaj tawm tsawg, feem ntau zoo hauv qab 2%, uas ua rau tus nqi ze rau cov pa roj carbon steel thaum muab lub neej kev pab ntau zaus nyob rau hauv ib puag ncig marine. Qhov kev sib xyaw ua ke yog vim li cas cov qhab nia no tau siv rau cov chaw nres nkoj, cov qauv hauv ntug dej hiav txwv thiab cov ntug dej hiav txwv qhov chaw uas kev tshuaj xyuas thiab kev saib xyuas yog qhov nyuaj thiab kim.
Cov qib tsis yog stainless hlau thiab lawv tsis nres corroding. Lawv cia siab rau qhov qeeb, tus kheej - kho oxide txheej, thiab rau cov qauv mus tas li lawv tseem siv ua ke nrog cov txheej txheem thiab kev tiv thaiv cathodic.
Lub Alloying Elements ua haujlwm li cas
Kev tiv thaiv corrosion los ntawm kev sib cuam tshuam ntawm ntau qhov sib ntxiv thaum lub sij hawm txheej txheem corrosion es tsis yog los ntawm ib qho khoom.
| Element | Muaj nuj nqi |
|---|---|
| Tooj liab thiab phosphorus | Txhawb nqa lub compact, adherent xeb txheej enriched nrog tooj liab thiab phosphorus tebchaw uas seals lub pores ntawm zoo tib yam xeb. |
| Chromium | Cov yeeb yaj kiab tseem ceeb- txhawb nqa lub zog hauv cov qib niaj hnub no, ua kom qhov ntom ntom thiab ruaj khov ntawm cov txheej txheem tiv thaiv |
| Nickel | Enriches txheej xeb ntxiv thiab txhim kho kev ua tau zoo nyob rau hauv marine atmospheric raug |
| Molybdenum | Counters pitting nyob rau hauv chloride-nplua nuj tej yam kev mob thiab pab repassivate thaum ntxov pit site |
| Aluminium | Tsim cov yeeb yaj kiab oxide tuab uas ntxiv rau lub cev thaiv, tshwj xeeb hauv chromium-molybdenum-aluminium system |
Cov phosphorus-cov kabmob tooj liab-nickel system tsim nyob rau hauv Tebchaws Meskas xyoo 1951 yog thawj qhov kev lag luam seawater corrosion-resistant steel. Nws cov ntsiab lus phosphorus ntawm 0.08 mus rau 0.15% muab kev ua haujlwm zoo tshaj plaws hauv thaj chaw ua haujlwm tab sis ua rau vuam nyuaj, thiab cov phaj siab tshaj li 20 hli tuab feem ntau tsis welded. Nyiv txoj kev loj hlob nyob rau xyoo 1960 tau txo phosphorus mus rau 0.03% lossis tsawg dua thiab hloov mus rau chromium-raws li alloy system ntawm kwv yees li 1% chromium, hauv tooj liab-chromium-phosphorus, tooj liab-chromium{7}{1} thiab phosphorus tooj liab-chromium{19}}molybdenum variants, uas rov qab weldability thaum ua kom muaj zog corrosion. European chromium-aluminium system ua raws tib txoj cai, thiab Suav kev tshawb fawb uas pib nyob rau hauv nruab nrab-1960s coj mus rau chromium{24}}molybdenum-aluminium system, tam sim no standardized hauv GB/T 30070 rau seawater corrosion-resistant steel phaj, nrog rau qib 10 Cr.Ale
Marine Corrosion Zones
| Zone | Qhov chaw | Corrosion cwj pwm |
|---|---|---|
| Marine huab cua | Saum toj splash ncav cuag | Ntsev-laen cua, nruab nrab thiab kuj sib xws |
| Splash tsam | Tsuas yog saum lub waterline, wetted los ntawm nthwv dej | Qhov chaw nruj tshaj plaws, nrog ntub - caij tsheb kauj vab qhuav, cuam tshuam yoj thiab plentiful oxygen |
| Tidal cheeb tsam | Nruab nrab ntawm qhov siab thiab qis | Alternating immersion thiab raug, moderated los ntawm galvanic coupling nrog rau submerged seem |
| Tag nrho immersed cheeb tsam | Hauv qab ntug dej hiav txwv | Oxygen- txwv tsis pub muaj kev sib ntaus sib tua, nrog biofouling tsim cov hlwb hauv zos |
| Seabed av nkos zone | buried nyob rau hauv sediment | Cov pa oxygen tsawg thiab qis dav dav, tab sis sulfate- txo cov kab mob tuaj yeem ua rau muaj kev tawm tsam hauv zos |
Vim tias ib qib coj txawv ntawm cov cheeb tsam ntawd, kev tiv thaiv corrosion, txheej specification thiab cathodic tiv thaiv tsim yuav tsum tau teem ib cheeb tsam ntawm ib cheeb tsam es tsis siv uniformly. Qhov chaw txaws yuav luag ib txwm tau txais kev tiv thaiv corrosion hnyav tshaj plaws thiab cov txheej txheem zoo tshaj plaws.
Qib thiab Alloy Systems
| Qhov system | Alloying hauv paus | Sau ntawv |
|---|---|---|
| Tooj liab -phosphorus-nickel | Cu, P, Ni | Thawj qhov system; zoo heev splash cheeb tsam kev ua tau zoo tab sis txwv weldability ntawm cov ntu tuab |
| Chromium -raws li | Cr nrog Cu, P, Al lossis Mo | Tsawg phosphorus rau kev txhim kho weldability, nyob ib ncig ntawm 1% chromium ua lub ntsiab corrosion-cov khoom tiv taus |
| Chromium{0}}aluminium | Cr, Al | Aluminium ntxiv rau ntxiv xeb txheej stability |
| Chromium{0}}molybdenum-aluminium | Cr, Mo, Al | Txheem nyob rau hauv GB / T 30070 rau seawater corrosion-resistant phaj; tsim Suav system siv rau seawater piping, shipbuilding thiab coastal petrochemical khoom |
Thaum xaiv qib, peb yam tseem ceeb tswj kev xaiv: tus qauv tswj hwm, uas rau cov haujlwm hauv Suav teb yuav yog GB / T 30070 rau seawater corrosion{1}}cov phaj resistant lossis GB / T 712 rau nkoj thiab dej hiav txwv engineering steel qauv; lub zog tawm los xav tau los ntawm kev tsim qauv; thiab corrosivity ntawm qhov tseeb installation cheeb tsam. Daim ntawv pov thawj tshuaj ntsuam xyuas zeb yuav tsum tau kuaj xyuas tus qauv es tsis yog cia siab rau lub npe qib ib leeg.
Vuam thiab kev tiv thaiv yuav tsum tau
Qhov siab phosphorus cov ntsiab lus ntawm tus thawj tooj liab-phosphorus-nickel system yog txhob txwm ua lag luam- tawm ntawm kev ua haujlwm corrosion thiab weld cracking txaus ntshai, thiab nws yog vim li cas cov qib niaj hnub khaws phosphorus nyob rau theem qis. Qhov twg cov chemistry tso cai rau welding, xyaum ua raws li cov kev cai dav dav rau qis- alloy structural steel: qis-hydrogen consumables xws li E5015 hom, tswj preheat, thiab post-weld stress nyem qhov twg yuav tsum tau los ntawm lub thickness thiab cov kev cai specification. Cov txheej txheem vuam yuav tsum tsim nyog rau qib tiag tiag ua ntej kev tsim khoom, vim tias cov hlau txuas ntxiv hloov pauv cov lus teb ntawm tshav kub- thaj tsam cuam tshuam.
Cov hlau no tsis hloov cov txheej tiv thaiv los yog kev tiv thaiv cathodic hauv cov txheej txheem marine mus tas li; lawv txo qhov tshwm sim ntawm cov txheej txheej tawg thiab ua kom ntev lub sijhawm ntawm kev saib xyuas. Qhov twg cov txheej xeb tsis tuaj yeem zam tau txhua yam, xws li hauv cov raj xa hluav taws xob, lub twj tso kua mis sab hauv thiab lub rooj zaum valve, stainless hlau lossis clad phaj tseem yog qhov kev xaiv zoo dua. Kev taw qhia tsim kev tiv thaiv yog muab los ntawm cov ntaub ntawv xws li DNV-RP-B401 rau cathodic tiv thaiv tsim, EN 10225 rau weldable structural steels rau ruaj nyob rau hauv ntug dej hiav txwv qauv, thiab ISO 12944-9 rau kev tiv thaiv xim tshuab rau offshore lug, thaum qaub marine kev pab cuam yog hais los ntawm ISO 12944-9
Daim ntawv thov thiab kev txwv
Chaw nres nkoj cov qauv: wharves, jetties, breakwaters thiab daim ntawv piling
Offshore platform ob txhais ceg thiab txaws cheeb tsam cov tswv cuab
Coastal txuas hniav, piers thiab ntug hiav txwv fais fab nroj tsuag cua txias tshuab
Kev siv dej hiav txwv thiab cov kav dej tawm, thiab cov kav dej submarine txhawb nqa
Nkoj hull plating nyob rau hauv tidal thiab splash zones
Cov qib no txo tus nqi corrosion zoo heev piv nrog cov pa roj carbon steel, tsim kom ruaj khov thiab ib nrab ntawm tus kheej - kho xeb txheej, thiab zam cov txheej txheem vuam txheej txheem thaum cov ntsiab lus phosphorus tsawg. Txawm li cas los xij, lawv yuav tsis sib haum rau kev tiv thaiv corrosion ntawm stainless hlau, lawv yuav tsis tshem tawm pitting nyob rau hauv siab tsis khov siab -chloride los yog kab mob- tej yam kev mob, thiab lawv tsis ua hauj lwm sib npaug zos nyob rau hauv txhua cheeb tsam: lub splash cheeb tsam yog qhov chaw uas lawv ntxiv tus nqi tshaj plaws.
FAQ
Q: Dab tsi yog qhov qis- alloy seawater corrosion-resistant steel?
Cov qauv hlau nrog me me ntxiv ntawm tooj liab, phosphorus, chromium, npib tsib xee, molybdenum thiab txhuas uas tsim cov txheej txheem tiv thaiv xeb hauv dej hiav txwv, ntawm tus nqi ze ntawm cov hlau carbon.
Q: Nws kav ntev npaum li cas dua li carbon steel hauv dej hiav txwv?
Nyob rau hauv cov xwm txheej txhoj puab heev qhov corrosion feem ntau yog ob peb zaug qis dua li cov pa roj carbon steel, uas txhais tau hais tias ua haujlwm ntev dua. Tus nqi pes tsawg nyob ntawm qhov kub thiab txias, salinity, ntws thiab biofouling.
Q: Puas yog cov hlau no tseem xav tau txheej thiab tiv thaiv cathodic?
Yog lawm. Lub alloying qeeb corrosion tab sis tsis nres nws, yog li cov qauv mus tas li tseem xav tau cov txheej txheem tiv thaiv thiab cathodic tiv thaiv, nrog rau cov hlau txo qhov tshwm sim ntawm cov txheej txheem hauv zos.
Q: 10CrMoAl yog dab tsi?
10CrMoAl yog tsim los ntawm Suav chromium-molybdenum-aluminium seawater corrosion-resistant steel qib standardized hauv GB/T 30070, siv rau seawater piping, shipbuilding thiab coastal petrochemical khoom.
Q: Vim li cas phosphorus txwv nyob rau hauv cov qib niaj hnub?
Cov phosphorus siab txhim kho corrosion kuj tab sis ua rau muaj kev cuam tshuam rau kev sib tsoo thiab txwv tsis pub vuam ntawm cov ntu tuab, yog li cov qib niaj hnub ua kom qis qis thiab cia siab rau chromium hloov.
Q: Puas yog seawater corrosion-resistant steel hloov stainless hlau?
Tsis yog. Nws yog cov khoom siv uas ua tau zoo tshaj cov pa roj carbon steel hauv marine kev pabcuam, tab sis cov hlau tsis muaj steel thiab clad phaj tseem xav tau rau cov khoom siv hluav taws xob, cov twj tso kua mis thiab lwm yam dej num uas tsis tuaj yeem lees txais.
