1. Dab tsi yog qhov sib txawv tseem ceeb ntawm Incoloy 800H (UNS N08810) thiab Incoloy 800HT (UNS N08811), thiab vim li cas qhov kawg tshwj xeeb tau teev tseg rau qhov tseem ceeb siab -kub petrochemical rau cov khoom siv hluav taws xob?
Txawm hais tias ob qho tib si alloys koom rau tib tsev neeg (Fe-32Ni-21Cr nrog ntxiv ntawm Al thiab Ti), qhov sib txawv yog nyob rau hauv qhov tseeb chemistry tswj thiab ua rau cov khoom kub-kub txhua yam. Incoloy 800HT (UNS N08811) sawv cev rau kev tswj hwm nruj tshaj plaws thiab ua kom zoo tshaj plaws rau kev pabcuam huab.
Chemical Differences & Tswj:
Cov pa roj carbon: Ob leeg yuav tsum muaj qhov tsawg kawg nkaus ntawm 0.05-0.10%, tab sis 800HT muaj qhov nruj tshaj qhov txwv (0.10% max) thiab yuav tsum muaj qhov sib piv ntawm (Ti + Al) / C Ntau dua lossis sib npaug rau 12. Qhov kev nruj stoichiometry no ua kom txhua cov pa roj carbon stabilized zoo li TiC los yog (Timentates, Al) precipitate formation ntawm precipitates. nplej ciam teb.
Aluminium + Titanium: Cov ntsiab lus sib xyaw (Al + Ti) siab dua hauv 800HT (0.85-1.20% vs . 0.75-1.50% rau 800H), tshwj xeeb tsim los ua kom tau raws li 12: 1 piv nrog cov pa roj carbon rau kev pom kev nkag siab zoo.
Grain Size: Ib qho ASTM A424, 800HT yuav tsum muaj cov tshuaj anneal ntawm qhov tsawg kawg nkaus ntawm 2100℃F (1149 degree), uas ua rau muaj kev tswj hwm coarse austenitic grain qauv (feem ntau ASTM 5 lossis coarser). Qhov no yog qhov tseem ceeb rau lub sijhawm ntev -lub sij hawm creep resistance.
Kev Ua Haujlwm Zoo rau Petrochemical Rauv: Cov khoom xws li tawg rauv tube hangers, pigtails, qhov hluav taws xob manifolds, thiab cov raj radiant ua haujlwm tsis tu ncua ntawm 1600-2000℃F (870-}1095 degree) rau xyoo nyob rau hauv qhov tseem ceeb load. Lub hom phiaj tseem ceeb tsis ua hauj lwm yog creep rupture. Cov qauv ntawm cov pob zeb ntxhib ntawm 800HT txo qis qhov ciam teb zawv zawg- cov txheej txheem nkag siab tseem ceeb ntawm cov ntsuas kub no-yog li ncua sij hawm- mus rau - tawg los ntawm kev txiav txim siab piv rau cov khoom zoo. Qhov no txhais tau ncaj qha mus rau qhov ntev ntev (feem ntau 6-10 xyoo) ntawm kev kaw kaw, ua kom cov nroj tsuag muaj txiaj ntsig zoo. Vim li no, 800HT yog cov khoom siv codified hauv ASME Boiler thiab Pressure Vessel Code, Tshooj I, rau qhov kub-kub qhov chaw, nrog rau qhov muaj txiaj ntsig kev ntxhov siab tau lees paub txog 1500℃F (815 degree).
2. Nyob rau hauv ethylene cracking thiab chav kho qhov cub, dab tsi tshwj xeeb degradation mechanisms Incoloy 800HT phaj tiv taus, thiab nws cov metallurgy muab kev tiv thaiv li cas?
Sab hauv ntawm lub pyrolysis los yog kev hloov kho qhov cub yog ib qho ntawm qhov hnyav tshaj plaws - qhov kub thiab txias ib puag ncig hauv kev lag luam . 800HT yog tsim los tiv thaiv kev sib koom ua ke ntawm kev hem thawj:
Creep Deformation & Rupture: Raws li saum toj no, cov qauv ntxhib ntxhib thiab ruaj khov carbide chemistry muab kev tiv thaiv tseem ceeb rau lub sijhawm- nyob ntawm deformation nyob rau hauv kev ntxhov siab.
Carburization: Cov txheej txheem roj (hydrocarbons) yog carburizing heev. Cov pa roj carbon atoms tuaj yeem tawg mus rau hauv cov hlau, tsim cov chromium carbides sab hauv. Qhov no ua rau embrittlement, volumetric o ("loj"), thiab poob ntawm oxidation tsis kam.
Kev Tiv Thaiv: Lub siab, ruaj khov nickel cov ntsiab lus (~ 32%) txo qis carbon solubility thiab diffusivity. Qhov tseem ceeb tshaj, cov txhuas thiab titanium nyiam tsim cov txheej tuab, txuas ntxiv sab hauv ntawm Al₂O₃ thiab TiO₂ hauv qab thawj Cr₂O₃ nplai. Qhov no ua rau muaj kev cuam tshuam zoo heev rau cov pa roj carbon ingress, cov khoom muaj txiaj ntsig zoo dua rau ntau dua -nickel alloys yam tsis muaj cov khoom ntxiv no.
Hlau Plua plav: Ib daim ntawv loj heev ntawm corrosion nyob rau hauv carbon{0}}supersaturated gases (CO/H₂) ntawm 800-1600℃F (430-870 degree), ua rau pitting thiab disintegration rau graphite thiab hlau hmoov av.
Kev Tiv Thaiv: Tib qhov kev tiv thaiv oxide nplai uas tiv thaiv carburization yog thawj kab ntawm kev tiv thaiv. Rau cov khoom nyob rau hauv qhov ntsuas kub tseem ceeb (xws li, cov kab hloov pauv), 800HT feem ntau tau teev tseg nrog cov txheej txheem aluminide diffusion (Alonizing®) los ua ib qho kev tiv thaiv alumina ntau dua.
Oxidation & Cyclic Oxidation: Siab -kub cov pa roj thiab cov nkev ua rau saum npoo. Thermal cycling tuaj yeem ua rau scale spallation, ua rau cov hlau tsis zoo.
Kev Tiv Thaiv: Lub 21% chromium tsim ib tug tenacious Cr₂O₃ nplai. Cov txhuas txhim kho nplai adhesion thiab nws tus kheej- kho muaj peev xwm, ua kom muaj kev tiv thaiv zoo thaum rov pib dua- nce / kaw.
3. Rau fabricating lub cub tawg loj ntawm A424 phaj (piv txwv li, qhov hluav taws xob headers), dab tsi yog qhov tseem ceeb welding thiab post-weld cov txheej txheem los khaws cov alloy lub siab- kub khoom?
Fabrication ntawm 800HT Cheebtsam yog ib qho kev ua haujlwm siab -, raws li kev vuam tsis zoo tuaj yeem rhuav tshem cov txheej txheem ua tib zoo ua cov pob zeb ntxhib thiab cov carbide faib rau hauv tshav kub- thaj chaw cuam tshuam (HAZ).
Vuam txheej txheem & Filler Hlau: Gas Tungsten Arc Vuam (GTAW/TIG) yog tus qauv kub rau hauv paus thiab kub dhau vim muaj kev tswj hwm zoo. Shielded Hlau Arc Vuam (SMAW) lossis Gas Metal Arc Vuam (GMAW) tuaj yeem siv los sau. Cov hlau muab tub lim yuav tsum yog tag nrho.
Kev xaiv thawj zaug: ERNiCr-3 (Inconel 625 muab tub lim). Qhov no yog yuav luag universally teev. Nws cov molybdenum siab thiab niobium cov ntsiab lus muab superior as-welded zog thiab tsis kam mus rau HAZ fissuring. Cov hlau weld kuj muaj cov ductility zoo heev thiab thermal qaug zog ua haujlwm.
Lwm txoj kev: ERNiCrCoMo-1 (Inconel 617 muab tub lim). Siv rau cov ntawv thov uas xav tau tshaj plaws uas yuav tsum tau muaj qhov kub siab tshaj plaws hauv qhov vuam.
Critical Welding Parameters:
Tsawg Kub Input: Siv qhov tsawg kawg nkaus amperage thiab voltage tsim nyog. Stringer hlaws yog nyiam dua weaving.
Interpass Temperature Control: nruj me ntsis tswj<250°F (120°C). This prevents excessive grain growth in the HAZ and controls the precipitation of detrimental phases.
Ua ntej-weld huv huv: Tshem tawm tag nrho cov kab mob (roj, roj, xim, cim) kom tsis txhob kub tawg.
Tshaj tawm -Kev Kho Hniav Kub Kub (PWHT): Qhov no yog qhov kev txiav txim siab nyuaj thiab tseem ceeb.
Tag Nrho Cov Tshuaj Annealing (2100℃F +) yog qhov zoo tshaj plaws los kho cov qauv ntxhib ntxhib thiab cov khoom zoo. Txawm li cas los xij, nws yog feem ntau impractical rau loj, complex fabrications vim lub cub tawg loj txwv thiab kev pheej hmoo ntawm distortion.
Kev Ua Lag Luam: Rau ntau yam tseem ceeb xws li headers, sub-kev daws teeb meem "re-stabilization" lossis "re-age" kev kho cua sov yog ua. Qhov no suav nrog cua sov rau 1650-1750℃F (900-955 degree), uas:
Re-dissols tej teeb meem chromium carbides uas tej zaum yuav tau tsim nyob rau hauv HAZ.
Tso cai rau cov titanium thiab txhuas rov ua dua -precipitate raws li muaj txiaj ntsig, stabilizing carbides / nitrides.
Relieves residual stresses tsis ua rau cov qoob loo ntau dhau.
Lub voj voog PWHT tshwj xeeb yog muab los ntawm cov txheej txheem vuam tsim nyog (WPS) thiab tsis yog - sib tham tau rau kev tuav lub neej tsim.
4. Kev ua tau zoo thiab tus nqi li cas -Qhov txiaj ntsig ntawm Incoloy 800HT phaj piv rau lwm cov khoom siv hluav taws xob zoo li HK-40 cam khwb cia hlau thiab RA 330?
Kev xaiv cov khoom siv rau cov raj xaim hluav taws xob thiab lwm qhov cub hluav taws xob sab hauv yog qhov sib npaug ntawm tus nqi pib, tus nqi tsim khoom, thiab kev cia siab rau lub neej.
vs. Centrifugally Cast HK-40 (Fe-25Cr-20Ni):
HK-40 yog cov cam khwb cia hlau, ib txwm siv rau cov raj radiant. Nws yog qis dua hauv cov khoom siv thawj zaug.
Kev ua tau zoo: 800HT (wrought) muaj ntau dua creep zog, zoo dua ductility, thiab superior weldability. HK-40 tubes yog nkig ntau, nws yooj yim rau casting qhov tsis xws luag, thiab nyuaj kho. Lawv lub zog qis dua feem ntau xav tau cov phab ntsa tuab, txo cov thermal efficiency.
Tus nqi ntawm lub neej: Thaum pheej yig dua, HK-40 raj feem ntau muaj lub neej ua haujlwm luv dua (3-5 xyoos) piv rau 800HT raj (6-10+ xyoo). Qhov kev sib tw ntev ntev ntawm 800HT, nrog kev hloov pauv tsis tu ncua, feem ntau ua rau nws siv nyiaj ntau dua lub neej ntawm lub cub tawg. Cov qauv hauv cov qauv tsim hluav taws xob niaj hnub no muaj zog rau cov hlau nplaum zoo li 800HT.
vs Wrought RA 330 (UNS N08330):
RA 330 yog qhov tseem ceeb tshaj plaws, cov khoom siv - kev daws teeb meem muaj zog alloy (35Ni-19Cr) nrog cov carburization zoo heev thiab thermal qaug zog.
Kev ua tau zoo: 800HT excels nyob rau hauv siab ntshiab -kub creep zog saum ~ 1800℃F (980 degree) vim nws cov ntxhib grain qauv. RA 330 tej zaum yuav muaj qhov zoo dua nyob rau hauv qhov hnyav heev, cyclic carburizing / oxidizing ib puag ncig ntawm qhov kub qis dua vim nws cov ntsiab lus ntau dua nickel.
Daim ntawv sib cais: 800HT yog qhov zoo dua rau kev thauj khoom hnyav, siab - qhov kub ntawm cov khoom siv xws li lub raj hangers thiab cov tshuab txhawb nqa qhov twg nkag yog qhov tseem ceeb tsim qauv. RA 330 feem ntau yog xaiv rau pob tawb, tais, thiab cov raj radiant nyob rau hauv tshav kub-kho qhov cub uas thermal cycling hnyav dua. Hauv ethylene furnaces, 800HT yog tus qauv rau qhov kub tshaj plaws, feem ntau tseem ceeb.
5. Dab tsi tshwj xeeb kev pov hwm zoo thiab cov kev xeem yuav tsum yog qhov tseem ceeb thaum muab ASTM A424 800HT phaj rau daim ntawv thov qhov tseem ceeb?
Kev yuav cov phaj rau cov cai-stamped siab qhov chaw (ASME) lossis cov khoom siv hluav taws xob tseem ceeb yuav tsum tau muaj kev pov thawj dhau ntawm tus qauv Mill Test Report (MTR).
Cov ntaub ntawv yuav tsum tau (ASTM A424 Yam tsawg kawg nkaus):
Thaum tshav kub kub/Cast Number Traceability.
Daim Ntawv Qhia Tshuaj Ntsuam Xyuas: Tshawb xyuas C, Al, Ti thiab (Ti + Al) / C Ntau dua lossis sib npaug rau 12 qhov sib piv. Qhov no yog qhov kev txheeb xyuas rau 800HT vs . 800H.
Mechanical Test Report: Tensile thiab yield zog, elongation los ntawm cov kev ntsuam xyuas ua nyob rau hauv cov ntaub ntawv los ntawm raws li - xa (tshuaj annealed) mob.
Grain Size Report: Daim ntawv pov thawj hais tias lub phaj yog tov annealed ntawm ntau dua los yog sib npaug rau 2100℃F thiab cov txiaj ntsig loj raws li qhov tshwj xeeb (feem ntau ASTM 5 lossis coarser).
Cov Kev Xav Tau Ntxiv (Ntse Invoked):
S1. Kev kuaj ultrasonic: 100% UT ib ASTM A578 / A20 yog ib qho rau cov phaj tuab kom ntseeg tau tias muaj suab nrov thiab tsis muaj laminations.
Creep thiab/los yog Kev Nyuaj Siab-Rupture Testing: Rau cov ntawv thov tseem ceeb tshaj plaws, tus neeg yuav khoom yuav xav tau kev kuaj xyuas cov qauv los ntawm cov cua sov kom paub tseeb tias nws ua tau raws li qhov tsawg kawg nkaus lub neej tawg (piv txwv li, 1000 teev) ntawm qhov kev ntxhov siab thiab qhov kub thiab txias (xws li 1800℃F).
Kev Tshawb Fawb Hardness: txhawm rau txheeb xyuas qhov kev kho cua sov tsis sib xws thoob plaws lub phaj.
Thib peb-Kev Tshuaj Xyuas Ib Tug (TPI): Nws yog tus qauv kev coj ua rau kawg- cov neeg siv lossis Engineering, Procurement, thiab Construction (EPC) cov tuam txhab los koom nrog tus thib peb- tus neeg soj ntsuam rau:
Ua tim khawv zaum kawg ntawm lub zeb.
Tshawb xyuas thiab lees paub tag nrho cov ntaub ntawv.
Txheeb xyuas cov khoom siv thiab cim.
Xyuas kom muaj kev ntim khoom kom zoo los tiv thaiv kev puas tsuaj ntawm qhov chaw (s khawb, kab mob hlau) thaum xa khoom.
Cov txheej txheem QA nruj no ua kom lub phaj xa mus rau tus neeg tsim khoom muaj cov khoom tsim nyog uas yuav tsum tau ua kom tiav xyoo caum- lub neej tsim ntev uas xav tau nyob rau hauv lub tshuab hluav taws xob niaj hnub no.
