Q1: Dab tsi yog qhov sib txawv ntawm kev xaj ib lub bar rau ASTM B574 UNS N10276 piv rau kev txiav txim rau W.Nr. 2.4819? Puas yog lawv interchangeable?
Teb:
Los ntawm ib qho kev taw qhia metallurgical, lawv yog cov khoom tseem ceeb tib yam, tab sis qhov sib txawv yog nyob rau hauv lub regional specification system thiab cov kev lees paub.
W.Nr. 2.4819 yog Werkstoffnummer (cov ntaub ntawv naj npawb) uas tau muab los ntawm German Lub Tsev Haujlwm rau Standardization (DIN) raws li European cov ntaub ntawv tus lej lej. Nws sib raug ncaj qha rau cov tshuaj muaj pes tsawg leeg txwv ntawm UNS N10276 (Hastelloy C-276).
Interchangeability:
Yog lawm, lawv feem ntau suav hais tias hloov pauv tau ntawm chemistry. Ib daim ntawv pov thawj raws li UNS N10276 yuav ua tau raws li qhov txwv tsis pub muaj rau W.Nr. 2.4819, thiab rov ua dua. Ob leeg xa mus rau tib lub Nickel-Chromium-Molybdenum alloy nrog tungsten.
Qhov Tseem Ceeb Qhov txawv:
Chemical Composition Tolerances: Thaum cov ntsiab lus tseem ceeb (Ni, Cr, Mo, W) ua raws, European (ISO / DIN) cov qauv qee zaum muaj kev txwv nruj dua ntawm cov khoom seem xws li Cobalt lossis Manganese piv rau ASTM tus qauv. Thaum xaj, koj yuav tsum qhia seb koj puas xav tau raws li "W.Nr." txwv lossis "ASTM" txwv.
Kev Ntsuas thiab Cov Ntaub Ntawv: ASTM B574 tsom hnyav rau kev ntsuas kev siv tshuab (tensile, yield) thiab qhov ntev ntev ntev rau nti- phaus lossis ntau qhov US. Cov qauv European (xws li EN 10095 lossis cov lej tshwj xeeb AD2000) yuav xav tau ntau qhov kev xeem sib txawv lossis hom ntawv pov thawj tshwj xeeb (xws li EN 10204 3.1 vs. 3.2).
Kev Siv Kev Lag Luam: Hauv North America thiab Asia -Pacific roj thiab roj, ASTM B574 yog qhov tseem ceeb tshaj plaws. Hauv European cov nroj tsuag tshuaj, tsheb, lossis kev tsim cov hlab ntsha siab (PED), cov kws ua haujlwm feem ntau ua rau W.Nr. 2.4819.
Xaus: Thaum cov hlau zoo ib yam, lawv tsis tuaj yeem hloov pauv yam tsis muaj tus ntoo khaub lig- cov lus qhia hauv engineering specification. Nco ntsoov xyuas seb qhov project ua raws li ASTM / ASME lossis ISO / EN cov lej.
Q2: Vim li cas W.Nr. 2.4819 feem ntau yog "mus- mus" cov khoom siv rau cov ntaub ntawv reactor thiab cov hlab ntsha tuav ob qho tib si hydrochloric acid thiab ferric chlorides?
Teb:
Kev xaiv ntawm W.Nr. 2.4819 rau kev tuav cov kua qaub sib xyaw xws li HCl thiab oxidizing ntsev (FeCl₃) los rau nws lub peev xwm tshwj xeeb los tswj ob qhov oxidizing/txo ib puag ncig yam tsis muaj txheej txheej dhau los.
Cov ntaub ntawv feem ntau ua tsis tau nyob rau hauv cov cheeb tsam no vim yog ib qho kev txhim kho corrosion. Stainless hlau cia siab rau txheej chromium oxide. Hauv kev txo cov kua qaub (HCl), cov txheej ntawd dissolves. Hauv oxidizing chlorides (FeCl₃), stainless hlau tuaj yeem raug kev txom nyem los ntawm "riam- kab" nres lossis pitting.
W.Nr. 2.4819 vam meej ntawm no vim:
Molybdenum (15-17%): Muab kev tiv thaiv tshwj xeeb los txo cov kua qaub xws li hydrochloric acid. Nws tso cai rau cov hlau nyob ruaj khov txawm tias cov yeeb yaj kiab passive raug txo qis.
Chromium (14.5-16.5%): tuav cov oxidizing xwm ntawm ferric ions (Fe³⁺). Cov chromium ua kom ntseeg tau tias yog tias cov kua qaub txo qis rau ntawm qhov chaw, cov tshuaj oxidizing (FeCl₃) tam sim ntawd pab rov qab rau nws.
Nickel Matrix: Cov ntsiab lus siab nickel (sib npaug) tiv thaiv chloride kev ntxhov siab corrosion tawg, uas yuav yog kev tuag rau cov qauv stainless hlau hauv cov kev daws teeb meem kub FeCl₃.
Hauv qhov tseem ceeb, W.Nr. 2.4819 ua raws li "universal solvent resistant" cov ntaub ntawv nyob rau hauv cov kwj sib xyaw, whereas high -kev ua tau zoo duplex lossis super- austenitic yuav ua tau zoo nyob rau hauv ib qho tab sis ua tsis tau zoo nyob rau lwm qhov.
Q3: Thaum fabricating Cheebtsam los ntawm W.Nr. 2.4819 tuav, dab tsi tshwj xeeb teeb meem tshwm sim thaum lub sij hawm txias ua hauj lwm (khoov los yog tsim), thiab lawv yuav txo tau li cas?
Teb:
W.Nr. 2.4819 qhia txog kev ua haujlwm siab heev, uas yog siab dua li ntawm austenitic stainless hlau zoo li 304 lossis 316. Qhov no nthuav tawm cov teeb meem tshwj xeeb thaum lub caij txias txias.
Qhov Kev Sib Tw:
Thaum koj khoov los yog tsim ib lub bar ntawm 2.4819, cov khoom hardens sai heev ntawm qhov deformation. Yog tias koj sim ua txuas ntxiv yam tsis tau hais txog qhov no, koj pheej hmoo ib yam ntawm ob yam:
Cracking: Cov khoom siv nws cov ductility thiab tawg.
Caij nplooj ntoos hlav-rov qab: Lub zog tawm los siab (uas nce siab heev nrog kev ua haujlwm txias) ua rau lub caij nplooj ntoos hlav rov qab hnyav, ua rau kev tswj xyuas qhov nyuaj.
Mitigation Strategies:
Cov khoom siv ntau dua: Cov khoom siv yuav tsum tau ntsuas rau cov tonnage ntau dua li cov pa roj carbon steel lossis cov qauv stainless hlau.
Intermediate Annealing: Rau kev khoov hnyav lossis ntau-theem tsim, lub bar yuav tsum tau rov ua dua - kev daws teeb meem (feem ntau nyob ib ncig ntawm 1120℃/ 2050℃F) kom soften txoj haujlwm- hardened qauv ua ntej txuas ntxiv.
Lubrication: Heavy-lub luag hauj lwm lubricants yuav tsum tau tiv thaiv galling (ib qho teeb meem tshwm sim nrog npib tsib xee alloys) ntawm qhov bar thiab qhov tuag.
Relaxed Radii: Cov kws ua haujlwm feem ntau qhia txog qhov khoov radii loj dua rau 2.4819 piv rau cov hlau tsis muaj steel kom faib cov kab mob hla thaj tsam dav dua thiab txo qhov ua haujlwm siab tshaj plaws.
Q4: Peb tab tom machining lub precision valve qia los ntawm W.Nr. 2.4819 bar Tshuag. Vim li cas peb thiaj li muaj qhov hnyav "tsim- nce ntug" (BUE) ntawm peb cov cuab yeej, thiab peb yuav kho nws li cas?
Teb:
Lub "Ua-Up Ntug" (BUE) koj tab tom ntsib yog cov tsos mob classic ntawm machining npib tsib xee-raws li alloys xws li 2.4819. Nws tshwm sim vim hais tias cov khoom muaj siab ductility thiab tensile lub zog, ua ke nrog tsawg thermal conductivity.
Vim li cas BUE tshwm sim:
Thaum tshav kub kub Retention: Tsis zoo li cov hlau, uas nqa cov cua sov tawm ntawm lub nti, 2.4819 khaws cov cua sov hauv thaj tsam txiav. Qhov kub siab no, ua ke nrog kev kub siab, ua rau cov khoom siv nti los txuas nws tus kheej mus rau qhov txiav ntawm lub cuab yeej.
Adhesion: Nickel alloys muaj lub ntuj tsim los ua raws li cov khoom siv hauv siab thiab kub. Raws li qhov ua tau - nce ntug loj tuaj, nws hloov cov cuab yeej geometry, ua rau lub ntsej muag tsis zoo thiab qhov kawg ntawm cov cuab yeej tawg.
Qhov Kho:
Txheej Txheej: Hloov mus rau cov cuab yeej nrog PVD siab heev (Lub Cev Vapor Deposition) txheej zoo li AlCrN (Aluminium Chromium Nitride) lossis TiAlN. Cov no ua raws li thermal barriers thiab txo cov tshuaj affinity ntawm cov nti thiab cov cuab yeej.
Txiav ceev: Txo qhov nrawm nrawm (SFM). Kev khiav ceev dhau ua kom muaj cua sov ntau dhau uas txhawb kev vuam. Hloov pauv, khiav qeeb dhau ua rau ua haujlwm nyuaj. Koj yuav tsum nrhiav "qhov chaw qab zib" pom zoo los ntawm cov tuam txhab carbide rau ISO M lossis S cov ntaub ntawv.
Coolant Pressure: Siv siab -siab coolant (70 bar / 1000 psi los yog siab dua) qhia meej ntawm lub cuab yeej -chip interface. Qhov no hydraulically yuam cov nti tawm thiab txo cov cua sov, tiv thaiv cov nti los ntawm qhov ntev txaus rau vuam.
Positive Rake: Siv cov ntxig nrog cov ntse, zoo txiav geometries los txiav cov khoom kom huv si tsis yog thawb nws.
Q5: Nyob rau hauv siab -kub gaskets thiab sealing daim ntaub ntawv, vim li cas yog cov tuav ntawm W.Nr. 2.4819 feem ntau teev tshaj cheaper superalloys xws li 800H?
Teb:
Thaum xaiv cov khoom siv rau lub gasket los yog qhov tseem ceeb sealing nto (xws li lub nplhaib sib koom ua ke), qhov tseem ceeb hloov ntawm lub zog loj mus rau lub caij nplooj ntoos hlav -cov yam ntxwv rov qab, oxidation tsis kam, thiab tshuaj lom neeg sib xws ntawm qhov kub thiab txias.
Thaum Alloy 800H yog ib qho zoo heev - cov khoom siv zog rau cov tub rauv thiab cov pigtails, W.Nr. 2.4819 feem ntau nyiam cov ntsaws ruaj ruaj hauv kev ua tshuaj rau peb lub laj thawj tshwj xeeb:
Tsawg Coefficient ntawm Thermal Expansion (CTE): Nyob rau hauv kev sib txuas bolted flange, yog tias lub gasket nthuav dav thiab sib cog lus ntawm tus nqi sib txawv ntawm cov khoom flange (feem ntau stainless hlau), lub foob tuaj yeem xau thaum caij tsheb kauj vab. W.Nr. 2.4819 muaj CTE uas nyob ze rau cov hlau tsis muaj steel ntau dua li qee cov hlau-raws li superalloys, ua kom lub gasket txav nrog lub flange.
Sulfidation Resistance: Hauv refineries, siab -cov ntsaws ruaj ruaj yuav tsum tiv thaiv sulfidizing cua. Lub siab molybdenum thiab chromium cov ntsiab lus nyob rau hauv 2.4819 muab superior tiv thaiv sulfur nres piv rau cov hlau - puag ntawm 800H, uas muaj peev xwm tsim nkig hlau sulfide nplai.
Chloride Resistance: Yog tias qhov kub siab - ib puag ncig muaj cov tshuaj chlorides (uas tuaj yeem ua rau lub sijhawm kaw), 800H tuaj yeem raug kev txom nyem los ntawm pitting. W.Nr. 2.4819 tseem tiv thaiv. Vim li no, W.Nr. 2.4819 yog cov khoom siv txheem rau "RTJ" (Ntiv Nplhaib Hom Joint) gaskets hauv corrosive siab - kev pabcuam siab, txawm tias cov khoom siv kim dua piv rau 800H lossis 316.
