Q1: Dab tsi yog qhov tseem ceeb ntawm ASTM B575 rau UNS N06200 daim hlau, thiab qhov kev qhia tshwj xeeb no txawv li cas ntawm lwm cov qauv nickel alloy phaj?
Teb:
ASTM B575 yog tus qauv tshwj xeeb rau qis-carbon nickel-chromium-molybdenum alloys phaj, ntawv, thiab sawb. Rau UNS N06200 (feem ntau hu ua Alloy 2000), qhov kev qhia tshwj xeeb no qhia txog qhov yuav tsum tau ua rau cov tshuaj muaj pes tsawg leeg, cov khoom siv kho tshuab, kev kho cua sov, thiab qhov ntev ntev.
Qhov tseem ceeb ntawm ASTM B575 rau UNS N06200:
Cov txheej txheem no ua kom ntseeg tau tias Alloy 2000 daim hlau yog tsim los nrog kev ua kom zoo ib yam, ua kom pom tseeb microstructure optimized rau corrosion kuj. Nws tau txiav txim siab tias daim hlau yuav tsum tau muab rau hauv cov tshuaj annealed mob (feem ntau nyob ib ncig ntawm 1075-1125℃/ 1970-2060℃F, ua raws li kev quenching ceev). Qhov kev kho cua sov no yog qhov tseem ceeb rau kev ua kom tiav cov theem ob thiab ua kom cov hlau tsis muaj qhov tshwj xeeb rau ob qho tib si oxidizing thiab txo cov xov xwm.
Qhov txawv ntawm Lwm Cov Qauv:
Scope: ASTM B575 tshwj xeeb npog cov khoom tiaj tus (phaj, ntawv, sawb) rau ntau yam alloys, suav nrog C-276, C-22, thiab Alloy 2000. Nws txawv ntawm ASTM B574 (uas npog cov tuav) thiab ASTM B622 (uas npog seamless yeeb nkab thiab raj).
Mechanical Property Requirements: ASTM B575 teev tshwj xeeb tensile, yield, thiab elongation yuav tsum tau rau daim ntawv phaj. Rau UNS N06200, qhov tsawg kawg nkaus tensile lub zog yog feem ntau 100 ksi (690 MPa) thiab yield zog yog 40 ksi (276 MPa) nyob rau hauv lub annealed mob.
Dimensional Tolerances: Tus qauv muab cov lus qhia ntxaws rau cov thickness, dav, ntev, thiab flatness kam rau ua tshwj xeeb rau cov khoom phaj, uas txawv ntawm cov khoom siv rau bar lossis yeeb nkab.
Kev Xeem Zaus: ASTM B575 yuav tsum muaj qee qhov kev sim ntau zaus (piv txwv li, ib qho kev ntsuas tensile ib lub tshav kub, ib qho kev ntsuas khoov ib lub tshav kub) uas tsim nyog rau kev tsim phaj.
Xaus: Thaum koj xaj UNS N06200 phaj rau ASTM B575, koj tau lees paub cov khoom siv uas ua tau raws li kev lag luam nruj- tau txais cov qauv rau corrosion- cov kev pabcuam tiv thaiv, txhawb nqa los ntawm cov khoom siv kho tshuab thiab cov txheej txheem tswj kom zoo.
Q2: Dab tsi tshwj xeeb alloying ntxiv qhov txawv UNS N06200 (Alloy 2000) los ntawm lwm yam C-tsev neeg alloys xws li C-276, thiab qhov zoo corrosion kuj lawv muab?
Teb:
UNS N06200 (Alloy 2000) sawv cev rau kev hloov pauv hauv Ni-Cr-Mo alloy tsev neeg. Thaum nws tsim los ntawm lub hauv paus ntawm cov alloys zoo li C-276, nws muaj cov alloying tshwj xeeb ntxiv uas muab nws qhov tshwj xeeb zoo hauv qee qhov chaw corrosive.
Qhov Tseem Ceeb Distinctions:
Copper Ntxiv (1.3-1.9%): Qhov no yog qhov sib txawv tseem ceeb tshaj plaws. Tsis zoo li C-276 lossis C-22, Alloy 2000 muaj cov tooj liab tswj.
Optimized Chromium (22-24%): Siab dua C-276's 14.5-16.5%, muab kev tiv thaiv zoo rau oxidizing media.
Molybdenum (15-17%): Zoo ib yam li C-276, tswj kev ua haujlwm zoo heev los txo cov kua qaub.
Corrosion Resistance Qhov zoo:
Sulfuric Acid Resistance: Qhov sib ntxiv ntawm tooj liab muab qhov ua tau zoo heev rau sulfuric acid (H₂SO₄) thoob plaws ntau qhov ntau thiab qhov kub thiab txias. Tooj liab txhawb kev tsim cov tshuaj tiv thaiv sulfate- uas muaj cov zaj duab xis nyob rau saum npoo, uas yog qhov tshwj xeeb ruaj khov hauv kev txo cov sulfuric acid ib puag ncig uas lwm cov alloys yuav nquag yaj.
Hydrofluoric Acid Resistance: Alloy 2000 nthuav tawm kev ua haujlwm zoo tshaj rau hydrofluoric acid (HF) piv rau C-276. Qhov sib ntxiv ntawm tooj liab pab kom ruaj khov ntawm qhov chaw hauv HF ib puag ncig, txo tus nqi corrosion ntau heev.
Oxidizing/Reduction Versatility: Nrog ntau dua chromium rau oxidizing tsis kam thiab molybdenum / tooj liab rau txo tsis kam, Alloy 2000 ua tiav qhov tshwj xeeb tshuav. Nws ua tau zoo hauv cov kua qaub sib xyaw uas muaj ob hom oxidizing (xws li ferric lossis cupric ions) thiab txo cov kua qaub.
Localized Corrosion Resistance: Qhov zoo tshaj plaws chemistry muab kev tiv thaiv zoo heev rau pitting thiab crevice corrosion nyob rau hauv chloride-muaj ib puag ncig, feem ntau tshaj C-276 hauv cov xov xwm tshwj xeeb.
Kev lag luam-tawm: Alloy 2000 feem ntau kim dua C-276. Txawm li cas los xij, nyob rau hauv ib puag ncig uas nws qhov tshwj xeeb tooj liab-txhim kho qhov tsis kam muab kev pab cuam lub neej ntev dua, cov nqi siv hluav taws xob muaj peev xwm ua tau zoo heev.
Q3: Hauv kev tsim cov phosphoric acid los ntawm cov txheej txheem ntub dej, yog vim li cas ASTM B575 UNS N06200 phaj feem ntau teev rau reactor agitators thiab evaporator Cheebtsam?
Teb:
"Cov txheej txheem ntub dej" rau kev tsim cov phosphoric acid suav nrog reacting phosphate pob zeb nrog sulfuric acid, tsim kom muaj ib qho chaw corrosive heev uas muaj phosphoric acid, sulfuric acid, hydrofluoric acid (los ntawm fluoride impurities), thiab chloride ions. Qhov sib xyaw ua ke no ua rau muaj kev puas tsuaj rau ntau cov ntaub ntawv, uas yog vim li cas Alloy 2000 tau dhau los ua kev xaiv.
Yog vim li cas Alloy 2000 Excels nyob rau hauv ntub txheej txheem phosphoric acid:
Fluoride Resistance: Phosphate pob zeb feem ntau muaj fluorapatite, uas tso tawm hydrofluoric acid (HF) thiab fluorosilicic acid thaum zom. Cov tooj liab hauv Alloy 2000 muab kev tiv thaiv zoo rau HF nres piv rau tooj liab -dawb alloys xws li C-276.
Sulfuric Acid Resistance: Cov txheej txheem siv cov concentrated sulfuric acid los zom cov pob zeb. Alloy 2000's tooj liab- txhim kho kev ua tau zoo hauv sulfuric acid ua rau nws zoo tagnrho rau cov cheeb tsam tshuaj tiv thaiv thawj zaug.
Chloride kam rau ua: Cov txheej txheem ntub dej phosphoric acid feem ntau muaj cov chlorides los ntawm cov pob zeb lossis cov txheej txheem dej. Alloy 2000's siab chromium thiab molybdenum cov ntsiab lus muab kev tiv thaiv zoo rau chloride-induced pitting thiab crevice corrosion.
Abrasion-Kev Tiv Thaiv Kev Tshaj Tawm: Cov evaporator Cheebtsam thiab cov agitators nyob rau hauv phosphoric acid kev pab cuam fim cov khoom (gypsum, unreacted pob zeb). Alloy 2000 lub zog thiab ua haujlwm hardening yam ntxwv muab kev tiv thaiv zoo rau kev yaig-corrosion.
Cov khoom siv -Specific Applications:
Agitators: Cov agitator hniav thiab shafts yuav tsum tiv thaiv corrosion thiab mechanical stress. Alloy 2000 kev sib xyaw ua ke ntawm lub zog thiab kev tiv thaiv corrosion ua rau nws zoo tagnrho rau cov dynamic Cheebtsam.
Evaporator Tubes thiab Lub Cev: Nyob rau hauv theem concentration, phosphoric acid yog rhuab kom tshem tawm dej, ua kom cov kua qaub concentration thiab corrosivity. Alloy 2000 daim hlau yog siv rau cov evaporator lub cev thiab cov ntawv raj uas kub thiab concentrated acid xav tau siab tshaj corrosion kuj.
Kev sib piv kev ua tau zoo: Cov kev paub dhau los tau qhia tias Alloy 2000 tuaj yeem siv sijhawm ntev dua li cov hlau tsis muaj steel lossis lwm cov nickel alloys hauv kev pabcuam phosphoric acid, txo qis sijhawm thiab hloov cov nqi hauv cov txheej txheem txuas ntxiv.
Q4: Yuav ua li cas lub formability ntawm ASTM B575 UNS N06200 phaj piv rau austenitic stainless hlau, thiab cov tswv yim dab tsi yuav tsum tau ua kom muaj kev vam meej txias ntawm cov hlab ntsha?
Teb:
UNS N06200, zoo li lwm yam npib tsib xee-raws li alloys, nthuav tawm cov yam ntxwv sib txawv piv rau austenitic stainless hlau xws li 304L lossis 316L. Kev nkag siab txog qhov sib txawv no yog qhov tseem ceeb rau kev ua tiav ntawm cov khoom siv hauv nkoj los ntawm ASTM B575 phaj.
Kev sib piv Formability:
Ua Haujlwm Hardening Rate: Alloy 2000 muaj kev ua haujlwm siab dua li austenitic stainless hlau. Qhov no txhais tau hais tias nws yuav muaj zog thiab nyuaj dua sai dua thaum lub sij hawm tsim, yuav tsum muaj kev sib sau ntau dua.
Ductility: Thaum Alloy 2000 yog ductile (feem ntau 45% tsawg kawg elongation nyob rau hauv annealed mob), nws yog tsawg dua ductile tshaj 304L stainless hlau (uas feem ntau tshaj 50% elongation).
Caij nplooj ntoos hlav-rov qab: Vim nws lub zog tawm los ntau dua thiab ua haujlwm hnyav, Alloy 2000 nthuav tawm lub caij nplooj ntoo hlav ntau dua -rov qab dua li cov hlau tsis muaj steel. Kev tuag thiab cov cuab yeej tsim khoom yuav tsum tau them nyiaj rau qhov no.
Txoj Kev Ua Tau Zoo:
Kev Sib Tw Siab Tshaj: Cov xovxwm nres thiab cov khoom siv dov yuav tsum tau ntsuas rau cov tonnage ntau dua li qhov sib npaug ntawm cov thicknesses ntawm carbon lossis stainless hlau.
Slower Forming Speeds: Txo kev sib sau ceev tso cai rau cov khoom faib tawm kom sib npaug thiab txo qhov kev pheej hmoo ntawm kev sib tsoo los yog tawg.
Generous Bend Radii: Rau qhov khoov hnyav, qhov tsawg kawg yog khoov lub vojvoog ntawm 2-3 zaug lub phaj tuab feem ntau pom zoo (piv rau 1-2 zaug rau stainless hlau). Tighter radii ua rau muaj kev pheej hmoo ntawm kev tawg.
Intermediate Annealing: Rau cov duab nyuaj uas muaj ntau txoj hauv kev los yog deformation loj, cov tshuaj nruab nrab annealing yuav tsum tau los kho cov ductility thiab tshem tawm cov teebmeem ua haujlwm.
Lubrication: Siab- lubricants zoo yog qhov tseem ceeb los tiv thaiv kev sib tsoo ntawm cov hlau thiab cov txheej txheem tuag. Nickel alloys muaj lub siab nyiam rau gall (adhere thiab kua muag) nyob rau hauv siab.
Kev txiav txim siab kub: Thaum Alloy 2000 tuaj yeem ua kom sov kom txo tau cov rog, yuav tsum tau ceev faj tswj qhov kub thiab txias kom tsis txhob nkag mus rau qhov rhiab heev (595-815℃/ 1100-1500℃F) qhov twg cov theem detrimental tuaj yeem los nag.
Q5: Dab tsi welding muab tub lim hlau thiab cov tswv yim pom zoo rau kev koom nrog ASTM B575 UNS N06200 daim hlau kom muaj kev tiv thaiv corrosion nyob rau hauv raws li -welded mob?
Teb:
Kev tuav lub corrosion kuj ntawm Alloy 2000 nyob rau hauv welded fabrications yuav tsum tau ceev faj saib xyuas rau muab tub lim xaiv hlau thiab vuam tsis. Lub hom phiaj yog los tsim ib lub vuam nrog corrosion kuj txuam nrog lub hauv paus phaj.
Filler Hlau Xaiv:
Cov qauv kev pom zoo yog siv cov khoom sib xyaw ua ke cov hlau:
ERNiCrMo-17 (AWS A5.14): Nov yog cov hlau tshwj xeeb uas tsim los rau UNS N06200. Nws phim lub hauv paus hlau chemistry, nrog rau qhov tseem ceeb tooj liab ntxiv uas muab Alloy 2000 qhov tshwj xeeb corrosion kuj.
Alternative Fillers: Hauv qee kis, ERNiCrMo-10 lossis ERNiCrMo-13 yuav raug txiav txim siab, tab sis tsuas yog ERNiCrMo-17 khaws cov tooj liab-txhim kho kev ua tau zoo hauv sulfuric thiab hydrofluoric acid ib puag ncig.
Cov txheej txheem vuam:
Low Heat Input: Siv cov khoom siv hluav taws xob qis tshaj plaws uas siv tau thaum tuav cov fusion zoo. Kev siv hluav taws xob ntau dhau ua rau muaj kev pheej hmoo ntawm kev sib cais ntawm lub hauv paus thiab thib ob -theem nag lossis daus hauv cov hlau vuam thiab HAZ.
Interpass Temperature Control: Khaws qhov ntsuas kub hauv qab 150℃(300℃F). Tso cai rau cov weld kom txias tag nrho ntawm qhov kev hla minimizes lub sijhawm ntawm qhov kub thiab txias thiab txo qhov kev pheej hmoo ntawm nag lossis daus.
Shielding Gas: Rau GTAW (TIG) thiab GMAW (MIG), siv argon lossis argon-helium sib tov. Helium ntxiv tuaj yeem txhim kho cov ntub dej thiab ntws yam tsis muaj cua sov nkag ntau dhau. Rov qab-purging nrog argon yog qhov tseem ceeb rau cov hauv paus hniav kom tiv thaiv oxidation thiab chromium depletion.
Stringer Bead Technique: Siv stringer hlaws dai (nqaim, ncaj hla) es tsis yog xaws. Qhov no minimizes tag nrho cov cua sov input mus rau hauv paus khoom.
Tom qab-Kev Tu Vaj Tsev: Kev tu txhua yam lossis tshuaj ntxuav yuav tsum tau tshem tawm cov cua sov thiab cov oxide txheej. Cov chromium- cov txheej txheem depleted no muaj kev cuam tshuam rau qhov chaw xeb thiab yuav tsum tau muab tshem tawm los ntawm kev sib tsoo, txhuam hlau (nrog cov txhuam hlau tsis xeb tshwj xeeb rau cov nickel alloys), los yog pickling.
Ncej -Kev kho cua sov:
Rau feem ntau corrosive ib puag ncig, Alloy 2000 tuaj yeem siv raws li -welded condition. Txawm li cas los xij, rau cov kev pabcuam hnyav tshaj plaws (xws li cov kua qaub kub sulfuric acid), kev tshaj tawm -weld tov anneal (1075-1125℃/ 1970-2060℃F, ceev quench) yuav raug teev los xyuas kom zoo corrosion kuj. Kev kho qhov kub thiab txias nruab nrab yuav tsum tau zam vim tias lawv tuaj yeem ua rau muaj kev puas tsuaj rau theem nag lossis daus.
