Hastelloy C-4 vs C-276: Thermal Stability Advantage for As-Welded Chemical Process Equipment

Hastelloy C-4 thiab C-276 yog dab tsi, thiab lawv cov khoom sib txawv li cas?

C-4 thiab C-276 sib koom yuav luag zoo tib yam chromium thiab molybdenum cov ntsiab lus (16% txhua), tab sis C-276 ntxiv 4% tungsten thiab nqa ntau cov hlau thiab cobalt, thaum C-4 ntxiv me me titanium ntxiv thiab tuav cov hlau kom nruj dua 3% siab tshaj plaws - qhov sib txawv uas zoo li me me ntawm cov ntaub ntawv thaum tshav kub kub. vuam.

Tau qhov twg los: Haynes International nominal muaj pes tsawg leeg cov ntaub ntawv rau HASTELLOY C-4 thiab C-276 alloys.

Ob lub alloys yog ultra-qis- carbon (0.01% max.) thiab ultra-low- silicon (0.08% max.) npib tsib xee-chromium-molybdenum alloys - kev sib xyaw ua ke uas thawj zaug ua C{{13} cov khoom lag luam nto moo hauv peb lub 27 Ni-Cr-Mo alloy yam tsis muaj kev cuam tshuam cov teeb meem corrosion intergranular uas tau plagued ua ntej, siab dua -carbon nickel alloys. C-4 tau tsim tom qab tshwj xeeb mus rau ib kauj ruam ntxiv: los ntawm kev tshem tawm tungsten thiab nruj cov ntsiab lus hlau, Haynes International tau tsim cov hlau alloy uas yog, hauv nws cov lus, "qhov feem ntau microstructurally ruaj khov ntawm cov khoom siv nickel-chromium-molybdenum siv dav."

Vim li cas Qhov Kev Ruaj Ntseg Ruaj Ruaj Ruaj Ruaj rau Raws li -Welded Chemical Process Equipment?

Vuam heats cov hlau nyob ib sab ntawm lub vuam - tshav kub- cuam tshuam cheeb tsam (HAZ) - mus rau qhov kub thiab txias qhov twg chromium, molybdenum, thiab tungsten tuaj yeem ua rau cov kua dej ua kua thib ob -theem hais raws li cov ciam teb, hauv zos depleting cov hlau nyob ib puag ncig ntawm nws cov kev tiv thaiv corrosion heev - qhov twg cov khoom siv feem ntau yuav nyob rau hauv nruj.

Cov txheej txheem no - feem ntau hu ua rhiab heev thaum nws tshwm sim hauv austenitic stainless hlau, thiab ntau lub npe hu ua nplej - ciam teb lossis intermetallic nag lossis daus hauv nickel alloys - tsis tas yuav yuam kev. Txhua qhov ntau- dhau weld, txhua qhov tuab- ntu kho, thiab txhua qhov chaw vuam ua tsis muaj lub cub tawg nyob ze nthuav tawm qee qhov ntim ntawm HAZ rau qhov txaus ntshai- thaj chaw kub ib puag ncig rau qee lub sijhawm.

Cov lus nug uas yog qhov tseem ceeb rau cov neeg tsim khoom thiab cov tswv cuab tam sim no tsis yog tias qhov tshwm sim tshwm sim, tab sis lub sij hawm ntau npaum li cas ntawm qhov kub thiab txias nws yuav siv sij hawm ua ntej nag lossis daus mus txog qhov tob tob. Qhov ntawd yog raws nraim li lub sijhawm -kub-sensitization (TTS) cov ntaub ntawv ntsuas, thiab nws yog ib qho tseem ceeb tshaj plaws ntawm kev sib cais C-4 los ntawm C-276 hauv kev pabcuam raws li welded.

Yuav ua li cas C-4 thiab C-276 Sib piv nyob rau hauv lub sij hawm-Tub-Sensitization Behavior?

C-4 yuav tsum tau tuav ntawm nws qhov kub tseem ceeb tshaj plaws (825℃/ 1,517℃F) rau tag nrho 2 teev ua ntej nplej - ciam teb nres mus txog qhov kev puas tsuaj 0.05 hli qhov tob hauv ASTM G28A kuaj; C-276 ncav cuag tib qhov kev puas tsuaj tom qab tsuas yog 3 feeb ntawm qhov kub thiab txias ntawm 925℃thiab 1,050℃(1,697-1,922℃F) - qhov sib txawv ntawm kwv yees li 40x nyob rau lub sijhawm muaj ua ntej muaj kev puas tsuaj.

Tau qhov twg los: Haynes International lub sij hawm-kub{1}}sensitization (T-T-S) daim ntawv qhia, HASTELLOY C-4 alloy cov ntaub ntawv ntawv, kuaj nyob rau hauv ASTM G28A boiling ferric sulfate / sulfuric acid tov.

Haynes International hais txog qhov kev lag luam no- tawm ncaj qha: "thaum lub sijhawm vuam, cov khoom siv hluav taws xob yog qhov tseem ceeb nyob rau hauv cov ntaub ntawv ntawm C-276 alloy, tab sis ntawm qhov tshwm sim me me nyob rau hauv rooj plaub ntawm C-4 alloy." Hauv cov ntsiab lus siv tau, C-276's TTS "lub qhov ntswg" - qhov ceev tshaj plaws ntawm nws cov nag lossis daus - zaum ntawm 3 feeb xwb, lub qhov rais uas ib leeg weld hla ntawm qhov tuab tuab tuaj yeem dhau los ntawm huab cua txias.

C-4 lub qhov ntswg zaum ntawm 2 teev, lub sij hawm uas zoo tib yam arc- vuam cov cua sov input qhov tseem ceeb tsis tuaj yeem ncav cuag yam tsis txhob txwm tshaj tawm, cuam tshuam rau lub cub tawg. Tias yog vim li cas C-4 feem ntau tau teev tseg rau cov tuab- ntu cov hlab ntsha, ntau- kho qhov chaw hla, thiab txhua txoj haujlwm uas tus welder lub tshav kub nkag thiab qhov ntsuas kub tsis tuaj yeem ntsuas thiab tswj kev hla dhau.

Cov Alloy twg muab qhov zoo dua hauv cheeb tsam Corrosion Resistance - Raws li -Qhov Chaw Muab Khoom?

Hauv kev daws teeb meem-annealed, unwelded mob,C276ua tau zoo tshaj C-4 ntawm tus qauv pitting thiab crevice benchmarks - nws tungsten ntxiv nce nws qhov tseem ceeb pitting kub rau 150℃piv rau C-4's 100℃- uas yog precisely lub alloying lub tswv yim uas pauv C-4 lub thermal stability kom zoo dua.

Tau qhov twg los: Haynes International tseem ceeb pitting / crevice kub cov ntaub ntawv (acidified 6% FeCl3, ASTM G48) thiab kev ntxhov siab-corrosion cracking cov ntaub ntawv (boiling 45% MgCl2, ASTM G36), HASTELLOY C-4 thiab C-276 alloy cov ntaub ntawv.

Tib tus qauv tuav hauv Haynes qhov hnyav dua "Green Death" pitting test (11.5% H2SO4 + 1.2% HCl + 1% FeCl3 + 1% CuCl2): C-4 thawj zaug qhia pitting ntawm 85℃, thaum C-276 resists pitting tag nrho cov kev daws teeb meem. Qhov no yog tsab xov xwm kev lag luam hauv nruab nrab-tawm: tungsten ntsuas tau txhim kho C-276 qhov kev tiv thaiv rau chloride-tsav pitting thiab crevice nres hauv kev daws kom raug- cov khoom siv annealed - tab sis nws kuj yog cov alloying ntxiv rau feem ntau lub luag hauj lwm rau C-276-pitation thiab ceev ceev nqaim welding-heat-input kam rau ua. Tsis yog alloy tsuas yog "zoo dua"; txhua qhov optimizes ib qho khoom sib txawv ntawm lwm tus tus nqi.

Vuam cuam tshuam li cas Corrosion Resistance hauv kev xyaum?

Haynes International luam tawm ib qho kev sib koom tes sib koom ua ke -hlau- tiv thaiv -wrought- puag- hlau corrosion sib piv tshwj xeeb rau C-276, uas qhia cov hlau weld khiav ze rau, tab sis ntsuas tau siab dua, wrought base hlau nyob rau hauv cov kua qaub tseem ceeb - 4 lub rooj tsis sib xws, tsis muaj qhov sib xws rau C tsis sensitize nyob rau hauv ib txwm welding cua sov input thiab yog li ntawd yuav tsum tsis txhob cais weld-hlau tsim nyog.

Source: Haynes International tag nrho-weld-hlau (ntau- dhau GMAW cruciform) vs. wrought puag-cov ntaub ntawv hlau corrosion, HASTELLOY C-276 alloy cov ntaub ntawv.

Qhov sib txawv ntawm C-276 lub vuam hlau thiab wrought puag hlau yog me me ntawm cov kub nruab nrab - feem ntau yog 2-4x, tsis yog kev puas tsuaj - tab sis nws yog tiag tiag, thiab nws yog vim li cas vuam txheej txheem specifications (WPS) rau C-276 siab mandate cov cuab yeej siv ntau zaus, kev sib tw kub thiab txias stringer-bead txheej txheem ntawm tuab ntu. Rau C-4, Haynes ' fabrication kev taw qhia imposes tsis muaj piv rau cov cua kub input kev qhuab qhia tshwj xeeb los tiv thaiv corrosion, vim hais tias cov alloy cov chemistry tsis muab tshav kub input lub ntsiab lus kom rub.

Yuav Ua Li Cas C-4 thiab C-276 Sib piv hauv Bulk Acid Resistance - HCl thiab Sulfuric Acid?

Haynes International piav qhia C-4 tias muaj "zoo tib yam corrosion kuj" raws li C-276, thiab qhov ntawd tuav tau zoo hauv hydrochloric acid - tab sis luam tawm cov ntaub ntawv kub sulfuric acid qhia tau hais tias C-276 nrog cov ntsiab lus qis dua corrosion, kwv yees li ib nrab ntawm C-4's, hla 10-30% concentration ntau.

Tau qhov twg los: Haynes International hydrochloric thiab sulfuric acid corrosion rooj, HASTELLOY C-4 thiab C-276 alloy cov ntaub ntawv.

Qhov no yog qhov muaj txiaj ntsig, cov ntaub ntawv - thim rov qab kho rau cov lus luv luv uas C-4 yog "tsuas yog ntau dua weldable C-276." Rau dilute - mus rau - nruab nrab boiling sulfuric acid lub luag hauj lwm tshwj xeeb, C-276 yog cov zoo-ua hlau alloy nyob rau hauv lub zoo tov-annealed los yog raug welded mob. C-4 qhov txiaj ntsig tiag tiag tsis yog cov kua qaub tsis zoo - nws yog qhov lav tias cov hlau tsis muaj zog yuav tsis degrade hauv HAZ txawm tias cov cuab yeej siv tau li cas.

Tsis yog alloy yog npaj rau kev pabcuam oxidizing acid heev: Haynes tsis tshaj tawm cov lus nitric acid rau C-4 kiag li, thiab C-276 tus kheej cov ntaub ntawv nitric acid qhia tau hais tias corrosion nqi nce siab ntawm qhov siab dua thiab kub (18.42 mm / y ntawm 60% boiling, 22.15 mm / y } yuav tsum raug txiav tawm ntawm 6. boiling, concentrated nitric acid lub luag haujlwm. Qhov twg oxidizing los yog tov nitric-acid kev pab cuam yog tus tsav tsheb, siab dua-chromium alloys xws li G-30, G-35, los yog C-22 yog qhov tsim nyog tshaj specification.

Mechanical Properties thiab Fabrication Characteristics Sib piv li cas?

C-4 thiab C-276 qhia qhov tseem ceeb ntawm tib lub zog hauv chav kawm thiab ob qho tib si tau muab rau zeb-annealed yam tsis muaj kev kho cua sov tom qab uas xav tau rau kev ua haujlwm corrosion, tab sis C-4 anneals thiab kub-forges ntawm qhov kub qis dua thiab tsis muaj li forgings, thaum C-276 yog.

Tau qhov twg los: Haynes International tensile, hardness, thiab fabrication cov ntaub ntawv, HASTELLOY C-4 thiab C-276 alloy cov ntaub ntawv.

Dab tsi yog ASTM, ASME, thiab Cov Qauv Kev Lag Luam Tswj Xyuas C-4 thiab C-276?

C-4 thiab C-276 qhia ze li ntawm ASTM / ASME cov khoom-daim ntawv qhia tshwj xeeb rau daim ntawv, bar, thiab yeeb nkab, tab sis lawv sib txawv ntawm ob lub ntsiab lus tsim nyog chij hauv qhov kev qhia tshwj xeeb: C-276 nqa ib qho tshwj xeeb forgings specifications thiab NACE MR0175 / ISO 15156 cov lus qhia tshwj xeeb hauv cov lus qhia.

Tau qhov twg los: Haynes International "Specifications and Codes" tables, HASTELLOY C-4 and C-276 alloy data sheets.

Yam Khoom Uas Koj Yuav Tsum Tau Qhia Txog Raws li -Cov Khoom Siv Tshuaj Txheej Txheem Welded?

Qhia meej C-4 qhov twg weld heat input tsis tuaj yeem ntsuas nruj thiab tswj tau - tuab-section field welds, multi- dhau kev kho, thiab khw muag khoom tsis tsim nyog tsawg- cua sov- cov txheej txheem nkag; qhia C-276 qhov twg yuav tsum tau forgings, qhov chaw vuam cov txheej txheem tsim nyog thiab cua sov- tawm tswv yim- tswj, lossis qhov twg nws qhov kub thiab txias siab dua thiab qis boiling -sulfuric-acid corrosion tus nqi xa cov txiaj ntsig kev pab cuam lub neej.

Xaiv C-4 rau:Thick -section cov hlab ntsha thiab cov kav dej uas tsim los ntawm ntau qhov kev sib txuas, qhov twg HAZ kub raug cuam tshuam yog nyuaj rau khi.

Xaiv C-4 rau:Kev kho qhov chaw vuam qhov sib cuam tshuam qhov kub thiab txias tsis tuaj yeem ntsuas thiab tswj txoj hauv kev uas lawv tuaj yeem ua tau hauv khw muag khoom.

Xaiv C-4 rau:Cov khoom siv uas yuav pom qhov tshwm sim ntawm qhov kev pabcuam raug cuam tshuam hauv 650-1050℃ntau yam (piv txwv li, nyob ze rau qhov cub lossis thaum muaj kev ntxhov siab), qhov uas tsis kam rau kev pabcuam hauv kev pabcuam tseem ceeb ntau npaum li kev sib txuas.

Xaiv C-276 rau:Forged Cheebtsam - flanges, fittings, valve lub cev - txij thaum C-276 yog ASTM B564 forgings specification thiab C-4 tsis.

Xaiv C-276 rau:Yuav khoom-fabricated cov cuab yeej uas tsim nyog, qis- cua sov- cov txheej txheem vuam cov lus qhia (WPS) thiab tswj qhov kub ntawm qhov sib txawv, qhov uas C-276 qhov kev pheej hmoo ntawm kev puas tsuaj yog tswj tau zoo.

Xaiv C-276 rau:Boiling, dilute - mus rau - nruab nrab (10-}30%) sulfuric acid kev pab cuam thiab hnyav chloride-pitting ib puag ncig, qhov twg nws ntsuas qhov corrosion qis dua thiab siab dua CPT / CCT txhais ua haujlwm ntev dua.

Xaiv C-276 rau:Sour -kev pabcuam (NACE MR0175/ISO 15156) daim ntawv thov, qhov twg C-276 nqa qhov kev tsim nyog thiab C-4 tsis.

Nyob rau hauv ob qho tib si, lub hauv paus ntsiab lus engineering yog tib yam Haynes International hais ncaj qha rau C-4: microstructural stability txiav txim siab seb qhov hluav taws xob nkag yog qhov sib txawv koj yuav tsum tswj lossis ib qho koj tuaj yeem tsis quav ntsej ntau. Qhov twg vuam tej yam kev mob tswj tau zoo, qhov sib txawv ntawm qhov teeb meem tsawg dua, thiab C-276 cov cuab yeej dav dua thiab muaj dav dua feem ntau ua rau nws muaj kev lag luam ntau dua, kev xaiv corrosion-resistant ntau dua. Qhov chaw vuam tsis tuaj yeem tswj nruj nruj, C-4 lub thermal stability tshem tawm ib qho loj tshaj plaws ntawm kev pheej hmoo corrosion.

Cov lus nug nquag

Q: Dab tsi yog qhov txawv ntawm Hastelloy C-4 thiab C-276?

A: C-276 (UNS N10276) ntxiv 4% tungsten thiab me ntsis hlau ntau dua C-4 (UNS N06455), uas muab C-276 siab dua pitting thiab crevice kuj nyob rau hauv cov tshuaj{11}}annealed mob tab sis ua rau nws deb npaum li cas rau fastpitation thaum tshav kub kub boundary. C-4 tshem tawm tungsten thiab yog, nyob rau hauv Haynes International tus kheej cov lus, feem ntau microstructurally ruaj khov ntawm cov lug siv nickel-chromium-molybdenum alloys.

Q: Vim li cas C-4 suav hais tias zoo dua rau cov khoom siv vuam zoo dua li C-276?

A: Vim tias C-4 xav tau 2 teev ntawm nws qhov ntsuas kub tseem ceeb tshaj plaws (825 degree) ua ntej qhov kev tawm tsam ntawm cov ciam teb mus txog qhov tob tob, thaum C-276 nce mus txog qhov kev puas tsuaj tib yam li 3 feeb ntawm 925-1050 degree. Qhov ntawd kwv yees li 40x qhov sib txawv txhais tau hais tias kev sib txuas hluav taws xob hluav taws xob yog qhov tseem ceeb rau C-276 tab sis qhov tshwm sim me me rau C-4.

Q: Puas yog C-4 lossis C-276 puas muaj kev tiv thaiv corrosion zoo tag nrho?

A: Tsis yog categorically zoo dua. C-276 muaj qhov tseem ceeb dua qhov kub thiab txias (150℃vs . 100℃rau C-4) thiab qis dua tus nqi corrosion nyob rau hauv boiling dilute sulfuric acid, tab sis tsuas yog welding cua sov input yog tswj. C-4 muab qhov tseem ceeb tib yam li-welded corrosion kuj raws li nws cov wrought, unwelded xeev, tsis hais txog cov txheej txheem weld.

Q: Puas yog C-4 thiab C-276 xav tau kev kho cua sov tom qab vuam?

A: Tsis yog alloy yuav tsum tau post-weld tshav kub kho rau corrosion kuj nyob rau hauv ib txwm vuam tej yam kev mob; ob qho tib si yog muab rau zeb-annealed. Txawm li cas los xij, C-276 cov txheej txheem tsim cov txheej txheem feem ntau qhia meej tswj cov khoom siv hluav taws xob thiab kev cuam tshuam ntawm qhov kub thiab txias kom tsis txhob muaj kev cuam tshuam ntawm cov ntu tuab, kev ceev faj C-4 tsis tas yuav tsum tau.

Q: Hastelloy C-4 puas siv tau qhov twg yuav tsum tau forgings?

A: Tsis yog raws li Haynes International cov lus qhia tshwj xeeb tshaj tawm, uas teev tsis muaj forgings specification rau C-4. C-276 nqa ASTM / ASME B564 / SB564 rau forgings, ua qhov kev xaiv tsim nyog rau forged fittings, flanges, thiab valve lub cev.

Q: Puas yog C-4 thiab C-276 haum rau kev pabcuam nitric acid?

A: Tsis yog. Haynes International tsis tshaj tawm cov ntaub ntawv nitric acid corrosion rau C-4, thiab luam tawm C-276 cov ntaub ntawv qhia tau hais tias corrosion tus nqi nce siab heev hauv cov concentrated, boiling nitric acid (tshaj 18 mm / y ntawm 60% boiling). Rau oxidizing lossis sib xyaw nitric-acid lub luag haujlwm, ntau dua-chromium alloys xws li G-30, G-35, lossis C-22 yog qhov zoo dua.

Q: Dab tsi vuam txheej txheem thiab muab tub lim hlau siv rau C-4 thiab C-276?

A: Ob lub alloys zoo haum rau GTAW, GMAW, thiab SMAW. C-4 siv qhov sib txuam ERNiCrMo-7 ( liab qab hlau) thiab ENiCrMo-7 (coated electrode) muab tub lim hlau; C-276 siv ERNiCrMo-4 thiab ENiCrMo-4.