Hastelloy B2 vs B3: Thermal Stability Txhim Kho rau Hydrochloric Acid Service

Hastelloy B-3yog B-2 nrog cov teeb meem embrittlement engineered tawm. Tswj chromium (1.0-3.0%), hlau (1.0-3.0%) thiab carbon tuav ntawm 0.01% siab tshaj plaws qeeb nag lossis daus ntawm brittle Ni4Mo beta theem.

Hauv Hastelloy B-2, Ni4Mo pib tsim nyob rau hauv feeb nyob ib ncig ntawm 700-870 degrees Celsius, nrog ceev tshaj kinetics ze 750 degrees Celsius. B-3 xav tau ob peb teev nyob ze 650 degrees Celsius ua ntej qhov kev tshem tawm thib ob tshwm sim, thiab theem uas thaum kawg tsim yog qhov qeeb qeeb-loj hlob Ni3Mo.

Ob lub alloys xa cov nqi corrosion qis dua 0.1 hli / xyoo hauv cov ntshiab hydrochloric acid txog li 70 degrees Celsius ntawm txhua qhov concentration. B-3 rub ua ntej nyob rau hauv boiling acid, nyob rau hauv welded tsim, thiab nyob rau hauv acid nqa kab ferric ions.

Hastelloy B-3 feem ntau nkag mus rau qhov kev pabcuam hauv qhov zoo li-welded. B-2 feem ntau yuav tsum tau muaj kev daws teeb meem tag nrho nyob ze 1,066 degrees Celsius ua raws li cov dej quench.

Tsis yog alloy tolerates oxidizers. Ferric lossis cupric ions, nitric acid, chlorine ntub thiab hypochlorite yuav tsum tau Hastelloy C-276 lossis C-22 hloov.

B-3 feem ntau raug nqi 10-25% ntxiv rau ib kilogram, tab sis tshem tawm qhov yuav tsum tau kho tom qab vuam cua sov feem ntau ua rau cov khoom tiav pheej yig dua los tsim.

Hastelloy B-2 vs B-3: tshuaj muaj pes tsawg leeg piv

Cov lus 1. Cov kev txwv tsis pub muaj ib qho ASTM B333 / B335 cov khoom tshwj xeeb (cov ntawv tshaj tawm zeb txwv).

Cov npe sib npaug: Hastelloy B-2=UNS N10665, W.Nr. 2.4617, EN NiMo28, GB NS322. Hastelloy B-3=UNS N10675, W.Nr. 2.4600, EN NiMo29Cr, JIS NW 6750, GB NS3203.

Hastelloy B-2 vs B-3: engineering zog piv

Table 2. Chav-kub minima ib ASTM B333 phaj specification; Kev ntsuam xyuas corrosion yog qhov kev pom zoo engineering.

Dab tsi yog qhov txawv ntawm Hastelloy B-2 thiab Hastelloy B-3?

B-3 tsis yog qhov sib txawv corrosion. Nws yogB2 hlaunrog cov metallurgy rebalanced ces cov alloy ciaj sia nws tus kheej fabrication. Tib nickel-molybdenum chemistry, qhov tseem ceeb yog tib yam hydrochloric acid tsis kam, thiab cov lus teb sib txawv kiag li rau lub qhov rais kub ntawm 500-900 degrees Celsius.

Tsev neeg B yog peb tiam- zaj dab neeg, thiab txhua tiam tau kho qhov ua tsis tiav ntawm ib qho ua ntej nws. Tus thawj Hastelloy B (UNS N10001, 1920s) muaj 4-6% hlau thiab 1% silicon thiab tsis tuaj yeem siv raws li-welded mob, vim tias qhov vuam kub- cuam tshuam thaj tsam precipitated grain-border carbides thiab poob nws corrosion kuj. B-2 (1960s) daws tau tias los ntawm slashing carbon mus rau 0.02%, silicon rau 0.10% thiab hlau mus rau 2% siab tshaj plaws. Nws ua haujlwm, thiab B-2 tau los ua cov khoom siv classic rau hydrochloric acid txhua.

Tab sis B-2 nqa qhov teeb meem thib ob, qeeb qeeb: vim nws cov matrix hnyav heev nrog molybdenum, nws yog metastable. Muab ob peb feeb nyob rau hauv nruab nrab qhov kub thiab txias nws rearranges mus rau hauv kev txiav txim intermetallic tebchaw. B-3 (1990s) tau tsim tshwj xeeb los tua cov txheej txheem, siv chromium thiab hlau raws li kev sib koom ua ke ntxiv es tsis yog impurities kom txo qis. Nyeem cov lus muaj pes tsawg leeg dua nrog qhov ntawd hauv siab thiab cov qauv tsim ua kom pom tseeb: molybdenum nyob siab, cov pa roj carbon qis dua, thiab chromium thiab hlau tau nce mus rau lub hom phiaj.

Vim li cas Hastelloy B-2 poob ductility ntawm 550 thiab 900 degrees Celsius?

Vim tias cov nickel matrix tuav ntau molybdenum ntawm 1,150 degrees Celsius dua li nws tuaj yeem tuav ntawm 750 degrees Celsius. Qhov ntau dhau los ntawm kev daws raws li xaj Ni4Mo, hu ua beta theem. Nws tsim raws li nyuaj, nkig platelets uas nucleate ntawm grain ciam teb thiab dislocations, thiab ob peb feeb nyob ze 750 degrees Celsius yog txaus los pib txheej txheem.

Ib qho piv txwv yooj yim pab. Molybdenum hauv nickel coj zoo li qab zib yaj hauv cov tshuaj yej kub. Thaum tov -annealing kub, npib tsib xee tuav tag nrho nws yooj yim. Txias cov hlau rau hauv 500-900 degrees Celsius band thiab npib tsib xee tsis tuaj yeem tuav ntau molybdenum, yog li cov nyiaj seem cais tawm raws li cov muaju, txoj kev qab zib crystallises hauv qab ntawm lub thawv txias. Hauv B-2 cov crystals yog Ni4Mo.

Qhov kev tshwm sim ntawm metallurgical ib leeg ua rau ob qhov kev ua tsis tiav, uas yog vim li cas B-2 teeb meem feem ntau tsis raug kuaj pom:

1. Tshuab tsis ua hauj lwm. Ni4Mo platelets nyuaj thiab nkig. Lawv rhuav tshem chav - qhov kub thiab txias elongation thiab cuam tshuam lub zog, yog li cov khoom siv B-2 sensitized tuaj yeem tawg thaum tsim, thaum hydrotest, los yog thaum lub sij hawm thermal hloov hauv kev pabcuam.
2. Corrosion tsis ua hauj lwm. Cov precipitate yog molybdenum- nplua nuj, yog li cov matrix tam sim ntawd nyob ib ncig ntawm nws yog molybdenum- depleted. Nyob rau hauv hydrochloric acid cov depleted bands corrode preferentially. Nyob rau hauv ib tug welded sib koom ua ke no tshwm sim li riam-kab nres, ib tug nqaim, tob groove khiav ib sab ntawm fusion kab nyob rau hauv lub tshav kub- cuam tshuam cheeb tsam.
3. Qhov txiaj ntsig zoo yog tias qhov cua txias ntawm qhov rais no tseem ceeb npaum li qhov kub siab tshaj plaws. Ib daim ntawv nyias B-2 daim ntawv quenched sai heev los ntawm cov qhab tuaj yeem los ntawm kev huv. Ib lub phaj tuab B-2 phaj uas txias maj mam, ib qho kev sib txuas sib txuas uas ua rau thaj chaw muaj kev cuam tshuam los ntawm tshav kub nyob rau hauv lub band ntau zaus, los yog lub voj voog kev ntxhov siab uas tuav ntawm 650 degrees Celsius rau ntau teev yuav tsis. Qhov no yog vim li cas tus qauv kev taw qhia rau B-2 yog qhov tseeb: kev daws teeb meem ntawm 1,066 degrees Celsius, quench sai, thiab tsis txhob tso cov hlau nyob rau hauv kev pab ntev ntawm roughly 538 thiab 816 degrees Celsius.

Hastelloy B-3 tiv thaiv Ni4Mo nag lossis daus li cas?

B-3 tawm tsam qhov teeb meem ntawm plaub pem hauv ntej ib zaug. Nws tsa lub qhov rais molybdenum, ntxiv 1-3% chromium thiab 1-3% hlau los hloov txoj kev xaj, tee carbon rau 0.01% siab tshaj plaws nrog titanium muaj los khi cov seem, thiab tuav cov sulfur tsawg heev rau kub ductility. Lub nrawm-forming Ni4Mo beta theem yog hloov loj los ntawm qeeb-forming Ni3Mo theem.

Chromium 1.0-3.0% stabilizes lub ntsej muag -centred cubic matrix thiab slows lub short-range ordering nickel thiab molybdenum atoms uas noob Ni4Mo. Kev txiav txim yog thawj kauj ruam ntawm nag lossis daus, yog li qeeb nws ncua txhua yam hauv qab dej.

Hlau 1.0-3.0% hloov cov thermodynamics ntawm kev sib tw precipitates. Nyob rau hauv B-3 tshuav nyiaj li cas, Ni3Mo dhau los ua qhov kev txiav txim siab tshaj plaws es tsis txhob Ni4Mo, thiab Ni3Mo loj hlob qeeb dua.

Carbon 0.01% siab tshaj, ntxiv rau titanium txog 0.20%, tshem tawm cov carbide shortcut. Hauv B-2, nplej- ciam teb carbides ua raws li npaj txhij-ua nucleation chaw; nrog yuav luag tsis muaj carbon dawb los tsim lawv, nag lossis daus yuav tsum pib los ntawm khawb hauv cov nplej sab hauv, uas yuav siv sijhawm ntev dua.

Molybdenum 27.0-32.0% khaws hydrochloric acid tsis kam. Qhov no yog lub ntsiab lus uas neeg feem ntau nco: B-3 tsis tau yuav thermal stability los ntawm kev txi molybdenum. Nws yuav kev ruaj ntseg los ntawm kev sib npaug ntawm cov khoom me me nyob ib puag ncig lub siab-molybdenum core.

Manganese mus txog 3.0% thiab txhuas mus txog 0.50% txhim kho kev ua haujlwm kub thiab deoxidation, yog li B-3 tuaj yeem ua kub-tsim thiab dov yam tsis muaj lub kua muag uas plagued ua ntej B alloys.

Sulfur kuj tsim nyog sau cia. B-3 caps nws ntawm 0.01% tiv thaiv 0.03% rau B-2. Sulfur thiab lwm cov ntsiab lus qis-melting-cov ntsiab lus sib cais rau cov ciam teb thiab ua rau kub tawg thaum lub sij hawm vuam thiab kub ua hauj lwm, yog li no zawm yog ib tug fabrication margin, tsis yog ib tug corrosion.

Qhov kev sib piv ntawm nag lossis daus kinetics qhia tau li cas?

Nyob rau lub sijhawm -kub- hloov pauv, B-2 pib nag lossis daus Ni4Mo hauv feeb hauv 700-870 degrees Celsius, nrog qhov ceev tshaj plaws kinetics ze 750 degrees Celsius. B-3 xav tau ob peb teev ntawm qhov raug nyob ze 650 degrees Celsius ua ntej qhov kev tshem tawm thib ob tshwm sim. Qhov ntawd yog ib qho kev hloov ntawm kwv yees li ib mus rau ob qhov kev txiav txim loj hauv lub sijhawm, thiab nws yog vim li cas B-3 tuaj yeem siv tau raws li-welded.

Los nag ua raws C- nkhaus. Thaum kub kub muaj me ntsis thermodynamic tsav tsheb; ntawm qhov kub thiab txias atoms diffuse qeeb heev. Ib qho chaw hauv nruab nrab zaum ntawm qhov ntswg ntawm qhov nkhaus, qhov twg nag lossis daus ceev tshaj plaws. Rau B-2 lub qhov ntswg zaum nyob rau sab saum toj ntawm qhov kub thiab txias ib cheeb tsam uas cuam tshuam los ntawm tshav kub dhau mus. B-3 thawb lub qhov ntswg mus ntev ntev. Cov lus hauv qab no txhais qhov ntawd mus rau hauv kev muaj tiag.

Table 3. Fabrication-Txoj kev txhais ntawm B-2 piv rau B-3 lub sij hawm-kub-hloov tus cwj pwm.

Dab tsi alloy resists hydrochloric acid zoo dua, B-2 lossis B-3?

Hauv cov tshuaj -annealed mob, nyob rau hauv ntshiab hydrochloric acid, lawv yog sib npaug. Ob qho tib si feem ntau khiav qis dua 0.1 hli / xyoo los ntawm chav tsev kub txog li 70 degrees Celsius ntawm txhua qhov concentration, thiab qis dua 0.5 hli / xyoo nyob rau hauv feem ntau kub kub. B-3 yeej sai li sai tau thaum welds, kub dua los yog impurities nkag mus rau hauv daim duab.

Hydrochloric acid defeats yuav luag txhua hom engineering hlau. Nws rhuav tshem cov hlau tsis muaj steel, nws tawm tsam feem ntau cov npib tsib xee -chromium alloys, thiab nws yuav corrode titanium. The nickel-molybdenum system survives because molybdenum forms a stable, dense passive film in a reducing (oxygen-free) acid. Ib qho chromium-raws li cov yeeb yaj kiab passive, uas yog qhov ua rau cov hlau tsis muaj steel ua haujlwm, tsuas yog tsis tuaj yeem khaws cia hauv ib puag ncig ntawd, vim tias tsis muaj oxidising hom tuaj yeem kho nws.

Txij li thaum ob qho tib si alloys muaj kwv yees li 28% molybdenum, ob qho tib si tsim tib zaj duab xis tiv thaiv, thiab ob qho tib si muab cov txiaj ntsig zoo ib yam. Cov lus hauv qab no muab cov hnab ntawv siv tau los ntawm ob qib hauv cov kua qaub ntshiab.

Table 4. Tus sawv cev hydrochloric acid kev ua tau zoo rau kev daws -annealed B-2 thiab B-3 hauv cov kua qaub ntshiab, deaerated.

B-2 thiab B-3 sib txawv li cas thaum hydrochloric acid nqa ferric paug?

B-3 zam nws zoo dua, tab sis tsis muaj cov hlau yuav tsum tau teev tseg rau hydrochloric acid uas muaj oxidising ions. Thaum ferric, cupric lossis dissolved-oxygen paug yog ib feem ntawm cov txheej txheem kwj, txav mus rau Hastelloy C-276 lossis Hastelloy C-22.

Ferric ions yog cathodic depolariser. Lawv txais cov electrons ntawm cov hlau saum npoo thiab yog li ua kom cov molybdenum puas tsuaj -nplua nuj passive zaj duab xis sai dua li cov kua qaub tuaj yeem rov tsim dua. Cov nyhuv yog qhov txaus ntshai: tsawg li 50 ppm ntawm ferric hlau tuaj yeem thawb tus nqi qis dua 0.1 hli / xyoo mus rau siab dua 10 hli / xyoo rau ob qib. B-3 ua tau zoo dua B-2 rau ob qho laj thawj. Nws 1-3% chromium muab cov zaj duab xis saum npoo zoo dua me ntsis rov qab los, thiab, qhov tseem ceeb, nws tsis muaj embrittled, molybdenum-depleted tshav kub-cuam tshuam cheeb tsam rau kev tawm tsam kom mloog zoo.

Table 5. Cov ntaub ntawv sawv cev ntawm chav kuaj sib txawv. Cov nqi tsuas yog qhia tau; ib txwm txheeb xyuas nrog daim coupon hauv koj tus kheej cov txheej txheem kwj.

Hauv cov nroj tsuag tiag tiag, ferric qib siab tshaj 500 ppm yog qhov tshwm sim, vim tias hydrochloric acid tau yooj yim khaws cov hlau los ntawm carbon steel piping, twj thiab cia. Tshwj tsis yog tias koj tuaj yeem lav ultra- kua qaub ntshiab thiab saib xyuas nws tsis tu ncua, B-3 yog qhov kev nyab xeeb dua. Thiab yog tias oxidising paug tsis tuaj yeem zam tau, tsis yog qib B yog cov lus teb yog: siv C-276.

Puas yog Hastelloy B-3 xav tau kev kho cua sov tom qab vuam?

Tsis yog, tsis yog rau cov kev pabcuam ntshiab hydrochloric acid, thiab qhov no yog ib qho kev tsim khoom loj tshaj plaws ntawm B-3. B-2, los ntawm qhov sib piv, feem ntau yuav tsum muaj kev daws teeb meem tag nrho nyob ze 1,050-1,100 degrees Celsius ua raws li dej quench.

Tshaj tawm -weld kev kho cua sov ntawm lub nkoj loj yog kim thiab pheej hmoo. Nws xav tau lub cub tawg loj txaus rau tag nrho cov fabrication, nws qhia distortion uas yuav tsum tau re-rounding thiab re-machining ntawm flanges, nws yuav tsum tau cov khoom yuav tsum tau thauj ob zaug, thiab ib tug qeeb los yog tsis txaus quench yuav ua rau cov tivthaiv phem dua ua ntej. Txhua tus ntawm cov kauj ruam no yog lub sijhawm thiab kev pheej hmoo zoo. B-3 tshem tawm cov kauj ruam.

B-3 tseem yog cov tshuaj annealed hauv cov xwm txheej tshwj xeeb:

• Kev pabcuam hydrofluoric acid, lossis sib xyaw HCl + HF ntws, qhov uas ib txwm pom zoo siv tshuaj anneal.
• Boiling concentrated HCl nyob rau hauv siab - qhov tshwm sim siab ciam teb, qhov twg tus tswv xav tau qhov siab tshaj plaws.
• Kev ua haujlwm txias txias: B-3 ua haujlwm-hardens sai, yog li txias txias saum toj li 10-15% feem ntau hu rau qhov nruab nrab lossis qhov kawg daws anneal los kho cov ductility.
• Code, tus neeg siv khoom tshwj xeeb lossis cov txheej txheem tsim muaj ntawv tso cai uas tso cai rau nws.
• Kho welds ntawm cov ntu tuab qhov uas tswj siab siab thiab tus neeg tsim khoom xav kom txo qis kev ntxhov siab.

Yuav siv cov khoom siv vuam thiab cov txheej txheem dabtsi rau B-2 thiab B-3?

Weld B-2 nrog ERNiMo-7; Weld B-3 nrog ERNiMo-10 (DIN 2.4695 liab qab hlau, DIN 2.4696 coated electrodes). Rau ob qib siv cov cua kub qis, ua kom qhov kub ntawm qhov sib txawv hauv qab 100-120 degrees Celsius, thiab tsis txhob preheat tshaj qhov xav tau los tsav cov dej noo.

Filler thiab txheej txheem ob qho tib si tseem ceeb, vim tias lub hauv paus hlau zoo tuaj yeem raug puas tsuaj los ntawm qhov tsis zoo.

Table 6. Cov ntsiab lus ntawm kev xyaum vuam. Ib txwm tsim nyog WPS / PQR tiv thaiv qhov sib koom ua ke thiab tuab.

Ib txoj cai tiv thaiv kab mob tsim nyog tau txais kev pom zoo: tsis txhob zom B- qib alloy nrog lub log uas tau kov cov pa roj carbon steel, thiab tsis txhob kov nws nrog carbon steel slings lossis chains. Embedded hlau hais xeb nyob rau hauv kev pab cuam thiab pib pits uas tuaj yeem perforate phab ntsa xav tsis thoob sai sai.

Puas yog Hastelloy B-2 thiab B-3 hloov pauv tau hauv cov khoom siv hydrochloric acid uas twb muaj lawm?

Lub cev muaj, txheej txheem tsis muaj. Hloov B-3 rau B-2 yog yuav luag ib txwm lees txais thiab feem ntau tau txais txiaj ntsig. Hloov B-2 rau B-3 tsis yog, tshwj tsis yog tias koj rov tsim nyog cov txheej txheem vuam thiab rov ua haujlwm tom qab vuam cua sov.

Ua haujlwm los ntawm daim ntawv teev npe hauv qab no ua ntej yuav hloov pauv.

Tsim code. Paub meej tias qhov kev ntxhov siab tso cai rau UNS tus lej tshwj xeeb ntawm koj qhov ntsuas kub ntawm qhov tam sim no ASME Tshooj II, Ntu D. Qhov tseem ceeb rau N10665 thiab N10675 tsis zoo ib yam, yog li tsis txhob xav tias qhov sib pauv ncaj ntawm qhov kub siab.

Vuam txheej txheem. Kev hloov pauv ntawm cov hlau los yog cov hlau muab tub lim yog qhov tseem ceeb ntawm qhov hloov pauv. Re- tsim nyog rau WPS thiab PQR, thiab nco ntsoov tias vuam B-3 puag nrog ERNiMo-7 muab tub lim ua rau kev tso nyiaj nrog B-2-zoo li ruaj khov, uas ua rau lub hom phiaj.

Kev kho cua sov. Yog hais tias cov khoom B-2 uas twb muaj lawm tau muab annealed thiab quenched, paub meej tias B-3 hloov tau muab tib txoj kev.

Cov ntaub ntawv. Yuav tsum tau daim ntawv pov thawj zeb xeem rau EN 10204 3.1 (3.2 rau kev pabcuam tseem ceeb) thiab 100% cov ntaub ntawv pov thawj zoo ntawm txhua qhov cua sov.

Galvanic cais. B-qib alloys yog cathodic rau carbon steel thiab txhuas. cais cov kev txhawb nqa, flanges thiab fasteners nrog tsis yog -paskets, lub tes tsho thiab ntxhua khaub ncaws.

Txheej txheem chemistry. Yog tias cov kwj deg tau hloov pauv txij li thawj qhov tshwj xeeb, rov- tshawb xyuas cov lus nug oxidising-ion ua ntej koj rov- xaj dab tsi.

Thaum twg Hastelloy B-2 tseem ua rau muaj kev nkag siab?

Hauv peb qhov xwm txheej: kev kho qub qub thiab hloov pauv, huv si tsis yog -welded lub luag haujlwm ntawm qhov kub nruab nrab, thiab cov haujlwm uas tswj hwm kev cai tswj hwm B-2. Sab nraum cov rooj plaub no, B-3 yog qhov yuav zoo dua.

B-2 yog cov hlau zoo tiag tiag. Nws tsuas muaj lub qhov rais nqaim, thiab lub qhov rais ntawd yooj yim rau kev hwm hauv cov ntawv thov no:

• Hloov sab hauv rau ib kab B-2 uas twb muaj lawm, tais, lossis tus xa khoom, qhov sib xyaw ua ke yuav tsim cov ntaub ntawv thiab mob taub hau galvanic.
• Machined Cheebtsam uas tsis pom lub voj voog thermal: valve stems, twj tso kua mis shafts, orifice daim hlau, pas ntsuas kub qhov dej, me me fittings.
• Nyias- ntsuas cov ntaub ntawv hauv ob sab phlu thiab cov pob qij txha nthuav dav uas tuaj yeem ua tiav cov kev daws teeb meem -annealed thiab dej-quenched tom qab tsim, nyob rau hauv ib lub khw nruab rau nws.
• Cov phiaj xwm tswj hwm los ntawm cov txheej txheem tsim muaj ntawv tso cai, tus tswv tus qauv, lossis cov cuab yeej cuab tam tam sim no uas muaj npe B-2 meej.
• Huv si, qis-kub, tsis yog-welded txo-kev pabcuam acid qhov twg tus nqi ntxiv ntawm B-3 yuav tsis muaj dab tsi.

Tus nqi sib piv zoo li cas dhau ntawm cov khoom siv lub neej?

B-3 nqi li ntawm 10-25% ntxiv rau ib kilogram. Rau cov khoom siv welded, tag nrho cov nqi nruab nrab feem ntau nyiam B-3, vim tias nws tshem tawm cov tshuaj tom qab vuam anneal thiab cov kev pheej hmoo rov ua haujlwm nrog nws.

Cov khoom siv tus nqi tsuas yog ib kab ntawm daim ntawv them nqi. Cov lus hauv qab no qhia qhov twg cov nyiaj txav mus tiag tiag.

Rooj 7. Tus nqi tsav tsheb. Cov feem pua ​​​​yog cov kev soj ntsuam kev lag luam thiab yuav tsum tau lees paub tawm tsam tam sim no zeb thiab fabricator hais.

Muaj qhov thib ob, nyuaj dua -kom- ntsuas qhov txuag: kev xaiv. Lub nkoj B-3 tuaj yeem kho hauv thaj teb nrog lub vuam thiab rov qab mus rau kev pabcuam. Lub nkoj B-2 uas xav tau ib qho vuam feem ntau xav tau kev kho cua sov uas cov nroj tsuag hloov tsis tuaj yeem haum.

Tshaj li hydrochloric acid: B-2 thiab B-3 piv li cas hauv lwm cov xov xwm?

Nyob rau hauv cov ntshiab txo acids ob yog nyob ze, thiab B-3 yog lub neej ntawd kev nyab xeeb nyob rau hauv txhua rooj plaub. Hauv oxidising media ob qho tib si tsis ua haujlwm, thiab Hastelloy C-276 lossis C-22 yuav tsum tau ua.

Nruab nrab ntawm nruab nrab:

Sulfuric acid (ntshiab, tsis yog -oxidising)

Ob lub alloys tiv taus cov ntshiab sulfuric acid zoo nyob rau nruab nrab concentration thiab kub; Hauv boiling 10% acid, tus nqi nyob qis dua 0.1 mm / xyoo. B-3 tuav cov impurities zoo dua. Tshaj li ntawm kwv yees li 60% concentration, los yog nrog ib hom oxidising tam sim no, txav mus rau C-276.

Phosphoric acid

Ob leeg tiv taus cov ntshiab phosphoric acid. Rau cov ntub dej - txheej txheem phosphoric acid nqa cov fluorides thiab chlorides, B-3's siab molybdenum muab nws ib tug ntug nyob rau hauv lub aggression theem, tab sis C-276 thiab C-22 tseem yog ib txwm specification rau oxidising txheej txheem kwj.

Acetic, formic thiab lwm yam organic acids

Ob leeg zoo heev nyob rau hauv kev txo qis. B-3 zoo dua rau cov welded reactors nyob rau hauv acetic acid, acetic anhydride, methyl methacrylate thiab ethylene glycol ntau lawm, precisely vim hais tias cov hlab ntsha yog welded thiab B-3 tolerates lub weld voj voog.

Hydrobromic acid

Ob leeg zoo heev; B-3 yog teev thaum cov khoom siv welded. Qhov no yog ib daim ntawv thov tab sis tsis sib tham, vim HBr coj zoo li HCl thiab tshem tawm yuav luag txhua lwm yam hlau.

Hydrofluoric acid thiab sib xyaw HCl + HF

B-3 tuaj yeem siv tau, tab sis ib txwm siv cov tshuaj anneal ib txwm pom zoo ua ntej kev pabcuam. Ntau tus neeg tsim qauv nyiam C-276 lossis Monel rau cov fluoride-cov kabmob kwj dej, yog li txheeb xyuas koj cov tshuaj fluoride thiab qhov kub thiab txias.

Oxidising media: nitric acid, chromic acid, hypochlorite, ntub chlorine, ferric lossis cupric chloride

Tsis yog alloy. Cov molybdenum-nplua nuj zaj duab xis uas ua haujlwm tau zoo hauv kev txo cov kua qaub yog rhuav tshem los ntawm oxidisers. Qhia meej Hastelloy C-276 rau kev sib xyaw thiab ua haujlwm oxidising nruab nrab, lossis Hastelloy C-22 rau cov oxidising zoo.

Table 8. Media xaiv matrix rau tsev neeg B thiab nws li ib txwm hloov.

Dab tsi yog qhov kev pabcuam nyuaj ntawm ob qho tib si alloys

Tsis muaj oxidisers, thiab tsis ntev - kev pab cuam nyob rau hauv 550-900 degrees Celsius nag lossis daus qhov rais. Nyob rau hauv huab cua, txog 540 degrees Celsius yog lub qab nthab rau ob qho tib si qib; hauv kev txo cov pa roj los yog lub tshuab nqus tsev, qhov ntsuas kub ntau dua yog tso cai.

Cov kev txwv uas ua rau kev ua tsis tiav tiag tiag yog cov no:

1. Oxidizing ions. Kwv yees li 50 ppm ntawm ferric lossis cupric ion tuaj yeem nce hydrochloric acid corrosion tus nqi los ntawm ob qhov kev txiav txim ntawm qhov loj. Khaws cov hlau thiab tooj liab tawm ntawm qhov system: tsis muaj carbon steel lossis tooj liab kav dej ntws, tsis muaj xeb, tsis muaj tooj liab gaskets.
2. Nruab nrab-kev pabcuam kub. Tsis txhob tuav ob qho tib si ntawm qhov kub ntawm 550 thiab 900 degrees Celsius nyob rau hauv load. B-2 tshwj xeeb yog txwv los ntawm kev pabcuam ntev nyob ib puag ncig 538-816 degrees Celsius.
3. Atmospheric kub qab nthab. Hauv cov huab cua oxidising xws li huab cua, npaj rau lub qab nthab ze 540 degrees Celsius. Hauv lub tshuab nqus tsev lossis txo cov cua, B-3 tau siv zoo tshaj qhov ntawd, yog vim li cas nws tshwm nyob rau hauv lub tshuab nqus tsev vacuum hardware.
4. Kub- ua haujlwm paug. Cua sov rau forging los yog kub forming yuav tsum tsis txhob sib cuag nrog sulfur, phosphorus, lead thiab lwm yam tsawg -melting- taw tes hlau, siv tsawg- sulfur roj thiab ib tug huv si, me ntsis txo cov cua sov. Cov nplaim taws yuav tsum tsis txhob cuam tshuam ncaj qha rau ntawm qhov chaw ua haujlwm.
5. Galvanic coupling. Qib B yog qhov muaj txiaj ntsig zoo rau carbon steel thiab aluminium. Cais lawv cov hluav taws xob, los yog cov hlau pheej yig dua los ua cov anode sacrificial.
6. Chloride stress corrosion cracking. Ob lub alloys muaj kev tiv thaiv zoo rau cov tshuaj chloride-induced SCC vim lawv cov ntsiab lus siab nickel, uas yog ib qho ntawm lawv qhov tsis zoo ntawm stainless hlau.

Yuav ua li cas engineers qhia Hastelloy B-3 hauv 2026?

Qhia cov alloy los ntawm UNS tus lej, cov khoom tsim los ntawm ASTM tus lej, kev kho cua sov, thiab cov ntaub ntawv koj xav tau. Tsis txhob xaj ntawm lub npe lag luam ib leeg.

Kev ua tiav B-3 yuav khoom specification muaj cov hauv qab no:

• Khoom siv: UNS N10675, W.Nr. 2.4600, GB NS3203. Hla -kos tag nrho peb ntawm daim ntawv pov thawj zeb.
• Khoom specification los ntawm daim ntawv: ASTM B333 / ASME SB333 rau phaj, ntawv thiab sawb; ASTM B335 / ASME SB335 rau bar; ASTM B622 / ASME SB622 rau seamless yeeb nkab thiab raj; ASTM B619 thiab B626 / ASME SB619 thiab SB626 rau welded yeeb nkab thiab raj; ASTM B366 / ASME SB366 rau fittings; ASTM B564 / ASME SB564 rau forgings.
• Cov xwm txheej: cov tshuaj annealed ntawm 1,050-1,100 degrees Celsius, dej quenched.
• Mechanical txais: tensile 760 MPa yam tsawg kawg nkaus, tawm los 350 MPa yam tsawg kawg nkaus, elongation 40% yam tsawg kawg nkaus.
• Cov ntaub ntawv: zeb xeem daim ntawv pov thawj rau EN 10204 3.1, los yog 3.2 rau siab- khaws cov kev pabcuam tseem ceeb; tag nrho tshav kub traceability.
• Kev pov thawj: 100% kev txheeb xyuas cov khoom zoo los ntawm XRF lossis OES ntawm txhua qhov cua sov thiab txhua daim, ua tiav ntawm daim ntawv txais nyiaj, tsis yog ntawm lub zeb.
• Kev pabcuam qaub: xeev NACE MR0175 / ISO 15156 ua raws yog hydrogen sulfide nyob txhua qhov chaw hauv lub cev.
• Vuam: WPS thiab PQR tsim nyog nrog ERNiMo-10 muab tub lim, interpass hauv qab 100 degrees Celsius, tsis muaj preheat.
• NDE: radiographic lossis automated ultrasonic kuaj ntawm lub siab- khaws cov welds, dye penetrant ntawm cov hauv paus hla, nozzle txuas welds thiab txhua qhov chaw uas tau muab tshem tawm ib ntus.
• Kev huv huv: cov hlau tshwj xeeb- cov cuab yeej pub dawb, sib tsoo lub log thiab cia; tsis muaj kev sib cuag nrog carbon steel tuav iav.
• Cov txheej txheem pov thawj: yog tias cov kua qaub tsis huv, khiav ASTM G31 daim ntawv pov thawj rau kev sim hauv cov txheej txheem tiag tiag ua ntej cov khoom siv zaum kawg tso tawm.

Kuv yuav tsum xaiv lub alloy twg? Ib txoj kev rau - kauj ruam xaiv

Teb tsib nqe lus nug txog cov kwj deg thiab ib qho txog kev tsim khoom, thiab kev xaiv feem ntau yog qhov tseeb.

1. Cov kwj dej puas muaj oxidising hom (Fe3+, Cu2+, yaj oxygen, nitric acid, chlorine ntub dej)? Yog tias muaj, nres. Siv Hastelloy C-276 lossis C-22, tsis yog B alloy.
2. Puas yog cov khoom siv welded, lossis puas yuav puas tau welded hauv thaj teb? Yog tias muaj, xaiv B-3.
3. Puas yog cov kua qaub ua kom npau npau, lossis nws puas muaj zog (siab dua ~ 20%)? Yog tias muaj, xaiv B-3.
4. Puas muaj kev pheej hmoo ntawm kev kis kab mob hlau los ntawm cov pa roj carbon steel? Yog tias muaj, xaiv B-3, thiab kho cov kav dej ntws.
5. Puas yog lub luag haujlwm huv, txias, tsis yog -welded, thiab twb tau teev tseg raws li B-2? B-2 tau txais thiab pheej yig dua.
6. Qhov twg koj xaiv, thov MTR thiab khiav PMI. Qib sib xyaw- nce ntawm B-2 thiab B-3 yog ib qho teeb meem kev lag luam uas tau sau tseg, vim tias ob qho tib si zoo ib yam thiab tus nqi sib txawv.

Cov lus nug uas nquag nug

1. Puas yog Hastelloy B-3 zoo dua Hastelloy B-2?

Yog, rau yuav luag txhua qhov kev tsim kho tshiab. B-3 qhov sib tw B-2's hydrochloric acid tsis kam nyob rau hauv cov mob annealed thiab ntxiv cov thermal stability, yooj yim fabrication, thiab muaj peev xwm nkag mus rau kev pab raws li -welded. B-2 tseem yog qhov kev xaiv muaj txiaj ntsig zoo rau kev huv, txias, tsis yog-welded kev pab cuam txo cov kua qaub thiab rau kev hloov pauv zoo li qub.

2. Vim li cas Hastelloy B-2 ua nkig tom qab vuam?

Vuam tsav lub tshav kub- thaj tsam cuam tshuam txog 550-900 degrees Celsius, qhov twg B-2 sai sai precipitates lub intermetallic compound Ni4Mo (beta theem). Lub precipitate yog tawv thiab nkig thiab tawm molybdenum-depleted bands nyob ib ncig ntawm nws, ua rau ob qho tib si ductility poob thiab riam-kab corrosion nres. Tom qab-weld tov anneal ntawm txog 1,066 degrees Celsius nrog dej quench dissolves precipitate thiab restores zog.

3. Puas yog Hastelloy B-3 xav tau kev kho cua sov tom qab vuam?

Tsis yog rau kev pabcuam ntshiab hydrochloric acid. B-3 yog tsim tshwj xeeb rau raws li -welded siv. Ib qho tshuaj anneal ntawm 1,050-1,100 degrees Celsius tseem yuav raug teev tseg rau hydrochloric-hydrofluoric tov acid cov kev pabcuam, rau cov khoom ua haujlwm txias, lossis qhov twg tus lej lossis cov neeg siv khoom tshwj xeeb xav tau nws.

4. Hastelloy B-2 precipitate Ni4Mo kub npaum li cas?

Nruab nrab ntawm kwv yees li 550 thiab 900 degrees Celsius, nrog rau nag xob nag cua ceev tshaj ze 750 degrees Celsius. Qhov raug ntsuas nyob rau hauv feeb, tsis yog teev, uas yog vim li cas lub weld thermal voj voog yog txaus los pib nws. B-2 yuav tsum tsis txhob siv nyob rau hauv kev pab cuam ntev li ntawm 538 thiab 816 degrees Celsius.

5. Hastelloy B-3 puas tuaj yeem hloov B-2 hauv lub nkoj uas twb muaj lawm?

Feem ntau yog, thiab feem ntau nws yog ib qho kev hloov kho tshiab. Ua ntej hloov pauv, lees paub ASME Tshooj II Tshooj D tso cai rau kev ntxhov siab rau N10675 ntawm koj qhov ntsuas kub tsim, rov- tsim nyog WPS thiab PQR nrog ERNiMo-10 muab tub lim, thiab paub meej tias qhov hloov pauv tau muab rau hauv cov tshuaj tov-annealed thiab quenched mob nrog daim ntawv pov thawj tag nrho.

6. Dab tsi muab cov hlau siv rau Hastelloy B-2 thiab B-3?

B-2 yog welded nrog ERNiMo-7 (W.Nr. 2.4615) lossis ENiMo-7 electrodes. B-3 yog welded nrog ERNiMo-10, nrog rau B-3 hlau tsim DIN 2.4695 thiab npog electrodes DIN 2.4696. Tsis txhob siv ERNiMo-7 tso nyiaj ntawm B-3 lub hauv paus hlau yog tias kev txhim kho thermal stability ntawm kev sib koom ua ke teeb meem.

7. Puas yog Hastelloy B-2 lossis B-3 sib nqus?

Tsis yog. Ob leeg yog tag nrho austenitic nickel-molybdenum alloys nrog lub ntsej muag -centred cubic crystal qauv thiab tsis yog-magnetic nyob rau hauv cov tshuaj-annealed mob.

8. Qhov twg kim dua, Hastelloy B-2 lossis B-3?

B-3 tus nqi kwv yees li 10-25% ntxiv rau ib kilogram. Txawm li cas los xij, vim tias B-2 feem ntau xav tau cov tshuaj tom qab-weld anneal, tag nrho cov nqi ntawm cov khoom siv welded B-2 feem ntau yog 25-30% siab dua, yog li B-3 nquag yeej ntawm cov nqi tsim.

9. Suav GB sib npaug ntawm Hastelloy B-3 yog dab tsi?

Raws li GB / T 15007, Hastelloy B-3 sib raug rau NS3203 thiab Hastelloy B-2 sib raug rau NS322. Ib txwm txheeb xyuas qhov kev xaiv tawm tsam daim ntawv pov thawj zeb tam sim no, vim tias cov npe khoom muag qee zaus nqa cov lej tsis raug.

10. Puas yog Hastelloy B-2 raug txiav tawm?

Tsis raug cai, tab sis nws tsis yog lub neej ntawd lawm. Tshiab welded designs yuav tsum default rau B-3. B-2 tseem muaj dav thiab nyob rau hauv kev pabcuam dav dav rau kev saib xyuas qub txeeg qub teg, kho thiab kev siv cov ntaub ntawv uas tus thawj specification npe nws.

11. Hastelloy B-3 piv rau zirconium rau kub hydrochloric acid: uas yeej?

Zirconium outperforms ob qib B nyob rau hauv ntshiab, kub hydrochloric acid, tab sis nws yog deb tshaj rhiab heev rau ferric thiab fluoride paug thiab raug nqi ntau ntau. Qhov twg kwj purity tsis tuaj yeem lav tau, B-3 yog qhov kev xaiv zoo dua thiab kev lag luam ntau dua.

12. B-2 lossis B-3 puas tuaj yeem ua cov tshuaj hydrochloric acid uas muaj ferric ions?

Tsuas yog me me xwb, thiab B-3 tuav lawv zoo dua. Tsawg li 50 ppm ntawm ferric ion tuaj yeem nce tus nqi corrosion siab tshaj 10 hli / xyoo rau ob qib. Ntawm 500 ppm nyob rau hauv 10% acid ntawm 60 degrees Celsius, kev ntsuam xyuas qhia tau hais tias txog 2.1 hli / xyoo rau B-2 tawm tsam li 0.4 hli / xyoo rau B-3. Saum toj no cov theem, qhia Hastelloy C-276.

13. Qhov kev pabcuam siab tshaj plaws ntawm Hastelloy B-3 yog dab tsi?

Hauv cov huab cua oxidising xws li huab cua, txog 540 degrees Celsius yog lub qab nthab. Hauv kev txo cov pa roj los yog lub tshuab nqus tsev, B-3 tuaj yeem siv ntau dua. Ntev-lub sij hawm kev pab cuam nyob rau hauv lub 550-900 degrees Celsius nag lossis daus qhov rais tseem yuav tsum tau zam rau lub siab-tswj Cheebtsam; Qhov kom zoo dua ntawm B-3 yog qhov kis tau tus mob thaum lub sij hawm vuam tsis ua rau embrittlement.

14. Hastelloy B-3 puas tuaj yeem siv rau hauv sulfuric acid?

Yog lawm, nyob rau hauv cov ntshiab uas tsis yog -oxidising sulfuric acid nyob rau hauv nruab nrab concentration thiab kub, qhov twg cov nqi nyob rau hauv boiling 10% acid nyob rau hauv qab no 0.1 mm / xyoo. Nws tsis haum rau sulfuric acid uas muaj cov kab mob oxidizing. Rau kev sib xyaw lossis oxidizing acid, siv Hastelloy C-276 lossis C-22.

15. Puas yog cov ntsiab lus molybdenum ntau dua ntawm B-3 txhim kho hydrochloric acid tsis kam?

Tsis ntsuas nyob rau hauv cov kua qaub ntshiab, vim tias ob qib twb tsim tib lub molybdenum - nplua nuj zaj duab xis thiab ob qho tib si khiav qis dua 0.1 hli / xyoo ntawm ambient mus rau 70 degrees Celsius. Lub qhov rais molybdenum siab dua hauv B-3 tshwm sim los hloov txoj kev nag lossis daus mus rau Ni3Mo, tsis yog txhawm rau txhim kho corrosion.

16. Qhov txawv ntawm Ni4Mo thiab Ni3Mo yog dab tsi?

Ob qho tib si raug txiav txim sib txuas ntawm nickel thiab molybdenum uas tuaj yeem tsim hauv cov hlau nplej thaum nws txias. Ni4Mo yog qhov nrawm- sib sau ua ke, siab heev embrittling daim ntawv uas plagues B-2. Ni3Mo cov ntaub ntawv qeeb qeeb dua thiab yog theem B-3 yog tsim los kom haum. Kev nag lossis daus qeeb txhais tau hais tias cov hlau tuaj yeem dhau los ntawm qhov ntsuas kub txaus ntshai yam tsis muaj kev puas tsuaj.

17. Puas yog B-2 thiab B-3 xav tau kev daws teeb meem ntawm cov khoom siv hauv paus?

Yog lawm. Ob leeg tau muab rau hauv cov tshuaj -annealed thiab quenched mob, feem ntau 1,050-1,100 degrees Celsius ua raws li los ntawm cov dej ceev ceev. Qhov no dissolves tej precipitate thiab freezes molybdenum nyob rau hauv kev daws. Ib qho kev ua haujlwm kub los yog hnyav ua haujlwm yuav tsum tau ua raws li kev rov ua dua.

18. Hastelloy B-3 piv rau C-276: Kuv yuav xaiv li cas?

Xaiv B-3 rau ntshiab txo cov kua qaub, saum toj no tag nrho cov hydrochloric acid ntawm txhua qhov concentration thiab kub. Xaiv C-276 thaum cov kwj dej muaj oxidising hom, thaum cov kua qaub sib xyaw, lossis thaum tsis muaj ferric thiab cupric paug tsis tuaj yeem raug cais tawm. C-276 cov ntsiab lus chromium muab nws cov oxidising tsis kam uas B alloys txhob txwm ua lag luam tawm.

19. Hastelloy B-3 puas tuaj yeem siv rau hauv hydrofluoric acid lossis sib xyaw HCl + HF?

Nws tuaj yeem ua tau, tab sis ib qho kev daws teeb meem yog ib txwm pom zoo ua ntej kev pabcuam thiab lub luag haujlwm yuav tsum raug kuaj xyuas los ntawm kev sim, vim tias tus cwj pwm fluoride yog qhov tshwj xeeb rau kev xav thiab kub. Ntau tus neeg tsim qauv nyiam C-276 lossis Monel rau cov kwj deg fluoride.

20. Kuv yuav ua li cas thiaj paub tseeb tias kuv tau txais Hastelloy B-3 tiag?

Yuav tsum tau daim ntawv pov thawj zeb kuaj rau EN 10204 3.1 lossis 3.2 qhia UNS N10675 nrog chromium nyob rau hauv 1.0-3.0% ntau thiab carbon ntawm lossis qis dua 0.01%, ces khiav 100% cov ntaub ntawv zoo los ntawm XRF lossis OES ntawm txhua daim ntawm daim ntawv txais nyiaj. B-2 thiab B-3 yog qhov pom kev zoo ib yam, thiab cov khoom siv mislabelled yog qhov paub txog kev lag luam.