1. Nyias-Gauge Forming: Dab tsi yog cov teeb meem tshwj xeeb ntawm kev tsim Hastelloy B-3 daim ntawv rau hauv cov tshuaj reactor complex, thiab lub caij nplooj ntoos hlav rov qab cuam tshuam li cas ntawm qhov raug?
Q: Peb tab tom tsim cov baffles thiab cov tais rau ib qho hydrochloric acid stripping kem siv 3 hli tuab Hastelloy B-3 daim ntawv. Cov qauv tsim muaj xws li cov flanges complex thiab stiffening tav. Peb cov neeg ua haujlwm xovxwm nres tau tawm tsam nrog cov kaum sab xis tsis sib haum. Qhov no puas yog ib qho teeb meem ntawm cov khoom siv lossis cov teeb meem kev siv cuab yeej?
A: Qhov no yuav yog qhov sib xyaw ua ke ntawm ob qho tib si, tab sis lub hauv paus ua rau muaj nyob rau hauv cov khoom sib txawv ntawm Hastelloy B-3 daim ntawv. Tsis zoo li cov hlau tsis muaj steel, B-3 nthuav tawm lub zog muaj zog ntau dua thiab muaj qhov sib txawv ntawm lub caij nplooj ntoos hlav-rov qab uas yuav tsum tau them nyiaj rau hauv cov cuab yeej thiab cov txheej txheem tsim.
Caij nplooj ntoos hlav- Rov qab Mechanism:
Hastelloy B-3 ua haujlwm hnyav sai. Thaum koj khoov daim ntawv, cov fibers sab nraud stretch thiab harden. Thaum tso tawm ntawm lub zog dabtsi yog khoov, qhov elastic feem ntawm qhov deformation sim rov qab mus rau nws qhov qub, "caij nplooj ntoos hlav rov qab" lub kaum sab xis.
Quantifying qhov txawv:
Austenitic Stainless Steel (304/316): Lub caij nplooj ntoos hlav zoo ib yam- rov qab rau 90℃khoov yuav xav tau tshaj - khoov rau 92℃lossis 93℃.
Hastelloy B-3: Vim nws lub zog tawm los ntau dua (feem ntau 350-400 MPa annealed vs . 240 MPa rau 304), lub caij nplooj ntoos hlav-rov qab yog qhov tseem ceeb tshaj. Rau 90℃khoov, koj yuav tsum tau khoov mus rau 95℃lossis txawm 98 degree, nyob ntawm qhov khoov vojvoog thiab tuab.
Tooling Solutions:
Cua Bending vs. Bottoming: Cua khoov (qhov twg cov punch tsis yuam cov ntawv mus rau hauv qab ntawm qhov tuag) yog ib txwm, tab sis lub caij nplooj ntoos hlav -rov qab yog txawv raws li cov khoom thickness kam rau ua. Rau qhov tseem ceeb ntawm qhov loj me ntawm B-3, qhov nyiaj npib lossis qis dua yog nyiam. Qhov no plastically deforms cov khoom ntawm lub vojvoog khoov, "teeb" lub kaum sab xis thiab txo lub caij nplooj ntoos hlav-rov qab.
Khoov Radius (Qhov Tseem Ceeb Tseem Ceeb):
Txoj cai ntawm tus ntiv tes xoo: Rau B-3 daim ntawv, qhov tsawg kawg nkaus khoov vojvoog yuav tsum yog 2-3 npaug ntawm cov khoom tuab (2T txog 3T).
Kev pheej hmoo: Sim lub vojvoog nruj dua (1T) yuav ua rau tawg ntawm sab nrauv vim tias cov khoom tsis tuaj yeem elongate txaus ua ntej mus txog nws txoj haujlwm - kev txwv hardening. Cov fibers sab nrauv yuav muab rhuav tshem.
Tuag Qhib: Qhov dav ntawm qhov qhib tuag (V- tuag) yuav tsum raug xam kom raug. Tus qauv qauv yog V- tuag=8x cov khoom tuab. Rau B-3, qhov qhib qhov dav me ntsis txo qhov kev ntxhov siab thiab tso cai rau cov khoom ntws sib npaug, txo qhov kev pheej hmoo ntawm kev tawg.
Qhov "Batch Consistency" Factor:
B-3 daim ntawv muab rau hauv cov tshuaj annealed mob yuav tsum zoo ib yam. Txawm li cas los xij, yog tias koj muaj ntau daim ntawv los ntawm cov cua sov sib txawv, qhov me me ntawm cov nplej loj lossis chemistry tuaj yeem cuam tshuam rau lub caij nplooj ntoos hlav-rov qab. Ib txwm ua qhov kev sim khoov ntawm ib qho qauv los ntawm cov ntawv tshwj xeeb ua ntej teeb tsa kev tsim khoom.
2. Welding Thin Sheet: Hauv GTAW vuam ntawm Hastelloy B-3 daim ntawv hauv qab 2 hli tuab, koj yuav ua li cas tiv thaiv "qab zib" (oxidation) ntawm sab nraub qaum yam tsis siv cov roj rov qab, muab cov hlau rhiab heev rau oxidizing tej yam kev mob?
Q: Peb tab tom vuam 1.6mm Hastelloy B-3 daim ntawv rau daim ntawv thov kev siv tshuaj. Peb tsis tuaj yeem tau txais cov khoom siv purging hauv lub rooj sib txoos me me los tiv thaiv lub nraub qaum ntawm qhov vuam. Peb puas yuav tau txais oxidation, thiab yog tias muaj, qhov ntawd cuam tshuam li cas rau kev tiv thaiv corrosion hauv HCl kev pabcuam?
A: Hauv nyias - ntsuas Hastelloy B-3 daim ntawv vuam, rov qab oxidation (qab zib) yog ib qho kev txhawj xeeb loj, tab sis tsis yog rau tib yam li stainless hlau. Rau B-3, qhov tshwm sim ntawm oxidation muaj peev xwm hnyav dua vim yog cov hlau tshwj xeeb chemistry thiab kev pabcuam ib puag ncig.
Oxidation Mechanism:
Hastelloy B-3 muaj chromium tsawg heev (1-3%) thiab siab molybdenum (28-30%). Thaum lub nraub qaum ntawm lub vuam raug rau huab cua ntawm vuam kub (siab tshaj 600 degree):
Molybdenum Oxide Tsim: Cov molybdenum tsim cov oxides tsis muaj zog (MoO3) uas tuaj yeem vaporize, depleting saum npoo ntawm molybdenum.
Nickel Oxide Scale: Ib qho hnyav, tsaus nti ntawm cov ntawv nickel oxide.
Corrosion Consequence:
Yog tias koj siv daim ntawv no rau kev pabcuam hydrochloric acid, qhov tsis yog -purged backside yog qhov tseem ceeb tsis ua haujlwm.
Molybdenum Depletion: Cov cheeb tsam hauv qab oxide nplai yog depleted ntawm molybdenum. Txij li thaum molybdenum yog cov khoom uas muab kev tiv thaiv corrosion hauv HCl, "molybdenum- tshaib plab" txheej yuav corrode sai heev thaum raug cov kua qaub.
Galvanic Cell: Cov nplai oxidized nws tus kheej, yog tias tsis tshem tawm tag nrho, tuaj yeem tsim ob peb galvanic nrog cov hlau huv huv, ua kom nrawm nrawm hauv zos.
Cov kev daws teeb meem thaum rov qab Purging yog ua tsis tau:
Flux Backing (Lwm txoj rau Gas): Tshwj xeeb rov qab fluxes (feem ntau cawv-raws li pastes uas muaj fluoride compounds) tuaj yeem siv rau sab nraub qaum ua ntej vuam. Cov fluxes yaj thiab tsim cov txheej txheem tiv thaiv slag uas tsis suav nrog oxygen thiab absorbs oxides. Tom qab vuam, cov dej seem yuav tsum tau muab ntxuav kom huv si (dej ntxuav lossis txhuam) vim nws tuaj yeem ua rau hygroscopic thiab corrosive.
Weld Backing Tape (Ceramic los yog Copper): Ib qho tooj liab thaub qab (dej-txias yog tias ua tau) tuaj yeem tuav nruj nreem rau sab nraub qaum. Cov tooj liab ua raws li lub dab dej kub, ua kom txias txias ntawm lub pas dej ua ke thiab txo lub sijhawm rau oxidation. Ceramic backing tuav kuj tseem siv tau tab sis feem ntau rau kev tsim cov hlaws rov qab, tsis yog rau kev tiv thaiv oxidation nkaus.
Txais thiab Tshem Tawm (Lub Siab- Kev Xaiv Risk): Yog tias koj txuas tsis muaj kev tiv thaiv, koj yuav tau txais oxide. Qhov no oxideyuav tsumyuav tsum tau muab tshem tawm (sib tsoo nrog rau cov npib tsib xee{0}} alloy log) thiab qhov chaw yuav tsum tau kuaj tshuaj (xws li, tooj liab sulfate test) kom tsis txhob muaj hlau lossis oxide paug. Txawm li cas los xij, koj tsis tuaj yeem kho cov molybdenum uas tau ploj mus rau vaporization.
Txoj Kev Ua Zoo Tshaj Plaws: Txawm tias rau cov rooj sib txoos me me, kev tshem tawm muaj tswv yim tsim nyog rau kev siv zog. Kev siv cov kais dej soluble purge (daim ntawv uas yaj hauv dej) los yog daim kab xev - tawm ntawm cov chav me kom muaj argon yog qhov zoo dua rau kev pheej hmoo ntawm corrosion kev ncaj ncees ntawm cov vuam.
3. Hydrochloric Acid Vapor Service: Rau cov kab hauv kab uas raug HCl vapor saum cov kua qaub dew point, Hastelloy B-3 daim ntawv puas muaj kev tiv thaiv zoo ib yam li nws ua hauv cov kua immersion service?
Q: Peb tab tom nyob rau sab sauv ntawm kab ntawv hydrochloric acid nrog 2 hli Hastelloy B-3 daim ntawv. Ntu no tuav HCl vapor ntawm 180 degree, zoo tshaj qhov dej lwg. Puas yog cov txheej txheem corrosion txawv nyob rau hauv vapor theem, thiab peb puas yuav tsum tau txhawj xeeb txog kev tawm tsam sib txawv?
A: Lub vapor theem saum toj no dew point nthuav tawm qhov sib txawv corrosion ib puag ncig piv rau cov kua immersion. Thaum Hastelloy B-3 tseem yog qhov kev xaiv zoo tshaj plaws, cov txheej txheem tiv thaiv thiab kev hem thawj yog txawv.
Corrosion Mechanism Hloov:
Hauv cov kua HCl, corrosion yog cov txheej txheem electrochemical uas yuav tsum tau muaj cov electrolyte. Nyob rau hauv kub, qhuav vapor saum toj no dew point, thawj hem hloov mus rau:
Direct Chemical Attack: Ntawm qhov kub siab, cov roj HCl qhuav tuaj yeem cuam tshuam ncaj qha nrog cov hlau nto, tsim cov hlau chlorides. Qhov no yog tshuaj, tsis yog electrochemical, tshuaj tiv thaiv.
Condensation Risks: Qhov chaw txaus ntshai tseem ceeb tsis yog qhov vapor ntau, tab sis txhua qhov chaw uas qhov kub poob qis dua qhov dej lwg. Yog hais tias muaj qhov txias me ntsis ntawm lub hauv ob sab phlu (vim tsis zoo rwb thaiv tsev los yog cov cua txias sab nraud), ib zaj duab xis nyias ntawm cov concentrated hydrochloric acid tuaj yeem ua rau hws.
B-3 Kev Ua Haujlwm hauv Vapor:
Hastelloy B-3 feem ntau ua tau zoo heev nyob rau hauv kub, qhuav HCl vapor. Yog tsis muaj ib tug aqueous electrolyte txhais tau hais tias cov electrochemical corrosion hlwb tsis tuaj yeem tsim. Tus nqi corrosion feem ntau yog tsawg-feem ntau tsawg dua 0.05 hli / xyoo.
Kev hem tshwj xeeb los saib xyuas:
Hlau Chloride Tsim: Ntawm qhov sib cuam tshuam ntawm cov pa kub thiab cov hlau, nickel thiab molybdenum chlorides tuaj yeem tsim. Cov chlorides no muaj cov ntsiab lus melting tsawg thiab tuaj yeem hloov pauv tau. Hauv qhov xwm txheej hnyav, qhov no tuaj yeem ua rau muaj qhov tshwm sim hu ua "hlau plua plav" yog tias muaj cov pa roj carbon monoxide (txawm tias tsawg dua hauv HCl kev pabcuam).
Thermal Cycling: Yog hais tias lub kem kaw thiab txias, noo noo los ntawm huab cua tuaj yeem ua ke nrog cov tshuaj chloride seem ntawm cov ntawv saum npoo los tsim cov corrosive hydrochloric acid thaum lub sijhawm tsis ua haujlwm. Kev tshem tawm nitrogen kom huv si thiab qhuav -tawm txheej txheem thaum kaw yog qhov tseem ceeb.
Cov lus pom zoo tsim:
Nto tiav: Ib daim ntawv du, huv si (2B tiav lossis zoo dua) yog qhov muaj txiaj ntsig zoo vim nws muab cov chaw tsawg dua rau chloride ntsev deposition.
Rwb thaiv tsev: Xyuas kom cov rwb thaiv tsev sab nraud ntawm sab zoo meej. Txhua qhov chaw txias ntawm lub plhaub sab nraud yuav tsim qhov chaw txias txias ntawm sab hauv B-3 hauv ob sab phlu, ua rau muaj kev phom sij ntawm HCl vapor.
Thickness Monitoring: Txawm tias muaj tus nqi qis dua, daim ntawv 2 hli muab kev txwv tsis pub xeb. Xav txog kev txhim kho corrosion probes lossis ultrasonic soj ntsuam cov ntsiab lus txhawm rau taug qab txhua yam kev xav tau ntawm cov hlau poob.
4. Kev Kho & Rov Kho Dua: Cov ntawv Hastelloy B-3 puas tuaj yeem siv los kho lossis overlay cov khoom siv carbon steel uas twb muaj lawm hauv HCl kev pabcuam, thiab dab tsi yog qhov txaus ntshai ntawm cov hlau dilution?
Q: Peb muaj lub qub carbon steel cia tank rau hydrochloric acid uas yog to. Peb tsis tuaj yeem hloov nws yooj yim. Peb puas tuaj yeem welding nyias Hastelloy B-3 daim ntawv ncaj qha mus rau cov pa roj carbon steel li hauv ob sab phlu (wallpapering), thiab yuav tsum tau ceev faj dab tsi los tiv thaiv cov hlau los ntawm kev puas tsuaj B-3's corrosion resistance?
A: Yog lawm, "wallpapering" los yog siv lub nyias Hastelloy B-3 daim ntawv hauv ob sab phlu rau lub tank carbon steel uas twb muaj lawm yog cov txheej txheem kho kom zoo thiab raug nqi zoo. Txawm li cas los xij, qhov kev pheej hmoo ntawm cov hlau dilution thaum lub sij hawm vuam uas txuas B-3 rau cov hlau yog qhov tseem ceeb tshaj plaws uas txiav txim siab ua tiav lossis tsis ua tiav.
Hlau Dilution Catastrophe:
Yog tias koj txuas ncaj qha rau B-3 daim ntawv rau cov pa roj carbon steel uas siv cov qauv txuas txuas (xws li, lub ntsaws vuam los ntawm lub qhov B-3), lub pas dej ua ke yuav yaj ob daim ntawv B-3 thiab cov pa roj carbon steel rov qab.
Chemistry Shift: Cov txiaj ntsig tau txais txiaj ntsig yuav yog qhov sib xyaw ntawm npib tsib xee- molybdenum (los ntawm B-}3) thiab hlau (los ntawm carbon steel). Qhov no tsim ib qho siab - hlau, qis-molybdenum cheeb tsam.
Hom Tsis Ua Haujlwm: Hauv hydrochloric acid, cov hlau no - nplua nuj tsis muaj corrosion kuj. Nws yuav yaj sai heev, tsim ib tug pinhole xau ncaj qha ntawm qhov txuas taw tes. Cov kua qaub yuav tom qab hauv ob sab phlu, corroding cov pa roj carbon steel thiab ua rau hauv ob sab phlu thiab ua tsis tiav.
Kev daws: Cov txheej txheem "Strip Lining" lossis "Ob chav txheej" txheej txheem:
Txhawm rau kom tsis txhob dilution, koj yuav tsum cais cov B-3 ntawm cov pa roj carbon steel hauv cov txheej txheem vuam. Ntawm no yog cov txheej txheem kev lag luam-tus qauv:
Carbon Steel Kev Npaj: Grit- tawg cov pa roj carbon steel tank sab hauv rau cov hlau dawb (SSPC-SP5). Tag nrho cov xeb thiab nplai yuav tsum tau muab tshem tawm.
Cov Kab Txuas Txuas (Cov Txheej Tsis Muaj): Tsis yog vuam B-3 ncaj qha rau cov hlau, koj thawj zaug vuam me metxuas stripsntawm cov nickel alloy sib xws (feem ntau Hastelloy C-276 lossis txawm B-3 nws tus kheej)ncaj qha mus rau carbon steel. Cov strips no tsuas yog welded raws lawv cov npoo, ncaj qha rau cov hlau.
Cov Ntawv B-3: Cov nplooj ntawv Hastelloy B-3 tom qab ntawd muab tso rau hauv cov ntawv txuas.
Kev rho tawm Weld: Cov nplooj B-3 yog weldedtsuas yog mus rau qhov txuas strips, tsis yog carbon steel. Lub weld koom nrog B-3 daim ntawv rau daim ntawv txuas yog "dilution-dawb" weld-ob cov ntaub ntawv yog npib tsib xee alloys, yog li kev tiv thaiv corrosion yog khaws cia.
Seal Welds thiab Vents:
Tag nrho B-3 daim ntawv- rau daim ntawv seams yog welded tag nrho (feem ntau nrog ERNiMo-7 los yog ERNiMo-10 muab tub lim) los tsim ib tug nruam corrosion barrier.
Cov qhov me me (qhia rau- cov lus dab neeg) feem ntau yog drilled los ntawm cov pa roj carbon steel lub plhaub kom tso cai rau cov hydrogen uas tsim tom qab hauv ob sab phlu kom khiav tawm thiab qhia tias lub hauv paus tseem ceeb puas tau xau.
Kev txheeb xyuas:
Tom qab kev teeb tsa, kev ntsuas hluav taws xob (siab- qhov ntsuas hluav taws xob hnub so) tau ua tiav ntau dua 100% ntawm cov kab hauv qab kom ntseeg tau tias tsis muaj pinholes lossis qhov liab qab hauv daim ntawv B-3 uas yuav nthuav tawm cov pa roj carbon steel.
5. Txiav & Shearing: Qhov kev coj ua zoo tshaj plaws rau shearing Hastelloy B-3 daim ntawv yog dab tsi kom tsis txhob ua hauj lwm-hardened npoo uas tawg thaum lub sij hawm tom ntej los yog vuam?
Q: Peb tab tom txiav Hastelloy B-3 nplooj ntawv kom loj rau ntawm guillotine shear ua ntej khoov. Peb tab tom pom cov micro-cracks raws ntug sheared, tshwj xeeb tshaj yog ntawm cov ntawv tuab (4-5mm). Cov kab nrib pleb no nthuav tawm thaum peb sim vuam lossis khoov ntug. Peb yuav tiv thaiv qhov no li cas?
A: Cov micro- tawg uas koj tab tom saib yog cov tsos mob classic ntawm shearing -induced ua hauj lwm hardening thiab ductile rupture nyob rau hauv ib tug siab - molybdenum alloy. Hastelloy B-3 muaj qhov ua haujlwm siab-hardening tus nqi, thiab cov txheej txheem shearing tuaj yeem tsim kom muaj qhov deformed hnyav, nkig thaj tsam ntawm ntug txiav uas ua rau tawg.
Shearing Mechanism hauv B-3:
Thaum lub tshuab txiav txiav los ntawm B-3 daim ntawv, nws tsis "txiav" hauv kev nkag siab ntawm lub saw; nws induces ib pob txha. Cov txheej txheem muaj xws li:
Plastic Deformation: Cov hniav nkag mus, ua haujlwm - hardening cov khoom.
Fracture: Cov khoom nws thiaj li kua muag raws lub dav hlau shear.
Burr Zone: Ntawm B-3, qhov chaw tawg no feem ntau yog jagged thiab muaj cov kua muag micro uas nthuav tawm hauv qab ntawm qhov pom.
Kev tiv thaiv thiab txo cov tswv yim:
Blade Clearance yog qhov tseem ceeb:
Rau cov hlau tsis muaj hlau, cov hniav tshem tawm yuav raug teeb tsa ntawm 5-8% ntawm tuab.
Rau Hastelloy B-3, yuav tsum muaj kev tshem tawm nruj dua (3-5%). Qhov no txo qis qhov deformation cheeb tsam ua ntej tawg, ua kom huv si nrog tsawg micro kua muag. Cov hniav lawv tus kheej yuav tsum tau ntse thiab tshwj xeeb hauv av rau nickel alloys.
Txoj cai "Machine Edge":
Forming: Yog hais tias koj npaj yuav khoov daim ntawv, lub sheared ntug yuav tsumtsis yognyob rau sab nro (sab nraum) ntawm qhov khoov. Cov micro- cracks yuav ua raws li kev ntxhov siab concentrators thiab propagated rau hauv ib tug pom tawg. Muab cov ntug sheared rau ntawm sab compression (sab hauv) ntawm qhov khoov, lossis zoo dua, tshuab nws tawm.
Rau Vuam: Tsis txhob welding ncaj qha rau ntawm ntug sheared yam tsis tau npaj nws. Cov micro- tawg yuav ua rau porosity thiab tsis muaj fusion nyob rau hauv lub vuam.
Ntug Kev Npaj (Cov kauj ruam yuav tsum tau ua):
Machining / Sib Tsoo: Ua ntej ib qho tseem ceeb sib sau los yog vuam, lub npoo sheared yuav tsum tau ntxuav. Tshuab lub ntug ntawm lub zeb los yog siv ib tug tshwj xeeb abrasive siv grinder (nrog txhuas oxide los yog silicon carbide logmob siab rau nickel alloys) kom tshem tawm yam tsawg kawg 1 hli ntawm lub ntsej muag sheared. Qhov no tshem tawm cov haujlwm- cov txheej tawv tawv thiab micro- tawg tsam.
Deburring tsis txaus: tsuas yog khob tawm ntawm qhov burr tsis tshem tawm qhov kev puas tsuaj subsurface.
Lwm txoj kev txiav txiav:
Plasma Txiav: Tsis pom zoo rau nyias B-3 daim ntawv. Lub tshav kub cuam tshuam yog loj thiab tsim ib qho nyuaj, nkig ntug uas yuav tsum tau machined tag nrho.
Waterjet Txiav: Ib qho kev xaiv zoo heev. Waterjet tsim qhov txias txias uas tsis muaj cua sov- thaj tsam cuam tshuam thiab tsis ua haujlwm hnyav. Lub ntug yog huv si thiab npaj txhij rau kev sib sau los yog vuam nrog tsawg heev npaj. Rau cov duab nyuaj lossis cov npoo tseem ceeb, waterjet yog txoj kev nyiam.
Abrasive Saw: Ib qho pom txias nrog lub ntsej muag ntse, nplooj siab thiab cov dej txias kom zoo tuaj yeem tsim cov ntug zoo dua li shearing, txawm tias nws qeeb dua.
