1. Cov txheej txheem tsim khoom: Cov txheej txheem kos duab txias rau Hastelloy B-2 kav dej yog dab tsi, thiab vim li cas nws thiaj li nyiam rau kev siv precision?
Q: Peb tab tom nrhiav Hastelloy B-2 cov kav dej rau kev siv hluav taws xob sib hloov pauv uas yuav tsum tau ua kom nruj me ntsis. Peb tus neeg muag khoom pom zoo kom cov kav dej txias txias dua kub tiav. Dab tsi yog cov txheej txheem kos duab txias, thiab nws muaj txiaj ntsig dab tsi rau cov hlau no?
A: Kev kos duab txias yog cov txheej txheem tsim khoom muaj txiaj ntsig zoo rau Hastelloy B-2 cov kav dej, tshwj xeeb tshaj yog thaum qhov tseeb qhov tseeb, qhov tiav, thiab cov khoom siv kho tshuab tseem ceeb heev.
Txheej Txheem Txias Drawing:
Pib Khoom (Hollow):
Pib raws li qhov kub tiav los yog extruded yeeb nkab (qee zaus hu ua "hollow").
Cov khoom yog nyob rau hauv cov tshuaj annealed mob.
Kev npaj:
Cov yeeb nkab yog pickled kom tshem tawm nplai.
Ib qho kawg yog swaged los yog taw tes kom tso cai tuav los ntawm lub tsheb thauj khoom.
Ib txheej roj nplua nyeem yog siv (feem ntau oxalate lossis tooj liab txheej rau nickel alloys).
Kev kos duab (The Critical Step):
Qhov kawg taw tes yog pub los ntawm kev tuag thiab tuav los ntawm lub tsheb thauj khoom.
Cov yeeb nkab yog rub los ntawm qhov tuag, uas txo nws txoj kab uas hla.
Internal mandrel (nyob ruaj ruaj los yog ntab) tswj lub sab hauv kab thiab phab ntsa thickness.
Kev txo qis ib qho dhau: Feem ntau 10-30%, nyob ntawm cov hlau thiab lubrication.
Intermediate Annealing:
Hastelloy B-2 ua haujlwm hnyav sai.
Tom qab ib lossis ob daim duab hla dhau, cov yeeb nkab yuav nyuaj heev rau kev txo qis ntxiv.
Nws yuav tsum tau tov annealed (1060-1120 degree, dej quench) kom rov ductility.
Ntau qhov kos-anneal cycles yuav tsum tau kom ncav cuag qhov ntev kawg.
Kev ua tiav kawg:
Qhov kawg dhau ua tiav qhov ntev thiab qhov chaw tiav.
Kev daws zaum kawg annealing (yog tias xav tau) lossis kev ntxhov siab.
Ncaj, txiav, thiab tshuaj xyuas.
Qhov zoo ntawm Cold Drawn Pipes rau Hastelloy B-2:
| Qhov zoo | Vim Li Cas Nws Tseem Ceeb |
|---|---|
| Precision Tolerances | OD: ± 0.005 "los yog zoo dua; Phab ntsa: ± 10% lossis zoo dua |
| Nto tiav | 32-63 Ra microinches raug (vs . 125+ rau kub tiav) |
| Concentricity | Txhim kho phab ntsa uniformity (90% + yam tsawg kawg nkaus) |
| Mechanical Properties | Yuav ua kom haum (annealed, stress relieved, los yog tag nrho nyuaj) |
| Ntev ntev | Coilable lengths ua tau rau me me diameters |
| Dimensional Consistency | Zoo tagnrho rau tshav kub exchanger raj bundles |
Yog vim li cas Cold Drawing yog nyiam rau cov ntawv thov Precision:
Thaum tshav kub kub Exchanger Tubes: Yuav tsum tau nruj kam rau ua rau lub raj ntawv lub qhov haum-up.
Instrumentation Lines: Demand precise ID for flow control.
Hydraulic Systems: Xav tau cov phab ntsa tuab zoo ib yam rau kev ntsuas siab.
Aerospace Cheebtsam: Yuav tsum muaj qhov ntev thiab qhov chaw tiav.
Kev sib tw B-2:
Hastelloy B-2 tus nqi ua haujlwm siab txhais tau tias:
Ntau qhov nruab nrab anneals yuav xav tau ntau dua li cov hlau tsis muaj steel.
Kev kos duab muaj zog dua.
Lubrication yog qhov tseem ceeb los tiv thaiv galling.
Cov cuab yeej hnav yog nrawm dua.
Kev kuaj xyuas zoo thaum tsim khoom:
| Theem | Kev tshuaj xyuas |
|---|---|
| Tom qab txhua tus kos | Dimensional checks, nto tshuaj xyuas |
| Tom qab annealing | Kev kuaj hardness, microstructure |
| Kawg | UT/ET, hydrotest, daim ntawv pov thawj qhov ntev |
Lus Qhia:
Rau precision daim ntawv thov, qhia:
* "Hastelloy B-2 cov kav dej yuav tsum txias txias rau qhov kawg qhov ntev ntawm ASTM B622. Tolerances: OD ± 0.005", phab ntsa ± 10%. Nto tiav 63 Ra siab tshaj plaws. Cov khoom yuav tsum muab nkag rau hauv cov tshuaj annealed mob tom qab kos zaum kawg, nrog rau daim ntawv pov thawj tag nrho. "*
Kev pom zoo:
Rau koj cov khoom siv hluav taws xob zoo tshaj plaws, txias kos Hastelloy B-2 kav dej yog qhov kev xaiv raug. Cov txheej txheem kos duab txias muab qhov tseeb qhov tseeb thiab qhov zoo ntawm qhov xav tau rau kev txhim khu kev qha raj ntawv sealing thiab kev ua haujlwm zoo ib yam. Qhia ntau lub voj voog kos-anneal nrog cov tshuaj kawg annealing rau kev pom zoo corrosion.
2. Metallurgical Condition: Dab tsi yog qhov txawv ntawm "raws li{1}}kos" thiab "solution annealed" Hastelloy B-2 txias drawn kav, thiab qhov twg yog qhov tseeb rau HCl kev pabcuam?
Q: Peb tau txais ob nqe lus rau Hastelloy B-2 cov kav dej txias txias- ib qho rau "raws li- kos" thiab ib qho rau "kev daws teeb meem." Raws li - kos yog tsawg dua. Peb puas tuaj yeem siv cov yeeb nkab kos rau peb daim ntawv thov hydrochloric acid, lossis puas yuav tsum tau annealing?
A: Qhov no yog ib lo lus nug tseem ceeb uas cuam tshuam ncaj qha rau kev nyab xeeb thiab lub neej ntev ntawm koj HCl system. Cov lus teb luv luv yog: Rau kev pabcuam hydrochloric acid, kev daws cov yeeb nkab annealed yog qhov yuav tsum tau ua. Raws li - kos cov yeeb nkab yuav ua tsis tiav ntxov.
Qhov txawv Metallurgical:
| Qhov xwm txheej | Microstructure | Hardness | Residual Stress | Corrosion Resistance |
|---|---|---|---|---|
| Raws li - kos | Ua haujlwm txias, elongated nplej | Siab (25-40 HRC) | Siab tensile kev nyuaj siab | Txo - tsis zoo |
| Tshuaj annealed | Recrystallized, equiaxed nplej | Tsawg (85-95 HRB) | Tsawg kawg | Zoo heev - rov zoo tag nrho |
Vim li cas As -Drawn Fail hauv HCl Service:
Ua hauj lwm hardened nto:
Kev kos duab txias ua haujlwm hnyav heev- ua kom cov yeeb nkab tawv.
Ua haujlwm-Hardened Hastelloy B-2 muaj qhov sib txawv corrosion dua li cov khoom siv annealed.
Hauv HCl, kev ua haujlwm- txheej tawv tawv corrodes nyiam thiab nrawm.
Residual Tensile Stresses:
Kev kos duab qhia txog siab tensile residual stresses nyob rau hauv cov yeeb nkab.
Cov kev ntxhov siab no tuaj yeem tshaj qhov tawm los ntawm lub zog hauv zos.
Ua ke nrog HCl, kev ntxhov siab corrosion tawg (SCC) ua tau.
Ordering Susceptibility:
Txias- ua haujlwm B-2 yog qhov cuam tshuam rau kev txiav txim siab (embrittlement) yog tias raug kub nruab nrab.
Txawm tias qhov kub ntawm lub hnub ntawm cov yeeb nkab hauv qhov chaw cia tuaj yeem ua rau kev txiav txim siab txias heev - cov khoom ua haujlwm.
Tsis yog -Uniform Microstructure:
Sab nrauv (feem ntau ua haujlwm) thiab sab hauv tuaj yeem muaj cov khoom sib txawv.
Qhov no tsim ib galvanic cell ntawm nto thiab core nyob rau hauv acid pab.
Txoj kev daws teeb meem Annealing:
Kev daws teeb meem zoo rau B-2 cov kav dej txias txias yuav tsum:
Kub: 1060-1120 ° F (1940-2050 ° F)
Sijhawm: Txaus rau ua tiav recrystallization (1 teev ib nti ntawm thickness)
Quench: ceev dej quenching los tiv thaiv kev txiav txim
Cov txiaj ntsig: Ua kom tiav recrystallization, kev ntxhov siab nyem, rov ua kom muaj zog corrosion
Thaum Raws li -Drawn Yuav Tau Txais:
Raws li - kos B-2 kav qee zaum siv rau:
Tsis yog -cov kev pabcuam corrosive (cov cuab yeej cua, inert gases)
Mechanical applications (kev txhawb nqa, kev taw qhia)
Ib ntus lossis luv luv - kev pabcuam sijhawm
Cov ntawv thov uas xav tau lub zog siab (yog tias tsis muaj kev txhawj xeeb)
Txawm hais tias rau cov ntawv thov no, feem ntau pom zoo kom txo kev ntxhov siab.
B-2 vs. B-3 Factor:
Yog tias koj xav tau kev lag luam ntawm txias kos tab sis kev ntseeg siab ntawm annealed, xav txog:
B-3 (UNS N10675) yog kev zam txim rau kev ua haujlwm txias.
B-3 qee zaum tuaj yeem siv rau hauv qhov chaw ua haujlwm txias rau cov kev pabcuam hnyav dua.
Txawm li cas los xij, rau HCl kev pabcuam, txawm tias B-3 yuav tsum tau muab tshuaj ntxiv.
Lus Qhia:
Rau HCl kev pabcuam, qhia meej:
* "Hastelloy B-2 txias drawn kav yuav tsum tau muab nyob rau hauv cov tshuaj annealed mob tom qab kawg daim duab. Annealing yuav tsum tau ua nyob rau hauv 1060-1120℃tom qab quenching dej ceev. Hardness yuav tsum yog 95 HRB siab tshaj plaws. Cov ntaub ntawv yuav tsum haum rau hydrochloric acid kev pab cuam." *
Kev txheeb xyuas:
Kom paub meej tias koj tau txais cov yeeb nkab annealed:
Hardness Test: Yuav tsum yog<95 HRB (as-drawn would be much harder).
Microstructure: Thov micrographs qhia equiaxed nplej.
Corrosion Test: ASTM G28 cov txiaj ntsig yuav tsum qhia tias tus nqi qis dua.
Kev pom zoo:
Rau koj daim ntawv thov hydrochloric acid, tsis txhob siv raws li - kos Hastelloy B-2 kav. Kev txuag nqi yog kev lag luam cuav-cov kav dej yuav ua tsis tiav ntxov, ua rau cov txheej txheem poob qis, kev nyab xeeb kev nyab xeeb, thiab cov nqi hloov pauv ntau tshaj qhov pib txuag nyiaj. Insist rau kev daws annealed mob nrog tag nrho cov ntaub ntawv.
3. Dimensional Tolerances: Qhov ntev npaum li cas tuaj yeem ua tiav nrog cov kav dej txias Hastelloy B-2, thiab vim li cas lawv tseem ceeb?
Q: Peb tab tom tsim cov khoom siv hluav taws xob zoo tshaj plaws siv Hastelloy B-2 raj uas yuav tsum tau muab khi rau hauv cov ntawv raj. Qhov ntev ntev npaum li cas peb tuaj yeem xav tau los ntawm cov kav dej txias, thiab peb yuav tsum qhia dab tsi los xyuas kom haum?
A: Cold drawn Hastelloy B-2 kav dej muaj qhov zoo tshaj plaws ntawm qhov tseeb, uas yog qhov tseem ceeb rau kev sib hloov cov raj xa hluav taws xob. Kev nkag siab txog qhov ua tau raws li qhov ua tau zoo thiab kev qhia kom raug ua kom ntseeg tau tias kev tsim khoom.
Achievable Tolerances:
| Dimension | Qib lag luam | Qib Precision | Kub Exchanger Qib |
|---|---|---|---|
| Sab nraud txoj kab uas hla | ±0.005" | ±0.003" | ±0.002" |
| Sab hauv Dia | ±0.005" | ±0.003" | ±0.002" |
| Phab ntsa Thickness | ±10% | ±7.5% | ±5% |
| Ovality | 0.010 "max | 0.005 "max | 0.003" max |
| Kev ncaj | 1/16 "rau 3 ft | 1/32 "rau 3 ft | 1/32 "rau 3 ft |
| Ntev | ±1/8" | ±1/16" | ±1/32" |
Vim li cas Tight Tolerances Matter rau Heat Exchangers:
Tube Sheet haum:
Cov raj yuav tsum xaub mus rau hauv cov ntawv raj qhov nrog qhov tsawg kawg nkaus (feem ntau 0.003-0.005 "tag nrho).
Kev xoob dhau: Kev hloov pauv tsis zoo, kev vibration.
nruj dhau: Tsis tuaj yeem txhim kho, lub raj puas.
Roller Expansion:
Tubes feem ntau yog cov menyuam nthuav dav rau hauv cov ntawv raj.
Cov phab ntsa tuab zoo ib yam ua kom zoo ib yam nthuav dav.
Kev hloov pauv ua rau qee lub raj xoob, lwm qhov dhau - nthuav dav (kua tawg).
Foob Welding:
Yog hais tias cov raj yog foob welded, zoo ib yam -up kom zoo ib yam weld zoo.
Gaps ua rau weld defects.
Flow Distribution:
Tus ID sib xws ua kom muaj kev sib txawv ntawm txhua lub raj.
Kev hloov pauv ua rau qee lub raj muaj dej ntws ntau dua, lwm qhov qis dua, txo kev ua haujlwm.
Cold Drawing Achieves Precision:
| Qhov xwm txheej | Yuav Ua Li Cas |
|---|---|
| OD tswj | Precision tuag nrog qhov tseeb geometry |
| ID tswj | Mandrel tswj (floating los yog tsau) |
| Phab ntsa uniformity | Balanced txo, lubrication kom zoo |
| Concentricity | Tsim nyog tuag thiab mandrel sib dhos |
| Nto tiav | Polished tuag, cov khoom huv si, lubrication kom zoo |
Specifications Tolerances:
Rau cov cua kub exchanger raj, qhia:
* "Hastelloy B-2 cov kav dej txias yuav tsum ua raws li cov hauv qab no kam rau ua:*
Sab nraud txoj kab uas hla: ± 0.002 "
Phab ntsa Thickness: ± 5%
Ovality: 0.003 "siab kawg
* Ncaj: 1/32 "hauv 3 ko taw *
* Ntev: ± 1/16 "(ntxiv rau kev tsim khoom) *
Nto tiav: 63 Ra siab tshaj OD thiab ID
Txhua qhov ntev yuav tsum tau lees paub ntawm txhua lub raj lossis ntau. "
Kev tshuaj xyuas:
| Dimension | Txoj kev tshuaj xyuas |
|---|---|
| OD | Micrometer, laser micrometer |
| ID | Cua gauges, pin gauges, ultrasonic |
| Phab ntsa | Ultrasonic thickness ntsuas, micrometer (txiav xaus) |
| Ovality | Rotating tube hauv V-block nrog qhov taw qhia |
| Kev ncaj | Ncaj ntug thiab feeler gauge |
| Nto tiav | Profilometer, pom kev sib piv |
Lub tswvyim "Lot":
Rau loj kub exchangers nrog ntau lub raj:
Tubes feem ntau yog tsim nyob rau hauv ntau ntau.
Txhua qhov yuav tsum muaj qhov sib npaug.
Daim ntawv pov thawj ntau yuav tsum suav nrog qhov ntsuas qhov tseeb, tsis yog "ua tau raws li spec."
Kev txiav txim siab tshwj xeeb rau Hastelloy B-2:
Ua Haujlwm Hardening: Cov txheej txheem kos duab ua haujlwm- hardening cov khoom. Yog tias koj xav tau cov mos mos (annealed) hlab rau khoov lossis nthuav dav, qhia qhov kawg annealing.
Caij nplooj ntoos hlav-rov qab: Hastelloy B-2 muaj qhov tseem ceeb caij nplooj ntoos hlav-rov qab. Tuag tsim yuav tsum suav rau qhov no kom ua tiav lub hom phiaj qhov ntev.
Galling: Cov ntsiab lus molybdenum siab ua rau muaj kev pheej hmoo siab galling. Lub lubrication zoo yog qhov tseem ceeb rau kev tswj xyuas qhov chaw tiav.
Kev pom zoo:
Rau koj lub tshav kub exchanger, qhia meej meej-qib txias kos Hastelloy B-2 kav nrog nruj OD thiab phab ntsa kam rau ua. Yuav tsum tau daim ntawv pov thawj seem ntawm txhua lub raj lossis ntau. Xav txog kev txiav txim ob peb lub raj ntxiv ntawm txhua qhov loj rau kev kuaj kom haum ua ntej tag nrho cov khoom. Yog tias lub raj khoov lossis cov menyuam nthuav dav tau npaj, xyuas kom cov kav dej nyob hauv qhov kev daws teeb meem annealed.
4. Nto Finish: Dab tsi saum npoo tiav tuaj yeem ua tiav nrog cov kav dej txias Hastelloy B-2, thiab vim li cas qhov chaw sab hauv yog qhov tseem ceeb?
Q: Peb daim ntawv thov muaj kev ua haujlwm siab - purity chemical processing qhov chaw hauv qhov chaw du yog qhov tseem ceeb los tiv thaiv cov khoom tsim thiab kev sib kis. Dab tsi sab hauv nto tiav peb tuaj yeem ua tiav nrog cov kav dej txias Hastelloy B-2, thiab nws ntsuas li cas?
A: Sab hauv qhov chaw tiav yog qhov tseem ceeb tsis zoo rau ntau cov kev siv tshuaj lom neeg, thiab cov kav dej txias Hastelloy B-2 tuaj yeem ua tiav qhov zoo ntawm qhov chaw zoo thaum tsim khoom.
Achievable Surface Finishes:
| Qib | Ra Range (Microinches) | Daim ntawv thov |
|---|---|---|
| Kev lag luam kos | 63-125 Ib | Lub hom phiaj dav dav, tsis yog - tseem ceeb |
| Precision kos | 32-63 Ib | Feem ntau cov tshuaj ua haujlwm |
| Smooth bore | 16-32 Ib | High-purity, qis- kev pab cuam fouling |
| Ultra{0}} du | 8-16 Ib | Pharmaceutical, semiconductor |
| Electropolished | 4-8 Ib | Ultra- siab purity, kev siv tseem ceeb |
Rau koj siab -kev ua tshuaj purity, lub hom phiaj 16-32 Ra ua tiav.
Vim li cas Internal Surface Finish Matters:
Cov khoom tsim tawm (Fouling):
Rough nto muab qhov chaw rau cov khoom adhesion.
Buildup txo qhov chaw ntws, insulates tshav kub hloov chaw.
tuaj yeem ua rau ntsaws rau hauv me me - cov kav dej.
Kev kis kab mob:
Rough nto ntxiab khoom ntawm batch.
Cov khoom uas raug kaw tuaj yeem kis cov kab mob tom ntej.
Tshwj xeeb tseem ceeb rau kev siv tshuaj thiab zaub mov.
Corrosion pib:
Deg irregularities tuaj yeem pib pitting corrosion.
Qhov chaw du muaj tsawg qhov chaw pib.
Hauv kev pabcuam HCl, cov npoo du ua rau lub neej ntev ntev.
Cleanability:
Qhov chaw du yog yooj yim dua los ntxuav (CIP / SIP txheej txheem).
Txo kev pheej hmoo ntawm cov kab mob loj hlob (pharmaceutical, biotech).
Flow yam ntxwv:
Smoother nto txo kev sib txhuam poob.
Cov qauv ntws zoo sib xws.
Cold Drawing cuam tshuam li cas rau saum npoo tiav:
| Qhov xwm txheej | Kev cuam tshuam ntawm Nto Finish |
|---|---|
| Tuag polish | Highly polished tuag hloov tag mus rau lub raj |
| Lubrication | Cov roj nplua nyeem kom zoo tiv thaiv qhov txhaws thiab sib tw |
| Txo tus nqi | Kev txo qis zoo ua kom du nto |
| Khoom siv huv si | Kev suav nrog tuaj yeem tsim qhov tsis xws luag |
| Cov cua sov | Oxidation tuaj yeem roughen nto |
Ua tiav Smooth Internal Surfaces:
Rau 16-32 Ra internal tiav:
Pib nrog Cov Khoom Siv Huv Huv: Siab- zoo nkauj strip nrog tsawg kawg nkaus.
Ntau Draws: Ob peb kos-anneal cycles nrog nce smoother tuag.
Thaum kawg Kos nrog Polished Mandrel: Sab hauv nto yog tsim tawm tsam ib tug heev polished mandrel.
Tswj Lubrication: Cov yeeb yaj kiab zoo ib yam tiv thaiv hlau - mus rau - hlau sib cuag.
Kev Tiv Thaiv Huab Cua Annealing: Yog tias qhov kawg annealing yuav tsum tau siv, siv hydrogen los yog lub tshuab nqus tsev los tiv thaiv oxidation.
Kev ntsuas kev ntsuas:
| Txoj kev | Kev piav qhia | Zoo tshaj rau |
|---|---|---|
| Profilometry (kev sib cuag) | Stylus traverses nto, ntsuas peaks/valleys | Txiav cov qauv, xaus |
| Optical profiles | Tsis yog - tiv tauj laser ntsuas | Cov qauv kuaj |
| Huab cua sib piv | Kev ntsuas siab poob vs | 100% ntau lawm (tsis yog-kev puas tsuaj) |
| Kev pom kev sib piv | Muab piv rau cov qauv roughness | Quick khw hauv pem teb checks |
| Kev tshuaj xyuas borescope | Kev kuaj pom qhov ntev ntev | Txheeb xyuas qhov tsis xws luag |
Specification Surface Finish:
Rau koj daim ntawv thov, qhia meej:
"Internal deg tiav yuav tsum yog 32 Ra siab tshaj plaws, nrog 16 Ra lub hom phiaj rau cov ntu tseem ceeb. Kev ua tiav yuav tsum ntsuas los ntawm profilometry ntawm cov qauv neeg sawv cev los ntawm txhua qhov kawg ntawm txhua lub yeeb nkab. Kev ntsuas huab cua yuav tsum tau ua ntawm 100% ntawm kev tsim khoom los xyuas qhov sib xws."
Kev xaiv Electropolishing:
Rau qhov smoothest nto, xav txog electropolishing tom qab kos duab txias:
Tshem tawm cov haujlwm- tawv txheej txheej.
Ua tiav 4-8 Ra tiav.
Txhim kho corrosion kuj.
Ntxiv cov nqi thiab sijhawm ua haujlwm.
Nto Finish thiab B-2 tus yam ntxwv:
Hastelloy B-2 cov ntsiab lus siab molybdenum:
Ua polishing nyuaj dua stainless hlau.
Yuav tsum tau ua tib zoo lubrication los tiv thaiv galling.
Nws tuaj yeem ua tiav tiav tiav nrog cov cuab yeej tsim nyog.
Verification Protocol:
Kev Xaiv Cov Qauv: Txiav cov qauv los ntawm txhua qhov kawg ntawm cov kav dej sawv cev.
Profilometry: Ntsuas Ra, Rz, thiab Rmax tus nqi.
Acceptance Criteria: Average Ra ≤32, no individual reading >40.
Kev Ntsuas Huab Cua: 100% ntawm cov kav dej hauv ± 5% ntawm tus qauv.
Kev pom zoo:
Rau koj siab - purity tshuaj ua daim ntawv thov, qhia kom txias drawn Hastelloy B-2 kav nrog 16-32 Ra nyob rau hauv nto tiav. Yuav tsum tau ob qho tib si profilometry (ntawm cov qauv) thiab kev ntsuas huab cua (ntawm tag nrho cov kav dej) rau kev txheeb xyuas. Xav txog electropolishing rau cov kev pabcuam tseem ceeb tshaj plaws. Sau tag nrho cov txiaj ntsig rau cov ntaub ntawv zoo.
5. Tshaj tawm -Kev Kho Hniav Kub: Thaum twg yog qhov yuav tsum tau muaj kev ntxhov siab rau cov kav dej Hastelloy B-2, thiab thaum twg yog qhov kev daws teeb meem tag nrho tsim nyog?
Q: Peb tau txias txias Hastelloy B-2 kav dej uas yuav siv rau hauv ib puag ncig corrosive (dilute HCl ntawm ambient kub). Peb tus neeg muag khoom muab "kev ntxhov siab ntxhov siab" ua ib qho kev xaiv ntawm kev kos thiab ua kom tag nrho. Puas yog kev ntxhov siab txaus txaus, lossis peb puas xav tau kev daws teeb meem tag nrho?
A: Qhov kev xaiv ntawm kev daws kev ntxhov siab thiab kev daws teeb meem tag nrho yog nyob ntawm qhov hnyav ntawm qhov chaw corrosive thiab qhov ua haujlwm txias hauv cov yeeb nkab. Rau dilute HCl ntawm ambient kub, kev ntxhov siab yuav txaus, tab sis muaj cov kev xav tseem ceeb.
Nkag siab txog Cov Kev Xaiv:
| Kev kho mob | Kub | Lub hom phiaj | Kev tshwm sim |
|---|---|---|---|
| Raws li - kos | Tsis muaj | Lub zog siab tshaj plaws | Kev ntxhov siab ntau dhau, ua haujlwm- tawv |
| Kev ntxhov siab | 400-500℃(750-930℃F) | Txo cov kev ntxhov siab seem | Kev daws kev ntxhov siab ib nrab, tseem ua haujlwm - tawv |
| Kev daws teeb meem | 1060-1120℃(1940-2050℃F) | Tag nrho recrystallization | Kev ntxhov siab -dawb, mos, siab tshaj corrosion kuj |
Qhov Kev Ruaj Ntseg Ua Li Cas:
Txo cov residual tensile stresses los ntawm 50-70%.
Tsis recrystallize lub grain qauv.
Tsis tshem tawm ua hauj lwm hardening.
Tsis kho corrosion kuj mus rau tag nrho cov qib annealed.
Kev pheej hmoo: Rau B-2, qhov kub ntawm kev ntxhov siab yog nyob rau hauv qhov kev txiav txim ntau (290-455 degree). Qhov no tuaj yeem ua rau cov khoom siv yog tias tsis ua tib zoo tswj.
B-2 Ordering Risk:
Kev ntxhov siab ntawm 400-500℃poob hauv B-2 qhov kev txiav txim ntau. Qhov no txhais tau tias:
Cov khoom tuaj yeem ua nkig thaum lub sij hawm txo kev ntxhov siab.
Ductility tuaj yeem poob ntawm 40% mus rau zero.
Cov yeeb nkab tuaj yeem tawg thaum tuav lossis kev pabcuam tom ntej.
Rau B-2, kev ntxhov siab feem ntau tsis pom zoo vim kev txiav txim siab.
Thaum Solution Annealing yuav tsum tau:
Tag nrho cov tshuaj annealing yuav tsum tau thaum:
Corrosive Ib puag ncig: Txhua qhov kev pheej hmoo corrosion tseem ceeb (xws li dilute HCl).
Vuam Npaj: Yog tias cov kav dej yuav raug welded, HAZ yuav tsum tau muab tshem tawm.
Khoov / sib sau: yog cov kav dej yuav raug tsim ntxiv.
Kev tiv thaiv corrosion siab tshaj plaws: Yuav tsum tau ua kom ntev - kev cia siab rau lub sijhawm.
Kev Pabcuam Tsis Muaj Peev Xwm: Thaum cov xwm txheej yav tom ntej tsis paub.
Thaum Kev Nyuaj Siab Yuav Tau Txais (Tsis tshua muaj):
Kev ntxhov siab tuaj yeem txiav txim siab tsuas yog yog tias:
Kev pabcuam tsis yog-corrosive (piv txwv li, ntsuas cua, roj inert).
Tsis muaj vuam los yog tsim yog npaj.
Kev pabcuam kub tsis tshaj 200 degree.
Qhov kev pheej hmoo ntawm kev txiav txim yog txais thiab sau tseg.
B-3 yuav yog qhov kev xaiv zoo dua rau qhov xwm txheej no.
B-3 Alternative:
Yog tias koj xav tau cov khoom nruab nrab nruab nrab ntawm li - kos thiab tag nrho annealed:
Xav txog B-3 (UNS N10675) hloov B-2.
B-3 tiv taus kev txiav txim.
B-3 tuaj yeem txo qhov kev ntxhov siab yam tsis muaj embrittlement.
B-3 nyob rau hauv cov kev ntxhov siab-relieved tej zaum yuav tau txais rau nruab nrab corrosives.
Kev pom zoo rau koj daim ntawv thov:
Rau dilute HCl ntawm ambient kub:
| Qhov xwm txheej | Kev soj ntsuam |
|---|---|
| Corrosion txaus ntshai | Nruab nrab (dilute HCl) |
| Kub | Ambient (tsis muaj kev txiav txim hauv kev pabcuam) |
| Vuam? | Tsis paub |
| Ntev - kev cia siab rau lub sijhawm | Tseem ceeb |
Kev Txiav Txim Siab: Pom zoo tag nrho cov tshuaj annealing.
Txawm hais tias HCl yog dilute, ib qho kev xeb ntxiv rau qhov seem ntawm kev ntxhov siab ua rau muaj kev pheej hmoo. Qhov kev pheej hmoo ntawm kev txiav txim siab thaum muaj kev ntxhov siab ua rau nws tsis zoo rau B-2. Kev daws annealing muab siab tshaj plaws corrosion kuj thiab tshem tawm kev txiav txim kev txhawj xeeb.
Lus Qhia:
* "Cov kav dej txias Hastelloy B-2 yuav tsum tau txais kev daws teeb meem kawg ntawm 1060-1120℃tom qab los ntawm cov dej nrawm nrawm. Cov khoom siv yuav tsum tau muab rau hauv qhov muag muag muag nrog hardness 95 HRB siab tshaj plaws. Tsis muaj kev tso cai rau kev kho kev ntxhov siab nruab nrab."*
Yog tias Koj Yuav Tsum Siv Kev Nyuaj Siab -Relieved B-2:
Yog tias qhov kev ntxhov siab yog qhov tsim nyog (tsis tshua muaj), ua raws li kev tswj hwm nruj:
Kub: Khaws hauv qab 400℃(750℃F) yog tias ua tau.
Sijhawm: Txo lub sijhawm ntawm qhov kub thiab txias.
Kev Ntsuas: Ua cov kev ntsuas khoov tom qab kho kom paub tseeb tias qhov ductility.
Cov ntaub ntawv: Qhia meej meej txog qhov txaus ntshai.
Kev txheeb xyuas qhov kev kho cua sov kom zoo:
| Kuaj | Kev daws Annealed | Kev ntxhov siab |
|---|---|---|
| Hardness | 85-95 PAB | 25-35 HRC |
| Microstructure | Equiaxed nplej | Deformed nplej |
| Khoov xeem | 180℃OK | Tej zaum tawg |
| Kev kuaj corrosion | Tus nqi qis (<0.5 mm/yr) | Tus nqi siab dua |
Kev pom zoo:
Rau koj qhov kev pab cuam HCl dilute, qhia kom meej tag nrho cov tshuaj annealed Hastelloy B-2 cov kav dej txias. Qhov kev pheej hmoo ntawm kev txiav txim ua rau kev ntxhov siab tsis zoo rau B-2. Yog xav tau cov khoom nruab nrab, xav txog B-3 hloov. Tus nqi me me ntxiv ntawm tag nrho annealing kom ntseeg tau tias kev ua haujlwm ntev ntev.
