Lus Cim Los Ntawm Tus Kws Kho Mob: Pharmaceutical Online zoo siab los nthuav qhia tsab xov xwm plaub ntu no txog kev vuam cov kav dej bioprocess los ntawm tus kws tshaj lij hauv kev lag luam Barbara Henon ntawm Arc Machines. Tsab xov xwm no tau hloov kho los ntawm Dr. Henon cov lus nthuav qhia ntawm lub rooj sib tham ASME thaum kawg ntawm lub xyoo tas los.
Tiv thaiv kom tsis txhob poob qhov kev tiv thaiv xeb. Cov dej ntshiab xws li DI lossis WFI yog cov tshuaj ntxuav xeb rau cov hlau tsis xeb. Tsis tas li ntawd, WFI qib tshuaj raug hloov pauv ntawm qhov kub siab (80 ° C) kom tswj tau qhov tsis muaj kab mob. Muaj qhov sib txawv me ntsis ntawm kev txo qhov kub kom txaus los txhawb cov kab mob uas muaj sia nyob thiab tsa qhov kub kom txaus los txhawb kev tsim "rouge". Rouge yog ib zaj duab xis xim av uas muaj ntau yam sib txawv los ntawm kev xeb ntawm cov khoom siv hauv cov kav dej tsis xeb. Cov av thiab hlau oxides tej zaum yuav yog cov khoom tseem ceeb, tab sis ntau hom hlau, chromium thiab nickel kuj tseem yuav muaj. Qhov muaj rouge ua rau qee yam khoom tuag taus thiab nws qhov muaj nyob yuav ua rau xeb ntxiv, txawm hais tias nws qhov muaj nyob hauv lwm lub cev zoo li tsis muaj teeb meem.
Kev vuam tuaj yeem cuam tshuam tsis zoo rau kev tiv thaiv xeb. Xim kub yog qhov tshwm sim ntawm cov khoom siv oxidizing tso rau ntawm cov vuam thiab HAZs thaum lub sijhawm vuam, tshwj xeeb tshaj yog qhov tsis zoo, thiab cuam tshuam nrog kev tsim cov xim liab hauv cov tshuab dej tshuaj. Kev tsim cov chromium oxide tuaj yeem ua rau muaj xim kub, tawm hauv qab ib txheej chromium-depleted uas yooj yim rau xeb. Xim kub tuaj yeem tshem tawm los ntawm pickling thiab sib tsoo, tshem tawm cov hlau ntawm qhov chaw, suav nrog cov txheej chromium-depleted hauv qab, thiab rov qab kho qhov tsis kam xeb mus rau qib ze rau cov hlau hauv paus. Txawm li cas los xij, pickling thiab sib tsoo yog qhov tsis zoo rau qhov tiav ntawm qhov chaw. Passivation ntawm lub kaw lus kav dej nrog nitric acid lossis chelating agent formulations yog ua los kov yeej cov teebmeem tsis zoo ntawm kev vuam thiab kev tsim ua ntej lub kaw lus kav dej raug muab tso rau hauv kev pabcuam. Auger electron analysis qhia tau hais tias chelation passivation tuaj yeem rov qab hloov pauv ntawm qhov chaw hauv kev faib tawm ntawm oxygen, chromium, hlau, nickel thiab manganese uas tshwm sim hauv thaj chaw vuam thiab thaj chaw cuam tshuam cua sov mus rau lub xeev ua ntej-weld. Txawm li cas los xij, passivation tsuas yog cuam tshuam rau txheej sab nraud thiab tsis nkag mus rau hauv qab 50 angstroms, thaum thermal coloration tuaj yeem ntev 1000 angstroms los yog ntau dua hauv qab nto.
Yog li ntawd, txhawm rau txhim kho cov kav dej uas tiv taus xeb ze rau cov khoom tsis tau vuam, nws yog ib qho tseem ceeb uas yuav tsum sim txwv kev vuam thiab kev puas tsuaj los ntawm kev tsim khoom kom txog rau theem uas tuaj yeem rov qab tau los ntawm kev siv passivation. Qhov no yuav tsum tau siv cov roj purge nrog cov pa oxygen tsawg kawg nkaus thiab xa mus rau sab hauv ntawm qhov sib koom ua ke yam tsis muaj kev ua qias tuaj ntawm cov pa oxygen lossis dej noo. Kev tswj hwm qhov kub thiab kev zam kom raug thaum vuam kuj tseem ceeb heev kom tiv thaiv kev poob ntawm kev tiv thaiv xeb. Kev tswj hwm cov txheej txheem tsim khoom kom ua tiav cov vuam zoo rov ua dua thiab sib xws, nrog rau kev ua tib zoo tuav cov kav dej stainless hlau thiab cov khoom thaum lub sijhawm tsim khoom kom tiv thaiv kev ua qias tuaj, yog qhov yuav tsum tau ua rau cov kav dej zoo uas tiv taus xeb thiab muab kev pabcuam ntev.
Cov ntaub ntawv siv rau hauv cov raj xa dej biopharmaceutical stainless steel uas muaj cov khoom siv siab tau hloov pauv mus rau kev tiv thaiv xeb zoo dua li kaum xyoo dhau los. Feem ntau cov hlau stainless siv ua ntej xyoo 1980 yog 304 stainless steel vim tias nws pheej yig dua thiab zoo dua li tooj liab siv yav dhau los. Qhov tseeb, 300 series stainless steels yooj yim rau kev siv tshuab, tuaj yeem fusion welded yam tsis muaj kev poob ntawm lawv cov kev tiv thaiv xeb, thiab tsis tas yuav tsum tau ua kom sov ua ntej thiab tom qab kub.
Tsis ntev los no, kev siv cov hlau tsis xeb 316 hauv cov kav dej siab tau nce siab. Hom 316 zoo ib yam li Hom 304, tab sis ntxiv rau cov ntsiab lus chromium thiab nickel alloying uas sib xws rau ob qho tib si, 316 muaj li 2% molybdenum, uas txhim kho 316 qhov kev tiv thaiv corrosion. Hom 304L thiab 316L, hu ua "L" qib, muaj cov ntsiab lus carbon qis dua li cov qib txheem (0.035% vs. 0.08%). Qhov kev txo qis ntawm cov ntsiab lus carbon no yog npaj los txo cov carbide precipitation uas yuav tshwm sim vim yog vuam. Qhov no yog kev tsim ntawm chromium carbide, uas ua rau cov ciam teb ntawm cov hlau chromium puag ploj mus, ua rau nws yooj yim rau corrosion. Kev tsim ntawm chromium carbide, hu ua "sensitization," yog lub sijhawm thiab kub nyob ntawm thiab yog teeb meem loj dua thaum tes soldering. Peb tau qhia tias orbital welding ntawm super-austenitic stainless hlau AL-6XN muab ntau corrosion resistant welds dua li cov welds zoo sib xws ua los ntawm tes. Qhov no yog vim orbital welding muab kev tswj hwm meej ntawm amperage, pulsation thiab lub sijhawm, ua rau muaj cua sov qis dua thiab sib npaug dua li kev vuam tes. Kev vuam orbital ua ke nrog "L" qib 304 thiab 316 yuav luag tshem tawm cov carbide precipitation ua ib qho tseem ceeb hauv kev txhim kho xeb hauv cov kav dej.
Kev hloov pauv ntawm qhov kub thiab txias ntawm cov hlau tsis xeb. Txawm hais tias cov txheej txheem vuam thiab lwm yam tuaj yeem khaws cia rau hauv qhov kev kam rau siab heev, tseem muaj qhov sib txawv ntawm qhov kub uas xav tau los vuam cov hlau tsis xeb los ntawm qhov kub thiab txias mus rau qhov kub thiab txias. Tus lej kub yog tus lej ntau yam uas tau muab rau cov hlau tsis xeb tshwj xeeb yaj ntawm lub Hoobkas. Cov tshuaj lom neeg sib xyaw ua ke ntawm txhua pawg tau sau tseg rau ntawm Daim Ntawv Qhia Kev Xeem Hoobkas (MTR) nrog rau kev txheeb xyuas pawg lossis tus lej kub. Hlau ntshiab yaj ntawm 1538 ° C (2800 ° F), thaum cov hlau alloyed yaj hauv ntau qhov kub thiab txias, nyob ntawm hom thiab qhov concentration ntawm txhua alloy lossis cov khoom siv uas muaj. Vim tias tsis muaj ob qhov kub ntawm cov hlau tsis xeb yuav muaj tib qhov concentration ntawm txhua yam khoom, cov yam ntxwv vuam yuav txawv ntawm lub cub tawg mus rau lub cub tawg.
SEM ntawm 316L yeeb nkab orbital welds ntawm AOD yeeb nkab (sab saum toj) thiab EBR khoom (hauv qab) qhia txog qhov sib txawv tseem ceeb hauv qhov du ntawm lub vuam hlaws.
Txawm hais tias ib txoj kev vuam ib zaug xwb yuav ua haujlwm rau feem ntau cov cua sov uas muaj OD thiab phab ntsa tuab zoo sib xws, qee qhov cua sov xav tau amperage tsawg dua thiab qee qhov xav tau amperage siab dua li qub. Vim li no, kev cua sov ntawm cov ntaub ntawv sib txawv ntawm qhov chaw ua haujlwm yuav tsum tau ua tib zoo saib xyuas kom tsis txhob muaj teeb meem. Feem ntau, cua sov tshiab tsuas yog xav tau me ntsis kev hloov pauv hauv amperage kom ua tiav cov txheej txheem vuam zoo.
Teeb meem sulfur. Elemental sulfur yog ib qho impurity cuam tshuam nrog hlau ore uas feem ntau raug tshem tawm thaum lub sijhawm ua cov hlau.AISI Hom 304 thiab 316 stainless hlau tau teev tseg nrog cov ntsiab lus sulfur siab tshaj plaws ntawm 0.030%. Nrog rau kev txhim kho ntawm cov txheej txheem refining steel niaj hnub, xws li Argon Oxygen Decarburization (AOD) thiab dual vacuum melting practices xws li Vacuum Induction Melting ua raws li Vacuum Arc Remelting (VIM + VAR), nws tau ua tau los tsim cov hlau uas tshwj xeeb heev hauv cov hauv qab no. lawv cov tshuaj lom neeg. Nws tau raug sau tseg tias cov khoom ntawm lub pas dej weld hloov pauv thaum cov ntsiab lus sulfur ntawm cov hlau qis dua li 0.008%. Qhov no yog vim muaj cov nyhuv ntawm sulfur thiab rau qee qhov tsawg dua lwm yam ntsiab lus ntawm qhov kub thiab txias coefficient ntawm qhov nro ntawm lub pas dej weld, uas txiav txim siab cov yam ntxwv ntws ntawm lub pas dej kua.
Thaum muaj cov sulfur concentration tsawg heev (0.001% – 0.003%), qhov nkag mus ntawm qhov weld puddle yuav dav heev piv rau cov welds zoo sib xws ua rau ntawm cov ntaub ntawv nruab nrab sulfur. Cov welds ua rau ntawm cov yeeb nkab stainless hlau sulfur tsawg yuav muaj cov welds dav dua, thaum ntawm cov yeeb nkab phab ntsa tuab dua (0.065 nti, lossis 1.66 hli lossis ntau dua) yuav muaj qhov nyiam ua rau cov welds Recess welding. Thaum lub sijhawm vuam txaus los tsim cov vuam nkag mus tag nrho. Qhov no ua rau cov ntaub ntawv uas muaj cov sulfur concentration tsawg heev nyuaj rau vuam, tshwj xeeb tshaj yog nrog cov phab ntsa tuab dua. Ntawm qhov kawg siab dua ntawm cov sulfur concentration hauv 304 lossis 316 stainless hlau, lub hlaws weld feem ntau yuav tsis muaj kua hauv qhov tsos thiab ntxhib dua li cov ntaub ntawv sulfur nruab nrab. Yog li ntawd, rau weldability, cov sulfur concentration zoo tagnrho yuav nyob rau hauv qhov ntau ntawm kwv yees li 0.005% txog 0.017%, raws li tau teev tseg hauv ASTM A270 S2 rau cov yeeb nkab zoo tshuaj.
Cov neeg tsim cov yeeb nkab stainless hlau electropolished tau pom tias txawm tias cov sulfur theem nrab hauv 316 lossis 316L stainless hlau ua rau nws nyuaj rau ua kom tau raws li qhov xav tau ntawm lawv cov neeg siv khoom semiconductor thiab biopharmaceutical rau cov nplaim du, tsis muaj qhov. Kev siv scanning electron microscopy los xyuas qhov du ntawm lub raj nplaim tiav yog qhov tshwm sim ntau dua. Sulfur hauv cov hlau puag tau pom tias tsim cov khoom tsis yog hlau lossis manganese sulfide (MnS) "stringers" uas raug tshem tawm thaum lub sijhawm electropolishing thiab tawm hauv qhov khoob hauv 0.25-1.0 micron ntau yam.
Cov chaw tsim khoom thiab cov neeg muag khoom ntawm cov raj electropolished tab tom tsav tsheb mus rau kev siv cov khoom siv ultra-low sulfur kom tau raws li lawv cov kev xav tau tiav ntawm qhov chaw. Txawm li cas los xij, qhov teeb meem tsis yog txwv rau cov raj electropolished, vim tias hauv cov raj tsis electropolished cov khoom suav nrog raug tshem tawm thaum lub sijhawm passivation ntawm lub kaw lus piping. Cov voids tau pom tias yuav yooj yim rau pitting dua li thaj chaw du. Yog li muaj qee qhov laj thawj tsim nyog rau qhov sib txawv ntawm cov khoom siv qis-sulfur, "huv dua".
Arc deflection. Ntxiv rau kev txhim kho qhov weldability ntawm stainless hlau, qhov muaj qee cov sulfur kuj txhim kho kev siv tshuab. Yog li ntawd, cov chaw tsim khoom thiab cov chaw tsim khoom feem ntau xaiv cov khoom siv ntawm qhov kawg siab dua ntawm cov ntsiab lus sulfur teev tseg. Kev vuam cov kav dej nrog cov sulfur concentration qis heev rau cov khoom siv, cov li qub lossis lwm cov kav dej nrog cov ntsiab lus sulfur ntau dua tuaj yeem tsim teeb meem vuam vim tias arc yuav raug cuam tshuam rau cov kav dej nrog cov ntsiab lus sulfur tsawg. Thaum arc deflection tshwm sim, qhov nkag mus tob dua ntawm sab qis-sulfur dua li ntawm sab siab-sulfur, uas yog qhov sib txawv ntawm qhov tshwm sim thaum vuam cov kav dej nrog cov ntsiab lus sulfur sib phim. Hauv cov xwm txheej hnyav, lub hlaws weld tuaj yeem nkag mus rau cov khoom siv qis-sulfur thiab tawm hauv sab hauv ntawm qhov weld tsis tau fused kiag li (Fihey thiab Simeneau, 1982). Txhawm rau kom phim cov ntsiab lus sulfur ntawm cov khoom siv rau cov ntsiab lus sulfur ntawm cov yeeb nkab, Carpenter Steel Division ntawm Car-penter Technology Corporation ntawm Pennsylvania tau qhia txog cov sulfur qis (0.005% max) 316 bar Tshuag (Hom 316L-SCQ) (VIM + VAR)) rau kev tsim cov khoom siv thiab lwm yam khoom uas xav tau vuam rau cov kav dej uas muaj sulfur tsawg. Kev vuam ob yam khoom uas muaj sulfur tsawg heev rau ib leeg yooj yim dua li kev vuam cov khoom uas muaj sulfur tsawg heev rau ib yam uas muaj sulfur ntau dua.
Qhov kev hloov mus rau kev siv cov raj xa dej uas muaj cov leej faj tsawg feem ntau yog vim qhov xav tau kom tau txais cov nplaim sab hauv uas muaj electropolished du. Thaum qhov tiav ntawm qhov chaw thiab electropolishing yog qhov tseem ceeb rau ob qho tib si kev lag luam semiconductor thiab kev lag luam biotech / tshuaj, SEMI, thaum sau cov lus qhia txog kev lag luam semiconductor, tau teev tseg tias 316L tubing rau cov kab roj ua haujlwm yuav tsum muaj 0.004% sulfur cap rau kev ua haujlwm zoo tshaj plaws. Qhov kawg ntawm qhov chaw. ASTM, ntawm qhov tod tes, hloov kho lawv cov lus qhia ASTM 270 kom suav nrog cov raj xa dej qib tshuaj uas txwv cov ntsiab lus sulfur rau ntau yam ntawm 0.005 txog 0.017%. Qhov no yuav tsum ua rau muaj teeb meem vuam tsawg dua piv rau cov sulfurs qis dua. Txawm li cas los xij, nws yuav tsum tau sau tseg tias txawm tias nyob hauv qhov txwv no, arc deflection tseem yuav tshwm sim thaum vuam cov kav dej uas muaj sulfur tsawg rau cov kav dej lossis cov khoom siv uas muaj sulfur ntau, thiab cov neeg teeb tsa yuav tsum ua tib zoo saib xyuas qhov cua sov ntawm cov khoom siv thiab xyuas ua ntej tsim khoom. Kev sib raug zoo ntawm solder ntawm cua sov. Kev tsim cov welds.
lwm cov ntsiab lus tsis tshua muaj. Cov ntsiab lus tsis tshua muaj xws li sulfur, oxygen, txhuas, silicon thiab manganese tau pom tias cuam tshuam rau kev nkag mus. Cov txhuas, silicon, calcium, titanium thiab chromium me me uas muaj nyob rau hauv cov hlau puag raws li cov oxide inclusions yog txuam nrog kev tsim slag thaum lub sijhawm vuam.
Cov teebmeem ntawm ntau yam ntsiab lus yog sib sau ua ke, yog li qhov muaj oxygen tuaj yeem them rov qab qee qhov teebmeem sulfur qis. Cov txhuas ntau tuaj yeem tiv thaiv qhov cuam tshuam zoo rau kev nkag mus ntawm sulfur. Manganese volatilizes ntawm qhov kub vuam thiab cov khoom tso rau hauv thaj chaw vuam cua sov. Cov khoom tso manganese no cuam tshuam nrog kev poob ntawm kev tiv thaiv corrosion. (Saib Cohen, 1997). Kev lag luam semiconductor tam sim no tab tom sim nrog cov khoom siv manganese qis thiab txawm tias cov khoom siv manganese 316L qis heev los tiv thaiv qhov poob ntawm kev tiv thaiv corrosion.
Kev tsim cov slag. Qee zaum cov kob slag tshwm sim ntawm cov hlau stainless hlau rau qee qhov kub. Qhov no yog qhov teeb meem ntawm cov khoom siv, tab sis qee zaum kev hloov pauv ntawm cov txheej txheem vuam tuaj yeem txo qhov no, lossis kev hloov pauv ntawm argon / hydrogen sib xyaw tuaj yeem txhim kho qhov vuam. Pollard pom tias qhov sib piv ntawm txhuas rau silicon hauv cov hlau puag cuam tshuam rau kev tsim slag. Txhawm rau tiv thaiv kev tsim cov plaque-type slag tsis xav tau, nws pom zoo kom khaws cov ntsiab lus txhuas ntawm 0.010% thiab cov ntsiab lus silicon ntawm 0.5%. Txawm li cas los xij, thaum Al / Si piv siab dua qib no, slag spherical yuav tsim es tsis yog hom plaque. Hom slag no tuaj yeem tawm hauv qhov tom qab electropolishing, uas tsis lees txais rau cov ntawv thov purity siab. Cov kob slag uas tsim ntawm OD ntawm qhov vuam tuaj yeem ua rau nkag mus tsis sib xws ntawm ID pass thiab tuaj yeem ua rau tsis txaus nkag mus. Cov kob slag uas tsim ntawm ID weld bead tej zaum yuav raug xeb.
Kev vuam ib zaug nrog kev sib hloov. Kev vuam raj orbital tsis siv neeg yog kev vuam ib zaug nrog kev hloov pauv tam sim no thiab kev sib hloov ceev tas mus li. Cov txheej txheem no haum rau cov yeeb nkab nrog sab nraud txoj kab uas hla ntawm 1/8″ txog kwv yees li 7″ thiab phab ntsa tuab ntawm 0.083″ thiab hauv qab. Tom qab lub sijhawm ua ntej-purge, arcing tshwm sim. Kev nkag mus rau ntawm phab ntsa raj yog ua tiav thaum lub sijhawm ncua sijhawm uas arcing muaj tab sis tsis muaj kev sib hloov tshwm sim. Tom qab qhov kev ncua sijhawm tig no, lub electrode tig ib ncig ntawm qhov sib koom ua ke kom txog thaum qhov sib koom ua ke lossis sib tshooj thawj qhov ntawm qhov sib koom ua ke thaum lub sijhawm kawg ntawm kev vuam. Thaum kev sib txuas tiav, tam sim no tapers tawm hauv lub sijhawm poob.
Hom kauj ruam ("synchronized" vuam). Rau kev sib xyaw vuam ntawm cov ntaub ntawv phab ntsa tuab dua, feem ntau loj dua 0.083 nti, lub zog vuam sib xyaw tuaj yeem siv rau hauv hom synchronous lossis kauj ruam. Hauv hom synchronous lossis kauj ruam, lub zog vuam tam sim no yog synchronized nrog lub stroke, yog li lub rotor yog stationary rau qhov nkag mus rau qhov siab tshaj plaws thaum lub sijhawm siab tam sim no pulses thiab txav mus thaum lub sijhawm qis tam sim no pulses. Cov txheej txheem synchronous siv lub sijhawm ntev dua, ntawm qhov kev txiav txim ntawm 0.5 txog 1.5 vib nas this, piv rau kaum lossis ib puas ntawm lub sijhawm pulse thib ob rau kev vuam ib txwm muaj. Cov txheej txheem no tuaj yeem vuam 0.154 ″ lossis 6 ″ tuab 40 gauge 40 phab ntsa nyias nrog 0.154 ″ lossis 6 ″ phab ntsa tuab. Cov txheej txheem stepped tsim cov vuam dav dua, ua rau nws ua txhaum tsis kam thiab pab tau rau kev vuam cov khoom tsis xwm yeem xws li cov yeeb nkab fittings rau cov yeeb nkab qhov twg yuav muaj qhov sib txawv hauv kev kam rau siab, qee qhov tsis sib xws lossis Cov Khoom Siv thermal tsis sib xws. Hom kev vuam no xav tau kwv yees li ob npaug ntawm lub sijhawm arc ntawm kev vuam ib txwm muaj thiab tsis haum rau ultra-high-purity (UHP) daim ntawv thov vim yog dav dua, ntxhib dua.
Cov hloov pauv programmable. Lub sijhawm tam sim no ntawm cov fais fab vuam yog microprocessor-based thiab khaws cov kev pab cuam uas teev cov nqi lej rau cov kev ntsuas vuam rau ib txoj kab uas hla tshwj xeeb (OD) thiab phab ntsa tuab ntawm cov yeeb nkab kom raug welded, suav nrog lub sijhawm purge, tam sim no vuam, qhov ceev mus ncig (RPM)), tus lej ntawm cov txheej thiab lub sijhawm ib txheej, lub sijhawm pulse, lub sijhawm downhill, thiab lwm yam. Rau cov yeeb nkab orbital welds nrog cov hlau filler ntxiv, cov kev ntsuas program yuav suav nrog qhov ceev pub hlau, lub teeb oscillation amplitude thiab lub sijhawm nyob, AVC (arc voltage tswj kom muab qhov sib txawv arc tas li), thiab upslope. Txhawm rau ua fusion welding, nruab lub taub hau vuam nrog cov electrode thiab cov yeeb nkab clamp ntxig rau ntawm cov yeeb nkab thiab rov qab nco lub sijhawm vuam lossis kev pab cuam los ntawm lub cim xeeb fais fab. Cov txheej txheem vuam yog pib los ntawm kev nias lub pob lossis lub vaj huam sib luag membrane thiab kev vuam txuas ntxiv yam tsis muaj kev cuam tshuam ntawm tus neeg teb xov tooj.
Cov hloov pauv uas tsis yog programmable. Yuav kom tau txais qhov zoo ntawm kev vuam, cov kev ntsuas vuam yuav tsum tau tswj hwm kom zoo. Qhov no ua tiav los ntawm qhov tseeb ntawm lub zog vuam thiab qhov kev pab cuam vuam, uas yog cov lus qhia nkag mus rau hauv lub zog, muaj cov kev ntsuas vuam, rau kev vuam ib qho loj me ntawm cov yeeb nkab lossis yeeb nkab. Kuj tseem yuav tsum muaj cov qauv vuam zoo, qhia txog cov qauv lees txais vuam thiab qee qhov kev tshuaj xyuas vuam thiab kev tswj hwm zoo kom ntseeg tau tias kev vuam ua tau raws li cov qauv pom zoo. Txawm li cas los xij, qee yam thiab cov txheej txheem tsis yog cov kev ntsuas vuam kuj yuav tsum tau tswj hwm kom zoo. Cov yam no suav nrog kev siv cov khoom siv npaj kawg zoo, kev ntxuav thiab kev coj ua zoo, kev kam rau siab zoo ntawm cov yeeb nkab lossis lwm qhov chaw raug vuam, hom tungsten thiab qhov loj me sib xws, cov pa roj inert huv si, thiab kev saib xyuas zoo rau cov khoom siv hloov pauv.- kub siab.
Cov kev cai npaj rau kev vuam kawg ntawm cov yeeb nkab yog qhov tseem ceeb dua rau kev vuam orbital dua li kev vuam tes. Cov pob qij txha vuam rau kev vuam yeeb nkab orbital feem ntau yog cov pob qij txha square. Txhawm rau kom ua tiav qhov rov ua dua xav tau hauv kev vuam orbital, kev npaj kawg kom meej, sib xws, thiab machined yog qhov yuav tsum tau ua. Vim tias qhov hluav taws xob vuam nyob ntawm phab ntsa tuab, cov kawg yuav tsum yog square tsis muaj burrs lossis bevels ntawm OD lossis ID (OD lossis ID), uas yuav ua rau phab ntsa tuab sib txawv.
Cov kav dej kawg yuav tsum haum ua ke hauv lub taub hau vuam kom tsis muaj qhov sib txawv ntawm qhov kawg ntawm lub pob qij txha plaub fab. Txawm hais tias cov pob qij txha vuam nrog cov qhov sib txawv me me tuaj yeem ua tiav, qhov zoo ntawm vuam yuav raug cuam tshuam tsis zoo. Qhov sib txawv loj dua, qhov yuav muaj teeb meem ntau dua. Kev sib dhos tsis zoo tuaj yeem ua rau kev vuam tsis ua haujlwm tag nrho. Cov tshuab txiav yeeb nkab ua los ntawm George Fischer thiab lwm tus uas txiav cov yeeb nkab thiab ntsib cov yeeb nkab kawg hauv tib qho kev ua haujlwm, lossis cov tshuab npaj kawg zoo li cov uas ua los ntawm Protem, Wachs, thiab lwm tus, feem ntau siv los ua cov vuam orbital du uas tsim nyog rau kev ua haujlwm. Cov tshuab txiav chop, hacksaws, cov tshuab txiav band thiab cov tshuab txiav tubing tsis haum rau lub hom phiaj no.
Ntxiv rau cov kev ntsuas vuam uas muab lub zog rau vuam, muaj lwm yam uas tuaj yeem muaj kev cuam tshuam loj heev rau kev vuam, tab sis lawv tsis yog ib feem ntawm cov txheej txheem vuam tiag tiag. Qhov no suav nrog hom thiab qhov loj ntawm tungsten, hom thiab qhov huv ntawm cov roj siv los tiv thaiv lub arc thiab ntxuav sab hauv ntawm qhov sib koom ua ke vuam, qhov nrawm ntawm cov roj siv rau kev ntxuav, hom lub taub hau thiab qhov chaw siv hluav taws xob, kev teeb tsa ntawm qhov sib koom ua ke, thiab lwm yam ntaub ntawv tseem ceeb. Peb hu cov hloov pauv no "tsis-programmable" thiab sau lawv rau ntawm daim ntawv teev sijhawm vuam. Piv txwv li, hom roj raug suav hais tias yog qhov hloov pauv tseem ceeb hauv Welding Procedure Specification (WPS) rau cov txheej txheem vuam kom ua raws li ASME Seem IX Boiler thiab Pressure Vessel Code. Kev hloov pauv hauv hom roj lossis feem pua ​​​​​​ntawm cov roj sib xyaw, lossis tshem tawm ntawm ID purging yuav tsum tau rov ua dua ntawm cov txheej txheem vuam.
Cov roj vuam. Cov hlau tsis xeb tsis yooj yim rau cov pa oxygen oxidation hauv chav tsev kub. Thaum nws raug cua sov mus rau nws qhov chaw yaj (1530 ° C lossis 2800 ° F rau cov hlau ntshiab) nws yooj yim oxidized. Inert argon feem ntau yog siv ua cov roj tiv thaiv thiab rau kev ntxuav cov pob qij txha sab hauv los ntawm cov txheej txheem GTAW orbital. Qhov huv ntawm cov roj piv rau oxygen thiab noo noo txiav txim siab qhov ntau ntawm oxidation-induced discoloration uas tshwm sim ntawm lossis ze ntawm qhov vuam tom qab vuam. Yog tias cov roj purge tsis zoo tshaj plaws lossis yog tias lub kaw lus purge tsis tau xau tag nrho xws li me me ntawm cov cua xau rau hauv lub kaw lus purge, qhov oxidation yuav yog lub teeb teal lossis bluish. Tau kawg, tsis muaj kev ntxuav yuav ua rau qhov chaw dub crusty feem ntau hu ua "qab zib". Cov qib vuam argon muab rau hauv lub tog raj kheej yog 99.996-99.997% ntshiab, nyob ntawm tus neeg muag khoom, thiab muaj 5-7 ppm ntawm oxygen thiab lwm yam impurities, suav nrog H2O, O2, CO2, hydrocarbons, thiab lwm yam, rau tag nrho ntawm 40 ppm siab tshaj plaws. Cov argon uas muaj purity siab hauv lub tog raj kheej lossis cov argon kua hauv Dewar tuaj yeem yog 99.999% ntshiab lossis 10 ppm tag nrho cov khoom tsis huv, nrog rau siab tshaj plaws ntawm 2 ppm oxygen. CEEB TOOM: Cov tshuab lim roj xws li Nanochem lossis Gatekeeper tuaj yeem siv thaum lub sijhawm purging kom txo cov qib kev ua qias tuaj rau qhov feem ib billion (ppb) ntau yam.
sib xyaw ua ke. Cov roj sib xyaw xws li 75% helium/25% argon thiab 95% argon/5% hydrogen siv tau ua cov pa roj tiv thaiv rau cov kev siv tshwj xeeb. Ob qho kev sib xyaw ua ke no tsim cov vuam kub dua li cov uas ua nyob rau hauv tib qho chaw teeb tsa program li argon. Cov Helium sib xyaw yog qhov tsim nyog tshwj xeeb rau kev nkag mus ntau tshaj plaws los ntawm kev vuam fusion ntawm cov hlau carbon. Tus kws pab tswv yim kev lag luam semiconductor txhawb nqa kev siv cov argon/hydrogen sib xyaw ua cov pa roj tiv thaiv rau cov kev siv UHP. Cov hydrogen sib xyaw muaj ntau qhov zoo, tab sis kuj muaj qee qhov tsis zoo loj. Qhov zoo yog tias nws tsim cov dej ntub dua thiab qhov chaw vuam du dua, uas yog qhov zoo tagnrho rau kev siv cov txheej txheem xa roj siab heev nrog qhov chaw du li sai tau. Qhov muaj hydrogen muab cov huab cua txo qis, yog li ntawd yog tias muaj cov pa oxygen nyob rau hauv cov roj sib xyaw, qhov vuam uas tshwm sim yuav zoo li huv dua nrog cov xim tsawg dua li cov pa oxygen zoo sib xws hauv argon ntshiab. Cov nyhuv no zoo tshaj plaws ntawm kwv yees li 5% hydrogen. Qee tus siv 95/5% argon/hydrogen sib xyaw ua ID purge los txhim kho qhov zoo li ntawm lub hlaws vuam sab hauv.
Lub vuam siv cov hydrogen sib xyaw ua cov roj tiv thaiv yog nqaim dua, tsuas yog tias cov hlau tsis xeb muaj cov sulfur tsawg heev thiab tsim cov cua sov ntau dua hauv qhov vuam dua li qhov chaw tam sim no nrog argon tsis sib xyaw. Ib qho tsis zoo ntawm cov argon/hydrogen sib xyaw yog tias lub arc tsis ruaj khov dua li argon ntshiab, thiab muaj qhov nyiam rau lub arc kom txav mus los, hnyav txaus kom ua rau tsis sib haum. Arc txav mus los yuav ploj mus thaum siv cov roj sib xyaw sib txawv, qhia tias nws yuav yog los ntawm kev ua qias tuaj lossis kev sib xyaw tsis zoo. Vim tias cov cua sov tsim los ntawm lub arc sib txawv nrog qhov concentration hydrogen, qhov concentration tas li yog qhov tseem ceeb kom ua tiav cov welds rov ua dua, thiab muaj qhov sib txawv ntawm cov roj fwj ua ntej sib xyaw. Lwm qhov tsis zoo yog tias lub neej ntawm tungsten luv dua thaum siv cov hydrogen sib xyaw. Txawm hais tias qhov laj thawj rau kev puas tsuaj ntawm tungsten los ntawm cov roj sib xyaw tsis tau txiav txim siab, nws tau tshaj tawm tias lub arc nyuaj dua thiab tungsten yuav tsum tau hloov tom qab ib lossis ob qhov welds. Argon/hydrogen sib xyaw tsis tuaj yeem siv los vuam cov hlau carbon lossis titanium.
Ib qho tshwj xeeb ntawm cov txheej txheem TIG yog tias nws tsis siv cov electrodes. Tungsten muaj qhov chaw yaj siab tshaj plaws ntawm txhua yam hlau (6098 ° F; 3370 ° C) thiab yog lub tshuab hluav taws xob zoo, ua rau nws tsim nyog siv ua lub electrode uas tsis siv tau. Nws cov khoom tau txhim kho los ntawm kev ntxiv 2% ntawm qee cov oxides av tsis tshua muaj xws li ceria, lanthanum oxide lossis thorium oxide los txhim kho arc pib thiab arc stability. Tungsten ntshiab tsis tshua siv hauv GTAW vim yog cov khoom zoo dua ntawm cerium tungsten, tshwj xeeb tshaj yog rau cov ntawv thov GTAW orbital. Thorium tungsten siv tsawg dua li yav dhau los vim tias lawv muaj qee yam radioactive.
Cov electrodes uas muaj qhov tiav polished muaj qhov loj sib npaug ntau dua. Ib qho chaw du yeej ib txwm zoo dua li qhov chaw ntxhib lossis tsis sib xws, vim tias qhov sib xws ntawm electrode geometry yog qhov tseem ceeb rau kev sib xws, sib xws, thiab cov txiaj ntsig vuam. Cov electrons tawm ntawm lub taub hau (DCEN) hloov cua sov los ntawm lub taub hau tungsten mus rau qhov vuam. Lub taub hau me dua tso cai rau qhov ceev tam sim no kom khaws cia siab heev, tab sis yuav ua rau lub neej tungsten luv dua. Rau kev vuam orbital, nws yog ib qho tseem ceeb uas yuav tsum tau sib tsoo lub taub hau electrode kom ntseeg tau tias qhov rov ua dua ntawm tungsten geometry thiab qhov rov ua dua ntawm qhov vuam. Lub taub hau blunt yuam lub arc los ntawm qhov vuam mus rau tib qho chaw ntawm tungsten. Lub taub hau txoj kab uas hla tswj cov duab ntawm lub arc thiab qhov ntau ntawm kev nkag mus ntawm qhov tam sim no tshwj xeeb. Lub kaum sab xis taper cuam tshuam rau cov yam ntxwv tam sim no / voltage ntawm lub arc thiab yuav tsum tau teev tseg thiab tswj hwm. Qhov ntev ntawm tungsten yog qhov tseem ceeb vim tias qhov ntev paub ntawm tungsten tuaj yeem siv los teeb tsa qhov sib txawv arc. Qhov sib txawv arc rau tus nqi tam sim no tshwj xeeb txiav txim siab qhov voltage thiab yog li lub zog siv rau qhov vuam.
Qhov loj ntawm electrode thiab nws txoj kab uas hla ntawm lub taub hau raug xaiv raws li qhov muaj zog ntawm qhov vuam tam sim no. Yog tias qhov tam sim no siab dhau rau lub electrode lossis nws lub taub hau, nws yuav poob hlau ntawm lub taub hau, thiab siv cov electrodes nrog txoj kab uas hla ntawm lub taub hau uas loj dhau rau qhov tam sim no yuav ua rau arc drift. Peb qhia cov electrode thiab txoj kab uas hla ntawm lub taub hau los ntawm phab ntsa tuab ntawm qhov sib koom ua ke thiab siv 0.0625 txoj kab uas hla rau yuav luag txhua yam txog li 0.093″ phab ntsa tuab, tshwj tsis yog tias kev siv yog tsim los siv nrog 0.040″ txoj kab uas hla electrodes rau kev vuam cov khoom me me precision. Rau qhov rov ua dua ntawm cov txheej txheem vuam, tungsten hom thiab tiav, ntev, taper kaum sab xis, txoj kab uas hla, txoj kab uas hla ntawm lub taub hau thiab arc gap yuav tsum tau teev tseg thiab tswj hwm. Rau cov ntawv thov vuam raj, cerium tungsten ib txwm pom zoo vim tias hom no muaj lub neej ua haujlwm ntev dua li lwm hom thiab muaj cov yam ntxwv zoo heev arc ignition. Cerium tungsten tsis yog radioactive.
Yog xav paub ntxiv, thov hu rau Barbara Henon, Tus Thawj Saib Xyuas Kev Tshaj Tawm Txog Kev Siv Tshuab, Arc Machines, Inc., 10280 Glenoaks Blvd., Pacoima, CA 91331. Xov tooj: 818-896-9556. Fax: 818-890-3724.