ASTM A240 317 1.4449 2B Ua tiav cov ntawv stainless hlau 321 316L ntawv- Phaj SS 304 kauj 304L

Qeb 304 \ / 304l (tsis yog s30400 \ / s30403, en 1.4301 \ feem ntau dav siv Antensi Stainless hlau. Nws suav rau ntau tshaj 50% ntawm txhua qhov stainless hlau tsim, sawv cev ntawm 50% - 60% ntawm kev siv ntawm stainless cov ntaub ntawv thiab fin cov ntawv thov nyob rau hauv yuav luag txhua kev lag luam.

A182 321 stainless hlau flange yog ib hom flange tau los ntawm cov hlau zoo stainless uas yog feem ntau siv hauv kev siv cov ntawv thov. ASTM A182 321 Flange tseem hu ua tus hlau 321 flange thiab yog tsim los txuas ob cov kav dej ua ke nyob rau hauv kev nyab xeeb thiab xau yam.

Coils, ntawv ci, yob cov ntawv dawb, shim ntawv, phaj perforated, sawb, dawb paug (flange) thiab lwm yam.

Peb Aluminoy Hlau A234 WP9 Yeeb Nkab Luj Tshib Muaj nyob rau hauv ib tug xov tooj ntawm cov phab ntsa WP9

Stainless hlau yog ib qho ntawm cov khoom nrov tshaj plaws hauv kev tsim khoom lag luam. Qhov no ua rau dabtsi yog khoov stainless hlau tubing yog tus qauv tsim cov txheej txheem rau kev tsim cov hlau rau ntau yam kev siv. Cov kws ua choj thiab cov tsim qauv xav txog nws tus thawj xibfwb kev ua haujlwm ua ib feem ntawm lub kaw lus tubing thiab piping.

Nws ua rau pom zoo tsis kam mus rau nruab nrab thiab txo qhov chaw. Cov alloy no tsim ib zaj yeeb yaj kiab oxide, kev tiv thaiv zaj duab xis uas tsis tawm mus, tab sis nws khaws cov oxidation superi-sauv tsis kub.

Inconel 718 yog npib tsib xee-chromium-based alloy uas feem ntau siv nyob rau hauv cov ntawv thov kub siab xws li aerospace thiab roj turbines. Ib qho ntawm cov tseem ceeb tshaj plaws hauv kev tsim cov astm b670 inconel 718 daim ntawv yog lub phaj dov. Muaj ob hom tseem ceeb ntawm inconel 718 daim hlau muaj nyob rau ntawm kev ua lag luam: kub dov thiab cov phiaj txias. Cov paib.

HT 45 Degree Luj tshib 10 x90 12.70mm carbon steel seamless A234 WP9 1189458
Hastelloy C2000 tub tshij yog siv nyob rau hauv ntau hom petrochemical suav nrog cov khoom siv tshuaj lom neeg, roj kev tsim khoom siv, roj ntxiv thiab cov nroj tsuag hluav taws xob.
ASTM A335 P5, P9, P11, P12, P22, P91, P141

Incoloy 800H Flange Peb muaj lub koob npe nrov hauv kev lag luam rau kev tsim cov hom kev ua haujlwm zoo ntawm cov hom uas yuav tsum tau ua rau peb cov neeg siv khoom. Peb tsim khoom tsim prololoy 800 flanges uas muaj kev ntseeg siab thiab siab dua. Peb siv cov peev txheej hwm thiab qib siab tshaj tawm rau kev tsim ASTM B564 UNFANCES 800 flanges.

Qhov ntxiv titanium, nrog kev kho cua sov kom raug, ruaj khov qhov ntxim nyiam ntawm inconel phaj flanges rau intergranular corrosion. Nrog kev cog lus tsis txaus ntseeg los ua kom zoo, peb muab rau peb cov neeg siv khoom muaj ntau yam ntawm lub ntsej muag weld tig ntsej muag.

Inconel 625 coil yog cov yam ntxwv zoo los ntawm nws cov kev tiv thaiv zoo rau oxidation, qhov siab-kub corrosion thiab qaug zog. ASTM B443 tsis yog N06625 Inconel P phaj tau siv dav hauv Aerospace, kev ua lag luam thiab roj thiab muaj zog zoo dua qub txawm tias muaj ib puag ncig zoo.

Thaum nce qhov kub thiab txias lub anealed thiab tov annealed alloy qhia zoo tsis kam rau scaling thiab muaj lub zog siab. Lub alloy kuj tseem AMGONIA cov kabmob cov kabmob, nrog rau cov roj ntsha nitrogen thiab carburizing.

Muaj cov qauv sib txawv los npog qhov sib txawv ntawm cov flanges. Ansi B16.5 Monel Din 2.4360 Qhov muag tsis pom Flange uas muaj diameters los ntawm? nti rau 48 ntiv taw hauv cov qauv no.

N08825 swb hauv qab-rau Flange Incoloy 825 Flanges (UNLANGES (tooj liab, tooj liab, thiab titanium rau hauv nws cov npib tsib xee-chromium puag. Cov hlau ntxiv muab Incoloy 825 Dig Muag Flange Excellance Kuj tiv thaiv corrosion, ntau dua li lwm cov nickel alloys.

Caw 36 ® yog npib npib npib tsib xee, tsis muaj nyiaj npib ob leeg uas muaj 36%, commar 36 muaj qhov kub tsawg los ntawm kev nthuav dav ntawm + 500 ° F (260 ° C).

Alloy 800 yog npib npib tsib xee-chromium alloy nrog siab zog thiab kev tiv thaiv zoo rau oxidation thiab corrosion ntawm qhov kub. ASTM B407 UNICS NC08800 INCOLOY 800 W. NR. 1.4876 Welded yeeb nkab yog dav siv rau kev tsim kho cov khoom siv uas yuav tsum tau ua rau corrosion tsis kam, lub zog, thiab ruaj khov rau kev pabcuam txog 1500 ° F (816 ° C).

Nickel Alloy tuav & RDS
DupleX Steel Flanges
Titanium lub ntom yog li 60% uas ntawm stainless hlau thiab nickel alloys, qhov hnyav no txuag ua rau nws xaiv qhov chaw zoo uas yog qhov tseem ceeb xws li aerospace.
Rau mating sealing nrog cov iav nyuaj

ASTM A403 W316 yog tus qauv molybdenum-bearing qib, thib ob hauv qhov tseem ceeb txog 304 nyob rau hauv kev ua kom tsis muaj cua sov. Lub Molybdenum muab 316 zoo dua thoob plaws lub zog tiv thaiv ntau dua qib 304, tshwj xeeb tshaj yog ntau dua rau pitting thiab crevice corrosion hauv chloride ib puag ncig.

Yog tsis muaj kev sib nqus nyob rau hauv anealed mob, tab sis tuaj yeem ua me ntsis sib nqus los ntawm kev ua haujlwm txias lossis siv vuam. 304 SS daim ntawv tuaj yeem muab tau yooj yim thiab ua tiav los ntawm kev coj ua fabrication.
ASME Attm Din Jis Aisi Stainless Hlau Forging Flange

ASME B36.19M yog tus qauv kev qhia tshwj xeeb rau cov kav hlau stainless hlau, uas qhia txog kev ua siab ntev, thiab tsim khoom rau cov kav dej thiab cov txiv ntseej.

Lub corrosion resistant Hastelloy alloys tau siv dav los ntawm kev lag luam ua lag luam. Qhov kev xav tau rau kev ua tau zoo ua rau lawv txoj kev lees paub thiab kev loj hlob hauv thaj chaw ntawm lub zog, kev noj qab haus huv thiab ib puag ncig, roj thiab cov roj thiab cov roj cuv khw desulfurization.

Raws li cov alloy zoo heev, cov corrosion tsis kam ntawm tooj liab-tsibckel 70 \ tubing ua rau nws muaj txiaj ntsig ntxiv rau kev lag luam uas yuav tsum corrosion tsis kam.

Nickel-Tooj-based alloy 400 monel 2.4360 txias kos cov kab mob kev ntxhov siab thaum raug rau corrosive cracking thaum raug rau cov media corrosive nyob rau hauv ib puag ncig ib puag ncig. Monel 400 yog tooj liab thiab nickel raws li alloy uas nrov niaj hnub no vim nws qhov kev ua tau zoo. Lub alloy muaj kua qaub zoo heev thiab alkali tsis kam. Tsis tas li ntawd, nws muaj cov zog tensile muaj zog, ductility, zoo heev thermal condactivity, thiab tuaj yeem yog tawv los ntawm kev ua haujlwm txias. Ib qho ntxiv, nws tuaj yeem siv rau hauv cov ntawv thov nrog qhov kub thiab txias txij li rho tawm txog 538 degrees Celsius.

Alloy Hlau Bars & Rods
Duplex2205 Wasters yog dual theem Austentic-Ferritic duplex fasteners thiab molybenum nrog rau cov roj carromium thiab molybenters muaj cov tshuaj tiv thaiv carrosion zoo thiab muaj zog.

ASTM A240 Hom 2205 Phaj yog lub Duplex phaj yog siv ntau yam kev lag luam xws li kev ua yeeb yam, roj thiab roj kev tshawb nrhiav, thiab marine engineering. Sa 240 gr 2205 daim ntawv yog tsim los ntawm qib 220) stainless hlau, uas yog kev sib xyaw ntawm ferritic thiab ustenitic steel.

ASTM B564 FLANCES N06601 flanges Inconel 601 yog npib tsib xee-chromium alloy siv rau cov ntawv thov uas xav tau kev tiv thaiv kom xeb thiab cua sov. Qhov no Nickel alloy sawv tawm vim yog nws cov kev tiv thaiv kub, seem ntawm F. Alloy 60/ dhau los tiv thaiv oxidation oxidation oxide nplai uas tiv taus spalling txawm nyob rau hauv cov xwm txheej ntawm hnyav thermal cycling.

Nws lub zog tensile siab kuj txhais tau tias txo cov txheej txheej phab ntsa tuaj yeem siv tau hauv cov ntawv thov, thiab cov khoom txuag no txhais tau tias txo qis dua lossis txo qhov hnyav ntxiv.

Piv rau Alloy 718, Alloy 625 muaj ntau dua corrosion tsis kam nyob rau hauv ib puag ncig kub.

Nilo Alloy 36, W.NR 1.3912, Tiv Thaiv 36% Nickel-Npib thiab muaj tus nqi ntawm kev nthuav dav ntawm cov hlau.

SMO 254 Cov kav dej tuaj yeem tiv taus cov kev ntxhov siab ntawm cov neeg muaj kev ntxhov siab thiab alloy 254 smo yeeb nkab siab ua haujlwm nyob rau hauv cov kub thiab xeb ib puag ncig.

Cov khoom lag luam hauv paus yog tsim los ua cov kav dej khov kho, muaj lwm txoj hauv kev ruaj ntseg nrog cov hwm ua tau zoo uas AIDS kev ua lag luam kev loj hlob.

Semi-tiav cov ntaub ntawv raw ntawm inconel 625 forged Luj tshim rau dej hiav txwv Cheebtsam thiab cov khoom siv tshuaj lom neeg

Peb muab ntau yam ntawm Astm A335 P9 cocks hlau seamless kav dej siv cov khoom siv raw zoo. Cov alloy Steel P9 ERW cov leeg yog forged nruab nrab ntawm 2250¡Ãf \ 22 feeb¡Ãc) rau 30 feeb ib nti ntawm billet lossis inglot ntu thickness. Cov no yog A335 P9 kav tsim rau cov qauv qauv zoo thoob ntiaj teb. Cov ntaub pua av hlau sib txuas no tseem muaj ntau qhov ntau thiab tsawg, cov qhab nia, thicknesses thiab specifications tshwj xeeb raws li cov neeg siv khoom.

Qeb 304L tau siv dav hauv kev tsim kev lag luam thiab txhua hom qauv vuam tuaj yeem siv tau rau 304L phaj thiab 304l yeeb nkab. Tus "l" nyob rau hauv 304L sawv rau "cov ntsiab lus muaj peev xwm ntawm cov pa roj teeb" thiab qhia tau cov ntsiab lus ntawm cov roj carbon ntau kawg ntawm 0.035%. Tus "H" nyob rau hauv 304h sawv rau "cov ntsiab lus carbon siab", uas txhais tau tias cov ntsiab lus carbon tsis yog qis dua 0.04% thiab tsis ntau tshaj 0.10%.

Qhov no yog hu ua "Center los ntsib" Debive thiab yog sib npaug rau lub vojvoog los ntawm cov astm A234 gr wpb luj tshib yog khoov.

Tsau-nthuav dav iav-encapsulated girapsulated alloys, muaj ib qho kev nthuav dav thermal, muaj ib lub khob hluav taws xob nthuav dav zoo ib yam li qhov ntsuas kub

Stainless hlau B366 WP904L muaj cov ntsiab lus chromium siab dua thiab tiv thaiv cov yeeb nkab ntawm cov kua dej sab hauv.

Featuring 304 Stainless Hlau Rau Heev Zoo Corrosion, Qhov kev pom zoo Weld Neck Flange tuaj yeem txuas nrog lub kaw lus weld ntawm lub caj dab. Welded thaj chaw tuaj yeem raug tshuaj xyuas yooj yim los ntawm radiography. Matched yeeb nkab thiab Flange Bore txo cov cua hlob thiab kev yaig hauv raj dej. Flange yog zoo heev rau siv nyob rau hauv koj daim ntawv thov tseem ceeb thiab yog qhov zoo rau siv nrog huab cua, dej, roj, nkev, thiab chav dej.

Cov kav dej ntawm seamless configurations tau muaj peev xwm ntau dua cov muaj peev xwm thiab lub zog tshaj lwm qib.

304 Piping spools yog tsim los ntawm 304 stainless hlau, ib qho khoom siv nrov thiab nrov tshaj plaws hauv ntau cov ntawv thov uas xav tau kev tiv thaiv kom xeb thiab oxidation. Cov kev tshaj lij no yog preooss siv cov machinery thiab cov txheej txheem tshwj xeeb, uas paub meej tias lawv muaj tseeb thiab ntseeg tau.

Kub lub phaj (HR), Khawb Cuav Txias (CR), 2D, 2D, BA No (8), Satin (tau ntsib nrog cov yas txheej)

304 SS daim ntawv muaj kev tiv thaiv zoo heev rau cov atmospheric corrosion, medolately oxidizing thiab txo cov chaw ib puag ncig, nrog rau kev txhim kho corrosion nyob rau hauv lub welded mob. 304 SS daim ntawv tseem muaj lub zog zoo thiab kev nyuaj ntawm cryogenic kub thiab.
Moj tej tawg, txhuam, etching, thiab lwm yam
Cov lus qhia
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Alloy Steel
Nickel 200 flanges
Ss 316 forged tiaj tus ntsej muag flanges
Hastelloy X Nippolet Flanges Hastelloy X plam ntawm Flanges
Nickel Alloy Fasteners
Invar 36 Tube OD: 0.2-6mm, wt: 0.02-2mm

Alloy 800 Weld Neck Flanges Peb muaj lub koob npe nrov hauv kev lag luam rau kev tsim cov hom kev ua haujlwm zoo uas yuav haum rau peb cov neeg siv khoom. Peb tsim khoom tsim prololoy 800 flanges uas muaj kev ntseeg siab thiab siab dua. Peb siv cov peev txheej hwm thiab qib siab tshaj tawm rau kev tsim ASTM B564 UNFANCES 800 flanges.

ASTM A694 cov hlau roj carbonives yog cov qib feem ntau ntawm cov roj carbon steel siv rau cov bar hloov bar kev loj hlob. Cov ntsiab lus carbon ntau ntxiv ntawm cov alloy txo cov qauv sib zog los ntawm ntau lub zog tensile lub zog. Txawm li cas los xij, cov pa roj carbon muab cov ntsiab lus ntawm cov kab nrog lub peev xwm ua kom tawv thaum thaum lub sijhawm tempering. Qhov no yog vim li cas cov hlau hloov nrog lub hav zoov ntawm cov roj carbon roj carbon me.

Tsis suav txog N08367 tseem hu ua Alloy Al6XN yog cov carbon ntau, siab purity, nitrogen-batoy nrog zoo heev rau chloride pitting thiab compevice corrosion.

Stainless hlau yog qhov zoo tagnrho rau cov ntawv thov ntev lub sijhawm uas yuav ntsib cov ntsiab, noo noo, thiab cov peev xwm tshuaj corrosive.

Vuam ntawm cov alloy no zoo ib yam li ntawm C-22 Alloy. Roj Tungsten Arc Vuam (GTAW) thiab cov thaiv hlau arc vuam (smaw) feem ntau siv rau weld c-276 alloys.

ASTM A240 317 1.4449 2B Ua tiav cov ntawv stainless hlau 321 316L sau ntawv SS 304L - Zhengzhou Huitong Pipeline Equipment Co., Ltd.

Nickel alloy 400 thiab Monel 400, tseem hu ua UN tsis zoo li N04400, yog ib qho laj thawj ntawm cov menyuam yaus uas muaj feem ntau ntawm ob feem peb ntawm ob feem ntawm ob-tus tooj liab. Nickel Alloy 400 yog paub txog nws txoj kev tiv thaiv rau ntau yam ntawm cov kab mob ntawm cov xeb, suav nrog cov alkalis (lossis cov kua qaub), dej hli, thiab sulfuric acid. Txij li thaum Monel 400 lossis Alloy 400 yog cov hlau txias ua haujlwm, cov alloy muaj siab tawv, txhav thiab muaj zog. Los ntawm kev ua haujlwm txias ASTM B14400 Bar Tshuag, cov alloy yog raug rau cov kev ntxhov siab ntau dua, uas nyob rau hauv Alloy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Microy Micro ..
UNRENT: K94610 ASTM F15
Cov lus qhia
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Alloy Steel
Nickel 200 flanges
Ss 316 forged tiaj tus ntsej muag flanges
Caw 36 Cov Lus Qhia Tshwj Xeeb: tsis yog K93600, W.NR 1.3912
Nickel Alloy Fasteners
Invar 36 Tube OD: 0.2-6mm, wt: 0.02-2mm
36 Nti Ansi 150LB Inconel 718 Flange Phaj Flanges N07718 Flange
Duplex Steel Daim Hlau & Cov Ntawv Qhia & Coils

A789 unc unic s31803 thiab unspes ob qib ntawm ob chav stainless hlau uas tau siv dav hauv ntau cov ntawv thov. Cov txiv neej duplex s31803 Seamless kav yog paub rau lawv cov txiv neej ua hauj lwm zoo, muaj lub zog siab, thiab weldability thiab zoo weldability. A789 yog ib qho tshwj xeeb uas tau them seamless thiab welded tub ua los ntawm duplex steel stainless hlau.

Lub 316 cov yeeb nkab stainless hlau tau dhau los ua cov khoom siv tsis tau rau cov kev lag luam lag luam. Qhov no alloy ntawm hlau thiab chrome tau lees paub rau nws lub siab tiv taus corrosion, nrog rau nws cov kav ntev. 316 Stainless hlau Tubing tuaj yeem tsim nyob rau hauv ob leeg seamless thiab welded leeg kom tau raws li cov neeg siv khoom xav tau.
UNRENT: K94610 ASTM F15
Cov lus qhia
htspipe.com
Alloy Steel
Nickel 200 flanges
Ss 316 forged tiaj tus ntsej muag flanges
Caw 36 Cov Lus Qhia Tshwj Xeeb: tsis yog K93600, W.NR 1.3912
Nickel Alloy Fasteners
Invar 36 Tube OD: 0.2-6mm, wt: 0.02-2mm
36 Nti Ansi 150LB Inconel 718 Flange Phaj Flanges N07718 Flange
304L phaj, s30403 coil, stainless hlau phaj

Monel Nickel-Tooj Liab Alloy K-500 Yeeb Nkab khoov thiab Luj tshib sib txuas ua ke ntawm kev ua kom zoo tshaj plaws ntawm Monel alloy 400 nrog rau cov txiaj ntsig zoo dua qub zog thiab hardness.

Ib lub flange yog lub nplhaib ntawm cov hlau (forged, txiav los ntawm phaj, lossis koom nrog cov yeeb nkab ntawm cov yeeb nkab, lossis los koom nrog cov hlab ntsha, lossis mus ua ke lossis lwm qhov chaw sib dhos. Flanges tau koom nrog txhua lwm yam los ntawm kev siv pas dej los ntawm vuam los yog xov (lossis xoob thaum cov quav xaus yog siv). Stainless hlau Flange Tau yooj yim raws li ss flange, nws yog hais txog cov flanges uas ua los ntawm stainless hlau. Cov qauv qauv ib txwm muaj thiab qib AN182% F304 \ / L thiab / L thiab / / /50.

Siab chromium, molybdenum thiab nitrogen cov ntsiab lus cuam tshuam nrog pitting tsis zoo rau cov medtenatent thiab corrosive corrosive conduction, thiab tseem ceeb pitting txias rau tag nrho cov xov xwm, thiab tseem ceeb pitting txias rau saum 50¡Ãc.
Tsis pub dhau cov qeb tshwj xeeb ntawm cov hlau me me yog lwm tus hlau hu ua lub zog loj alloy hlau, lossis hsla rau luv. Txawm hais tias HSLA Screws yog rau cov meli pawg, nws tuaj yeem sau tseg tias HSLA Screws tseem muaj lwm cov ntsiab lus hauv lawv cov alloys, npib tsib xee, vanadium thiab molybdenum.
SAE 304 stainless hlau yog qhov feem ntau steel hlau. Cov hlau muaj ob txoj kev chromium (nruab nrab ntawm 18% thiab 20%) thiab thib pua (nruab nrab ntawm 8%) [1] cov hlau uas yog cov qauv hlau tseem ceeb. Nws yog ib tus neeg siv tshuaj hlau tsis huv. Nws tsis tshua muaj hluav taws xob thiab cuam tshuam cov khoom siv hluav taws xob ntau dua li cov hlau. Nws sib nqus, tab sis tsis sib nqus dua li hlau. Nws muaj ntau dua corrosion tsis kam ntau dua li cov hlau tsis tu ncua thiab siv dav siv vim yog qhov yooj yim nyob rau hauv ntau yam duab. [1]

Npib tsib xee raws 800 incoloy hexagonal yeeb nkab yog paub kom muaj qhov zoo tiv taus corrosion. Tshwj xeeb hais txog kev hais lus, tus incoloy 800 yeeb nkab muaj txaus tiv taus ob carburization zoo li oxidation corrosion.

Qhov no muab kev txhim kho zoo heev rau cov sulfuric acid. Nws kuj tseem muaj cov ntsiab lus chromium siab, kom ua kom zoo dua rau oxidizing tshuaj lom neeg cov tshuaj lom kabmob uas muaj kuab lom thiab yaj oxygen.

Al6XN yog superaustenitic steel hlau nrog kev ua tau zoo rau chloride pitting, crevice corrosion thiab kev nyuaj siab corrosion tawg. Al6XN yog 6 Moly alloy uas tau tsim rau thiab siv hauv kev sib cav sib ceg siab. Nws muaj cov npib tsib xee (24%), Molybdenum (6.3%), nitriumen thiab chromium cov ntsiab lus tawg, thiab tshwj xeeb corrosion tiv thaiv. Al6XN yog feem ntau siv rau nws cov kev txhim kho pitting thiab crevice corrosion tsis kam hauv chlorides. Nws yog ib qho tsim nyog thiab weldable stainless hlau.

Peb muab cov ntaub pua plag alloyOlo 2H Alloy Steel qib 2H Star Wreakers tuaj yeem tsim nyob rau hauv cov qauv ntau lossis kev cai ua rau koj cov kev xav tau tshwj xeeb. Cov neeg siv khoom tuaj yeem siv sijhawm li cas peb muab Alloy Steel qib 2H lub caij nplooj ntoo hlav ntawm kev ua lag luam tus nqi.

Inconel 600 puag ncig bar yog npib tsib xee-raws li benign carburization thiab zoo heev corrosion thiab kub heev. Inconel 600 cov khoom sib txuas ua haujlwm tiv thaiv kom qhuav cl2 thiab ntau lwm cov roj sib txawv ntawm cov mob me thiab kub. Alloy 600 Bar yog npib tsib xee-chromium alloy nrog zoo oxoidation decomposition decomposition decomposition thiab acid oxidation ntawm ntug dej kub.

Hastelloy cov yeeb nkab raj b2 b3 x c22000 c276 sms welded steel yeeb nkab