Vim li cas thiaj siv 304L Phaj Hloov 304?

304L yog tsim nyog rau tus nqi qis tshaj plaws thaum twg koj lub phaj yuav raug welded, raug rau ib puag ncig corrosive tom qab vuam, los yog siv nyob rau hauv ib tug txheej txheem uas txawm trace carbide nag lossis daus tuaj yeem cuam tshuam kev ua haujlwm. Rau cov khoom siv kho kom zoo nkauj lossis cov qauv siv uas tsis muaj vuam, tus qauv 304 zoo kawg nkaus. Kab lus no piav qhia meej vim li cas - nrog cov ntaub ntawv.

Why Use 304L Plate Instead of 304

304i ib304L Stainless hlauyog ob leeg cov tswv cuab ntawm tib tsev neeg austenitic stainless hlau - 18% chromium, 8-9% npib tsib xee, tsis muaj molybdenum. Nyob rau hauv lub annealed ( zeb-muab) phaj mob, lawv zoo tib yam, zoo tib yam, thiab ua zoo tib yam. Qhov sib txawv ntawm lawv yog ib tus lej: cov ntsiab lus carbon.

Standard 304tso cai carbon mus txog 0.08%.304L txwv cov pa roj carbon ntau tshaj 0.030% - tsawg dua ib nrab ntawm 304. Tus "L" hauv 304L tsuas yog sawv cev rau "Low Carbon." Qhov kev txwv ntawd hloov pauv cov alloy tus cwj pwm hauv qhov tshwj xeeb tab sis tseem ceeb heev: vuam.

Khoom	304 (Standard)	304L (Cov pa roj carbon tsawg)	Tswv yim cuam tshuam
Cov ntsiab lus carbon (max)	0.08%	0.030%	Qhov txawv txav
Chromium cov ntsiab lus	18.0–20.0%	18.0–20.0%	Zoo ib yam
Nickel cov ntsiab lus	8.0–10.5%	8.0–12.0%	Ntau qhov dav me ntsis hauv 304L
Manganese (max)	2.00%	2.00%	Zoo ib yam
Silicon (max)	0.75%	0.75%	Zoo ib yam
Min. tensile zog	515 MPa ua	485 MPa ua	304 marginally muaj zog (annealed)
Min. yield zog	205 MPa	170 MPa	304 marginally ntau dua tawm los
Elongation (min.)	40%	40%	Sib npaug ductility
Corrosion kuj (annealed)	Zoo heev	Zoo heev	Sib npaug nyob rau hauv annealed mob
Corrosion kuj (post-weld)	Txo hauv HAZ	Zoo heev - tsis muaj rhiab heev	304L txiav txim kom zoo dua
Tus nqi ntawm cov khoom siv txheeb ze	Lub hauv paus	+3–8% hwm	Tus nqi me me rau kev tiv thaiv loj
Raws li ASTM A240	Yog lawm	Yog lawm	Ob leeg tsim nyog raws li tus qauv qub

The Real Reason 304L Exists Sensitization

Yuav kom nkag siab tias yog vim li cas 304L yog qhov zoo tshaj rau feem ntau cov ntawv thov kev lag luam, koj yuav tsum nkag siab txog ib lub tswv yim tseem ceeb ntawm metallurgical: rhiab heev. Nws suab technical, tab sis lub tswv yim yog yooj yim.

Thaum twg tus qauv austenitic stainless hlau - suav nrog 304 - yog rhuab mus rau qhov kub ntawm 425℃thiab 850℃(uas yog raws nraim li cas tshwm sim nyob rau hauv lub tshav kub- cuam tshuam cheeb tsam ntawm weld), carbon atoms uas yaj nyob rau hauv cov hlau tsiv mus rau lub grain ciam teb - lub microscopic siv lead ua ib tug ciam teb ntawm {6} cov ntaub ntawv nyob rau hauv ib tug tib neeg cov ntaub ntawv nyob rau hauv lub cheeb daim ntawv chromium carbides (Cr₂₃C₆).

Qhov tshwm sim yog ib cheeb tsam nqaim raws txhua tus ciam teb uas ua rau muaj kev puas tsuaj loj hauv chromium. Cov cheeb tsam depleted no poob lawv cov corrosion{1}}resistant passive zaj duab xis. Nyob rau hauv ib puag ncig uas muaj ya raws, acids, chlorides, los yog oxygen - uas yog hais tias, yuav luag txhua yam tiag tiag - ntiaj teb kev lag luam ib puag ncig - cov cheeb tsam depleted no ua cov ntsiab lus rau kev cuam tshuam rau intergranular corrosion (tseem hu ua "weld decay"). Cov hlau tuaj yeem saib zoo kawg nkaus rau ntawm qhov chaw thaum intergranular corrosion yog ntsiag to rhuav tshem nws los ntawm sab hauv.

304L tshem tawm qhov kev pheej hmoo no los ntawm kev tshem tawm cov hauv paus hauv paus. Nrog rau cov pa roj carbon tsawg dua los yog sib npaug li 0.030%, tsuas yog tsis muaj cov pa roj ntau txaus los tsim cov chromium carbides tseem ceeb ntawm cov ciam teb, txawm tias cov hlau tau rhuab los ntawm qhov kev xav tau ntau yam thaum lub sij hawm vuam. Qhov tshwm sim: tag nrho corrosion kuj yog khaws cia nyob rau hauv lub vuam cua sov- cuam tshuam cheeb tsam (HAZ) yam tsis muaj kev tshaj tawm -weld tshav kub kho.

1. Tsis muaj rhiab heev tom qab vuam

Qhov no yog lub ntsiab kom zoo dua. Tej fabrication uas muaj welding - TIG, MIG, plasma, los yog kuj welding - yuav ua rau lub hauv paus hlau mus rau qhov kub thiab txias nyob rau hauv lub sensitization ntau yam. Nrog 304, qhov ntawd txhais tau hais tias lub tshav kub- thaj tsam cuam tshuam ua rau muaj kev pheej hmoo corrosion. Nrog 304L, cov ntsiab lus carbon tsawg ua rau cov hlau tsis muaj zog rau kev nkag siab. Tsis muaj kev tshaj tawm -weld annealing yog yuav tsum tau, txuag lub sij hawm thiab fabrication nqi.

2. Tshaj tawm -Kev kho cua sov tsis tas yuav tsum tau ua

Yuav kom "kho" sensitized 304 welds, fabricators yuav tsum ua ib tug ncej -weld tov annealing tshav kub kev kho mob - cua sov tag nrho cov sib dhos rau ib ncig ntawm 1,050℃thiab sai sai quenching nws. Rau cov hlab ntsha loj, cov tso tsheb hlau luam, lossis cov khoom tsim tawm nyuaj, qhov no kim heev, lub sijhawm- siv, thiab qee zaum lub cev tsis tuaj yeem. 304L tshem tawm qhov yuav tsum tau ua rau feem ntau cov ntawv thov.

3. Sib npaug Corrosion Resistance rau 304 nyob rau hauv lub Annealed Condition

Ib qho kev xav tsis zoo yog tias 304L cov ntsiab lus qis dua qee qhov txo nws qhov kev tiv thaiv corrosion. Tsis yog. Nyob rau hauv qhov kev mob annealed - ua ntej yuav muaj qhov vuam siv qhov chaw - 304 thiab 304L muaj qhov zoo tib yam corrosion kuj. Cov ntsiab lus chromium thiab npib tsib xee (qhov tseeb corrosion-cov khoom tiv taus) yog tib yam hauv ob qib. 304L tsuas yog ua tau zoo tshaj 304 tom qab thermal raug.

4. Daim ntawv pov thawj Dual: 304 / 304L

Ntau lub mills tsim stainless hlau phaj uas ib txhij ua tau raws li ob qho tib si 304 thiab 304L cov kev xav tau - qhov no yog hu ua dual- ntawv pov thawj lossis dual- qib phaj. Vim hais tias 304L qhov muaj pes tsawg leeg yog ib feem ntawm 304's, txhua lub rooj sib tham phaj 304L kuj ua tau raws li 304. Dual-cov ntawv pov thawj muab cov neeg yuav khoom siab tshaj plaws: cov phaj tuaj yeem siv rau hauv txhua daim ntawv thov uas qhia txog qib twg, tsis muaj kev nplua nuj.

5. Kev Lag Luam thiab Kev Txais Cai

304L tau lees paub thiab tshwj xeeb yuav tsum tau lossis nyiam nyob rau hauv ntau cov khoom noj, tshuaj, tshuaj, thiab cov hlab ntsha siab kom meej meej vim nws cov lus zoo tshaj -weld corrosion cwj pwm. ASME Boiler thiab Pressure Vessel Code (ASME BPVC), FDA cov txheej txheem khoom noj khoom haus, thiab European Pressure Equipment Directive (PED) txhua tus paub thiab haum 304L raws li qhov kev xaiv zoo tshaj rau cov khoom siv stainless hlau welded.

Daim ntawv thov Scenario	Pom zoo Qib	Yog vim li cas
Welded nkoj, tso tsheb hlau luam, lossis cov kav dej hauv ib puag ncig	304L	Tshem tawm qhov kev pheej hmoo ntawm kev puas tsuaj hauv tshav kub- thaj chaw cuam tshuam
Cov khoom siv ua zaub mov nrog welded pob qij txha	304L	FDA / kev nyiam huv cov lej nyiam 304L rau cov khoom noj khoom haus welded-cov chaw tiv tauj
Chemical cog piping raug rau cov kua qaub los yog chlorides	304L	Ib puag ncig corrosive ua kom pom kev puas tsuaj
Pharmaceutical bioreactor thiab CIP system fabrication	304L	Cleanability thiab corrosion kuj yuav tsum ciaj sia rov welding
Daim ntawv kho kom zoo nkauj, cladding - tsis muaj vuam	304 los yog 304L	Qib twg ua tau zoo ib yam thaum annealed; 304 yog me ntsis pheej yig dua
Cov txheej txheem framing, brackets - tsis muaj corrosive raug	304 los yog 304L	Kev hnov mob tsis muaj kev pheej hmoo yog tias tsis muaj kev tshaj tawm corrosive
Siab -kev pabcuam kub siab tshaj 400℃(sustained)	Tsis yog - xav txog 316H lossis 321	Ob leeg 304 thiab 304L tau txwv siab -temp. tso cai rau kev nyuaj siab
Cov peev nyiaj- tseem ceeb, tsis yog-welded, tsis yog- daim ntawv thov corrosive	304	Tus nqi qis dua; tag nrho kev ua tau zoo nyob rau hauv annealed mob

Cov xov xwm zoo: 304L tus nqi tsuas yog marginally ntau dua 304. Tus nqi me me qhia txog cov kev tswj xyuas nruj dua uas yuav tsum tau ua thaum lub sij hawm steelmaking, tsis yog qhov sib txawv ntawm cov khoom siv raw. Feem ntau, dual- ntawv pov thawj 304/304L phaj yog muaj nyob rau ntawm tsis muaj nqi dab tsi, txij li feem ntau niaj hnub mills niaj hnub ua tau zoo carbon qib nyob rau hauv 304L ntau yam.

304L vs 304 Plate Price Per kg

Thaj tsam	304 Plate (USD / kg)	304L Phaj (USD / kg)	Hwm	Sau ntawv
Tuam Tshoj (mills / FOB)	$2.20 – $3.20	$2.35 – $3.40	~5–8%	Dual daim ntawv pov thawj. feem ntau muaj yam tsis muaj nqi
Is Nrias teb (mills / FOB)	$2.50 – $3.60	$2.65 – $3.80	~5–7%	Kev loj hlob muaj peev xwm; kev sib tw
Teb chaws Europe (distributor)	$4.00 – $5.80	$4.20 – $6.10	~5–8%	PED ntawv pov thawj; hwm rau daim ntawv pov thawj
Tebchaws Asmeskas (hauv tsev)	$4.50 – $6.50	$4.70 – $6.80	~3–6%	Tshooj 232 tariffs siv rau ntshuam
Kaus lim qab teb / Nyiv	$3.20 – $4.50	$3.40 – $4.70	~4–7%	High-kev tsim khoom zoo; JIS- ntawv pov thawj muaj

Nqe Disclaimer: Cov nqi saum toj no yog qhov qhia tau Q1-2025 cov qauv ntsuas raws li cov ntaub ntawv tshaj tawm hauv khw. Tus nqi tseeb hloov pauv nrog LME nickel thiab chromium kev lag luam. Thov ib daim ntawv hais los ntawm koj tus neeg muab khoom tam sim no, qhov project- tus nqi tshwj xeeb. Tus nqi yog FOB lossis ex- ua haujlwm tshwj tsis yog hais.

Cov neeg muag khoom hauv qab no muab kev ntseeg siab 304L phaj nrog cov ntaub ntawv zoo. Txhua qhov kev nkag suav nrog kev taw qhia txog tus nqi tshwj xeeb, muaj peev xwm ua pov thawj, thiab lub laj thawj meej meej vim li cas lawv raug pom zoo.

Where to Buy 304L Stainless Steel Plate 4 Recommended Suppliers

#01 JN Alloy (Jinie Technology, Jiangsu)- Wuxi, Suav teb
Lub vev xaib	www.jnalloy.com
304 Phaj Nqe / kg	$ 2.20 - $ 3.20 / kg (FOB Suav chaw nres nkoj)
304L Phaj Nqe / kg	$ 2.35 - $ 3.40 / kg (FOB Suav chaw nres nkoj)
Cov ntawv pov thawj	ISO 9001, CE / PED, ASME, EN 10204 3.1 / 3.2, SGS / BV / TUV thib peb- tog
Min. Order Qty	100 kg ib kab; thawv loads nyiam rau tus nqi zoo tshaj
Lub Sijhawm Lead	7-15 hnub (kwv yees); 3-6 lub lis piam (tsis yog- qhov loj me)
Zoo tshaj rau	Ntiaj teb no export, zaub mov/pharma qib, ASME siab nkoj, tshuaj nroj tsuag

Vim li cas thiaj xaiv tus neeg muag khoom no:JN Alloy yog cov chaw tsim khoom lag luam suav nrog ntsug thiab thoob ntiaj teb xa tawm nrog 20+ xyoo ntawm kev paub hauv 304L phaj mov. Lawv tsis tu ncua tsim dual- ntawv pov thawj 304/304L phaj rooj sib tham EN 10204 3.1 thiab tuaj yeem npaj 3.2 thib peb- kev tshuaj xyuas tog ntawm kev thov. Tshwj xeeb tshaj yog pom zoo rau cov neeg yuav khoom hauv Asia, Middle East, thiab cov lag luam tawm tshiab uas xav tau ASME lossis EN- ntawv pov thawj 304L ntawm tus nqi sib tw. Lawv qhov kev sim PMI thiab tag nrho cov tshuaj traceability ua rau lawv tsim nyog rau kev ua zaub mov thiab kev ua lag luam.

#02 Stainless hlau- Helsinki, Finland (mills hauv lub teb chaws Yelemees, Sweden, USA)
Lub vev xaib	www.outokumpu.com
304 Phaj Nqe / kg	$4.00 – $5.60 / kg (Tebchaws Europe, ex-ua haujlwm)
304L Phaj Nqe / kg	$4.20 – $5.80 / kg (Tebchaws Europe, ex-ua haujlwm)
Cov ntawv pov thawj	TS EN 10028-7, PED 2014/68 / EU, ASME SA-240, FDA 21 CFR, Lloyd's, DNV
Min. Order Qty	1 tonne yam tsawg kawg nkaus; txiav - mus rau - loj muaj
Lub Sijhawm Lead	2-5 hnub (Tebchaws Europe Tshuag); 4-8 lub lis piam (mill dov)
Zoo tshaj rau	European PED-cov khoom siv tau ntawv pov thawj, qib zaub mov, tshuaj reactors

Vim li cas thiaj xaiv tus neeg muag khoom no:Outokumpu yog Europe tus loj tshaj plaws stainless hlau tsim thiab tus qauv kub rau EU PED-raws li 304L phaj. Lawv tag nrho cov khoom tsim tawm - los ntawm cov khoom siv raw mus rau cov phaj tiav - muab cov ntaub ntawv tsis sib xws thiab cov ntaub ntawv pov thawj seamless. Rau European fabricators tsim cov hlab ntsha raws li PED 2014/68/EU, ATEX, los yog FDA- tswj cov khoom ua zaub mov, Outokumpu- keeb kwm 304L yog thawj -kev xaiv specification. Lawv cov ntaub ntawv pov thawj kev ruaj ntseg (tsawg- cov pa roj carbon ntau, cov ntsiab lus rov ua dua) kuj tseem muaj nuj nqis los ntawm ESG- pab pawg neeg yuav khoom.

#03 Hlau Depot / Service Center (USA)- Winchester, Kentucky, Tebchaws USA
Lub vev xaib	www.metalsdepot.com
304 Phaj Nqe / kg	$ 4.80 - $ 6.50 / kg (USA, suav nrog kev txiav txiav)
304L Phaj Nqe / kg	$ 5.00 - $ 6.80 / kg (USA, suav nrog kev pabcuam txiav)
Cov ntawv pov thawj	ASTM A240, ASME SA-240, EN 10204 2.2 / 3.1, muaj nyob hauv keeb kwm
Min. Order Qty	Tsis muaj yam tsawg kawg nkaus rau cov qauv Tshuag loj; kev cai txiav los ntawm 1 daim
Lub Sijhawm Lead	Tib -hnub mus rau 3 hnub ua haujlwm (cov khoom lag luam)
Zoo tshaj rau	Cov me me-batch US fabricators, prototype/R&D, sai-turnaround project

Vim li cas thiaj xaiv tus neeg muag khoom no:Rau North American fabricators uas xav tau 304L phaj txiav kom meej qhov ntev ntawm daim ntawv ceeb toom luv luv - hnub ntau dua li lub lis piam - US chaw pabcuam xws li Metals Depot yog cov kev daws teeb meem. Lawv tuav 304L phaj cov khoom lag luam thoob plaws cov tuab tuab (3-25 hli) thiab tuaj yeem xa cov txiav - mus rau - loj nrog ASTM A240 ntawv pov thawj. Tus nqi yog siab dua zeb- ncaj qha Suav los yog Indian qhov chaw, tab sis tus nqi yog nyob rau hauv tam sim no muaj thiab xoom yam tsawg kawg nkaus txiav txim, ua rau lawv zoo tagnrho rau prototyping, kho, thiab ceev hloov txoj hauj lwm.

#04 TISCO / Baosteel (Premier Suav Mills)- Taiyuan / Shanghai, Suav
Lub vev xaib	www.tisco.com.cn / www.baosteel.com
304 Phaj Nqe / kg	$2.20 – $3.00 / kg (ex-ua haujlwm Suav teb)
304L Phaj Nqe / kg	$2.35 – $3.20 / kg (ex-ua haujlwm Suav teb)
Cov ntawv pov thawj	EN 10204 3.1, ASTM A240, ISO 9001, SGSS, BV, DNV, qib nuclear muaj
Min. Order Qty	20-50 tonne yam tsawg kawg nkaus kev txiav txim zeb; me me los ntawm kev tso cai distributors
Lub Sijhawm Lead	15-30 hnub rau cov qauv loj; 6-10 lub lis piam rau tsis yog- qauv
Zoo tshaj rau	Loj - ntim cov neeg yuav khoom, EPC cov neeg cog lus, kev yuav khoom

Vim li cas thiaj xaiv tus neeg muag khoom no:TISCO (Taiyuan Hlau thiab Hlau) thiab Baosteel yog Tuam Tshoj tus premier stainless hlau mills thiab ntawm cov loj tshaj plaws stainless manufacturers nyob rau hauv lub ntiaj teb no. Lawv 304L phaj yog tsim nyob rau hauv cov txheej txheem zoo nrog tag nrho cov cua sov traceability, thiab lawv tuav EN 10204 3.1 ntawv pov thawj raws li tus qauv. Rau qhov loj - ntim qhov project procurement (50+ tonnes), yuav ncaj qha los ntawm TISCO lossis Baosteel tso cai tus xa khoom xa tus nqi qis tshaj -tsim tau rau - kilogram nqi nrog tag nrho cov ntawv pov thawj zeb. Txoj kev no tau pom zoo tshwj xeeb rau EPC cov neeg cog lus hauv cov roj thiab roj, desalination, thiab chemical cog kev tsim kho uas tuaj yeem npaj kev yuav khoom 6-8 lub lis piam ua ntej.

Q: Puas yog 304L zoo ib yam li 304 stainless hlau?

A: Lawv yuav luag zoo tib yam - tib cov ntsiab lus chromium, npib tsib xee, thiab molybdenum; zoo li qub; tib yam corrosion kuj nyob rau hauv lub annealed mob. Qhov sib txawv tsuas yog cov ntsiab lus carbon: 304 tso cai rau 0.08% carbon, thaum 304L txwv cov pa roj carbon rau 0.030% siab tshaj. Qhov sib txawv ib leeg no ua rau 304L tiv taus ntau dua rau kev hnov qab thiab intergranular corrosion tom qab vuam. Nyob rau hauv tag nrho lwm yam, cov qhab nia sib pauv tau.

Q: Puas yog 304L muaj zog dua 304?

A: Tsis yog . 304 yog marginally muaj zog tshaj 304L nyob rau hauv lub annealed mob. ASTM A240 lub zog tensile yam tsawg kawg nkaus rau 304 yog 515 MPa piv rau 485 MPa rau 304L, thiab lub zog qis kawg nkaus yog 205 MPa piv rau 170 MPa. Txawm li cas los xij, hauv ntau qhov tiag -kev siv hauv ntiaj teb no qhov sib txawv no tsis yog tsim- qhov tseem ceeb, tshwj xeeb tshaj yog vim ob qib muaj qhov sib npaug (40%) thiab weldability. Qhov kev ua tau zoo ntawm 304L yog nyob rau tom qab-weld corrosion kuj, tsis muaj zog txhua yam.

Q: Kuv puas tuaj yeem hloov 304 rau 304L hauv daim ntawv thov welded?

A: Koj tuaj yeem - tab sis koj tuaj yeem ua rau muaj kev pheej hmoo corrosion hauv tshav kub- thaj chaw cuam tshuam yog tias lub vuam raug rau ib puag ncig corrosive. Kev txo qis rau 304 yog tom qab-weld tov annealing (cua sov rau ~ 1,050℃thiab quenching), uas dissolves cov carbides thiab restores tag nrho corrosion kuj. Yog tias tom qab-weld annealing yog ua tau thiab tag nrho cov kev sib dhos tuaj yeem ua kom sov- kho, 304 yog qhov siv tau. Nyob rau hauv feem ntau cov tswv yim fabrication scenarios, qhov no yog ib qho impractical lossis kim heev, uas yog vim li cas 304L muaj thiab nyiam.

Q: "Dual certified 304/304L" txhais li cas?

A: Ib daim ntawv thib ob - ntawv pov thawj ua tau raws li 304 thiab 304L muaj pes tsawg leeg thiab cov khoom siv tshuab ib txhij. Vim tias 304L cov pa roj carbon ntau tshaj (0.030%) yog qis dua 304 qhov siab tshaj plaws (0.08%), txhua phaj nrog cov pa roj carbon tiag tiag ntawm 0.030% lossis qis dua tuaj yeem ua tau raws li ob qib. Ntau lub mills niaj hnub niaj hnub ua tiav qhov no, yog li daim ntawv pov thawj dual tsis muaj tus nqi hwm thiab muab cov neeg yuav khoom yooj yim siv lub phaj tiv thaiv ob qho tshwj xeeb. Ib txwm txheeb xyuas cov ntsiab lus ntawm cov pa roj carbon monoxide nyob rau hauv daim ntawv qhia txog kev ntsuas zeb (MTR) es tsis yog cia siab rau daim ntawv qhia qib ib leeg.

Q: Qhov twg yog qhov chaw zoo tshaj plaws los yuav 304L stainless hlau phaj?

A: Rau cov phiaj xwm thoob ntiaj teb ntawm tus nqi sib tw, Suav mills (TISCO, Baosteel) lossis cov kws tshaj lij xa tawm xws li JN Alloy muab EN 10204 3.1 tau ntawv pov thawj 304L phaj ntawm $ 2.35–3.40 / kg FOB. Rau European PED-cov haujlwm tau lees paub, Outokumpu lossis Thyssenkrupp yog cov qauv kev xaiv. Rau North American me me -batch lossis xaj xaj sai, Asmeskas cov chaw pabcuam muab tib yam - hnub xa khoom. Qhov zoo tshaj plaws yog nyob ntawm koj qhov kev txiav txim ntim, lub sijhawm ua haujlwm, qhov yuav tsum tau ua daim ntawv pov thawj, thiab qhov chaw xa khoom.