I. Taw qhia rau stainless hlau:
Tag nrho cov hlau reacts nrog oxygen nyob rau hauv cov huab cua los ua ib tug oxide zaj duab xis nyob rau saum npoo. Hmoov tsis zoo, cov hlau oxide tsim los ntawm cov pa roj carbon zoo tib yam txuas ntxiv mus rau oxidize, ua rau cov xeb kom nthuav tawm tsis tu ncua thiab nws thiaj li tsim qhov. Qhov saum npoo ntawm cov hlau tuaj yeem tiv thaiv los ntawm kev pleev xim lossis electroplating nrog oxidation-resistant hlau (xws li zinc, nickel, thiab chromium). Txawm li cas los xij, raws li tib neeg paub, qhov kev tiv thaiv no tsuas yog ib zaj duab xis nyias xwb. Yog tias cov txheej tiv thaiv puas lawm, cov hlau hauv qab no yuav pib xeb.
Cov hlau uas tiv thaiv tsis muaj zog corrosive media xws li huab cua, chav, thiab dej thiab tshuaj corrosive media xws li acids, alkalis, thiab ntsev. Kuj tseem hu ua stainless acid-resistant steel. Hauv kev siv cov tswv yim, cov hlau uas tsis muaj zog corrosive media feem ntau hu ua stainless hlau, thaum cov hlau uas tawm tsam tshuaj lom neeg hu ua acid-resistant steel. Vim cov tshuaj lom neeg muaj pes tsawg leeg sib txawv ntawm ob, tus qub yuav tsis tas tiv thaiv tshuaj lom neeg corrosion, thaum tom kawg feem ntau muaj cov khoom tsis muaj zog. Kev tiv thaiv corrosion ntawm stainless hlau nyob ntawm cov hlau alloy muaj nyob hauv cov hlau. Chromium yog lub hauv paus ntsiab lus uas ua rau cov hlau tsis muaj steel kom tau txais kev tiv thaiv corrosion. Thaum cov ntsiab lus chromium nyob rau hauv cov hlau nce mus txog 12%, chromium reacts nrog oxygen nyob rau hauv nruab nrab corrosive thiab tsim ib tug heev nyias oxide zaj duab xis (passive zaj duab xis) nyob rau hauv steel nto, uas yuav tiv thaiv tau cov hlau matrix los ntawm ntxiv corrosion. Ntxiv nrog rau chromium, feem ntau siv cov ntsiab lus alloy tseem suav nrog npib tsib xee, molybdenum, titanium, niobium, tooj liab, nitrogen, thiab lwm yam, kom ua tau raws li qhov yuav tsum tau ua ntawm stainless hlau qauv thiab kev ua tau zoo rau ntau yam kev siv.
II. Kev faib tawm ntawm stainless hlau: Stainless hlau feem ntau yog cais raws li cov qauv matrix raws li hauv qab no:
- Ferritic stainless hlau. Muaj 12% - 30% chromium. Nws cov corrosion kuj, toughness, thiab weldability nce nrog nce cov ntsiab lus chromium. Nws muaj kev tiv thaiv zoo dua rau chloride kev nyuaj siab corrosion dua li lwm hom stainless hlau.
- Austenitic stainless hlau. Muaj ntau dua 18% chromium thiab txog 8% npib tsib xee thiab ib qho me me ntawm molybdenum, titanium, nitrogen thiab lwm yam khoom. Nws muaj kev ua haujlwm zoo thiab tuaj yeem tiv thaiv corrosion los ntawm ntau yam xov xwm.
- Austenitic-ferritic duplex stainless hlau. Nws muaj qhov zoo ntawm ob qho tib si austenitic thiab ferritic stainless hlau thiab muaj superplasticity.
- Martensitic stainless hlau. Nws muaj lub zog siab tab sis tsis zoo plasticity thiab weldability.
III. Cov yam ntxwv thiab kev siv ntawm stainless hlau:
IV. Stainless hlau nto kho txheej txheem:
V. Ntim cov yam ntxwv thiab cov khoom tseem ceeb ntawm ntau yam steel mills:
Lwm lub tsev steel mills: Shandong Taigang, Jiangyin Zhaoshun, Xinghua Dainan, Xi'an Huaxin, Southwest, thiab Dongfang Tshwj Xeeb Steel. Cov chaw tsim khoom me me no tsuas yog ua cov ntawv rov qab los ntawm cov ntaub ntawv pov tseg. Lawv cov txheej txheem ntau lawm yog rov qab, cov phaj saum npoo tsis zoo, tsis muaj kev lees paub ntawm cov khoom siv kho tshuab. Cov ntsiab lus tseem ceeb yog yuav luag tib yam li cov chaw tsim khoom loj, tab sis tus nqi pheej yig dua li tib cov qauv ntawm cov chaw tsim khoom loj.
Txawv teb chaws imported steel mills: Shanghai Krupp, South Africa, North America, Nyiv, Belgium, Finland. Cov phaj ntshuam muaj cov txheej txheem ntau lawm, zoo zoo thiab zoo nkauj phaj nto, thiab 整齐 txiav npoo. Tus nqi siab dua li cov qauv hauv tsev ntawm tib hom.
VI. Specifications, qauv, thiab qhov ntau thiab tsawg ntawm stainless hlau: Stainless hlau daim hlau muaj xws li coils thiab thawj daim hlau tiaj tus.
- Cov coils tau muab faib ua cov coils txias dov thiab kub dov coils, trimmed coils thiab untrimmed coils.
- Lub thickness ntawm txias dov coils feem ntau yog 0 3 - 3mm. Kuj tseem muaj cov phaj txias dov nrog lub thickness ntawm 4 - 6 hli. Qhov dav yog 1m, 1219m, thiab 1.5m, txhais los ntawm 2B.
- Lub thickness ntawm kub dov coils feem ntau yog 3 - 14mm. Kuj tseem muaj coil nrog lub thickness ntawm 16 hli. Qhov dav yog 1250, 1500, 1800, thiab 2000, txhais los ntawm NO.1.
- Coils nrog qhov dav ntawm 1.5m, 1.8m, thiab 2.0m yog trimmed coils.
- Qhov dav ntawm untrimmed coils feem ntau yog 1520, 1530, 1550, 2200, thiab lwm yam, uas yog dav dua li qhov dav dav.
- Nyob rau hauv cov nqe lus ntawm tus nqi, tib tus qauv ntawm trimmed coils thiab untrimmed coils feem ntau muaj ib tug nqi sib txawv ntawm txog 300 - 500 yuan.
- Coils tuaj yeem ua kev cai txiav raws li qhov ntev ntawm cov neeg siv khoom. Tom qab flattened los ntawm lub tshuab leveling, lawv hu ua flattened daim hlau. Rau txias dov, nws yog feem ntau flattened rau 1m * 2m, 1219 * 2438, kuj hu ua 4 * 8 ko taw. Rau kub dov, nws yog feem ntau flattened rau 1.5m * 6m, 1.8m * 6m, 2m * 6m. Cov phaj qhib raws li qhov ntau thiab tsawg yog hu ua cov phaj txheem lossis daim hlau ruaj khov.
Thawj daim hlau tiaj tus tseem hu ua single-pass dov daim hlau: - Lub thickness ntawm thawj daim hlau yog feem ntau ntawm 4mm thiab 80mm. Kuj tseem muaj 100mm thiab 120mm thicknesses, thiab cov thickness no tuaj yeem ua kev cai xaj.
- Qhov dav yog 1.5m, 1.8m, thiab 2m, thiab qhov ntev yog ntau tshaj 6 meters.
- Yam ntxwv: Cov phaj qub qub yog qhov loj hauv ntim, tus nqi siab, nyuaj rau pickle, thiab tsis yooj yim rau kev thauj mus los.
VII. Thickness txawv:
- Vim yog me ntsis deformation ntawm dov yob tshwm sim los ntawm cua sov thaum lub sij hawm dov txheej txheem nyob rau hauv lub steel zeb, lub thickness ntawm dov daim hlau qhia deviation, feem ntau thicker nyob rau hauv nruab nrab thiab nyias ntawm ob sab. Thaum ntsuas lub phaj tuab, nws tau teev tseg los ntawm lub xeev tias qhov nruab nrab ntawm lub phaj taub hau yuav tsum ntsuas.
- Qhov laj thawj rau kev kam rau siab yog nyob ntawm kev ua lag luam thiab cov neeg siv khoom xav tau. Feem ntau, nws muab faib ua loj kam rau ua thiab me me kam rau ua.
VIII. Lub ntiajteb txawj nqus tshwj xeeb ntawm ntau yam khoom siv stainless hlau:
- Qhov tshwj xeeb lub ntiajteb txawj nqus ntawm 304, 304L, 304J1, 321, 201, thiab 202 yog 7.93.
- Qhov tshwj xeeb lub ntiajteb txawj nqus ntawm 316, 316L, 309S, thiab 310S yog 7.98.
- Qhov tshwj xeeb lub ntiajteb txawj nqus ntawm 400 series yog 7.75.
IX. Kev suav cov qauv rau stainless hlau:
Kev suav cov qauv:
Stainless hlau yeeb nkab: (sab nraud txoj kab uas hla - phab ntsa thickness) × phab ntsa thickness × 0 02491=Kg/m
Stainless hlau phaj; thickness * (dav × ntev) × lub ntiajteb txawj nqus=Kg/square centimeter
Round steel: (inch × txoj kab uas hla) × 0 00623=Kg/M
Coil nqi: tiaj tus nqi * theoretical thickness / tiag thickness - leveling nqi
Flat phaj nqe: coil nqe * tiag thickness / theoretical thickness + leveling nqi
Theoretical laij lej formula:
Chev phaj: hnyav hnyav ÷ siv thickness (qhov tseeb thickness) × theoretical thickness=theoretical hnyav
Flattened phaj ntawm coil phaj: ntev × dav × thickness × ceev=theoretical nyhav
Medium phaj: ntev × dav × theoretical thickness × ceev=theoretical hnyav
Coil ntev: qhov hnyav ÷ dav ÷ thickness (saib thickness) ÷ ntom=kauj ntev
Qhov tseeb thickness ntawm kauj: trimmed kauj=kauj qhov hnyav ÷ dav ÷ kauj ntev ÷ ceev
Untrimmed coil=(coil hnyav - ntug hlau hnyav) ÷ width ÷ coil length ÷ density
Tus nqi phaj tiaj tus nqi: tus nqi phaj tiaj tus nqi=(coil hnyav * kev lag luam tus nqi - ntug hlau tus nqi + qib tus nqi) / tag nrho qhov hnyav ntawm phaj flattened
Kev piav qhia ntawm qee cov ntsiab lus hauv kev lag luam stainless hlau:
- Tshaj Plaws:
Yog vim li cas: Vim yog vim li cas hauv cov hlau zeb, thaum dov cov phaj tuab, qhov tseeb tuab yog tuab dua li cov qauv tuab, lossis qhov ntev thiab qhov dav ntev dua li tus qauv, ua rau qhov hnyav hnyav dua li qhov ntsuas qhov ntsuas.
Txoj kev hais lus: Ntxiv 200 - 400 yuan / tuj rau cov lus hais txhua hnub, lossis hais lus rau tus neeg siv khoom raws li tus nqi hnyav los ua rau qhov hnyav dua. - Rerolled phaj:
Rerolled daim hlau feem ntau yog tsim los ntawm cov chaw tsim khoom me me los ntawm cov ntaub ntawv pov tseg thiab cov billets. Kev siv thev naus laus zis yog rov qab, lub phaj nto tsis zoo, tsis muaj kev lees paub ntawm cov khoom zoo thiab cov khoom siv, thiab cov ntsiab lus nickel tsis ua raws li cov cai. Hauv kev ua haujlwm, nws yog qhov nyuaj rau kev tho qhov thiab khoov cov xov hlau. Nws qhov zoo dua yog tias tus nqi yog li ntawm 1500 - 2000 yuan pheej yig dua li ntawm cov chaw tsim khoom loj. Rerolled daim hlau feem ntau yog tsim nyob rau hauv Dainan. - Cold-rolled phaj:
Yog vim li cas thiaj ua tau txias dov daim hlau: Vim tias muaj tus nqi loj sib txawv ntawm cov kub dov thiab cov coils txias, thiab cov coils rerolled pheej yig dua li cov coils txias, cov phaj txias dov muaj cov nqi zoo thiab cov txiaj ntsig loj, yog li ntau manufacturers tsim txias-dov daim hlau.
Cov txheej txheem ntau lawm: Cov neeg tsim khoom uas tsim cov ntawv txias-dov tsis muaj peev xwm tsim cov ntawv txias-dov lawv tus kheej. Lawv cov txheej txheem ntau lawm tsis ua raws li qhov yuav tsum tau ua rau kev tsim cov phaj txias. Yog li ntawd lawv yuav kub-dov coils los ntawm cov hlau loj loj, ua qhov chaw annealing thiab kev kho cua sov, thiab tom qab ntawd rov ua dua rau hauv txias-dov coils ntawm ntau thicknesses.
Yam ntxwv: Cov ntaub ntawv qib 1 yog tsim tsis muaj qhov tsis zoo. Cov ntaub ntawv qib thib ob tuaj yeem ua rau khawb thiab xim sib txawv thaum lub sijhawm tsim khoom, tab sis lawv tsis hnyav heev. Tsis muaj qhov sib txawv loj hauv cov khoom siv kho tshuab thiab cov ntsiab lus piv rau cov ntaub ntawv qib thawj. Tus nqi kuj pheej yig dua li cov ntaub ntawv qib thawj. Nws tuaj yeem siv los ntawm cov neeg siv khoom nrog cov kev cai nruj me ntsis! - Qhov sib txawv ntawm L1 thiab LH hauv 201:
L1 txhais tau hais tias cov ntsiab lus npib tsib xee hauv 201 phaj nce mus txog 0.8%; LH txhais tau hais tias cov ntsiab lus nickel hauv 201 phaj nce mus txog 0.6%. Tus nqi ntawm LH kuj pheej yig dua li ntawm L1.
Kev siv thiab cov khoom ntawm ntau hom stainless hlau:
Precipitation hardening stainless hlau. Nws muaj zoo formability thiab weldability thiab yuav siv tau raws li ib tug ultra-high-lub zog khoom nyob rau hauv nuclear kev lag luam, aerospace kev lag luam. Raws li qhov muaj pes tsawg leeg, nws tuaj yeem muab faib ua Cr series (SUS400), Cr-Ni series (SUS300), Cr-Mn-Ni (SUS200) thiab nag lossis daus hardening series (SUS600). 200 series - chromium-nickel-manganese austenitic stainless hlau 300 series.
Precipitation hardening stainless hlau. Nws muaj zoo formability thiab weldability thiab yuav siv tau raws li ib tug ultra-high-lub zog khoom nyob rau hauv nuclear kev lag luam, aerospace kev lag luam.
Raws li qhov muaj pes tsawg leeg, nws tuaj yeem muab faib ua Cr series (SUS400), Cr-Ni series (SUS300), Cr-Mn-Ni (SUS200) thiab nag lossis daus hardening series (SUS600).
200 series - chromium-nickel-manganese austenitic stainless hlau
300 series - chromium-nickel austenitic stainless hlau
301 - Zoo ductility, siv rau molded khoom. Kuj tseem tuaj yeem hardened los ntawm mechanical ceev. Zoo weldability. Zoo hnav tsis kam thiab qaug zog dua li 304 stainless hlau.
302 - Tib yam corrosion kuj zoo li 304. Vim muaj cov ntsiab lus carbon ntau dua, nws muaj zog dua.
303 - Los ntawm kev ntxiv me me ntawm sulfur thiab phosphorus, nws yooj yim dua rau tshuab.
{{0}} Ntawd yog, 18/8 stainless hlau. Qib GB yog 0Cr18Ni9.
309 - Nws muaj qhov ntsuas kub zoo dua li 304.
316 - Tom qab 304, nws yog qhov thib ob feem ntau siv steel hom. Feem ntau siv hauv kev lag luam khoom noj khoom haus thiab cov cuab yeej phais. Ntxiv cov ntsiab lus molybdenum muab nws cov qauv tshwj xeeb los tiv thaiv corrosion. Vim nws zoo dua rau chloride corrosion dua 304, nws kuj yog siv los ua "shipbuilding steel". SS316 feem ntau yog siv rau hauv cov khoom siv hluav taws xob nuclear. 18/10 qib stainless hlau feem ntau kuj ua tau raws li daim ntawv thov no. [1]
Qauv 321 - Tsuas yog ntxiv cov ntsiab lus titanium los txo qhov kev pheej hmoo ntawm vuam corrosion ntawm cov khoom, lwm yam khoom zoo ib yam li 304.
400 series - ferrite thiab martensitic stainless hlau
408 - Cov cua kub zoo, tsis muaj zog corrosion, 11% Cr, 8% Ni.
409 - Cov qauv pheej yig tshaj plaws (hauv Tebchaws Askiv thiab Tebchaws Meskas), feem ntau yog siv los ua cov kav dej hauv tsheb, yog cov ferrite stainless hlau (chromium steel).
410 - Martensitic (high-strength chromium steel), hnav tsis kam, tsis zoo corrosion kuj.
416 - Ntxiv sulfur txhim kho kev ua haujlwm ntawm cov khoom siv.
420 - "Tool grade" martensitic steel, zoo ib yam li cov hlau tsis muaj zog tshaj plaws xws li Buehler siab chromium hlau. Kuj tseem siv rau riam phais thiab tuaj yeem ua kom ci ntsa iab heev.
430 - Ferrite stainless hlau, rau kev kho kom zoo nkauj, xws li cov khoom siv tsheb. Zoo formability, tab sis tsis zoo kub tsis kam thiab corrosion kuj.
440 - Cov cuab yeej muaj zog steel nrog cov ntsiab lus siab dua me ntsis. Tom qab kev kho cua sov kom zoo, nws tuaj yeem tau txais lub zog ntau dua. Lub hardness yuav ncav cuag 58HRC thiab belongs rau lub hardest stainless hlau. Qhov feem ntau siv piv txwv yog "razor blade". Muaj peb hom qauv siv: 440A, 440B, 440C. Tsis tas li ntawd, muaj 440F (yooj yim-rau-tus txheej txheem hom).
500 series - kub-resistant chromium alloy hlau.
600 series - martensitic nag lossis daus hardening stainless hlau.
630 - Feem ntau siv nag lossis daus hardening stainless hlau qauv, feem ntau kuj hu ua 17-4; 17% Cr, 4% N.
Common stainless hlau nto kho technologies muaj cov hauv qab no txoj kev kho:
① Nto ntuj kho hniav; ② Nto daim iav ci kev kho mob; ③ Kev kho deg xim.
1.3.1 Surface natural whitening treatment: Thaum lub sij hawm ua cov hlau tsis muaj steel, los ntawm cov txheej txheem xws li coiling, hemming, vuam, los yog cov khoom siv hluav taws xob cua sov kho, dub oxide scale yog generated. Qhov nyuaj grey-dub oxide nplai no feem ntau muaj ob yam EO4, NiCr2O4 thiab NiF. Yav dhau los, muaj zog corrosive txoj kev xws li hydrofluoric acid thiab nitric acid feem ntau yog siv los tshem tawm nws. Txawm li cas los xij, txoj kev no muaj tus nqi siab, ua rau ib puag ncig, muaj kev phom sij rau tib neeg lub cev, thiab muaj zog corrosiveness. Nws tau maj mam tshem tawm. Tam sim no, muaj ob txoj hauv kev los kho oxide nplai:
(1) Sandblasting (steev blasting) txoj kev: Feem ntau yog siv cov txheej txheem ntawm txau micro iav hlaws kom tshem tawm cov xim dub oxide ntawm qhov chaw.
(2) Cov txheej txheem tshuaj: Siv cov tshuaj tsis muaj kuab lom thiab tsis muaj kuab lom thiab tshuaj tua kab mob thiab tshuaj ntxuav nrog cov tshuaj inorganic additives uas tsis muaj tshuaj lom nyob rau hauv chav tsev kub rau immersion ntxuav. Yog li, lub hom phiaj ntawm kev kho hniav dawb ntawm stainless hlau lub ntuj xim yog tiav. Tom qab kev kho mob, nws yeej zoo li matte xim. Txoj kev no yog qhov tsim nyog rau cov khoom loj thiab nyuaj.
1.3.2 Stainless hlau nto iav ci kev kho mob txoj kev: Raws li qhov nyuaj ntawm stainless hlau cov khoom thiab cov neeg siv yuav tsum tau, mechanical polishing, tshuaj polishing, thiab electrochemical polishing txoj kev yuav siv tau los ua kom tiav daim iav gloss. Qhov zoo thiab qhov tsis zoo ntawm peb txoj kev no yog raws li hauv qab no:
1.3.3 Cov xim pleev xim rau saum npoo: Cov xim hlau stainless tsis tsuas yog muab cov khoom siv stainless hlau ntau xim, ua rau ntau yam khoom, tab sis kuj txhim kho cov hnav tsis kam thiab corrosion kuj ntawm cov khoom.
Muaj cov txheej txheem xim hauv qab no rau stainless hlau:
(1) Tshuaj oxidation xim txoj kev;
(2) Electrochemical oxidation xim txoj kev;
(3) Ion deposition oxide xim txoj kev;
(4) Kub-kub oxidation xim txoj kev;
(5) Gas theem tawg xim txoj kev.
Lub ntsiab lus luv luv ntawm ntau txoj hauv kev yog raws li hauv qab no:
(1) Tshuaj oxidation coloring method: Hauv ib qho kev daws teeb meem, cov xim ntawm zaj duab xis yog tsim los ntawm cov tshuaj oxidation. Muaj txoj kev dichromate, sib xyaw sodium ntsev txoj kev, txoj kev sulfidation, acidic oxidation txoj kev, thiab alkaline oxidation txoj kev. Feem ntau, "INCO method" yog siv ntau dua. Txawm li cas los xij, yog tias koj xav kom muaj xim zoo ib yam ntawm cov khoom lag luam, cov khoom siv electrode yuav tsum tau siv los tswj.
(2) Electrochemical coloring method: Hauv ib qho kev daws teeb meem, cov xim ntawm zaj duab xis yog tsim los ntawm electrochemical oxidation.
(3) Ion deposition oxide coloring method chemical method: Muab cov stainless hlau workpiece tso rau hauv lub tshuab nqus tsev txheej rau lub tshuab nqus tsev evaporation plating. Piv txwv li, saib cov rooj plaub thiab saib pluaj plated nrog titanium kub feem ntau yog xim daj. Txoj kev no tsim nyog rau kev ua cov khoom lag luam ntau. Vim tias kev nqis peev loj thiab tus nqi siab, nws tsis raug nqi rau cov khoom me me.
(4) High-temperature oxidation coloring method: Nyob rau hauv ib qho tshwj xeeb molten ntsev, raus lub workpiece thiab tswj nws ntawm tej yam txheej txheem tsis ua rau lub workpiece tsim ib tug oxide zaj duab xis ntawm ib tug tej thickness thiab nthuav ntau yam xim.
(5) Gas theem cracking coloring method: Nws yog ib qho nyuaj thiab tsis siv nyob rau hauv kev lag luam.
1.3 Xaiv txoj kev kho mob
Rau stainless hlau nto kho, txoj kev tsim nyog yuav tsum tau xaiv raws li cov qauv khoom, cov khoom siv, thiab qhov sib txawv ntawm qhov yuav tsum tau ua.
Lub ntsiab lus ntawm SUS: SUS yog cov cai rau stainless hlau hauv Japanese JIS tus qauv.
Thaum cov txheej txheem Japanese tau tshaj tawm, lawv txhua tus tuaj nrog cov lus piav qhia. Nyob rau hauv cov kab lus txuas ntxiv ntawm cov lus piav qhia, cov txheej txheem evolution ntawm steel tooj nqis thiab cov yam ntxwv thiab kev siv ntawm cov tooj hlau uas tau teev tseg hauv cov qauv tau piav qhia. Yog tias tus naj npawb steel hauv Nyij Pooj yog ib hom khoom tuaj ntawm Tebchaws Meskas, lub npe "SUS" (steel use stainless) yog ntxiv ua ntej peb tus lej. Tab sis qhov txawv ntawm ASTM (American Society for Testing and Materials) yog tias nws yog tus lej hlau tsim los ntawm Nyiv nws tus kheej, cov lus "J" qhia txog Nyiv. Piv txwv li, "SUS 316J1" txawv ntawm "SUS 316".
Dab tsi yog qhov hardness ntawm SUS316 stainless hlau?
304 yog qhov tsis zoo ntawm kev hnav tsis kam thiab kub tsis kam. Muaj qhov sib txawv me me ntawm cov hlau nplaum. Yuav muaj qhov tshwm sim tsis muaj zog hlau nplaum tom qab ua tiav, tab sis nws tuaj yeem raug tshem tawm los ntawm kev siv tshuab tom qab. Lub hardness ntawm 316 rau nruab nrab daim hlau, nyias daim hlau, thiab strips tom qab kho (HRB)<>.
Qhov ob feem ntau siv stainless hlau tam sim no yog 304 thiab 316 (los yog sib haum rau 1.4308 thiab 1.4408 hauv German
