ASTM A252 Qib 2 yog ib qho kev qhia tshwj xeeb los ntawm ASTM International (yav tas los hu ua American Society for Testing and Materials) rau welded thiab seamless steel yeeb nkab pawg.
ASTM A252, ASTM A252: Cov qauv no suav nrog cov nominal (nruab nrab) phab ntsa tuab cov yeeb nkab ntawm cov duab cylindrical, ua rau seamless, welded (ntev lossis kauv), lossis hluav taws xob -kuj-welded (ERW) cov ntaub ntawv. Nws siv rau cov yeeb nkab piles siv hauv kev tsim kho thiab engineering tej yaam num rau kev sib sib zog nqus foundation daim ntaub ntawv.
Qib 2: Qhov no yog ib qho ntawm cov qib uas tau teev tseg hauv ASTM A252, uas txhais cov khoom siv kho tshuab thiab tshuaj lom neeg muaj pes tsawg leeg rau cov hlau.
Cov txiaj ntsig ntawm ASTM A252 Qib 2 yog dab tsi?
Mechanical Properties:
Tensile zog: Qhov tsawg kawg nkaus tensile lub zog rau Qib 2 feem ntau yog nyob ib ncig ntawm 448 MPa (65,000 psi).
Yield zog: Qhov tsawg kawg nkaus tawm lub zog yog kwv yees li 310 MPa (45,000 psi).
Elongation: Tus qauv kuj qhia txog qhov yuav tsum tau elongation los xyuas kom meej ductility.
Dab tsi yog cov khoom sib npaug ntawm astm a252 qib 2
Khoom siv hauv tsev
Q235B (qee zaum)
Zoo sib xws: Q235B yog ib hom carbon steel qauv hauv Suav teb, muaj qee lub zog thiab zoo plasticity thiab weldability. Hauv cov ntawv thov xws li cov hauv paus hauv paus uas yuav tsum muaj lub zog tsis muaj zog tshwj xeeb, nws cov yam ntxwv ua haujlwm zoo ib yam li A252 GR2, ntsib cov kev xav tau zoo sib xws rau kev txhawb nqa hauv paus.
Qhov sib txawv: Cov tshuaj muaj pes tsawg leeg thiab qee qhov ntsuas kev ua tau zoo ntawm ob qho yuav muaj qhov sib txawv me ntsis, thiab lawv ua raws li cov qauv sib txawv. Q235B ua raws li Suav cov qauv hauv tebchaws, thaum A252 GR2 ua raws li Asmeskas cov qauv ASTM.
Cov ntaub ntawv thoob ntiaj teb
S235JR (European Standard)
Zoo sib xws: S235JR yog ib qho tsis yog - alloy structural steel nyob rau hauv European tus qauv EN 10025. Nws cov khoom siv, xws li yield zog thiab tensile zog, zoo ib yam li A252 GR2, ua ob qho tib si haum rau kev tsim cov khoom siv. Nws tuaj yeem siv los ua cov khoom siv zoo sib xws hauv qee tus choj, lub tsev, thiab lwm yam kev tsim vaj tsev hauv paus.
Qhov txawv: Cov kev sim thiab qee qhov kev xav tau zoo yuav txawv raws li cov qauv sib txawv. Hauv cov ntawv thov tshwj xeeb, kev ntsuas yuav tsum tau ua raws li cov qauv kev tsim vaj tsev thiab cov kev xav tau.
Tensile Requirements
Xam qhov tsawg kawg nkaus Elongation tus nqiA
A252 GR2 Yeeb Nkab Pleev Anti-Corrosion Process Workflow
| Txheej txheem txheej txheem | Cov ntsiab lus technical | Muaj nuj nqi |
|---|---|---|
| 1. Surface Pre-kev kho mob | - Grit blasting derustingSA 2.5 qib (ISO 8501), nto roughness 40-80μm - Cov kuab tshuaj ntxuav: Tshem cov roj, ntsev, thiab cov khoom paug |
Xyuas kom cov txheej adhesion, tiv thaiv delamination |
| 2. Anti-Corrosion Txheej Daim Ntawv Thov | Kev xaiv: | |
| a) Epoxy hmoov txheej (FBE) | - Thickness: 300-400μm - Curing: 200℃thermal curing rau daim duab ntom ntom |
Base corrosion kuj, tshuaj lom neeg / electrolyte tiv thaiv |
| b) 3PE Composite Txheej | - Qauv: FBE + Adhesive txheej + Polyethylene (PE) - Tag nrho thickness Ntau dua los yog sib npaug li 2.5mm |
Txhim khu kev cuam tshuam (rau pob zeb / ntug dej hiav txwv ib puag ncig) |
| c) Kub-Dip Galvanizing | - Zinc txheej Ntau dua lossis sib npaug rau 85μm (ISO 1461) - Kev pab them nqi tag nrho suav nrog cov welds |
Tus nqi -kev tiv thaiv zoo (ib puag ncig me me) |
| 3. Kev kho Weld | - Epoxy resin kov- rau ntawm thaj chaw weld - NDT (UT/RT) los tshem tawm cov pores/slag |
Tshem tawm cov ntsiab lus tsis muaj zog |
| 4. Kev tiv thaiv Cathodic | - Txaus siab rau tam sim noAnode txaj installation (-0.85 ~ -1.2V vs CSE) - Kev Txhaum Cai Anodes: Txuas Al / Zn alloy blocks |
Electrochemical protection (>50-xyoo kev pab cuam lub neej) |
| 5. Kev soj ntsuam zoo | - Txheej xeem: Spark test (Ntau dua lossis sib npaug ntawm 5kV), ntsuas qhov tuab - Adhesion xeem: Hla- txiav (ASTM D3359) |
Txheeb xyuas qhov tseeb ntawm txheej txheej |
