1. Cov ntsiab lus tseem ceeb thiab cov ntawv thov tseem ceeb
ASTM A252 (Piling Pipe Txuj): Qhia meej welded thiab seamless steel yeeb nkab pawg rau axial cuam tshuam tsis kam thiab av siab daim ntaub ntawv, xws li chaw nres nkoj foundations thiab lub ntiaj teb retention systems. Cov kev cai tseem ceeb suav nrog Tsawg dua lossis sib npaug rau 0.25% kev ua siab ntev kom ntseeg tau tias kev txhim kho precision.
ASTM A572 (Structural Steel Qauv): Npog siab -lub zog qis- alloy structural steel rau saum toj no - av load- cov ntawv thov, suav nrog cov kab hluav taws xob crane thiab lub tsev thav duab. Nws qib Gr.50 ua tiav 345 MPa yam tsawg kawg nkaus lub zog, 43% siab dua A252.
2. Kev ua tau zoo tsis tseem ceeb
| Metric | ASTM A252 (Gr.3) Txoj Cai | ASTM A572 (Gr.50) Kev ntsuas |
|---|---|---|
| Yield zog | Ntau dua lossis sib npaug li 241 MPa | Ntau dua lossis sib npaug li 345 MPa |
| Qhov yuav tsum tau muaj | Khoov tsis kam | Siab- sim sealing |
| Failure Criteria | Lub cev deformation | Pinhole leaks |
| Alloy Composition | Plain carbon steel (C Tsawg dua lossis sib npaug li 0.26%) | Tsawg- alloy (V/Nb- txhim kho) |
3. Khoom siv -Kev txiav txim siab tshwj xeeb engineering
A252 Piling Steel:
Cov txheej txheem tsim khoom: Kauv / SAW vuam rau kev cuam tshuam tsis kam
Environmental Suitability: Yuav tsum tau galvanizing rau corrosion tiv thaiv hauv av
Kev Lag Luam Tus Nqi: ~ CNY 6,000 / ton (Gr.2 qib rau kev ua kom zoo tshaj tus nqi)
A572 Cov Qauv Hlau:
Kev Ua Haujlwm Ntug: 19% siab dua tensile zog (450 MPa vs . 415 MPa)
Maintenance Advantage: Inherent huab cua tsis kam vim alloying ntsiab
Tus nqi lag luam: ~ CNY 6,500 / tuj (Q355B sib npaug muaj nyob ntawm<5% premium)
4. Daim Ntawv Thov -Txoj Kev Xaiv Cov Cai
Mandate A252 Thaum:
Kev cuam tshuam rau pawg tsav tsheb (Ntau dua lossis sib npaug rau 3-tuj rauj zog)
Siv nyob rau hauv seismic aav nrog av liquefaction txaus ntshai
Ua hauj lwm hauv marine ib puag ncig (nrog cathodic tiv thaiv)
Yuav tsum A572 Thaum twg:
Tsim ntau- zaj dab neeg tsev thav duab (cua / seismic loads)
Fabricating crane khiav kab teeb (kev qaug zog kuj tseem ceeb)
Tsim kev loj choj (dynamic load peev)
A252 Piling yeeb nkab Hoobkas
