1. ASTM A671 CF70 Class 20 Pipe yog dab tsi?
Teb:
ASTM A671 CF70 Chav Kawm 20 yog asiab -lub zog hluav taws xob- fusion-welded (EFW) carbon steel yeeb nkabtsim rauultra- qis- kev pabcuam kub (-70℃F/-57 degree)thiabsiab -kev siv siab.
Txheem:ASTM A671 (2025 Edition, nrog rau kev txhim kho NDE).
Qib:CF70 npecarbon steel optimized rau cryogenic toughness thiab hydrogen compatibility.
Chav Kawm 20:QhiaTsawg tshaj tawm lub zog ntawm 20 ksi (138 MPa)- tseem ceeb rauLH₂ (kua hydrogen) infrastructure.
2025 Innovation:Muaj nrogembedded IoT sensorsrau tiag tiag -lub sij hawm siab/kub saib xyuas hauv cov nroj tsuag ntse.
2. Cov Khoom Siv Tseem Ceeb & Kev Ntsuas (2025 Hloov Kho)
Teb:
Tshuaj muaj pes tsawg leeg:
C Tsawg dua lossis sib npaug li 0.18%, Mn: 1.00–1.60%,S / P Tsawg dua lossis sib npaug li 0.012%(2025 stricter txwv rau hydrogen kuj).
Micro{0}} alloying:Nb/V/Ti ntxiv raunplej refinement (mandatory for thickness >1.5").
Mechanical Properties:
Tensile zog:80-110 ksi (552-758 MPa).
Charpy V-ntsis:Ntau dua lossis sib npaug li 25 ft-lb (34 J) ntawm-70℃F(ibASTM A370-2025 Cov Lus Qhia Tshwj Xeeb).
Kev Tswj Xyuas Zoo:
100% phased-array UT + DR (Digital Radiography)rau weld seams.
Hydrogen ua ntej -kev ntsuas kev them nqixav tau rau daim ntawv thov LH₂.
3. Sib piv nrog Cov Qib Sib Tw (2025 Kev Ua Lag Luam)
| Parameter | CF70 Chav Kawm 20 | CF70 Chav Kawm 13 | AISI 304L Stainless hlau |
|---|---|---|---|
| Yield zog | 20 ksg | 13 ksg | 25 ksg |
| Temp Range | -70℃F rau +750℃F | -70℃F rau +700℃F | -425℃F rau +800℃F |
| Tus nqi (2025) | 2,800–2,800–3,500/ton | 2,000-2,000-2,500/ton | $6,000+/ton |
| Zoo tshaj rau | LH₂ siab - siab piping | Nruab nrab -siab cryogenics | Corrosive cryogenic ib puag ncig |
4. Dimensions, Tolerances & Manufacturing
Teb:
Qhov Loj Loj: 14" rau 96" OD( nthuav dav raumodular hydrogen liquefaction tsheb ciav hlau).
Phab ntsa Thickness: 0.5 "mus rau 3.0"(tshiabasymmetric phab ntsa xaivrau kev tswj kev ntxhov siab thermal).
Kev kam rau ua (ASTM A671: 2025):
OD: ±0.7% (≤48") / ±1.0% (>48").
Phab ntsa:+10%/-5% (tightest hauv CF70 series).
Kev tsim tawm:
Hybrid laser -SAW vuamnrogAI-tsav kev kuaj pom qhov tsis xws luag.
Tom qab-weld cryogenic kho(-110℃F) rau kev ntxhov siab.
5. 2025 Daim ntawv thov & Kev nkag siab txog kev yuav khoom
Teb:
Txiav - Ntug Siv:
Liquid Hydrogen (LH₂) bulk thauj pipelines(tsim siab txog 1,500 psi).
Fusion reactor cryogenic kev txhawb nqa tshuab(ITER/DEMO tej yaam num).
Arctic LNG terminalsnrog -70℃F ambient resilience.
Ua raws li:
ASME B31.12-2025(Hydrogen Piping Code).
ISO 21009-3: 2025(Cryogenic piping rau hydrogen).
Cov Lus Qhia:
Lub sijhawm ua haujlwm:6-9 lub hlis vim 2025 hydrogen boom; ua ntejdual{0}} ntawv pov thawj (CF70+A420)cov neeg muab khoom.
Green Procurement: Hydrogen{0}}smelted steelcov kev xaiv txo lub neej voj voog CO₂ los ntawm 50%.
