1. Txhais & Cov Qauv Ua Raws Cai
Q:ASTM A671 CC70 Chav Kawm 20 yog dab tsi?
A:
Hom: Hluav taws xob-fusion-welded carbon steel yeeb nkab tsim rauqis- kub thiab nruab nrab- kev pabcuam siab(rated rau-50 ° F / -45 ° C).
Qib CC70: Cov pa roj carbon ntau dua -manganese cov ntsiab lus (C ≤0.35%, Mn ≤1.20%) dua li CC65, muab kev txhim kho lub zog.
Chav Kawm 20: QhiaTsawg tshaj tawm lub zog ntawm 20 ksi (138 MPa)thiab standardized phab ntsa thickness / siab ntsuas.
Ntsiab StandardASTM A671, nrog ntxiv ua raws li ASME B31.3 rau cov kav dej siab.
Nco tseg: Chav Kawm 20 muab qhov sib npaug ntawm tus nqi thiab kev ua haujlwm rau cov ntawv thov nruab nrab.
2. Cov ntawv thov ib txwm
Q:Chav Kawm 20 feem ntau siv nyob qhov twg?
A:
Tub yees Systems: Ammonia / Freon pipelines nyob rau hauv industrial txias.
Roj & Roj: Tsawg-siab cryogenic hloov kab (tsis yog- tseem ceeb).
Cov nroj tsuag tshuaj: Kev thauj cov kua dej me me ntawm qhov kub thiab txias.
Lub zog tiam: Pab ua kom txias txias hauv nruab nrab 低温 ib puag ncig.
Kev cais tawm: Tsis haum rauLNG lossis kev pabcuam huab cua txias heev(yuav tsum tau CC65 qib).
3. Cov khoom vaj khoom tsev & kev xeem yuav tsum tau ua
Q:Dab tsi yog cov khoom siv tseem ceeb thiab kev xeem?
A:
Mechanical Properties:
Yield zog:≥20ksi (138 MPa).
Tensile zog:60-85 ksi (414-586 MPa).
Kev sim cuam tshuam: Xaiv tau(project-specific; Charpy V-notch at-50 ° F / -45 ° Cyog xav tau).
Tsis yog -Kev Ntsuas Kev Puas Tsuaj (NDT): Qhov chaw radiography (RT)los yogKev tshuaj xyuas qhov muag (VT)tshwj tsis yog tias siv cov cai nruj dua.
4. Sib piv nrog Lwm Cov Qib
Q:Chav Kawm 20 piv rau qib CC65 li cas (xws li Chav Kawm 70/71)?
A:
| Parameter | CC70 Chav Kawm 20 | CC65 Chav Kawm 70/71 |
|---|---|---|
| Qhov kub thiab txias | -50 ° F / -45 ° C | -65 ° F / -54 ° C |
| Yield zog | 20 ksi (138 MPa) | 70+ ksi (483+ MPa) |
| Nqi Efficiency | Siab dua (qis alloy cov ntsiab lus) | Lower (tshwj xeeb) |
Kev pauv - tawm: Class 20 yogkev lag luam ntau duarau nruab nrab 低温 daim ntawv thov tab sis tsis muaj qhov ultra- qis- kev ua haujlwm kub ntawm CC65 qib.
5. Fabrication & Welding Guidelines
Q:Dab tsi yog cov txheej txheem tseem ceeb ntawm kev tsim khoom?
A:
Vuam:
Preheat rau150-250 ° F (66-121 ° C) for thickness >1 nti (25 mm).
SivAWS E6010/E7018(tsawg-hydrogen xaiv tau rau qhov tseem ceeb welds).
Tshaj tawm -Kev kho cua sov (PWHT): Xaiv tau tshwj tsis yog tias tau teev tseg (piv txwv li, rau cov ntu tuab lossis siab ceev).
Kev tiv thaiv corrosion: Epoxy ximlos yogkub-dip galvanizingrau ib puag ncig me me.
Cov Lus Qhia Ua Raws Cai: Ib txwm txheeb xyuas qhov project- cov kev cai tshwj xeeb (piv txwv li, NDT qhov twg, PWHT) tawm tsamASTM A671-XX25thiabASME B31.3.
