ASTM A691 1.25Cr steel yeeb nkabpoob rau hauv qeb ntawmqis- alloy chromium-molybdenum steel. Nws cov tshuaj muaj pes tsawg leeg suav nrogmolybdenumntxiv rau kwv yees li1.25% chrome. Qhov no alloy formulationtxhim kho cov yeeb nkab lub zog thiab oxidation kuj nyob rau hauv siab - qhov kub thiab txias. Qhov sib ntxiv ntawm chromiumho txhim kho corrosion kuj, tshwj xeeb tshaj yog tawm tsamoxidation thiab sulfidation corrosion ntawm siab kub, thaum molybdenumntxiv dag zog rau siab -kub kev ua tau zoo thiab nkag tau yooj yim. Kev tswj xyuas meej ntawm carbon, manganese, silicon, thiab lwm yamoptimizes cov khoom siv tag nrho cov khoom.
Dab tsi yog A 691 1.25 cr sib npaug
ASTM A691 1-1/4CR sib npaug rau ASTM A335 P11 yeeb nkab, qee zaum kuj hu ua ASTM A691 Qib 11 yeeb nkab.
A691 1.25Cr vs. A335 P11
| Feature | A691 1.25Cr (GR.1-1/4Cr CL22) | A335 P11 |
|---|---|---|
| Txuj | Siab - siab welded steel yeeb nkab txheem (ERW / SAW welded yeeb nkab) | Siab -kub seamless steel yeeb nkab txheem |
| Kev tsim khoom | Ncaj- seam vuam (HF vuam / submerged arc vuam) | Kub-rolled/cold- kos seamless forming |
| Tshuaj muaj pes tsawg leeg | Cr: 1.00-1.50% Mov: 0.44-0.65% |
Cr: 1.00-1.50% Mov: 0.44-0.65%(Faj seeb: Zoo sib xws) |
| Mechanical Properties | Tensile zog Ntau dua los yog sib npaug rau 585 MPa Yield zog Ntau dua los yog sib npaug rau 415 MPa |
Tensile zog Ntau dua los yog sib npaug rau 415 MPa Yield zog Ntau tshaj los yog sib npaug rau 205 MPa |
| Max kub | Tsawg dua los yog sib npaug li 540℃(tom qab kev tshaj tawm -weld heat treatment) | Tsawg dua lossis sib npaug li 593℃(siab tshaj -kub tsis kam rau seamless yeeb nkab) |
| Tej kev siv | Roj/gas pipelines, nruab nrab -kub siab cov hlab ntsha | Fais fab nroj tsuag boiler raj, siab -kub kab |
| Kev kho cua sov | Yuav tsum tau tshaj tawm -weld stress relief (PWHT) | Normalizing + tempering (tsis muaj kev ntxhov siab hauv cov yeeb nkab seamless) |
| H₂S Corrosion Resistance | Zoo heev (nrog cov khoom siv vuam sib xws) | Zoo (tsis muaj vuam- cuam tshuam tsis muaj zog) |
ASTM A691 Yeeb Nkab Tensile Daim Ntawv Qhia
| Qib | Tensile (MPa) | Tawm tswv yim (MPa) | Elong. (50 hli) | Reduc'n ntawm Cheeb Tsam * |
|---|---|---|---|---|
| 1 CR | 380 – 550 | 230 feeb | 22% min | – |
| 1-1/4 CR | 415 – 585 | 240 feeb | 22% min | – |
| 2-1 / 4CR, 5CR, 9CR | 415 – 585 | 205 feeb | 18% min | 40% min |
| 91 | 415 – 585 | 205 feeb | 18% min | 40% min |
Tshuaj ntsuam xyuas ntawm ASTM A691 Khoom
| 1 CR | 1-1/4 CR | 2-1/4 CR | 5 CR | 9 ib CR | 91 | |
| C | 0.05-0.17 | 0.05-0.17 | 0.05-0.15 | 0.15 | 0.15 | 0.08-0.12 |
| Mn | 0.40-0.65 | 0.40-0.65 | 0.30-0.60 | 0.30-0.60 | 0.30-0.60 | 0.30-0.60 |
| P | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.020 |
| S | 0.025 | 0.025 | 0.025 | 0.025 | 0.025 | 0.010 |
| Si | 0.15-0.40 | 0.50-0.80 | 0.50 | 0.50 | 1.00 | 0.20-0.50 |
| Cr | 0.80-1.15 | 1.00-1.50 | 2.00-2.50 | 4.00-6.00 | 8.00-10.00 | 8.00-9.50 |
| Mo | 0.45-0.60 | 0.45-0.65 | 0.90-1.10 | 0.45-0.65 | 0.90-1.10 | 0.85-1.05 |
| V | – | – | – | – | 0.04 | 0.18-0.25 |
ASME SA691 EFW Pipe Test thiab tshuaj xyuas
Txhawm rau kom ntseeg tau qhov zoo ntawm cov kav dej welded, stringent non-kev kuaj kev puas tsuaj (NDT) yuav tsum tau ua thaum lub sijhawm tsim khoom, suav nrog:
Kev Ntsuas Ultrasonic (UT): txhawm rau txheeb xyuas qhov tsis xws luag hauv welds thiab cov khoom siv hauv paus.
Radiographic Testing (RT): Tshawb xyuas qhov zoo ntawm vuam.
Eddy Current Testing (ET): txhawm rau txheeb xyuas qhov chaw thiab nyob ze - deg defects.
Kev Ntsuas Hydrostatic: txhawm rau txheeb xyuas qhov siab -cov kabmob muaj peev xwm ntawm cov kav dej.
ASME SA691 EFW Yeeb Nkab Hoobkas
