Txheej txheem cej luam
A335 P122yog aSeamless Ferritic Alloy-Steel Pipenpaj rausiab -kev pabcuam kub. Qhov kev xaiv "P122" yog hais txog cov tshuaj muaj pes tsawg leeg thiab cov khoom siv kho tshuab tsim los ntawm ASTM (American Society for Testing and Materials).
Nws lub ntsiab siv yog nyob rau hauvlub zog tsim boilers, tshwj xeeb hauv cov ntu uas ua haujlwm ntawm qhov kub thiab txias heev, xws li:
Superheaters
Reheaters
Main chav kab
Kub reheat kab
Cov yam ntxwv tseem ceeb
1. Tshuaj muaj pes tsawg leeg
Qib "P122" yog ib qho niaj hnub, qib siab chromium hlau. Nws cov ntsiab lus tseem ceeb alloying yog:
Chromium (Cr): ~ 10.5-12.5%- Muab kev tiv thaiv zoo heev rau oxidation (scaling) thiab corrosion ntawm qhov kub thiab txias.
Tungsten (W): 1.5-2.5%- Ib qho tseem ceeb ntxiv dag zog uas txhim kho kev nkag siab.
Cov pa roj carbon (C): 0.07-0.14%- Muab lub zog.
Molybdenum (Mo), Vanadium (V), Niobium (Nb):Cov ntsiab lus no tsim cov carbide ruaj khov uas txhim kho cov hlau zoo heevcreep zog-nws lub peev xwm los tiv thaiv deformation nyob rau hauv qhov kev ntxhov siab tas li ntawm qhov kub thiab txias nyob rau lub sijhawm ntev.
Tooj liab (Cu): 0.3-1.7%- Kuj tseem muaj zog.
Boron (B): 0.0005-0.005%- Ib qho me me tab sis tseem ceeb ntxiv uas txhim kho hardenability thiab creep zog.
Tsawg Carbon & Nitrogen Control:Kev sib xyaw ua ke ua tib zoo sib npaug los txhawb kev ruaj ntseg thiab tiv thaiv embrittlement thaum lub sijhawm ua haujlwm ntev -.
2. Mechanical Properties (ntawm chav tsev kub, raug)
Tensile zog:620 MPa (90 ksi) min
Yield zog:400 MPa (58 ksi) min
Elongation:20% min
3. Siab -Kev Ua Haujlwm Kub
Qhov no yog qhov P122 tiag tiag ci. Nws yog tsim los tuav lub zog siab thiab tiv thaiv creep ntawm qhov kub thiab txias feem ntau los ntawm580 ° txog 650 ° F (1075 ° F txog 1200 ° F). Qhov no ua rau nws haum rau feem xav tau tshaj plaws ntawm cov niaj hnub, siab -kev ua tau zoo ultrasupercritical (USC) fais fab nroj tsuag.
Sib piv nrog lwm cov Boiler Tube Qib Qib
| Feature | A335 P122 | A335 P91 (Ntau dua) | A335 P22 (Tib neeg) | A106 B / C (Carbon Steel) |
|---|---|---|---|---|
| Kev Pabcuam Temp | Siab heev (Txog ~ 650 degree) | Siab (txog ~ 600 degree) | Nruab nrab (Txog ~ 550 degree) | Tsawg (txog ~ 425 degree) |
| Ntsiab Alloy | 11% Cr, W, Cu, B | 9% Cr, Mo, V, Nb | 2.25% Cr, 1% Mo | Cov pa roj carbon, manganese |
| Lub zog | Siab tshaj | Siab heev | Zoo | Txuj |
| Nqi | Siab tshaj | Siab | Nruab nrab | qis tshaj |
| Daim ntawv thov | USC Boiler Tshooj | Supercritical boilers | General High -Temp Service | Tsawg-Tseem Chav, Dej |
Qhov zoo ntawm A335 P122
Superior Creep Strength:Tso cai rau cov phab ntsa nyias nyias rau tib lub siab ntsuas, txo qhov hnyav thiab thermal stress.
Zoo heev Oxidation Resistance:Cov ntsiab lus siab chromium tiv thaiv cov yeeb nkab los ntawm kev scaling hauv chav ib puag ncig.
Zoo Weldability:Thaum nws yuav tsum tau ua ntej- cua sov thiab tom qab-weld heat treatment (PWHT) zoo li tag nrho cov siab- alloy steels, nws feem ntau suav tias yog weldable nrog cov txheej txheem tsim nyog.
Thermal Fatigue Resistance:Ua tau zoo nyob rau hauv cyclic cua sov thiab txias tej yam kev mob.
Cov ntsiab lus tseem ceeb rau kev siv
Fabrication:Yuav tsum muaj kev tswj xyuas nruj heev thaum vuam, suav nrog kev tshwj xeeb ua ntej- cua sov thiab tom qab-weld heat treatment (PWHT) kom ua tiav qhov tseeb microstructure thiab tiv thaiv kev tawg.
Kev kho cua sov:Cov yeeb nkab yog muab rau hauvnormalized thiab temperedmob los tsim nws cov khoom siv kho kom zoo thiab microstructure.
Tus nqi:Nws yog tus hwm, siab - alloy steel thiab tseem kim dua qib zoo li P22 lossis P91.
Standards thiab Specifications
Primary Standard: ASTM A335 / A335M- Txheem Specification rau Seamless Ferritic Alloy-Steel Pipe rau High-Tsev Kev Pabcuam.
Kev kuaj:Feem ntau muab los ua kom tau raws li qhov yuav tsum tau kuaj ntxiv los ntawm:
ASTM A530/A530M- Txuj Specification rau General Requirements for Specialized Carbon and Alloy Steel Pipe.
ASME Boiler thiab Pressure Vessel Code, Tshooj I & Tshooj II.
Xaus
A335 P122 yog qhov siab -kawg, chromium- alloy steel yeeb nkab tshwj xeeb tsim los rau qhov tseem ceeb tshaj plaws, siab - kub, thiab siab - ntu siab ntawm niaj hnub fais fab nroj tsuag boilers.Nws cov chemistry siab heev muab kev sib xyaw ua ke zoo tshaj plaws ntawm kev nkag siab lub zog thiab oxidation tsis kam, ua rau nws yog ib qho khoom siv tseem ceeb rau kev txhim kho kev ua haujlwm thiab kev ntseeg siab ntawm cov tshuab hluav taws xob siab heev.
