Txheej txheem cej luam
12 CrMoGyog achromium-molybdenum (Cr-Mo) alloy hlautshwj xeeb tsim los rau siab - qhov kub thiab txias kev pab cuam, feem ntau nyob rau hauv fais fab nroj tsuag boilers thiab siab hlab ntsha. Lub "G" hauv nws lub npe sawv cev rau "Boiler" (los ntawm Suav tus qauv "Guolu"), qhia txog nws txoj kev siv.
Nws muaj kev sib xyaw ua ke zoo heev ntawm lub zog, weldability, thiab tsis kam mus rau creep (deformation nyob rau hauv kev ntxhov siab ntawm qhov kub thiab txias) piv rau cov pa roj carbon steel.
1. Cov yam ntxwv tseem ceeb & cov cuab yeej
Siab -Tsub Muaj Zog:Tuav lub zog zoo txhua yam thiab kev ua haujlwm zoo ntawm qhov kub txog li 580℃(1076℃F).
Creep Resistance:Nws lub ntsiab kom zoo dua. Nws tiv taus qhov qeeb, tsis tu ncua deformation uas tuaj yeem tshwm sim hauv cov hlau nyob rau hauv qhov kev ntxhov siab tas li ntawm qhov kub thiab txias, uas yog qhov tseem ceeb rau boiler hlab.
Zoo Oxidation Resistance:Cov ntsiab lus chromium muab kev txhim kho kev tiv thaiv rau scaling (oxidation) hauv chav ib puag ncig piv rau carbon steels.
Zoo Weldability:Nws tuaj yeem nkag tau yooj yim welded siv cov tswv yim sib txawv, txawm tias ua ntej - cua sov thiab tom qab -weld heat treatment (PWHT) feem ntau yuav tsum tau tiv thaiv kev tawg thiab kho cov microstructure.
Toughness thiab Ductility:Muab qhov sib npaug zoo ntawm lub zog thiab muaj peev xwm deform yam tsis muaj kev tawg.
2. Chemical Composition (Hloov % los ntawm qhov hnyav)
Cov muaj pes tsawg leeg yog nruj tswj los ntawm cov qauv. Ntawm no yog ib tug raug ntau yam raws li tus qauv Suavwb 5310:
| Element | Cov ntsiab lus (%) | Lub luag haujlwm ntawm Element |
|---|---|---|
| Cov pa roj carbon (C) | 0.08 - 0.15 | Muab qhov yooj yim zog thiab hardness. |
| Silicon (Si) | 0.17 - 0.37 | Deoxidizer thaum lub sij hawm steelmaking, txhim kho lub zog. |
| Manganese (Mn) | 0.40 - 0.70 | Ua kom muaj zog thiab hardenability. |
| Chromium (Cr) | 0.40 - 0.70 | Txhim kho siab -kub lub zog, nkag siab, thiab oxidation kuj. |
| Molybdenum (hli) | 0.40 - 0.55 | Qhov tseem ceeb txhim khu lub zog ntawm qhov kub thiab txias thiab creep kuj. |
| Phosphorus (P) | Tsawg dua lossis sib npaug li 0.025 | impurity; khaws cia kom tsawg los tiv thaiv embrittlement. |
| Sulfur (S) | Tsawg dua lossis sib npaug li 0.015 | impurity; khaws cia qis los txhim kho ductility thiab weldability. |
3. Mechanical Properties
Mechanical zog yog teev nyob rau hauv chav tsev kub. Qhov tsawg kawg nkaus yuav tsum tau rau ib GB 5310 feem ntau yog:
| Khoom | Tus nqi |
|---|---|
| Yield zog (Rp0.2) | Ntau dua lossis sib npaug rau 205 MPa (Ntau dua lossis sib npaug rau 30,000 psi) |
| Tensile zog (Rm) | 415 - 560 MPa (60, 000 - 81,000 psi) |
| Elongation (A) | Ntau dua lossis sib npaug li 21% |
Nco tseg:Ntawm qhov kub siab, qhov tseem ceeb ntawm lub zog (piv txwv li, tso cai rau kev ntxhov siab) yog muab los ntawm cov lej ntawm cov khoom siv thiab yog qhov qis dua qhov ntsuas kub ntawm chav tsev.
4. Kev siv ntau
12CrMoG kav tsuas yog siv nyob rau hauv siab - kub thiab siab - ib puag ncig siab:
Superheater Tubes:Qhov twg saturated chav yog ntxiv rhuab mus ua superheated chav.
Reheater Tubes:Qhov twg cov pa los ntawm lub siab - siab turbine raug xa rov qab mus rau lub boiler kom reheated ua ntej nkag mus rau nruab nrab / qis- siab turbines.
Siab -Tub kub taub hau thiab chav kav dej:Cov kav dej tseem ceeb uas nqa cov chav superheated.
Boiler Pressure Parts:Ntau lwm yam khoom nyob rau hauv lub chaw nres tsheb fais fab boiler uas ua haujlwm ntawm qhov kub siab.
5. Cov qauv tsim nyog
GB 5310: "Seamless steel raj rau kev kub siab boiler"(Tus qauv Suav tseem ceeb uas qhia txog 12CrMoG).
ASTM A335 / ASME SA335 Cov Lus Qhia:Qhov no yog qhov sib npaug US tus qauv, qhov twg qib sib piv yogP2.
Qauv TSIS MUAJ: DIN 17175Tus qauv German, qhov twg qib zoo sib xws13 CrMo44.
TS EN 10216-2:Cov txheej txheem European, qhov twg qib zoo sib xws13CrMo4-5.
6. Kev tsim khoom thiab kev ua haujlwm
Kev tsim khoom:Feem ntau manufactured liseamless kavlos ntawm cov txheej txheem xws li kub extrusion los yog tho los xyuas kom meej homogeneity thiab lub zog nyob rau hauv siab.
Kev kho cua sov:Muab tso rau hauvnormalized thiab tempered (N&T)mob. Qhov kev kho cua sov no optimizes microstructure (feem ntau yog ib qho zoo bainite) kom ua tiav kev sib xyaw ua ke zoo tshaj plaws ntawm lub zog, toughness, thiab creep resistance.
Vuam:Yuav tsum tau ceev faj cov txheej txheem.
Ua ntej-heat:~ 150-250℃(300-480℃F) raug pom zoo.
Tshaj tawm -Weld Heat Treatment (PWHT):Yuav tsum tau. Ua ntawm ~ 650-680℃(1200-1250℃F) txhawm rau txo qis kev ntxhov siab thiab kub siab rau thaj tsam kub ntxhov (HAZ).
Sib piv nrog lwm cov Boiler Steels
| Qib Steel | Hom | Ntsiab Feature | Hom Max Siv Temp |
|---|---|---|---|
| 20G | Carbon Steel | Economic, zoo zog | ~ 450℃(842℃F) |
| 12 CrMoG | Tsawg Cr-Mo | Zoo creep zog | ~ 580℃(1076℃F) |
| 15 CrMoG | Tsawg Cr-Mo | Siab dua Cr rau oxidation zoo dua | ~ 550℃(1022℃F) |
| 12Cr1MoVG | Cr-Mo-V | Vanadium ntxiv zog creep zoo | ~ 590℃(1094℃F) |
| T/P91, T/P92 | Siab Cr-Mo | Advanced siab -lub zog creep- steels resistant | ~ 650℃(1202℃F) |
Xaus
12 CrMoGyog ib qho tseem ceeb thiab txhim khu kev qha workhorse khoom nyob rau hauv thermal fais fab kev lag luam. Nws sawv cev rau theem tseem ceeb ntawm cov pa roj carbon steel, muab qhov tsim nyog nkag siab thiab siab - qhov kub thiab txias zog rau ntau ntu ntawm lub boiler kev khiav hauj lwm ntawm qhov nruab nrab mus rau qhov siab siab. Nws zoo - nkag siab txog cov khoom thiab tsim cov vuam thiab cov txheej txheem tsim ua rau nws xaiv rau cov kws ua haujlwm.
