SA691 Qib 2 1/4CR Chrome-Molybdenum Alloy Steel Boiler Pipe
Product Overview
SA691 Qib 2 1/4CR (feem ntau sau li2.25 CR) yog ib qho nruab nrab chromium-molybdenum alloy steel yeeb nkab uas tsim los rauASTM / ASME SA691specification rau hluav taws xob- fusion-welded (EFW) siab - kub thiab siab - siab piping. Qib no, nrog rau nws cov nominal muaj pes tsawg leeg ntawm 2.25% chromium thiab 1% molybdenum, yog ib qho ntawm feem ntau siv thiab ntau yam creep- zog- txhim kho ferritic steels hauv lub zog thiab txheej txheem kev lag luam. Nws muaj qhov zoo tshaj qhov sib npaug ntawm siab -kub lub zog, weldability, thiab tsis kam oxidation thiab hydrogen nres.
Cov ntawv thov tseem ceeb
Siab -Pressure Steam Piping:Cov kab hluav taws xob tseem ceeb, cov kab kub reheat, thiab superheater qhov hluav taws xob hauvsupercritical thiab subcritical fais fab nroj tsuag.
Petrochemical thiab Refining:Siab -kub hloov pauv cov kab hluav taws xob, cov kav dej kub, thiab cov kav dej hauvhydroprocessing units(zoo heev tiv thaiv hydrogen nres).
Heat Recovery Steam Generators (HRSG):Siab -cov evaporator siab thiab cov tshuab superheater.
High -Tub kub Exchangers:Tube thiab plhaub hauv kev pabcuam hnyav.
Muaj boilers:Qhov tseem ceeb siab -siab headers thiab interconnecting piping.
SA691 2.25CR Chemical Composition & Mechanical Properties Table
| Qeb | Khoom / Khoom | Specification / Tus nqi |
|---|---|---|
| Standard & Qib | Standard Designation | ASTM / ASME SA691 |
| Qib | 2 1/4CR(Compositionally sib npaug rau ASTM A335 P22 / P22 Hom 2) | |
| Tshuaj muaj pes tsawg leeg | Cov pa roj carbon (C) | 0.05 - 0.15% |
| Manganese (Mn) | 0.30 - 0.60% | |
| Phosphorus (P) | 0.025% max | |
| Sulfur (S) | 0.025% max | |
| Silicon (Si) | 0.50% max | |
| Chromium (Cr) | 2.00 - 2.50% | |
| Molybdenum (hli) | 0.87 - 1.13% | |
| Mechanical Properties | Tensile zog, min | 415 MPa (60,000 psi) |
| Yield zog (0.2% Offset), min | 205 MPa (30,000 psi) | |
| Elongation, min | Ntau dua lossis sib npaug li 20% (hauv 2 ntiv tes / 50mm) rau cov qauv phab ntsa | |
| Kev kho cua sov | Qhov xwm txheej | Normalizing thiab temperingyog tus qauv. Normalizing: 900-1000℃(1650-1830℃F); Tempering: Ntau dua lossis sib npaug rau 675℃(Ntau dua lossis sib npaug rau 1250℃F). |
| Kev tsim khoom | Hom | Hluav taws xob Fusion Welded (EFW)ua raws li kev kho cua sov tag nrho. |
Cov ntaub ntawv ua haujlwm kub siab
| Khoom | Tus nqi / Ntau | Lus Ceeb Toom / Source (Tswj) |
|---|---|---|
| Qhov siab tshaj plaws pom zoo Nruam Hlau Temp | 593℃(1100℃F) | Tus qauv txwv rau kev ua haujlwm ntev -; ASME B31.1 |
| Tso cai Stress (ntawm 538℃/ 1000℃F) | ~ 103 MPa (~ 15,000 psi) | ASME Tshooj II, Tshooj D siv tus nqi |
| Tso cai Stress (ntawm 593℃/ 1100℃F) | ~ 55 MPa (~ 8,000 psi) | Ua kom muaj zog tuav |
| Oxidation Resistance txwv | Zoo heev mus txog600℃(1110℃F) | Cov ntaub ntawv ruaj khov Cr- nplua nuj oxide txheej |
| Creep Repture Strength (100,000 teev) | ~ 100 MPantawm 538 degree | Qhov laj thawj tseem ceeb rau kev siv dav dav |
| Zoo heev Resistance Rau | Hydrogen Attack (HTHA), Sulfidation, Thermal Fatigue |
Cov yam ntxwv tseem ceeb & kev txiav txim siab
Superior High -Tsub Muaj Zog:Lub 2.25Cr-1Mo muaj pes tsawg leeg muab tshwj xeebcreep thiab rupture zognyob rau hauv qhov tseem ceeb 450-600℃(840-1110℃F) ntau yam, ua rau nws yog cov khoom ntawm kev xaiv rau lub ntsiab chav kab hauv tsoos fais fab nroj tsuag.
Resistance to Hydrogen Attack (HTHA):Qib no yogtiv taus siab heev -kub hydrogen nresntawm ib nrab siab thiab kub uas txhais los ntawm lubNelson Curves(API RP 941). Cov cuab yeej no yog qhov tseem ceeb rau nws siv hauv refinery hydroprocessing units.
Weldability thiab Fabrication:
Preheat:Yuav tsum tau, feem ntau175-250 ° F (350-480 ° F).
Tshaj tawm -Weld Heat Treatment (PWHT): Qhov tseem ceeb. Ua ntawm690-750℃(1275-1380℃F)rau tsawg kawg yog 1 teev ib nti ntawm tuab kom rov ua kom tawv thiab txo kev ntxhov siab.
Filler hlau:E9018-B3 (SMAW), ER90S-B3 (GTAW/GMAW) rau kev sib xyaw ua ke.
Yuav tsum tau ceev faj tswj ntawm interpass qhov kub thiab txias input.
Microstructural Stability:Muab nyob rau hauv qhov normalized thiab tempered mob, ua rau ib tug microstructure ntawm tempered bainite, uas ua kom lub sij hawm ntev - stability thiab creep kuj. Ntev raug nyob rau hauv lub375-575℃(700-1070℃F) ntau yamtuaj yeem ua raunpau taws embrittlement; chemistry tswj (xws li Si, Mn, P, Sn) feem ntau teev kom txo tau qhov no (xws li, "P22 Hom 2" cov cai).
Kev Ua Zoo thiab Kev Ntsuam Xyuas:
Yuav tsum xeem:Hydrostatic / NDE, tshuaj ntsuam xyuas, ntsuas nro.
Common Supplementary Tests:Ultrasonic Examination (SA791 S6), Radiographic Examination (S5), Hardness Traverses hla welds.
Advanced Requirements:Rau cov kev siv tseem ceeb,Charpy V-Kev ntsuas qhov cuam tshuamthiabcreep kuajtej zaum yuav tau teev tseg.
Economic thiab Design Advantage:Raws li EFW yeeb nkab, SA691 2.25CR muab cov nqi txuag nyiaj ntau dua seamless A335 P22 rau cov kab loj loj thiab cov phab ntsa hnyav, thaum ua tau raws li cov qauv kev ua tau zoo rau feem ntau cov ntawv thov.
Tsim, Specification, thiab Cov Lus Qhia Txog Kev Muag Khoom:
Clear Specification:Siv"SA691 Qib 2 1/4CR"los yog"SA691 Gr. 2.25CR". Rau kev txhim kho kev tiv thaiv rau temper embrittlement, qhia"Qib 2 1/4CR nrog P22 Hom 2 chemistry txwv"(Low Si, P).
Kev Ua Raws Cai:Cov khoom raug lees txais raws li ASME B31.1 (Power Piping) thiab B31.3 (Cov Txheej Txheem Piping). Ib txwm txheeb xyuas qhov txiaj ntsig kev ntxhov siab tshiab tshaj plaws los ntawm ASME Tshooj II, Ntu D.
Kev ntsuas lub neej:Rau cov nroj tsuag uas twb muaj lawm, qhov seem ntawm lub neej kev soj ntsuam feem ntau tsom rau kev puas tsuaj ntau ntxiv thiab oxidation wastage.
Cov ntaub ntawv:Xyuas kom covCertified Mill Test Report (CMTR)suav nrog cov ntaub ntawv kho cua sov tag nrho, kev tshuaj ntsuam xyuas tshuaj (tshwj xeeb tshaj yog rau cov ntsiab lus tramp), thiab cov txiaj ntsig ntawm txhua qhov kev ntsuam xyuas.
Tsis lees paub:Cov ntsiab lus no muab cov ntaub ntawv engineering dav dav. Rau tag nrho cov tsim, fabrication, thiab procurement kev ua ub no, nws yog tsim nyog los sab laj tusASTM / ASME SA691 specification, qhov cuam tshuam ntawm ASME Boiler thiab Pressure Vessel Code Sections, siv cov lej kav dej (B31.1/B31.3), thiab qhov project- cov kev cai tshwj xeeb. Cov khoom siv tuaj yeem sib txawv ntawm cov tuam ntxhab thiab cov cua sov.
