Txheej txheem cej luam thiab Daim Ntawv Thov Tseem Ceeb
A335 P2yog seamless ferritic alloy -steel yeeb nkab npaj rau siab - kub kev pab cuam. Nws yog feem ntau hu ua"Chrome-Moly"yeeb nkab vim nws cov ntsiab lus tseem ceeb alloying: Chromium thiab Molybdenum.
Nws thawj daim ntawv thov yog nyob rau hauvboiler systems, superheaters, thiab kub exchangersnyob rau hauv cov chaw tsim hluav taws xob, refineries, thiab lwm qhov chaw muaj kev lag luam uas cov kav dej yuav tsum tiv taus siab sab hauv thiab kub.
A335 P2 Chemical Composition (raws li ASTM A335 / A335M Standard)
Cov muaj pes tsawg leeg yog qhov tseem ceeb rau kev ua tiav qhov xav tau siab - qhov kub thiab txias thiab corrosion kuj.
| Lub ntsiab | Kev sib xyaw (%) |
|---|---|
| Cov pa roj carbon (C) | 0.10 - 0.20 |
| Manganese (Mn) | 0.30 - 0.61 |
| Phosphorus (P) | 0.025 max |
| Sulfur (S) | 0.025 max |
| Silicon (Si) | 0.10 - 0.30 |
| Chromium (Cr) | 0.50 - 0.81 |
| Molybdenum (hli) | 0.44 - 0.65 |
Vim li cas cov ntsiab lus tseem ceeb:
Chromium (Cr):Txhim khu kev tiv thaiv oxidation (scaling) thiab corrosion, tshwj xeeb tshaj yog thaum kub kub. Nws kuj ua kom muaj zog.
Molybdenum (Molybdenum):Qhov tseem ceeb nce lub zog ntawm qhov kub thiab txias thiab txhim kho kev tiv thaiv kom nkag tau (qhov nyiam ntawm cov khoom siv kom deform qeeb hauv qhov kev ntxhov siab tas li ntawm qhov kub siab).
A335 P2 Mechanical Properties
Cov kav dej yog muab rau hauvannealed los yog normalized thiab temperedtshav kub- kho mob kom ua tau zoo microstructure thiab txhua yam khoom.
| Khoom | Tus nqi |
|---|---|
| Tensile zog | 415 MPa (60,000 psi) min |
| Yield zog | 205 MPa (30,000 psi) min |
| Elongation | Nws txawv nrog phab ntsa tuab, tab sis feem ntau tsawg kawg yog 30% hauv 2 ntiv tes. |
Cov yam ntxwv tseem ceeb thiab qhov zoo
Zoo heev High -Temperature Strength:Qhov laj thawj tseem ceeb rau nws siv. Nws tuav nws cov qauv kev ncaj ncees thiab lub zog ntawm qhov kub thiab txias qhov twg carbon steel yuav tsis muaj zog sai.
Zoo Creep Resistance:Cov ntsiab lus molybdenum yog qhov tseem ceeb rau kev tiv thaiv ntev - lub sij hawm deformation nyob rau hauv kev ntxhov siab nyob rau hauv qhov kub thiab txias, uas yog ib tug thawj tsis ua hauj lwm hom nyob rau hauv boiler raj.
Txhim kho Oxidation Resistance:Cov ntsiab lus chromium muab cov txheej txheem tiv thaiv oxide, txo cov khoom poob vim qhov ntsuas hauv chav thiab cov pa hluav taws xob.
Weldability:P2 steel muaj qhov zoo weldability, tab sis nws yuav tsum tau ua ntej- cua sov thiab tom qab-weld heat treatment (PWHT) ua raws li cov txheej txheem nruj los tiv thaiv kev tawg thiab kho cov khoom siv hauv tshav kub- thaj chaw cuam tshuam (HAZ).
Common Specifications thiab Forms
Kev tswj hwm tus qauv: ASTM A335 / A335M- Txheem Specification rau Seamless Ferritic Alloy-Steel Pipe rau High-Tsev Kev Pabcuam.
Yeeb Nkab Txheej Txheem:Seamless (yuav tsum tau rau qhov specification).
Qhov ntau thiab tsawg:Muaj nyob rau hauv ib tug ntau yam ntawm sab nraud diameters thiab phab ntsa thicknesses (cov sij hawm), feem ntau los ntawm NPS 1/4 rau NPS 24.
Sib piv nrog Lwm Qib
Nws yog qhov pab tau kom pom qhov twg P2 haum nyob rau hauv dav dav A335 tsev neeg:
| Qib | Lub Npe | Ntsiab Alloying Elements | Hom Siv Case |
|---|---|---|---|
| A335 P1 | Cov pa roj carbon-Moly | ~ 0.50% Mo | Nruab nrab kub, zoo dua cov pa roj carbon steel. |
| A335 P2 | 1/2 Chrome-Moly | 0.5-0.8% Cr, 0.5% Mo | Qib no. Zoo sib npaug ntawm tus nqi thiab kev ua haujlwm rau ntau daim ntawv thov boiler. |
| A335 P11 | 1-1/4 Chrome-Moly | 1.00% Cr, 0.5% Mo | Kub thiab siab tshaj P2. |
| A335 P22 | 2-1/4 Chrome-Moly | 2.25% Cr, 1.00% Mo | Muaj ntau heev rau siab -siab cov kab thiab headers. |
| A335 P5/P9 | 5Cr/9Cr-Moly | 5% lossis 9% Cr, ~ 1% Mo | Superior oxidation kuj rau siab heev - qhov kub thiab txias zoo li superheaters. |
Cov ntsiab lus tseem ceeb rau kev siv
Kev kho cua sov:Nco ntsoov xyuas cov yeeb nkab tau muab tso rau hauv cov cua sov kom zoo- kho mob (annealed lossis normalized thiab tempered).
Cov txheej txheem vuam:Kev ua raws li cov txheej txheem vuam tsim nyog, suav nrog cov hlau muab tub lim kom raug (feem ntau ER80S-B2 lossis E8018-B2), ua ntej- cua sov, thiab kev kho cua sov tom qab vuam (PWHT), yogtseem ceeb heevkom tsis txhob muaj kev pabcuam tsis ua haujlwm.
Kev Ua Raws Cai:Nws siv yog tswj hwm los ntawm kev tsim kho thiab kev ua haujlwm raws li ASME Boiler thiab Pressure Vessel Code (BPVC).
Hauv cov ntsiab lus,ASTM A335 P2 yog cov yeeb nkab ua haujlwm hlauuas muab tus nqi -kev daws teeb meem zoo rau siab- qhov kub thiab txias, siab - cov kav dej siab hauv boilers thiab lwm yam khoom siv hluav taws xob tsim hluav taws xob, muab kev ua haujlwm tseem ceeb ntawm cov pa roj carbon steel.
