Dab tsi yog cov khoom thiab kev siv ntawm A387 Qib 11 Chav Kawm 1 Hlau?
ASTM A387 Qib 11 Chav Kawm 2 yog tib yam chromium-molybdenum alloy muaj pes tsawg leeg tab sis nkag mus rau hauv qhov zoo li qub thiab tempered (los yog quenched thiab tempered) kev kho cua sov. Qhov no muab siab dua li - xa lub zog thiab kev ua kom zoo dua microstructure, ua rau nws tsim nyog rau cov ntawv thov uas qhov kawg PWHT los ntawm cov fabricator yog impractical los yog qhov siab dua cov cuab yeej cuab tam yog xav tau rau cov khoom tiav.
Khoom ntawm A387 Qib 11 Chav Kawm 2 Hlau:
A387 Qib 11 Chav Kawm 2 yog 1.25% Chromium-0.5% Molybdenum alloy steel phaj nkag rau hauv qhov qub thiab tempered (los yog quenched thiab tempered) kev kho cua sov. Nws cov khoom tseem ceeb muaj xws li:
Siab dua li - xa lub zog piv rau Chav Kawm 1, nrog qhov tsawg kawg nkaus tawm lub zog ntawm 240 MPa (35 ksi) vim cov txheej txheem zeb tempering.
Zoo siab - kub lub zog, nkag siab, thiab oxidation kuj (zoo ib yam li Chav Kawm 1).
Txhim kho microstructural stability los ntawm kev kho cua sov zeb, muab cov qauv tempered bainitic.
Zoo weldability, tab sis yuav tsum tau nruj preheating (~150–200° C / 300–400° F) thiab yuav tsum tau Post-Weld Thaum tshav kub kub kho (PWHT) tom qab fabrication. Tseem ceeb heev, PWHT yuav tsum tau tswj kom tsis txhob dhau -tempering thiab softening lub hauv paus hlau hauv qab lub zog uas tau teev tseg.
Txo cov khoom yooj yim rau kev ua kom kub, raws li kev rov qab los tom ntej - normalizing thiab tempering tej zaum yuav tsum tau los kho cov khoom.
Daim ntawv thov ntawm A387 Qib 11 Chav Kawm 2 Hlau:
Chav Kawm 2 tau teev tseg rau kev xav tau siab - qhov kub siab ntawm lub nkoj siv qhov twg nws qhov ua ntej - tempered mob muaj qhov zoo sib xws:
Petroleum refineries: Cov reactors tseem ceeb (piv txwv li, hydrocrackers, hydrotreaters) thiab cov hlab ntsha uas tag nrho PWHT ntawm lub rooj sib txoos zaum kawg yog qhov ua tsis tau zoo vim qhov loj me, nyuaj sab hauv, lossis tsis muaj peev xwm ua rauv.
Kev tsim hluav taws xob: Siab- cov seem boiler siab, lub tshuab nqus tsev vacuum, thiab cov khoom siv hluav taws xob uas yuav tsum tau siab dua li - tau txais lub zog.
Cov nroj tsuag tshuaj lom neeg / petrochemical: Cov cuab yeej siv hauv kev pabcuam hydrogen qhov chaw muaj kev kub ntxhov tau txais txiaj ntsig zoo.
Kho, hloov, lossis modular Cheebtsam uas yuav tsum sib phim lub zog siab dua ntawm cov cuab yeej siv hauv chav kawm 2 uas twb muaj lawm yam tsis muaj kev kho cov hlab ntsha tag nrho tom qab kev teeb tsa.
ASTM A387 Qib 11 Chav Kawm 2 Tshuaj Chemical (%)
| Qib / Khoom siv | C | Mn | Si | P (max) | S (max) | Cr | Mo |
|---|---|---|---|---|---|---|---|
| A387 Qib 11 Chav Kawm 2 (A387 Gr11 Cl2) | 0.05–0.17 dr hab | 0.40–0.65 dr hab | 0.15–0.40 dr hab | 0.035 | 0.035 | 1.00–1.50 dr hab | 0.45–0.65 Nws |
Cov ntaub ntawv tseem ceeb ntawm alloy:
Chromium (Cr): 1.00–1.50% → txhim kho oxidation & corrosion kuj
Molybdenum (Mo): 0.45-0.65% → txhim khu kev nkag siab & hydrogen tsis kam
ASTM A387 Qib 11 Chav Kawm 2 Mechanical Properties
| Qib / Khoom siv | Tensile zog | Yield zog (min) | Elongation (min) |
|---|---|---|---|
| MPa | MPa | % | |
| A387 Qib 11 Chav Kawm 2 (A387 Gr11 Cl2) | 515-690 MPa | ≥310 MPa | ≥ 18% |
Piv nrog rau Chav Kawm 1 (415–585 MPa tensile / 240 MPa tawm los),
Chav Kawm 2 muaj lub zog ntau dua, ua rau nws tsim nyog rau kev xav tau ntau dua thiab qhov kub thiab txias.
Vim li cas thiaj xaiv Class 2 Over Class 1?
Chav Kawm 2 raug xaiv thaum lub nkoj tsim khoom kawg tsis tuaj yeem ua tiav PWHT lossis thaum tus qauv tsim tshwj xeeb xav tau lub zog pib dua thiab microstructural sib xws ntawm pre- tempered phaj. Nws yog qib "kev ua tau zoo- npaj", zoo tagnrho rau cov ntawv thov uas qhov kev kho cua sov zaum kawg los ntawm tus neeg tsim khoom tsuas yog siv rau PWHT hauv zos lossis kev ntxhov siab nkaus xwb. Kev vuam zoo thiab kev tswj PWHT yog qhov tseem ceeb los khaws nws cov khoom zoo.
1. Cov xwm txheej "Class 2" cuam tshuam li cas rau cov txheej txheem vuam rau A387 Qib 11?
Lo lus nug no tshawb txog qhov ua tau zoo ntawm kev siv cov khoom siv pre-tempered Class 2, tsom rau cov kev hloov kho tshwj xeeb uas xav tau rau preheat, interpass kub, thiab Post-Weld Heat Treatment (PWHT) piv rau Chav Kawm 1.
2. Dab tsi yog qhov tsis zoo ntawm kev qhia A387 Qib 11 Chav Kawm 2 dhau Chav Kawm 1?
Cov lus nug no tshawb xyuas qhov muaj peev xwm ua lag luam tawm -tawm, xws li tus nqi siab dua, tsis yooj yim rau kev tsim kub tom qab, lossis kev pheej hmoo ntawm cov khoom puas tsuaj yog tias tsis raug PWHT raug siv rau cov cua sov uas twb muaj lawm - cov phaj kho.
3. Nyob rau hauv daim ntawv thov tshwj xeeb twg yog A387 Qib 11 Chav Kawm 2 qhov yuav tsum tau ua lossis kev xaiv?
Lo lus nug no nrhiav kev txheeb xyuas cov xwm txheej engineering uas qhov siab dua li - xa lub zog thiab ua ntej - kho microstructure ntawm Chav Kawm 2 muab qhov txiaj ntsig tseem ceeb, xws li hauv kev kho cov phiaj xwm lossis rau cov khoom siv uas lub nkoj puv PWHT ua tsis tau.
4. Yuav tsum tswj hwm dab tsi thaum lub sij hawm PWHT ntawm cov khoom siv hauv chav kawm 2 los tiv thaiv kev kub ntxhov?
Lo lus nug no hais txog qhov kev pheej hmoo tseem ceeb: ua kom ntseeg tau tias qhov yuav tsum tau tshaj tawm -weld stress relief tsis txo qis cov txiaj ntsig thiab tensile lub zog ntawm lub hauv paus hlau hauv qab qhov tsawg kawg nkaus qhov tseem ceeb rau Chav Kawm 2.
5. Qhov cuam tshuam rau qhov hnyav ntawm Chav Kawm 2 piv rau Chav Kawm 1 li cas tom qab tsim kom raug?
Cov lus nug no sib piv cov kev pabcuam zaum kawg ntawm ob chav kawm, tshuaj xyuas seb cov kev tsim khoom sib txawv ua rau muaj qhov sib txawv tseem ceeb hauv kev puas tsuaj ntawm kev ua haujlwm kub.
Tag nrho cov specification thiab cov ntsiab lus muaj nyob rau ntawm kev thov. Cov ntaub ntawv saum toj no yog muab rau kev taw qhia nkaus xwb. Rau kev tsim tshwj xeeb thov hu rau peb cov neeg ua haujlwm muag khoom.
