BV F460 thiab BV F550 yog siab- lub zog steel phaj ntawv pov thawj los ntawm Bureau Veritas (BV) rau kev qaug zog- cov ntawv thov tseem ceeb. Qhov kev xaiv "F" yog qhov tseem ceeb, qhia txog lawv qhov kev tsim nyog rau cov khoom raug rau qhov tseem ceeb cyclic dynamic loading. Cov qib no yog tsim los rau cov khoom tseem ceeb hauv kev xav tau cov qauv hauv hiav txwv thiab sab nrauv uas muaj lub neej qaug zog zoo dua, muaj peev xwm ntes tau, thiab cov tawv nqaij tawg yog qhov tseem ceeb, xws li hnyav- nqa nkoj crane pedestals, offshore platform node pob qij txha, thiab siab - thaj chaw muaj kev ntxhov siab ntawm cov khoom tsim tawm.
Qhov txawv tseem ceeb:
Qhov tseem ceeb sib txawv yog nyob rau hauv lawv cov qib zog. BV F460 muaj qhov tsawg kawg nkaus lub zog ntawm 460 MPa, thaum BV F550 muaj qhov muaj zog ntau dua ntawm 550 MPa. Qhov no muab F550 nrog cov npoo ntau dua tiv thaiv cov txiaj ntsig zoo li qub nyob rau hauv kev ua haujlwm siab thiab siab tshaj.
Yuav kom ua tiav qhov "F" hauv chav kawm ntawv, ob qib yuav tsum ua kom tau raws li cov kev cai nruj rau kev huv huv steel (tsawg sulphur, tswj kev suav nrog), nplua -grained microstructure, thiab lav los ntawm - cov khoom tuab. Txawm li cas los xij, tau txais lub zog siab dua ntawm F550 thaum tuav cov kev qaug zog tshwj xeeb thiab cov yam ntxwv toughness yuav tsum tau tsim cov hlau alloy ntau dua. Qhov no suav nrog qhov tseeb ntxiv ntawm micro-alloying cov ntsiab lus (xws li Niobium, Vanadium) thiab feem ntau siab dua ntawm Nickel thiab Molybdenum, ua tiav raws li qhov ntsuas kub nruj-txheej txheem tswj kev ua haujlwm (TMCP) lossis quenching thiab tempering (Q&T). Yog li ntawd, BV F550 muaj qhov tshwj xeeb siab dua carbon sib npaug (Ceq) thiab tawg rhiab qhov ntsuas piv rau F460. Qhov no ua rau cov fabrication ntawm F550, tshwj xeeb tshaj yog vuam, ho nyuaj thiab txwv. Nws tso cai rau kev siv cov khoom tshwj xeeb, siab{12}}tuaj yeem muab tub lim hlau, ua tib zoo tswj kev ua ntej ua ntej (feem ntau yuav tsum tau kub siab tshaj 100 degree) thiab sib cuam tshuam qhov kub thiab txias, nruj txwv ntawm cov cua sov input, thiab yuav luag txhua zaus yuav tsum tau tshaj tawm -weld heat treatment (PWHT). Kev xaiv ntawm F550 tshaj F460 yog qhov kev txiav txim siab tseem ceeb hauv engineering tau tsim los ntawm kev txheeb xyuas kev qaug zog, qhov xav tau kom muaj zog zoo li qub thiab muaj peev xwm ua rau lub neej qaug zog ntau dua qhov kev nce nqi ntawm cov khoom siv thiab cov khoom siv tsis yooj yim.
Tshuaj muaj pes tsawg leeg
|
BV F460 ntxiv Cov Tshuaj Muaj Zog Muaj Zog Muaj Zog Tempering thiab Quenching |
|||||||
|
Qib |
Cov ntsiab lus Max (%) |
||||||
|
C |
Si |
Mn |
P |
S |
Al (min) |
N |
|
|
BV F460 |
0.18 |
0.55 |
1.60 |
0.025 |
0.020 |
0.015 |
0.020 |
|
BV F550 ntxiv Cov Tshuaj Muaj Zog Muaj Zog Muaj Zog Tempering thiab Quenching |
|||||||
|
Qib |
Cov ntsiab lus Max (%) |
||||||
|
C |
Si |
Mn |
P |
S |
Al (min) |
N |
|
|
BV F550 |
0.18 |
0.55 |
1.60 |
0.025 |
0.020 |
0.015 |
0.020 |
Mechanical Property
|
BV F460 ntxiv Cov khoom muaj zog siab hauv Tempering thiab quenching |
||||||
|
Qib |
Mechanical Property |
Charpy V Impact Test |
||||
|
Yield |
Tensile |
Elongation |
Qib |
Zog 1 |
Zog 2 |
|
|
BV F460 |
Min Mpa |
Mpa |
Tsawg% |
-60 |
J |
J |
|
460 |
570-720 |
17% |
31 |
46 |
||
|
Lus Cim: Lub Zog 1 yog qhov kev ntsuas cuam tshuam, Lub Zog 2 yog qhov ntev |
||||||
|
BV F550 ntxiv Cov khoom muaj zog siab hauv Tempering thiab quenching |
||||||
|
Qib |
Mechanical Property |
Charpy V Impact Test |
||||
|
Yield |
Tensile |
Elongation |
Qib |
Zog 1 |
Zog 2 |
|
|
BV F550 |
Min Mpa |
Mpa |
Tsawg% |
-60 |
J |
J |
|
550 |
670-830 |
16% |
37 |
55 |
||
|
Lus Cim: Lub Zog 1 yog qhov kev ntsuas cuam tshuam, Lub Zog 2 yog qhov ntev |
||||||
