LR DH50 steel phaj vs LR DH40 steel phaj - Kev Paub

LR DH40 yog lub siab - lub zog shipbuilding steel phaj ntawv pov thawj los ntawm Lloyd's Register (LR) rau marine thiab offshore daim ntaub ntawv. Qhov kev xaiv "DH" qhia tias nws yog qib siab dua - qib zog nrog kev cuam tshuam toughness kuaj ntawm -20 ° C. Nws muaj qhov tsawg kawg nkaus yield zog ntawm 390 MPa thiab tensile lub zog ntawm 510 mus rau 660 MPa, nrog tsawg kawg elongation ntawm 20%. Kev cuam tshuam lub zog xav tau ntawm -20 ° C yog yam tsawg kawg 26J (transverse) lossis 39J (ntev) rau thicknesses txog 50 hli. Cov tshuaj muaj pes tsawg leeg nta carbon ≤0.18% thiab manganese 0.90-1.60%. Qib no feem ntau yog muab rau hauv qhov qub, quenched thiab tempered, lossis TMCP cov xwm txheej. Nws yog dav siv los tsim cov nkoj loj xws li cov neeg nqa khoom loj, cov roj tankers, thiab cov chaw tawm ntug dej hiav txwv.

LR DH50 yog ib qho ntxiv - siab - lub zog marine steel phaj kuj tau ntawv pov thawj los ntawm Lloyd's Register (LR) nrog rau kev cuam tshuam toughness kuaj ntawm -20 ° C. Qhov "50" qhia txog qhov tsawg kawg nkaus lub zog ntawm 500 MPa thiab lub zog tensile xws li 610 txog 770 MPa, nrog qhov tsawg kawg nkaus elongation ntawm 18% rau thicknesses txog 100 hli. Kev cuam tshuam lub zog yuav tsum muaj tsawg kawg yog 33J (transverse) lossis 50J (ntev) ntawm -20 ° C. Cov tshuaj muaj pes tsawg leeg nta carbon ≤0.20% thiab manganese ≤1.70%, nrog microalloying cov ntsiab lus suav nrog Nb, V, thiab Ti rau cov khoom txhim kho. Qib no yuav tsum tau tswj kev ua haujlwm thiab feem ntau yog muab rau hauv cov xwm txheej zoo li qub. Nws yog tsim los rau ntau qhov kev xav tau ntawm cov qauv tsim hauv nkoj tsim thiab offshore platforms xav tau lub zog zoo dua.

Ob leeg LR DH40 thiab LR DH50 yog LR- ntawv pov thawj siab - lub zog marine steels nrog rau kev cuam tshuam toughness kuaj ntawm -20 ° C, kom ntseeg tau tias kev ua tau zoo hauv cov dej hiav txwv txias. Lawv qhov sib txawv tseem ceeb nyob rau hauv lub zog theem: DH40 muaj qhov tsawg kawg nkaus tawm lub zog ntawm 390 MPa nrog tensile lub zog ntawm 510-660 MPa, haum rau dav dav-lub zog hull kev tsim kho thiab offshore lug, thaum DH50 muab ib tug siab dua qhov tsawg kawg nkaus yield zog ntawm 500 MPa nrog tensile zog-7b mus txog 701 daim ntaub ntawv. xav tau lub zog zoo dua. Ob qib tshwj xeeb tswj cov tshuaj lom neeg muaj pes tsawg leeg thiab tswj kom zoo weldability rau qhov tseem ceeb marine kev pab cuam, nrog DH50 yuav tsum tau ntau meej alloying kom ua tiav nws cov cuab yeej kho kom zoo.

Tshuaj muaj pes tsawg leeg

LR DH40 siab zog tshuaj muaj pes tsawg leeg
Qib	Cov ntsiab lus Max (%)
Qib	C	Si	Mn	P	S	Al	N
LR DH40	0.18	0.05	0.9-1.6	0.035	0.035	0.015
	Nb	V	Ti	Cu	Cr	Ni	Mo
	0.02-0.05	0.03-0.10	0.02	0.35	0.20	0.40	0.08

LR DH50 ntxiv muaj zog Chemical Composition
Qib	Cov ntsiab lus Max (%)
Qib	C	Si	Mn	P	S	Al	N
LR DH 50	0.20	0.55	1.70	0.030	0.030	0.015	0.020
	Nb	V	Ti	Cu	Cr	Ni	Mo
	0.02-0.05	0.03-0.10	0.02

Mechanical Property

LR DH40 siab zog khoom
Qib		Mechanical Property			Charpy V Impact Test
Qib	Thickness	Yield	Tensile	Elongation	Qib	Zog 1	Zog 2
LR DH40	mm	Min Mpa	Mpa	Tsawg%	-20	J	J
	t≤50	390	510-650	20%		26	39
	50 t 70	390	510-650	20%		31	46
	70＜t≤100	390	510-650	20%		37	55
Lus Cim: Lub Zog 1 yog qhov kev ntsuas cuam tshuam, Lub Zog 2 yog qhov ntev

LR DH50 muaj zog muaj zog ntxiv
Qib		Mechanical Property			Charpy V Impact Test
Qib	Thickness	Yield	Tensile	Elongation	Qib	Zog 1	Zog 2
LR DH 50	mm	Min Mpa	Mpa	Tsawg%	-20	J	J
	t≤50	500	610-770	18%		33	50
	50 t 70	500	610-770	18%		33	50
	70＜t≤100	500	610-770	18%		33	50
Lus Cim: Lub Zog 1 yog qhov kev ntsuas cuam tshuam, Lub Zog 2 yog qhov ntev