DNV A32

DNV A32 DNV A32 DNV A32

DNV A32 shipbuilding steel plate and sheet

DNV A32 Steel Description:
The steel for shipbuilding and oil platform---A32, is the high tensile strength steel.
DNV A32 is the Hull structural steel,with it's good toughness properties, higher strength,strong corrosion-resistance,the processing properties,and welding properties.

DNV A32 Steel Application :
DNV A32 steel can be used in the manufacture of the ocean ship's hull structure whose weight is above 10000 tons. A32 with high strength, good toughness low temperature impact , excellent weldability characteristics, is a kind of high strength ship's hull structure plate. So DNV A32 is used to manufacture medium-sized ocean, coastal and river trade area ship's hull structure.

DNV A32 Steel chemical composition by [%]:

Grade	C max	Si max	Mn	P max	S max	Als min	Ti max	Cu max	Cr max	Ni max	Mo max
DNV A32	0.18	0.50	0.90-1.60	0.035	0.035	0.015	0.02	0.35	0.20	0.40	0.08

Note: Generally speaking CE will be ≤ 0.40%. If the delivery condition is TMPC, the CE will be : ≤ 0.36% (thickness ≤ 50mm),≤0.38%( when the thickness >50-100).
Ceq% =(C+Mn)/6+(Cr+Mo+V)/5+(Ni+Cu)/15.

As for A32, if the thickness is under 12.5mm, the minimum Mn is about 0.7%. Besides, aluminum, niobium or vanadium in which one or several elements of grain refinement elements should be added to A32 Steel.

DNV A32 Steel Mechanical properties:

Grade	Rm (MPa)	Re(MPa) min	A% min	Akv/J min
DNV A32	440-570	315	22	E.T °C	Thickness (mm)
				0	≤ 50		>50-70		>70-100
					L	C	L	C	L	C
					31	22	38	26	46	31

Note: In the list , Rm: .tensile strength,Re: Yield strength,A%: elongation, E.T: experimental temperature,L: lengthways, C: crosswise.

Because this steel contains a small amount of V, Ti, Nb and other elements of grain refinement, and in order to reduce the hardening tendency of cracks to prevent cold(ing) crack, the use of welding wire energy may be more.

DNV A32 Steel Delivery state:

Grade	Fine grains elements	category	The thickness of steel
			≤ 12	>12.5-20	>20-25	>25-35	>35-50	>50-100
DNV A32	Nb+V or V	Plate/ sheet	A(50)	N(50),CR(50),TM(50)				N(50),CR(25),TM(50)
		Profile steel		N(50),CR(50),TM(50),AR*(25)				-
	Al or Al+Ti	Plate/ sheet	A(50)		AR*(25)		-
					N(50),CR(50),TM(50)			N(50),CR(25),TM(50)
		Profile steel	A(50)	N(50),CR(50),TM(50),AR*(25)				-

Note: 1. delivery condition: A =Any ; N=Normalized ; CR=Control Rolled ; TM=TMPC, Temperature - deformation control rolling; AR*= Can be hot rolled with the agreement of Classification Society ; CR*=Can be control rolled with the agreement of Classification Society .
2. The Figure in the ( ) means the sampling volume to do the impact test, the unit is Ton.(-) means without impact test.

Contrast in the different standard

ASTM A131M	TOCT 5521	JIS G3106	BS LR	GB712
AH32	A32	SM490B SM490C	AH32	A32

Shipbuilding steel,generally speaking,a hull structure steel , is to manufacture hull as the requirements of register of shipping. Shipbuilding steel includes four grades,that is A,B,C,D. Grade A means impact test at 20°C; Grade B is impact test at 0°C; Grade C means impact test at -20°C; Grade D is impact test at -40°C. DNV A32 shipbuilding plate has low alloy content, grain refinement elements like V, Ti, Nb, etc. Welding performance is superior. Preheating before welding is generally not proceeded, but it is done if it is at a low temperature or super thickness of structural components is welded, that is , it needs to take preheating measures.

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