DNV E550 Steel Plate | NV E550 Shipbuilding Steel Plate

NV E550 steel plate, also written as DNV E550, DNV Grade E550, VL E550 (newer DNV Rules designation) or market names such as EH55 / EQ56, is the extra-high-strength hull structural steel of DNV Rules for Classification of Ships (IACS UR W16 extra-high-strength family) with 550 MPa minimum yield, 670-830 MPa tensile strength and Charpy V-notch toughness at -40°C [-40°F]. In the grade name, "E" is the toughness class, and "550" is the yield-strength level in MPa. Gangsteel, a steel plate exporter, supplies DNV NV E550 plates cut to size for shipbuilding, offshore platforms and marine structures.

Data source: Per IACS UR W16 (extra-high-strength hull structural steel) as adopted in DNV hull structural steel rules, cross-checked with live DNV E550 tables and LR EH55 / ABS EQ56 sibling pages on gangsteel.net. Official mill/certificate grade is NV E550 (VL E550). Verify the current DNV edition before ordering.

NV E550 Chemical Composition (Heat Analysis)

 

Element	C	Mn	Si	P	S	Al (acid sol.)
NV E550, %	0.20 max	1.70 max	0.10-0.55	0.030 max	0.030 max	0.015 min
Element	N	Nb	V	Ti	B	Notes
NV E550, %	0.020 max	0.02-0.05	0.04-0.10	0.02 max	0.005 max	Ni/Cu/Cr/Mo per delivery condition (N/TM/QT) in UR W16

Per IACS UR W16 / DNV extra-high-strength rules. Exact maxima for Ni, Cu, Cr and Mo depend on delivery condition (N/NR, TM or QT). Carbon equivalent / CET / Pcm limits apply by thickness and condition; confirm on the mill certificate and current rule edition.

Product Analysis (Check Analysis)

 

When product analysis is required, apply ASTM A6/A6M Table A permitted variations to the heat limits unless the element is min-only or not listed in Table A.

Element	Heat analysis limit	Product analysis (heat ± A6)
C	0.20 max	0.24 max
Mn	1.70 max	see A6 Table A vs heat upper limit
Si	0.10-0.55	0.05–0.61 (approx. A6)
P	0.030 max	0.040 max
S	0.030 max	0.040 max
Al (acid sol.)	0.015 min	no A6 Table A tolerance; product value not tabulated
N	0.020 max	0.025 max (typical A6 +0.005)
Nb	0.02-0.05	0.010–0.060
V	0.04-0.10	0.030–0.110
Ti	0.02 max	0.03 max
B	0.005 max	product analysis often not applicable

Product analysis applies only when specified; for a range, results may not vary both above and below it.

NV E550 Mechanical Properties

 

Grade	Yield strength, min	Tensile strength	Elongation, min
NV E550	550 MPa [80 ksi]	670-830 MPa [97-120 ksi]	16%

Per IACS UR W16 / DNV rules (common t≤50 mm values shown on live DNV grade pages). Yield may step down for thicker plates per UR W16; confirm thickness-dependent values on the order.

Charpy V-Notch Impact Requirements (-40°C [-40°F])

 

Thickness	Test temperature	Longitudinal, avg min	Transverse, avg min
t≤50 mm	-40°C [-40°F]	55 J	37 J
50<t≤70 mm	-40°C [-40°F]	55 J	37 J
70<t≤100 mm	-40°C [-40°F]	55 J	37 J

Per IACS UR W16 / DNV extra-high-strength practice as reflected on live DNV E550 pages (same energy across the listed bands). Average of three full-size specimens; transverse values apply when required. Thicker plates by agreement.

Delivery Condition and Deoxidation

Deoxidation: Killed, fine-grain practice. Delivery condition: typically TMCP or QT for extra-high-strength plates; N/NR may apply at lower extra-high levels per rules. E-class (NV E550 / EH55) grades are supplied normalized or TMCP; as-rolled delivery is not permitted for the E toughness class. Optional extras: UT, Z15/Z25/Z35, DNV survey.

Thickness Coverage

Extra-high-strength DNV NV A/D/E/F 420-690 plates are commonly supplied from about 6 mm to 100 mm thick (thicker by agreement under UR W16). Width 1500-4000 mm and length 6000-18000 mm are typical.

Equivalent Steel Grades of NV E550

 

Society / Standard	Equivalent grade
DNV	NV E550 / VL E550 (LR EH55 / ABS EQ56)
LR (Lloyd's Register)	LR EH55 steel plate
ABS	ABS EQ56 steel plate
CCS	CCS E550 steel plate
GL	GL E550 steel plate
BV	BV E550 steel plate
NK	NK E56 steel plate
KR	KR E56 steel plate
RINA	RINA E550 steel plate

IACS societies align extra-high-strength hull grades under UR W16; naming differs (DNV E550, LR EH55, ABS EQ56). Dual certification is common when ordered that way.

FAQ about DNV E550 / NV E550 Steel Plate

What is DNV E550 (NV E550) steel plate?

It is an extra-high-strength hull structural steel under DNV Rules for Classification of Ships (IACS UR W16 extra-high-strength family), with 550 MPa minimum yield, 670-830 MPa tensile strength and Charpy toughness at -40°C [-40°F].

What does NV E550 stand for?

NV (or VL) is the DNV grade prefix. The letter E is the toughness class (Charpy at -40°C [-40°F]), and 550 is the yield-strength level in MPa. Market/LR naming often uses EH55; ABS often uses EQ56.

What is the yield strength of DNV NV E550?

Minimum 550 MPa (80 ksi), tensile 670-830 MPa (97-120 ksi), elongation about 16% min (for the common thickness range).

What is the impact test temperature for NV E550?

Charpy V-notch at -40°C [-40°F]. Typical longitudinal average minimum is 55 J (transverse 37 J) for the tabulated thickness range on this grade page.

What is the difference between NV A550, D550, E550 and F550?

Same 550 MPa strength class. Toughness class differs: A at 0°C, D at -20°C, E at -40°C, F at -60°C. Chemistry (C, P, S, Mn) is tightened for colder classes.

How does NV E550 differ from higher-strength NV A40?

NV A40 is UR W11 higher-strength (390 MPa). NV E550 is UR W16 extra-high-strength (550 MPa) with different chemistry and delivery practice (often TM/QT).

Is NV E550 the same as LR EH55 or ABS EQ56?

They are IACS counterparts in the extra-high-strength family; exact chemistry/delivery options differ by society edition. Dual certification is available when surveys are arranged.

Is DNV NV E550 weldable?

Weldable with approved procedures for extra-high-strength ship steel. Preheat, heat input and consumable matching are critical; follow the mill WPS and DNV welding requirements.

What heat treatment is required for NV E550?

Extra-high-strength grades are typically delivered TMCP or quenched and tempered (QT), sometimes normalized/normalized-rolled depending on strength level and thickness. E-class (NV E550 / EH55) grades are supplied normalized or TMCP; as-rolled delivery is not permitted for the E toughness class.

What thickness is available for DNV E550?

Common supply is about 6-100 mm (thicker by agreement under UR W16 / DNV rules), 1500-4000 mm wide and 6000-18000 mm long.

Other DNV Steel Plate Grades

DNV Grade A steel plate | DNV Grade B steel plate | DNV Grade D steel plate | DNV Grade E steel plate | DNV A32 steel plate | DNV A36 steel plate | DNV A40 steel plate | DNV D32 steel plate | DNV D36 steel plate | DNV D40 steel plate | DNV E32 steel plate | DNV E36 steel plate | DNV E40 steel plate | DNV F32 steel plate | DNV F36 steel plate | DNV F40 steel plate | DNV AH36 steel plate | DNV EH40 steel plate | DNV A420 steel plate | DNV A460 steel plate | DNV A500 steel plate | DNV A550 steel plate | DNV A620 steel plate | DNV A690 steel plate | DNV D420 steel plate | DNV D460 steel plate | DNV D500 steel plate | DNV D550 steel plate | DNV D620 steel plate | DNV D690 steel plate | DNV E420 steel plate | DNV E460 steel plate | DNV E500 steel plate | DNV E620 steel plate | DNV E690 steel plate | DNV F420 steel plate | DNV F460 steel plate | DNV F500 steel plate | DNV F550 steel plate | DNV F620 steel plate | DNV F690 steel plate

Equivalent Class Society Grades

DNV NV E550 corresponds to extra-high-strength counterparts under other IACS societies (LR EH55, ABS EQ56, etc.): LR EH55 steel plate, ABS EQ56 steel plate, CCS E550 steel plate, GL E550 steel plate, BV E550 steel plate, NK E56 steel plate, KR E56 steel plate, RINA E550 steel plate.