API 2W Gr50

API 2W Grade50 Offshore Steel Plate

Nearest Equivalent Grade : API 2H, EN10225 S355G7+N, S355G7+M, S355G8+N,S355G8+M

BS7191:1989  355EN, 355EMZ

Characteristic :

API 2W Grade50 is an Intermediate-Strength Structural Steel Plate, produce by Thermo-Mechanical Control Processing (TMCP)

for welded construction of offshore structures/offshore platforms. API 2W Grade 50 has a minimum yield strength of 50ksi (345MPa)

and a minimum, mid-thickness, transverse Charphy V-notch impact toughness of 41J (30 ft-lbf) at -40ºC (-40ºF)

API 2H Gr50 is an offshore steel grade which is regulated American Petroleum Institute (API) and in some cases certified by

the American Bureau of Shipbuilding (ABS).

Delivery Condition :

API 2W Grade50 Thermo-Mechanical Control Processing (TMCP) is a rolling method in which strictly controlled both reduction and

rolling temperatures with accelerated cooling control temperature in order to provide the specified mechanical properties.

Application :

API 2W Gr50 provides good toughness at the heat affected zone (HAZ), this steel grade intended primarily for use in critical heat affected areas or

sections of offshore structure projects. It is crucial to be used in tubular joints, stiffened plate construction and other intersections where portions of

the steel plates will be subjected to tension in the through-thickness (Z) direction.

API 2W Grade 50 is therefore not only an effective material for floating and rigid offshore oil and gas platforms,

thus it is crucial to be used in intersections of the structure due to the materials superior strength combined with good impact

toughness which  resistance to fatigue and lamellar tearing.

Key Features:

• Good impact resistance in heat affected zone (HAZ)
• Structural offshore grade for critical applications
• Lower carbon content for improved weldability
• Thermo-mechanically rolled for extra strength and toughness
• Resistance to lamellar tearing

Chemical Composition (wt%, max.unless indicated)

Mechanical Properties

Tensile Testing is performed transverse direction according to API 2W requirement. The minimum values are tabulated below :

Thickness, t mm [in.]	0.2% YS MPa [ksi]	UTS MPa [ksi], min.	Elongation in 50mm[2”], min.%	Elongation in 200mm (8”), min. %
t ≤ 25.4 [1.00]	345-517 [50-75]	448 [65]	23	18
t > 25.4 [1.00]	345-483 [50-70]	448 [65]	23	18

Charpy V-notch Impact Testing

Charpy V-notch Impact Testing  is performed on each plate using mid-thickness, mid-width, transverse specimens tested in accordance

with ASTM A673. The producer has the option of testing sub-size specimens to any of the combinations of specimen size, energy requirement,

and test temperature as shown below:

Specimen Size, mm	Specimen Size in.	Minimum Average Energy J [ ft-lb ]	Minimum Single Value Energy J [ ft-lb ]	Test Temperature ºC [ºF]
10 x 10	0.394 x 0.394	41 [30]	34 [25]	-40 [-40]
7.5 x 10	0.295 x 0.394	41 [30]	34 [25]	-40 [-40]
5 x 10	0.197 x 0.394	41 [30]	34 [25]	-40 [-40]
7.5 x 10	0.295 x 0.394	31 [23]	26 [19]	--46 [-50]
5 x 10	0.197 x 0.394	20 [15]	18 [13]	-62 [-80]

Chemical Composition (Heat Analysis, wt %, max. unless indicated)

C	Mn1	P	S	Si	Al Total	Ni	Cr	Mo	Cu	Ti	Cb	N2,3	B2
0.16	1.15-1.60	0.03	0.010	0.05-0.50	0.020-0.060	0.75	0.25	0.08	0.35	0.007-0.02	0.03	0.012	0.0005

1. Manganese up to 1.65 (heat analysis) is permitted at the option of the material manufacturer

2. Nitrogen and Boron shall not be intentionally added

3. Nitrogen may be 0.013% max., if titanium if 0.010 to 0.012%

TMCP Structural Steel

Thickness, t, mm [in.]	CEIIw Max	Pcm Max	CEiiw typical	Pcm Typical
≤ 40 [1.5] 40 < t ≤ 90 [1.5 < t ≤ 3.5]	0.39	0.22	0.36	0.16
	0.41	0.23	na	na

Tolerances

Thickness, width, and length tolerances for API 2W Grade 50 steel plate are in accordance with the requirements of

ASTM A6. The flatness tolerance for as-supplied product is 1⁄2 ASTM A6.

Heat-Treated (Normalized) Structural Steel

Carbon Equivalent : CEV +

Tolerances

Thickness, width, and length tolerances for API 2H Grade 50 steel plate are in accordance with the requirements of ASTM A6.

The flatness tolerance for as-supplied product is ½ ASTM A6.

Delivery Condition

API 2H Grade 50 is supplied in the normalized condition.

Fabrication and Other Recommendations

Weldability: Welding of API 2W Grade 50 shall be performed in accordance with the applicable welding code.

In the absence of a specified welding code, the following suggested minimum preheat and interpass temperatures and welding

consumables are provided. Special welding consumables and welding procedures may be required to match the base metal toughness.

Low hydrogen practices are strongly recommended, including the removal of surface moisture.

Welding Process	Thickness, mm (in)	Minimum Preheat and Interpass Temperature	Consumables
Shielded Metal Arc (SMAW)	Up to 38.1 (1.5”)	10ºC (50ºF)	AWS E7015-X, E7016-X, E7018-X
	>38.1 (1.5”) to 63.5 (2.5”)	65ºC (150ºF)
Gas Metal Arc (GMAW)	Up to 38.1 (1.5”)	10ºC (50ºF)	AWS ER70S-X
	>38.1 (1.5”) to 63.5 (2.5”)	65ºC (150ºF)
Submerged Arc (SAW)	Up to 38.1 (1.5”)	10ºC (50ºF)	AWS F7XX-EXXX-XX
	>38.1 (1.5”) to 63.5 (2.5”)	65ºC (150ºF)
Flux Cored Arc (FCAW)	Up to 38.1 (1.5”)	10ºC (50ºF)	AWS E7XTX-X
	>38.1 (1.5”) to 63.5 (2.5”)	65ºC (150ºF)

Supplementary Requirements

By agreement between the purchaser and plate manufacturer, the following Supplementary Requirements may be

specified on the purchase order:

• S1 (Ultrasonic Examination),

• S2 (Notch Toughness Test at Lower Temperature),

• S3 (Additional Tension Test),

• S4 (Through-Thickness [Z- Direction] Testing),

• S5 (Low Sulfur Steel for Improved Through-Thickness Properties),

• S7 (Low Nitrogen Content for Improved Notch Toughness in Strain-Aged Condition),

• S8 (Strain-Aged Charpy V—Notch Impact Tests),

• S11 (Preproduction Qualification)

• S12 (Notch Toughness Using Drop Weight),

• S13 (Surface Quality) and

• S14 (Thickness Tolerance).