API 2H Gr50

API 2H Grade50 Offshore Steel Plate

Nearest Equivalent Grade : EN10225 S355G7+N, S355G7+M, S355G8+N,S355G8+M, BS7191:1989  355EN, 355EMZ

Characteristic :

API 2H Grade50 is an Intermediate-Strength, Heat Treated (Normalized) Carbon-Manganese Structural Steel Plate for

welded construction of offshore structures/offshore platforms.

API 2H Grade 50 has a minimum yield strength of 50ksi (345MPa) and a minimum transverse

Charphy V-notch impact toughness of 30 ft-lbf (41J) at -40degree C .

This grade steel plate can be multi-certified to ASTM A633 Grade C, ABS DH36/EH36, ASTM A537 Class 1 and

MIL-S-22698 REv C in thickness to 50.8mm (2inches).

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

the American Bureau of Shipbuilding (ABS).

Application :

API 2H Grade50 is intended primarily for use in critical areas or sections of offshore structure projects that must exhibit

good impact toughness and resistance

to plastic fatigue loading and lamellar tearing. 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 2H Grade50  is also used as a piling material for

bridge construction due to its fracture, vibration and torque resistance.

API 2H Grade 50 is therefore not only in effective material for floating and rigid offshore platform construction, it also has other uses as

a high yield and highly specified structural grade material.

Key Features:

•       Structural offshore grade for critical applications

•       High yield with excellent fracture and impact resistance

• Resistance to lamellar tearing
• Though classed as a marine grade, can be used in a variety of applications due to stringent spec

Chemical Composition (wt%, max.unless indicated)

Mechanical Properties

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

Thickness, t mm (in.)	0.2% YS ksi (MPa), min.	UTS ksi (MPa)	Elongation in 50mm(2”), min.%	Elongation in 200mm (8”) , min. %
t ≤ 63.5 (2.50)	50 (345)	70 to 90 (483-620)	21	16
t > 63.5(2.50)	47 (324)	70 to 90 (483-620)	21	16

Charpy V-notch Impact Testing

Charpy V-notch Impact Testing is performed using transverse specimens in accordance with ASTM A370.

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 (wt %, max. unless indicated)

	C	Mn	P	S	Si	Al	Cb	Ti1	N2	V2	CEV t ≤ 2”	CEV t > 2”
Heat	0.18	1.15-1.60	0.030	0.010	0.05-0.40	0.02-0.06	0.01-0.04	0.020	0.012		0.43	0.45
Product	0.22			0.015	0.05-0.45

1. Minimum value, if any, shall be as agreed upon and stated on the order.
2. Shall not be intentionally added.

Heat-Treated (Normalized) Structural Steel

Carbon Equivalent : CEV = C + Mn/6 + (Cr+Mo+V)/5+(Ni+Cu)/15

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 2H 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)
	>63.5( 2.5”)	110ºC (225ºF)
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)
	>63.5( 2.5”)	110ºC (225ºF)
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)
	>63.5( 2.5”)	110ºC (225ºF)
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)
	>63.5( 2.5”)	110ºC (225ºF)

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 (Individual Plate Testing),

• 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-Hardened Condition),

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

• S12 (Notch Toughness Using Drop Weight),

• S13 (Surface Quality) and

• S14 (Thickness Tolerance)