Our main products include 1/2inch to 16 inch ERW PIPE/GI PIPE which has been produced according to BS1387/ASTM A53/EN10219/EN10255/EN10217 Standard

Our main products include 1/2inch to 16 inch ERW PIPE/GI PIPE which has been produced according to BS1387/ASTM A53/EN10219/EN10255/EN10217 Standard

Has rich experience in steel pipe processing, can be customized according to customer requirements according to the drawing and sample processing, assist in the development of new products.

Moldova EN 10225 S355G7+N HOLLOW SECTION

EN 10225 S355G7+N STANDARD: EN 10225 GRADE: S355 Series: S355G2+N,S355G3+N,S355G5+M,S355G6+M,S355G7+N,S355G8+N,S355G9+N,S355G10+N.
S420 Series S420G1+QT,S420G3+M. S460 Series S460G1+QT,S460G3+M.

Product Description

What Is EN 10225 S355G7+N 
S355G7+N is a premium high-strength structural steel grade that is specifically designed for the demanding conditions of offshore structures and marine engineering applications. As specified by the European standard EN 10225, S355G7+N offers a unique combination of properties that make it ideal for these environments.

Chemical Composition
Carbon (C): ≤0.14%
Silicon (Si): 0.15-0.55%
Manganese (Mn): 1.00-1.65%
Phosphorus (P): ≤0.020%
Sulfur (S): ≤0.010%
Chromium (Cr): ≤0.25%
Molybdenum (Mo): ≤0.08%
Nickel (Ni): ≤0.50%
Copper (Cu): ≤0.30%
Nitrogen (N): ≤0.010%
Niobium (Nb): ≤0.040%
Titanium (Ti): ≤0.025%
Vanadium (V): ≤0.060%
S355G7+N steel has a controlled chemical composition that contributes to its strength and corrosion resistance. 
Mechanical Properties
Tensile Strength (Rm MPa): 470-630 MPa
Yield Strength (Rp0.2 MPa) varies with thickness:
<16mm: 355 MPa

16-25mm: 355 MPa

25-40mm: 345 MPa

40-63mm: 335 MPa

63-100mm: 325 MPa

Elongation (A%): ≥22%
Impact Energy (Akv J): 50 J at -40°C, demonstrating its low-temperature toughness.
S355G7+N is known for its excellent mechanical properties, which are crucial for withstanding the stresses encountered in offshore applications 

Manufacturing Process
The production of S355G7+N involves a meticulous process that includes steelmaking, casting, rolling, and heat treatment. The steel is typically normalized or normalized rolled (N), which enhances its mechanical properties and ensures consistency across the material.

Heat Treatment
S355G7+N steel is typically supplied in a normalized condition, which is indicated by the "+N" in its grade name. Normalization enhances the material's mechanical properties by refining its grain structure and improving its toughness.
Corrosion Resistance

The low phosphorus and sulfur contents, along with the addition of chromium, provide S355G7+N with good resistance to corrosion, which is essential for marine environments where materials are exposed to saltwater and other corrosive elements.

Weldability

S355G7+N is designed with excellent weldability, a critical factor for steels used in constructing large structures like offshore platforms. Its chemical composition and controlled impurity levels ensure that it can be welded without compromising the integrity of the final structure.

Applications

S355G7+N is used extensively in:

Offshore platforms and marine structures due to its high strength and corrosion resistance.
Heavy engineering and construction where high yield and tensile strengths are required.
It is also utilized in the manufacturing of safety cages, seat frames, and suspension components in the automotive industry, as well as in shipbuilding and the production of wind turbines, pressure vessels, cranes, and drilling rigs.
 

In summary, S355G7+N is a high-strength, corrosion-resistant, and weldable steel grade that is specifically tailored for the challenges of offshore and marine engineering. Its combination of mechanical properties, chemical composition, and heat treatment make it a preferred choice for critical applications in these sectors.