S355NL vs S355N Key Differences

S355NL vs S355N: Key Differences

S355N vs S355NL is a critical comparison for selecting structural steel under the EN 10025-3 standard, which specifies normalized or normalized rolled weldable fine grain structural steels. Both S355N S355NL grades offer high strength and fine-grain properties, but they differ significantly in low-temperature toughness, making them suitable for different environments. This article examines the chemical composition, mechanical properties, weldability, and applications to highlight the S355NL vs S355Nlo differences, addressing core keywords s355n vs s355nl, s355n s355nl, and s355nl vs s355nlo. For more details, visit our EN 10025-3 S355NL normalized structural steel plate.

Overview of S355NL and S355N

S355NL (EN 10025-3)

S355NL is a fine-grain structural steel, normalized or normalized rolled, with:

• S: Structural steel.
• 355: Minimum yield strength of 355 MPa (≤16 mm).
• NL: Normalized, with impact toughness tested at -50°C for low-temperature applications.

Its superior toughness suits cold climates like arctic offshore platforms.

S355N (EN 10025-3)

S355N is also a fine-grain structural steel, normalized or normalized rolled, with:

• S: Structural steel.
• 355: Minimum yield strength of 355 MPa (≤16 mm).
• N: Normalized, with impact toughness tested at -20°C.

S355N is designed for moderate-temperature environments, such as general construction in milder climates.

Note: The keyword s355nl vs s355nlo likely refers to a typo or variant of S355NL, as "S355NLo" is not a standard grade. This article assumes it relates to S355NL for comparison purposes.

Chemical Composition Comparison

The S355N vs S355NL chemical compositions are nearly identical, as both are specified under EN 10025-3 with similar alloying for fine-grain properties.

Carbon Equivalent (CEV):

• S355NL: ≤0.43% (≤63 mm).
• S355N: ≤0.43% (≤63 mm).

The S355N S355NL difference is minimal, with S355NL having slightly lower phosphorus (0.025% vs 0.030%) and sulfur (0.015% vs 0.025%), improving toughness and weldability for colder conditions.

Mechanical Properties Comparison

The primary S355NL vs S355Nlo difference lies in low-temperature toughness, with similar strength profiles.

Strength: Both grades share identical yield (355 MPa) and tensile strengths (470-630 MPa) for similar thicknesses, ensuring comparable load-bearing capacity.
Toughness: The key S355N vs S355NL difference is impact toughness. S355NL’s -50°C testing makes it ideal for sub-zero environments, while S355N’s -20°C testing suits milder climates.
Thickness Range: Both support up to 250 mm, with consistent properties across thicknesses.

Welding and Heat Treatment

• S355NL: CEV ≤0.43% ensures excellent weldability with GMAW or SAW (EN 1011-2). Preheating (100-150°C) for >20 mm; PWHT (550-650°C) optional. Consumables: ER70S-6 (GMAW), EM12K flux with EH14 wire (SAW).
• S355N: Identical CEV (≤0.43%) and welding properties, though slightly higher sulfur and phosphorus may require marginally more care during welding.

The S355N S355NL welding difference is negligible, with S355NL’s lower impurities offering a slight edge.

Applications

• S355NL:
  • Offshore platforms in cold marine environments.
  • Wind towers in sub-zero climates.
  • Bridges and cranes in arctic regions.
    Its -50°C toughness ensures reliability in extreme cold. See EN 10025-3 S355NL normalized structural steel plate.
• S355N:
  • Building frameworks in temperate climates.
  • Bridges and machinery in moderate conditions.
  • General structural applications where cold toughness is less critical.

The S355NL vs S355Nlo application difference highlights S355NL’s suitability for colder environments and S355N’s cost-effectiveness for milder ones.

Which is Better: S355NL or S355N?

• Choose S355NLfor:
  • Sub-zero environments (e.g., arctic offshore, northern bridges).
  • Applications requiring guaranteed -50°C toughness.
  • Structures where maximum toughness is critical.
• Choose S355Nfor:
  • Temperate climates where -20°C toughness suffices.
  • Cost-sensitive projects with similar strength needs.
  • General construction with less extreme temperature demands.

The S355N vs S355NL choice depends on temperature requirements and budget. S355NL is better for cold climates; S355N is more economical for milder conditions.

Equivalent Grades

• S355NL: ASTM A633 Grade E, Q345E (China), StE 355 (DIN).
• S355N: ASTM A572 Grade 60, Q345D (China), StE 355 (DIN).

See EN 10025-3 S420NL normalized structural steel plate.

Why Choose Gangsteel?

Gangsteel supplies both grades:

• Inventory: Extensive stock in China.
• Sizes: Thickness 6–250 mm, widths 2000/2500/3000 mm, lengths up to 12,000 mm.
• Delivery: 7-30 days globally.
• Certifications: EN 10204 3.1/3.2, UT testing (EN 10160), ABS/LR/BV/DNV approvals.
• Processing: Cutting, welding, bending.

Contact us for EN 10025-3 S355NL normalized structural steel plate.

FAQ

What is the main difference in S355N vs S355NL?
The primary difference is toughness: S355NL is tested at -50°C (≥27 J), ideal for sub-zero climates like arctic offshore platforms, while S355N is tested at -20°C, suitable for milder conditions like general construction in temperate regions. Both have identical yield (355 MPa) and tensile strengths (470-630 MPa).

How do S355N S355NL toughness properties compare?
S355NL offers superior low-temperature toughness (≥27 J at -50°C) compared to S355N (≥27 J at -20°C). This makes S355NL better for extreme cold, such as northern bridges or wind towers, while S355N suffices for moderate climates.

Which is better for cold climates in S355NL vs S355Nlo?
Assuming "S355Nlo" refers to S355NL, S355NL is better for cold climates due to its -50°C impact toughness, ensuring reliability in arctic or sub-zero environments like offshore platforms, compared to S355N’s -20°C limit.

Are S355N vs S355NL weldable?
Both are highly weldable with CEV ≤0.43%, supporting GMAW/SAW with minimal preheating (100-150°C for >20 mm). S355NL’s lower sulfur (0.015% vs 0.025%) and phosphorus (0.025% vs 0.030%) slightly enhance weld quality, reducing the risk of imperfections.

What are applications of S355N S355NL?
S355NL is used in cold-climate offshore platforms, wind towers, and bridges due to its -50°C toughness. S355N suits temperate building frameworks, bridges, and machinery where -20°C toughness is sufficient, offering cost savings.

Can S355N replace S355NL?
S355N can replace S355NL in temperate climates where temperatures stay above -20°C, as both have similar strength. For sub-zero conditions (e.g., arctic regions), S355NL’s -50°C toughness is essential, making it irreplaceable.

Explore related grades like EN 10025-3 S275N normalized structural steel plate.