S355J2H Square Hollow Section Steel Tube
Products Description
S355J2His a hot-finished or cold-formed structural hollow section made from non-alloy and fine-grain steel. It is primarily defined under European standards.
Executed Standards:
EN 10210-1:Hot-finished structural hollow sections (the "H" in the grade often signifies suitability for hot finishing).
EN 10219-1:Cold-formed welded structural hollow sections.
Note for Buyers:While the grade name remains S355J2H, the manufacturing process (Hot-finished vs. Cold-formed) affects the surface finish, dimensional tolerances, and mechanical properties slightly. Always confirm which standard your supplier follows.
Square (SHS):25x25mm up to 400x400mm
Rectangular (RHS):30x20mm up to 500x300mm
Wall Thickness:2.0mm up to 20.0mm
Standard Lengths:6,000 mm, 12,000 mm,or as client request
Surface:Galvanized (hot -dip galvanized); Oil ; Black painting.
We supply high-quality S355J2H steel tubes (Material 1.0576) conforming to EN 10210 and EN 10219. This grade offers a minimum yield strength of 355 MPa and guaranteed impact resistance of 27J at -20°C, making it ideal for load-bearing structures in harsh environments. We can offer both hot-finished and precision cold-formed options with full EN 10204 3.1 certification, suitable for galvanizing
Manufacturing Differences: Hot-Finished vs. Cold-Formed
Feature | Hot-Finished (EN 10210-1) | Cold-Formed (EN 10219-1) |
Process | Formed at high temperature (above recrystallization temp). | Formed at room temperature and high-frequency welded. |
Appearance | Scale present (scaled surface), rounded corners. | Smooth surface, sharper corners. |
Tolerances | Slightly wider tolerances on dimensions. | Tighter dimensional tolerances. |
Stress | Stress-free due to heat treatment. | Residual stresses present but suitable for most structural uses. |
Cost | Generally higher due to energy costs. | More economical for standard sizes. |
Dimensional Tolerances (Key for Trading)
When quoting S355J2H square and rectangular tubes, you must specify tolerances. According to EN 10219 (cold formed), the standard tolerances are:
-Side Length (B /H):
< 100 mm: ±1% (min ±0.5mm)
100-200 mm: ±0.8%
200 mm: ±0.6%
-Wall Thickness (T):
T ≤ 5 mm: ±10%
T > 5 mm: ±0.50mm
- Corner Radius:Approx. 1.6T to 2.4T (for T≤6mm)
-Straightness:Max 0.15% of total length (or 3mm per meter)
Applications & End-Users
S355J2H is a structural grade suitable for heavy-duty and low-temperature environments. Your clients typically use these tubes:
Construction:Bridges, high-rise buildings, cranes, piling, and stadiums.
Mechanical Engineering:Agricultural machinery, truck trailers, and bus frames.
Renewable Energy:Solar trackers and solar parking structures.
Infrastructure:Scaffolding and formwork.
Quality Control
Element | Percentage (%) Max |
Carbon (C) | ≤ 0.22 |
Silicon (Si) | ≤ 0.55 |
Manganese (Mn) | ≤ 1.60 |
Phosphorus (P) | ≤ 0.030 |
Sulfur (S) | ≤ 0.030 |
Carbon Equivalent (CEV) | ≤ 0.45 |
Yield Strength
The yield strength varies depending on the wall thickness (t).
t ≤ 16mm:≥ 355 MPa
16mm < t ≤ 40mm:≥ 345 MPa
40mm < t ≤ 63mm:≥ 335 MPa
63mm < t ≤ 80mm:≥ 325 MPa
80mm < t ≤ 120mm:≥ 315 MPa
Tensile Strength
Property | Value |
Tensile Strength (Rm) | 470 - 630 MPa (for thickness >3mm) / 510 - 680 MPa (for thickness ≤3mm) |
Elongation (A) | Min. 20% (Longitudinal) |
Impact Toughness (Charpy V-notch) | 27 J minimum at -20°C |
