S355 / 1.0570 structural steel

What S355 / 1.0570 is

S355 is weldable structural steel in the 355 MPa strength class. W.Nr. 1.0570 belongs to the older designation S355J2G3 – St52-3 in the DIN era. Today the certificate typically states S355J2 (1.0577), unless the drawing specifies a different suffix. J2 means impact toughness at −20 °C. It is welded. It is not hardened. If an older drawing states 1.0570 or S355J2G3, we supply the current EN grade and state it on the certificate.

Typical applications

Welded structures, plate and bar where 355 MPa is what the calculation requires. Plate is the volume. Round and flat bar when the part is machined from bar. Tube in S355J2H when it is a structural hollow section.

• Welded structures in plate and bar
• Plate – the volume in S355
• Round and flat bar for parts machined from bar
• S355J2H when it is a structural hollow section

Delivery condition and dimensions

The typical condition is +AR or +N. We source S355 from European partners as plate, flat bar and round bar, cut to your dimensions and ship the certificate with it. From a single cut piece to larger batches – no minimum charge, so you do not have to buy a full commercial length to get what you need. State thickness or cross-section, format or length, quantity and which suffix the certificate should carry. Stock status is confirmed on enquiry.

Machining and welding

S355 is welded. It is not hardened – if the part has to be hardened, it is a quenched and tempered steel, not S355. We cut plate to drawing; round and flat bar we cut to length when the part is machined from bar. The carbon ceiling to EN 10025-2 rises with thickness, and the product analysis can sit slightly above the cast analysis.

Certificates and documentation

S355 can be supplied with a material certificate to EN 10204, depending on the producer, the dimension and the specified requirements for the delivery. On a welded structure, the certificate has to show the analysis, the strength class and – where the standard requires it – the impact toughness. EN 10204 3.1 can be supplied on a wide range of our materials, and 3.2 is ordered when the project requires a third party. If the drawing designation is S355J2G3 or 1.0570, the current EN grade is stated on the certificate.

Designations

S355 is the strength class; the suffix states the impact toughness class. 1.0570 is the W.Nr. of the older designation S355J2G3, called St52-3 in DIN. The current grade to EN 10025-2 is S355J2 / 1.0577.

• S355 / 1.0570 – older designation S355J2G3, DIN St52-3
• S355J2 / 1.0577 – current grade to EN 10025-2, impact toughness at −20 °C
• S355J2H / 1.0576 – structural hollow sections

Limits and alternatives

S355J2 when −20 °C has to be documented. S355NL for lower temperatures. S690QL when weight has to come down and the welding procedure can follow. Switch to a quenched and tempered steel if the part has to be hardened – S355 is not a shaft steel.