This document specifies qualities for steels for general structural use. This document applies to steel plates rolled on a reversing mill, wide flats, hot-rolled sections and bars, which are used in the as-delivered condition and normally intended for welded or bolted structures.

This document covers 8 steel grades and 4 qualities. Grades S235, S275, S355, and S460 are covered in Annex A. Grades SG205, SG250, SG285 and SG345 are covered in Annex B. Not all grades are available in all qualities, and some qualities have Charpy V‑notch requirements.

The steels specified in this document are applicable to hot-rolled flat products and sections with:

—    thicknesses ≥ 3 mm and ≤ 150 mm for long products of steel grade S460 all qualities;

—    thicknesses ≥ 3 mm and ≤ 250 mm for long products or ≤ 400 mm for flat products of all other grades and qualities;

and no restriction on nominal thickness for grades SG205, SG250, SG285, and SG345 for flat products, sections and long products.

This document does not include the following structural steels, some of which are covered by other International Standards:

—    sheet and strip: refer to ISO TC 17/SC 12 “Continuous mill flat rolled products”;

—    tubular products: refer to ISO TC 5/SC 1 “Steel tubes”.

NOTE 1    Lists of standards covered by ISO/TC 17/SC 12 and ISO/TC 5/SC 1 are available on the ISO website.

NOTE 2    In all parts of ISO 630, the term of "thickness" is considered as "nominal thickness", unless otherwise stated.