This European Standard specifies requirements for weldable structural steels to be used in the fabrication of fixed offshore structures in the form of plates up to and including 150 mm thick. It also specifies sections up to 63 mm thick except for sections delivered in the as-rolled condition which are permitted up to 25 mm thick only. Seamless hollow sections up to and including 40 mm thick and high frequency electric resistance welded hollow sections up to and including 20 mm thick are specified. Greater thicknesses for sections and hollow sections may be agreed, provided the technical requirements of this European Standard are maintained.
For plates the thickness limitations are:
S355G2+N, S355G5+M, - up to and including 20 mm
S355G3+N, S355G6+M - up to and including 40 mm
S355G7+N, S355G8+N, S355G9+N, S355G10+N - up to and including 150 mm
S355G7+M, S355G8+M, S355G9+M, S355G10+M - up to and including 100 mm
S420G1+Q, S420G1+M, S420G2+Q, S420G2+M - up to and including 100 mm
S460G1+Q, S460G1+M, S460G2+Q, S460G2+M - up to and including 100 mm
The standard is applicable to steels for offshore structures, designed to operate in the offshore sector but not to steels supplied for the fabrication of subsea pipelines, risers, process equipment, process piping, and other utilities. It is primarily applicable to the North Sea Sector, but may also be applicable in other areas provided that due consideration is given to local conditions e.g. temperature.
In the case of hollow sections formed from plate with the seam fusion welded, this European standard covers only the requirements of the plate material.
Minimum yield strengths up to 460 MPa are specified together with low temperature impact properties at temperatures down to -40 °C.
This European standard applies to material supplied ex-mill or from merchant's stock.