Standard NBN EN 10225-4:2019
Weldable structural steels for fixed offshore structures - Technical delivery conditions - Part 4: Cold formed welded hollow sections
77.140.10 Heat-treatable steels 77.140.75 Steel pipes and tubes for specific use
This document specifies requirements for submerged arc welded (SAW) and high frequency welded (HFW) cold formed hollow sections to be used in the fabrication of fixed offshore structures. The thickness limit for SAWL circular hollow sections is up to and including 50,8 mm, for HFW circular hollow sections up to and including 25,4 mm and for HFW square and rectangular hollow sections up to and including 12,5 mm. Greater thicknesses for SAWL hollow sections can be agreed provided the technical requirements of this European Standard are maintained. NOTE 1 This document has an Annex E for SAWH round hollow sections with a thickness limit of 30,0 mm, and an Annex F for high strength square and rectangular HFW hollow sections made of steel grades S500 to S700. This European 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. design temperature. NOTE 2 This document has an informative Annex G on the prequalification of steels for fixed offshore structures in arctic areas. Minimum yield strengths up to 700 MPa are specified together with impact properties at temperatures down to -40 °C. NOTE 3 A range of material grades is specified in this standard and the user can select the grade most appropriate to the intended use and its service condition.