1. The DNV GL grade B steel plate has high strength and can resist the wind impact above the water surface. DNV GL grade B steel plate has good lamellar tearing resistance, which can avoid tearing when receiving external force in thickness direction.
2. DNV GL grade B steel plate has good low temperature impact performance, and some offshore platform steels need to have the performance of service in extremely cold environment.
3. DNV GL grade B steel plate has good welding performance, and the mechanical properties of welded joint are the same or similar to the base metal, which ensures the safety of the whole structure of offshore platform.
4. DNV GL grade B steel plate cleanliness requirements. DNV GL grade B steel plate has a very low content of S, P and other magazine elements, and has high requirements on the morphology, type and distribution of inclusions, so as to avoid fatigue failure of offshore platform under the influence of typhoon and current movement, and ensure the safety of life and property.
5. Requirements for corrosion resistance of DNV GL grade B steel plate. Due to the long-term environment of salt fog, moisture and sea water, marine engineering structural steel plate is subject to severe electrochemical corrosion due to the erosion of sea water and marine organisms. The paint film is prone to severe saponification and aging, resulting in very serious structural corrosion, which not only reduces the mechanical properties of DNV GL grade B steel plate, but also shortens its service life, and is far away from the coast, It can not be repaired and maintained regularly as the ship does. Therefore, the requirements for corrosion resistance of DNV GL grade B steel plate are higher.
