New Steel Triples Hull Collision Performance

By MarEx 2014-08-14 19:28:00

A Mitsui O.S.K. Lines bulk carrier is the first vessel to adopt NSafe-Hull, a highly ductile steel plate for shipbuilding with improved collision safety. NSafe-Hull was developed by Nippon Steel & Sumitomo Metal (NSSMS) and adopted through a collaboration between NSSMS, Imabari Shipbuilding and the National Maritime Research Institute (NMRI).

NSafe-Hull has excellent ductility while maintaining the workability (e.g., machinability and weldability) of conventional steels, which substantially improves ship’s collision safety. NSSMC developed NSafe-Hull by designing its chemical composition and then controlling its microstructure at a crystalline scale.

Because of the superior ductility of the material, the energy absorbed before hull failure in a side-on collision is roughly triple of that for a ship made of conventional steels. Owing to its improved anti-breaking performance in case of collision, it contributes to preventing oil leakage resulting in environmental pollution  and the ingress of water into cargo holds which directly leads to cargo damage and may result even in capsize.

On the ship for Mitsui O.S.K. Lines, approximately 3,000 tons of NSafe-Hull was used for the structural parts where high collision safety performance was required, such as the side plates of cargo holds and fuel tanks. 

NSSMC is planning to conduct more advanced analyses with the support of the “Joint R&D with Industries and Academic Partners” scheme of ClassNK. ClassNK is considering assigning notations to ships with higher safety, such as ships which use NSafe-Hull in order to further improve ship safety.

NSSMC, Imabari Shipbuilding and NMRI will continue contributing to safe, secured and environmentally friendly marine transportation by promoting the adoption of NSafe-Hull for a wide variety of ships.

Outline of the bulk carrier

Deadweight: 206,600 tons
Size: Length overall: 299.94m
Breadth: 50.00m
Depth: 24.70m
Built by Saijo Shipyard of Imabari Shipbuilding
Shipping company: Mitsui O.S.K. Lines
Launched on August 2, 2014
Amount of NSafe-Hull used: Approximately 3,000 tons