February 23, 2016
In FIMECC BSA program steel and shipbuilding experts joined their forces to develop novel lightweight marine structures. The utilisation of high-strength steels combined with advanced production technologies results in the weight reduction up to 20 percent bringing numerous advantages and rising competitiveness of Finnish shipbuilding industry.
The new lightweight solution based on high-strength steels enables energy-efficient and eco-friendly large marine structures, such as passenger ships, maintaining and raising the competitive edge of Finnish shipbuilding. “The greatest benefit is that by utilising high-strength steels were are able to build significantly lighter ships. Moreover, high-strength steels enable more efficient production. With high-strength steels less material, energy and welding is needed during the production”, Ari Niemelä, Head of Hull Classification Meyer Turku Oy, describes the benefits of the result.
In addition to energy-efficiency and increased productivity, the developed lightweight structures open new opportunities to design. In innovative passenger ship concepts customer experience and so called “wow-effects” are key design drivers. At the moment the weight of steel is limiting the design of concepts. “The weight reduction can be utilised, for example, by building additional cabin deck”, Niemelä envisions the future.
The trend in shipbuilding industry is towards efficient large marine structures. In order to build energy-efficient and eco-friendly large ships, while maintaining their safe load-carrying capacity, new lightweight solutions are needed. In a case of passenger ships, for example, lighter structure would increase the energy-efficiency and could be utilized to add payload, i.e. one more cabin deck. Advanced solutions give competitive edge to Finnish shipbuilding industry.
To utilize high-strength steel in marine applications means going beyond present rules of ship regulation. To go beyond present rule a holistic approach requiring a hard and systematic work as well as good co-operation between different experts from industry and academy is needed. “FIMECC BSA program with cross disciplinary approach offered fruitful platform for the research and development”, Ari Niemelä describes the importance of the development ecosystem.
Laboratory tests are showing positive performance and application possibilities of high strength steel in large marine structures. Lightweight structures enables the development of energy-efficient and eco-friendly large ships, and new design opportunities. Moreover, lightweight structures improve production efficiency by decreasing the amount of material, energy and welding needed during the shipbuilding. This results in cost savings for both shipbuilder and operator increasing the competitive advantage of Finnish shipbuilding industry.
The lightweight marine structures also open totally new and big customer segment for Finnish steel industry. “Finnish shipbuilding industry is a very potential customer segment of us”, tells Jukka Kömi, Head of Product Development Special Steels, SSAB Europe Oy.
The promising results obtained in laboratory conditions have to be confirmed in shipyard production environment. Due to lack of knowledge about the fatigue resistance of high-strength steel in marine structures, the utilization of high strength steels in marine structures is currently limited. The results of the first tests received a positive response from the classification society. The work aiming to close the gap between laboratory test and actual application continues in FIMECC BSA program.