The ship classification society Germanischer Lloyd (GL) said Wednesday it has developed new route-specific stowage guidelines for container vessels.
The guidelines, available to all GL-classed boxships, is meant to offer container lines additional flexibility to load more containers on deck, while maintaining required safety levels.
“With new route specific loading calculations, GL can assist container lines to accelerate cargo operations in ports and maintain a higher degree of loading flexibility,” the German company said. “Based on long-term statistical data on wave conditions, GL has developed a new class notation for route-dependent container stowage, which reflects realistic routes for the determination of loads on the deck containers and their lashing systems. A route dependent container stowage scheme takes into account that sea conditions vary depending on the chosen sea lanes.”
GL said currently the international standard is to design a vessel for 20 years of operation in the North Atlantic and the same assumptions are applied for the design of lashing systems as well.
“The new GL class notation takes into account that in reality a vessel will not operate exclusively in the North Atlantic, but will also sail in relatively calm regions for a considerable amount of its operational lifetime,” GL said. “Applying long-term statistics, it is possible to derive equivalent safety margins for the determination of loads on the deck containers and their lashing systems for specific routes.”
On routes in calmer waters, the new cargo arrangement plans will enable heavier boxes to be loaded on the upper tiers of deck stacks, more units loaded on the outer stacks, and potentially an additional tier of empty containers where line of sight is not affected.
“GL's analysis of the wave loads on a typical Asia-to-Europe route for a mega-boxer vessel has revealed the potential of departing from the traditional load rules for unrestricted service,” GL said. “This flexibility gives operators the potential to increase the number of loadable containers they are able to carry and reduce the number of empty containers transported as well as more flexible cargo planning and therefore faster stowage.”
The new scheme requires lashing software which will assist the cargo planer, as well as the crew, in providing safe stowage and lashing, while giving greater flexibility to take advantage of opportunities whenever they might occur.
GL said it is currently in discussions with all relevant stakeholders and will have route-specific loading in place by the second quarter of 2013. - Eric Johnson