Marine Coatings: Beyond Paint

Published Apr 23, 2012 1:44 PM by The Maritime Executive

By Art Garcia

Early in March marine coating manufacturer Hempel completed painting the hull of a 40-year-old container vessel, a hull refurbishment project that will pay for itself in about six months. The shipowner will gain “some phenomenal” fuelsavings with the smoother, slicker vessel bottom slicing through the water at a faster speed and slower rate of fuel consumption.

“The savings offset the cost of the coating, a product that’s very expensive in comparison with old anti-fouling paints. The payback on these newer products is very rapid,” said Mike Pevey, North American Marine Manager for Hempel USA in the Danish company’s Houston office. “We see 10 percent or more in fuel savings by putting these products on the hull and absolutely an increase in speed.”

Measurable Savings, Prompt Payback
Depending on the size of the hull, the cost of Hempel’s new environmentally friendly fouling-release coating can be up to four times more expensive than a conventional anti-fouling paint project. But not only is the return on investment higher, with new technology the savings can now be measured.

“Perhaps the most important issue in marine coatings is being able to measure the effect of anti-fouling on the performance of the hull and, therefore, on the fuel performance and energy efficiency of the vessel,” said Geir Axel Oftedahl, Business Development Director for Hull Performance Solutions at Jotun, headquartered outside Oslo, Norway. Basically, anti-fouling paint is applied on a vessel to prevent the accumulation of barnacles, mollusks, seaweed, slime and other drags on a ship’s movement. It’s always been difficult to determine exactly the effects of different coatings on a vessel’s energy efficiency.

“We are now putting a lot of effort into making it possible to measure with a high degree of accuracy and reliability the effectof a particular coating on the fuel consumption of a particular vessel,” said Oftedahl. “From our perspective, the challenge is that most marine executives are not aware of the tremendous impact the hull coating has on the performance of a vessel.” Having an accurate measurement of that impact has historically been extremely difficult because there are so many factors that affect a ship’s performance, including wind, waves, load, trim, bunker quality and potential deterioration in engine performance.

“There’s always room for improvement, of course, but we’re at the stage right now that we’re comfortable in offering a guarantee based on what we’re measuring,” Oftedahl explained. “An increasing number of customers are willing to sign a contract based on that measurement technology. It really comes back to if you cannot measure the return on your investment, you cannot invest. Our customers now are able to measure the return on their investment and, as a consequence, are able to begin investing both time and effort to better understanding hull coatings.”

Jotun has fine-tuned its measuring method to the point that it can now offer customers an iron-clad guarantee. “That really changes the landscape because it means that, instead of making bold claims, we’re now able to go to customers and tell them they can measure the impact of our products,” Oftedahl said. “We guarantee that over a three-year, five-year or seven-and-a-half year period, whichever is relevant to the customer, our product’s performance is going to be within a pre-defined range.” The guarantee time spans are based on the docking intervals for vessels, up to seven-and-a-half years for container ships.

Selling Performance, Not Paint
Selecting the best antifouling technologies available from Jotun can easily save in the range of seven to 14 percent in bunker costs, Oftedahl stated. Jotun’s top-of-the-line product is SeaQuantum X200. The new product is delivered as part of an end-to-end hull performance solution that includes not only a cash-back, high performancebguarantee but a method for measuring the impact of antifouling on vessel efficiency “every second of every day over the full lifetime of the solution."

Under the guarantee, Jotun will pay back part of the paint cost if the promised level of performance isn’t delivered, typically in the range of 50 to 60 percent. “In short, our customers are moving from buying paint to buying performance,” said Oftedahl. “If they get the performance they have been promised, they pay the full price. If not, they get a substantial refund.”

Do refunds occur very often? “Luckily, not yet,” he said. “We launched this high-performance concept early last year. It will take five years before we can truly know the answer to that question. Of course, we’re very confident that will not happen. Otherwise, we wouldn’t be able to offer such guarantees.”

Three Main Concerns
Raouf Kattan, Chairman of the IMO Advisory Council for NACE (National Association of Coatings Engineers) and Managing Director of coatings consultancy Safinah Ltd., believes there are three “hot topics” that relate to coatings facing shipowners today. First is the cost of fuel, which typically runs close to 60 percent of total operating costs and drives maintenance of underwater hulls to minimize vessel resistance and reduce fuel consumption. Second is greenhouse gas emissions, which reinforce the need for underwater hull maintenance as well as propulsion system maintenance and consideration of alternative fuels. Third is selection and installation of ballast water treatment systems. “The issue with ballast water treatment systems is most of them – in fact, all of them – in one way or another alter the chemistry in the ballast tank,” Kattan explained. “What is not known is how big a risk this poses to ballast tank coatings. We know there’s a risk. What we don’t know is which systems pose what risk to which type of coating and the magnitude of the risk, which can range from a small problem to a catastrophic problem.”

From the shipyard’s viewpoint, newbuilds come with a 12-month guarantee, so the yard wants to ensure the product achieves that goal. “A builder’s primary concern is how that paint system may affect its productivity and output,” he commented. “So if the paint is more complicated to apply, takes longer to apply or is made up of a scheme with many coats, then a shipyard is going to assess the proposed scheme and its impact on output and costs.”

Shipyards have invested heavily in improving steel and outfitting work while investment in coating productivity has lagged, so much so that in many yards the coating process is, as Kattan put it, “the bottleneck of their output.” Given the current state of the industry, “Anything that can improve the yard’s productivity is a must-have. The paint companies are aware of this and are always searching for technologies that can assist the yards in meeting their goals.”

Likewise, shipowners are increasingly aware of the pressure to control operating costs in the face of depressingly low freight rates. This, together with increased classification society focus on corrosion in ballast and crude oil tanks, means owners want to be sure the coatings meet their lifecycle needs that often extend well beyond the 12-month warranty period offered by the shipyard.

Managing Risk
Owners are presented with an array of promises about fuel savings. They also face options on a multitude of systems for ballast water treatment systems. The risks of poor decision-making, in terms of coating selection, are increasing. Attitudes towards coating selection and understanding the risks associated with coating performance are increasingly at the forefront of owners’ concerns. To minimize the risks, Kattan suggests they consider:

Improved vessel design to minimize corrosion risk and improve hull performance.
Paying more attention to contractual terms and moving to performance-based specifications.
Ensuring correct product selection against the specifications based on where, when and how the work is done.
Weighing carefully the process of application and its likely impact on performance.
Ensuring proper management systems are in place to maximize benefits from the coating throughout its life.
Ensuring the coating meets its operational performance requirements in service.

In short, treat the coating system as you would any other engineering system on board the vessel, advised Kattan. “By doing that,” he said, “the risk of poor coating performance will be minimized.” - MarEx