Ship builders and vessel-owners have a common interest in protecting marine vessels against corrosion and biofouling. For ship builders, protection involves the application of a paint system incorporating a primer, a binder and a final coat of either (a) antifouling paint -which poisons already attached marine life- or (b) a fouling–release coating which deters things from attaching themselves in the first place. Against corrosion, ship owners are “ looking for products that will protect their assets over the long term without the need for extended maintenance” whilst for fouling control coatings, owners are “ looking for consistent fouling control protection across a full dry dock cycle with minimum drop in vessel performance” states Mirjam Veenhof, spokesperson, AkzoNobel Global Communications.
The vast majority of coatings are applied when the ship is under construction or during routine dry dockings. Specialised heavy duty marine coatings are produced by many companies including, Ecospeed, Hydrex, VapCor Marine Coat SeaGuard. Heavy duty coatings are applied to areas of extensive wear and tear such as near rudders, where surfaces need protection against the cavitation damage caused by the propellers as they churn the water, or, complex structures that are costly and difficult to repair, such as water ballast tanks. For the general parts of the ship, paint manufacturers such as Akzonoble, BASF and Hempel provide a range of general-purpose paint protection systems. Products from different manufacturers may employ similar technologies but each develops its portfolio of corrosion and biofouling control products to work together. In either product segment, there is a balance to be found between the cost and the performance and maintenance requirements. For example, according to Maersk Line, on-board maintenance paint needs to be first and foremost technically ” surface tolerant with a good film build” and secondarily, able to satisfy issues such as port availability, delivery time and price, which are important factors in the purchase decision. For dry-docking paints and predominantly antifouling paints, Maersk is looking for performance “both antifouling and speed performance” whilst “price is also a factor”. The global anti-fouling paint market is expected to reach U.S. $9.22 billion by 2021
This feature takes a look at some of the issues involved in tackling biofouling and corrosion. Read more coatings_newman