Bulk carriers are commercial vessels carrying a range of cargoes, such as edible stuff, coal, metal ores, and cement in their cargo holds. These vessels can be divided into various classes based on their size and trading routes they can operate in. They can range from very large ore carriers (> 300,000 DWT) to small coastal trading vessels (< 5,000 DWT).
The key considerations for bulker operators include maintaining vessel speed and meeting schedules which can allow them to have maximum trading route flexibility. Minimised fuel consumption for long term charters and reduced off-hire maintenance times are also of high importance. Because bulk cargo can take a long time to discharge, bulkers often spend more time in port than other ships. These static periods coupled with the low speed of bulkers presents a big challenge for hull coatings. Another consideration is the environmental impact of hull coatings.
Bulk carriers generally trade globally in very high fouling challenge regions with heavy loads. Furthermore, they normally have frequent stops due to the loading and discharging of cargoes. The longer time required for discharging cargo which is due to health and safety considerations as well as logistics, means increased frequency of static periods which presents significant challenges to underwater hull coatings, to maintain hull efficiency during vessel operations.
Results, Return on Investment and Future Plans
Over 300 successful applications of Intersleek have been completed on bulk carriers.
Intersleek 1100SR has demonstrated excellent slime release properties after long static periods. This allows customers to access foul release technology with reduced hull maintenance compared with other antifouling offerings. Thus, it gives a financial and environmental benefit to customers.
The picture below shows the hull performance of Intersleek 1100SR after a 45-day static period in the high fouling challenge of Indonesia on a bulker named Wooyang Banders (DWT 73,700). This vessel was coated with Intersleek 1100SR in November 2013. From the pictures, negligible level of slime can be observed after the long static period during April – May 2017.