HST Hull Cleaning assists ships to travel faster through the water, consume less fuel and emit lower green-house gases thus ensuring that their hulls are clean and smooth – free from fouling organisms such as slime, algae, weed and/or molluscs. An effective anti-fouling technology, HST also ensures that hull fouling on commercial and military shipping is reduced/eliminated as a vector for the introduction of imported marine pests.
The ship had been in water for 21 months with weed growth accumulating over that time to between 10mm and 20mm on the vertical sides. HST hull cleaning was applied to both sides of the ship over two consecutive days. There were no interruptions to the ships operation. Hull Surface Treatment requires no services from the ship and is fully self sufficient. The photos show the side of the ship before application and the results six months after the application when the ship was dry docked.
The MV TORRENS was treated with HST 4.5 months prior to dry-docking. Before the treatment the hull had 100% coverage of 30mm weed and algae on the lateral areas thinning to 10mm at the bilge keel. The photos show a comparison of the hull before HST and then after when the ship was dry-docked in Singapore. Between the treatment and dry docking new re-growth can be seen starting along the top section near the water line. HST is designed to keep the hull as close as possible to dry docking condition without the aggressive action of scrubbing or water blasting and the associated damage to the anti fouling paint plus environment. Treatment and re-growth frequency varies depending on the ships underwater coating condition, its operations and geographical areas of operation.
HST was applied to the five ships – KOKOPO CHIEF, CORAL CHIEF, HIGHLAND CHIEF, PAPUAN CHIEF and ISLAND CHIEF. All the vessels were heavily fouled and the anti fouling paint on each was in very poor condition. This was due to the scrubbing action of brush carts used previously to clean the hulls of growth. The unfortunate result of this is the removal in large quantities of the expensive anti fouling paint along with increased growth. Each time a vessel is scrubbed using the old abrasive methods the paint becomes less and less effective in expediting the re-fouling of the hulls. The photos show a typical section of the hulls taken after a period of around 3 months since the HST application.
Rhapsody Of The Seas
HST treatment applied to both sides of the hull after the ship had been in water for 48 months after last being scrubbed. Weed growth had accumulated in that time to between 10mm and 20mm on the vertical sides. HST was applied to the Port side of the ship first and then the Starboard side 1 month later. The photos are of the port side and taken 21 days after the application to the port side.