SCHIEDAM, the Netherlands – Shipdock Amsterdam has completed the retrofit of two antiroll tanks onto GulfMark UK’s Highland Defender and Highland Guardian platform supply vessels (PSVs). The work was carried out within one location as a complete turnkey package by two Damen Shipyards subsidiaries.
Niron Staal manufactured the actual antiroll tank and hull sections and Shipdock, part of the Damen Shiprepair & Conversion division, performed the onboard installation. The entire operation required simultaneous action, from the initial steel cutting to the final installation and commissioning, with the two PSVs docked together in Shipdock’s 250-m (820-ft) Panamax drydock. Both Damen companies involved are located within the same shipyard premises in Amsterdam.
The retrofitted antiroll tank units are designed to reduce the roll motion and roll angle during adverse weather conditions. They are placed abeam so that their internal baffles slow the rate of water transfer from the port side to the starboard side. As a large amount of water is restricted on one side of the vessel, this creates an asymmetrical force that opposes the natural but significant rolling motion imparted by a heavy sea swell.
The antiroll sections were installed directly against the aft face of the vessels’ accommodation. Constructed as a complete single section, extending across the entire weather deck from port to starboard side, they extend upward from B deck to the Bridge deck.