Damen Marine Components (DMC) will supply FLEX tunnels, propeller nozzles, manoeuvring systems and rudders to Rensen-Driessen Shipbuilding (RDS), Zwijndrecht, the Netherlands, for two newbuild inland tanker vessels
The newly developed tanker designs are based on a series of four large ‘XXL tankers’ that were built at the RDS shipyard between 2017 and 2020, and each of the new tankers will be equipped with two FLEX tunnels, two propeller nozzles and two manoeuvring systems with four rudders. The Van der Velden FLEX tunnel products optimise water flow to the large two-metre propellers in the propulsion array.
The retractable-winged ’tunnels’ run from the duct under the hull in front of the propellers. When the tanker navigates in deep water with a full load, the wings can be retracted into the hull while the propellers are fully submerged to generate thrust. When operating in shallow water with limited draft, the wings are deployed, allowing water to flow under the hull towards the propellers. The design enables the tanker to operate more efficiently in shallow water, according to Van der Velden.
Like the earlier XXL tankers, the new vessel design was jointly developed by RDS and Rommert Ship Design and completed for improved hydrodynamics by DMC. The new design incorporates lessons learned from previous projects, the participants said.
“Working with these suppliers has enabled us to optimally develop new ships,” said Mr Driessen. Completion of the vessels is expected by the end of 2023.
Behind the two nozzled propellers on the new XXL tankers, two independently operated Van der Velden HD 240 two-rudder systems are installed. Each set of connected rudders has an asymmetrical 60-80 degree rudder angle, which, according to the manufacturer, provides excellent manoeuvrability even at very low speed.
To be able to transport as much liquid cargo as possible in the Amsterdam-Rotterdam-Antwerp sailing area, the XXL inland tankers have an overall length of 135 m and beam of 22 m. with a deadweight of 13,000 tonnes.
RDS director Wim Driessen and DMC area sales manager Leo van Zon signed the contract for the supply of the propulsion systems. To date, 13 vessels with FLEX tunnels are operational, with seven more under construction.
