The Oceangoing vessels division of Van der Velden Marine Systems has delivered the largest in-house designed BARKE rudders in its history. The two flap-type rudders have been installed onboard the 30,000 m³ trailing suction hopper dredger Congo River. Built for the DEME Group, the trailing suction hopper dredger was launched on 21 January at the IHC Merwede shipyard in Krimpen aan den IJssel (NL).
Designed by the Product Design Department of Van der Velden Barkemeyer GmbH, the two BARKE rudders each have a rudder area of 30 m2 while each flap has an area of 7.5 m2. Each rudder weighs about 75 tons and is designed in such a way that the trailing suction hopper dredger is driven by two propellers with a 5.4 diameter. Both rudders can work at an angle of 45 degrees. The dredger Congo River can reach a speed of 16.6 knots.
The high level of wear and tear, caused by manoeuvring in sandy waters, is a key issue for hopper dredgers. The fully enclosed housing of the original BARKE rudders reduce wear on the linkage components to a minimum while eliminating the risk of sand entry. The high-lift design offers excellent manoeuvring and course keeping performance. Other features are a long lifespan, a reduction of cavitation to an absolute minimum, noise and vibration-free operation, high propulsion efficiency and low fuel consumption.
Congo River will be commissioned in mid-2011 and be named during a formal ceremony in Zeebrugge on 8 July 2011. Due to her wide beam (124.5 ft) and short length (551 ft), this versatile vessel has excellent manoeuvrability and can be used for many purposes. When fully loaded, Congo River has a low draught (39 ft), enhancing her working efficiently in harbours and fairways, on beach suppletion and land reclamation projects, and with long-distance transportation. Fitted with a deep suction dredging installation, the vessel has a maximum dredging depth of over 100 metres.