Super silent double wall tunnels produced for Berg Propulsion

26 February 2013

Design

The Berg Silent tunnel is a full length double wall tunnel with a resiliently mounted inner tunnel. The vibration isolation system will prevent any vibrations created by the thruster propeller to reach the hull structure of the vessel. This tunnel system for thruster noise elimination is tailor-made to fit each and every type of vessels from offshore vessels to cruise liners.

Production

Damen Marine Components has been involved from the start of the project, making it possible to give input during engineering phase. The double wall tunnels are produced as two regular bowthruster tunnels which are shifted inside each other and kept in place with resilient mounts/ vibration dampers. At the thruster mounting side the flexibility and water tightness between the two tunnels is realised with a double rubber flange.

Outside diameter 3,300 mm
Length 4,000 mm
Weight 28,000 kg

End use

The destination of the double wall tunnels is an offshore wind power jack-up vessel. The end user has chosen this design to reduce the sound level above the double wall bowthruster and equip the space with crew cabins.