Offshore energy chain for strong cable guidance on a wind farm drilling rig

The Herrenknecht Offshore Foundation Drilling is currently the largest offshore drilling rig and is being used by DEME, a global leader in dredging and land reclamation, solutions for the offshore energy market, environmental and infrastructure works, to install monopile foundations in Saint Nazaire. The first offshore wind farm in France is being built here. A total of 73 monopiles with a diameter of 7,700 mm have to be drilled at depths of between 6 and 24 metres. It is also the first offshore wind farm in the world where rock drilling for XL monopiles is one of the main installation techniques. The new offshore foundation drilling machine used for this purpose offers considerable ecological and economic advantages over conventional methods. At the same time, however, it poses a major challenge, as the huge machinery must be safely supplied with power from the ship. It was not only the corrosive environment that posed a problem for the safe cable routing. The long travel distances of the drill working deep in the rock also demanded a robust and reliable solution.

In order to ensure a high level of planning reliability during the drilling work for the monopile foundations, DEME now relies on our offshore energy chain OSC. The cable routing, which is also used for supplying shore power to ships in harbours, can also be used in particularly harsh conditions thanks to a high-strength integrated tension cable in its two chain links. The plastic-energy chain is not only suitable for corrosive environments, but also for high levels of dirt, strong vibrations and impacts. The modular design of the energy chain ensures a flexible layout of the internal cable and hose. Overall, the system guarantees long-term protection of the cable and hose as well as user-friendly handling for fast project planning and commissioning. And so that the long offshore cable can be compactly accommodated and safely unwound as the drill is lowered, it was wound onto a huge cable drum that was installed on a ship.