Sarens has developed this system on behalf of EEW Special Pipe Constructions GmbH, one of the world's leading experts in the manufacture of monopiles, to facilitate the handling of these pieces at its factory in Rostock (Germany) from its transport combination to its customers' cradles, designed to secure the monopiles to the deck supports of the vessels used during transport at sea.
Sarens’ engineering team had to foresee that this system needed to be compatible with monopiles of different sizes and weights, ranging from 375 to 1900 tons, lengths of between 23 and 85 metres, and diameters of between 8 and 9.75 metres.
To achieve this, their team designed a system with two gantries capable of lifting loads of up to 1,900 tons, with a height of 24 metres and a width of 25 metres, which was placed on two steel tracks for ease of movement. Each one has two 650-ton strandjacks, connected to a spreader bar, so that they can be adapted for use with any diameter of monopile.
In addition, so that the system can be easily adapted to the longitudinal lifting position required for each case, one of the gantries was designed to be able to move by means of SPMT (Self-Propelled Modular Transport), thus ensuring the flexibility of the system to handle the monopiles according to the specific needs that arise.
One of the main requirements faced by the Sarens engineering team in the design of this new device was the need to reduce as much as possible the operational time, in order to reduce the waiting period of the transport vessels at the port before leaving for their final destination. To this end, Sarens designed a system that connects and disconnects the cargo slings in a much shorter time.
Sarens has extensive international experience in the assembly and maintenance of wind farms. It is participating in installations in France such as Fécamp, Saint Nazaire, Provence Grand Large or more recently, in the lifting and transport work for the foundation bases of the new offshore wind farm in Saint Brieuc, off the Brittany coast, where it has been able to transport loads of more than 1,150 tons.
