Trelleborg to Carry Out BorWin Gamma Floatover Installation

Trelleborg’s engineered products operation has been awarded a contract by Petrofac for its first floatover installation of an offshore converter platform – BorWin3 (BorWin Gamma) wind farm project.

Image source: Trelleborg

A consortium between Siemens and Petrofac has been contracted by TenneT to design, build and install the 900MW Offshore HVDC converter platform BorWin gamma. The platform will be installed in the German Exclusive Economic Zone in the North Sea, 130 kilometres off the coast at 40 metres water depth.

Siemens will supply the HVDC transmission technology, while its consortium partner, Petrofac, will be responsible for the construction and installation of the platform.

Vincent Tan, Sales and Marketing Manager for Trelleborg’s engineered products operation, said: “BorWin3 is only the third wind farm converter project in the world to utilize floatover technology, so it is a significant project not only for Trelleborg, but the industry too. For the installation of the 18,500 metric tonne topside onto the substructure, we have been contracted to supply six sets of leg mating units and the same amount of deck support units.”

Trelleborg’s leg mating units (LMUs) make a floatover transition possible by damping the forces created as the topside’s load is transferred to the jacket. Consisting of steel structures filled with elastomeric pads, the LMUs are designed to take up the static and dynamic forces of the topside structure, as well as the horizontal forces due to open sea motions during installation. The assembled LMU can be installed either on the topside or substructure.

In addition, deck support units (DSUs) are fixed on the barge that will transport the platform’s topside to its site offshore. These combat the destabilizing effects of adverse weather and sea conditions during transport, Trelleborg explained.

The company said it will begin fabrication of LMUs and DSUs with immediate effect and its solutions are scheduled for delivery in 2018. The entire project is due for completion in 2019.