Successful First Offshore Installation Slip Joint Connection
The turbine was installed on a monopile foundation using the slip joint, an alternative connection between the turbine and the foundation based on friction, where the weight ensures a firm and stable connection. It works like two paper cups upside down stacked on top of each other and installation is performed by simply sliding the tower of the monopile. The installation process is simplified as there is no need for grout or bolts. As a result the installation time is shortened and a reduction in material, equipment and personnel is achieved.
The monopile, manufactured by Sif, was already installed back in May this year. The turbine was transported and installed by Heerema’s DCV Aegir. The vessel picked up the turbine from Sif Rotterdam in one lift. The Aegir installed the turbine as a floating vessel and kept in position by Dynamic Positioning (DP). The installation time only took one hour. It is the first time the slip joint is used for an offshore wind turbine. During a year the turbine will be tested and the collected data will be processed and used for validating lab tests by both TU Delft and TNO. The SJOR project is part of the GROW program. This project is executed with subsidy of the Topsector Energie from the Ministry of Economic Affairs and Climate.