C1 Connections and Heerema Marine Contractors successfully test the C1 Wedge Connection offshore

The Hague (NL), November 7th, 2022

C1 Connections BV and Heerema Marine Contractors have successfully tested the C1 Wedge Connection™ offshore. The C1 Wedge Connection™, developed by C1 Connections BV is a high-capacity connection that can be installed faster and safer than conventional bolted flange connections. It can be used in off- and onshore wind turbines, both in turbine towers and foundations. The installation of the tower on board the Heavy Lift Vessel (HLV) Thialf was performed as part of the preparations for the Arcadis Ost project, for which Heerema will install 27 wind turbines for the Belgian developer Parkwind.

The C1 Wedge Connection™ can deliver the high capacity that is needed for the next generation wind turbines, which continue to grow in size and are installed on sites in increasingly harsh environmental conditions, or on floating platforms. The C1 Wedge Connection™ will improve the LCOE by reducing CAPEX and OPEX while allowing safer installation.

Conventional bolted L-flange connections are reaching their capacity limits and are complex to design, install and maintain. This is where the C1 Wedge Connection™ will make a significant difference. During the offshore test, C1 Connections and Heerema Marine Contractors have demonstrated that the C1 Wedge Connection ™ enables a safe disconnection of the tower from a grillage on a barge. The alignment and quick connection of the tower was successfully performed without any personnel below the suspended load. The C1 Wedge Connection ™ features pre-installed fasteners, and only light-weight tools are needed to finalize the connection.

The development of the C1 Wedge Connection™ started in early 2017 in close collaboration with Delft University of Technology (TU Delft). From the offset, this technology has received support from the Dutch Government Agency RVO, with several industry partners having contributed to its further optimization.

“Prior research and testing have demonstrated that the C1 Wedge Connection™ delivers a very high fatigue and ultimate capacity. The collaboration with Heerema has allowed us to demonstrate offshore that we can make installation much safer and faster, which are key benefits the entire industry can benefit from.”.


About C1 Connections B.V.

C1 Connections BV is a Dutch privately-owned company dedicated to developing and commercially exploiting the C1 Wedge Connection™. C1 Connections BV strives to deploy the C1 Wedge Connection™ as the future standard for highly loaded connections in off- and onshore wind projects.


For more information on the C1 Wedge Connection™, please contact:

Jasper Winkes

+31 6 27367351



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