SubseaDesign’s wind tower connector: prototype success & path to qualification

The offshore wind industry continues to evolve , despite challenging market conditions. The long-term outlook is driven by the need for larger turbines, cost-efficient installation methods, standardized solutions, and technologies that reduce risk throughout the asset lifecycle. Innovation remains essential to making offshore wind more competitive and scalable. At SubseaDesign, we would like to share the latest developments and the way forward for our Wind Tower Connector.

In 2025, we successfully designed, manufactured, and tested the first prototype at our facilities. The prototype represented a 5° full-scale tower sector, including full-size segments and the hub profiles, connected with M72 bolt. The structural loading was applied using two 250-ton hydraulic jacks, corresponding to approximately 700 MNm bending moment. The testing programme was designed to:
-Simulate the complete make-up sequence, including land-out, torqueing and tensioning.
-Verify structural behaviour under representative tower loading.
-Correlate measured stresses with FEA predictions.
-Evaluate sensitivity to bolt preload.
-Investigate the influence of manufacturing and assembly tolerances on connector performance.

The successful test campaign confirmed the technical feasibility of the concept and provided valuable validation data for the next stage of development.
Today, the project continues with technical assessments and technology qualification. Together with DNV, we are now progressing through the qualification process towards Technology Qualification Level D—an important milestone in documenting the technology’s maturity and reducing technical risk before the next phase. It promises to be an exciting autumn as we continue this journey, and we look forward to sharing more milestones along the way.

visit wind tower connector page