Balmoral buoyancy mooring development addresses stability, fatigue issues

Offshore staff

ABERDEEN, UK – Balmoral has developed an in-line mooring buoyancy system to secure floating wind turbines and other structures to a seabed anchor while providing uplift to the mooring line.

The system can also serve as a connection point between the bottom and top sections of the line while enabling trajectory and tension to be controlled within the water column.

Traditional mooring systems, the company says, have a pendulum fixture with a tri-plate and buoyancy module secured via a padeye at the base of the steelwork providing an offset center of buoyancy. But this arrangement is at risk of fatigue failure due to the offset loads. To mitigate against this and to change the load transfer characteristics, the company developed its in-line mooring buoy.

A dynamic connection interface allows the different sections of the mooring lines to be tethered both securely and responsively, Balmoral claims, without adversely loading the buoyancy structure.

Central steelwork passing through the dynamic connection, with buoyancy elements mounted either side, leads to the critical interface between components being at the center of the assembly.

Advantages are said to include minimized movement, buoyancy load transfer isolation, reduced fatigue and a more stable outcome for floating wind turbines, FPSOs and other subsea tether connections.

Engineering manager Craig Sharp said the design took into account the combination of material characteristics and associated design controls, derived from detailed analysis, adding that the in-line mooring solutions are designed in accordance with all relevant industry standards.

“As they are provided in modular fashion, our mooring buoyancy systems can be configured to suit specific project uplift requirements,” Sharp said.

08.10.2023