DeepOcean is completing its decommissioning and towing operation of the FPSO Gryphon Alpha in the North Seain a campaign commissioned by TotalEnergies. This intervention marks a precedent in the industry by being executed entirely without divers, using tools designed and developed by the company itself.
Diverless disconnection and safe remote operations
The intervention included the cleaning of collectors and underwater pipelines, disconnection of flowlines and umbilicals from underwater trees, as well asThe intervention included the cleaning of manifolds and pipelines, disconnection of flowlines and umbilicals from the subsea trees, as well as the recovery of risers and midwater bows. In addition, moorings were removed from the FPSO and its towing was managed.
The entire process was carried out using remote systems from the operations base in Aberdeen, with additional support from Haugesund, Norway. The use of in-house tools eliminated the need for direct human intervention underwater, improving safety levels and operational efficiency.
A methodology that redefines decommissioning
The disconnection of the reel and the installation of blind flanges represent key technical achievements. These actions, which normally required divers, were executed in an automated fashion using solutions developed in-house by DeepOcean.
The customized tools allowed us to carry out the entire campaign without direct human intervention, with exemplary results.
Robin Mawhinney, managing director of DeepOcean UK, said.
Gryphon Alpha: three decades of offshore history
Put into service in the 1990s, the FPSO Gryphon Alpha was the first floating unit with permanent mooring built for the North Sea. Initially operated by Kerr McGee, it was later taken over by Maersk Oil and, since 2018, has been owned by TotalEnergies.
Although estimated to have a useful life of ten years, the asset far exceeded expectations, producing more than 250 million barrels of oil equivalent in thirty years.
With most of the work completed, DeepOcean expects to complete the retrieval of the remaining moorings and final risers before the end of the year.
Source and photo: DeepOcean