Hughes Subsea Services (Hughes) secured a contract to deliver daughter-craft diving services for the Anasuria FPSO, positioned 175km east of Aberdeen.
Throughout the month-long campaign, the Hughes team provided support for mooring chain change out, executed the installation and removal of sea-chest blanks, and successfully completed a comprehensive inspection program.
Challenges
Short lead times in the project meant that it was not possible to secure all the equipment initially identified and the team had to be flexible in their approach for the project execution to be achievable.
The FPSO had to be under heating control to allow diving within the turret and to allow mooring chain change-out actions on the Anchor handling vessel.
Workscope
Provision of support services for mooring chain change out, installation and removal of sea-chest blanks, and conduction of a comprehensive inspection program.
Solution
The Hughes team supplied a dedicated rigging team to support the topside operations.
The dive intervention craft, Hughes Hunter, and tender vessel, Cardhu, were mobilised onto the Normand Frontier accompanied by a 45-member project team.
The vessel owners contributed WROV and survey support, while two independent telemetry systems facilitated real-time camera feeds from both the diver and topside team. As part of a comprehensive communications plan, OEG sister company Fern provided radios to all project vessels, and a dedicated Starlink feed was installed for optimised information distribution.
In addition to the FPSO scopes, the team, with assistance from the Normand Frontier, successfully deployed anode skids and concrete mattresses.
In order to maximise productivity in this project, the Hughes team conducted all diving operations using nitrox, ensuring maximised bottom times and reducing the number of personnel required to deliver the scope.
The project was delivered efficiently, safely, and ahead of schedule.
Graeme Shepherd, Project Manager at AOC:
Hughes Subsea has played a pivotal role in the recent Mooring Chain Changeout and associated topside and subsea work scopes for AOC, which was in integral part of AOC’s ongoing asset life extension programme aimed at extending the operating life of our FPSO.
Throughout the duration of this project, the level of professionalism and collaborative teamwork exhibited by Hughes Subsea alongside our other partners and teams was nothing short of exceptional which was key to delivering the highly successful campaign.
