Shelf Subsea have been called to several jobs requiring urgent interventions. In 2020 we were called to assist in an FSO whose offtake line was rendered in-operable due to a dislodged subsea connecting Manifold structure and connecting spools and pipeline. The requirement was to implement a temporary solution to quickly re-establish offtake of fluids to normalise field production operations to fill the period whilst a permanent solution was separately underway.
Urgent and Emergency subsea interventions are never ‘standard’ jobs -each situation brings its own unique challenges. This requires a special combination of skills that Shelf Subsea uniquely have. Ready ‘to go’ in-house resources covering core competencies and assets at the ready such as Vessels, ROVs, Survey, Divers and experienced project managers and engineers. Moreover, a sense of urgency, ‘can-do’ attitude, the ability to explore and come up with creative solutions, on top of a wide range of experience, skill sets, and disciplines that can be brought together to meet unique challenges at end.
Shelf Subsea in conjunction with a specialist engineering house were able to deliver a solution that involved the installation of a temporary flexible line from the FSO to subsea manifold to allow condensate to offload and Field production to continue, while replacement permanent flexible lines were sourced.
The project was notable for the complexity of the of the effected and involved parties, and mobilising during COVID lockdowns and restrictions.
In the lead up to the project despite extensive and extremely complex international travel and vessel movement restrictions Shelf were able to mobilise an international crew of skilled divers, ROV operators and offshore construction engineers. In addition, extensive specialised and bespoke equipment and consumables were sourced.
Mobilising an international project and marine crew during COVID the team over the course of 27 days performed 37 Saturation bell runs, 9 Air Dives, 37 ROV dives. 300m of 3” flexible hose and 20 riser clamps were procured for the project (through specialist engineer house) and was installed from FSO turret 100m over mid water arch, a further 70m to touchdown point, and a further 45m to subsea riser flange. The PLET/Gravity Base and mid water arch were relocated, and fresh holding clamps installed on the manifold pup piece on the PLET/Gravity Base using a special subsea drill, and new rigid spool piece installed. Some repair and maintenance on existing pipeline as well stabilisation of the 3” line on the seabed.
The project finish without incident and the FSO was successfully able to continue operations and the field kept producing.
“KNOC highly appreciates DSV SOUTHERN STAR for excellent job your team have done in the Rong Doi – MV12 Riser Repair Project. Your outstanding efforts in execution of this crucial works and distinguished performance will undoubtably aid to the successful completion of this challenging Project”
August 2020 – Mr Lee Taek Seop – MD KNOC Vietnam Office