Statfjord C - 11,4'' Flexible Riser
SubseaCutter saves two and a half days vessel time and the environment when completing 22 cuts on a 11,4'' Flexible Riser
Scope of Work
Control Cutter was contacted by Equinor to conduct a subsea operation on a Statfjord C satelite where a 11,4’’ flexible water injection riser was to be decommissioned.
The operation required 22 cuts to be completed on the 399,5mm OD flexible riser and a limited window was given to the operation due to vessel schedule.
The SubseaCutter was deployed and operated by the ROV without any umbilical from the surface. Using the same blade on all 22 cuts, the operation was carried out in two rounds where the first 18 cuts were done without the tool surfacing.
Two and a half days vessel time was saved compared to conventional tooling from the SubseaCutter's rapid cutting time of five minutes per cut and no surfacing of the tool in between the cuts. Conventional tooling, saw or diamond wire, normally require two hours per cut on a 11,4"" flexible riser.
Flowlines consist of several layers of different types of polymers, using diamond wire or saws, will release small plastic particles into water causing environmental damage to the eco system.
As the SubseaCutter only separates the flowline using a cutting blade, no particles are released into the eco system, making it a more eco-friendly alternative.