IOSS specialize in developing and implementing innovative engineered solutions for Light Well Intervention (LWI) to obtain increased oil recovery. Other subsea well operations using Island Offshore's dynamically positioned vessels can also be performed to replace drilling rigs, and hence offer reduced costs for subsea operations.
Worldwide there are close to 5000 subsea wells, and this number is growing with wells being completed in water depths down to 3000 m. The age of the subsea wells is also growing resulting in the need for riser less light well interventions to maintain the wells and increase oil recovery.
Cost saving is the main driver for performing riserless LWI operations from a monohull vessel, when compared to the same operations being performed from a drilling rig. These operations can be performed from a monohull DP-3 vessel whilst maintaining well control and access to the well bore via a subsea lubricator system, resulting in lower cost for intervention operations.
During the life of a well a number of planned or unplanned well interventions may be required. Activities may include; diagnostics, stimulation, surveillance, manipulation of equipment and repair of mechanical failure. The following identifies potential subsea intervention activities that can be accommodated from an LWI vessel.
- Mechanical failure downhole
- Mechanical failure in Xmas trees
- Flow assurance (e.g. scale, wax, hydrate)
- Reservoir monitoring (e.g. production logging)
- Reservoir work (e.g. zonal isolation, perforating)
- Well management (e.g. remedial stimulation)
- Recovered Wellhead, Conductor and Guide Base
Experience with various operators across the fleet has influenced the design of successive vessels and the incorporation of lessons learned has improved the safety and efficiency of the vessels and crews.