First Subsea and James Fisher Offshore – Subsea Tubulars Decom Tool testing milestone
First Subsea and James Fisher Offshore (JFO) have completed a significant testing milestone in their joint development of a combined Internal Cut and Lift tool, as part of an Oil and Gas Technology Centre (OGTC) co-investment initiative seeking to reduce the costs of decommissioning offshore.
A series of underwater cutting and lifting tests on tubulars supplied by Shell from their Brent facilities have been conducted at the National Hyperbaric Centre in Aberdeen, UK. The combined Internal Cut and Lift tool is capable of both cutting and lifting, in a safer, more efficient manner, compared to current technologies. When development is completed, it will provide the decommissioning sector with a standardised and efficient methodology for the recovery and removal of offshore structures which have been constructed using steel tubulars.
The Internal Cut and Lift tool comprises a JFO cutter and First Subsea ball and taper internal lift tool. During operation, the complete tool is lowered into the tubular. The gripping elements expand until the balls grip at any point inside the length of the tubular, ready to lift the cut tube, while the cutter is lowered to any position in the tubular. During the recent testing, the tool was used with steel tubulars ranging from 28” – 50” (71 – 127cm) diameter. It demonstrated that the cutting and lifting elements are able to expand and contract to pass through internal obstacles such as Talon connectors. Positive cut identification combined with the secure lifting element allows an offshore team to perform the lift in one simple operation rather than multiple trips into the tubular to check the cut is clean, ensuring there are no snags during retrieval. The First Subsea connector is easily disengaged once the steel tubular is recovered, and the complete tool removed in preparation for reuse.
Using an Internal Cut and Lift tool streamlines an operation that traditionally would have required a lifting spread and a cutting spread, which currently requires two disciplines, multiple vendors, technicians and bunk space, large deck space requirement and multiple interfaces. The combination of the cutting and lifting technologies provided by a single provider, James Fisher Offshore, not only reduces the time required offshore but simplifies the marine operational program.