General – interconnector
Rotech Subsea has completed major de-burial and post-lay trenching works on a key interconnector cable in the southern North Sea for a leading cable player.
Rotech Subsea’s next generation TRS2 controlled flow excavator was mobilized in Q2, 2021 to complete a scope of work consisting of de-burying damaged cable to allow for an omega loop to be laid then trenched in. The cable was de-buried to a minimum of 3m depth with the newly laid cable trenched to client specification of 2m ToC.
Rotech Subsea – and their more powerful Controlled Flow Excavation (CFE) kit – was called in after older Mass Flow Excavation (MFE) technology had struggled to de-bury the cable on an earlier repair.
Rotech Subsea’s TRS2 subsea spread of equipment was mobilized on a support vessel, with the job completed in June 2021. The Rotech CFE spread operated in water depths of up to 42m LAT. Soil conditions in the area were sand with the presence of clay in some areas.
The TRS2 successfully de-buried the cable to client specification with one pass at progress rates of 1m/min – 3m/min. Burial of the cable was successfully achieved in two passes at a rate of approximately 4m/min. The exceptional performance capabilities of the TRS2 led to a saving on total project costs for the client, who Rotech Subsea looks forward to collaborating with again.