Rotech Subsea wraps up cable de-burial and post-lay trenching in North Sea

Rotech Subsea has completed de-burial and post-lay trenching works on a key interconnector cable in the southern North Sea.

According to Rotech, the company carried out the work for a leading cable player.

The company’s TRS2 controlled flow excavator was mobilised in Q2 of 2021 to complete the de-burying of damaged cable to allow for an omega loop to be laid then trenched in.

The cable was de-buried to a minimum of three-metre depth with the newly laid cable trenched to client specification of two metre ToC.

The company’s 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 said.

The TRS2 subsea spread of equipment was mobilised on a support vessel and the job was finalised in June 2021.

“Rotech Subsea were delighted to have been selected for this critical interconnector IRM scope. Our TRS2 controlled flow excavator was selected to carry out the scope of work due to its high flow capabilities of 8000 l/s allowing for a large amount of material to be dispersed and also allow for the trench to remain open for sufficient time to pull out the cable”, said Rotech Subsea director of Subsea, Stephen Cochrane.