Credeblug and Tecnalia have teamed to improve the maintenance and repair operations carried out on underwater power cables. The end result: the manufacture and validation of s cutting and clamping tool, designed to secure one end of a cable after it has been cut, aiming to save time and money.
“This functionality has been called for by offshore cable repair teams all over the world since such operations began in the 19th century," said Joannes Berquè, a TECNALIA researcher. "To this day, current cutting tools mean that the ends of the cable drop off after they have been cut. The repair operation then requires an additional search for the end of the cable with another tool, usually a cable clamp, which gropes around the seabed in poor visibility, which is challenging even for the best equipment. In rough seas, this additional search and lift operation can take several hours, with a knock-on effect on the entire repair operation."
“The Cabletool project is a new step in Credeblug's strategy to develop specific loading tools for the offshore sector," said Asier Susaeta, GM Credeblug. "We already have technology capable of handling large loads up to 1,000 meters deep, so this new development is a step forward in terms of functionality. We believe that by reducing submarine cable mooring, cutting and recovery times, we offer differentiating technology in the market and certainty in this type of operation.”
Credeblug's tool combines a cable grip and a cutter in a single hydraulic tool. The grab also includes lighting and vision systems for cable tracing and a better grab positioning. The long arms of the grab is designed to make it easier to locate and retrieve cables from the seabed, as the arms make it possible to probe much deeper into the seabed where the cable is normally buried. Once the cable has been grabbed and secured under water, the guillotine cutter is activated. The most critical feature is that the grab hangs firmly onto the cable after the cut, rather than dropping the ends onto the seabed. The cut end is then safely raised by the grab and immediately handed over to the deck crew to prepare it for the splicing team.
After three years of development and testing at the Credeblug plant in Azpeitia, in March 2023 they were successfully able to carry out their validation at sea, in the port of Bermeo (Bizkaia), as part of an R&D project supported by the Basque Government's Hazitek Program (WIND2GRID). The gripping, cutting and clamping tool is now available for fully shielded underwater power cables up to 270 mm, and larger sizes can be manufactured on request.