Nexans Designs Power Umbilicals for OneSubsea

OneSubsea, the subsea technologies, production and processing systems division of Schlumberger, has contracted Nexans to design and supply two 120-km (75-mi) power umbilicals for a subsea multiphase compression system at Norske Shell’s Ormen Lange gas field in the Norwegian Sea.

The French player in the cable and optical fiber industry said that the system will help extend the production life of the Ormen Lange field, Norway’s second-largest gas field that currently supplies 20 percent of the UK’s gas needs.

Located in the Norwegian Sea, the Ormen Lange gas field produces about 70 million cubic meters of gas a day that is piped to the onshore Nyhamna processing plant. It is then purified and transported to the UK through one of the world’s longest subsea pipelines, which covers about 1,200 km.

The OneSubsea multiphase compression system is an innovative technology developed to boost the gas pressure. OneSubsea and its Subsea Integration Alliance partner Subsea 7 are supplying and installing two 16-megawatt (MW) subsea compression stations tied into existing manifolds and pipelines at a water depth of 850 meters. The system will be powered and controlled from the Nyhamna onshore gas processing plant, located 120 km away from the subsea location.

Nexans is delivering the power umbilicals that will integrate all the 52-kV electrical power, hydraulic and fiber optic elements required to power and control the compressor station.

The Ormen Lange power umbilicals will be designed and manufactured by Nexans Norway specialist facility in Halden. Delivery and installation by the new Aurora cable laying vessel is scheduled for 2023.