More than a million tons of steel will be used, and the production of pipes will lay claim to a third of the world's total production capacity for this type of pipeline.
100,000 pipes in all will be painted inside and covered with asphalt and concrete before installation in the North Sea. This will require over a million tons of concrete and 25,000 tons of steel reinforcements.
Two of the world's largest pipeline-laying vessels, Stolt Offshore's LB200 and Solitaire from Allseas, will lay the 1,200 kilometer long pipeline, Langeled, between Aukra and Easington, in addition to the pipelines from the field to the onshore processing plant.
LB200 has started the pipelay from the Sleipner platform in the North Sea and is heading south towards Easington. Solitaire will start laying the first 33 kilometers of Langeled and the production lines from Nyhamna in the beginning of June. The main part of the northern leg of Langeled will be installed next year.
Hydro has designed the Langeled pipeline to carry more than 70 million cubic meters per day – meaning the Easington terminal could be providing more than 20 percent of UK gas needs for decades to come.
Ormen Lange project well underway
FMC Kongsberg are currently manufacturing production equipment which will be placed on the seabed in the fall of 2005, while at Grenland-Group's yard in Tønsberg, the enormous underwater installations are taking shape, measuring 44 by 33 by 15 meters.
Just after Easter the manifolds was raised onto the template frames, and by August, the production stations will be installed 900 meters below the surface in the Ormen Lange field, using one of the world's largest lifting vessels, Thialf from Heerema.
The offshore-to-land pipeline has to pass the Storegga slide area with its rocky undersea landscape before climbing the steep escarpment.
To reduce the number of lengths of suspended pipeline, a complex route through passageways and with curves around obstacles has been chosen, so that the pipes can be laid in the least problematic terrain.
At the same time, the seabed is being prepared for pipe laying, both by excavating and filling aggregate.
Excavation at depths of 1,000 meters
The project is also receiving excellent assistance from Nexans' Spider technology. Two newly developed, remote-controlled underwater excavating machines will prepare the seabed before pipe-laying can begin on the steep slopes and broken terrain far below the sea surface.
This work will begin in April this year and continue until the autumn. Nexans also have the option to carry out localized pipe burial after installation in 2006 and 2007.
A pioneering project
The combination of great sea depths, highly irregular seabed terrain, strong underwater currents, sub-zero temperatures and challenging wind and wave conditions, have imposed considerable challenges on all parties involved in the project.
Development operator Hydro has mobilized significant portions of the Norwegian research community together with Norwegian industry in order to find solutions to problems far more complex than those previously encountered in oil and gas development projects on the Norwegian Continental Shelf.
Hydro is the development operator for both Ormen Lange and Langeled. Statoil has the management of the Langeled project in cooperation with Hydro.
Important milestones ahead
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