ZUG, Switzerland – All three sections of the first Nord Stream 1,224-km (760-mi) gas pipeline through the Baltic Sea have been laid, and will be joined this summer off the coasts of Finland and Sweden.
The new pipeline system will start transporting gas from Russia directly to the European Union during 4Q 2011. Construction of the second pipelines should be completed next year.
When both lines are in place in late-2012, Nord Stream will have capacity to send through 55 bcm/yr (1.9 tcf/yr).
The first of the pipelines is designed to operate without an intermediate compressor station, but with three different design pressures and pipe wall thicknesses as the gas pressure varies over the journey from Russia to landfall in Germany.
Connection of these three sections will be performed at the two offshore locations where the design pressure changes from 220 to 200 bar (3,191-2,901 psi) and from 200 to 170 bar (2,901-2,465 psi).
The Gulf of Finland section and the central section will be connected off the coast of Finland in spring in a water depth of around 80 m (49.7 mi). During the summer, connection of will be effected on the central and southwestern sections off the coast of Gotland, Sweden, in a water depth of around 110 m (361 ft).
All three sections will be gauged and pressure-tested prior to being joined together and linked to the landfalls in Russia and Germany.
Pre-commissioning for Line 1 is under way. For the offshore sections 1 and 2, cleaning, gauging and pressure testing have been completed. The pressure test for section 3 will follow mechanical completion of pipe laying.
At the German landfall, all piping has been completed and pressure tested. At the Russian landfall, pressure testing should be completed by end-May after completion of all welding works. Further testing will follow on the entire system before it becomes operational late this year.
The pipelay vessel which laid most of Line 1, Saipem’s Castoro Sei, is heading to Turku in Finland for extensive maintenance before resuming pipelay for Line 2, scheduled for completion in spring 2012. Allseas’ Solitaire will again lay the Gulf of Finland section.