Preparations for welding together two of the three sections of the 1,224 km pipeline through the Baltic Sea have now started. They will be welded together on the seabed off the coast of Finland in a complex process expected to take about two weeks. Connection of the Gulf of Finland section and the Central section at a sea depth of approximately 80 m has now begun.
The technical completion of the first of the twin pipelines will be achieved in June, when the final section is welded onto the pipeline off the Swedish island of Gotland. Construction of the second of the twin pipelines is scheduled for completion in 2012.
When both of Nord Stream’s twin pipelines lines are completed in late 2012, Nord Stream will have the capacity to transport 55 Bcm/a from Russia to Europe, enough to supply 26 million homes.
Pre-commissioning activities are already underway; for the Gulf of Finland and Central section cleaning, gauging and pressure-testing have been successfully completed, and the pressure test for South Western section now follows.
On the site of the German landfall all piping has been completed and successfully pressure tested. For the Russian landfall site pressure testing is expected by the end of May after completion of all welding works. Further rigorous testing will be carried out on the whole system before it becomes operational in the last quarter of 2011.
Hyperbaric tie-ins of the sections will be carried out by Technip SA using its new-built diving support vessel, the Skandi Arctic. The tie-in process will take place on the seabed and welding operations will be remotely controlled from the diving support vessel with divers assisting and monitoring the subsea construction work.