Castoro Sei takes over laying Nord Stream pipeline in German watersProjects and Operations // October 5, 2010
Castoro Sei (C6) pipelay vessel reached German waters off the island of Rügen recently to continue laying the Nord Stream Pipeline.
Castoro Dieci (C10), a second, smaller vessel specially designed to lay pipes in shallow waters, has laid 27km of the pipeline in the Bay of Greifswald.
The C6 will recover this pipeline string and continue laying the pipeline towards Bornholm, Denmark.
“The construction of both lines in German waters is progressing faster than initially planned,” said Dr Georg Nowack, Nord Stream AG Project Manager for Germany. “We are almost four weeks ahead of schedule.”
The laying-sequence requires the pipeline to be laid down and picked up again at several places. This operation is called 'abandonment and recovery' (A&R).
On September 19, the C10 sealed the pipeline with a so-called A&R-head and lowered it down on the seabed. The C6 then pulled the pipeline back up into the vessel’s main production line. The A&R-head was removed and additional pipe segments welded to the pipeline string.
The C6 can lay up to 2.5km of the pipeline every day. By the second half of October, the C6 will have laid the remaining 55km of the 82km section in German waters. C6 started laying the pipeline in April this year in Swedish waters.
The second parallel string of the pipeline is currently being laid by C10. The pipelay vessel will conclude its work on the Nord Stream project after abandoning the second string east of Rügen. The C6 will continue laying the second line. When both strings are completed in 2012, each will be 1,224km long.
The Nord Stream Pipeline will then transport 55 billion cubic metres (bcm) of natural gas per year – enough to meet the needs of more than 26 million European households.