The Castoro Sei is a column stabilized semi-submersible

Semi-submersible

A semi-submersible is a specialised marine vessel with good stability and seakeeping characteristics. The semi-submersible vessel design is commonly used in a number of specific offshore roles such as for offshore drilling rigs, safety vessels, oil production platforms and heavy lift cranes.The...

 pipelay vessel. She has an overall length of 152 metres (498.7 ft), a width of 70.5 metres (231.3 ft) and a operating draught of 7.8 to 15.5 m (25.6 to 50.9 ). The Castoro Sei is equipped with 2 rotating gantry cranes 134 tonnes capacity and three 110 tonne pipe tensioners for pipelaying. She provides accommodation for 330 persons.

She was built in 1978 by Fincantieri

Fincantieri

Fincantieri - Cantieri Navali Italiani S.p.A. is a shipbuilding company based in Trieste, Italy. It was formed in 1959 and is the largest shipbuilder in the Mediterranean, and one of the largest in Europe...

, and owned and operated by Saipem

Saipem

Saipem S.p.A. is an Italian oil and gas industry contractor. It is a subsidiary of Italian energy company Eni, which owns approximately 43% of Saipem's shares. Saipem has contracted for designing and constructing several pipelines, including Blue Stream, Greenstream, Nord Stream and South...

. Her port of registry is Nassau, Bahamas

Nassau, Bahamas

Nassau is the capital, largest city, and commercial centre of the Commonwealth of the Bahamas. The city has a population of 248,948 , 70 percent of the entire population of The Bahamas...

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The Castoro Sei has been used for laying a number of pipelines in the Black Sea

Black Sea

The Black Sea is bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and the Aegean seas and various straits. The Bosphorus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects that sea to the Aegean...

, North Sea

North Sea

In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...

 and Mediterranean Sea

Mediterranean Sea

The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...

, including Blue Stream

Blue Stream

Blue Stream is a major trans-Black Sea gas pipeline that carries natural gas from Russia into Turkey. The pipeline has been constructed by the Blue Stream Pipeline B.V., the Netherlands based joint venture of Russian Gazprom and Italian Eni. The Blue Stream Pipeline B.V...

, Greenstream, Medgaz

Medgaz

Medgaz is a submarine natural gas pipeline between Algeria and Spain.-History:The idea of building a direct gas pipeline between Algeria and Europe arose in the 1970s. However, the technical limitations at that time prevented the construction and operation of an ultra deepwater gas pipeline...

, Trans-Mediterranean

Trans-Mediterranean Pipeline

The Trans-Mediterranean Pipeline is a natural gas pipeline from Algeria via Tunisia to Sicily and thence to mainland Italy. An extension of the TransMed pipeline delivers Algerian gas to Slovenia.-History:...

, Europipe II

Europipe II

Europipe II is a natural gas pipeline from the Kårstø processing plant north of Stavanger to a receiving terminal at Dornum in Germany. It became on stream on 1 October 1999.-Route:...

, and BBL

BBL Pipeline

The BBL Pipeline is the first natural gas pipeline between the Netherlands and the United Kingdom.-History:Laying the pipeline between the North Holland compressor station at Grasweg in Anna Paulowna and Bacton Gas Terminal started on 14 July 2006...

 pipelines. The vessel is also deployed for laying the Nord Stream pipeline in the Baltic Sea

Baltic Sea

The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...

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