Two riser platforms for pressure support have been installed in the system. The 16/11 S (now Draupner S) installation was placed on the pipeline between Kårstø and Ekofisk in 1984, and became operational on a regular basis in April 1985 as the first platform with a Norwegian operator.
The steel jacket for this facility was positioned in 75 metres of water 160 kilometres from the Norwegian coast in the autumn of 1983. Its topside and associated equipment were lifted on in the summer of 1984, and people could move into the living quarters.
Ekofisk 2/4 S, the second platform, was also installed in 1984 at the point where Statpipe joined the Norpipe system from Ekofisk to Emden. Owned by the Statpipe partnership, this installation was remotely operated from the Ekofisk centre with Phillips Petroleum as operator.
Its job was to ensure that dry gas flowing from Kårstø to continental Europe reached its destination by boosting gas pressure with the aid of compressors. These offset frictional losses in the pipeline. The platform was also used for inspection and maintenance of the pipeline.
To learn more, see: Gas via Kårstø
One of the first functions tested before the platforms became operational was transmission of a “pig” – a cleaning or inspection device pumped through the pipeline with the gas. Ekofisk 2/4 S was shut down in 1998, and its whole upper section was removed in 2001 with the aid of the Thialf crane barge. This was later scrapped at Lyngdal Recycling in southern Norway.
Statoil. Statpipe – en Europavei for norsk gass . Stavanger 1986, pp 96-98.
Aftenposten , morning edition, 31 December 1984. “Første plattform med norsk operatør”.
Ekofisk industrial heritage. Ekofisk 2/4 S.