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Stavanger in the Norwegian North Sea, Gina Krog’s export pipelines design is production,” Andersen said. Through its

Gina Krog lays in 120m of water, 30km currently in follow-on phase, and seabed tie-back to Sleipner, a concrete gravity away from the Sleipner ? eld. Gina Krog preparation activities offshore are immi- platform from the 1990s, Statoil plans for spans Blocks 15/5 and 15/6 within pro- nent. Pipeline installation is scheduled in Gina Krog to use the older development’s

EPIC duction licenses (PL) 303, PL 048, PL 029 2015. Marine work, including tie-ins, will existing infrastructure.

and PL 029B. take place in 2016. However, accessing and processing

Operator Statoil said that since discov- First oil is scheduled for 2017, but such reserves usually requires many ery, the ? eld was brought up for develop- Andersen said the ? rst true test comes hours of dedicated, creative engineering ment consideration a number of times. well before then. work. Gina Krog is no exception.

Concepts were tabled each time until “The pipeline installation is actually Andersen explained that Gina Krog’s 2007, when oil and gas was proven in the the ? rst part, before the Gina Krog jacket platform, supplied by DSME and engi- neighboring development of Gina Krog itself come in,” he said. neered by Aker Solutions, will produce

Øst (originally Dagny East). Heerema is constructing Gina Krog’s oil and gas. Gas will be exported to the

A 100m-long oil column was proven 142m-tall jacket. It is the biggest the com- Sleipner A platform through a 27km, throughout the entire Gina Krog/ Gina pany has ever produced, and is scheduled 20in. export pipeline. A couple of hun-

Krog Øst structure through appraisal well to sail in April 2015. dred meters from Sleipner, a riser base drilling in 2008 and 2011. Project partner splits the 20in. pipeline in two 10in. riser

Design

Total said the ? eld, “contributes to the extension sections. The two 10in. risers renaissance of hydrocarbon production Gina Krog will be tied to Sleipner, will be pulled-in through existing J-tubes in the Norwegian North Sea.” Statoil allowing the two developments to enjoy a through to topside. Oil will be exported estimated reserves of 225MMboe, giving mutually bene? cial relationship. from Gina Krog through a 10in. insulated 600,000bo/d and 9 million cu. m/d gas. “The Gina Krog ? eld development is pipeline, terminating at a permanently-

Ramboll received the Gina Krog pipe- of one of several ? elds being developed moored FSO tanker. A ? exible riser con- line contract and ? ve subproject contracts in the vicinity of the Sleipner hub. This nects the pipeline to the FSO.

in March 2013, just months after being will assist in substituting some of the oil “Gina Krog requires gas for gas awarded January 2013’s Polarled contract. and gas from mature ? elds with declining injection in wells [to maintain reser- voir pressure]. This gas will be tapped through a hot tap connection to existing

Polarled pipeline project gas pipeline Zeepipe IIA. Zeepipe IIA is owned by Gassco and is part of the

Gassled pipeline infrastructure exporting gas to Europe,” Andersen said.

Beyond the delicate riser pull-in,

Andersen has identi? ed hot-tapping as another massively complicated operation.

Andersen said that the highly-com- petent Statoil, which has had a 10-year working relationship with Ramboll, is a very collaborative client, calling it a very open process.

Polarled

Crossing the Polar Circle, the 36in.- diameter Polarled pipeline runs 482km in water depths reaching nearly 1300m.

It will be constructed to transport gas volumes for planned and future develop- ments, including Aasta Hansteen, the world’s tallest spar platform. The pipe- line installation will be in 2015.

At least three Ramboll of? ces collabo- rated on the massive project: Denmark,

Norway, and India, where much of the drafting work took place.

The wall thickness is between 29-37mm – “very heavy indeed to start with,” he said. Due to the 1300m water

The Polarled pipeline, running from Aasta

Hansteen to the Nyhamna terminal.

Image from Statoil.

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