- 100,000 tonnes of rock
- 160,000 tonnes concrete structure
It’s not every day that Van Oord installs an offshore Gravity Based Structure (GBS). ‘But when the chance arises, we are ready to take it. Installing a 160,000 tonnes concrete structure requires a high degree of precision. Despite the extremely tight scheduling and complicated work, Van Oord’s first priority – to work safely – was never in question’, says Project Manager Rob de Jong. Van Oord demonstrated its expertise in 2012 when working with its Russian partner Sovcomflot to tow a concrete platform foundation and lower it to the seabed.
New oil and gas field
Discovered in 1989, the Arkutun Dagi oil and gas field is located 25 kilometres off the east coast of Sakhalin Island in Russia. It’s the third and final field being developed as part of the larger Sakhalin 1 project. This project is meeting the challenges of the world’s growing energy demand: the fields are estimated to hold potential recoverable resources consisting of 2.3 billion barrels of oil and 485 billion cubic metres of gas. Thanks to Van Oord’s activities, the Arkutun Dagi field is being developed using a GBS to support the integrated topside structure, which includes a drilling rig, processing facilities, living quarters, and associated utilities.
All operations were closely monitored from the bridge of the Offshore Support Vessel. We only had one chance to do this right. I had full confidence that the right people were offshore to make the right decisions if and when required. On behalf of the VOSCF Joint Venture, a total of 117 persons were involved in Engineering and Operations Management.
The platform’s GBS, which measures 135 metres by 100 metres wide and 55 metres high, has a total weight of 160,000 tonnes. Three ocean-going tugs, an offshore support vessel and construction support vessel were needed to tow it to its designated location. This 1,900-kilometre trip took 14 days. The preparations took two years, but the actual work of towing and installing the GBS lasted only a month. After immersing the GBS onto the seabed, the hollow, sealed-off space was filled with grouting material. Finally, flexible fallpipe vessel Nordnes installed rock to protect the structure against erosion caused by the strong currents in this region. The unique abilities of the Nordnes were essential to avoid damaging the GBS and to line the rock up precisely with the edges of the GBS.
Van Oord and its Russian joint venture partner, Sovcomflot, won the 2013 Rusprix Award in recognition of their successful cooperation. The Russian Federation’s Embassy to the Netherlands created the award to recognise Dutch companies, organisations, and individuals who promote business and cultural relations with Russia. Van Oord and Sovcomflot were praised for having made an outstanding contribution to the strategic partnership between Russia and the Netherlands.
Start date2 June 2012 (excl. 2 years of preparation)
End date31 August 2012
LocationArkutun Dagi oil and gas field, east of Sakhalin
ClientExxon Neftegas Limited