Norwegian oil major Statoil has begun the upending procedure for the massive Aasta Hansteen substructure off Norway.
Statoil posted an image on social media channels on Tuesday, showing the spar substructure partially submerged.
The company said that the upending of the massive Aasta Hansteen substructure began on Monday in Klosterfjorden on the west coast of Norway. The spar substructure was towed to the upending location, where water was let into the soft bottom tank.
In just a few hours the substructure tilted 26 degrees as planned. Statoil added that 50 million liters of water would be pumped into other tanks of the hull over the next few days, making the upending complete.
When it is all said and done, 160 meters of the 200-meter-long substructure will be submerged under water.
The substructure for the world’s largest spar platform arrived from Hundai Heavy Industries’ facility in Ulsan, South Korea to Norway on June 18, 2017, after a 14,500 nautical mile journey at sea. The structure weighs a whopping 46,000 tonnes and was transported on the huge heavy transport vessel, Dockwise Vanguard.
The substructure and the Dockwise Vanguard have been together from April 4. The two parted on June 28 when the substructure was floated off the transport vessel in Sunnhordland.
Apart from the lower hull, Hyundai Heavy is in charge of building the topsides. According to Statoil’s estimates, the topsides will follow the spar in about four months. When it is completed, the gas platform will then be towed to the Norwegian Sea and the Aasta Hansteen field during 2018.
The Aasta Hansteen platform will be Norway’s first spar platform in production. Spar is a cylindrical, partially submerged offshore drilling and production platform that is particularly well adapted to deepwater.
The gas discovery -previously named Luva – is situated at a depth of 1,300 meters in the Vøring area, 300 kilometers from land.
Statoil is the operator of the field with Wintershall, OMV, and ConocoPhillips as partners.
Offshore Energy Today Staff