Rosneft adapts wellhead construction for Kara Sea wells

Aug. 31, 2020
Rosneft has provided an update on its current exploration drilling program in the Kara Sea offshore northern Russia.

Offshore staff

MOSCOWRosneft has provided an update on its current exploration drilling program in the Kara Sea offshore northern Russia.

CEO Igor Sechin, speaking to Russian President Vladimir Putin, said the company is drilling appraisal wells on the Vikulovskaya and Ragozinskaya structures in the Vostochno-Prinovozemelsky 1 & 2 license areas close to Novaya Zemlya.

Rosneft estimates cumulative reserves within these areas at almost 2 billion metric tons (2.2 billion tons) of oil and 3.7 tcm of gas.

Two ‘state-of-the-art’ drilling platforms are managing the campaign, both exported 1,500 km (932 mi) to the drilling locations in the Kara Sea.

The company’s supply vessels and tankers are provided fuel and water, and both platforms have been retrofitted with drilling equipment and ice monitoring systems to track iceberg movements, helping to avoid accidents in an ecologically sensitive area.

To cope with the relatively shallow water depth and the proximity to iceberg sources, Rosneft’s corporate R&D team decided to move the wellhead under the bottom surface in order to prevent damage from iceberg fragments.

This entailed drilling a 15-m (49-ft) shaft, almost 2 m (6.6 ft) in diameter, and designing a reamer bit 1.8 m (5.9 ft) in diameter.

Pilot borehole drilling has been completed at Vikulovskaya and blowout equipment has been lowered into the well. At Ragozinskaya, pilot borehole drilling has also been completed.

As a result of the OPEC+ agreement, Rosneft has had to temporarily reduce production from some of its Russian oilfields. “We are trying to rank the oilfields by efficiency in order to minimize the losses and we are primarily cutting production at low-efficiency depleted fields,” Sechin explained.

One example is the low-rate deposits on Sakhalin offshore northeast Russia, especially the Northern Chayvo field, which currently employs around 2,000 people.

Rosneft plans to use the remaining period of limited oil production this year to suspend wells and build new logistics infrastructure.

Currently crude from Sakhalin is supplied to the Komsomolsk refinery 600 km (373 mi) away. “We have now connected the plant to the main ESPO oil pipeline from the south, and we will shut down the old pipe and build an access to the sea terminal in De-Kastri.

“This way the project will be as environmentally friendly as it can, to the highest degree, and will have direct access to world markets and ensure a more reliable supply of the Komsomolsk refinery, which will certainly benefit consumers in the Far East.

“In a year and a half or two years, this field will return to regular operation, and for the time being, its personnel will be involved in rearranging routes, in the mothballing of wells and in other projects.”

Sechin also told Putin that Rosneft reached agreement with the Sakhalin-1 consortium members to compensate for the shortfall of associated petroleum gas used for fuelling the thermal power station in Okha.