Over 30 years, it is estimated that the Sakhalin facility, located off the coast of Sakhalin Island in Russia’s Far East, will produce the equivalent of Russia’s total crude oil exports for more than one year (1 billion barrels) and its total gas sales to Europe for five years (500 billion cubic meters).

A consortium of companies, including Royal Dutch Shell and Mitsubishi, is investing billions of dollars to build offshore platforms and onshore processing plants along Sakhalin’s east coast.

Norwegian company Aker Kværner is in charge of building the base structures for two offshore platforms, which is no easy task, according to senior engineer for safety and reliability Bjørnar Langelo.

“The fields are located in a very difficult area,” he said.

“There is a high risk of earthquakes, temperatures range from 39C below freezing to a warm 28C and in winter, pack ice comes crashing in.”

One major challenge for Aker Kværner was to protect the concrete structures, as well as the pipes transporting the oil and gas from under the ocean floor, from potential fires and explosions.

This was a particular concern because of the high level of seismic activity in the area, making earthquakes a potential threat.

“If a fire occurs on the platform, it could spread down into the shaft and damage the structure,” Langelo said.

“Likewise, a gas leak on the platform could enter the shaft, blend with oxygen in the air and cause an explosion.”

Aker Kværner asked Viking to develop jet-fire seals for the project that would delay the fire.

At its premises in Krokstadelva, 60km west of Oslo, the company designed and produced 156 jet-fire seals, around 1m high and 2.5m wide.

The challenge was to create a product that was not only resistant to fires and explosions but also sufficiently flexible, according to Terje Fossesholm, manager of the offshore projects department.

“Usually, jet-fire seals are designed for small movements, between 10mm and 50mm, but because of the earthquake risk at Sakhalin, they had to be able to withstand movements of 500-600 mm.”

The result was large reinforced, synthetic rubber seals.

Twelve Trelleborg employees travelled to Russia last year to install the jet-fire seals on the concrete structures. The shafts are now in place on the ocean floor waiting to be connected to the platform.

• Weather conditions are extreme, with temperatures plummeting to –39C or rising as high as 28C.

• The area has a high level of seismic activity, making it prone to earthquakes.

• There is fog for most of winter, often making it difficult to land by helicopter on the platform.

• Once production is fully in progress, more than 200 employees will work on the platforms.