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Sub-zero temperatures, high seas, strong winds and low daylight present their own unique challenges for the offshore sector. Conditions can be tough in the frontier areas opening up in the Norwegian Sea and the Barents Sea—which may call for specialized equipment and robust offshore personnel.

A leading back deck machinery specialist supports the industry by designing and engineering equipment that can be manufactured to cope with the harsh conditions and withstand working in temperatures down to -45°C. The cold temperatures can affect the metal, electronic controls and the viscosity of the hydraulic fluids—so equipment has to be designed specifically for these climates.

The Environment

The Arctic is one of the coldest places with temperatures capable of reaching -70°C (-94°F) during the winter, when there is also 24 hours of darkness and ice grows to cover 80% of the ocean surface. During the summer months the weather remains cool with the sun sitting low in the sky and in the autumn it barely rises above the horizon. The air sitting above the ice is so cold that it is not able to hold much moisture so in some places rain is minimal.

An aerial view of the Arctic would look as if it covers quite a large area—in actual fact the basin is fairly small as over a third of it is continental shallows. The continental shelf north of Eurasia underlying the East Siberian, Laptev and Barents seas reaches 500 to 1,800 km beyond the coastline. It is believed the Arctic region could account for almost a quarter of the world’s undiscovered petroleum resources, covering an area of 14,056,000 km² and its deepest part: Arctic basic at 5,625 m.

Environmental and climate considerations have always been an integral part of Norwegian petroleum activities. A comprehensive policy instrument scheme safeguards environmental and climate considerations in all phases of petroleum activities, from licensing rounds to exploration, development, operation and cessation. The strict restrictions on flaring under the Petroleum Act contribute to keeping the general flaring level on the Norwegian Shelf low, compared with the international level.

Norway introduced a C02 tax in 1991, which has directly led and encouraged companies to invest in technological development and measures have yielded emission reductions. Authorities and industry have worked closely on ensuring they could reach zero harmful discharges to the sea. Norway places a strong emphasis on the environment and the Norwegian petroleum sector maintains a very high environmental standard.

Why the interest in exploring the Norwegian Sea and Barents Sea?

After forty years, an agreement was drawn up between Russia and Norway in 2011. The aim was to overcome and resolve the border dispute in the section of the Barents Sea that both countries were claiming, which resulted in an additional 88,000 km² put under Norwegian jurisdiction.

These new opportunities come with their own challenges, and there are areas within the Norwegian Sea and Barents Sea that are being deemed as new frontier territories, for example in the Norwegian Sea the frontier area applies to the deepwater section(s) in the northernmost region. Companies looking to explore these opportunities know from previous experience that they will undoubtedly be presented with both technical challenges and uncertainty during the exploration process;however, major new discoveries could be made as a result.

Oil and gas reserves in the Barents Sea and Russian Arctic have historically been much less explored. Although less explored, the region is gaining more attention. Still considered an immature petroleum region, there has been some production: Snøhvit field started producing in 2007 and Goliat field’s production was due in 2015.

Complexities of working in the Arctic latitudes

Exploration in Arctic conditions comes with a range of complexities, which is demonstrated by the Russian Shtokman field that was discovered in 1988. The field is positioned 283 km offshore, where the Arctic conditions have impeded the field’s development even though it is one of the largest gas fields.

The Johan Castberg project, covering Skrugard and Havis fields, where reserves were discovered in 2011 and 2012 in water depths of 373 m and more than 200 km offshore, has to deal with the complexities of the fields; in order to address the difficulties faced, it has been proposed the development would use a semisubmersible production unit in combination with an export pipeline.

Operations in these extreme and harsh conditions continue, all adding to Norwegian output.

A harsh and unforgiving environment coupled with adverse weather and high seas are to be expected within these waters. In the Norwegian and Barents Sea, exploration and production will require both resilient offshore personnel and assets. These new frontiers can be a challenge for any company to confront.

ACE Winches is no stranger to providing equipment and personnel to support clients working in similar extremely harsh and cold conditions in Alaska and offshore Russia—Sakhalin Islands. The company has previous experience in designing, engineering and manufacturing back deck machinery along with providing offshore personnel destined for offshore projects.

The company previously received a contract to support the load out of one of the world’s largest offshore platform topsides on the Sakhalin II project. The project was located offshore from the Sakhalin Islands, which also experiences and manages operations in colder temperatures—in the winter the north can get down to -24°C and temperatures have been recorded down to -54°C. The scope of work included the supply of a 120te topside load-out winch package comprising of 120te Drum Winches, 132k diesel HPUs (hydraulic power units), wire rope package and a team of personnel deployed.

In Newfoundland and Labrador, Canada, the company supplied a hire contract to supply a Gravity Based Structure (GBS) installation, working from the dry dock at the Bull Arm construction site for the installation project.

The Hebron field will be developed using a stand-alone concrete GBS. The reinforced concrete structure is designed to withstand sea ice, icebergs and meteorological and oceanographic conditions. The GBS will be supporting an integrated Topsides deck including living quarters and drilling/production facilities.

Hebron field lies offshore Newfoundland and Labrador, Canada, in the Jeanne d’Arc basin, 350 km southeast of St. John’s.

The scope of work included the supply of the following:
• Five 75 Tonne WLL CT Hydraulic Drum Winches
• Six 220kW Safe Area Diesel Hydraulic Power Units
• Six 150 Tonne WLL Safe Area Running Line Monitors
• A Wireless RLM Display Panel
• Four 75 Tonne WLL Swivel Head Fairleads
• A 75 Tonne WLL Roller Box Fairlead
• Operational personnel.

ACE Winches secured a contract to design, engineer, manufacture and commission an electrically driven 8-point mooring spread to be mobilized to an oil spill containment vessel, the equipment was mobilized for use in the Arctic region of Alaskan waters. The winch package was specially designed, engineered and manufactured at the company’s facilities in northeast Scotland, and capable of operating in temperatures as low as -45°C.

The winches, certified to ABS, were tailored to meet the mooring requirements of the barge and in accordance with the ABS code for the construction and equipment of mobile offshore drilling equipment.

Due to the nature of the mooring conditions, the mooring lines required the fairleads to be low ‘in the water’ (below ice level); however, this would then cause restrictions whilst the barge was under tow, and possible ice damage to the system. The solution involved the design team developing a unique travelling fairlead system, which brought the fairleads out of the water when the vessel was under tow, reducing vessel drag, improving tow efficiency and mooring stability.

The scope of work included four 100 Tonne WLL Electric Double Drum Winches, one Fixed Upper Turn Down Sheaves, one Sliding Travelling Fairleads and four Electro Hydraulic Power Units.