Category Archives: North Sea

The North Sea – a part of the Atlantic Ocean – is bordered by Norway and Denmark, Scotland and England, (and in the southeast) by the Frisian Islands and Germany, the Netherlands, Belgium and France.

MacGregor Provides Subsea Crane for ‘Island Intervention’

MacGregor, part of Cargotec, has won a contract to deliver a 250-tonne SWL active heave-compensated (AHC) subsea crane for the 120m construction vessel, Island Intervention. The crane was ordered by Marine Procurement Ltd, part of the US company Edison Chouest Offshore.

An existing vessel operated by the US/Norwegian partnership between Edison Chouest Offshore and Island Offshore requires greater lifting capability; a MacGregor 250-tonne SWL AHC subsea crane fulfils the upgrade requirements. Island Intervention is currently operating in the North Sea for the US/Norwegian partnership between Edison Chouest Offshore and Island Offshore. The vessel works in the offshore construction market and was delivered by Norwegian yard Ulstein Verft in 2011; its current lifting capacity is 140 tonnes.

“The vessel simply needs a bigger crane for the jobs that it undertakes,” says Frode Grøvan, Director, Sales and Marketing for Advanced Load Handling. “The order confirms the trend that we see of subsea modules getting larger and heavier, therefore requiring operators to equip their vessels with ever more capable cranes.”

“At MacGregor, we have the expertise necessary to ensure that retrofit projects like this run smoothly and successfully, with downtime kept to a minimum.”

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Helix ESG’s T1200 Trencher Completes First North Sea Oil and Gas Project

Helix Energy Solutions Group’s new T1200 burial and trenching unit is quickly establishing a positive track record following the completion of an oil and gas project in the North Sea. The T1200 features a 1,200hp jet trenching spread, capable of burying product in water depths to 3,000m (10,000ft).

T1200 was deployed to bury a 14km long (8.7 mile), 10 inch export pipeline that included a 3 inch piggyback methanol line. The project specialization called for the line to be buried 2m (6.5ft) deep, with one meter of covering fill. The subsea trenching unit’s water jetting system trenched and simultaneously buried the pipeline under 1.4m (4.5ft) of sand in a continuous run that took just 48 hours.

The successful project is the T1200’s first oil and gas operation, and proves the versatility of the asset which has also been deployed to trench and bury high voltage undersea cables used to transport electricity from offshore wind farms to onshore power stations.

The T1200, operated by Helix ESG’s robotics subsidiary, Canyon Offshore, performed its first trenching job in early July 2012 at the Sheringham Shoal offshore wind farm trenching and burying an approximately 700m (2,300ft) long power cable between the wind turbines. Out of the 80 sections required in the field, the T1200 trenched and buried 37.

The T1200 was built in the UK by Forum Energy Technologies’ Perry Slingsby Systems ROV brand. The T1200’s design was based around the time proven T750 trencher( also owned and operated by Canyon Offshore) but has over 50 percent greater power and the capacity to trench larger diameter products (36 inches) to burial depths of 3m (10ft) depending on soil strength.

Subsea World News – Helix ESG’s T1200 Trencher Completes First North Sea Oil and Gas Project.

Helix ROV Support Vessel Ready for North Sea

Helix Energy Solutions Group’s newbuild charter ROV support vessel, Grand Canyon, recently completed sea trials and is ready to begin operations in the North Sea. During the sea trials the vessel’s propulsion system, dynamic positioning system and all her cranes were tested.

The vessel recently completed its outfitting in Norway after the initial hull construction was completed in Turkey. Grand Canyon is capable of launching five ROVs at once and will be operated by Helix ESG’s robotics subsidiary, Canyon Offshore.

The vessel will be the new home for another recently completed asset, the T1200 trenching unit. Used primarily to bury large diameter power cables leading from offshore windfarms, the T1200 is also capable of working on oil and gas projects to bury production pipelines.

The Grand Canyon was designed to provide a high capacity, stable working platform for lay, burial and general offshore construction work while still retaining a shallow draft, which is crucial when operating close to the coastline, and common in the renewable energy sector.Grand Canyon’s DP3 capability allows her to operate in any sector, providing offshore support in a wide variety of roles.

The vessel’s deck structure is specifically designed to accept trenching and flexible pipe or cable lay systems for safe and efficient mobilizations. A key focus throughout the design and build of Grand Canyon was to optimize the vessel and equipment design to facilitate efficient mobilizations.

Helix ROV Support Vessel Ready for North Sea | Offshore Energy Today.

Total sends fire-fighting ships near N.Sea gas leak

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By Oleg Vukmanovic and Muriel Boselli
LONDON/PARIS | Thu Mar 29, 2012 9:08am EDT

(Reuters) – France’s Total sent fire-fighting ships to wait near the scene of a gas leak from its North Sea Elgin platform, which has created fears a large gas cloud could explode.

The company said the gas was originating thousands of meters below the sea bed, which engineers said might mean that a relief well – one possible option to stop the leak – could take months to drill.

“The leak is from a (gas) well that was plugged one year ago and from a rock formation in about 4,000 meters depth,” a company spokeswoman in Aberdeen said on Thursday.

A flare needed to relieve pressure in the platform by purging excess gas has continued to burn less than 100 meters from the leak, and engineers said changes in wind and weather could lead to an explosion.

“The wind is pushing the gas cloud in the opposite direction (from the platform). At this time, the circumstances are rather favorable,” Jacques-Emmanuel Saulnier, head of communication at Total said in an interview published on Total’s website.

“A gas cloud is always a fire hazard,” he added.

Total kept two fire-fighting ships in a state of readiness outside a two-mile exclusion zone, which was set up to protect marine traffic, a Total spokeswoman said.

The company has also brought in a robot vessel, not yet deployed, to scan the sea bed for signs of spillage, she said.

Total has not yet found a way to stop the gas leak. A team of international engineers assembled by the embattled French oil company are drawing up plans to tackle the leak and prevent the flare from coming into contact with the gas cloud, the spokeswoman said.

The platform is currently off limits to the engineers, however, given the toxic and explosive plumes pumping out of the wellhead.

The leak started on Sunday and forced the evacuation of all 238 workers from the platform, which sits in waters less than 100 metres deep and 240 km (150 miles) off the east coast of Scotland.

PRESSSURE SEEN FOR RELIEF WELL

Total warned on Tuesday it could take six months to halt the flow of gas. The company previously stated it hoped the leak would die down from natural causes as reservoir pressure drops.

“What we know is that the leak is not coming from a well dug by Total but from a naturally occurring pocket of gas located just above one of our wells,” said Total’s Saulnier.

The depth of the non-producing reservoir that is feeding gas to the Elgin platform via compromised layers of piping suggests, however, there is more gas present rather than less, piling pressure on Total to drill a relief well, an engineer with knowledge of the matter said.

Relief drilling would require boring through 4 kilometers of rock with painstaking mathematical precision, because it must intercept the gas pocket at exactly the right point, requiring constant alterations in course, the engineer said.

The leak, one of the biggest in the North Sea for decades, could well inspire tougher safety regulation in due course, according to experts. Britain’s health and safety watchdog said it was considering launching an investigation into the incident, while union officials said the frequency of offshore safety lapses had become intolerable.

Memories are still raw in the North Sea industry of the Piper Alpha platform fire 24 years ago, which killed 167 people in the world’s deadliest offshore oil disaster and led to a major regulatory overhaul.

Total as well as UK authorities have described the expected environmental impact from the plume of gas and a spreading sheen of light oil on the water as “minimal”, although environmental experts said much of the gas “cocktail” would be either flammable or poisonous at close quarters.

Total’s shares have lost about 9 percent in the wake of the incident. They were trading at 37.63 euros at 1305 GMT.

Analysts said the French oil major could face costs of up to $10 billion if its North Sea gas leak leads to an explosion and nearly $3 billion if it takes months to fix.

However, Jefferies securities and investment bank said in a research note that data that had emerged on the spill, which “has further convinced us that the spill consequences should be less than the most pessimistic market estimates and hence that the US$9.7 billion sell-off in the stock since Monday is overdone”.

(Additional reporting by Henning Gloystein and Karolin Schaps in London and Sybille de La Hamaide in Paris; Editing by Jane Baird)

UK: Flare at Elgin Platform Could Ignite Gas Cloud, Experts Say

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The gas leak that occurred at the wellhead platform on the Total-operated Elgin field in the UK North Sea, remains ongoing, the operator reports.

The gas has been flowing since Sunday, March 25th, when Total evacuated all the personnel from the Elgin platform. The precise cause of the gas leak, that has been flowing approximately 240 km east of Aberdeen, is yet to be identified.

According to The Telegraph, experts have warned that the gas cloud which can be seen is very flammable and they described the situation as a disaster waiting to happen because the flare on the Elgin platform is still ongoing.

Total explains that the flare is an integral part of the platform’s safety system, and it is used to safely evacuate all the remaining gas from the platform.  The company says that the flare does not pose a threat, because the winds are taking the gas cloud away from the open flame.

“The wind is forecast to remain in its current direction for the coming days.  You can be assured that this is being reviewed on a constant basis and should this change any impact is being assessed.  In parallel we are investigating solutions to extinguish the flare if it does not burn out by itself.”

Elgin and Franklin are two high pressure/high temperature gas and condensate fields in the Central Graben Area of North Sea. Total E&P UK Limited owns 46.17% and is operator of both fields through its wholly-owned subsidiary EFOG and its average share of production was around 60,000 barrels of oil equivalent per day in 2011.

Elgin/Franklin facilities comprise two wellhead platforms, one on Elgin and one on Franklin and a Production/Utilities/Quarters (PUQ) platform. The PUQ is on the Elgin field and is linked to the Elgin wellhead platform by a 90-metre bridge.

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