Posted on 04.10.2011 - 12:00 EDT in GENERAL NEWS by Rons_ROV_Links
Tideway, the Dutch offshore expert for the oil and gas industry, starts today with implementing an erosion protection system at the Prirazlomnoya rig in the north of Russia. In total, a stone fill of 100,000 tonnes over a period of more than forty days is involved. The commissioning authority is the Russian energy giant Gazprom Neftshelf. The activities are carried out to the south-west of Nova Zembla, in the Barents Sea. Tideway works in extreme circumstances at this location. The stones are loaded in Murmansk. The overall contract value of the project amounts to 50 million Euro.
The offshore industry consists of, among other things, laying infrastructure at sea for the export of oil and gas and protecting oil and gas pipelines at sea. Tideway boasts a worldwide reputation as an innovator in the field of stabilisation and protection of pipelines and high-voltage cables. Laying and protecting deep sea pipelines is crucial to the exploitation of new energy sources. Against the background of the increasing shortage of energy in the world, the importance of this discipline has increased considerably over the past years.
The Prirazlomnoya Project will be executed in the Arctic area below Nova Zembla in the coming months. The project entails the stone fill of approximately 100,000 tonnes of quarry stone to protect a new offshore rig against erosion. The rig has been built by J.S.C. Sevmash for the account of Gazprom Neftshelf and is towed from Severodvinsk to the Prirazlomnoya oil field near Varandey in the Kara Sea, south-west of Nova Zembla. There, it will be permanently installed on the sea bed and provided with the necessary protection by Tideway.
Seahorse loading rock at quarry.The Prirazlomnoya oil rig in the Barents Sea has to be able to withstand extremely low temperatures and the considerable formation of ice. The location is only free from ice 110 days per year, the average annual temperature amounts to -4 degrees Celsius whereby the temperature may drop to -50 degrees Celsius in the winter.
One can only work in the area four months a year. The severe climate and the restrictions imposed by the considerable formation of ice, impose the highest requirements on the technology to be used. The Prirazlomnoya rig has been built especially for the exploitation of the oil field and is the first oil production project in the Russian Arctic Sea region. The oil field was discovered in 1989 and is situated 60 km off the coast on the continental terrace in the Pechora Sea. The Prirazlomnoya ice-resistant fixed oil rig is crucial to the exploitation of the oil field. The production capacity amounts to 18,000 tonnes of crude oil a day.
The bulk of the work is done using the Tideway fall pipe vessel Seahorse. The fall pipe vessel Seahorse is especially withdrawn from the Barents Sea where it has been carrying out protection activities on the Nordstream gas pipeline project, also for Gazprom. The DP2 fall pipe vessel Seahorse can take 17,000 tonnes of quarry stone on board and place it with great precision up to depths of 1,000 m thanks to special equipment.
The sorted quarry stone is stored in the hold of the Seahorse. The 'fall pipe' that is suspended underneath the vessel, ensures that the quarry stone ends up on the exact spot above pipelines or directly on the sea bed. The bottom end of the pipe is equipped with a Remote Operated Vehicle (ROV). This ROV is operated from the deck and controls the laying of the quarry stone in three dimensions and allows for precision work.