An oil platform is a large structure with facilities to extract and process petroleum and natural gas that lie in rock formations beneath the seabed. Many oil platforms will also have facilities to accommodate the workers, although it is also common to have a separate accommodation platform linked by bridge to the production platform. Most commonly, oil platforms engage in activities on the continental shelf, though they can also be used in lakes, inshore waters, and inland seas. Depending on the circumstances, the platform may be fixed to the ocean floor, consist of an artificial island, or float. In some arrangements the main facility may have storage facilities for the processed oil. Remote subsea wells may also be connected to a platform by flow lines and by umbilical connections. These sub-sea facilities may include one or more subsea wells or manifold centres for multiple wells.
Offshore construction is the installation of structures and facilities in a marine environment, usually for the production and transmission of electricity, oil, gas and other resources. It is also called maritime engineering.
The Saipem 7000 is the world's third largest semi-submersible crane vessel, after the SSCV Sleipnir and the SSCV Thialf. It is owned by the oil and gas industry contractor Saipem S.p.A.
A drillship is a merchant vessel designed for use in exploratory offshore drilling of new oil and gas wells or for scientific drilling purposes. In recent years the vessels have been used in deepwater and ultra-deepwater applications, equipped with the latest and most advanced dynamic positioning systems.
Marine architecture is the design of architectural and engineering structures which support coastal design, near-shore and off-shore or deep-water planning for many projects such as shipyards, ship transport, coastal management or other marine and/or hydroscape activities. These structures include harbors, lighthouses, marinas, oil platforms, offshore drillings, accommodation platforms and offshore wind farms, floating engineering structures and building architectures or civil seascape developments. Floating structures in deep water may use suction caisson for anchoring.
Offshore drilling is a mechanical process where a wellbore is drilled below the seabed. It is typically carried out in order to explore for and subsequently extract petroleum that lies in rock formations beneath the seabed. Most commonly, the term is used to describe drilling activities on the continental shelf, though the term can also be applied to drilling in lakes, inshore waters and inland seas.
Subsea technology involves fully submerged ocean equipment, operations, or applications, especially when some distance offshore, in deep ocean waters, or on the seabed. The term subsea is frequently used in connection with oceanography, marine or ocean engineering, ocean exploration, remotely operated vehicle (ROVs) autonomous underwater vehicles (AUVs), submarine communications or power cables, seafloor mineral mining, oil and gas, and offshore wind power.
"Offshore", when used in relation to hydrocarbons, refers to operations undertaken at, or under the, sea in association with an oil, natural gas or condensate field that is under the seabed, or to activities carried out in relation to such a field. Offshore is part of the upstream sector of the oil and gas industry.
Pioneering Spirit is a catamaran crane vessel owned by the Switzerland-based Allseas Group designed for the single-lift installation and removal of large oil and gas platforms and the installation of record-weight pipelines. The 382-metre-long (1,253 ft), 124-metre-wide (407 ft) vessel is the world's largest vessel by gross tonnage, the heaviest vehicle ever made and since September 2021 also the largest floating sheerleg in the world. It was built in South Korea by Daewoo Shipbuilding & Marine Engineering in 2013 at a cost of €2.6 billion. It commenced offshore operations in August 2016.
Offshore concrete structures, or concrete offshore structures, are structures built from reinforced concrete for use in the offshore marine environment. They serve the same purpose as their steel counterparts in oil and gas production and storage. The first concrete oil platform was installed in the North Sea in the Ekofisk oil field in 1973 by Phillips Petroleum, and they have become a significant part of the marine construction industry. Since then at least 47 major concrete offshore structures have been built.
Allseas Group S.A. is a Dutch offshore contractor specialising in pipelay, heavy lift and subsea construction. It was founded in 1985 by owner and president Edward Heerema, employs 4,000 people and operates worldwide.
Solitaire is a large deep-sea pipe laying ship. It was at the time of conversion the world's largest pipe-laying ship at 300 metres (984 ft) long and 96,000 tonnes. When fully operational she has a crew of 420, a pipe carrying capacity of 22,000 tonnes and a pipe lay speed of more than 9 kilometres (5.6 mi) a day. The ship is owned by the Allseas Group, a Dutch pipelaying and marine construction firm with their headquarters in Switzerland.
The Castoro Sei was a column stabilized semi-submersible pipelay vessel. She had an overall length of 152 metres (499 ft), a width of 70.5 metres (231 ft) and an operating draught of 7.8 to 15.5 metres.
Commercial offshore diving, sometimes shortened to just offshore diving, generally refers to the branch of commercial diving, with divers working in support of the exploration and production sector of the oil and gas industry in places such as the Gulf of Mexico in the United States, the North Sea in the United Kingdom and Norway, and along the coast of Brazil. The work in this area of the industry includes maintenance of oil platforms and the building of underwater structures. In this context "offshore" implies that the diving work is done outside of national boundaries. Technically it also refers to any diving done in the international offshore waters outside of the territorial waters of a state, where national legislation does not apply. Most commercial offshore diving is in the Exclusive Economic Zone of a state, and much of it is outside the territorial waters. Offshore diving beyond the EEZ does also occur, and is often for scientific purposes.
A submarine pipeline is a pipeline that is laid on the seabed or below it inside a trench. In some cases, the pipeline is mostly on-land but in places it crosses water expanses, such as small seas, straits and rivers. Submarine pipelines are used primarily to carry oil or gas, but transportation of water is also important. A distinction is sometimes made between a flowline and a pipeline. The former is an intrafield pipeline, in the sense that it is used to connect subsea wellheads, manifolds and the platform within a particular development field. The latter, sometimes referred to as an export pipeline, is used to bring the resource to shore. Sizeable pipeline construction projects need to take into account many factors, such as the offshore ecology, geohazards and environmental loading – they are often undertaken by multidisciplinary, international teams.
A pipelayer is a skilled tradesman who lays pipe, such as for storm sewers, sanitary sewers, drains, and water mains. Pipelayers may grade trenches and culverts, position pipe, or seal joints. The Standard Occupational Classification System code for pipelayers is 47-2151.
HYSY 202 is a non self propelled, shallow water pipe laying barge, owned by CNOOC, the national oil exploration company of China. Built in 2012, it is one of the six large crane barges owned by COOEC and CNOOC, namely "HYSY201", "HYSY 202", "Lanjing", "Blue Xinjiang", "Binhai 109", "HYSY286", "HYSY289" and "HYSY291".
Lanjing (蓝鲸) is a self-propelled, deep water crane vessel, owned by China National Offshore Oil Corporation (CNOOC), the national oil exploration company of China, through its Hong Kong-listed subsidiary CNOOC Limited. Built in 2012, it is one of the six large crane barges owned by COOEC and CNOOC, namely HYSY201, HYSY 202, Lanjing, Blue Xinjiang, Binhai 109, HYSY286, HYSY289 and HYSY291.
Ocean development refers to the establishing of human activities at sea and use of the ocean, as well as its governance.
Marine construction is the process of building structures in or adjacent to large bodies of water, usually the sea. These structures can be built for a variety of purposes, including transportation, energy production, and recreation. Marine construction can involve the use of a variety of building materials, predominantly steel and concrete. Some examples of marine structures include ships, offshore platforms, moorings, pipelines, cables, wharves, bridges, tunnels, breakwaters and docks. Marine construction may require diving work, but professional diving is expensive and dangerous, and may involve relatively high risk, and the types of tools and equipment that can both function underwater and be safely used by divers are limited. Remotely operated underwater vehicles (ROVs) and other types of submersible equipment are a lower risk alternative, but they are also expensive and limited in applications, so when reasonably practicable, most underwater construction involves either removing the water from the building site by dewatering behind a cofferdam or inside a caisson, or prefabrication of structural units off-site with mainly assembly and installation done on-site.
