Forties oil line replacement overcomes sandwave challenge

Journal Article · Wed Mar 06 04:00:00 EST 1991 · Oil and Gas Journal; (United States)

OSTI ID:5979568

Steel, W J.M.; Imglis, R ^[1]

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1. BP Exploration, London (GB)

A major new 36-in., oil-export pipeline has been installed in the North Sea between the Forties field and Cruden Bay on the U.K. mainland. Designing and installing the line involved solving problems caused by sandwaves in the nearshore segment of the route. The Forties pipeline system covers offshore and land pipelines between the Forties field and the Firth of Forth tanker loading terminal and incorporates oil transportation, stabilization-gas separation, processing, and storage. The pipeline is used as part of an integrated oil and gas liquid gathering system from the central North Sea. Oil and gas liquids from other offshore fields are connected by subsea pipelines and riser to the Forties Charlie platform. Inspection of the existing 32-in. offshore pipeline had indicated signs of corrosion which would prevent the system from operating economically as future demands increased. In addition, when the line was commissioned in 1975, it was not envisioned that it would eventually carry crude from several other fields, which will come onstream this decade. The decision to lay a new 36-in. sealine reflects this need for increased capacity to ensure that the Forties pipeline system continues as a major carrier of oil and gas liquids well into the next century. Corrosion monitoring and inspection of the 32-in. line led to sections of the topside pipework being replaced in 1985 and the top section of the rise in 1987. The corrosion also resulted in the pipeline maximum allowable operating pressure (MAOP) being limited to 115 barg (1,668 psig) from 129 barg (1,871 psig).

• OSTI ID: 5979568
• Journal Information: Oil and Gas Journal; (United States), Journal Name: Oil and Gas Journal; (United States) Vol. 89:18; ISSN OIGJA; ISSN 0030-1388
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
022000* -- Petroleum-- Transport
Handling
& Storage
ATLANTIC OCEAN
CHEMICAL REACTIONS
CORROSION
DESIGN
DEVELOPED COUNTRIES
ENERGY SOURCES
EUROPE
FOSSIL FUELS
FUELS
INSTALLATION
NORTH SEA
PETROLEUM
PIPELINES
RETROFITTING
SEAS
SURFACE WATERS
TRANSPORT
UNDERWATER OPERATIONS
UNITED KINGDOM