A summary is given for the design and construction of the South Arne-Nybro 24-in. gas pipeline. The main design requirements for the subsea installations are presented: subsea Wye piece configuration to enable gas export from both South Arne and Harald, use of subsea safety valves close to platforms, platform-based control systems for opening of subsea check valves, subsea ball valves and small bore ports for precommissioning, pipeline isolation and contingency purpose, strong protection structures to avoid damage by fishing gear, and, finally, design to avoid scour problems. The design work to achieve these objectives as well as simple installation methods for the subsea assemblies by use of a medium-sized diving support vessel is described. An outline for the offshore construction work is finally given.

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