Bundles and towed installation

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Bundles and towed installation

Initial studies have demonstrated that this is a viable alternative to conventional riser installation techniques.

BUNDLECONNECTIONATFIELD

BUNDLE CONNECTION AT FIELD

ƒ Simple method – normal insulation needs ƒ Flexible jumpers or rigid spools

50 m

(150 ft)

ƒ Direct connection – high thermal insulation ƒ Pre-installed flanged spools – no metrology ƒ Docking probes

It is possible to connect two or more bundles in the field, each up to 7.5 km (5 miles) long, enabling longer step-outs to be constructed. The simpler connection method is to lay down the tow and trail heads side-by-side at the ends, so that they can be connected with flexible jumpers or rigid spoolpieces. Sometimes, however, the risk of thermal losses means that only short spools can be used. In this case, the tow and trail heads are docked into each other, already fitted with the short, well-insulated pipe stub ends. Rigid flanged connections are then made up between the flowline ends by divers. There is no need for underwater metrology.

TOWHEADSTRUCTURESSUMMARY