Bundles and towed installation

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Bundles and towed installation

FLAT-PACK BUNDLES

Carrier pipe filled with kerosene (instead of N 2 )

or seawater with macrospheres

Strapped on spacer

Flowlines

Flat-pack bundles with low density filled buoyancy pipe: Kerosene or similar is contained inside a plastic buoyancy pipe and pressure compensated Kerosene can be transported, injected into a buoyancy pipe and recovered after deep- water installation After the initial investment, buoyancy pipe and kerosene can be re-used many times Flat-pack bundles with macrosphere buoyancy: Macrospheres with various depth ratings can be packed into carrier pipe prior to the launch Macrospheres are then recovered by pumping out the water and pigging the carrier pipe Additional buoyancy could be achieved using a combination of the above – that is filling with kerosene and macrospheres. This would require more complicated recovery operations following use. Flat-pack bundles may be economic for shallow water when there are only a few flowlines, avoiding the need for a permanent steel carrier. Carrier pipe can be allowed to ‘free flood’ during tow to field Bundle is positioned on seabed by flooding the flowlines

DEEP-WATERBUNDLESSUMMARY