Bundles and towed installation

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Bundles and towed installation

The 0.6 m high by 1 m wide (2 ft by 3 ft) bundle is to be installed in a 2.7 m (9 ft) deep pre- excavated trench in the seabed, giving almost 2 m (7 ft) of cover when backfilled in order to prevent uplift buckling. Backfill to the trench also protects against ice gouging and strudel scour (where river water flows offshore over the ice each summer, scouring a hole through the floe and whirl-pooling down into the seabed beneath). The pipeline continues onshore for a further 3.7 km (2.3 miles), making the pipeline length a total of 12.7 km (7.9 miles). Source: Offshore Engineer June 2006.

FLOW-LAY

FLOW-LAY

ƒ Flow-lay £ ƒ Developed by Land and Marine as part of a Shell cost-saving initiative ƒ Used successfully for Gullane Outfalls ƒ 610 mm (24 in) by 650 m (2130 ft) – storm water ƒ 273.1 mm (10¾ in) by 1200 m (3940 ft) – main outfall ƒ Offers major cost savings ƒ Small tugs – launch and bollard pull <30 tonnes ƒ Method in shallow water & marshy shores ƒ Contact tim.ley@landandmarine.com The Gullane outfalls were constructed at Kvaerner’s Methill yard, to the east of Edinburgh by Land and Marine Project Engineering Ltd, and floated across the Firth of Forth using 400 mm and 450 mm (16 in and 18 in) standard HDPE pipe as a carrier. Launch tow and installation tension loads were no more than 30 tonnes (33 US tons).

FLOW-LAY