Deepwater lowering has seen a rapid development over the past 20 years. From the first foundation piles of Tension Leg Platforms in 1000m water depth, via the installation of heavy anchor piles in 2000 to 3000m of water, the industry is now at the brink of lowering heavy and sizable subsea production units into deep and ultra-deep water. When investing in Deep Water Lowering equipment, the discussion circles around the choice for steel wires or fiber ropes. These two cannot easily be exchanged with the aim to test the new technology of fiber ropes or to simply use the best of both in the given situation. As steel wires and fiber ropes require totally different systems that mutually exclude each other, the choice has the nature of an either-or decision. This either-or decision is further complicated by the fact that the dynamic behavior of Deep Water Lowering systems strongly depends on the vessel from which it is operated; on the water depths in which it is deployed; and on the wave climate in which the operation takes place. Moreover, small and slender structures behave totally differently as compared to large and heavy ones when lowered to the seabed.
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