Novel self-installing anchor for offshore applications

Problem statement

With the growth of oil and gas industry into deep water, the offshore infrastructures have developed to resist deep water conditions up to 3000m. The nature of deep-water environment requires foundations of these systems to sustain a high vertical load while maintaining a reasonable installation cost. However, as the loads sustained by the foundations increase with increasing water depth, the installation becomes more complex and costly. Due to the cost of foundations being a significant percentage of the total cost for an offshore structure, a more reliable and economical foundation type can bring in considerable benefits, especially for deep water applications.

Technology description

Dr. Robert Gilbert, a professor at The University of Texas at Austin, and his students have developed Flying Wing Anchor® (FWA®) as a sustainable anchor concept for deep-water offshore wind turbines. This new concept combines the advantages of low-cost installation of torpedo piles and high efficiency of vertically loaded plate anchors. Anchor is installed mainly in two main steps: initial penetration through free-fall like a torpedo anchor, followed by drag embedment installation like a plate anchor. FWA® is designed to be installed by gravity first with the closed shank which is held on the anchor fluke by the coupling mechanism.

FWA® contains two plates connected by two beams as shown below. The back plate consists of four triangular fins attached on the beams with two oval fins on either side. A fluke-shank coupling mechanism is designed to keep the shank closed and attached to the fluke until the anchor reached the designed pitch angle. FWA® initially dives deeper like torpedo piles and follows drag-embedment installation like plate anchors by using environmental loads, achieving an efficient installation method.