In order to avoid that the loads generated by the floatingrnunits movements be transferred through flexible risersrnto subsea equipment, significantly additional flow linesrnlength have been used to absorb those loads by line/soilrnfriction. Due to the high costs of these lines, Petrobrasrnhas developed a new anchor system concept to fix thernrisers on the seabed, in lieu of increasing flow linesrnlength. This anchor system, called “Torpedo”, consists ofrna pipe pile filled with scrap chain and concrete, closernended with a cone tip, installed by free fall from arnvessel, and connected to the risers with a special systemrnoperated by ROV. Bundle of three risers have beenrnanchored by each pile with holding power of 1400 kN.rnTaking advantage of the experience in this pile designrnand installation to anchor risers, larger free fall piles withrnholding power up to 7000 kN have been designed andrnalready certified to anchor floating units.rnThis paper aims to present an overview of the designrnand installation procedures, cost estimation, field andrnmodel tests results and applications of the TopedornAnchor System.
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