Trelleborg will provide 25 polyurethane-vertebrae Bending Restrictors (Fig. 5) for the static flowlines on the field development and production expansion of the Parque das Baleias oil field, offshore Brazil. Installation and maintenance of the polyurethane-restrictor assembly are less time-consuming and more cost-effective because plastic does not corrode or have to be protected with plating, paint, and anodes. It also has a greatly reduced weight compared with steel, making it neutrally buoyant in water and applying considerably less stress to the flowline and adjacent parts of the subsea structure during both installation and service. These restrictors are often installed to prevent pipes from overbending at the interface between flexible and rigid structures. These bend restrictors have several interlocking elements that react when subjected to an external load, locking together to form a smooth curved radius. This radius is chosen to be equal to or greater than the minimum bend radius of the pipe to which it is applied. Once the elements have locked together, the bending moment is transferred into the elements and back through a specially designed steel interface structure into the adjacent rigid connection, thereby protecting the pipe from potentially damaging loads.
- For additional information, visit www.trelleborg.com/offshore.