Gimbal Joint Riser: Enabling Free-Hanging and Buoyancy-Free Rigid Risers

The novel ‘Gimbal Joint Riser’ (GJR) device is an invention that allows for a free-hanging riser catenary configuration by providing the functionality of adding a ‘hinge’ or articulation in midway of the riser column. Such mid-length articulation allows that dynamic bending and compression at touchdown zone (TDZ) be reduced enough to get within acceptable design limits, what is not achievable with a traditional steel catenary riser (SCR) connected to a spread-moored FPSO in ultra-deep-water scenarios like Santos Basin in Brazil. The aim of the invention is to offer an economic competitive option to current state-of-the-art solution of applying Steel Lazy Wave Risers (SLWR), by eliminating the need of relatively expensive buoyancy modules. The objective of this paper is to present this new concept and simulations results.