A Disconnectable Fluid Transfer System for Dynamically Position Ship Shaped provide great means for managing risk as it relates to avoiding harsh environmental events and protecting the subsea facilities in the event of a drive off. A set of alarm systems on the vessel, provide disconnect criteria due to weather conditions, fire, process emergency shut down and vessel offset from nominal position. A buoy, connected to the vessel, detaches to allow the vessel to either relocate or resolve the issue triggering the disconnect. The buoy sinks to a preset level via an attached clump weight. This operation has profound implications for the riser and umbilical system design as it must be designed for two operating modes, connected and disconnected, along with the transient dynamic cases going from one to the other under both planned and emergency scenarios. The paper presents the challenges faced during the Phoenix field riser and umbilical analysis to define the operational envelope for these components, including the development of the load case matrix from the huge parameter space to satisfy regulatory requirements, and the operational importance of the connection and disconnection procedures. Additionally the paper addresses the implemented passive monitoring system developed as part of the integrity assurance for the disconnectable system.
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