Australia has a long tradition of innovation in the use of floating production systems in the past 20 years. The classical solution adopts unbonded flexible pipe, a key technology, to enable floating facilities to produce in relatively shallow waters. While unbonded flexible pipe is a reliable technology that has been in use for approximately 30 years, damage, and ultimately failure can occur during its early (i.e. during manufacturing/testing, installation and early operation) and later life.
Accurate assessments of the historical records of flexible pipe usage have led to an increased understanding of the potential failure mechanisms. This enables mitigation of incidents by developing operating strategies and procedures to manage the flexible pipe in a knowledgeable and cost effective manner.
This paper discusses the available techniques for the inspecting and monitoring requirements of flexible pipe, including consideration of the value offered by conventional general visual inspection (GVI) techniques. Examples of developed alternative technologies are discussed, as well as how these alternatives can reduce the requirement for GVI when supplemented with an integrated integrity management strategy.
Furthermore, given the advances in understanding of complex flexible pipe inter-layer behaviour, this paper demonstrates that through proper asset management, flexible pipe technology service life can be extended beyond the original design value. Similarly, flexible pipe that had previously been considered damaged and requiring early replacement can be justified for extension to beyond the original design life.
Consideration has also been given to the potential for the re-use of flexible pipes and the hazards which can arise from this activity including recovery, storage, testing and installation. The key stages required to safely manage this process have been outlined.