Composite production riser - Testing and qualification

The production riser is a tension leg platform (TLP) component that lends itself to taking advantage of the unique properties of advanced composite materials. A composite production riser (CPR) has the potential to reduce capital expenditure and improve reliability for development of reservoirs in deep water because of its lighter weight, improved corrosion resistance, and excellent fatigue performance compared with steel risers. In 1995, a project was organized by several oil, service, and composite manufacturing companies and partially sponsored by the U.S. Dept. of Commerce Natl. Inst. of Standards and Technology Advanced Technology Program to develop a cost effective CPR for deepwater applications and to overcome the technical challenges in design, analysis, fabrication, and qualification of a CPR. A critical element of this project is the specification and implementation of a comprehensive testing program to confirm the advantages, validate the design, and establish the long-term performance of a CPR as well as to secure the confidence of both operational staff and certifying authorities. The testing program was designed to identify performance limitations, establish the failure envelope for the full-diameter CPR joints, and verify that the manufactured CPR meets the performance requirements for application on a TLP in the Gulf of Mexico. In addition, the testing program, combined with the analytical effort, was planned to establish statistical variations in strength factors and to generate data to design CPR's of different sizes and for different operating conditions. This will allow for site-specific qualification of a CPR with minimal testing. In this paper, we discuss the testing program, review its rationale, and present currently available results. Test results clearly illustrate that current state-of-practice for design and manufacturing of composite CPR joints are well advanced to achieve the required cost effectiveness and high reliability for use in deepwater developments.