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This paper describes the experience of Petrobras in the design, installation and operation of deepwater mooring systems incorporating high efficiency polyester fiber ropes. These ropes have been used now for more than 12 years in catenary and taut configurations to moor drilling and production units as well as storage and offloading facilities. The paper provides a history of the development of this technology, highlighting the key issues involved in introducing in mooring systems a component that has non-linear visco-elastic behavior. Differences to all steel systems in terms of: behavior, failure modes and design criteria and procedures are discussed. The paper presents the life cycle management strategy adopted by Petrobras in the early years of the use of this technology and its evolution that have guaranteed that the only failure mode observed over all these years was mechanical damage. It is expected that this paper shows that the use of polyester (polyethylene terephthalate) ropes in deepwater moorings is a mature technology.

The production approach adopted for Campos Basin oil fields has been strongly based on subsea completed satellite wells, floating production units and oil offloading through oceanic terminals. Flexible flowlines, risers and umbilicals have played an important role in this scenario, gradually building an outstanding reputation of reliability and cost-effectiveness. With a background of more than 3,500km of flexible lines and umbilicals already deployed in water depths ranging from 100m up to 1853m (present world record), it is natural that the "flexible solution" has been adopted for almost the totality of Marlim giant field applications. This paper encompasses the technical evolution of flexible flowlines, risers and umbilicals, highlighting some milestones as world records and pioneer applications, installation and pull-in procedures, keeping the main focus over projects in Marlim field. The adoption of new products like protection against coral, IPU (Integrated Pipe and Umbilical), collapse resistant hoses for chemical injection, etc., is also presented. The paper reports the installation of a 10-inch gas export steel catenary riser (SCR) on platform PETROBRAS-18, as the first of its kind on a semi-submersible unit in the world. New trends under evaluation like the use of tension leg riser system and long length deepwater bundles installed through controlled depth tow method (CDTM), both considered as competitive solutions compared to flexible lines, have their scenarios presented and discussed in the paper. The paper also emphasizes the partnership between PETROBRAS and suppliers, contractors, universities and operators around the world, that made it possible to overcome challenges faced to bring Marlim field production onstream. Problems that occurred on the course of operations are also discussed.

This paper describes the experience of Petrobras in the design, installation and operation of deepwater mooring systems incorporating high efficiency polyester fiber ropes. These ropes have been used now for more than 12 years in catenary and taut configurations to moor drilling and production units as well as storage and offloading facilities. The paper provides a history of the development of this technology, highlighting the key issues involved in introducing in mooring systems a component that has non-linear visco-elastic behavior. Differences to all steel systems in terms of: behavior, failure modes and design criteria and procedures are discussed. The paper presents the life cycle management strategy adopted by Petrobras in the early years of the use of this technology and its evolution that have guaranteed that the only failure mode observed over all these years was mechanical damage. It is expected that this paper shows that the use of polyester (polyethylene terephthalate) ropes in deepwater moorings is a mature technology.