Flexible risers with composite armor for deep water oil and gas production

This paper discusses the development of a light weight high strength flexible pipe for the conveyance of oil and gas from deep water subsea wells to floating production vessels. Flexible pipe is a multilayer structure of helically wound metallic strips and tapes and extruded thermoplastics. The tensile armor layer in conventional pipe consists of high strength steel rectangular wires wound in opposing directions to provide torque balance. The light weight design incorporates carbon fiber/polymer thermoplastic composite strip to replace the steel armor. A weight reduction of 30% is expected for a pipe designed to meet the same performance requirements. The results of tests conducted to qualify the composite armor material and pipe structure and initial efforts to develop a composite armor layer service life model are presented herein.