Qualification of Thermoplastic Composite Pipe Risers: Combined Pressure and Bending Loading

Abstract

In offshore ultra-deepwater oil fields, weight and cost reduction is one of the operators’ top priorities, while maintaining safety and reliability standards. These challenges have made conventional flexible risers a less favourable choice for new construction and replacement projects and have forced asset owners to explore cost saving through innovative technologies such as Thermoplastic Composite Pipe (TCP). Magma Global’s light weight m-pipe® TCP riser and flowline product offers over 40% reduction in installed riser project costs, while bringing exceptional permeation, corrosion, high-temperature and fatigue performance and most importantly long-term reusability benefits. This product is the subject of a thorough qualification program in agreement with the requirements of operators and independent verification agents (IVA) to demonstrate the product’s safety and reliability to asset owners and local regulatory bodies. This paper presents recent developments on the qualification campaign of m-pipe® TCP for riser applications, with a focus on combined pressure and bending tests designed to verify the pipe strength and stiffness. It addresses the product’s ability to withstand loading in the riser touch-down region of a Free Hanging Catenary (FHC). The qualification process of sample manufacture, rig setup, instrumentation & testing, design model development and validation is presented. Burst load cases and combined bend & burst load cases are tested on m-pipe® and results are compared against design model predictions. We hope the paper will be of interest to anyone working in new material development or product qualification in the offshore industry.