Qualification of Composite Armor Materials for Unbonded Flexible Pipe

摘要

This paper presents the plan and execution of a comprehensive test program to qualify composite tensile and pressure armor materials for application in unbonded flexible pipe for deep and ultradeep water, high temperature and pressure production and high pressure injection service. Due to lighter weight and resistance to corrosion and fatigue, composite materials are being implemented for the pressure and tensile armor in unbonded flexible pipe. A material qualification program is necessary to define material properties that are used in design and to assure that the materials will meet performance requirements over the service life. The material qualification testing program presented in this paper can also be used as a model for other composite material qualification programs for offshore applications.rnThe qualification test program was developed based on the design of the pressure and tensile armor layers, and a comprehensive evaluation of the potential failure modes and associated failure mechanisms associated with the application of composite armor materials for the layers. The material qualification program was developed based on the guidelines presented in DNV-OS-C501 Offshore Standard for Composite Components. Since composite materials are anisotropic, material properties in the principal directions needed for analysis, and how these properties vary with time as a result of the loads and environments experienced over the service life are evaluated. The material qualification requirements have been agreed by members of the flexible pipe technical community and are being published in Draft International Standard API 17J/ISO 13628-11 as Annex H. This paper summarizes the requirements and presents one manufacturer's initial work to qualify both fiberglass and carbon fiber based composite armor materials for the pressure and tensile armor layers in unbonded flexible pipe.