Code Compliance of a New Metallic Composite Pipeline

Abstract

The composite pipe system, known as XPipe™, is a steel strip laminate technology which uses high-performance adhesives to manufacture a metallic composite pipe. It offers a new method of low cost pipeline construction suitable for onshore gas and oil pipelines in a variety of configurations. The pipe is based on a thin wall liner that provides the fluid containment, the material of which will vary according to service requirements. Fusion bonded epoxy (FBE) coated martensitic ultra-high strength steel strips are then pre-formed and helically wound around the liner to form a laminated high strength reinforcing layer providing the pipe’s hoop strength. These are bonded using an adhesive. Unlike conventional linepipe that is manufactured in a pipe mill away from the construction site, this lightweight composite pipe can be produced at the construction facility using a portable manufacturing line. All components of the manufacturing process fit within standard ISO containers, each weighing between 5 and 15 tonnes. This allows for easy transportation via truck, and handling or shipping. Existing regulations and codes make no specific reference to metal composite pipes. They are mainly written for steel pipe lines with some mention of plastic pipe. The paper presents a comprehensive review of the following US onshore design codes (ASME B31.4/B31.8) and relevant regulations (CFR (DOT) 49 P192 / P195) in order to establish the applicability of these codes for use on XPipe. The paper describes how XPipe meets the code and regulation requirements with regard to safety, design, material, construction, inspection, testing, operation and maintenance. The paper will identify any areas where XPipe does not meet code and regulation requirements and describe the testing and /or design changes that have been made in order to meet the code requirements. The paper will focus on the how the XPipe can meet the practical requirements of these codes. The paper will describe how the qualification testing is being performed in accordance with DNV-RP-A203 Qualification Procedures for New Technology. The qualification testing focuses on how the XPipe meets or exceeds pipeline safety margins with regard to typical failure modes such as yield, burst, facture, fatigue, collapse, etc. This is a continuous process and is being updated after each step using the available knowledge on the status of the qualification.