| Once limited almost exclusively to aerospace applications, the use of composite materials has become widespread among many high performance industries. Today's petroleum industry is requiring piping systems to sustain high pressures, impact, rugged handling, and harsh environmental conditions such as corrosion and temperature. Advances in the last decade of engineered materials have opened the way for more conversions from metal to composites.;The objective of this research is to develop a lightweight composite pipe that meets the performance requirements of an existing high-pressure steel pipe. This development is crucial to the petroleum industry where hydraulic-fracturing services are demanding lighter weight materials while maintaining low cost and high reliability. A hybrid steel/composite pipe was designed and analyzed using the finite element analysis (FEA) programs SDRCRTM I-DEASRTM and ABAQUSRTM. The design consisted of a thin-walled steel liner with a composite over-wrap. It employed the use of unique end fittings, which transfer longitudinal and torque loads from the steel to the composite. This research is believed to be the first instance where autofrettage is used on a metal lined composite pipe. Results from FEA were used to validate the design and fabricate a full-scale prototype. The prototype was successfully tested and exceeded maximum design pressure. |
