Composite Repair of Large-Size Diameter Pipe With Severe Metal Loss Defects

Abstract A full-scale testing program was conducted to evaluate the use of carbon-epoxy composite repair technology to reinforce severe corrosion defects in large-diameter pipes. The technical elements associated with this program included reinforcing up to 85% deep corrosion defects in 24-inch diameter pipe samples, including integrating design equations, testing conditions, and performance subject to cyclic pressure and burst testing at elevated temperatures. An objective of the test program was to evaluate changes in the composite design thickness considering a range of severe corrosion depths based on guidance provided in ASME PCC-2, as well as the pressure capacity reductions based on the methodology embodied in ASME B31G. The testing program also evaluated the ASME PCC-2 design guidance subjected to cyclic pressure conditions at 60°C (140°F). The composite technology evaluated in this program has the potential to advance the effectiveness of composite repair while also addressing common severe corrosion defects to guarantee the operational life of a pipeline based on an optimized design configuration. This integration of knowledge based on results obtained in this program holds significant promise in guiding future composite repair procedures, structural reinforcement designs, and material choices, culminating in enhanced structural robustness and dependability of high-pressure transmission pipeline systems.