Grant: Alliance Grants

Pipeline systems are used for the transportation of energy over distance. Transported products include oil, natural gas, synthetic fuels, biofuels, hydrogen, ammonia and byproducts of energy conversion, most notably carbon dioxide. Once a defect has been identified as part of an integrity management program, options exist for repairing the carrier pipe. These range from replacing the defective pipe section, removal of mass at the feature by grinding, weld deposition over the feature, installation of non-pressure (Type A), pressure (Type B), or composite sleeves, mechanical bolt-on clamps, and hot tapping. Type-A sleeves, as investigated in this proposal, are used for non-leaking defects and provide structural reinforcement to a weakened pipeline without requiring welding to the carrier pipe. Repair procedures involving the use of compression sleeves have advantage in that they do not require purging of pipeline segments and are able to be performed without an interruption to customer service. This research investigation will examine the thermo-mechanical processes that occur during application of pipeline compression sleeves to scenarios where it is not possible to reduce operating pressure during installation. Finite Element Analysis will be used to model the application of compression sleeves to carrier pipes. The thermo-mechanical processes that occur during application of compression sleeves will be investigated experimentally and the results used to validate the Finite Element model. Artificial Intelligence/Machine Learning (AI/ML) algorithms will be trained to evaluate the relative merit of different compression sleeve application procedures for varying scenarios. The AI/ML model be used to predict the ratio of hoop stress in the carrier pipe after installation of the compression sleeve to the initial hoop stress in the carrier pipe prior to compression sleeve installation. The result of the AI/ML model will enable determination of carrier pipe stress reduction for a given application procedure, and this will result in improved pipeline safety to both the public and the environment.