Toward a non-destructive diagnostic analysis tool of exercises pipelines: models and experiences

Strategic networks of hydrocarbon pipelines, in long time service, are adversely affected by the action of aggressive chemicals transported with the fluids and dissolved in the environment. Material degradation phenomena are amplified in the presence of hydrogen and water, elements that increase the material brittleness and reduce the safety margins. The risk of failure during operation of these infrastructures can be reduced, if not prevented, by the continuous monitoring of the integrity of the pipe surfaces and by the tracking of the relevant bulk properties. A fast and potentially non-destructive diagnostic tool of material degradation, which may be exploited in this context, is based on the instrumented indentation tests that can be performed on metals at different scales. Preliminary validation studies of the significance of this methodology for the assessment of pipeline integrity have been carried out with the aid of interpretation models of the experiments. The main results of this ongoing activity are illustrated in this contribution.