This paper will discuss aspects of pipeline integrity, and a perspective of threats and the damage mechanisms of pipelines, namely the presence of defects and the susceptibility (threat) for such defects to initiate and occur, through their related mechanisms.
We start with the broad premise that damage mechanisms become accelerated with the presence of hydrogen in natural gas pipelines, while acknowledging that ongoing research is very active to refine and qualify specific parameters and situations.
Also, as a premise of treating this situation of a pipeline conversion as a change of service, with some common direct steps to establish a readiness for service. A key premise is the nature of establishing a baseline reference for defects and integrity and failure/leakage sources. Including some conventional defects that may become more prominent for integrity concerns due to their potential nature to concentrate H2. (Historically, a significant change would be a liquid to gas operation or vice versa – or a notable change in product like sour gas versus conventional gas).
And fundamentally from a conventional integrity perspective, we will describe aspects of what is the same and what is different for integrity data coming from ILI tools and achieving a state of readiness. This includes a perspective of what readiness means for ILI tools, their operation in hydrogen blended pipelines, and expectations for data reporting.