Cracks interacting with dents are among the most critical features to identify and remediate, not only for the potential to cause harm to an asset but also because their identification is part of federal regulation in the United States (PHMSA title 49 CFR 192).
This regulation considers dents with any stress riser as an immediate threat that requires rapid verification and remediation.
Several factors contribute to the rigor applied to Cracks in Dents Diagnosis. The dent by itself causes a stress concentrator, adding to the internal pressure cycling which, in turn, causes the asset to fatigue. Unchecked, the area around this fatigue becomes fertile ground for new crack growth. Making the problem even more complex, the detectability of crack-in-dent features is correlated to their placement within a pipeline and is also contingent on whether the dent is restrained or unrestrained. If cracks, grooves, or gouges interact with these dents, they can pose an immediate threat to pipeline integrity.