Traditional inline inspection assessments are widely used across the industry, and although these assessments have been refined over the years, they continue to yield conservative predictions that produce less than optimal results. One of the assessments that is often applied to inline inspections is Finite Element Analysis (FEA), which is optimized to provide operators with an accurate estimation of pressure behaviors.
Unfortunately, the assessment is not always accurate. FEA is considered one of the most complex assessment methodologies available and is included as "Level 3" in standards such as API 579-1.
So, why are these assessments not as accurate as they should be? It's quite simple. Several engineers interpret the data based on assumptions. Naturally, this causes skepticism among the operators who are investing in this service and end up receiving results that could be open to interpretation and inaccuracy.
When an inline inspection (ILI) device or tool is the source of this input, there are multiple variables to consider: sensor types, mechanical configuration, resolution (axial and circumferential sampling), temperature, pressure, speed, rotation, and several more noise inducers. These complex components require a detailed application process that traditional inspections may not incorporate into their analysis processes.