If you’ve ever performed an Inline Inspection (ILI) for a pipeline, you are likely familiar with the typical product of the survey which takes the form of a spreadsheet. This spreadsheet is usually referred to as a pipeline listing, master list, pipe tally, or similar and is a tabular dataset where each row is a feature reported by the ILI vendor. As seen in the example below, numerous columns are populated with data describing each feature such as: distance from launch, feature description, dimensions, and much more depending on the operator’s reporting specifications.
There is quite a lot of work that leads up to the generation of the listing including prepping the line, running the ILI tool, processing the data, analyzing the data, and generating the report. Inline inspections can cost anywhere from thousands to hundreds of thousands of dollars (or more!), the results of which ultimately culminate into one final deliverable: the pipe listing. I sometimes joke that an operator can say “I spent tons of money on an ILI run and all I got was this spreadsheet.” Rather than review the entire process, for now I want to focus just on that (expensive) pipe listing.
Each row of a pipe listing contains a reported feature or anomaly, but where does that information come from? Is it accurate? Can I trust it? So many decisions are made based on the information reported in the pipe listing so I think it warrants a closer look at its building blocks.