It is extremely important that a pipeline be in clean condition prior to an In-Line Inspection (ILI) run. Loose or adhered deposits and scale can cause a range of issues from sensor “lift off” that causes the tool sensors to be ineffective and unreliable to a pipeline becoming plugged with deposits in front of the inspection tool. These issues can require costly repeat runs of the inspection tool or, in the worst case, the tool can become stuck in the pipeline and need to be cut out to remove it.
Here we see an In-Line Inspection tool completely packed with wax deposits. This line had been pigged with existing maintenance pigs that were on-site and available to the operations team. The pigs being used were in poor condition.
Chemical assistance was necessary in this project. We highly recommend that your chemical vendor be involved in program planning when solids are present.
shows a badly worn pig that was used to pig this line prior to ILI. The operators felt that the line
was clean as they were seeing no returns on the pig when receiving it. In reality the pig was worn beyond its useful life and was not providing adequate cleaning.
Here we see the received condition of a properly sized aggressive cleaning pig after one run.
Now, this photo shows the received condition of this pig after the final cleaning stage at the end of the cleaning program that we designed for this specific line.
With proper line preparation prior to running an Inspection tool we can avoid costly tool recovery and tool re-run expenses. The key is to understand the type of debris we may encounter when designing an effective cleaning program.
Our client had been installing new pipelines and had issues with In-Line Inspection tools becoming clogged with ferrous debris that caused skewed sensor data and sensor “lift off”. These were base line inspection runs performed after hydro test. The fluids used in hydro test tend to be recovered and reused over and over and can be quite dirty. There is also a lot of ferrous material left behind in the construction process ranging from grinder filings to hardware.
This photo shows the results of magnetic pig runs, post hydro test, prior to ILI and the
amount of debris that is possible in what should be a clean new pipeline. It also speaks to the inefficiency of foam pigs that are widely used as cleaning pigs in the construction of pipelines.
This photo shows the results of magnetic pig runs, post hydro test, prior to ILI and the
amount of debris that is possible in what should be a clean new pipeline. It also speaks to the inefficiency of foam pigs that are widely used as cleaning pigs in the construction of pipelines.
This photo shows the results of an effective cleaning program prior to ILI.
This is the received condition of an ILI tool used in our client's project. Aside from some dirty hydro test fluids the tool is in clean condition with near zero pipeline debris on the tool.
This is an on-going project and to date our client has not had to re-run any of the inspection tools in the lines they have built.
