The First off-line inspection of a distribution high-pressure gas pipeline in the Czech Republic
April 2016 saw a unique off-line in-line inspection of a DN 300 high-pressure distribution gas pipeline that supplies Brno and, primarily, the Červeny mlyn combined cycle CHP plant. The inspection was carried out on a gas pipeline that had not been built as a cleanable, and therefore piggable, pipeline.
Compared with the standard method where the inspection tools are carried by the flow of the transported utility, here the inspection tool was driven by substitute utility, water.
The key objective of the in-line inspection was specifying very accurately the geometrical parameters along the entire length of the pipeline and identifying any metal loss in pipe walls due to corrosion.
The project employed special technologies that are not normally used in the Czech Republic, or that were applied for the first time ever. They included the off-line inspection, the process of the chemical cleaning of the pipeline and the use of a nitrogen-based inertisation mixture for gas expulsion from the pipeline.
Read more in the article The First off-line inspection of a distribution high-pressure gas pipeline in the Czech Republic (PDF, Czech language, 452 kB).