Off-line inspection: An Important tool for investment decisions
A natural gas leakage was detected on the Kasejovice–Mikulášov high-pressure DN 600 pipeline near Čížová after 50 years of operation. The pipeline was uncovered and found to suffer from extensive corrosion; corrosion with similar dimensions was also found when another part of the pipeline was uncovered on the same site.
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Applying good management principles, the operator therefore decided to carry out in-line inspection on a representative 15km section in order to check the actual condition of the piping and, on the basis of the results, determine further procedure for repair or renovation.
Conventional in-line inspection during operation is not feasible on most gas distribution pipelines, and the inspection was therefore carried out ‘off-line’: an ultrasonic inspection pig was pushed through the pipe in a controlled manner using water.
Read more in the article Off-line inspection: An Important tool for investment decisions (PDF, Czech language, 2681 kB).