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Transcripción del abstract original del autor: This paper is a true story how gas transmission company decided after pipeline risk assessement work to inspect an old high pressure gas transmission pipeline The original design of the pipeline that goes through high populated areas was non-pigable. Modification of the pipeline; new valve stations with pig traps were designed and installed. Next step was the cleaning and calibration of the old dirty pipeline. A lot of dust and debris was pushed out from the pipeline. And finally the inspection pig run, how the inspection tool goes in tight bends and over river grossing within bridge. Results from inspection run. Serious defects were found just at last moment before failure. Main reason for defect was bad design combined with small coating failure and AC-currents from nearby bridge with electrical power cables. The gas pipeline goes in the same bridge over river. Also very interesting is that within that certain pipe spool defect was located, there were no cathodic protection. During construction some money was saved so that insulating joints were installed underground instead above ground installation, so the spool next to bridge was left without CP. It was also one reason for defect. To continue safe gas transmission, more traps will be installed to existing pipelines, and they will be inspected. All new pipelines will be built pigable and baseline surveys will be made to get fingerprints after construction.