Transneft Diascan has received patent No. 2714868 for the Pitting Corrosion Detection Method invention.
The new method is designed to detect pitting corrosion of a pipeline wall by ultrasonic transducers used in ultrasonic thickness measurement.
Pits (pitting corrosion) are a typical stress concentrator where there is a sharp increase in mechanical stresses that increases the risk of pipeline damage. Identification of such defects, taking into account the small size of pits and the difficulty of their detection by known methods of ultrasonic thickness measurement, is a hard task when carrying out in-line inspection of pipelines.
The method developed by Transneft Diascan is based on the energy criterion for detecting pipeline defects instead of the amplitude criterion, which is used in well-known analogues. The new method is based on comparing the energy of signals reflected from a pipeline wall without a defect and with the presence of a defect (pitting).
The results of experiments show that the proposed method of pitting corrosion detection, based on echo energy analysis, allows to detect pits that are not identified by known methods of ultrasonic thickness measurement, and determine their depth.