METHOD OF DETECTING PITTING CORROSION Russian patent published in 2020 - IPC G01N29/04 

FIELD: defectoscopy.

SUBSTANCE: use to detect pitting corrosion (pitting) in controlled articles by directed acoustic waves. Summary of invention consists in the fact that using ultrasonic piezoelectric transducers designed to conduct ultrasound thickness gauging of pipeline wall, starting pulse is generated and reflected echo signals are received through a constant distance-scan interval, a digitized oscillogram of the received echo signal is amplified, digitized and transmitted to the on-board computer on each piezoelectric transducer, digitized oscillograms are accumulated and averaged over two or more sounding cycles in each scan, measuring the time interval between the front of the emitted direct ultrasonic signal and the front of the received reflected ultrasonic signal from the inner surface of the pipeline wall, which forms the first echo signal, calculating the energy of the first echo signal, measuring time interval between front of first echo signal and front of received reflected echo signal from outer surface of pipeline wall, forming second echo signal, calculating energy of second echo signal, comparing the energy of the second A-scan second echo signal with the previous A-scans second echo energy values, detecting the third echo signal in the interval between the first and second echo signals, in the presence of the third echo signal, the energy of the third echo signal is calculated, the time interval between the maximum energies of the second and third echo signals is measured, and the depth of pitting is determined.

EFFECT: enabling detection of pitting corrosion by ultrasonic transducers designed to conduct ultrasound thickness gauging of a pipeline wall.

3 cl, 8 dwg