Schematic diagram of the pulse defectoscopes (Descrydefect)

High-frequency generator forms a short pulses of alternating voltage and sends them to a piezoelectric vibrator. Vibrator converts these variations in the elastic vibrations of the same frequency. In contact with the part of the vibrator pulses of elastic vibrations come in metal and apply it as a slightly diverging beam. If the path of pulse propagation of elastic vibrations found defective, the part of the ultrasonic energy reflected from a defect reaches the probe, where the elastic vibrations are converted into an AC voltage.

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Industrial Engineering defectoscope:

Descrydefect ND 250a can monitor the long cylindrical parts (shafts, pipe, etc.) with automatic movement of the ultrasound transducer (probe) while rotating partsand flat slab according to the programmed algorithm.