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Ultrasonic Crack Inspection

Cracks and crack-like features can occur during pipe manufacture, pipeline construction or during operation. Whatever their origin, these flaws can seriously compromise the integrity of a pipeline, making it essential to detect, size and locate them before irreversible damage occurs. Cracks are often invisible to the eye, and can weaken a pipeline causing devastating failure.

NDT Global’s range of ultrasonic inspection tools ensure accurate identification of cracks and crack-like anomalies in the base material as well as in the weld area. In order to detect cracks, our ultrasonic crack detection tools, use the proven 45° shear wave method. The 45° shear wave is obtained in the pipe wall by applying the suitable angle of incidence in the liquid pipeline medium. If an internal or external anomaly is encountered in the material, the ultrasonic pulse is reflected and returned to the transducer. The location of the crack is calculated based on the signal time-of-flight, and depth is graded using signal amplitudes, signal overlap and other signal characteristics depending on the availability.

  • Sending ultrasonic pulse
  • Reflection and refraction at inner wall surface
  • Corner reflection at external crack
  • Receiving crack echo