Detecting pipe wall reduction using air-coupled MHz range ultrasonic wave

Monitoring Pipe-Wall Corrosion Rate by Ultrasonic Technique

thickness and corrosion/erosion rate. In this thesis, a combination of signal processing techniques are used to estimate the corrosion rate estimates based on MBE. Corrosion rate is estimated based on ultrasonic pipe wall thickness data is collected over a short period of time using MBE model. This technique is based on data collected from the speedometer applied for thinning and both indicate ...

Air-Coupled Nondestructive Evaluation Using Micromachined Ultrasonic Transducers

Nondestructive evaluation techniques Amlrurn , which use conventional piezoelectric transducers tvDicallv reauire liquid coupling fluids to improve " _ . the impedance mismatch between piezoelectric materials and air. Air-coupled ultrasonic systems can eliminate this requirement if the dynamic range of the system is large enough such that the losses a t the air-solid interfaces are tolerable. C...

Air-coupled Ultrasonic Testing of Materials

NDE Applications of Air-Coupled Ultrasonic Transducers

Abslract In recent years, several new NDE applications of air-coupled, as opposed to liquid-coupled, ultrasonics have been seriously pursued. The applications range from throughtransmission testing of aerospace laminates and various honeycomb or foam filled materials, and solar cells, to pulseecho flaw detection in plastic electronic packaging materials and in-line inspection of large-diameter ...

Long Range Guided Wave Pipe Inspection – the Advantages of Focusing

The use of synthetic focusing of torsional guided waves for detecting and sizing defects in pipes using an array of piezoelectric shear transducers clamped around the pipe circumference has been investigated. The performance of the focused system is tested and compared to an unfocused system using data from finite element simulations on pipes of different diameters with circumferential cracks; ...