Electromagnetic Acoustic Transducer Techniques for Inspection of OCTG Pipes Along with DC Magnetic Flux Leakage Testing and Magneto-Inductive Material Characterization - A Complete Water-Free Solution

摘要

This paper discusses EMAT as a technique to produce ultrasonic waves in ferrous materials. Ultrasonic as an NDT method is known to most of us. Independent of how the ultrasonic waves are produced, the physics of their propagation, transmission, reflection and absorption remain exactly the same. This paper will, therefore, not discuss any of these phenomena. Conventionally, ultrasonic waves are produced using piezoelectric materials. These piezoelectric materials, when subjected to an excitation voltage, expand and contract depending on the polarity of the applied voltage. This expansion and contraction creates compression waves in the material.