Development of an Electromagnetic Acoustic Transducer for Inspecting the Wall Thickness of Offshore Risers from the Inside
The design requirements for an electromagnetic acoustic transducer to determine remaining wall thickness of offshore gas risers from the inside are presented, together with the results of evaluation of a prototype. A specially designed configuration of high-energy-density permanent magnets, the choice of dedicated emitter/receiver coils and impedance matching between coils and electronics have resulted in optimum ultrasonic performance. Aspects related to implementation in an inspection vehicle, such as mechanical protection and negotiation of local obstructions inside a riser pipe, have received special attention and will be discussed.
KeywordsMagnet Pole Pipe Wall Receiver Coil Test Loop Local Obstruction
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