Ultrasonic signals at frequencies below 1 MHz have been used for the NDE of thick polymer samples. Coded signals such as chirps and bipolar Golay codes, together with pulse compression and signal processing, have been used to penetrate into thick sections of attenuating polypropylene riser stiffener material, using piezocomposite transducers to provide the required bandwidth. It is shown that this approach can be used to detect manufacturing defects such as air bubbles in flexible riser stiffeners, which might compromise their performance in the offshore oil and gas environments. © 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group
Ultrasonic NDE of thick polyurethane flexible riser stiffener material
LAURETI, STEFANO;RICCI, MARCO
2016
Abstract
Ultrasonic signals at frequencies below 1 MHz have been used for the NDE of thick polymer samples. Coded signals such as chirps and bipolar Golay codes, together with pulse compression and signal processing, have been used to penetrate into thick sections of attenuating polypropylene riser stiffener material, using piezocomposite transducers to provide the required bandwidth. It is shown that this approach can be used to detect manufacturing defects such as air bubbles in flexible riser stiffeners, which might compromise their performance in the offshore oil and gas environments. © 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis GroupI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
