Modelling of wear defects under an external object for the ECT of SG tube

Edouard Demaldent (1) , Christophe Reboud (2) , Audrey Vigneron (3) , Frédéric Nozais (4) , Jean- Baptiste Boy (4) , Thierry Sollier (5)

1 LSMA (CEA, LIST) - Laboratoire Simulation et Modélisation Acoustique (CEA, LIST)
2 LSME (CEA, LIST) - Laboratoire de Simulation et de Modélisation Électromagnétique (CEA, LIST)
3 LMC (CEA, LIST) - Laboratoire Méthodes CND (CEA, LIST)
4 LIC (CEA, LIST) - Laboratoire Instrumentation et Capteurs (CEA, LIST)
5 IRSN/PSN-EXP/SES/BECM - Bureau d'Expertise des Contrôles non destructifs et des matériaux

The vibration of the tubes in steam generators (SG) causes fretting-wear, especially in the tubes bended parts near anti-vibration bars (AVB). Similar degradations, with more unpredictable shapes, can also be caused by foreign objects, like a welding rod located in the secondary area of the SG for example. This joint study between CEA LIST and IRSN aims at efficiently simulating eddy current testing (ECT) signals due to fretting-wears. For this purpose new advanced geometric tools feed the 3D models developed by the CEA LIST allowing to quantify the influence of the various geometric parameters of the configuration. In particular, we want to verify the ability of usual simplified geometric representations to approximate these signatures (typically with a rectangular notch in a straight tube to represent the wear under AVB). This numerical study is accompanied by numerous experimental acquisitions on machined tubes, with and without external object.

Mots clés: Eddy current testing ECT; modelling; boundary element method

Domaines: Modélisation et simulation

Edouard Demaldent, Christophe Reboud, Audrey Vigneron, Frédéric Nozais, Jean- Baptiste Boy, et al.. Modelling of wear defects under an external object for the ECT of SG tube. 12th European Conference on Non-Destructive Testing (ECNDT 2018), Jun 2018, Gothenburg, Sweden. pp.ISSN 1435-4934. ⟨hal-04554004⟩