Affiliations: [a] Institute of Fluid Science, Tohoku University, Sendai
980-8577, Japan | [b] Fracture and Reliability Research Institute, Tohoku
University, Sendai 980-8579, Japan
Abstract: The feasibility of in-situ Eddy Current Monitoring (ECM) under high
temperature environment is discussed. For the purpose, an ECM experiment was
conducted at a System Safety Benchmark Facility (SSBF), which was designed and
constructed for assessing the crack growth behavior of welded pipes in a
Boiling Water Reactor (BWR) environment. The target for the monitoring was a
large-scale pipe specimen made of austenitic stainless steels 304, 304L and
316L, connected by weld joints of nickel based alloy 182 within the SSBF. Slits
were prepared at the Heat Affected Zones (HAZs) and weld lines from the inner
surface of the pipe specimen. Eddy Current Testing (ECT) probes were arranged
on the outer surface of the pipe specimen at the positions where the slits had
been introduced. After exerting the load, it was observed that the ECM
experimental signals changed. Subsequently, the numerical simulation of eddy
current signals based on the experimental conditions was carried out. As a
result of comparison between experimental and numerical eddy current signals,
it is shown that the in-situ ECM system makes it possible to observe crack
propagation in a BWR environment.
