Enhancement of Nondestructive Evaluation Technique for Magnetic and Nonmagnetic Structural Components

JNC TN9400 2000-021, 104 Pages, 2000/03

JNC-TN9400-2000-021.pdf:5.21MB

ln this report, research works performed in the Structura1 Safety Engineering Group of OEC/JNC are summarized as the final report of the doctoral fellowship. The main objective of this study is for the enhancement of the nondestructive evaluation techniques for structural components of both magnetic and nonmagnetic material. Studies in three topics have been carried out aiming at the quantitative evaluation of crack with the eddy current testing and the validation of a natural magnetic field based NDE method for detecting mechanical damages in a paramagnetic material. ln the first part of the study, an approach to the reconstruction of the natural crack was proposed and implemented with an idealized crack model for its validation. ln the second part, the correlation of the natural magnetization and the mechanical damages in the SUS304 stainless steel was investigated by using an experimental approach. ln part 3, an inverse method of the measured magnetic fields is proposed for the reconstruction of magnetic charges in the inspected material by using an optimization method and wavalet. As the first work, an approach to the reconstruction of an idealized natural crack of non-vanishing conductivity is proposed with use of signals of eddy current testing. Two numerical models are introduced at first for modeling the natural crack in order to represented it with a set of crack parameters. A method for the rapid prediction of the eddy current testing signals coming from these idealized cracks is given then by extending a knowledge based fast forward solver to the case of a non-vanishing conductivity. Based on this fast forward solver, the inverse algorithm of conjugate gradient method is updated to identify the crack parameters. Several examples are presented finally as a validation of the proposed strategy. The results show that both the two numerical models can give reasonable reconstruction results for signal of low noise. The model concerning the touch of ...

Development of eddy-current in-service inspection system for FBR steam generator tubes; Establishment of the set parameters for off line data analysis

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PNC TN9410 97-087, 142 Pages, 1997/07

PNC-TN9410-97-087.pdf:5.29MB

Computer data analysis is planned as an essential process to facilitate and speed up the ISI of MONJU steam generator tubes using the ECT technique. This process compares the phase and amplitude of the signal in a vector window in order to identify and categories defects. The categorization of the inspection signal requires a high level of precision. The analysis test was carried out taking the best operational conditions for reference. From this, the most accurate classification conditions were established. The MONJU PSI signal data was used to check the effectiveness of the process. The results are as follows. (A) Verification of the set parameter for off line processing. Automatic classification is possible for almost all the support plate signals. Classification of all the weld and bend signals was not possible. Therefore, the set parameter was selected for the category in which there were the largest number of signals was established. (B) Verification of the analysis processing conditions. The established analysis conditions allow automatic classification for about 80 to 85% of the signal comparison factor cases. Furthermore, it is possible to classify all the signals by additional operator intervention. In this way it is possible to analysis and evaluate all the MONJU steam generator tube ISI data. (C) Improvement of the data base. Evaluation of MONJU PSI flaw detection data was carried out by set parameter analysis. FOllowing these results the necessary data base for ISI signal evaluation was created.

Eddy current testing using by a parallelogram probe of the distorted magnetic flux detection type

; *; Ara, Katsuyuki

Nihon Oyo Jiki Gakkai-Shi, 20, p.633 - 636, 1996/00

https://doi.org/10.3379/jmsjmag.20.633

no abstracts in English

Flaw detection characteristics of eddy current parallelogram probe for detection of magnetic flux disturbed by a flaw

; *; Ara, Katsuyuki

MAG-95-77, 0, p.39 - 46, 1995/06

no abstracts in English

Development of eddy current testing method with detection of disturbed magnetic flux

; *; Ara, Katsuyuki;

MAG-94-225, 0, 8 Pages, 1994/12

no abstracts in English

The Second eddy current testing of zircaloy tube samples from the OECD Halden Reactor Project at Reactor Fuel Examination Facility,Tokai,JAERI

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JAERI-M 86-106, 42 Pages, 1986/07

JAERI-M-86-106.pdf:2.34MB

no abstracts in English

Detection and sizing of inside-surface cracks in reactor pressure vessels

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Karyoku Genshiryoku Hatsuden, 35(2), p.111 - 121, 1984/00

http://ci.nii.ac.jp/naid/40000525028

no abstracts in English

渦電流探傷用プローブ及び渦電流探傷装置

山口 智彦; Mihalache, O.

not registered

JP, 2019-062223  Patent licensing information  Patent publication (In Japanese)

【課題】配管の内面及び外面に形成された微小欠陥や欠陥形状を的確に検出することができる渦電流探傷用プローブを提供する。 【解決手段】渦電流探傷用プローブ1は、本体2の第1の中心軸O1に沿って、直接磁場を利用した第1の渦電流探傷系3と、間接磁場を利用した第2の渦電流探傷系4とを備える。第1の渦電流探傷系3は、第1の中心軸O2と平行な軸方向に並列して配置された一対の励磁兼検出コイル30A、30Bを備え、第2の渦電流探傷系4は、一対の励磁兼検出コイル30A、30Bの軸方向外側にそれぞれ配置された一対の検出コイル群41A、41Bと、一対の検出コイル群41A、41Bの軸方向外側にそれぞれ配置された一対の励磁コイル40A、40Bとを備え、一対の検出コイル群40A、40Bの各々は、第1の中心軸1を中心として周方向に所定の間隔でそれぞれ配置された複数の検出コイル400A、400Bにより構成されている。