The distribution of eddy current is disturbed in the presence of cracks. An equivalent solenoid model and a loop current model were proposed respectively to model the bypasses of eddy currents to the underside and longitudinal end of a crack. Eddy current testing signals were qualitatively analyzed by using the equivalent current models. Simulation showed that the signal due to the bypass of eddy current to the under side of a crack was appropriate for the evaluation of crack depth, and the signal due ...
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Enhancement of Defect Sizing Ability by ECT Data Fusion

To validate the FEM simulation technique presented in the previous report, we made pipe butt welded joints between base metals of the same material SUS316L and between base metals of the dissimilar materials SUS316L and STPT370. Shot peening (SP) on the outer surface or the inner surface of these welded joints induces high compressive residual stresses on the surface. After heat treatment with the peak temperature of 623 K was applied to the welded joints, they retained high compressive residual stresses ...
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Evaluation of the sustainability of compressive residual stress by introduced a stress improvement method (the second report) ?Residual stress change of welded joint with shot peening by thermal cycle and stress loading.

When the steel structure is built such as nuclear power plant, residual stress occurs in or near the welding joint and it may cause the stress collision cracking(SCC). Therefore, as prediction of SCC, surface treatment such as the shot peening(following SP) is carried out in the weld, but the case analyzed about residual stress reforming by the SP does not exist. So, we developed the analysis method that can predict compressive residual stress relaxation behavior during shot peening by modelling dynami...
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Evaluation of the sustainability of compressive residual stress by introduced a stress improvement method (the first report) -Development of analysis method of the shot peening using idealized explicit FEM

The PIRT process was developed as a part of the systematic and documented means of demonstrating the validation of best estimate simulation codes in USNRC licensing of nuclear power plants. In this paper the PIRT process was applied for finding influential factors giving an impact on the accuracy of ultrasonic testing and eddy current testing and related problems required to improve the accuracy and also reports the results that the problems were ranked from the viewpoint of importance, knowledge and c...
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Accuracy of Non-destructive Examination Techniques to Detect Fatigue Crack

Phased array provides many advantages over conventional ultrasonic testing method, but phased array has also limitations. This paper describes typical results of the experimental sound field analysis generated from the array probe. A photo-elastic ultrasonic visualization technique was applied in this study. The so und field of shear wave generated from the array probe was equivalent to that from the fixed angle probe....
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Evaluation of Phased Array UT Conditions using Ultrasonic Visualization Technique

As one of plans to improve a skill of UT inspector, a methodo utilize ultrasonic waves predicted by UT simulation is su ggested. Therefore, modeling methods of metal microstructurebased on solidification simulation and the actual flaw dete ction conditions were developed, and UT simulation is carried out using the models. The validity in the simulation model is verified compared with experimental results. A method to apply simulation results to UT skill training is suggested....
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Application of FEM simulation for UT skill training

In ultrasonic testing for austenitic welds, it is generally said that the flaw detection in the weld is difficult because of spurious echoes by dispersion of the ultrasonic wave. Therefore, the ultrasonic examination personnel are required to have high level abilities to classify these echoes. It is important to train to maintain and improve the abilities. For the effective training, many samples are need with a variety of flaw characteristics and size. However, it is difficult to prepare such samples...
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Defect Model in TU simulation for UT training tool

1．はじめにオーステナイト系ステンレス鋼配管突合せ溶接部のき裂深さサイジング技量に関して、（社）日本非破壊検査協会規格NDIS0603「超音波探傷試験システムの性 能実証における技術者の資格及び認証」附属書（規定）「軽水型原子力発電所用機器に対するPD資格試験」［1］（以下、NDIS0603と記す）が制定され、国内でもき裂深さサイジングの技量の指標（測定誤差の判定基準）が示された。一方で、発電用原子力設備の低炭素ステンレス鋼管における健全性評価においては、現時点ではUTで測定したき裂深さに4.4mmを加算......

This paper describes two contents about reliability of crack depth sizing on ultrasonic testing. One is verification with appropriate acceptance cr iteria of the Japanese Performance Demonstration Code (NDIS 0603 Appendix) . Another is investigation about the true crack depth measurement method....
英字タイトル:
Reliability of Crack Depth Sizing on Ultrasonic Testing