In Japan, a performance demonstration (PD) system for certifying WOL inspection methods is being developed. The Japanese qualification requirements dictate that either real IGSCC or equivalent flaws that produce ultrasonic responses similar to IGSCC be used in the qualification test samples. Studies have shown that it is very difficult to control the growth of deep IGSCC in weld overlay samples, so the Japanese have selected an alternative flaw making process that is capable of produc ing equivalent respo...
英字タイトル:
The Ultrasonic Responses from Intergranular Stress Corrosion Cracking andother alternative flaws in Weld Overlay (WOL) Samples

The reliability of inspection results is affected by the skill of examination personnel, particularly with regard to manual ultrasonic testing (UT). The number and design of test specimens are among the most important points to be considered during training or assessing the qualification of UT examination personnel. In this study, we have developed a novel virtual UT system that simulates actual UT work for piping welds. This system (Tool for Realistic UltraSound Testing) consists of a dummy UT probe, ...
英字タイトル:
A prototype of the virtual UT test system for training of inspection engineer

In recent years, it has been reported that the primary water stress corrosion cracking (PWSCC) has occurred in dissimilar metal weld (DMW) components such as steam generator nozzle to safe end weld, reactor vessel nozzle to safe end weld, and so on, in PWR. The depth sizing of such cracks with high accuracy is important in order to ensure the reliable operation and life extension of nuclear power plants. Therefore, construction of the performance demonstration (PD) system for certifying DMW inspection ...
英字タイトル:
Investigation of Equivalency of Ultrasonic Response Relation between SCC and Non-SCC Crack in Dissimilar Metal Weld

In recent years, it has been reported that the primary water stress corrosion cracking (PWSCC) has occurred in dissimilar metal weld (DMW) components such as steam generator safe end weld, reactor vessel safe end weld, and so on, in PWR. The depth sizing of such cracks with high accuracy is important in order to ensure the reliable operation and life extension of nuclear power plants. Therefore, construction of the performance demonstration (PD) system for certifying DMW inspection method is being inve...
英字タイトル:
Investigation of Phased Array UT technique for Circumferential Crack Depth Sizing in Dissimilar Metal Weld

TEPCO’s Fukushima Daiichi Nuclear Power Station Accident caused severe accident to lose functions of many instrumentation systems. As a result, many important plant parameters couldn’t be monitored. In order to monitor plant parameters in the case of severe accident, new instrumentation systems available in the severe conditions are being developed. Water level in reactor pressure vessel and hydrogen concentration in primary containment vessel are one of the most important parameters. Performance test ...
英字タイトル:
Water Level Measurement System in Reactor Pressure Vessel of BWR and Hydrogen Concentration Monitoring System for Severe Accident