Abstract This paper describes a new crack tip diffraction approach using a set of angle beam and direct contact transducers. In this approach, a crack height is calculated from a time di fference from two echoes of a tip-diffracted longitudinal wave, which arise after an incident wave from the angle beam transducer impinges the crack. The two echoes are detected by the d irect contact transducer which lies on the opposite surface of and over the crack. One echo is related to the wave traveling directly fro...
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Proposal of Concise Crack Sizing Approach in Ultrasonics

The nonflammable adsorbent AgX shows excellent adsorption characteristics of methyl iodide under harsh gas conditions like venting gas released from a nuclear power plant. Furthermore, it also exhibited good adsorption performances even in the temperature range of room temperature to 40 degrees below zero Celsius....
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Methyl iodine adsorption characteristics and applications of AgX in the outside air temperature range

The current edition of “Guideline of Inspection and Evaluation for Reactor Internals issued by Japan Nuclear Safety Institute (JANSI) consists of inspection target, inspection method, and evaluation. Recently, the guideline is revised based on the safety function of the Reactor Internals, domestic operation experience, and the new knowledge. In this report, summary of “Guidelines of Inspection and Evaluation for Reactor Internals [Core Shroud] and [Shroud Support]....
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Guideline for BWR Inspection Program Revision Policy of Guidelines for Core Shroud and Shroud Support

In recent years, inverter controlled rotating machines are becoming major for saving energy and maintenance labor. Up to now many kinds of methods about diagnosing rotating machines are proposed, but most of them are applicable only for machines rotating at constant speed. When rotating speed change, the acceleration signal measured for diagnosis becomes quite different. And applying the reviously proposed methods to invertercontrolled machines is difficult. So, in this paper, the method in which the diagno...
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Automatic Diagnosis Method for Inverter Controlled Rotating Machinery Using DP Matching, Histogram of Frequency Domain and Principal Component Analysis

The PD Center of Central Research Institute of Electric Power Industry (CRIEPI) commenced performance demonstration examinations (PD examination) for flaw depth sizing of austenitic stainless steel pipes in March 2006. At the end of FY 2015, 44 examination sessions have been completed and 58 candidates have passed the examination. The total number of PD examinee including re-tests and re-certification was 104. Passed candidates can perform depth sizing of SCC flaws with a high level of accuracy during ...
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Implementation report for 10 years after the start of Japanese performance demonstration examination

The PD Center of Central Research Institute of Electric Power Industry (CRIEPI) commenced performance demonstration examinations (PD examination) for flaw depth sizing of austenitic stainless steel pipes in March 2006. At the end of FY 2020, 54 examination sessions had been completed and 72 candidates had passed the examination. The total number of PD examinee including re-examination and re-certification was 124. Passed candidates can perform depth sizing of SCC flaws with a high level of accuracy. As a re...
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Current status of Japanese PD examination for 15 years

The 2011 off the Pacific coast of Tohoku Pacific Earthquake and the Tsunami gave the serious damage to the Fukushima-Daiichi Nuclear Power Plants (NPPs). The accidents occurred in Unit 1, 2, 3 and 4. It is said that the height of tsunami attacked Fukushima NPP was more than 14m. After 50 minutes from the automatic shut-down, tsunami a ttacked the NPPs in Fukushima Daiichi NPPs. For example, the Unit 1 lost A/C power caused the loss of water injection function; it made the core meltdown and unusual increase...
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Lessons Learned from the TMI-2 Accident and Chernobyl Nuclear Disaster for Nuclear SafetyInnovation

Our Company, aims at tracking huge plant parameters (Big Data), managed by Nuclear Power Plants. By application of this Big Data, along with NEC Corporation we developed a system to detect any equipment abnormalities accurately and as much as possible at an early stage. After the implementation of the system, checks of the actual working of the system can be conducted and performance gains enhanced drastically. ...
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Development of the Plant Monitor System utilized Invariant Analysis Technology and Big Data

BWR owners and plant fabricators have been making efforts to decrease the ISI parts where UT is difficult to be conducted. For that purpose, UT verification test for both detection and sizing qualification through deposit of pipe weld joint started in 2009 and will last until 2011. In 2009, UT verification test for stainless steel pipe weld joint has been performed. Test samples are stainless steel pipes with welds and sizes are 600A.350A.150A with EDM notches and/or SCC cracks. Angle beam methods and...
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Result of UT verification test for Stainless Steel through weld deposit

BWR owners and plant fabricators have been making efforts to decrease the ISI parts where UT is difficult to be cond ucted. For that purpose, UT verification test for both detection and sizing qualification through deposit of pipe wel d joint started in 2009 and will last until 2011. In 2009, UT verification test for stainless steel pipe weld joint has been performed. Test samples are stainless steel pipes with welds and sizes are 600A.350A.150A with EDM notches a nd/or SCCs. Angle beam methods and phased...
英字タイトル:
Result of UT verification test for Stainless Steel through weld deposit