According to the past edition of “Guideline of Inspection and Evaluation for Core Internals (Core Spray Sparger & Piping Jet Pum p]” issued by Japan Nuclear Technology Institute (JANTI), fully penetrated flaw should be assumed for uninspected region, for ev aluating their integrity. This assumption was considered to be too conservative. Then, this study was performed on the better as sumption of flaw existence in the uninspected region to develop more appropriate flaw modeling by using statistical evaluati...
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The Guideline of BWR Inspection Program Study on Flaw Characterization of Core Internals Piping for Uninspected Region

Baffle Former Bolts (BFBs) in PWR nuclear plant have the possibility to be cracked due to Irradiation Assisted Stress Corrosion Cracking (IASCC). The maintenance guideline for BFBs had been established from Thermal and Nuclear Power Engineering Society in 2000, and BFBs have been maintained in accor dance with this maintenance rules. Recently, the new edition of this guideline has been published in order to reflect latest IASCC data and more preci se stress evaluation of BFB into maintenance rules. The su...
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Improvement activities for the maintenance of Baffle Former Bolts

Water environment improvement (ex. Hydrogen Water Chemistry (HWC)) is carried out for Stress Corrosion Cracking (SCC) mitigation in some of BWR plants. Japan Nuclear Technology Institute (JANTI) has the guideline on the inspection programs based on effectiveness of environmental SCC mitigation technique for BWR core internals. The guideline provides the crack growth rate (CGR) under HWC. Although CGR is defined by ECP (electroch emical corrosion potential), a dealing of evaluation of ECP and the HWC avail...
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The Guideline of evaluating the effectiveness of environmental improvementby Hydrogen Water Chemistry

The guideline committee for the inspection and evaluation of Reactor Vessel Internals of JANSI (Japan Nuclear Safety Institute) has been developing many guidelines based on principle which the conservative methodology, and covered both individual inspection method of reactor internals and application of repair methods for reactor internals. In this paper, some aspects of the JANSI-VIP-21 (Guidelines for the inspection and evaluation of Reactor Vessel Internals, revised Mar.2017) which is summary document o...
英字タイトル:
Outlines of Guidelines for the Inspection and Evaluation of Reactor Vessel Internals

“The guideline committee for the inspection and evaluation of Reactor Vessel Internals” of JANSI (Japan Nuclear Safety Institute) has been developing many guidelines based on principle which the conservative methodology, and covered both individual inspection method of reactor internals and application of repair methods for reactor internals. In this paper, some aspects of the JANSI-VIP-03 (Guidelines for the inspection and evaluation of Reactor Vessel Internals, revised Dec.2013) which is summary docu...
英字タイトル:
Outlines of Guidelines for the Inspection and Evaluation of Reactor Vessel Internals

“The guideline committee for the inspection and evaluation of Reactor Vessel Internals” which was established in 2000 and transferred to Japan Nuclear Safety Institute in Nov.2012, developed many guidelines based on valid technical basis. These guidelines were made in principle which the conservative methodology, and covered both individual inspection method of reactor internals and application of repair methods for reactor internals. In this paper, overview of the activity is introduced. ...
英字タイトル:
Outlines of Guidelines for the Inspection and Evaluation of Reactor Vessel Internals