1．緒言原子力発電所では、機器の交換、分解点検、検査、修理工事等において、さまざまな遠隔装置（ロボット） が使用されている。「ロボット」とはチェコスロバキアの作家チャペックの戯曲中の造語で、本来は機械仕掛けの人造人間を意味することは有名であるが、原子力発電所で実用化されているロボットは、人間が容易に近づけない放射線環境における遠隔作業化、作業者の被ばく低減、作業の効率化（定検期間の短縮）、作業の信頼性向上（機械化）等を目的に開発、導入されてきた。日立においても、古くは各種の交換装置等、狭隘部で大型機器を取......

1．はじめに近年、沸騰水型原子力発電所（以下BWRという） の原子炉再循環系（以下PLRという）配管溶接部で応力腐食割れ（Stress Corrosion Cracking、以下SCCという）が多数確認された。これらの配管の材質は、低炭素ステンレス鋼（SUS316（LC）材）であり、材料を低炭素化することにより、鋭敏化による応力腐食割れは生じないと考えられていたが、その後の実機材料調査結果や実験等により、表面が硬化すると粒内型応力腐食割れ感受性が上昇し、BWR 炉水模擬環境中にてき裂進展試験を行うと、粒界......

地震を受けた機器における塑性ひずみ検出方法の適用について 米谷 豊,Yutaka KOMETANI,伊東 敬,Takashi ITO,野中 善夫,Yoshio NONAKA,高木 愛夫,Yoshio TAKAGI,黒崎 裕一,Yuichi KUROSAKI,羽鳥 正訓,Yoshio TAKAGI, １．はじめに東京電力株式会社　柏崎刈羽原子力発電所は、2007年7月16日に発生した中越沖地震により被災したが、原子炉は安全に停止するとともに、耐震設計グレードの高い機器では外見上の損傷は認められなかった。ま......

Inspection results and building simulation analyses after the Tohoku Earthquake of March 2011 show that Unit 2 reactor building in the Onagawa Nuclear Power Station was secure enough during the earthquake. However, the data also indicate that the seismic response of the operating floor (top floor of the building) is relatively high compared to that of other stories because operating floors have fewer earthquake-proof members so that they can secure large space; therefore, we conducted seismic retrofit...
英字タイトル:
Improving Construction of Earthquake-Resistant Walls and Others in Unit 2 Reactor Building of Onagawa Nuclear Power Station

The aim of this study is to research and evaluate new technologies i n the world from the point of view to improve the safety and securi ty of pipeline for gas distribution toward the next generation which can practice the productive maintenance and preventive maintenance....
英字タイトル:
Research and Evaluation of New Technologies to Improve the Maintenance of Pipeline for GasDistribution toward the Next Generation

The aim of this study is to research and evaluate new technologies in the world from the point of view to improve the safety and security of pipeline for gas distribution toward the next generation which can practice the productive maintenance and prevent ive maintenance. ...
英字タイトル:
Research and Evaluation of New Technologies to Improve the Maintenance of Pipeline for GasDistribution toward the Next Generation

After Niigata-ken Chuetsu-Oki Earthquake happened, some deformations were found at buried part s of circulating water pipes at Kashiwazaki-Kariwa Nuclear Power Plants. We had evaluated the soundness of deformed pipes, and concluded that the degree of deformations is small enough to use these pipes continuously. In this paper, some results of these evaluations are described....
英字タイトル:
Evaluation of Soundness for Circulating Water Pipes

The nuclear reactor regulation law was amended three years ago (2012). In this amendment, the operation period of the commercial nuclear power plants in Japan was limited to 40 years. This limit may produce various problems in plant life management. So this paper proposes several recommendations for improvement. ...
英字タイトル:
Recommendations related to the Problem of Limiting the Life of Japanese Nuclear Plants to 40 Years

The framework of intelligent support system for the maintenance of nuclear power plant is proposed in this paper with emphasis on the combined use of a portable device and intelligent information processing. The purpose of this system is the realization of flexible inspection process and effective diagnosis process to be performed on-site. The prototype system has been implemented for the experimental facility with mobile-agent technology and PDA (personal digital assistant) to show the basic function...
英字タイトル:
Development of Maintenance Support System using Portable Device and Mobile Agent

High active liquid waste is stored in the facility equipped with cooling system and hydrogen scavenging system because of hydrogen generation due to radiolysis, and heat generation due to decay heat. The facilities related to these systems maintenance have been designed to be fed by emergency power generators in the conventional design. In addition to that, in light of the lessons learned from accident at the Fukushima daiichi nuclear power plant, we took safety measures for emergencies such as securem...
英字タイトル:
Emergency safety measures at the Tokai reprocessing plant（Part 1）