This paper discusses an improvement of the quantitative method to evaluate the reliability for the naintenance plan with respect to the risk impact both for CDF (Core Damage Frequency) and Plant T rip requency. The quantitative approach includes the considerations for the effect of the Condition Based Taintenance (CBM) changing in addition to the Time Based Maintenance (TBM), and the reliab ility for the naintenance plan is evaluated using component failure rate which is presumed from experimental naintena...
英字タイトル:
A Study for the Reliability Evaluation Method for the Maintenance Plan Using the Risk Information II? Part 2: An application example of the evaluation method of failure ratebased on degraded state analysis of component part ?

1. 緒言原子力発電プラントには高い信頼性と安全性は勿論 のこと、設備利用率の向上と保守費削減による発電原 価の低減が強く求められている。プラント機器の保守 に関しては、従来は信頼性維持のために一定周期で点 検を実施する時間計画保全方式が採用されてきたが、 近年では保守費削減と両立するために多くのプラント で機器の運転監視に基づいて点検の要否を定める状態 監視保全方式への移行が進められている[1]。状態監視保全の運用にあたっては、 ・ 状態監視保全の適用が可能で効果的な機器の選定 ・ 監視パラメータの選定......
英字タイトル:
Application Strategy and Support System for Optimizationof Condition Based Maintenance

１．はじめに日本電気協会「原子力発電所の設備診断に関する技術指針－放射線肉厚診断技術(JEAG4224)」は、原子力発電所の機器・設備の放射線ラジオグラフィ(IP*1、カラーI.I. *2)を用いた肉厚診断を規定している。特に、本指針は「減肉の兆候」をとらえようとするものである。日本電気協会の設備診断指針には、本指針の他に、回転機械振動診断技術(JEAG4221)、潤滑油診断技術(JEAG4222)、赤外線サーモグラフィー診断技術(JEAG 4223)がある。これらは、一般産業界では広く活用されてきて......

We have been developing a system equipped with a mixture of hundreds of sensors for temperature, strain, and vibration. Previously, we confir med that the system could interrogate 192 points FBG sensors using a combination of time division multiplexing (TDM), waelength division mult iplexing (WDM), and an algorithm to measure the static and dynamic signal with one system. We a field test is performed and since it confirme d having formation nature as a multipoint apparatus surveillance system of 192 points...
英字タイトル:
Optic fiber of apparatus surveillance system with Condition based maintenance

Abstract In operation of nuclear power plants (NPPs), it is required not only to preserve and improve the reliability and safety, but also to introduce more efficient and lower cost maintenance strategy simultaneously, due to the power trading deregulation in recent years. For this purpose, Condition Based maintenance (CBM), which has been extensively applied i n the nuclear power plant of U.S., is introduced as a maintenance method for rotating machines in Japanese nuclear power plant. TOSHIBA develops t...
英字タイトル:
Development and application of Monitoring and Diagnosis Techniques for Condition Based Maintenance in Nuclear Power Plant

The authors developed an online method to monitor the condition of sensors implemented in Nuclear Power Plants. The method employs Sequential Probability Ratio Test (SPRT), and calculates log-likelihood function of each sensor readings obtained through the plant process computer to determine whether the value of the l og-likelihood function exceeds a statistically defined setpoint. A study on data collected during startup testing of a BWR power plant showed that the method wa s applicable for 1824 sensors...
英字タイトル:
Online Monitoring of Nuclear Power Plants Instrumentation

This paper introduces the simply applicable vibration diagnostic technique to a vertical type pump in nuclear power pla nts. This technique is the combination of simple shaft vibration measurement by an ultrasonic vibrometer and a rotor dy namics simulation. By using this technique, for vertical type pump, a simple and high-precision diagnosis is attained. It is expected that this technique has effect in cost reduction and improvement of reliability in nuclear power plants....
英字タイトル:
Vertical type pump diagnosis using an ultrasonic vibrometer

As use of condition-based maintenance is allowed in the new regulatory inspection system employed in Japan's nuclear pow er plants in 2009, development of advanced diagnostic technologies for motor-operated valves (MOVs) is now required. This report discusses advanced technologies in valve-setup verification, valve performance evaluation, monitoring of valve/ac tuator conditions by performance diagnostic system and moreover detection of stem crack by ultrasonic diagnostic system....
英字タイトル:
Development of Advanced Diagnostic Technologies for Motor-operated Valves