Rationalization of the plant maintenance is one of the main topics being investigated in Japanese nuclear power industries. Optimization of the inspection and replacement period of equipments is effective for the maintenance cost reduction. The more realistic model of the replacement policy is proposed in this study. It is based on the classical replacement policy model and its cost is estimated. Then, to consider the inspection for the maintenance, the formulation that includes the risk concept is d...
英字タイトル:
Optimization on Replacement and Inspection Period of Plant Equipment

Abstract This study represents the evaluation results of the interval estimation for Weibull parameters m and 1 by the methods based on the conventional statistics and the Bayesia n statistics. The interval estimations by the conventional statistics are not necessarily reliable when a lot of failure data are not available. Both methods provide almost same i nterval estimation when a lot of failure data are available. This study also represents the evaluation results of the replacement intervals of equipmen...
英字タイトル:
Development of failure data and Maintenance Rationalization by Using Bayesian Updating

Abstract This study proposes the innovative method for evaluating the failure distribution functions that are essentially necessary to optimize the replacement interval of plant equipment. It is not easy to precisely evaluate the parameters of failure dis tribution functions since the enough failure data can not be easily obtained in Japanese plants. Then it is important to evaluate the confidence interval of the parameters of distribution functions to consider the risks due to the equipment failures. It i...
英字タイトル:
Revision of Failure Distribution Functions by Using Beyesian Statistics

Abstract This study describes the formulations to optimize the time interval of inspections and/or replacements of equipment/parts taking into account the probability density func tions (PDF) for failure rates and parameters of failure distribution functions (FDF) and evaluates the optimized results of these time intervals using our formulations by comparin g with those using only representative values of failure rates and the parameters of FDF instead of using these PDFs. The PDFs are obtained with Bayesi...
英字タイトル:
Optimization of Inspection and Replacement Period by Using Bayesian Statistics

1.緒言 ータに統合する手法と 専門家の知識の集約の言保全活動に 置までを含む て日常的な活保全活動は設計から建設、運転管理、廃棄措 置までを含めた生産活動全般を包括する極め て日常的な活動で、種々の設備や産業において 一般的に合意されている概念である[1]。 現在の 保全計画は保全技術者の経験と論理構成力に 立脚しているため、合理性を有する最適保全計 画を立案するには、自ずと限界があると考えら れる[1]。より体系化された保全学の手法を用い れば、例えば点検・検査に科学的・工学的理論 を適用して機器の点......
英字タイトル:
The Methods Integrating Expert's Experience into Scientific Maintenance Activities

保全の体系化について（第4回）－最適化プロセスにおける定量化手法－ 今野 隆博,Takahiro KONNO,笠井 雅夫,Masao KASAI,清水 俊一,Toshikazu SHIMIZU......

This paper provides the second part of the study on maintenance importance evaluation using the mathematical ‘Klee metho d'. In the second part of evaluation, a reevaluation is performed by the reference of the conventional qualitative eval uation results into the evaluation by the Klee method. As a conclusion of the whole study, additional way is considered as the better way against multiplicative way of Klee method in order to obtain better results on importance evaluation....
英字タイトル:
Maintenance Importance Evaluation Using Mathematical Method, Part 2

This paper provides the first part of the study on maintenance importance evaluation using a typical mathematical method called 'Klee met hod'. Klee method is a quantitative method and the results of the evaluation are compared with the conventional qualitative method. Actua l evaluation is performed on typical auxiliary pump parts of a nuclear power plant. As a conclusion of this study (Part 1), additional way is considered as a better way against multiplicative way of Klee method where the final conclusi...
英字タイトル:
Maintenance Importance Evaluation Using Mathematical Method, Part 1

1．はじめに原子力発電所の安全性・信頼性と経済性の最適点を求める「保全の最適化」が注目を浴びている中、発電所の設備機器の重要度に応じた適正な保全を行うことがより一層重要になってきている。前号の論文（その１）では、従来からある様々な重要度分類やクラス区分に加え、新たに“保全上の重要度”を考え、保全を 実施する場合の最小単位となる「部品」を対象にして、この保全上の重要度を『クリー法』というシステム評価手法と既存の定性的手法により評価（定性評価という）し、比較検討を行った［1］。本論文（その２）では、上記定性......

1．はじめに近年、原子力発電所の安全性・信頼性と経済性の最適点を求めることが重要との観点から、「保全の最適化」が注目を浴びている［1］。その大きなポイントの一つが、発電所の設備機器を『重点指向型保全』［2］の考え方に基づき、それら設備機器の"重要度"に応じた 適正な保全を行うことである。重要度にも、安全重要度分類、構造機種（クラス）区分、耐震クラス区分等、様々な分類／区分（定義）があるが、本論文では「保全」に着目することから、新たに"保全上の重要度"というものを用いることとする。保全上の重要度については、......