Decision-Making Support Systems for Reliability-Centered Maintenance.

Abstract

A Systematic Reliability Improvement (SRI) program has been developed to support the decision-making processes of preventive maintenance (PM) planning for enhancing plant/system reliability in nuclear power plants. The SRI program is based on improved information-handling methods in the Reliability-Centered Maintenance (RCM) methodology. This program enables us to select a proper PM plan using a computerized system that integrates the following three subsystems which have been developed and is implemented on an engineering work station.(1) The maintenance management support subsystem can provide statistical parameters which indicate the characteristics of the failure mode for components based on the statistical analysis of field maintenance data. (2) The FME/CA-database subsystem can manage the system/component failure modes and their characteristics which are estimated by experts at the design stage using 13 types of assessment rankings of the failure mode effects and criticality analysis (FME/CA). (3) The PM planning support subsystem can support decision-making in determining the priority of PM improvement plans using a new method combining the above FME/CA assessment rankings and interactive logic tree analysis (1-L TA). The effectiveness of the SRI program and its support systems has been validated through a feasibility study using simulated data on a primary loop recirculation system in BWR plants.

INCORPORATING UNCERTAINTY IN THE DESIGN OF STREAM CHMNEL MODIFICATIONS1

“…A slight modification of this technique referred to as Failure Modes, Effects, and Criticality Analysis (FMECA), can also be used in a similar way for monitoring in the post-construction phase. As with FMEA, FMECA is used to evaluate the importance of failure effects on a system's performance (Shimizu et al, 1993). The main point of note is the FMECA provides a basis for carrying out appropriate corrective action once failure has occurred while there is time for these actions to have significant impact on a proper system performance (McCollin, 1999).…”

“…In the past, FMEA has been used to advance the understanding of complex electrical and mechanical systems including numerous applications in nuclear safety (e.g., McCormick, 1981;American Nuclear Society, 1983;Fullwood and Hall, 1988;Henley and Kumamoto, 1992;Shimizu et al, 1993) and to evaluate and rank potential problems in manufacturing processes. Formulation of the FMEA begins with identification of the system and all of its components (Dushnisky and Vick, 1996).…”

A knowledge‐based system for preventive maintenance

“…This last subsystem represents an intelligent knowledgebased system designed to provide improved maintenance guidance on preventive maintenance intervals, tasks and inspection techniques based on the analyses yielded by the other two subsystems (Shimizu et al, 1993). IMOS, a prototype intelligent maintenance optimization system, was developed to assist in the evaluation and enhancement of maintenance routines.…”