A Dynamic Risk Assessment Methodology for Maintenance Decision Support

Abstract

The failure mode and effect analysis (FMEA) is a widely applied technique for prioritizing equipment failures in the maintenance decision‐making domain. Recent improvements on the FMEA have largely focussed on addressing the shortcomings of the conventional FMEA of which the risk priority number is incorporated as a measure for prioritizing failure modes. In this regard, considerable research effort has been directed towards addressing uncertainties associated with the risk priority number metrics, that is occurrence, severity and detection. Despite these improvements, assigning these metrics remains largely subjective and mostly relies on expert elicitations, more so in instances where empirical data are sparse. Moreover, the FMEA results remain static and are seldom updated with the availability of new failure information. In this paper, a dynamic risk assessment methodology is proposed and based on the hierarchical Bayes theory. In the methodology, posterior distribution functions are derived for risk metrics associated with equipment failure of which the posterior function combines both prior functions elicited from experts and observed evidences based on empirical data. Thereafter, the posterior functions are incorporated as input to a Monte Carlo simulation model from which the expected cost of failure is generated and failure modes prioritized on this basis. A decision scheme for selecting appropriate maintenance strategy is proposed, and its applicability is demonstrated in the case study of thermal power plant equipment failures. Copyright © 2016 John Wiley & Sons, Ltd.

Fuzzy smart failure modes and effects analysis to improve safety performance of system: Case study of an aircraft landing system

“…Many methods available in the literature include max‐min Delphi method, similarity aggregation method (SAM), α‐cut, and arithmetic averaging operation. However, there is no evidence to show which method has enough superiority to compare with the other one . As mentioned earlier, experts generally prefer to express their opinion in qualitative terms.…”

“…However, there is no evidence to show which method has enough superiority to compare with the other one. 57,58 As mentioned earlier, experts generally prefer to express their opinion in qualitative terms. In this regard, ambiguity and uncertainty may arise during the risk assessment.…”

Introducing a heuristic approach to enhance the reliability of system safety assessment

“…Xu and Liao discussed that it is time‐consuming procedure, and sometimes the experts do not have enough motivation and lack interest to participate in this process with the tedious supervision. However, many scholars illustrate that using an interactive way has enough merits over the other methods …”

“…However, many scholars illustrate that using an interactive way has enough merits over the other methods. [49][50][51][52] In the last step, the collective experts' opinion with consideration of their importance weights should be aggregated to obtain the final output as possibility of the basic events. As mentioned in the literature, there are many methods introduced for this purpose such as simple averaging method, 53 similarity aggregation method, 3 and min-max.…”

A linguistic risk prioritization approach for failure mode and effects analysis: A case study of medical product development

“…It underlines the prevention of errors and thus aims at providing precautionary strategies rather than exploring a solution after the failures. With its distinctive characteristics, the FMEA technique has been applied for quality and reliability improvement in a variety of areas, such as health care risk management, equipment maintenance, gas refinery construction, knowledge management, and auto parts manufacturing …”