Fuzzy Criticality Assessment of Systems External Corrosion Risks in the Petroleum Industry—A Case Study

Abstract

From the perspective of offshore installations, corrosion is the most common form of damage and the main factor affecting the longevity and reliability of assets. Maintenance plans based on risk and reliability are modern approaches. For a complex technical system such as a platform, maintenance management can use different approaches, such as reliability centered maintenance (RCM) that uses failure mode and effect analysis (FMEA) in determining the criticality of failure modes by the ranking of risks (e.g. related to corrosion rates and remaining life of the asset). However, in some practical cases, the implementation of the traditional FMEA may not be realistic due to the subjectivity of the dimensioning the risk factors. In this sense, this research aims to propose a more robust and practical methodology to assess the criticality of risks of external corrosion failures by the system. This methodology combines fuzzy scale method, risk space diagram and weighted Euclidean distance and is applied based on the perception of specialists in external corrosion. From an academic point of view, this research highlights the importance of using RCM for corrosion management in an empirical case. From the practitioner’s perspective, we seek to provide a tool, based on the RCM and the combination of fuzzy logic and multicriteria approach to rank systems to be inspected. Therefore, this new FMEA model can help to save time, cost and reduce fieldwork, considering gains related to quality, safety, technical efficiency in inspection and maintenance processes.