Fuzzy Based Breakdown Risk Evaluation of Engineering Facilities: A Case Study
Chidozie Chukwuemeka Nwobi-Okoye *
Anambra State University (Chukwuemeka Odumegwu Ojukwu University), Uli, Nigeria
Linda Nwaeto
Anambra State University (Chukwuemeka Odumegwu Ojukwu University), Uli, Nigeria
Stanley Okiy
Petroleum Training Institute, Effurun, Nigeria
*Author to whom correspondence should be addressed.
Abstract
Breakdown is an ever present risk in engineering facilities and infrastructure. Effective maintenance reduces such risks and improves reliability of facilities, plants and infrastructure. This study introduces a new method of accessing breakdown risk using fuzzy set theory. It involves identifying twenty maintenance variables responsible for breakdown and selecting four linguistic variables to identify the conditions of the variable. Four linguistic variables were equally identified for rating the consequence/importance of the maintenance variables to breakdown. A case study, a vegetable oil refining plant, was used to test the new method. An assessment form was used to gather the conditions of the maintenance variables in the plant. Fuzzifying the conditions ratings and the consequences and using fuzzy arithmetic; a condition rating of fair was obtained for the plant. The interpretation of the result implies that the plant is expected to operate with a low reliability and fairly high risk of breakdown.
Keywords: Breakdown risk, fuzzy sets, refinery, maintenance variables, risk assessment, modeling