RELIABILITY DESIGN OF INDUSTRIAL PLANTS USING PETRI NETS

This paper describes a reliability analysis tool for design or revamping of industrial plants. The methodology is based on Failure Modes, Effects and Criticality Analysis (FMECA) and stochastic-events simulation analysis through Petri nets. The input data for the analysis are collected by applying a FMECA technique to the industrial plants both in the design and in the revamping stage, obtaining useful information of events probability, occurrence and effects. The following step, i.e. the simulation of the system operation using Stochastic Petri Nets (SPN), makes it possible to calculate some important reliability parameters of the industrial plant, evaluating their change depending on maintenance policies on plant items. In particular, the effects of preventive maintenance on system reliability have been analysed using Petri Nets, allowing the costs/benefits analysis. The proposed methodology has been applied to the Integrated Gasification and Combined Cycle (IGCC) plant of API oil refinery in Falconara Marittima (Ancona, Italy), providing results that are consistent with the experimental reliability data, thus proving to be an effective decision-support tool for Reliability Engineering.