Availability and cost-centered preventive maintenance scheduling of continuous operating series systems using multi-objective genetic algorithm: A case study

摘要

An effective maintenance system has to minimize the preventive maintenance cost or life cycle cost and maximizes the operating profit. Preventive maintenance cost increases when the preventive maintenance interval is short leading to more number of shutdowns. If the preventive maintenance interval is too long then also it increases the preventive maintenance cost since probability of failure increases. The objective is to have a balanced preventative maintenance interval so that preventive maintenance cost is minimized and the plant availability is maximized. Not many studies have been published that tackle preventive maintenance scheduling of a continuous operating series system where both maintenance cost and availability cost are simultaneously considered. This article proposes a multi-objective PMS optimization model for continuous operating coal-fired boiler tubes used in thermal power plant. 70% of the failures in these plants are due to failure of boiler tubes. The model is intended to minimize the PMC and maximize the availability. A multi-objective genetic algorithm is used that can optimize more than one objective functions simultaneously by searching globally and generating a set of solutions. (19 refs.)