Title: Optimal number of runs for unreliable equipments under uncertain conditions in the 'public utilities'
Authors: M. Amiri
Addresses: Research Institute of Petroleum Industry, West Blvd., Near Azadi Sports Complex, Tehran 1485733111, Iran
Abstract: Utility enterprise (UE) appears as a business strategy for small, medium-sized and large utilities. However, to support the operations of a UE, preventive maintenance (PM) timetable under the real conditions is considered to be the most significant scheduling in the contemporary public utility industries. Running equipment should be assumed to worsen when it is in operation, along with increment in the rate of failure. In this research, we come up with a model that is useful to determine the optimal number of cycles and the sequence of preventive maintenance schedules that minimise the long time cost. The equipment is subjected to preventive maintenance either on failure or after having reached an anticipated age, which of them happens first. Some useful factors of the cost function are developed to characterise the optimal policy. The paper encompasses the beneficial aspects of the new system implementation in a transportation company.
Keywords: public utilities; preventive maintenance; imperfect maintenance; integrated models; unreliable equipment; uncertainty; modelling; scheduling; sequencing; maintenance schedules; transport industry.
International Journal of Collaborative Enterprise, 2013 Vol.3 No.4, pp.252 - 268
Received: 17 Jul 2012
Accepted: 14 Mar 2013
Published online: 12 Jan 2014 *