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An Optimal Age-based Group Maintenance Policy for Multi-unit Degrading Systems

Shafiee, Mahmood, Finkelstein, Maxim (2015) An Optimal Age-based Group Maintenance Policy for Multi-unit Degrading Systems. Reliability Engineering and System Safety, 134 . pp. 230-238. ISSN 0951-8320. (doi:10.1016/j.ress.2014.09.016) (Access to this publication is currently restricted. You may be able to access a copy if URLs are provided)

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In order to share maintenance set-up costs and reduce system breakdown, the group maintenance policies are widely used for complex multi-unit systems. In this paper, an optimal age-based group maintenance policy is proposed for a multi-unit series system whose components are subject to different gradual degradation phenomena. When the degradation level of a component reaches a given critical size, it is replaced by a new one and the other components undergo a preventive maintenance (PM) action; otherwise, a planned group PM is performed for the whole system at operational age T>0. The problem is to determine an optimal group maintenance time T⁎ such that the system’s average long-run maintenance cost per unit time is minimized. The explicit expression of the objective function is derived and sufficient conditions for existence and uniqueness of the optimal solution are obtained. Finally, the proposed maintenance policy is applied to a group of wind turbine bearings and the results are compared with the case without planned maintenance (i.e., reactive response) and with an individual age-based maintenance policy.

Item Type: Article
DOI/Identification number: 10.1016/j.ress.2014.09.016
Uncontrolled keywords: Group maintenance; Multi-unit systems; Degradation; Preventive maintenance
Subjects: T Technology > TA Engineering (General). Civil engineering (General) > TA165 Engineering instruments, meters etc. Industrial instrumentation
T Technology > TA Engineering (General). Civil engineering (General) > TA401 Materials engineering and construction
T Technology > TJ Mechanical engineering and machinery
V Naval Science > VM Naval architecture. Shipbuilding. Marine engineering
Divisions: Faculties > Sciences > School of Engineering and Digital Arts
Depositing User: Mahmoud Shafiee
Date Deposited: 27 Jan 2020 13:21 UTC
Last Modified: 06 Feb 2020 13:06 UTC
Resource URI: (The current URI for this page, for reference purposes)
Shafiee, Mahmood:
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