A stochastic alternating renewal process model for unavailability analysis of standby safety equipment. (July 2015)

• Record Type: Journal Article
• Authors: van der Weide, J.A.M.; Pandey, Mahesh D.
• Is Part Of: Reliability engineering & system safety. Volume 139(2015:Jul.)
• Page Start: 97
• Page End: 104
• Publication Date: 2015-07
• Subjects: Stochastic process -- Alternating renewal process -- Unavailability -- Inspection -- Failure rate -- Age-based replacement -- Safety systems -- Nuclear plants; Reliability (Engineering) -- Periodicals; System safety -- Periodicals; Industrial safety -- Periodicals; Fiabilité -- Périodiques; Sécurité des systèmes -- Périodiques; Sécurité du travail -- Périodiques; 620.00452
• DOI: 10.1016/j.ress.2015.03.005
• Languages: English
• ISSNs: 0951-8320

Abstract

Abstract: The paper presents a stochastic approach to analyze instantaneous unavailability of standby safety equipment caused by latent failures. The problem of unavailability analysis is formulated as a stochastic alternating renewal process without any restrictions on the form of the probability distribution assigned to time to failure and repair duration. An integral equation for point unavailability is derived and numerically solved for a given maintenance policy. The paper also incorporates an age-based preventive maintenance policy with random repair time. In case of aging equipment, the asymptotic limit or average unavailability should be used with a caution, because it cannot model an increasing trend in unavailability as a result of increasing hazard rate (i.e. aging) of the time to failure distribution. Abstract : Highlights: Analyzes unavailability as a stochastic alternating renewal process. Derives a renewal integral equations for computing instantaneous unavailability. Includes general distributions for failure and repair times. Analyzes unavailability under an age-based preventive maintenance policy. Shows average unavailability that cannot capture the equipment aging effect.