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Published: 6 September 2017

Reliability, Availability, Maintainability,
Safety/ Supportability/Sustainability/Survivability

Each engineering asset (product, plant or infrastructure) is unreliable in the sense it degrades with age and usage and will fail ultimately. When a failure occurs, the severity of the consequences can be very significant, leading to higher maintenance, cost, and reduction in availability, economic loss, damage to the asset and environment and possible loss of human lives. Unreliability may also lead to annoyance and inconvenience leading to a lasting customer dissatisfaction that can create serious problems for the company’s marketplace position and reputation.

Reliability science deals with the understanding of the degradation processes and reliability issues in the design stage. Reliability economics takes care of cost analysis of issues relating to design for reliability, and maintenance development. Reliability technology looks into technologies to sense and monitor the system degradation, to collect and analyze relevant data for decision making. Reliability theory provides a tool to deal with all facets of reliability, engineering including maintenance, life cycle cost/profit and management. Effective maintenance theory and practice is applied to compensate the shortcoming in reliability to bring it upto the desired level by taking care of technological and economic issues. Maintainability deals with maintenance issues during the design stage, with an objective to facilitate easy and cost effective maintenance strategies so that the desired reliability can be guaranteed. Maintenance actions, if used properly can control the degradation and reduce or eliminate the likelihood of the occurrence of failures and to restore a failed system to its operational state. However, maintenance activities involves costs and these can be a significant percentage of the operating budget; like, around 5% in manufacturing industry, 10-15% in aviation industry, 15-20% in transport and 30% in mining industry. Safety assessment of engineering objects forms the foundation for robust investigation of the risks associated with failures. The effectiveness of preventive and mitigating failure measures supports decision making regarding safety performances. Reliability, Availability, Maintainability and Safety RAM4S is a ethodology that deals with function preservation and failure prevention during the design and operation phases of the asset’s life cycle. The Division of Operation and Maintenance Engineering at Luleå University of Technology has been active in various aspects of RAM4S Engineering. These include (i) reliability evaluation of repairable and non-repairable units, (ii) remaining useful life estimation, (iii) maintenance optimization and decision modeling, (iv) diagnostic and prognostic, (v) condition monitoring and (vi) spare parts management. These have been applied in several different industrial sectors such as, aerospace and aviation, rail transport, mining, paper manufacturing, and process industry. The aim of RAM4S program at Luleå University of Technology is to provide a platform to integrate and support RAM4S related researches and competencies to assist the transfer of this knowledge to different industry sectors.