Harpreet Kaur,Reetu Malhotra,



Statistical Model,Stochastic Systems,Reliability,Availability,Manufacturing,Innovation,


The authors propose a stochastic analysis of a two-unit standby autoclave system with variable demand and inspection in this work. The autoclave system consists of a primary and a redundant unit, a dynamic demand profile, and an inspection mechanism to evaluate their condition. Inspection lowers the possibility of unanticipated failures and avoids financial loss. Best of our knowledge, many of the studies assume that the unit in cold standby mode is always reliable. This hypothesis lacks practical justification. Practically, its performance deteriorates due to environmental issues (dust, moisturizer, etc.). The authors found the same when visiting a ghee manufacturing plant in Punjab. Additionally, weather fluctuations also affect the production (as demand for ghee is higher in winter as compared to summer). Behaviour of redundant units is an intriguing aspect of this study and demonstrates its uniqueness. Thus, the authors explored two-unit standby autoclave systems subject to inspection on standby units with fluctuating demand. In the model, the main autoclave directly goes under repair when it fails, but the redundant autoclave undergoes inspection afterward beyond the determined redundant time, to check its possibility for repair or replacement. Replacement means a change of subparts, like Gear Box, etc., in an autoclave to put it in a working state instantly. Inspection adversely affects the system's reliability. Therefore, the statistical inference under the proposed innovation shows better results and a significant balance between the reliability and economy of the given stochastic system using the semi-Markov process (SMP) and regeneration point technique (RPT). By studying various scenarios about repair prices, inspection frequency, and fluctuating demand patterns, this research provides vital insights into the most effective approaches for handling redundant units and preserving system functionality.


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