Optimal Overhaul â Replacement Policies For a Repairable Machine Sold with Waranty
This research deals with an overhaul-replacement policy for aÂ repairable machine sold with a free replacement warranty (FRW), which will beÂ used for a finite horizon T and evaluated at fixed interval s. At each evaluationÂ point, the buyer considers three alternative decisions, i.e. (1) keep the machine,Â (2) overhaul it, or (3) replace it with a new identical one. If the machine failsÂ during the warranty period, this is rectified at no cost to the buyer. Any failureÂ occurring before and after the expiry of the warranty is restored by minimalÂ repair. An overhaul-replacement policy was formulated using a dynamicÂ programming approach. The results show that overhaul rejuvenation may extendÂ the machine life cycle and delay the replacement decision. In contrast, theÂ warranty stimulates early machine replacement and in so doing increases theÂ replacement frequency for a certain range of replacement costs. This implies thatÂ in order to minimize the total ownership costs over T, the buyer needs to considerÂ the minimal repair cost reduction due to the rejuvenation effect of an overhaul asÂ well as the warranty benefit due to replacement. Numerical examples areÂ presented for both illustrating the optimal policy and describing the behavior ofÂ the optimal solution. Dibuat Oleh Â :Â Kusmaningrum Soemadi, Bermawi P. Iskandar, dan Â Harsono Taroepratjeka Alamat e-mail :Â kusmaningrum@itenas.ac.id Kata Kunci :Â dynamic programming, minimal repair, Â overhaul, replacement, Â warranty. Keterangan :Â Â Karya Ilmiah iniÂ dimuat pada Â Journal ofÂ Engineering and Technological Sciences, Vol. 46, No. 4, 2014, 465-483,Â 2014 Published by ITB Journal Publisher, ISSN: 2337-5779, Optimal Overhaul â Replacement Policies For a Repairable Machine Sold with Waranty