MODEL OF PREVEMTIVE MAINTENANCE AND MINIMAL REPAIR COSTS WITH INTEREST RATE

• Main Author: LEWAHERILLA (NIM : 20813012); Pembimbing : Dr. Udjianna S. Pasaribu; Dr. Hennie Husniah, NORISCA
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/20356
• Institution: Institut Teknologi Bandung

This thesis deals with minimal repair and sequential imperfect preventive maintenance (imperfect PM) for dump trucks which operated in open-pit mining. Failure that occur at random times rectified by minimal repair, result minimal repair cost. We adding the downtime cost to modify the cost model previously by Jiang and Murthy (2008). That cost is intended as a cost of losses when the truck repaired. Suppose is cost of minimal repair and downtime cost. While some imperfect PM performed on a schedule periodic, result imperfect PM costs, denoted by B. The expectation of the total maintenance costs is minimized are the result of , by maximize . Decision variable to optimize maintenance is a set of the number of imperfect PM action and the time of preventive action. The distribution of first failure rate is Weibull with shape and scale parameters 1.05317 and 0.19821, respectively. This is a kind of repairable system with the failure is nonhomogeneous Poisson process (NHPP). It was showed by the plot of hazard rate. Each dump truck is unique. So, the maintenance cost need calculated for each truck. Because of the time value of money, each cost should be subject to interest rate about 7-8%. Thus the future value of total maintenance cost could be prepared by company.