Approach for Determining the Availability of Machine Tools Based on Skill Level of Operator and Service Personnel

Machine tools (MTs) availability is a critical measure for production scheduling. On the other hand, the machine tool availability depends on its reliability (mean time between failure, MTBF) and maintainability (mean time to repair, MTTR), which depends on multiple factors and uncertainties. One can consider the skill level of operators and service personnel that influence MTBF and MTTR of machine tools, which in turn can affect operating cost. The studies on the effect of the skill level of operators and service personnel on MT availability are limited. Generally, MT availability should be higher to maintain reasonable operating costs. In the current work, a multi-objective optimization (MOO) problem was formulated to maximize the MT availability and minimize the MT life cycle cost, considering the skill levels of the MT operators and service personnel. The results of this study help the management identify the skill level of operators and service engineers for maximum MT availability.