Abstract
Automatic manufacturing like machining centers can replace the worn cutting tool with a new edge in a short time within the setup time of a workpiece. In this situation no minimum-time speed exists as the usual machining. This paper aims to analyze the optimal machining speeds in this case under three kinds of evaluation criteria-minimum time (or maximum productivity), minimum cost, and maximum profit rate-and to inventigate the relationship between the optimal machining speeds obtained. The efficiency speed range is also examined. An example is demonstrated to explain the analytical results.