Selection Principles on Manufacturing System for Part Family

In the mid-to-large volume manufacturing operations, a Single Part Manufacturing System (SPMS) is usually used to produce one part model. As the progress of manufacturing technologies, modern manufacturing systems such as reconfigurable manufacturing systems (RMS), are more capable of producing a family of part models, such a system is often referred to as a Multiple Parts Manufacturing System (MPMS). Therefore, given a number of part models within the same part family and their respective volumes, which system style is more economical will be a challenging question for system designers. To answer this question, this paper develops two sets of selection principles on manufacturing systems for part family. Firstly a cost model is constructed to account the investment on machine tools, material handling and transfer equipment as well as other devices utilized in a manufacturing system. Several selection principles are developed based on this model which captures the cost difference between SPMS and MPMS. Then a concept of utilization rate of a SPMS is initiated. Another set of selection principles based on the average utilization rate of the SPMSs are developed to assist the system designers in determining whether a MPMS should replace the SPMSs.