Convertibility and Productivity of Manufacturing System Configurations

Conversions between different products manufactured on the same system often require time-consuming shut-downs and thus, incur productivity losses. Producing multiple products on the same line complicates system productivity analysis because production rates, failure rates, and repair rates vary between different part types. Certain manufacturing system configurations have advantages when convertibility is considered. Ideally, manufacturing lines that produce a mix of products or undergo a product rollover would not see any loss in production relative to lines that continuously produce a single product throughout the system lifetime. This paper investigates the interactions between convertibility and productivity for different manufacturing system configurations, using analytical methods. The methods presented in this paper can be applied to assembly or machining stations in dedicated, flexible, or reconfigurable manufacturing systems. When designing such systems, it is important to recognize that more convertible systems are more productive over the long-term, as product designs change.