A process flow is a sequence of processes and stock points through which entities pass in sequence. At the level of a flow, the performance metrics related to overall system performance are throughput, cycle time and work-in-process. Understanding relationships between these metrics and flow behaviour is most important part to improve process flow performance and design high efficiency flows. A system can perform completely differently under different conditions. By comparing flow performance in a present state with those in theoretically possible states that a system can reach, we can determine whether a process flow is good or bad. The research defines process flow performance metrics as well as their relationships, and suggests a method to evaluate process flow performance using the flow metrics. The outcome will provide an internal benchmark of a process flow and different routes for process flow improvement.
process flow, bottleneck rate, raw process time, critical WIP, practical worst case performance, internal benchmark