A background to shop floor control systems

Within batch production systems the lead time or throughput time for a batch through the shop floor is typically much greater than the processing time. It is not unusual for the actual processing (including set-up time) to represent less than five per cent of the total throughput time in conventional batch production systems. The throughput time or lead time is made up of four major components, the set-up time, the process time including inspection time, the transport time and the queuing time, as illustrated in Fig 1.1. In real life this latter component is frequently the largest, often representing in excess of 80% of total throughput time.