A lean-based ORR system for non-repetitive manufacturing

Lean implementations are no longer limited to high-volume production and are becoming increasingly common in low-volume, high-variety non-repetitive companies. Such companies, usually with make-to-order or engineer-to-order production, have normally been modelled with a job shop production system, but many of them actually have a dominant flow in production. Moreover, one of the main characteristics of lean implementation is that it streamlines production flow, makes it unidirectional and reduces setup and lot size. Consequently, a significant number of production systems are better modelled as flow shops, rather than as job shops. This has an impact on production management approaches, and in particular on order review and release systems. In fact, ORR systems have been designed with job shops in mind, because they are the most complex systems to manage, and because they are considered the optimal system for non-repetitive production. We believe that job shop designed ORR systems are not the best ones for flow shop systems. We consequently propose a new ORR system designed for non-repetitive production in flow shops and based on lean principles. The simulation campaign run to test the new model shows that it yields lower lead times and increases output.