Polyhedrika

Analyzing our Value Stream we identify a number of constraints that limit its effective capacity. The most visible constraints are the capacity of the different steps. But there are other, not so obvious, constraints such as the capacity variation of some steps. Process variation has been described as a virus infecting the value stream: it causes chaos and it is often undetected.     Dice Throwing Exercise A bottleneck limits the effective capacity of the whole line. Bottlenecks caused by variation are more subtle and difficult to detect and act upon. Process simulation can help us experience the effects of different types of constraints, try solutions and detect possible side effects. Process simulation helps us understand the value stream dynamic behavior: how variation affects key process metrics such as WIP, Lead time, Throughput, Cycle time, On Time Delivery, etc. Understanding these dynamic effects will enable us to get to the root cause of problems implementing def...

  Production based on forecast uses resources to produce items which will not eventually be sold while there is a shortage of those items the market actually demands. Demand lead times are getting shorter in most business while supply lead times are not able to keep pace. This often leaves just one alternative: "make to plan", also called "Push" logistics. The result is that in spite of our excess inventories we are unable to satisfy the demand: we have plenty of what nobody wants and no enough of what they want. "Make to order" or "Pull" logistics produces only what has been ordered by the customer so we avoid dedicating resources to produce unwanted items. The problem usually is lead time: can the customer wait until our supply chain is able to deliver? Kanban One way to implement "Pull" logistics is to use Kanban . A Kanban (Japanese for a card) is a token generated by the consumption of an item (or fixed lot of items) which authoriz...