PULL / KANBAN / FIFO

Pull Systems are the production of items only as demanded for use or to replace those taken for use.

Normally, units are transported or moved to the next production stage as soon as they are ready.

In a Pull System this is reversed; each production stage must be required to go back to the previous production stage to signal its readiness and pick up the exact number of units needed.

  • A Pull System limits the amount of Work–In–Process (WIP) inventory in order to control cycle time and lead time.

  • A Pull System establishes WIP CAP on the amount of inventory within a predefined physical work area or process.

  • To maintain the WIP cap, ‘exits’ from the process signal ‘starts’ into the process.

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Kanban establishes strategically located and managed buffers of parts with a process, for example

  • Raw material

  • Manufactured Parts

  • Purchased Parts

  • Finished Goods

  • Paperwork and business items

Parts replenishment is signaled based on consumption.

FIFO stands for FIRST IN – FIRST OUT.

It is a simple way to define both the material flow and information flow

  • A FIFO lane helps when two or more process have different cycle times

  • FIFO provides prioritization for items in a queue and improves throughput of the production line

  • FIFO can improve utilisation and throughput of a line when a process will take longer or shorter than average

  • FIFO will prevent earlier orders from being delayed in favor of newer orders which would result in increased lead time

  • FIFO is used when it is necessary to order and structure items in a queue