Wednesday, January 15, 2014

Kanban System at a Medical Device Manufacturer

Interested in how a replenishment kanban system works?

A kanban system is a way to handle inventory using a pull system. A minimal amount of inventory is kept and material is only replenished when it's pulled from the storage location.

A two bin kanban system is the simplest form of kanban. Each part number is stored in two bins. When one bin is used up, the empty box is a signal to the previous process to produce more parts and fill the box. The second box is used while the first one is being replenished. Simple!

I posted a video last year showing a 2-bin system using a gravity flow rack.

The video below is from a medical device manufacturer showing their lean production cell. Kanban is just one part of their process and you can see how they use it to manage their component inventory. The parts are stored in a component supermarket area, where the 2 bin kanban system is demonstrated.

View the embedded video below or watch the video on Youtube:

1. Component Kanban System
Each part box is labeled with the type and quantity of parts and the location where it is stored. When the assembler runs out of parts at the work station, he brings the empty bin to the part storage area and takes a full bin back to his work station. The empty bin is a signal to replenish the storage area with more parts.

2. Lean Work Cell
Each module seems pretty complicated, but there is a unique work cell set up for each one. This allows all parts and tools to be at the assembler's fingertips. Each work station has an online step-by-step work instruction, with pictures to reduce mistakes.

3. Single Piece Flow
After assembly, each module is placed on a rack. There's only room for one of each type, so no overproduction! The team assembler moves on to the next part that the customer needs.

This video is an excellent example of a kanban system in use. If you are implementing kanban, it might be worth viewing this video, or showing it your team to get the ideas flowing. Everyone's process is different, but kanban can be tuned to fit each application.

For more videos like this, check out my huge list of training videos!


  1. Top-rated blog. This is a good example, but wont you freeze money by making kanban points of wip in between stations? Would it be better to pull directly from the first station, once finished goods are pulled by customer from FGI? thanks a lot!~ Paula Jones

    1. Thanks for the comment. I think reducing WIP makes sense if you can pull directly from the first station, but it looks like the testing procedure is either longer than takt time, or finding too many bad pieces, which is probably why they need to keep extra WIP. Not ideal, but sometimes inventory in the right place will help reduce fluctuations and smooth the work flow.
      I'm not familiar with the process, just trying to glean info from what I see in the video.