Heijunka Box

Heijunka is considered as a very important management concept that is created by Toyota Motors. It refers to the smoothing of the production for the purpose of eliminating stress in the system being caused by the spikes and drops in production. This also enables the company to apportion the resources evenly all throughout the year and it also put less stress on people and on machinery as well. Production takes place within small batches in order for the fluctuations to be easily controlled.

What is Heijunka Box?

There are also indeed tools that should be used in order for Heijunka to be successful. And one vital tool used in Heijunka would be the Heijunka box or also called as levelling box. It is referred as visual scheduling tool being used in Heijunka and is the name of the specific tool used in order to achieve the goals of Heijunka. It is generally a wall schedule that is divided to a grid of boxes or a set of the pigeon-holes or rectangular receptacles.

Every column of the boxes represents a specific period of time and lines are drawn down the grid or schedule or grid in order to visually break the schedule to columns of the individual shifts or the days or weeks. Colored cards represent individual jobs which are referred as the Kanban cards and are placed into the heijunka box in order to provide visual representation of those upcoming production runs.

This heijunka box makes it easy to see the types of jobs are being queued for production and when they are being scheduled. Workers on the process remove the Kanban cards as for the current period from the box as for the purpose of knowing what to do. The said cards would be passed to another section once they process the said related job.

How about the implementation?

This Heijunka box allows easy as well as visual control of the smoothed production schedule. A common heijunka box would have horizontal rows for every product. It has vertical columns for the identical time intervals of production. Production control Kanban are being placed into the pigeon-holes being provided by the box in proportion to the number of items that should be built of a given type of product during the time interval.

To make it a lot simpler, the cards are being fitted in every slot according to the work plan for the certain period. These cards would be colored based on the code. Workers arrive and make their way to the said Heijunka box wherein they draw the cards for a certain period. This enables them to do their job based on the plan therefore making sure that the work would be completed within correct manner.

The said management concept can definitely be useful in the manufacturing industry because it eliminates the stress due to drastic fluctuations into the production through the year. Companies that would use the said concept not need to pay overtime to those employees within certain times of the year.

— Slimane Zouggari