Introduction
Heijunka is a tool used in lean manufacturing which focuses on eliminating waste without losing productivity through a manufacturing technique that relies on leveling production. Popularized by Toyota, lean manufacturing is often seen as an alternative and more effective manufacturing process than mass production that is commonly used in America (Friddle n.d.). Whereas mass production relies on production in large batches to obtain the lowest cost per part possible, lean production instead focuses on the flow of production, adjusting flow as demand changes. One of the primary problems heijunka serves to solve: how do you produce the correct amount of product when demand is always changing? The traditional …show more content…
For example, let's assume that the average demand is 12 units a week, which would be 2.4 units per day. The takt time would then be .41 days per unit (1 day divided by 2.4 units). If the manufacturing pace is currently set up to have .50 days per unit then the facility knows that they need to increase the pace to ensure they meet customer demand. The production pace and takt time need to be the same for heijunka to be fully implemented, in other words, level the production with demand.
Level output by product mix
Most manufacturing facilities make a wide range of products, not just one. So the last step in implementing heijunka is to level the output by product mix. Before lean manufacturing concepts emerged, the idea was to batch build that wide range of products. Under the heijunka idea, this is incorrect. The idea of heijunka is to not only level the volume of output, but also by the product mix. Assume a company is creating products A, B, C, and D. Batch building would create a production schedule like this:
AAAA BBBB CC DD A manufacturing facility, with heijunka implemented, would follow a production schedule