After value streams have been solidified and embedded, Heijunka is a crucial process implementation in every successful lean organization. Heijunka quickly and elegantly helps organizations meet demands while reducing waste. By definition, it means ‘leveling’ and enables production to efficiently meet customer demands while avoiding batching and results in minimum inventories, capital costs, manpower, and production lead time through the whole value stream. It truly is the key to stability.
Since the beginning of mass production, the technique of batching has been used to produce large lots of products, typically, without taking into consideration the demands of the customer. Output not purchased by the customer, is then placed into inventory for future use. This results in uneven product quality, overworked equipment and personnel, thus creating waste. Ultimately, manufacturers experience confusion and disorder because customer buying patterns are never consistent. In addition, when goods are placed into inventory, profitability is adversely impacted.
Heijunka helps organizations avoid these types of waste and inefficiencies, bringing production closer in line with customer demand. That type of flexibility in production allows organizations predictability and stability, thus experiencing better average production volume over the long term. By adjusting production to mirror customer demand as closely as possible, waste and inefficiencies can significantly be reduced. When organizations make all product types and maintains a small inventory buffer throughout a year, there is greater flexibility to meet changing customer demand patterns. The buffer inventory will be liquidated during the year and production will be able to meet periods of peak demand and erratic customer purchasing.
It is understood that manufacturers exist to meet customer demands, with the highest possible quality product and maximizing profitability in operations. Understanding that customer buying patterns vary, Heijunka can closer mirror those needs to efficient production. This allows fulfillment of customer needs and significant reduction of waste in the manufacturing process.