Heijunka (Leveled Production): A Foundational TPS Approach

The term Heijunka, or levelized production, is an important Lean manufacturing practice. It standardizes production volumes and product types. Heijunka is a foundational component to the toyota production system that helps create a smoother workflow.

Instead of reacting to daily changes in customer demand, Heijunka helps companies produce steady amounts each day.

By setting a regular production schedule, companies can prevent overproduction and underusing resources. This also helps avoid sudden workload spikes that can cause inefficiency and stress for employees.

This method enables businesses to handle demand variation without overwhelming their production lines or overstretching labor. By using kanban systems to signal production needs, Heijunka makes sure that only what is needed is produced at the right time. This leads to better synchronization of production efforts.

Heijunka is not only about meeting demand consistently; it’s also about creating predictability. Companies using this method can improve their long-term planning. It helps them create a stable operational base. This base allows for more accurate forecasting and smoother workflows.

Importance of Heijunka

In Lean manufacturing, standardization is key. Heijunka helps to stabilize work flow.

This reduces the need for overtime and extra labor. It also ensures efficient use of resources, such as raw materials and components. By producing a steady daily output, companies can cut waste.

They can also improve inventory control with kanban systems. This helps reduce the chaos from changing orders.

• Minimizing Stress: One of the greatest advantages of Heijunka is the stabilization of the workforce. Employees benefit from a more predictable schedule, knowing what is expected of them daily rather than constantly adjusting to spikes in production.
• Resource Optimization: With stable production levels, raw material usage is better controlled, meaning companies are less likely to over-order, under-order, or hold excessive stock levels. This benefits overall cash flow and reduces the waste associated with surplus inventory.
• Kanban Integration: The kanban system plays a critical role in supporting Heijunka. These visual signals help produce or restock the right amount of inventory at the right time. This prevents excess stock and ensures there are enough supplies to meet daily demand.

Implementing Heijunka

To effectively implement Heijunka, firms must rely on accurate customer forecasts and historical data. These insights help set level production volumes and fluctuation stock, which act as buffers for daily demand variability. This planning ensures that we keep the appropriate amount of inventory. The process controls and directs actions, reducing waste from excess stock.

When implementing Heijunka, understanding and preparing for variability is critical. Customer demand will always change to some extent. However, Heijunka helps reduce these changes by setting a standard daily output to meet customer demands. This is achieved by:

• Forecasting: Historical data on customer demand is combined with predictive tools to forecast expected demand levels. Forecasts are not always perfect, but they help set a baseline for production volumes. This ensures the production flow can meet most orders. This typically is expressed in the form of Takt time, or pace of customer demand.
• Fluctuation Stock: Inventory levels must accommodate the natural fluctuations in customer orders. By keeping a steady amount of stock, businesses can meet daily demand changes. This way, they do not have to change production rates or schedules often.
• Balancing Efficiency with Flexibility: One challenge companies may face in implementing Heijunka is balancing level production with flexibility. For example, even when customer demand exceeds production levels, fluctuation stock allows businesses to continue meeting orders without overextending the manufacturing process in operations.

Benefits of Heijunka

The primary benefits of implementing Heijunka are stabilization and predictability. Production schedules become more consistent, reducing stress for the workforce and improving morale.  As a key Lean leader, you will be able to observe problems much easier due to the stable nature of the process.

Manpower remains steady, and the team avoids unnecessary overtime, which contributes to operational efficiency. Additionally, controlled inventory and optimized raw material use reduce waste, resulting in cost savings.

With level production, businesses can anticipate their needs with greater accuracy. This leads to a number of operational advantages, including:

• Cost Efficiency: By reducing waste in the form of overproduction, excessive inventory, and inefficient labor usage, companies can save significantly on operating costs. Heijunka allows businesses to focus their efforts on producing the right quantity and the right type of product, at the right time. This typically reduces inventory overall for the production process.
• Improved Quality Control: Levelized production helps to maintain higher standards of quality, as workflows are streamlined and employees have a consistent workload. This minimizes the likelihood of errors and ensures that manufacturers produce products consistently to meet customer expectations.
• Employee Morale and Engagement: One major outcome of Heijunka is the positive effect on workforce morale. Employees feel less stressed because their tasks and workloads are predictable. This predictability helps them stay more engaged and productive. Stable, manageable workloads also contribute to a healthier work-life balance.

Overcoming Challenges

While Heijunka offers significant advantages, it’s important to note that some team members may resist the transition. Patience and clear communication about the long-term benefits can help ease the change. This ensures that the whole team supports the smoother and more efficient workflow that Heijunka offers.

Resistance to change is a common challenge, particularly when new systems or processes disrupt established routines. Overcoming this requires strong leadership, transparent communication, and demonstrating the long-term benefits of Heijunka. By keeping the team informed and involved throughout the process, companies can build momentum for continuous improvement.

For more information on Lean Consulting and how to implement Heijunka in your organization, visit our Lean Consulting Services.