Lean is highly effective, but it’s hard to do right.

In 1949, on a factory shop floor in Koromo, Japan, an automotive company implemented a process to increase efficiency, eliminate waste and improve quality in its manufacturing. Today, this company – Toyota Motor Corp. – is a market leader because of the success of the Toyota Production System.  
A recent study conducted by Aberdeen Group showed 90% of 308 manufacturers surveyed reported a commitment to Lean. Yet less than 10% of these companies are considered Best in Class – practicing Lean manufacturing principles within and beyond the production floor.¹ Lean principles have proven highly effective in increasing value for customers, but few companies are embracing Lean because it is hard to do right.

Lean manufacturing is the continuous process of reducing muda (waste), mura (unevenness of workload) and muri (overburden of man and machine) in manufacturing operations to improve overall customer value by focusing on speed, flexibility and quality. Cross-functional teams from sites and regions are responsible for identifying and reducing muda, mura and muri to ensure continuous improvement in the supply chain and manufacturing operations.

In 2003, Solectron dedicated itself to becoming the Toyota of the EMS industry. Combining Lean manufacturing principles from Toyota with the quality rigors of Six Sigma, we created the trademarked Solectron Production System. In deploying SPS, we focused on five areas:

1. Establishing a Lean culture. For Lean manufacturing to be successful, it must be embedded in the company culture from senior management to the shop floor. Everyday, a Kaizen (continuous improvement) event takes place at one of Solectron’s global manufacturing and aftermarket services sites. Teams consisting of eight to 12 workers are formed to conduct small Kaizen events throughout the organization, yielding improvements and significant operational changes that are measurable, repeatable and duplicated throughout the company. The Functional Excellence Team (Change Management Organization), through our Kaizen Promotion Office (KPO), conducts Lean tools and applications training for all levels within the organization. A key function of KPO is to facilitate Kaizen workshops at sites, supported by Shingijutsu senseis, a world leader in Lean manufacturing, founded by members of the original Toyota Autonomous Study Group, who provide hands-on training on ways to reduce muda, mura and muri.

2. Leveraging the power of the visual factory. At Solectron, Lean manufacturing – visually seeing problems and taking corrective action (Poka Yoke, or mistake-proofing) – has reduced manufacturing rework by 75%. Seeing problems in different levels of details is a must to identify the root cause and implement appropriate actions.

Using visual cues, shop floor operators monitor performance, identify problems and take corrective action:

• Sequencing boards: A control tower for operators and management to view current status of the production floor (i.e., customer demand and material availability).
  
  
• Production Andon: Electronic displays reflect real-time performance and track productivity. The shop floor supervisor monitors shift efficiency, focusing on daily shift production goals.
  
  
• Lookout towers: Supervisors view the production floor to identify abnormalities or inefficiencies.

3. The Importance of combining Lean and Six Sigma. Lean identifies inefficiencies and defects in the manufacturing process, addressing speed, flexibility and quality while Six Sigma’s data-driven analysis delivers precision and accuracy. Each approach offers a proven set of tools, creating a powerful mechanism for reducing defects in the manufacturing process.

4. Kaizen – improving work processes. Globalization forces the entire supply chain to find ways to improve speed and flexibility at lower costs without sacrificing quality. We adopted continuous flow U-shaped production lines to help achieve this by:

• Reducing material handling: An operator completes work on a part, the part continues on to other operators until complete; eliminating the need for batches to be moved from one operator to the next and the potential for a loss of materials.
  
  
• Improving quality: By working on one part at a time, operators immediately detect problems, improving quality and saving on material costs.
  
  
• Less WIP: The U-shaped cell helps manufacturers move from a push to a pull method. Using Kanban cards, materials used for assembling a product are pulled at the point of consumption, not based on sales forecasts.
  
  
• Faster changeovers: Switching from one product to another rapidly is critical. By applying Lean principles, Solectron has reduced changeover times from over an hour to just minutes with the goal of seconds.

Lean manufacturing establishes a “supermarket” of parts, one location where materials are sized appropriately for the demand and located close to the delivery system. In charge of the supermarket is a “water spider,” a person who strides between the supermarket and the production line. Using Kanban cards generated based on pull signals (end-user consumption), the water spider “shops” for parts at the supermarket, delivering the materials to the manufacturing cell. The water spider arranges the materials in order of flow: High use parts are closer to the operator, followed by medium and low usage parts. Following this process, water spiders are able to mistake-proof (Poka Yoke) materials, and the operator uses both hands to pick up materials in a sequential manner, reducing cycle time.

5. Leaning out the supply chain. Creating a Lean culture is a continuous process. The journey is not simple; however, by committing to Lean, companies will gain tangible business benefits and cost savings.
 
References

1. “The Lean Supply Chain Report,” Aberdeen Group, September 2006.

Marty Neese is a corporate officer and executive vice president operations at Solectron Corp. (solectron.com), and responsible for global manufacturing, materials management and new product introduction.