GETTING LEAN

Lean Six Sigma and Agility

How to identify opportunities for improvement and enable corrections before the product is at risk.

The electronics manufacturing community is facing unprecedented challenges in 2021. Component supply and product demand are completely out of sync in many industries. Material constraints and transportation shortages are stretching lead-times even on committed orders. An economy flush with stimulus money and pent-up demand for products not available during much of 2020 has eliminated the ability of original equipment manufacturers (OEMs) to plan based on historical trends. In the middle is the EMS provider that sees material arriving later than planned, while at the same time experiencing unplanned increases in order volumes on many programs. Lean Six Sigma provides production teams the tools they need to identify issues, analyze potential improvements and implement changes that help keep production flowing on time even with changing production inputs.

SigmaTron International’s Tijuana, Mexico, facility utilizes teams of Lean Six Sigma Green and Yellow Belts in its continuous improvement activities. They use a variety of core tools in that process.

One tool is the Gemba Walk. The term Gemba comes from the Japanese word for “the real place.” Taichi Ohno, a Toyota engineer and leader, is often credited with developing the concept of the Gemba Walk or the idea that leaders should regularly and frequently be present to observe the work of their organization when and where it takes place.

In a Gemba Walk, leaders visit the work area to glean first-hand knowledge regarding:

  • How products are built
  • How services are provided
  • Current challenges
  • Opportunities for improvement.

One of the benefits of Gemba is its role in identifying opportunities for improvement, enabling corrections of any potential issue before they represent a risk for the product. This interaction also enables leaders to learn more about each operator’s experiences and knowledge over the process. Gemba and a 5S work environment are fundamental to sustain any Lean Six Sigma project.

At SigmaTron, weekly Gemba Walks involve a multidisciplinary group. Findings and opportunities are posted on a central key performance indicator (KPI) board. A Gemba Walk earlier this year identified the potential for improvement in a project experiencing significant volume increases.

A Lean Six Sigma team utilized the DMAIC (define, measure, analyze, improve, control) methodology to analyze the project and set improvement goals. In the define phase the key goals identified included improving throughput and operator productivity.

The team utilized the SIPOC (suppliers, inputs, process, outputs, customers) diagram during the define phase to create a high-level process map of all inputs and outputs, similar to mapping done in value stream analysis. They mapped the process and then created a current state production layout. This exercise did two things: First, it ensured a high-level understanding of the scope of the production process they were evaluating; second, it helped them identify process elements that could be improved. Time studies were performed on specific production steps to determine areas of line imbalance. A steady-state production layout was created that reflected an improved, better balanced production layout. In the current state layout, printed circuit board assembly (PCBA) arrays were separated into individual pieces prior to conformal coating inspection. In the steady-state layout, arrays were inspected prior to depaneling. As part of the DMAIC control phase, electronic pacemakers were added to track units completed by hour to ensure production operators were aware of output vs. goal on an hour-by-hour basis.

Takt time, or the average time interval between the start of production of one unit and the start of production of the next unit, was cut by more than half in the steady-state process, improving throughput and operator productivity. The entire project took less than a week.

Examples such as this illustrate the combined benefits of the Gemba process when coupled with well-trained teams and core tools. To further enhance this process, a Lean Six Sigma database has been created that enables teams to review past projects and results in a dashboard format. Lean Six Sigma tools are beneficial in their ability to drive continuing operational improvement even in times when supply and demand are well aligned. In the current environment, where material constraints and transportation issues can lengthen the cycle time associated with material arrival and product shipment, they offer a way to shorten the actual time it takes to manufacture the product, helping manufacturing teams stay agile in the one variable they can control.

Filemon Sagrero headshot

Filemon Sagrero

is the continuous improvement engineer at SigmaTron International in Tijuana, Mexico; filemon.sagrero@sigmatronintl.com.