Lean Six Sigma methodologies help EMS teams reduce waste, improve yields and drive consistent process improvements.
The mantra of the electronics manufacturing services (EMS) industry has long been better, faster, cheaper. OEMs outsource to improve their bottom line in some way. EMS partners need to deliver that service faster and at less total cost to their customers to make financial sense. That leaves little margin for error, and in the complex world of EMS, achieving those efficiencies means the entire production team must work together to eliminate waste and inefficiencies.
Lean Six Sigma gives employees the tools and training to optimize the production process. To better understand the difference:
- Lean equals = capable (oriented to wastes)
- Six Sigma = effective (oriented to defect reduction)
- Lean Six Sigma = capable and effective.
A key element in training is to teach employees to recognize the seven wastes:
- Waste of overproducing (no immediate need for product being produced)
- Waste of waiting (idle time between operations)
- Waste of transport (product moving more than necessary)
- Waste of processing (doing more than has been agreed upon)
- Waste of inventory (excess above what was required)
- Waste of motion (any motion not necessary outside of production)
- Waste of defects (producing defects requiring rework).
It is also important to give teams a problem-solving methodology that helps them problem-solve in a structured way that tests assumptions, documents results and helps create repeatable process improvements.
At SigmaTron International, Green Belt teams have used a DMAIC (define, measure, analyze, improve, control) methodology to identify each improvement opportunity and strategize the appropriate solution.
In the Define phase, a problem statement is developed, critical to quality (CTQ) and defect metrics are identified, project objectives are created, the business case and financial impact of the desired improvement are determined, customer impact is assessed, milestones and a timeline are set, the project scope and boundaries are assigned and team responsibilities are mapped out.
In the Measure phase, the variances that a team associates with the problem they have identified are measured utilizing core tools such as cause-and-effect diagrams and gage R&R measurements. In the Analyze phase, data are analyzed to determine trends and possible corrective actions. In the Improve phase, improvements are implemented and then design of experiments (DoEs) is used to determine if the proposed solutions are correcting the problem. In the Control phase, measures are implemented to ensure continued achievement of desired metrics.
Another relevant methodology that can be useful is the Eight Disciplines (8D) problem-solving methodology, particularly as a framework for analyzing customer issues and defining the specific challenges to be solved.
The 8D methodology was originally developed by the US government during World War II. It was refined by Ford Motor Co. in the 1980s and grew in popularity.
Plan was added as discipline zero to the methodology after it was named, so technically, there are nine disciplines. They are:
- Discipline 0: Plan
- Discipline 1: Form a team
- Discipline 2: Define and describe the problem
- Discipline 3: Develop an interim containment plan
- Discipline 4: Determine, identify and verify root causes and escape points
- Discipline 5: Choose and verify permanent corrections for problem/non-conformity
- Discipline 6: Implement and validate corrective actions
- Discipline 7: Take preventive measures
- Discipline 8: Recognize the team.
Lean Six Sigma core tools are particularly important in EMS environments because of the need to continually fine-tune production aspects that are out of the EMS provider’s control. For example, EMS providers do not have control over product design. They can influence it with design for manufacturability (DfM) recommendations, but they still may have to accept a design with inherent defect opportunities. Arming a production team with the tools they need to rapidly identify defect root causes and implement appropriate corrective actions results in better yields, better schedule adherence, less rework and less scrap.
Benefits and related core tools include:
- Reduction in cycle times and cost of operations utilizing value stream mapping (VSM) and single minute exchange of die (SMED) tools
- Improved productivity through adoption of Lean principles and Kaizen events
- The ability to better meet customer expectations through voice of the customer (VOC) focus and key performance indicator (KPI) measurements.
Including Lean Six Sigma training in an overall training program can help employees develop the skills needed to identify issues and work collaboratively to resolve them.
Michael Schillaci is COO at SigmaTron International (sigmatronintl.com); This email address is being protected from spambots. You need JavaScript enabled to view it..
