Cutting time-to-market and shipping errors using Lean principles.
OEMs “new to outsourcing” represent a special challenge for electronics manufacturing services providers because often their systems and processes are not as defined and documented as those of companies that regularly work with EMS partners. Nevertheless, such OEMs also represent the segment of EMS customers able to leverage the most value from a successful outsourcing partnership, provided the EMS company properly sets expectations. Lean manufacturing philosophy’s focus on process improvement and elimination of non-valued-added activity provides an excellent roadmap in this expectation-setting process.
The seven wastes provide ample guidelines for areas of improvement in transitioning new-to-outsourcing projects:
Simple fixes are often the best solution for small variances.
In a perfect world, manufacturing process setup should eliminate the potential for mistakes. In practice, however, process complexity and the impact of system variation makes that impossible. Consequently, organizations committed to the efficiencies of Lean manufacturing often use a range of tools to identify and eliminate defect opportunities from their process.
SigmaTron International’s Tijuana, Mexico, facility uses a number of these tools in this process. During project launch, advanced product quality planning (APQP) failure mode and effects analysis (FMEA) is used to set up the most efficient, defect-free process. The product part approval process (PPAP) is used on automotive projects to validate the process, while customer-specific validation processes are used for projects in other industries. Once production is ongoing, statistical process control (SPC) and other forms of quality data collection and monitoring are utilized to monitor processes and track defects. When defects occur, a kaizen event is scheduled, and tools such as 8D problem-solving, Six Sigma’s Define-Measure-Analyze-Improve-Control (DMAIC) and poka yoke are applied to analyze and correct the root cause.
Ten steps for achieving good design for excellence.
Eliminate variation that causes inefficiency or defects, while maintaining flexibility to scale.
A configure-to-order assembly process helps reduce finished goods inventory and enhance scheduling flexibility. However, it also introduces variation in the production process. Use of Lean manufacturing principles in designing production flow can ensure efficiency and minimize the defect opportunities this level of variation could otherwise create.
SigmaTron International’s facility in Acuna, Mexico, has a dedicated assembly and test “focused factory” area to provide configure-to-order (CTO) services for a manufacturer of industrial products. The customer has outsourced over 50 different product types that are a mix of legacy and current product.
Design for manufacturability (DfM) analysis is performed during the new product introduction (NPI) phase to identify potential issues prior to the product entering production. Test strategy and programming development is conducted for new products, and test programming is optimized for legacy products, where needed.
But don’t obsess over the distribution.
Yes, I said it. Normal data are nearly never normal.
In Six Sigma classes we study outliers, shift, drift and special cause events. But what we don’t always consider is that these “unexpected” data points may be part of the process and not as rare as we think.
First, let’s look at a set of screw torque data. The chart in FIGURE 1 is for a set of screw torques taken sequentially from a “smart” driver. We can see the data are normal (p=0.895), and the histogram and time series plot back that up.
There are times increasing inventories and AVLs makes sense.
A constrained supply chain represents a challenge to Lean manufacturing processes, but in the electronics manufacturing services (EMS) market, the bigger challenge is often OEM misperceptions about strategies to address this. From a Lean perspective, navigating a constrained supply chain often requires taking one step back to move two steps forward.
Our November 2017 column discussed several areas where the best strategy was “at odds” with Lean manufacturing principles, including: