The closed-loop approach to quality reduces cycle times and other key manufacturing metrics and also provides the top-line benefits that product quality drives. Karim Lokas, Camstar Systems, Inc.
Leading-edge industries such as solar (i.e., photovoltaic or PV) and semiconductor manufacturing have made a concerted effort to shorten cycle times to improve process and production efficiencies as a means to gain competitive advantage. Many tools have been proposed for reducing cycle times: automation, six sigma, lean manufacturing, and better synchronization between demand and supply. Product quality permeates all these tools. Product quality or the lack of it has a direct and significant impact on total cycle times and lead times. It’s time that manufacturers make that connection. In this article, we discuss a closed-loop approach to quality that enables cycle-time reduction.
Karim Lokas, Camstar Systems, Inc., Charlotte, NC USA
Peter Drucker, one of the strongest advocates for and most subtle analysts of business and industry, gave this advice: “Until we can manage time, we can manage nothing else.” A close look at the development of manufacturing might compel one to add a rejoinder to Drucker’s statement: unless we look closely at product quality, we’ll never manage time effectively; certainly, we’ll struggle to shorten critical cycle times. In fact, shorter cycle times are typically a natural outcome of a good, closed-loop process. In emerging and highly competitive industries, rapid delivery of top quality products can mean the difference between survival and success.
The solar perspective: why cycle times matter
The solar industry is a good example of why cycle times are important, and how cutting cycle times can speed the achievement of industry goals. This industry wants to be a viable alternative to fossil fuels, which is only achievable through grid parity— that is, the leveled cost of electricity (LCOE) delivered to the consumer has to be equal to the total cost of the current mainline energy grid. For this to happen, fundamental shifts must occur in the manufacture of solar products and in the cost of installation and maintenance of solar energy systems.
A key question is, what is the role of the solar or PV manufacturer in this complex chain that is ultimately intended to support a grid equivalent cost per kWh? Roughly 80% of a solar energy system’s total cost comes from manufacturing its products. For solar or PV manufacturers to play their part in changing the dynamics of the market—and the economics of the market—they have to look at their manufacturing processes and understand how cycle time is a key factor in lowering costs and speeding responsiveness to market demand.
Total cycle time (TCT) is the period from when a demand signal is communicated to a manufacturer to when finished goods are available for distribution logistics. Therefore, TCT has a huge impact on lead time: the time from when a manufacturer makes a promise of shipment or a sales order commitment to when the product arrives at the buyer’s destination.
Obviously, cycle time is central to manufacturing costs. The more distended and inefficient the cycle, the greater the costs will be. Long manufacturing cycle times are expensive. They result in lower customer satisfaction, higher costs of carrying excess WIP and inventory, increased operating overhead, and poor asset utilization. This is why manufacturers are working so hard to cut their cycle times.
How product quality affects cycle time
How does product quality play into cycle time? Simply put, the more time a manufacturer spends making good product is time that is not spent making bad product. That focus cuts cycle times more effectively than just about anything.
Conversely, the time you’re making bad product or less-than-perfect product is inversely related to both the amount of product you can make and the time it takes to make good product, on average, from all the wasted time, rework, or energy that goes into dealing with bad product. It’s time that is adding up and being averaged out across cycle times for all your products. The way to start reducing long cycle times is to eliminate quality problems at their source in the manufacturing process.
Figure 1. Closed-loop model for advancing product quality.
A closed-loop approach (Fig. 1) to product quality can identify and remove the causes of process variability that result in low yields, product performance issues, long troubleshooting, and, specifically for PV manufacturers, the inability to reduce cost per watt for their customers. This closed-loop approach unifies collaborative design, planning, supply, manufacturing, and customer experience through an enterprise quality process that accelerates continuous improvement and innovation while removing the causes of long cycle times.
The first step is manufacturing enforcement. Solar and semiconductor manufacturers can dramatically reduce cycle time, waste, and yield loss from poor quality through ‘Right First Time’ enforcement.
Enforcement in manufacturing applies to the “five Ms”:
• Man: Only trained certified operators perform the work.
• Materials: Use the right materials, at the right revision, at the right step for the product.
• Method: Every procedure in the process is performed correctly, in the right sequence.
• Machine: Use only properly maintained and calibrated equipment or tools.
• Measure: Tests must be performed, and the results must be satisfactory, before processing can continue.
The process is also audited and quality characteristic data collected to analyze the as-manufactured record for improvement opportunities. The goal is to gain global visibility into quality to uncover trends and relationships driving non-conformances, and to systematically alert operations to these trends.
These enforcements will not work with a reactive approach. You can’t say, ‘I want to reduce cycle time and let me start patching up the system. Every time there’s a leak I go chase a leak.’ If you do this, you end up with a patchwork solution that adds its own inefficiencies while attempting to solve part of the problem.
Once enforcement is in place, it is important to focus on understanding the ebb and flow of the process, or process understanding and planning. This is especially relevant in the solar and semiconductor industries, where there is a greater need for understanding of the process and its variables, and what variables affect the outcome of the process (Fig. 2).
Figure 2. Engineering can immediately see the effectiveness of a corrective action intended to resolve a pervasive issue. This analysis chart instantly exposes an issue with the new raw material revision that can be addressed before more units are produced.
In this planning stage, process plans are developed concurrently with product design to optimize manufacturing ramp-up. Manufacturing and supply processes are improved by leveraging past and current process capabilities, as well as capacity performance (Fig. 3). Seamless engineering change processes are instituted to speed implementation and reduce errors.
|Figure 3. Solar and other high-tech companies using APQ receive the benefits of shrinking the learning curve needed to achieve full scale production, and consequently shorten production cycles.|
The manufacturer not only prevents poor quality at the source, but gains greater understanding of process capabilities. If a process is not yielding at high levels and there are ways to improve the design of the process or the product, one can reduce the losses in the system and improve the throughput of the manufacturing process and cut cycle times—through this process of planning and understanding that goes beyond enforcement.
The third element absolutely relevant to cutting cycle times is continually improving product quality and process capability, not only by understanding how one’s processes are operating, but also how the product is performing in the field. Manufacturers can achieve rapid identification and removal of root causes by leveraging a growing knowledge base of product design, process design, manufacturing (as-built and inspection), and aftermarket and quality event data. Through this greater understanding, you can pour knowledge back into your product design and process design so that you’re inherently producing higher quality, higher volume product on a consistent basis, not just capturing the potential points of leakage.
Cases in point
Application of the closed-loop approach to product quality has been effective for major players in the solar and semiconductor industries. Albuquerque, N.M.-based EMCORE Corporation offers a broad portfolio of compound semiconductor-based products for the broadband, fiber optic, satellite, and solar power markets. The company’s photovoltaic segment provides products for both satellite and terrestrial applications. For satellite applications, it offers high-efficiency gallium arsenide (GaAs) solar cells, covered interconnect cells (CICs), and panels. For terrestrial applications, EMCORE is adapting its high-efficiency GaAs solar cells for use in solar concentrator systems.
Faced with manufacturing challenges including rapid growth, demand for innovative technologies, and the need to reduce product cost per watt, EMCORE adopted Camstar’s closed-loop quality approach that resulted in:
• 3x growth in 4 years;
• 22% reduction in cost per watt;
• Increased cell efficiency:
• Terrestrial increased up to 38%;
• Satellite increased up to 32%; and
• Faster root-cause analysis of quality problems.
Cross-industry benchmarks from companies in various stages of deploying our closed-loop quality approach show outstanding results that contribute to shorter cycle times:
• 35% more throughput, 80% fewer nonconformances— while reducing lot sizes;
• Elimination of 6,000 hours per year in paperwork— and virtually all operator errors;
• 25% increase in shipments— and fewer returns; and
• Increased factory operation to full capacity while reducing the rate and severity of end-product quality issues.
The beauty of the closed-loop approach to quality is not only reduced cycle times and other key manufacturing metrics, but also the top-line benefits that product quality drives. These include reduction of overall operating costs, greater customer loyalty, and protection and augmenting of brand value. Ultimately, this allows manufacturers to gain market share in their current sphere of competition and capture new markets.
Karim Lokas received his Bachelors degree in electrical engineering from New Jersey Institute of Technology and his Masters degree in bio-medical engineering jointly from New Jersey Institute of Technology and Kessler Institute. He is VP of product strategy at Camstar Systems, Inc., 13024 Ballantyne Corporate Place Suite 300, Charlotte, NC 28277 USA; ph.: 704-227-6641; email [email protected].