How to use statistical process controls
With customer satisfaction as a primary business goal, products and services must continue to improve the price-value relationship. As bakers, food manufacturers and suppliers, we must be dedicated to continuously improving through established and proven process control methods.
Before process control systems can be practically implemented, management must have a clear direction. Fundamentally, management must be committed, though this can be difficult in today’s business climate. The commitment leads to accountability; accountability leads to employee education and skills development. Designated leader(s) with teaching skills and process understanding can help in the next step of discovery.
Process control is managing inherent variations in every process. Every process—baking included—has its own natural process variation, just as each of us has a specific variation in height and weight.
Process control is invaluable in managing this variation to enhance the effectiveness of the manufacturer. It is this process variation that must be controlled, not the products we produce. What must be visible are the process characteristics, not simply the product characteristics. This is where many companies waste time, money and effort trying to accomplish process control with little success.
Many bakeries and other food manufacturing facilities have great detection systems in place to practically eliminate their unusable products. But detection systems can be deceiving as they are tools and not solutions. The resulting crippling costs can bury a plant trying to make improvements. A more effective way to improve quality and lower waste is not to produce unusable product in the first place.
Proper measurement systems prevent unusable products from being made and greatly minimize the cost of waste related to a detection system. One example involves scaling weights. It was noticed in a bakery, at the initial startup of process control, that although scaling weights were being charted, one of four shift operators had a consistently higher scaling difference or variance than others. The divider extruder valves were delivering much different weights, and they had to be monitored through process charting. This discovery led the bakery to lower weight variations, which automatically led to more consistent product quality and an overall decrease in divider weight, which saved tens of thousands of dollars per year.
Another example included a bakery that was able to minimize bakery variations by intentionally converting bakery settings to be consistent across all products. At first, this seemed to be impossible. But a quality issue led to keeping sponge, dough and proofer temperatures consistent. This change did require some minor formula and setting changes, but they were nothing more than changes that normally occur in the bakery process. The bakery was able to make these settings available and visible to the responsible parties to manage and control according to process control rules.
Stability, visibility, empowerment
Using process control as more parts of the manufacturing process become stable makes unstable parts of the process more apparent. The circle of improvement through process control continues, and this excites leaders as well as the staff.
One of the basic tenants of continuous improvement is visibility. Visibility is defined as a process being monitored according to charting rules that watch for any discrepancies in the normal variation of manufacturing. When a process is visible on a chart, it gives operators a tool to improve job performance by making adjustments only when necessary. Training can be minimal and done in-house.
Many employees want to be trained just-in-time, so they know “just enough” to do their job correctly and more easily. Through charting, employees become empowered and encouraged because they learn how to better control things and see improvements in the areas they impact. Buy-in usually happens at this point, when things become visible. If employees receive incentives that relate to the efficiency of the plant, it encourages them even more when incentives begin to increase.
The more we know about our systems the better process controllers and manufacturers we become. By managing the variations in our systems, we can prevent inconsistent and poor-quality products, while making more efficient manufacturing lines. As customers demand improved product quality and consistency, process control can lead manufacturers to more educated decisions to improve processes and make more money, all the while avoiding insurmountable costs. SF&WB
Todd Bruinsma is the director at Tennessee Bun Co., LLC, Nashville,Tenn., focusing on business design and development. Bruinsma has served as general manager, a product manager and a customer service manager at Pacific Northwest Baking Co., and a quality assurance manager at Pacific Northwest Baking Co.