All product quality issues can be traced to problems within processes. Material handling processes, in particular, can make or break a company's quality initiatives.
Years ago, American quality was nothing to brag about. Color televisions were so unreliable you could buy insurance contracts to repair them. In fact, that was the predecessor of the modern-day service contract. Those days, almost every automobile dripped oil, while mechanics explained, “They all leak; they are designed that way.”
The implications of quality related to consumer products seem obvious, but how can quality impact other areas of the business, such as material handling? For that matter, what does quality have to do with material handling, anyway?
Some aspects of material handling clearly relate to quality, such as avoiding product damage, but quality goes well beyond that obvious example. It extends to all aspects of the business process. A process is simply a sequence of activities by which our work is accomplished. We can think of quality as the degree to which a process does what it is supposed to do (or not do).
Process Quality Defined
In broad terms, a material handling process must deliver [ultimately to the customer] the right item, packaged as required, undamaged, at the right time, properly labeled and documented. Easy to say, but not always easy to do!
Why is this important? First: for customer satisfaction and loss prevention. If we fail to deliver as expected, we will have dissatisfied customers. We will often have to spend money to make it right and may also risk loss of future business. Even if we find the problem before it reaches the customer, there is still cost involved to correct the problem.
Second: to minimize cost and maximize profitability. Quality problems are simply instances in which processes do not work as required. In fact, everything that goes wrong in a process can be considered to be a quality problem. Here are some examples of problems that might not seem at first glance to be obvious quality issues:
A trailer is loaded and ready to go, but the bill of lading is not yet ready;
While planning shipment of customer orders, some ship-to addresses are missing;
When attempting to retrieve a product from an inventory location, the wrong product is there, and no one has a clue as to the location of the right product;
After loading a trailer, an “extra” load is discovered on the dock, while records show the product as already loaded.
There might be some debate as to whether these are quality problems, since they are not product quality issues per se, but rather process quality issues. But, all product quality issues ultimately are caused by process quality issues. All process quality issues are detrimental to business.
Consider what would happen in your business if any of these four problems occurred. Usually, someone would have to take some immediate action to correct the problem, diverting them from their usual work.
Sometimes, the problem is ignored, creating a bigger problem later. If the “extra” load problem was ignored, and the trailer was shipped missing that load, the customer might complain, prompting extra shipping cost or payment delay because the order was not complete. Ultimately, the consequences of all process quality issues have negative financial impacts, either from reduced productivity, increased overhead, delays, or even lost business.
The following principles apply to quality of any sort, and we will focus on applying them specifically to improve material handling processes:
Establish a clear understanding of output requirements for the overall process as well as each step in the process.
Focus on prevention of problems, not correction. Prevention is much less costly.
Ensure that each process step guarantees that its output is correct and complete; mistake-proof where feasible.
To apply these principles, we need to understand our process, which starts with a process map — a sequenced list of actions performed to accomplish the work. This is often done graphically, as shown in Figure 1, but it can also be done with a simple list.
For purposes of our discussion, we will consider a generic process common to many businesses — storing product. This is only a starting point. In actual practice, we may need to take a closer look and explode some steps into greater detail, but this will suffice for our discussion.
Beginning with overall output requirements for storing product, the process goes like this:
All cartons are palletized in a prescribed, stable pattern;
Loads are wrapped securely according to packaging specifications;
Loads are clearly labeled in defined locations with prescribed content;
Cartons, loads, wrapping and labels are free from damage;
Loads physically reside in the same locations logged in inventory records;
Inventory count exactly matches physical inventory.
These requirements, along with supporting documents (such as packaging specifications), define what the process must produce. Knowing these requirements, we could inspect the process output to confirm that it is operating correctly.
While inspection has been used for many years as a primary means to ensure quality, it should not be relied upon as the only way. Inspection can detect gross problems or high-frequency problems but is not effective or efficient at detecting infrequent, subtle problems. For example, inspection could easily detect a badly damaged load but might overlook a slightly smeared barcode label. Moreover, anything detected by inspection has already occurred and will cost money to correct. Remember that our focus needs to be on prevention rather than correction. If we prevent problems from occurring in the first place, we never need to inspect for them and never have to worry about what slipped past the inspection process.
We need clear requirements for each step to guarantee that each step produces only good output (correct and complete). There are a variety of ways to establish those requirements, but a good starting point is with overall process output requirements. If we examine each requirement and consider the potential impact that each process step has on that requirement, we can identify those steps that contribute to achieving each requirement.
This can be conveniently summarized graphically in a process planning chart, using “Os” to identify links between process step and overall output requirements (Figure 2).
We can see at a glance that, if we wish to guarantee there is no damage, then we need to address five process steps (1 through 4 and 6), while two steps do not contribute to damage.
Next, we look more closely at each of the contributing process steps and identify specifically how that step contributes to the requirement. Sometimes, it is easier to identify how that step can fail to meet the requirement. For step 1 (Receive Cartons), failure conditions might include:
Cartons damaged upon receipt;
Cartons missing label or incorrectly labeled;
Cartons in wrong orientation (will jam in palletizing equipment).
The first two items may not be within our direct control but are often within our influence. Just as we seek to ensure that the outputs of our processes are correct, we have the right to insist that what we receive is correct. What we receive is, in fact, the output of a previous process. If we can convince the owners of that previous process to eliminate those failures, then both their process and ours will be improved.
Still, it may be wise to use technology to detect any problems that do get through, especially if we are not convinced that the problem is actually solved. A barcode reader that attempts to read the carton label could signal that a label is missing, unreadable or in the wrong position, for example. However, high-cost or high-complexity approaches, such as sophisticated vision systems, should be avoided.
Sometimes, there are political reasons we cannot influence the previous process. If the previous process occurs at our customer's location or in a more “important” part of the company, there might not be much willingness to improve that process. It would be best to give it a try, but if you are unsuccessful, then you may need to adapt your own process to correct or eliminate the problems. But don't give in too easily, as this increases cost in your process!
The last failure, carton orientation, might be better addressed in your process. Technically, it may be very difficult to ensure proper orientation of a carton transported to you through multiple conveyors, but it's relatively easy to install a simple alignment mechanism to remedy the problem.
We can boil this down into three rules:
If you control what causes the failure condition, control it.
If you don't control it, find out who does and try to get them to fix it.
If you can't convince the other party to correct the problem, you may have to correct it yourself.
Obviously, the third choice is least desirable, but it may be better to correct the problem rather than letting it go. If we allow a damaged carton through the system, we may end up with a palletizer jam, unstable load, or at least a customer complaint!
This approach of identifying how each process step contributes to overall requirements, then identifying failures and determining how to prevent them, is repeated for all of the identified process steps. By applying this approach to every known failure to meet requirements, you will eventually eliminate them from your operation.
Clues of Variability
Don't miss the opportunity to visually review each step of your process, looking for clues that it is not working properly. Look for things that are clearly wrong as well as things that are different but should not be.
Things that are different, such as unplanned differences in label locations or visible differences in pallet wrap patterns, are indicators of process variability. This variability is a powerful signal that the process is not working as it should, inviting you to take a closer look to understand what is happening.
To further bullet proof your processes, consider potential failures — those that might occur but have not yet. We can often identify many more potential failures than actually occur, which seems like an impossible task! We don't have to eliminate all of them, but we can prioritize the list (based on severity or likelihood) and then attack the ones that matter most. Consider actual conditions in the workplace; a low-severity problem when handling paper products may be a high-severity problem when handling hazardous materials.
Once the necessary process improvements have been made, we need to confirm that the improvements are effective on an ongoing basis. This is done with process audits — systematic reviews that confirm output requirements are being met and that the process is working as intended. If your business is ISO 9000 registered, you may be familiar with this audit process. However, don't rest on your laurels if you are ISO 9000 registered. If you are still having problems, you may not have identified all of the important issues. If this is the case, simply apply the improvement process as described, and adjust your ISO 9000 documentation accordingly.
All of this may seem like an enormous amount of work, but imagine how much better things can be when just about everything that could go wrong simply can't happen! If we can focus on getting the work done instead of “fire fighting” problems, we can all go home at the end of the day with a lot less stress and a lot more accomplished.
William (Bill) Eureka is president of consulting firm EurekaResults.com, headquartered in Lowell, Mich. He has more than 40 years of experience in engineering, manufacturing and consulting with more than 400 companies. He is a Six Sigma Master Black Belt, Jonah (Goldratt Institute, Theory of Constraints) and Lean Master, with more than 60 kaizen events completed. Learn more at www.eurekaresults.com.
Quality: The Heart of Lean Material Handling
The basic measures of a lean strategy are quality, cost and delivery, says Tony Manos, chair of the Lean Enterprise division of the American Society for Quality (ASQ) and process improvement consultant at Profero Inc. “You need a balance of all three.”
Manos suggests companies focus on quality at the source — in other words, don't put a bad product on the shelf. To ensure quality at the point of sale, material handling professionals must develop controls and techniques for eliminating wasteful tasks.
“Product recalls reflect a company's focus on delivery over quality,” he says. “When production rates are beat into employees' heads, there is more pressure to let things go. But you don't necessarily need 800 parts an hour; you need 800 good parts.” After all, he adds, bad parts require rework, which means more waste and cost.
For processes that require testing, Manos recommends finding a quicker way to conduct tests (such as doing them just in time) and building a system that won't allow product out the door until it's been tested. “Lean is not about working harder,” he says, “it's about focusing on value-added tasks like testing and getting rid of wasted effort.
“5S, often underestimated, is fundamental to a lean supply chain,” Manos adds. “Cleaning is only one portion of 5S. It also includes inspection. While cleaning, employees should be looking for things that are not normal, and if they find them, it should lead to an investigation.”
Quality can also be built directly into processes, says John Glahn, senior field engineer at the Mid-America Manufacturing Technology Center (MAMTC). “3-D measurement technologies, for example, can check quality as a process is running,” he says. “This allows an operation to catch problems faster and stop the line to correct them before it produces reject parts.”
Over the years, ISO requirements have become more process based, Glahn says. “The six written procedures required include control of documents (quality procedures), control of records (quality testing and verification), control of non-conforming product, internal auditing, corrective action procedures and preventive action procedures.”
One thing that hasn't changed, however, is the need for support from the top. “Quality improvements require top-management commitment,” explains Glahn. More than ever, quality is a distinct marketplace advantage, and that can help managers attain the executive-level support they need. “ISO 9001 expands a company's ability to bid on more opportunities and grow its business,” Glahn says.