These days, with six-sigma, zero ppm, loss function, lean and many other programs, it is easy to overlook the basics. We have many different processes, systems and computers. Where is the knowledge that is contained in our daily deluge of information? Whose desk is not drowning in sea of paper? And yet, when a problem occurs, we ask for data that describes the problem and are met with blank stares.
To help sift the knowledge from your daily overload of information, try the 5W-2H method. Asking who, what, when, where, why, how and how many will help you to hear the voice of your process.
Who? Who is involved? This is not for placing blame. This is critical information needed to determine the scope of the problem and to plan effective containment. Who is it? A single operator or cell? An entire shift? A vendor? Just one OEM customer or several? The first entry on your problem-solving journey should answer "who." That way, you'll know who can give you key information, who is affected and the breadth of your problem.
What? Formulating the description of "What is the problem?" is the most important step in my experience. We all bring different knowledge, experience, education, skills and communication abilities to the table when confronted with a problem. A clearly described problem will facilitate solving it by eliminating false trails and confusion.
Make certain that everyone understands the terminology being used. Words are powerful tools. You wouldn't use a micrometer as a clamp, so don't use words carelessly, and you will find problem-solving to be rewarding. Make two columns: "Is" and "Is Not." This will reduce your time to get to an accurate description of the problem. In other words, write it down.
When? When was the problem first noticed? Before or after which operation? When was the change made? When was the last in-control reading recorded? Control charts and process logs are essential sources of reliable "when" information. If your organization has lost its discipline in maintaining process control charts and logging or tracking changes, your problem-solving will be frequent and ineffectual.
After obtaining copies of the process charts and logs, transcribe the changes and events into a
separate timeline. When posted to the timeline, machine stock-up information and derived data (such as scrap rates or tool changes) can be powerful indicators.
Where? "Where" is applicable at several levels in the process of identifying and understanding the scope of the problem. Where was the problem discovered? Where else is it found? At a vendor's, subcontractor's, toll processor's or your customer's
Where is the undesired characteristic found on the product? Where was the last operation that the parts did not exhibit that characteristic? Your process experts can ask several more "where" questions pertaining to your problem. This is also a great place to use digital photographs to show the problem and its location on the product or in the process.
Why? Isn't this what we are really trying to find out? Why did this happen? The key to successfully using "why" in problem-solving is to ask, "Why would this feature be here like this?" List the potential contributing factors that answer the question. Ultimately, what we will tell our customers and what we will do to permanently eliminate the root cause of the problem must pass the test of "why."
How? You might not know how the problem happened yet, but how it could or could not have happened are also important. You should list these possibilities before doing the legwork of the investigation. One of the best ways to decipher "how" is to imagine yourself as the part or product and then, from that point of view, explain how you got that dimple, no stamp, or no cross-hole or other imperfection.
How many? To my mind, this is the most crucial question to ask. It is also the most useful data to collect and analyze. How many contain this unexpected feature and how many are without it? How many are produced per stock-up, per shift, per day and per week? How many are in process and how many are with a vendor (such as a heat-treater or plater)? How many are at a customer's plant and how many are en route? How many were shipped by your customer to end-users?
Without knowing how many, you are in no position to even minimize disruption to your customer, let alone start problem solving. Someone needs to know the exact answers to "how many?" and "where are they?"
There is plenty of information in our world today. Our desks, computers, newspapers and televisions are filled with information. Our job is to sort the process' voice from the overwhelming noise of our daily lives. The 5W-2H method will help you tune into the voice of your process. It will help you gather the key data emitted by your process, regardless of its state. Listen carefully. Your process is talking to you.