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Common cause variation is the predictable, repetitive, systemic portion of variation. Contrast this with special cause variation, caused by unusual occurrences. Common cause variation, in a nutshell, is the consistent random (or random appearing) fluctuation built into a process. It is also frequently referred to as noise. While common cause Read more…
The “7 Basic Tools of Quality“ (or 7 QC Tools) is a set of relatively simple data analysis tools used to support continuous improvement efforts, specifically as they relate to quality. These tools are fairly straightforward in that they don’t require sophisticated statistics to use though control charts do border Read more…
The 6 P’s is a mnemonic tool similar to the 6 M’s. Both are used to categorize causes on an Ishikawa (cause & effect) diagram. The 6 M’s were traditionally used for fishbone diagrams on the shop floor or other production environments. The 6 P’s originated when more and more Read more…
The 6 M’s are a mnemonic tool used primarily during the creation of a cause & effect diagram. The 6 M’s are: Machines Methods Materials Mother Nature Manpower (People Power) Measurements Watch the 6 M’s Video Let’s look at the 6 M’s in more detail. Machines: Tools and equipment used Read more…
The Delphi method of predicting outcomes has been around for a long while but is not widely used in continuous improvement. It is the process of posing questions to many experts and using a summary of their results to further a discussion to predict a future outcome. One such panel Read more…
A production buffer is a type of inventory allocated specifically as a hedge against variation. The root cause of the unpredictability may be due to the normal variation of a process, or any of a variety of types of special cause variation. The latter causes include things like supplier unreliability, Read more…
Automated guided vehicles (sometimes called Automatic Guided Vehicles) are driverless vehicles that primarily perform transportation functions. In most cases, they support materials groups in distribution of raw materials and in movement of finished goods. These vehicles may either operate similar to a pallet jack, and carry the load, or as Read more…
Most processes change over time. A car will age, and as it undergoes normal wear and tear, gas mileage will worsen. It won’t be an overnight change, but it will trend downward. This is drift. Processes, with no visible changes, often slowly perform differently. A fixture may loosen up over Read more…
Production processes require assets to run them. You generally have choices. You can use a big machine that costs a lot of money but has tremendous functionality and flexibility. These machines, because of their cost, end up being used in several processes or for several products to defray the cost. Read more…
Value added work consists of the tasks that a customer is willing to pay for. Generally this is something that changes the form, fit, or function of raw materials. Note that it is very important to consider value from the customer perspective. In some cases, they will value something that Read more…
The work sequence is, not surprisingly, the order in which tasks are completed. Work sequence is also commonly referred to as the sequence of operations. Many tasks follow a logical order. Consider the assembly of a go kart. It makes sense that the tires are installed onto the wheels before Read more…
Yield is a quality ratio. It is calculated by dividing the number of good pieces of work by the number of pieces of work started and is expressed as a percent. If a process starts work on 100 items, for example, and 92 make it off the end of the Read more…