Countless proverbs have been made over the years of when things do not go as anticipated: “Men make plans, and God laughs”, “If anything can go wrong, it will”, etc. In one’s personal life, many people just shrug their shoulders, and go about their day; however if a multi-million dollar investment, or someone’s life, is on the line, engineers need to take steps to prevent it from happening again.
One of the first tools used to diagnose problems is an Ishikawa Diagram (named for Kaoru Ishikawa, who popularized its use in the 1960s), also known as a fishbone diagram (named after its graphical resemblance to the skeleton of a fish).[1] The problem being diagnosed (the effect) is written at the fish’s “head” on the right-hand side of the diagram, and the potential causes are written along the “ribs” with an arrow “spine” connecting them all.
As an example, let’s say that a widget company has the problem that some of their end products are unfit for sale (“Problem”). Engineers then brainstorm potential causes, and sort them along the appropriate ‘ribs’ depending on which category the cause falls into. For manufacturing, the categories tend to fall into one of the four “Ms”:
- (hu)Man: Is the operator doing their job as intended? Have they been fully trained on their tasks?
- Material: Is the design using the right raw material for the job? Is there a potential for issues with the suppliers?
- Method: Is there a problem with the procedure? Is there a better way to perform any of the fabrication steps?
- Machine: Are all the machines in proper functioning order? Have any components worn out to become outside of manufacturing tolerances?
Some manufacturers use additional “Ms”, such as “Mother Nature” (environmental conditions), Measurement, Management (proper investment in workforce and tooling), and/or Maintenance.
Once these potential causes are listed, they can then be investigated, and either ruled out of consideration, or further investigated as a potential root cause.
EMMA International has a team of experts ready to support your team with root cause analysis. Contact us today at 248-987-4497 or email us at info@emmainternational.com to learn more!
[1] <https://en.wikipedia.org/wiki/Ishikawa_diagram>
