While recently teaching about Total Productive Maintenance (TPM) using the learn-by-doing approach, we were presented with a great learning opportunity. Our first task was to get our hands dirty in giving the selected machine a deep and thorough cleaning. This cleaning is not just to make the machine look good; we were inspecting the machine while cleaning. This deep cleaning process paid particular attention to those hard-to-reach spots not normally seen by the machine operator on a daily basis.
We did find many issues with this machine that required repair during this deep clean. This also was accompanied with many comments like “I never knew that before”, “What’s that?”, “I can’t believe how much dirt and chips were under here” and “No wonder it leaks, all the drain holes are plugged up.” There were several other comments made that would make a sailor blush, and I’ll just leave it to your imagination.
In the middle of our partial disassembly of the machine to reach those places where the sun doesn’t shine, we found one major problem, a significant rip in the protective sheath of the main control wiring under the machine against the chip conveyor system. It would have never been seen walking around the machine under normal inspection.
With the wires unprotected and naked to the world, we have the potential of a major breakdown. Not only would a failure involving these wires cause a very expensive repair bill with significant downtime, but we have the serious potential of electrocuting someone.
Preventing the loss of life is the highest priority over any of the six big losses found in the overall equipment effectiveness (OEE) metric.
After doing some root cause analysis, the team concluded that the original poor design of the machine (thinner sheath material, plastic elbow joints and poor routing location under the machine) was the main root cause. After the new and improved material arrived the next day (thicker sheath and cast metal elbows), the team replaced the wire covering and re-routed the wiring to the back of the machine (instead of under the machine), making it free and clear of the chip conveyor system.
Our TPM approach included corrective and preventive actions by improving the machine design. The end result is a more reliable, more efficient, safer machine available for making parts.
About the author:
Mike Wroblewski started his lean journey with instruction in quick die change from Shigeo Shingo. Mike is currently a senior operations consultant for Gemba Consulting North America LLC. He also writes a blog called “Got Boondoggle?” featuring lean and Six Sigma topics. You can contact Mike at MWroblewski@gemba.com.