Tuesday, October 05, 2010
TPM in Action
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 was also 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 don’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, we have the serious potential of electrocuting someone.
Preventing the loss of life is the highest of priority over any of the six big losses found in the OEE (Overall Equipment Effectiveness) metric.
After doing some root cause analysis, the team concluded 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 improve 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 preventative actions by improving the machine design. The end result is a more reliable, more efficient, safer machine available for making parts.