OEE and In-process Inspection


Hello.. long time lurker, first time poster. I searched the forums, but apparently I didn't use the right keywords. So, I apologize if this has been answered.

I work at a Precision Machine Shop (Job Shop) that is much more than it is. We are actually more of a production shop because of the volumes we produce. The products vary from small prototype jobs, to mass volume manufacturing of components, to mass volume assemblies from the various components we produce. So, as the new QM walking around and observing, I started questioning what their expected output is per Job (per hour/day/etc) and how do they know if they are hitting their goals because they had no metrics. So, long story short, we started talking about OEE/TEEP. Coming from an automotive background, I was always taught that OEE is calculated from Cycle Start to Finish Goods (from the Cell, Machine, etc.) As I observed a few operators, I noticed that they measure various critical characteristics on components in intervals. When the discussion of OEE was brought up on what we should monitor (i.e. Downtime, Breaks, etc.), I noted that you should be including the in-process inspection for total cycle time, since no product is approved without it. I got pushback from the team saying that we should only be monitoring the aforementioned. The machine is on a fixed cycle time because of the programming. That's easy to calculate. However, the product is not officially approved until the operator does their checks and moves them to either scrap or finished goods. Shouldn't this be considered since it is a part of the process?

Here is a simplified process we do:
Set-up/Change-over completed, FAI signed off, Cycle start.​
1. Machine cycle time is 5min.​
2. Operator removes parts from machine every 30 min. (They run multiple machines)​
3. Operator checks the six pieces for critical dimensions X,Y,Z for compliance.​
4. Operator moves parts to Finished Goods or Scrap.​
While the machine is steadily pumping out parts every 5min (Obviously some faster and slower on others), they are only looking to see downtime from the machine (i.e. offset changes, tool changes, machine breakdown, etc.). However, until the parts have been deemed OK and moved to Finished Goods, the process hasn't completed its cycle.

Am I wrong about this? Should this not be calculated for total cycle time?
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Nevermind.. The answer is, Yes.

Total Cycle Time: This includes all machines, processes, and, classes of cycle time through which a product must pass to become a finished product. This is not lead time, but does help in determining it.
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We appreciate your coming back to the discussion and letting us know your answer.

Of interest: Overall equipment effectiveness - Wikipedia

One thing of interest to consider is where goods go into "work in process" storage where they may remain for weeks or even months before advancing to the next process step.
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