Maintenance Management Resources Six sigma and lean manufacturing, it's all about money:
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This category is a per downtime occurrence entry, often overlooked in CMMS programs. Your existing method of reporting needs to meet the TDC recommendations below.
Two types of Band-Aid information...
Cost of this occurrence
Associate cost to permanent fix done later
Parts used for band-aid repair
Amount of times band-aided till permanent fix, etc.
Percentage of all other Downtime Metrics
What percent of full speed, increased scrap, extra
manpower, tool breakage, etc.
Before computers, band-aid cost was never tracked, which has led to it being overlooked in most cases now days. A good example is a case of required re-engineering. The facility had a two week wait for planned downtime to replace a bearing with a different type. In the mean time, up to 3 times a day maintenance would have to drag the welder to the machine to do a band-aid spot weld. (the vibration had it's effects.)
Looking at the maintenance time only resulted in 1.5 times per day average, at 15 minutes per day. This went on for 12 days, resulting in a total of 4.5 hours downtime till scheduled permanent fix. When deciding whether to shut down for repair, or wait till scheduled downtime, the 6 hours to do repair was the only consideration.
At first glance, the decision looks pretty sound, till you see the true cost with TDC. To keep it simple we will use just a few of the TDC metrics to make our decision.
True Band-Aid cost...
Estimated band-aid
time = 1X15 minutes per day (total 3 hours)
Labor for fix = 2
maintenance X 6 hours (12 man-hours)
= 1 QC inspection per start-up(1/4 hour )
Closer to True Down Time (TDC) cost of
Band-Aid TOTAL
$
10.00
$ 600.00
$ 300.00
$ 6.25
$ 916.25
Had the data monitoring and decision making processes in compliance with TDC been in place, would they have made the same decision? As long as they could still make their ship dates, or had inventory, I don't think a band-aid would have been the choice.
Without TDC they were looking at spending $45.00 now, and $90.00 approximately two weeks. Really they should have been looking at a conservative estimate of spending $916.25 now for a permanent fix, or $1511.25 with the band-aid for a permanent fix in 12 days (2+ times the cost). (Values based on fact that to get max ROI out of capital equipment, you should run equipment 24/7/365. There for even planned downtime has loss of 6 hours production.)
The example above is a very low cost one. Consider if the machine in question was a bottleneck, and the parts cost at that stage of production was $30 each. They might then be looking at a labor only estimate of $45, when the true cost would be in the thousands (100+ times the cost).
In summary, when looking at a band-aid decision, be sure to use manpower cost, not just their wages. Secondly, include all people involved in band-aid; maintenance, qc, set-up, power cost, machine depreciation, etc. Third, don't forget scrap cost and reduced production, just to name a few (bottleneck could cause similar cost throughout the plant). Last of all, take note that band-aid time estimates, and amount of times needed to be done are usually under estimated.
