The 12% Maintenance Cut: Trading Cost Reduction Against Outage Risk
A two-line food-packaging plant spends $3.4 million per year on maintenance. Corporate has mandated a 12% reduction for the coming fiscal year. The site manager's draft plan contains three moves: cancel the $310,000/year contracted vibration and thermography route, defer two gearbox rebuilds budgeted at $85,000 each, and cut storeroom inventory by $250,000. Over the last 12 months the Line 2 filler has had six unplanned outages averaging 5.2 hours; contribution lost is $9,800 per hour. Maintenance overtime is running at 14% of labor cost. The reliability engineer is separately requesting $190,000 in capital to upgrade the filler's automatic lubrication system, estimating it would prevent 40% of those outages. Corporate wants the reduction plan submitted in three weeks and has said it will fund only projects with a payback under 24 months. The plant has no reliability cost accounting in place-downtime is tracked in hours but not converted to dollars.
1. Rank the three proposed cuts by risk and explain how you would quantify each one rather than argue qualitatively.
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The right frame is expected cost = frequency x consequence, applied to each cut.
- Deferring the two gearbox rebuilds. Unquantifiable as things stand, and that is the problem: there is no oil analysis on those boxes and the vibration route is about to be cancelled, so deferral is a blind bet on condition. A gearbox is typically long-lead and single-point. Before deferral is even discussable, you need wear-debris and vibration data plus a lead-time/downtime estimate. Absent that data, treat deferral as high risk and low confidence.
- Cancelling the PdM route. The number that matters is how many defects the route actually found in the last 24 months and how many of those became work orders that avoided a functional failure. Pull those work orders from the CMMS and value them at avoided outage cost. If the route generated, say, 15 actionable findings, even three avoided outages would be worth roughly 3 x 5.2 x $9,800 = $152,880, which exceeds the $310,000 contract only when compared against a like-for-like scope-so renegotiate scope rather than cancel.
- Cutting $250,000 of storeroom inventory. This is working capital, not expense; it does not help the P&L target and it is the fastest way to create the seal-style stockout. Segment by criticality and lead time first.
The known annual loss from filler outages is 6 x 5.2 x $9,800 = $305,760. Any cut that raises outage frequency by 20% consumes about $61,000/year, which must be netted against the saving.
2. Build the economic case for the $190,000 lubrication upgrade. State assumptions, test the sensitivity, and say whether you would submit it.
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Base arithmetic. 6 outages/year x 5.2 h x $9,800/h = $305,760 of lost contribution per year. A 40% reduction is $122,304/year. Payback = $190,000 / $122,304 = 1.55 years, about 18.7 months, inside the 24-month hurdle.
The assumption that carries the case. The 40% figure is only credible if lubrication-related failure modes actually account for 40% of those six outages. Check the work-order history: if lubrication is implicated in roughly 2.4 of the six events, the estimate holds; if it is implicated in one, the benefit is about $51,000/year and the payback is 3.7 years-outside the hurdle. State this explicitly rather than presenting 40% as fact.
Sensitivity. At 20% / 30% / 40% reduction, payback is 3.1 / 2.1 / 1.6 years. Present the table, not a single number.
Second caveat. Lost contribution is not the same as cash. If the line rebuilds finished-goods inventory and sales are not lost, finance may book the benefit at standard margin or at zero. Agree the costing convention with finance before submission.
Submit it, but as a staged proposal: fund the upgrade on the filler, and fund the data collection (lubrication-related failure codes, oil analysis) in parallel so the 40% assumption is verified within two quarters. Avoid claiming avoided overtime as a hard saving unless overtime would genuinely fall.
3. The 12% target equals $408,000. Your defensible savings total less than that. How do you respond to corporate, and what do you put in writing?
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Do not simply absorb the gap by spreading cuts evenly; that converts a financial problem into an unmanaged reliability problem.
- Separate recurring expense from one-off working capital. Inventory reduction releases cash once; it does not reduce next year's maintenance expense. Corporate must be told which is which, or the target will be met on paper and missed in reality.
- Build a tiered plan. Tier 1, no-regret: overtime reduction from 14% via planning discipline, contract scope renegotiation, deletion of duplicated routines, utility and consumable reduction. Tier 2, risk-managed: condition-verified deferral of the two gearboxes (requires data before commitment). Tier 3, capital-enabled: the $190,000 lubrication upgrade, which reduces future cost rather than cutting present capability.
- Quantify the residual gap in risk terms. If $408,000 cannot be reached without accepting a documented increase in failure probability, say so in writing with the numbers: each additional filler outage is $50,960 of contribution.
- Ask for the trade explicitly. "We can deliver $X in cost and $Y in working capital this year; delivering the full $408,000 requires accepting A, B, and C risks, which we will record." Get the acceptance signed.
- Use RONA language. $190,000 of capital avoiding $122,000/year of loss is a materially better return than most plant capital projects, and corporate finance understands that framing better than a reliability argument.