Municipal Waste Sorting Equipment worked example

Spare Parts Buffer with wear-part daily consumption rate of 5 units / day: a worked example in municipal waste sorting equipment

This scenario runs the spare parts buffer calculation on the strong side: wear-part daily consumption rate of 5 units / day, with every other input held at its documented default. Use it when sizing a min and max in the CMMS for screen discs, baler wire, magnet belts, sorter valves, or other consumables you cannot afford to run short on.

The inputs for this scenario

  • Wear-part daily consumption rate: 5 units / day (raised for this scenario; the documented default is 2)
  • Supplier or rebuild lead time: 14 days (unchanged)
  • Safety stock buffer: 6 units (unchanged)

Working through the calculation

  • Applying the documented formula (Cycle stock = daily consumption rate x supplier or rebuild lead time) to the inputs above produces each figure below.
  • At this operating point the engine returns 0.06 units for protected days of supply, the number this scenario is built around.
  • At this operating point the engine returns 0.36 days for unprotected days.
  • At this operating point the engine returns 5 pieces for inventory.
  • At this operating point the engine returns 14 pieces / day for daily usage.

How this compares with the baseline

  • Against the tool's baseline example, where wear-part daily consumption rate sits at 2 units / day and the headline result is 0.02 units, this scenario comes in 150% above the baseline at 0.06 units.
  • Use it when setting reorder points and min/max levels for fast-moving wear parts like screen discs, belt cleats, conveyor rollers, and optical-sorter nozzles. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Protected days of supply: 0.06 units (headline result)
  • Unprotected days: 0.36 days
  • Inventory: 5 pieces
  • Daily usage: 14 pieces / day

Run it with your numbers

  • Every input above is editable in the live Spare Parts Buffer calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.