Maintenance & Reliability worked example

Spare Parts Reorder Point with reorder trigger quantity of 350 units: a worked example

This scenario runs the spare parts reorder point calculation on the strong side: reorder trigger quantity of 350 units, with every other input held at its documented default. Use it when deciding how early to trigger replenishment on a long-lead or downtime-critical spare item.

The inputs for this scenario

  • Reorder trigger quantity: 350 units (raised for this scenario; the documented default is 140)
  • Average daily spare demand: 4 units / day (unchanged)
  • Reorder safety multiplier: 1.1 x (unchanged)

Working through the calculation

  • Applying the documented formula (Base lead-time coverage = reorder trigger quantity รท average daily spare demand) to the inputs above produces each figure below.
  • At this operating point the engine returns 79.55 days for protected reorder coverage, the number this scenario is built around.
  • At this operating point the engine returns 87.5 days for base lead-time coverage.
  • At this operating point the engine returns 350 units for reorder trigger quantity.
  • At this operating point the engine returns 4 units / day for average daily demand.

How this compares with the baseline

  • Against the tool's baseline example, where reorder trigger quantity sits at 140 units and the headline result is 31.82 days, this scenario comes in 150% above the baseline at 79.55 days.
  • Use it when validating a CMMS min/max setting or asset BOM reorder point against the actual replenishment lead time for that spare. 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 Reorder Coverage: 79.55 days (headline result)
  • Base Lead-Time Coverage: 87.5 days
  • Reorder Trigger Quantity: 350 units
  • Average Daily Demand: 4 units / day

Run it with your numbers

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

Last reviewed 2026-05-12.