Maintenance & Reliability worked example

Mean Time Between Maintenance with total operating time of 18,000 hr: a worked example

Push total operating time up to 18,000 hr and the picture changes. This example computes every intermediate figure at that operating point. Use it when you want a broader interval than MTBF that includes both preventive and corrective maintenance demand.

The inputs for this scenario

  • Total operating time: 18,000 hr (raised for this scenario; the documented default is 7,200)
  • Total maintenance actions: 30 actions (unchanged)
  • Normalization factor: 1 x (unchanged)

Working through the calculation

  • Applying the documented formula (MTBM = total operating time รท total maintenance actions) to the inputs above produces each figure below.
  • At this operating point the engine returns 600 hr / action for mtbm, the number this scenario is built around.
  • At this operating point the engine returns 600 hr / action for base hours per maintenance action.
  • At this operating point the engine returns 1 x for normalization factor.
  • At this operating point the engine returns 30 value for maintenance actions.

How this compares with the baseline

  • Against the tool's baseline example, where total operating time sits at 7,200 hr and the headline result is 240 hr / action, this scenario comes in 150% above the baseline at 600 hr / action.
  • It computes average operating hours per maintenance action, then scales that by a normalization factor to match your reporting basis. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • MTBM: 600 hr / action (headline result)
  • Base Hours per Maintenance Action: 600 hr / action
  • Normalization Factor: 1 x
  • Maintenance Actions: 30 value

Run it with your numbers

  • Every input above is editable in the live Mean Time Between Maintenance calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.