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Packaging Equipment Reliability Metrics Calculator

Estimate mean time between corrective failures (MTBF), mean corrective repair time (MTTR), and steady-state inherent availability from one defined equipment boundary and observation record. Formulas: MTBF = accumulated operating hours / corrective failure count; MTTR = corrective repair hours / failure count; inherent availability = MTBF / (MTBF + MTTR). The steady-state model assumes constant failure and repair rates. It excludes preventive maintenance, administrative delay, and logistics delay; it is not operational availability. Source: NASA, Formulas: Inherent Availability and Reliability with Constant Failure and Repair Rates, https://www.nasa.gov/wp-content/uploads/2023/11/170508-formulas-inherent-availability-and-reliability-with-constant-failure-and-repair-rates.pdf.

Example values are prefilled to demonstrate the calculation. Replace them with values for your product, package, equipment, and operating conditions.

Inputs

Operating and repair history

Range: at least 0 h

Enter accumulated run time for the same machine or explicitly defined equipment group and observation window as the failure count.

Range: at least 0 count

Count whole corrective failure events for the same equipment boundary and observation window as its operating hours and repair time.

Range: at least 0 h

Sum active equipment downtime for corrective repairs of those failures, not technician labor-hours. Exclude preventive maintenance and administrative/logistics delay; use the same window and equipment boundary as the other inputs.

Result

Valid
Inherent availability estimate
0.98
Mean operating time between corrective failures
100.00 h
Mean active corrective equipment downtime per failure
2.00 h
Availability basis and exclusions
This is a steady-state inherent availability estimate based on corrective failures and active repair time. It excludes preventive-maintenance downtime and administrative, logistics, or parts delays; it is not operational availability or a compliance determination.

MTBF, MTTR, and availability calculations

Mean operating time between corrective failures
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Mean active corrective equipment downtime per failure
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Inherent availability estimate
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