Mean time between failures definition
Mean time between failures (MTBF) is a way to measure how long a mechanical or electronic system usually runs before it fails. It estimates how reliable a product or system is and is typically expressed in hours.
How mean time between failures works
- MTBF calculation starts with collecting data on how long a system operates before it fails.
- Each failure instance is recorded along with the time it occurred.
- MTBF is calculated by dividing the total time the system was running by the number of failures. For example, if a system operated for 1000 hours and experienced 10 failures, the MTBF would be 1000/10 = 100 hours.
Variations of mean time between failures
- Mean time to failure (MTTF). Used for non-repairable systems, where the focus is on the time until the first failure.
- Mean time to repair (MTTR). Measures how long it takes, on average, to fix a failed component or system.
- Mean time between system incidents (MTBSI). Looks at both failures and other problems that affect system performance but are not considered failures.
Uses of mean time between failures
- Electronics. MTBF is crucial for estimating how long products like circuit boards and power supplies will last.
- Manufacturing. MTBF is applied to measure the reliability of machinery and equipment. It helps plan maintenance, reduce downtime, and improve efficiency.
- Consumer goods. Manufacturers use MTBF to predict how long products like home appliances and vehicles will work.
- Aerospace and defense. MTBF is critical for making sure equipment like aircraft parts and defense systems are reliable and safe.
- Energy. MTBF helps keep power systems running reliably.
- Software engineering. Although traditionally a hardware metric, MTBF is also used to estimate how often software might fail.
- Project planning and risk management. In various industries, MTBF data helps plan for when equipment might fail and how to deal with it.