Mean Time Between Failure (MTBF) is the average of the operating time of an equipment or machine, between two failures incidences, observed for a particular time period. The observed Time period may be a week, a month, a year etc.
MTBF metrics helps us with information regarding the availability and reliability of the equipment. The higher MTBF metrics, the longer the Equipment will continue to run before breaking down for a repair.
Calculating MTBF
MTBF is calculated using the formula
MTBF = Total operational time / Total number of breakdowns
The running time can be calculated by reducing total breakdown time from the available time, for a particular time period. Make sure to reduce other stoppages such as Power cut, lunch break etc. We need to take into consideration the time the machine is actually producing.
Total number of breakdown is the total no of stoppages of the machine due to equipment failure for a particular time period.
Example of MTBF calculation
Let us look at an example to understand how to calculate the Mean Time Between Failure for a month time period
Shift Duration in a month = 480 Minutes x 2 Shifts x 26 working days
= 24960 Minutes
Breakdown hours in a month – 1460 Minutes
Other Minor stoppages in a month – 850 Min
Total number of Breakdown occurrences = 12
Let us now calculate
MTBF = Total operational time / Total number of breakdowns
Total operational time = (24960-850) – 1460
= 22650 minutes
Total number of breakdowns = 12
Mean Time Between Failure (MTBF) = 22650 / 12
= 1887.5 minutes
MTBF metrics helps us with information regarding the availability and reliability of the equipment. When the MTBF is higher it indicates that the equipment is in operation for a higher amount of time continuously without any stoppages. Higher the MTBF more availability of the equipment. This will result in higher Overall Equipment Effectiveness (OEE).
When the MTBF is lesser it indicates that the frequency of breakdown is higher which will have negative impact to the process productivity.
This data will also help us to compare the equipment performance with other equipment performance and also to compare its own performance with the historical data.
Higher the MTBF more reliable the equipment.
We believe this blog would have helped you have crisp and clear information about what is Mean Time Between Failure (MTBF), calculating MTBF and the inference of the calculated date. Please do leave your comments and questions which will help us know the feedback.
You can read about Mean Time To Repair – MTTR to relate between the MTBF and MTTR for better understanding.
