Mean Time Between Failure

Mean Time Between Failure. A process where a regularly occurring event interrupts the regular flow of work.

1. Generate the Main Work - There are two items in this model. Item 1, generated in this block, is the standard 'physical' item that is moving through the process. Item 1 follows the blue/purple path. 
2. Create the Interrupting Event - The second type of item, Downtime Event, is set as initial inventory in this queue and set with a priority of 1. Setting this priority allows this item to jump to the front of the Queue when it arrives in that block.
3. Model the Time Between Failures - The Downtime Event will loop during the simulation run, following the red/purple path. It spends time in MTBF to represent the time between failures.
4. Interrupt the Main Work with the Downtime Event - This Activity Block processes Item 1 with parameters that represent the normal work of the process. The Downtime Event item uses special processing time parameters, representing the Mean Time to Repair (MTTR).When the Downtime Event spends time in the Activity block, it prevents the main work of Item 1 from being completed.
5. Count the Number of Downtime Cycles - This block counts the number of times the downtime event occurred.

Note: This example is also one way to model a meeting! It can help manage meetings that interrupt the regular flow of work and slow down day-to-day operations.