The simple process that follows can be used to drive useful life to deliver the desired mean time between failures (MTBF):
- Subtracting the as-found condition from the as-left condition will determine the amount of deterioration.
- Dividing the amount of deterioration by the amount of time between when as-left and as-found measurements were made will determine the deterioration rate.
- Identifying the condition at which a component will no longer be able to perform its required function.
- Calculating the time required to deteriorate from the current condition to the point of failure.
- Comparing the time required to deteriorate to failure to the desired MTBF.
- Replacing all elements that will not survive beyond the run length needed to support the targeted MTBF.
Tip from Critical Connections by Daniel Daley