Quick FMECA as top-down approach

The previous chapter discussed the 7 steps of FMECA as a bottom-up approach. As an alternative, we can use a top-down approach, called the Quick FMECA. A brief definition of the top-down approach was introduced in section Top-down (Quick FMECA). We will now explain this approach in more detail.

A Quick FMECA can be performed on a FMECA System and Serial or Redundant System level in Asset Strategy Optimization, assuming the system contains sub systems, representing a complex system, such as a plant or a factory. The goal is to identify the subsystems with the highest risk.

In summary, performing a Quick FMECA means that for a chosen branch of high-level systems, the user indicates Probability of a failure mode and the Effect of that failure on the various business objectives. Using the formula Risk = Probability x Effect, a risk number results. Based on the risk matrix, the risk number is compared to the threshold set in the risk matrix. If the risk is higher than the threshold, the failure mode will be marked as critical, otherwise it will be marked as not critical.

Failure modes can also be edited in this view, while there is a Comments field that can be used to add more context.

To start a Quick FMECA

1. Select an FMECA system, serial or redundant system in the Tree view.

2. Select Quick FMECA from the hamburger menu .

   The Quick FMECA grid opens for the selected system, showing the path to the selected system at the top of the screen.

   The grid view lists all subsystems of the chosen system, which can be identified by looking at the path and subsystem name.

3. For each failure mode, fill in the MTTF classification:

   1. For the intended failure mode, click in the MTTF column.

   2. Select the appropriate probability.

      The chosen value is automatically stored.

4. Repeat step 3 for the MTTR (mean time to repair) values.

5. For each failure mode, fill in the effect the failure mode will have on the specific business objective:

   1. For the intended failure mode, click in one of the business objectives columns, for instance 'Safety'.

   2. Select the appropriate effect from the list.

      The chosen value is automatically stored.

6. Repeat the previous step for all business objectives for this failure mode.

7. Repeat previous steps until all probability and effect columns are filled.

8. Check the Critical column to learn the criticality of each failure modes.

Note: You can easily distinguish the critical from the non-critical failure modes, by dragging the column header Critical to the Group by column at the top of the grid. This will separate the non-critical failure modes from the critical ones.