Using the Reverse FMEA to Validate Performance
Take a look at the performance of your FMEA and how the Reverse FMEA can help validate it.
We are in a state in which we are transitioning from one methodology, where we calculate what is called RPN into a new methodology called AP. The intent remains the same, whether you are talking about RPN or AP you are using a combination of severity, occurrence, and detection. In effect, what you were creating is a risk profile and the risk profile is largely created during the inception of the product or process.
The team gets together, and they estimate that risk profile. What the Reverse FMEA does after your FMEA is completed and just hit the floor at an appropriate time, you want to go and see if the risk profile that you set made the intended effect you were planning on.
Metric Examples, PPM, and Scrap
When it comes to occurrence, traditional occurrence values wrongly have been calculated by the number of parts you shipped and the number parts you got returned. If you shipped a million parts and you got two back you would say, well, my occurrence is very, very low.
Let’s say you have a rework station where 50% of the parts go through your rework. Occurrence is sky high so when we look at scrap rates here is something you may not know every piece of scrap present in your process. needs to be on the Process FMEA so your scrap numbers should give you a validation of your risk profile; this of course can be tied into Cost of Quality.
This allows us to link it into the business system so let’s say that you have $80,000 of scrap you go to do a Reverse FMEA. You pull the FMEA up and you realize that your initial occurrence level was very low, however, based on $80,000 of scrap, it is much higher than the value that the Reverse FMEA provides.
So, when you’re looking at this one thing what you look at is the Poka Yokes you put in place. Are they still protecting you? The occurrence values that you put in place, are they still valid? The work instructions and the forums, that you put in place as controls against failure are they performing is you expect?
This is how the Reverse FMEA validates the performance of your manufacturing processes.
If you would like to learn more about Reverse FMEA check out our trainings or related content linked below.
Stay Ahead of the Curve
Subscribe to our newsletter.