PFMEA Help - Page 39 in the 3rd Ed. of the FMEA Manual

[Sam]

PFMEA Help

Page 39 in the 3rd Ed. of the FMEA manual.
The statement;
"However, in preparing the FMEA, assume that the incoming part(s)/materials are correct."
Does this mean incoming part(s)/materials at receiving or at each process stage.
Ex.
Process A pulls material from stock and delivers tp process B. Does process B assume the material is correct or does process B check it.
Would there be a consideration for a potential failure of Process A to pull the incorrect material?

 

[TLE]

When we make FMEA, we assume that incoming parts are correct, too. Also we know that this is not true.
But otherwise we would spin around.
When we start with FMEA we define that process-steps we want to look in (reasons for the selection are safty, costs, failures, customer,etc.). And for these processes we assume that the incoming material is ok (definition!), otherwise we have selected the wrong process-step.

Hope it helps
Thorsten

 

[Bill Ryan - 2007]

Does this mean incoming part(s)/materials at receiving or at each process stage.

The answer is YES (to both).

The intention behind the statement in the FMEA manual is to have control of your product at the processing step a feature or characteristic is produced (ie - prevention of nonconformances).

Sounds ideal, on paper. In practice, we too "inspect quality in" further downstream for some quality characteristics, but with respect to the FMEA, I can only DETECT the nonconformance downstream.

As far as "Process A" pulling the incorrect material - if it can happen then YES it should be a Failure Mode on your PFMEA, perhaps in a "uniquely" identified process step such as a "transfer".

Thorsten is correct in that you will get into the "cyclical" argument of "Is this a MODE or a CAUSE?" if you don't address it at the operation it is produced.

Hope that helps some.

Bill

 

[Sam]

Thanks all for the feedback.