Would a Leak be a Failure Mode on a Design FMEA?

If the product we are designing includes air springs to cushion a load should leaking be considered a Potential Failure Mode on our DFMEA? There is some thought here that leaks are a process failure not a design failure so leaks shouldn't be on our DFMEA but on our PFMEA.

Re: Would a Leak be a Failure Mode on a DFMEA?

In most cases, a leak should be noted as a potential failure mode on the Design FMEA, and controls put in place. Then, that would direct the Process FMEA to identify the points in the process where leaks could occur, and control them.

When in doubt, put it in. It won't be wrong...

Re: Would a Leak be a Failure Mode on a DFMEA?

topnotch said:

If the product we are designing includes air springs to cushion a load should leaking be considered a Potential Failure Mode on our DFMEA? There is some thought here that leaks are a process failure not a design failure so leaks shouldn't be on our DFMEA but on our PFMEA.

Click to expand...

Why not both?

In design, the hazards stem from inadequate design, i.e. even if all parts are flawless and the assembly is perfect etc. it still may leak (e.g. an interference fit was not specified properly, a seal material compression set value is too big or unknown etc.).

In process, the risk is that although the theoretical design is adequate, something along the process undermines the sealing - parts defects, wrong assembly etc.

Cheers,
Ronen.