AIAG FMEA 4? Ed. Explanation: Relationship between PFMEA and Special Characteristics

[diegofromitaly]

AIAG FMEA 4° Ed. Explanation: Relationship between PFMEA and Special Characteristics

Dear,

When it can be considered complying the product from a previous step of production? Always?


What is the relationship between PFMEA and special characteristics? Only inform the design engineer if gravity are over 9 or 10?

Thank you...

 

[qusys]

Re: Explanation on AIAG Fmea 4° Ed., special characteristics

Dear,

When it can be considered complying the product from a previous step of production? Always?


What is the relationship between PFMEA and special characteristics? Only inform the design engineer if gravity are over 9 or 10?

Thank you...

You shall take action when severity is 9 or 10. Consider that in FMEA severity can be only modified with a change in design ( if you are talking of product FMEA).
As to the first question , I did not undestand, You shall link PMEA with Control plan for the whole process flow .

 

[diegofromitaly]

Re: Explanation on AIAG Fmea 4° Ed., special characteristics

Hi qusys...the question are...I compile a PFMEA, the product have a flow in the process, i write a function, i must to consider ALWAYS complying the product of the previous step of production?

 

[qusys]

Re: Explanation on AIAG Fmea 4° Ed., special characteristics

Hi qusys...the question are...I compile a PFMEA, the product have a flow in the process, i write a function, i must to consider ALWAYS complying the product of the previous step of production?

You shall identify potential failure for the several step of your flow.
You can have multiple . What does it mean " complying the product of the previous step?"

 

[Jim Wynne]

Re: Explanation on AIAG Fmea 4° Ed., special characteristics

You shall take action when severity is 9 or 10.

No--sometimes there will be no actions that can be taken to lower the risk and the RPN.

Consider that in FMEA severity can be only modified with a change in design ( if you are talking of product FMEA).

This is also not always true. It's true in the great majority of cases, but not all.

 

[Jim Wynne]

Re: Explanation on AIAG Fmea 4° Ed., special characteristics

Dear,

When it can be considered complying the product from a previous step of production? Always?

In general, only potential failure modes created in the present operation should be considered. In other words, it should be considered that material coming into the process or operation is in conformance. Inspection operations, when considered as a separate line item in a PFMEA, are an exception. For inspection, it should be considered that the condition of the product is unknown.

What is the relationship between PFMEA and special characteristics? Only inform the design engineer if gravity are over 9 or 10?

Special characteristics generally must be identified on the PFMEA form, but if the Severity factor is high, one of the things you might consider is consulting with the design authority to determine if something can be changed. This won't always be the case. If Severity is high, you need make sure you understand the risks and the variation that contributes to it and determine whether action can be taken to reduce the risk.

 

[qusys]

Re: Explanation on AIAG Fmea 4° Ed., special characteristics

No--sometimes there will be no actions that can be taken to lower the risk and the RPN.
Agree with you. but in the real case case I have seen some organization tale actions, check at RPN at aiming at reducing occurrence or increasing detection, in any case

This is also not always true. It's true in the great majority of cases, but not all.

 

[Carmine]

Re: AIAG FMEA 4° Ed. Explanation: Relationship between PFMEA and Special Characterist

I can suggest : Special and Critical Charteristic you have to take from your Drawings. Then there are the High Impact and Sefty Operator that comes from your process

 

[hkrishnan1983]

Re: AIAG FMEA 4° Ed. Explanation: Relationship between PFMEA and Special Characterist

Carmine,

I would suggest you the following points,

1. Arrive SC/CC matrix from the DFMEA

2. Take 2D drawings, Process flow documents

3. Take PTDB(Past trouble data bank),it contains list of failures(internal, warranty & customer complaints) as a key input for FMEA

4. Do stage-wise brainstorming w.r.t man,machine,method & material

5. list out possible potential failure modes

6. assign severity, occurence & detection

7. caluculate Risk(RPN)

Finally, update the FMEA & reduce the RPN threasold limit as a continual improvement activity.

Take this input and develop control plan.

From control plan, arrive Work instructions, list of poka-yoke etc as applicable..

Thanks, Harikrishnan