Process flow & PFMEA for production planning and simulation activities?

DuncanGibbons

Involved In Discussions
Is it require or customary to develop a process flow diagram, PFMEA and control plan for production planning activities such as design reviews, risk analysis, scheduling, CAM and toolpath generation, design simulation and process simulation etc?

I know process flow diagram, PFMEA and control plans are required per APQP requirements, but these are generally production planning activities. If required would there be a process flow diagram on how the process flow diagram shall be developed, and a PFMEA for risks when developing a PFMEA etc?

Thanks
 

Tidge

Trusted Information Resource
A process flow diagram can help folks understand elements of any process (including design and development) but there isn't much value to be extracted from performing a Failure Modes Effects and Analysis for a development process itself. A classic FMEA is a prioritization scheme used to address identified failure modes via risk controls; with a well-defined development process you don't need much more that 'defect awareness'.

More important is to have some sort of corrective/preventive action process to support other processes.
 

DuncanGibbons

Involved In Discussions
Thanks for the help,

So it should make more sense to include flow diagrams and FMEAs in the QMS process, then for each product line perform process flows, FMEAs and control plans for the manufacturing-specific activities, ie. not for planning activities?
 

Tidge

Trusted Information Resource
I wouldn't do anything like FMEA for QMS processes. A QMS process is either implemented for compliance or a because of a self-motivated interest in Quality. FMEA allow you to prioritize controls to improve process outcomes... with the assumption that there will be some level of undesirable outcomes that you will tolerate. This doesn't make sense from a compliance perspective (you are either compliant or you are not) and in the case of self-motivated interest the rating scales and acceptance criteria will be so arbitrary that an FMEA won't provide any tangible benefit. FMEA are supposed to be living documents, and so unless you want to commit to 'periodic review' of them they will be nigh useless.

A QMS process flow diagram can help people understand the order of things and the outcomes at decision points, but I have seen them get too complicated too quickly. For most processes, there isn't much need beyond identifying inputs to and outputs of the process. My experiences have been that trying to be overly prescriptive within a general process provides positive feedback that ends in a bad place, such as:
  • Procedures that become full of 'guardrails'
  • Procedures that become full of 'loopholes'
  • Associates unwilling to take action because 'the procedure doesn't tell me how to do my job'
  • Associates willing to bend/break core tenets of the process because 'the procedure doesn't forbid from doing this'
 

Tagin

Trusted Information Resource
I know of one company that used PFMEAs to address ISO 9001 "risk-based thinking" requirement, by doing PFMEAs for all their QMS processes. It apparently works for them, and I am intrigued by the idea. Of course, you would still have your product-specific PFMEAs.
 

DuncanGibbons

Involved In Discussions
I know of one company that used PFMEAs to address ISO 9001 "risk-based thinking" requirement, by doing PFMEAs for all their QMS processes. It apparently works for them, and I am intrigued by the idea. Of course, you would still have your product-specific PFMEAs.

Hi Tagin, yeah this is what I was wondering about. Do they have a PFMEA for the PFMEA qms process as well? i.e. what are the risks involved with the risk management process? xD

And then for the product-specific process flow, do they just reference these processes and PFMEA's already setup and living. Or would they create new ones specifically for the product process in question?
 

Tagin

Trusted Information Resource
Hi Tagin, yeah this is what I was wondering about. Do they have a PFMEA for the PFMEA qms process as well? i.e. what are the risks involved with the risk management process? xD

And then for the product-specific process flow, do they just reference these processes and PFMEA's already setup and living. Or would they create new ones specifically for the product process in question?

Alas, I don't know the details of their implementation - I was only told about it third-hand.
 

Jim Wynne

Leader
Admin
Hi Tagin, yeah this is what I was wondering about. Do they have a PFMEA for the PFMEA qms process as well? i.e. what are the risks involved with the risk management process? xD
You're creating a potential infinite regress here. It has to stop somewhere.

And then for the product-specific process flow, do they just reference these processes and PFMEA's already setup and living. Or would they create new ones specifically for the product process in question?
If you use the standard PFMEA process for anything other than production processes, you're asking it to do something it wasn't designed to do. In my experience it doesn't work very well for what it was designed to do. In any event, you shouldn't be trying to force round pegs into square holes.
 

tbdennis1

Registered
Can a customer demand processes be added to FMEA? We utilize incoming on product that shoots and ships. Other processes is a skip lot.
 

Tidge

Trusted Information Resource
Can a customer demand processes be added to FMEA? We utilize incoming on product that shoots and ships. Other processes is a skip lot.

If we are talking about a well-established process that is well-represented in an analysis... It strikes me as reasonable that a customer can "ask" for more (or more effective) risk controls. It also seems reasonable to add a cost to the quote for the outputs of the process, depending on the nature of the contract.
 
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