Process Flow Diagram

While discussing the PFMEA we are inevitably drawn to the topic of the process flow diagram. Where I work we and our suppliers are supposed to have a process flow diagram. The requirement is somewhat vague, I guess. And when I say "have a PFD..." I mean, we should have and UTILIZE an effective PFD. The PFD shown below would fit the letter of the law. In the illustrated case the manufacturer is just describing, for sales purposes, the process steps that their piezo actuator goes through. The instructions from the AIAG APQP Manual state:

The process flow chart is a schematic representation of the current or proposed process flow. It can be used to analyze sources of variations of machines, materials, methods, and manpower from the beginning to end of a manufacturing or assembly process. It is used to emphasize the impact of sources of variation on the process. The flow chart helps to analyze the totalprocess rather than individual steps in the process. The flow chart assists
the organization’s product quality planning team to focus on the process when conducting the PFMEA and designing the Control Plan.

There is a process flow chart checklist in the appendix. The checklist is focused on including steps in the process, but not process description

However, when a NPD team is working to develop a manufacturing process they need to define the process in detail, including inputs and outputs. A complete PFD is essential for the PFMEA discussion.


This PFD is shown at noliac.com