Relyence User Guide
Elements of a PFMEA

Elements of a PFMEA

A PFMEA contains four main elements in an Analysis: 

  • The P-Diagram, or Parameter Diagram, is a useful tool used to determine and document inputs and intended outputs for the item or process under review, along with unintended outputs (sometimes called error states), noise factors, and control factors. Function details, functional requirements, and non-functional requirements may also be documented.
  • The Process Flow Diagram (PFD) or Process Flow Table (PFT) defines the detailed steps of your process. The PFD and PFT are used for the same purpose: to describe the process steps. If you prefer to view and maintain this information in a graphical format, use a PFD. If you prefer a worksheet format, use the PFT. Or, you can use them both. Relyence FMEA will make sure the process information is kept in sync between your PFD and PFT.
  • The PFMEA Worksheet is the heart of your analysis, and contains information on all potential failure modes, and their effects, causes, actions, and risk rankings.
  • The Control Plan (CP) defines the methods you will use to ensure your process remains in control. Control Plans are also referred to as Process Control Plans (PCP). In Relyence FMEA, Control Plan (CP) is used.

In Relyence FMEA, the Process Steps on the PFD/PFT, PFMEA Worksheet, and CP remain in sync. This means that data that applies to all three elements is linked, so that adding or editing data in one place automatically is reflected in the others. This ensures that your PFMEA work is not only efficient, but also avoids costly mistakes that can occur when data is not carried through your entire analysis.

You may choose to use each of these three elements or use any combination of them you desire, along with the P-Diagram if needed. For example, you may just want to use the PFMEA Worksheet. If you choose to start your analysis without all four elements, you can easily add in the other elements at any time. The advantage of Relyence FMEA is that the shared data will be in place and ready for you without the need to copy and paste information.

The following topics provide details of the four elements of a PFMEA: P-Diagrams, Process Flow Table and Diagram (PFD/PFT), PFMEA Worksheet, and Control Plan (CP).