- Special Characteristics (Critical and Significant)
- Collaboration on Special Characteristics
- Characteristics as Inputs to PFMEA
- Practical Application of the Design FMEA Technique
- Robustness Tools: Interface Analysis / Boundary (Block) Diagrams; Parameter Diagram (P Diagram)
The Design FMEA (DFMEA) and Process FMEA (PFMEA) have several links that are generally not understood. The primary link between the DFMEA and PFMEA is the special characteristic. The special characteristic is a conversion of a cause of failure the design team has determined to be at risk. The special controls necessary to address the risk should be discussed between manufacturing and product design. THE PFMEA should address the risk through analysis.
Other important links to consider are robustness tools. Boundary and Parameter Diagrams help the design team to consider noise factors and interfaces which may hinder performance of the product. Process Flow Diagrams (PFD) are useful to link design features to process steps for proper cause identification. Input sources of variation and outputs are also useful for PFMEA development.