TYPES OF FMEAS

There are many types of FMEAs (see Figure 6.1). However, the main ones are:

• System/Concept ” S/CFMEA. These are driven by system functions. A system is an organized set of parts or subsystems to accomplish one or more functions. System FMEAs are typically done very early, before specific hardware has been determined.

• Design ” DFMEA. A design FMEA is driven by part or component functions. A design/part is a unit of physical hardware that is considered a single replaceable part with respect to repair. Design FMEAs are typically done later in the development process when specific hardware has been determined.

• Manufacturing or Process ” PFMEA. A process FMEA is driven by process functions and part characteristics. A manufacturing process is a sequence of tasks that is organized to produce a product. A process FMEA can involve fabrication as well as assembly.

• Machinery ” MFMEA is driven by low volume machinery and equipment where large-scale testing is impractical prior to production and manufacture of the machinery and equipment. The MFMEA focuses on design changes to lower life cycle costs by improving the reliability and maintainability of the machinery and equipment.

Figure 6.1: Types of FMEA.

Note  

Service, software, and environmental FMEAs are additional variations. However, in this chapter we will focus only on design, process, and machinery FMEAs. The other FMEAs follow the same rationale as the design and process FMEAs.