FMEAs can basically be classified into one of three possible types: process, functional, or component. All three of these FMEA types assess the impact of failures on system performance and safety to determine which failure modes require efforts to prevent, mitigate, or detect occurrence. The selection of a particular FMEA type indicates the intended scope of the analysis.

For example, you might choose to limit your assessment of possible failures to those that can occur during the manufacturing or assembly process of a product. Or, you might choose to limit it to failures that prevent you from meeting the functional requirements for a product design. When a comprehensive assessment of a product design is required, you would not want to limit your assessment in any manner but rather consider all possible failure modes for all system components.

The advantage of Windchill FMEA is that it supports any type of FMEA you want to perform. Additionally, if you have your own hybrid type of FMEA, or some customized FMEA format, the FMEA module can be adapted to meet your needs.

For the examples in this guide, we discuss and show the most common types employed: process, functional, and component. The following sections briefly discuss these types.

A process FMEA examines the ways that failures in a manufacturing or assembly process can affect the operation and quality of a product or service. A process FMEA can be performed at any level to evaluate possible failure modes in the process and limitations in equipment, tooling, gauges, or operator training. The information collected can help to determine what can be done to prevent potential failures prior to the first production run. You can then take actions to reduce your exposure to risks deemed unacceptable.

A functional FMEA examines the intended functions that a product, process, or service is to perform rather than the characteristics of the specific implementation. When a functional FMEA is developed, a functional block diagram is typically used to identify the top-level failures for each block in the diagram. For example, a functional FMEA would consider that a capacitor is intended to regulate voltage and then analyze the effects of the capacitor failing to regulate voltage. It would not analyze what would occur if the capacitor fails open or fails shorted.

A component FMEA examines the characteristics of a specific implementation to ensure that the design complies with requirements for failures that can cause loss of end-item function, single-point failures, and fault detection and isolation. Once individual items of a system are identified in the later design and development phases, component FMEAs can assess the causes and effects of failure modes on the lowest-level system items. Component FMEAs for hardware, commonly referred to as piece-part FMEAs, are the most common type.