FMEA example

PFMEA Example: A Worked Process FMEA

A short, concrete Process FMEA example you can copy the structure from — multiple failure modes, causes, controls, and how the risk scoring works.

The fastest way to understand a PFMEA is to read one. Below is a short worked example for a common operation — drilling and inspecting a machined aluminum part.

The process step

Operation: 100.20 CNC Machining — machine the bore and faces of an aluminum manifold block.
Requirement (Product): Bore diameter within [drawing tolerance].

A few rows of the analysis

Failure Mode	Effect(s)	Cause	Prevention	Detection	Recommended Action
Bore oversize	Loose fit; potential leakage	Tool wear	Tool-change interval	In-process gauge	Tighten the change interval
Bore oversize	Loose fit; potential leakage	Wrong tool offset	Setup verification	First-off inspection	Error-proof offset entry
Bore undersize	Will not assemble	Insufficient depth of cut	Program review	Go / no-go gauge	Verify CNC program

Notice how a single failure mode ("bore oversize") has several distinct causes, each becoming its own row with its own controls — that's what a real FMEA looks like, not one line per step.

How to read the risk

Once your team fills in Severity, Occurrence, and Detection (1–10) for each row, you get:

• SEV × OCC — a quick criticality figure.
• RPN = S × O × D — the classic risk number.
• Action Priority — High / Medium / Low using the AIAG-VDA approach, which many auditors now prefer over RPN alone.

The rows with the highest priority get recommended actions, an owner, and a due date — then you re-rate after the fix.

← Back to Dropfeed