An exercise for the Achieving Effective FMEAs short course

1. Example FMEA Audit
 For this presentation, a truncated portion of a
fictitious Design FMEA on a Bicycle Hand Brake
Subsystem will be audited
 This FMEA has been selectively modified with errors
for evaluation of the 10 FMEA Quality Objectives.
 Exercise: for each of the 10 FMEA quality objectives,
review the FMEA example to assess how well it
achieves the FMEA Quality Objective. Make note of
how well this objective was achieved. Explain.
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2. Excerpt from Hand Brake Subsystem Design FMEA (with errors introduced for FMEA Quality Objectives evaluation)
Classification
Potential S Potential O Current Design Current Design D R
Item / Potential
Effect(s) of E Cause(s) of C Controls Controls E P Recommended Actions
Function Failure Mode V C
Failure Failure (Prevention) (Detection) T N
Hand Brake Insufficient friction Bicycle wheel does 10 Cable Binds due to 4 Design review of Bicycle system 2 80 Modify bicycle durability testing
Subsystem: delivered by hand not slow down inadequate lubrication brake system durability test # 789 to include periodic brake cable
Provide the correct brake subsystem when the brake or poor routing checks for binding
level of friction between brake pads lever is pulled
External foreign 2 3 60 Modify bicycle durability testing
between brake and wheels during potentially resulting
material reduces to include foreign material
pad assembly and heavy rain in accident.
friction (dust, leaves, etc.) at interface
wheel rim to safely conditions.
of brake pad and wheel rim
stop bicycle in the
required distance,
Cable breaks 6 Cable material Bicycle system 4 240 1. Require cable DFMEA /
under all operating
selection based on durability test # 789 PFMEA from supplier approved
conditions.
ANSI #ABC. by All-Terrain FMEA team.
2. Based on results of Cable
DFMEA, develop cable strength
test
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Brake Lever breaks 1 Design review of Bicycle system 1 10
brake system durability test # 789
Selected brake pad 2 2 40 Add bench test to evaluate
material does not adequate brake pad friction
apply required friction
to wheel
Hand Brake Brake system Brake system does 10 Brake cable mis- 6 Bicycle system 5 300 1. Develop new brake cable
Subsystem: misadjusted by not stop bicycle in adjusted by user durability test # 789 adjustment test that identifies
Brake system is bicycle user required distance mis-adjustment problems
easy to adjust and or is erratic, 2. Revise bicycle durability test
keep in optimal potentially resulting regimen to periodically check
working order. in accident. for brake cable, pad and lever
mis-adjustment
Brake pad mis- 1 Design review of Bicycle system 1 10
adjusted by user brake system durability test # 789
Brake lever mis- 1 Design review of Bicycle system 2 20
adjusted by user brake system durability test # 789
Brake becomes mis-
adjusted due to
failure of interface
between brake cable
assy, brake pad assy
and/or wheel assy.
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Excerpted from Effective FMEAs, by Carl S. Carlson,
John Wiley & Sons, © 2012, all rights reserved
TRUNCATED

3. Example FMEA Audit
General Information
 The FMEA team is made up of a bicycle design engineer and a
bicycle test engineer, in support of a new all-terrain bicycle
due to be launched soon.
 The FMEA was completed 4 weeks after design freeze, after
testing had begun.
 The FMEA team prepared for the FMEA project by studying
drawings and sketches for the hand brake subsystem.
 When the FMEA was completed, the bicycle test engineer
thought the result was value added; however the bicycle design
engineer thought the analysis was a waste of time.
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