INCOSE Michigan – May Dinner Meeting
Failure Mode & Effect Analysis (FMEA) in Half the Time Howard C Cooper, MS, DFSS-BB May 13th, 2014
Introduction ● Failure Mode & Effects Analysis (FMEA) is an analytical tool and structured method to: – Recognize and evaluate the potential failure of a product/process and its effects – Identify and prioritize actions which could eliminate or reduce the chance of a potential failure – Document the process
Before they are “baked” into a product 2 Approved for Public Release, Distribution Unlimited, LogNo. 2014-07, 26 FEB 14
Common Types of FMEA ● Design FMEA – Identify and mitigate potential design problems early in the design cycle
● Process / Manufacturing FMEA – Improve quality and reliability, during set-up of initial manufacturing process
● Problem Solving / Six Sigma FMEA – Understand failure modes and effects to identify and solve quality or reliability issues
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Where FMEA is Used Common FMEA Usage
Product Definition: Customer Reqmts: Vehicle Tech Specs
Key product characterist ics, Design FMEA
Process Definition: Process Flow Diagram (PFD)
Process Failure Mode Analysis: Process FMEA
Mfg: Control Strategy: Control Plan, Error proofing
Work Instructions & Process Monitoring Six Sigma FMEA
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Prioritize Failure Modes by Risk Priority Number
Example Design FMEA Cause (What Failed)
Item
Local Failure Effect Mode
locked up, or open output driver
Load Controller
Next Level Up Effect
On Vehicle Mission Soldier(s)
SEV
(physical or chemical processes, design defects, quality defects, part misapplication , or other).
1.No provisioning of MRF = 1 - Combat power for vehicle start up Mission Failure on 100% of combat missions. [System Abort (SA)]
FM & Effects of each failure mode 2. No distribution of power to hull and turret systems (SA Example; Generator Controller Dead)
1. Over Voltage, 2. Voltage Transients
MRF = 1 - Combat Mission Failure on 100% of combat missions. [System Abort (SA)]
Load Controller
1. Over Voltage 2. Voltage Transients
Load Controller
Control Module
1.No provisioning of MRF = 1 - Combat power to vehicle start up Mission Failure on 100% of combat missions. [System Abort (SA)]
Items within the system being analyzed ePDCM Failure 2. No distribution of
power to hull and turret systems
MRF = 1 - Combat Mission Failure on 100% of combat missions. [System Abort (SA)]
43v Transients Clamps on all power supply inputs. MIL-STD-1275 Compliant Relay drivers and other higher current loads have transient protectoin. 5 degree C Thermal Margin on PLCMs
3
5
5
1. Over Voltage 2. Voltage Transients
1. Over Voltage 2. Voltage Transients
43v Transients Clamps on all power supply inputs. MIL-STD-1275 Compliant Relay drivers and other higher current loads have transient protectoin. 5 degree C Thermal Margin on PLCMs Transients Clamps on all power supply inputs. MILSTD-1275 Compliant Relay drivers and other higher current loads have transient protectoin. 5 degree C Thermal Margin on PLCMs Transients Clamps on all power supply inputs. MILSTD-1275 Compliant Relay drivers and other higher current loads have transient protectoin.
Field Failure Detection Method 1629a
DVP&R Detection J1739
HALT tests EMI CS-101 & MILPLCM Trip Status STD-1275 Reporting Suseptability PLCM Pass/ Fail Testing Reprting MIL-STD-810g Environmental Life Test
DET
RPN
DFMEA FM Problem Report #
3
45
SPR00004339
3
45
SPR00004339
Relative Occurrence
Root Cause 5
PLCM Fault indicated
OCC
Severity 5
PLCM Fault indicated
Prevention Design Controls J1739
SEV X OCC X DET = (RPN)
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HALT tests EMI CS-101 & MILPLCM Trip Status STD-1275 Reporting Suseptability PLCM Pass/ Fail Testing Reprting MIL-STD-810g Environmental Life Test
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HALT tests EMI CS-101 & MILPDCM Trip Status STD-1275 Reporting Suseptability PDCM Pass/ Fail Testing Reprting MIL-STD-810g Environmental Life Test
2
HALT tests EMI CS-101 & MILPDCM BIT Pass/ STD-1275 Fail Reporting Suseptability Testing
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SPR00004200 3
45
SPR00004200 3
30
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Example Process FMEA
Steps within the process being analyzed
Deteriorated life of part leading to: - Unsatisfactory appearance due to rust through paint over time. - Impaired function of hardware.
RPN
Insufficient chromate coating over specified surface.
Detec
Manual application of chromate conversion coatings on exposed aluminum substrate (to retard corrosion)
Occur
Potential Potential Effect(s) of Failure Mode Failure
3 Visual check each hour 1/shift for film thickness (depth meter) and coverage.
5
75
Spray head clogged - Viscosity too high - Temperature too low - Pressure too low.
2 Visual check each hour 1/shift for film thickness (depth meter) and coverage.
3
30
Spray head deformed due to impact.
2 Visual check each hour 1/shift for film thickness (depth meter) and coverage.
2
20
Spray time insufficient.
1 Operator instructions and lot sampling (10 doors/shift) to check for coverage of critical areas.
2
10
Potential Cause(s)/Mechanism(s) of Failure 3 - Front Door L.H. 5 Manually inserted spray head not inserted far enough. Sev
Item Process Function
Current Process Controls Detection
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Typical FMEA Process 1. Assemble team of people with diverse knowledge of process & product 2. Bound the problem 3. Identify functions 4. Identify potential failure modes 5. Populate FMEA details 6. Prioritize failure modes based on RPN 7. Mitigate failure modes
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Mission to Improve FMEA Development
● Challenge
Current FMEA problems:
Opportunity:
Time consuming
Rapid (> 2x faster)
High rate of missed critical failure modes
Critical failure modes are given top-priority
Ad hoc identification of failure modes
Process-driven identification of all failure modes
Disjointed, undirected timeconsuming discussion
Focused, efficient development effort
Allows prioritization only after FMEA development
Prioritization can happen before FMEA development
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Improved FMEA Process • In 2012, GDLS developed process to prepare ‘efficient’ and ‘effective’ FMEA at greatly reduced time and cost • Process involves four primary tools: Block / Process Diagram
p-Diagram
Decomposition Table
FMEA
Major innovation:
Decomposition Table identifies and prioritizes Failure Modes (FMs) into FMEA. Focuses analysis on critical failure modes Approved for Public Release, Distribution Unlimited, LogNo. 2014-07, 26 FEB 14
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Step 1: Bound the System Boundary Diagram / Process Flow Vehicle Structure
What
Mount
Engine
Seal / Flat Flange
Elbow 90
VBand
Exhaust Brake (valve)
VBand
Flex Pipe
VBand
Muf f ler
Insulation
VBand
Exhaust Pipe
Exhaust Out
Mount
Vehicle Structure
Identifies and verifies: 1. System functions: lines crossing the dotted boundary 2. “Items” within the dotted line system boundary
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Step 2: Characterize the Process P-Diagram
What (From Boundary Diagram)
Why
Green blocks, identify functions of the system (or process) Yellow blocks ~ Noise Factors, Blue block, Control Factors, Pink blocks ~ Error States Approved for Public Release, Distribution Unlimited, LogNo. 2014-07, 26 FEB 14
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Outstanding Problem & Opportunity ● Boundary or Process Flow Diagram – Identifies “Items” for the FMEA, but not the Failure Modes (FM) of those “items”
● P-Diagram – Identifies system functions or requirements (even noise factors) but not the function or FMs of the “items”
● Opportunity – Develop a table that will identify and link “items” to their functions, and to their functional FMs Approved for Public Release, Distribution Unlimited, LogNo. 2014-07, 26 FEB 14
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Step 3: Map Functions to Failure Modes
2. Attenuate NVH
Contain Heat
X X X
X
Secure
Hardware Functions:
Provide Flow
1. Transfer Exaust from Engine out of the Vehicle
3. Limited thermal transfer to vehicle
Contain Exhaust
(Ideal Functions from PDiagram / Functions (lines crossing boundary of B-Diagram "Design".)
Attenuate NVH
System Functions "Design" Functions: P-Diagram
X
X
X X
X
5. Exhaust Brake Engine Slowing
Partially Restrict Exhaust
Function to Hardware Decomposition Table
Hardware:
Boundary / Process Diagram
V-Band Clamps Exaust Pipe Flat Flange Seals Muffler Insulation Isolation Mounts Exaust Brake Flex Pipe Elbow
X X
X X X X
X X X
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X
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Step 3: Map Functions to Failure Modes
2. Attenuate NVH
Contain Heat
X X X
X
Secure
Hardware Functions:
Provide Flow
Need to Identify Item / HW Functions
1. Transfer Exaust from Engine out of the Vehicle
3. Limited thermal transfer to vehicle
Contain Exhaust
(Ideal Functions from PDiagram / Functions (lines crossing boundary of B-Diagram "Design".)
Attenuate NVH
System Functions "Design" Functions: P-Diagram
X
X
X X
X
5. Exhaust Brake Engine Slowing
Partially Restrict Exhaust
Function to Hardware Decomposition Table
Hardware:
Boundary / Process Diagram
V-Band Clamps Exaust Pipe Flat Flange Seals Muffler Insulation Isolation Mounts Exaust Brake Flex Pipe Elbow
X X
X X X X
X X X
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X
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Step 3: Map Functions to Failure Modes
2. Attenuate NVH
Contain Heat
X X X
X
Hardware Functions: Secure
Identify Functions
Provide Flow
1. Transfer Exaust from Engine out of the Vehicle
3. Limited thermal transfer to vehicle
Contain Exhaust
(Ideal Functions from PDiagram / Functions (lines crossing boundary of B-Diagram "Design".)
Attenuate NVH
System Functions "Design" Functions: P-Diagram
X
X
X X
X
5. Exhaust Brake Engine Slowing
Partially Restrict Exhaust
Function to Hardware Decomposition Table
Hardware:
Boundary / Process Diagram
V-Band Clamps Exaust Pipe Flat Flange Seals Muffler Insulation Isolation Mounts Exaust Brake Flex Pipe Elbow
X X
X X X X
X X X
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X
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Step 3: Map Functions to Failure Modes
2. Attenuate NVH
Contain Heat
X X X
X
Hardware Functions: Secure
Identify Functions
Provide Flow
1. Transfer Exaust from Engine out of the Vehicle
3. Limited thermal transfer to vehicle
Contain Exhaust
(Ideal Functions from PDiagram / Functions (lines crossing boundary of B-Diagram "Design".)
Attenuate NVH
System Functions "Design" Functions: P-Diagram
X
X
X X
X
5. Exhaust Brake Engine Slowing
Partially Restrict Exhaust
Function to Hardware Decomposition Table
Hardware:
Boundary / Process Diagram
V-Band Clamps Exaust Pipe Flat Flange Seals Muffler Insulation Isolation Mounts Exaust Brake Flex Pipe Elbow
X X
X X X X
X X X
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X
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Step 3: Map Functions to Failure Modes Function to Hardware Decomposition Table 1. Transfer Exaust from Engine out of the Vehicle
2. Attenuate NVH
3. Limited thermal transfer to vehicle
5. Exhaust Brake Engine Slowing
Contain Heat
Partially Restrict Exhaust
X X X
X
Hardware Functions: Secure
Identify Functions
Provide Flow
(Ideal Functions from PDiagram / Functions (lines crossing boundary of B-Diagram "Design".)
Contain Exhaust
P-Diagram
Attenuate NVH
System Functions "Design" Functions:
X
X
X X
X
Hardware:
Boundary / Process Diagram
V-Band Clamps Exaust Pipe Flat Flange Seals Muffler Insulation Isolation Mounts Exaust Brake Flex Pipe Elbow
X X
X X X X
X X X
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X
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Decomposition Table Structures FMEA Function to Hardware Decomposition Table
Secure
X
X X
X
5. Exhaust Brake Engine Slowing
Partially Restrict Exhaust
“X” indicates a Function (and 4 FMs in the FMEA)
X
2. Attenuate NVH
3. Limited thermal transfer to vehicle
Contain Heat
B-Diagram or Pr-Flow Chart
Provide Flow
Hardware Functions:
3-4 FMs per Function
From
1. Transfer Exaust from Engine out of the Vehicle
Contain Exhaust
functions translate to FMs
(Ideal Functions from PDiagram / Functions (lines crossing boundary of B-Diagram "Design".)
Attenuate NVH
"Design" Functions: System Functions
X X X
X
Hardware: V-Band Clamps Exaust Pipe Flat Flange Seals Muffler Insulation Isolation Mounts Exaust Brake Flex Pipe Elbow
X X
X X X X
X X X
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X
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3 Purposes of the Decomposition Table • Ensures all items are captured into the
FMEA • Ensures multiple function items and their potential failure modes are identified into the FMEA • Provides opportunity to identify and prioritize by criticality of hardware or process functions before populating failure modes into the FMEA Approved for Public Release, Distribution Unlimited, LogNo. 2014-07, 26 FEB 14
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Decomposition Table Prioritizes Functions Function to Hardware Decomposition Table (with Maximum Criticality Scored)
Restrict Exhaust
5 2 2 2 4 1 3 2 2 1
Contain Heat
V-Band Clamps Exaust Pipe Flat Flange Seals Muffler Insulation Isolation Mounts Exaust Brake Flex Pipe Elbow
3 15
Attenuate NVH
Severity:
Provide Flow
Hardware:
2. Attenuate NVH
5. Exhaust Brake Engine Slowing
Contain Exhaust
Hardware Functions:
1. Transfer Exaust from Engine out of the Vehicle
3. Limited thermal transfer to vehicle
Secure
(Ideal Functions from PDiagram / Functions (lines crossing boundary of B-Diagram "Design".)
Likelyhood of Failure: 1 - 5
System Functions: "Design"
5
3
3
3
3
10
6
Criticality # rather than “X”
6 10 20
12
9 10 10 5
12 3 9
3
6 6 3
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Preparation Flow into Decomp Table
Function to Hardware Decomposition Table (with Maximum Criticality Scored)
Engine
Seal / Flat Flange
Elbow 90
VBand
Exhaust Brake (valve)
VBand
Flex Pipe
VBand
Muf f ler
Insulation
VBand
Exhaust Pipe
Exhaust Out
3 15
5 10
6
10 20
12
Restrict Exhaust
Mount
5 2 2 2 4 1 3 2 2 1
Contain Heat
Vehicle Structure
Severity:
V-Band Clamps Exaust Pipe Flat Flange Seals Muffler Insulation Isolation Mounts Exaust Brake Flex Pipe Elbow
5. Exhaust Brake Engine Slowing
Attenuate NVH
Hardware:
3. Limited thermal transfer to vehicle
Provide Flow
1. P-Diagram Ideal Functions – to Design Functions in F-H Decomp.
2. Attenuate NVH
Contain Exhaust
Hardware Functions:
1. Transfer Exaust from Engine out of the Vehicle
Secure
(Ideal Functions from PDiagram / Functions (lines crossing boundary of B-Diagram "Design".)
Likelyhood of Failure: 1 - 5
"Design" System Functions:
3
3
3
3
12 3 9
3
6
9 10 10 5
6 6 3
6
Mount
Vehicle Structure
2. B-Diagram or Process Flow inner blocks go to Decomp. Table
3. Identify all ‘Item’ Functions needed to accomplish each System Function 4. Mark with an “X” or with a “Criticality #”
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Step 4: Use Decomp Table to Fill FMEA Function to Hardware Decomposition Table (with Maximum Criticality Scored)
1
1 Function (measurable output, design requirement)
3 15
5 10
6
10 20
12
Restrict Exhaust
5 2 2 2 4 1 3 2 2 1
33
Contain Heat
22
5. Exhaust Brake Engine Slowing
Attenuate NVH
Severity:
V-Band Clamps Exaust Pipe Flat Flange Seals Muffler Insulation Isolation Mounts Exaust Brake Flex Pipe Elbow
3. Limited thermal transfer to vehicle
Provide Flow
Hardware:
2. Attenuate NVH
1 Contain Exhaust
Hardware Functions:
1. Transfer Exaust from Engine out of the Vehicle
Secure
(Ideal Functions from PDiagram / Functions (lines crossing boundary of B-Diagram "Design".)
Likelyhood of Failure: 1 - 5
"Design" System Functions:
3
3
3
3
12 3 9
3
1
4
6
9 10 10 5
2
Item
1. Transfer Exaust from Engine out of the Vehicle V-Band Clamps
6 6 3
6
3
Potential Failure Mode
Local Effect Exhaust leak
4
Next Level Up Effect
Loss of 1. Transfering Exhaust from Engine to out-side the Vehicle
Loss of Securing Partial Securing Intermittent Securing
FMEA filled in from F-H Decomp Table
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Benefits of Improved FMEA Development Pareto Chart (80/20 Rule)
Four Step FMEA Process: ● Organizes and speeds FMEA failure mode identification ● Ensures all hardware-functions and FMs are identified ● Prioritizes critical hardware-functions for FMEA analysis ● Provides power of 80/20 Rule on FMs for best Reliability Growth ● Focuses attention and time on mitigation of “significant few” (the most critical failure modes (FMs)
F-H Decomp Table now being used on multiple GDLS Contracts: for DFR, to facilitate earlier diagnostics planning, to meet Weight and Testability Requirements Addressing most critical FMs yields greatest reliability growth.
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Cost Savings Attributed to New Process Savings Calculation
Before vs, After Facilitator Cost
(savings to GDLS)
Previous Programs doing DFMEA without 'F-H Decomp' Start SFR
FCS 01-Mar-06 Stryker-SMOD 01-Jan-10 Average:
End PDR 15-Dec-09 15-Dec-10
Weeks 185 50 117.5
Rel-Heads Hrs/Week Total Hrs. $Rate/Hr. Total $ 3 35 19,425 $77 $1,495,725 4 35 7,000 $77 $539,000 3.5 Average: $1,017,363
2013 Programs using 'F-H Docomp Tool/Method' for DFMEA Start SFR
End PDR
Weeks
Stryker+Tr 16-Oct-12 Stryker-ECP 01-Oct-12 Abrams ECP1 04-Feb-13 Average:
15-Mar-13
20
1
35
700
$77
$53,900
27-Sep-13
50
0.65
35
1,138
$77
$87,588
14-Aug-13
27.3
1
35
956
$77
$73,574
32.43
0.88
931
$77
$71,687
Facilitator Savings X 3 for FMEA Team, X 3 Programs in 2013 = Total Savings
Rel-Heads Hrs/Week Total Hrs. $Rate/Hr.
Savings on Facilitator Cost
Total $
Savings $1,424,038 Savings over FCS - DFMEA Facilitator $467,313 Savings over SMOD - DFMEA Facilitator $945,676 Savings over FCS & SMOD Average, for DFMEA Facilitator X3 Facilitator labor Savings over SMOD baseline, for DFMEA Team (3-8) $1,401,939 Average 2013 FH-Decomp Program Savings over SMOD baseline - DFMEA Cost X3 Three 2013 Programs: Stryker+Tr, Stryker-ECP and Abrams ECP1 $4,205,817 Total 2013 Savings from using FH-Decomp to prepare DFMEA
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Questions?
Presenters: Howard C Cooper, MS, DFSS-BB DFR Reliability Engineer
[email protected]
Mark Petrotta, MS, DFSS-MBB Engineering Process Excellence
[email protected]
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