2. 6 Overview Six Sigma:
- A Definition
- Applied to GE
- GE Quality Initiative
- Why This Approach?
- Origin of Six Sigma
- The “Breakthrough Strategy”
- Arriving at Sigma
Six Sigma Structure
Key Concepts & Tools
A Practical ExampleAn Overview....Not a lot of Details!!
3. 6 Overview “Six Sigma” If we can’t express what we know in the form of numbers,
we really don’t know much about it.
If we don’t know much about it, we can’t control it.
If we can’t control it, we are at the mercy of chance. Mikel J. Harry
President & CEO
Six Sigma Academy, Inc.A Rigorous Method for Measuring & Controlling Our Quality
“...will bring GE to a whole new level of quality in a fraction of the
time it would have taken to climb the learning curve on our own.”John F. Welch, Jr.
1995 GE Annual Report
4. 6 Overview What Does “Sigma” Mean? Sigma is a Measure of the Consistency of a ProcessIt (is Also the 18th Letter in the Greek Alphabet!
5. Why Does GE Need A Quality Initiative?GE Raising The Bar
New Goal to be “Best in the World” vs. #1 or #2
Customers are Expecting More, we Must Deliver
“Ship-and-fix” Approach no Longer Tolerated in the Market
Aim to Speed Past Traditional Competitors in 5 Years
Goal Consistent with Reduced Total Costs
We Must Acknowledge Our Vulnerabilities
Poor Quality That Impacts Customers
Problems with NPI
Too High Internal Costs6 Overview We Need a Major Initiative to Move From
Where we Are to Where we Want to be
6. 6 Overview Why Does GE Need A Quality Initiative?40%35%30%25%20%10%15% 5%Cost of Failure (% of Sales)Defects per Million3.4233621066,807308,537500,000Sigma654321 Estimated Cost of Failure in US Industry is 15% of Sales; Taking
GE From a 3 to a 6 Company Will Save ~ $10.5 Billion per Year!
7. Why “Six Sigma”?Proven Successful in “Quality-Demanding” Industries e.g.,
Motorola, Texas Instruments (many process steps in series)
Proven Method to Reduce Costs
Highly Quantitative Method – Science and Logic Instead of Gut Feel
Includes Manufacturing & Service (close to customer) and Provides Bridge to Design for Quality Concepts
Has Support and Commitment of Top ManagementIt Works!!!
8. 6 Overview Sigma3456SpellingMoneyTime1.5 Misspelled Words
per Page in a Book1 Misspelled Word
per 30 Pages in a Book1 Misspelled Word in
a set of Encyclopedias1 Misspelled Word in all
of the Books in a Small
Library$2.7 Million Indebtedness
per $1 Billion in Assets$570 Indebtedness
per $1 Billion in Assets$63,000 Indebtedness
per $1 Billion in Assets$2 Indebtedness
per $1 Billion in Assets3 1/2 Months
per Century2 1/2 Days
per Century30 Minutes
per Century6 Seconds
per Century6 is Several Orders of Magnitude Better Than 3!!!Sigma: A Measure of Quality
9. 6 Overview Where Does “Six Sigma” Come From? Mikel J. Harry one of the Original Architects
Previously Headed Quality Function at ABB and Motorola
Now President/CEO of Six Sigma Academy in Phoenix, Arizona
Has Consulted for Texas Instruments, Allied Signal (and others)
Currently Retained by GE to Teach the Implementation,
Deployment and Application of Six Sigma Concepts & Tools Learning from Those Who Have had Success
With 6Will Accelerate its Implementation at GE
10. 6 Overview So...What is Six Sigma? A Measurement System A Problem-Solving Approach A Disciplined Change Process“THE SIX SIGMA BREAKTHROUGH STRATEGY”MeasureAnalyzeImproveControl
11. 6 Overview How Do We Arrive at Sigma?Measuring & Eliminating Defects is the “Core” of Six SigmaMeasurement SystemIdentify the CTQsLook for Defects
in Products or
Services “Critical to Quality”
Characteristics or
the Customer
Requirements for a
Product or Service Count Defects
or failures to
meet CTQ
requirements in
all process steps Define Defect
Opportunities Any step in the
process where a
Defect could occur
in a CTQ Arrive at DPMO Use the SIGMA
TABLEConvert DPMO to
Sigma Defects Per Million
Opportunities2
3
4
5
6308,537
66,807
6,210
233
3.4PPM Defects per
Million of
Opportunity Sigma
Level
12. 6 Overview Measurement System2
3
4
5
6308,537
66,807
6,210
233
3.4PPM SIGMA
LEVEL DEFECTS per
MILLION
OPPORTUNITYIRS Tax AdviceBest CompaniesAirline SafetyAverage CompanyGEAirline BaggageDoctor’s PrescriptionRestaurant BillsAverage Company in 3 to 4Range Some Sigma “Benchmarks”
13. 6 Overview Measurement SystemA Graphic/Quantitative Perspective on VariationAverage ValueMany Data Sets Have a Normal or Bell ShapeNumber of
People
Arriving
at CRDTime7:00 7:15 7:30 7:45 8:00 8:15 8:30 8:45 9:00 9:15
14. 6 Overview Problem Solving ApproachCenter
ProcessReduce
SpreadXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXOff-TargetUnpredictableOn-Target 6Helps us Identify and Reduce VARIATION due to:
- Insufficient Process Capability
- Unstable Parts & Materials
- Inadequate Design Margin
15. TargetUSLLSLTargetUSLLSLTargetUSLLSLCenter
ProcessReduce
SpreadOff-TargetUnpredictableOn-TargetDefects6 Overview Problem Solving Approach“Lower Specification Limit” “Upper Specification Limit”Less Variation Means Fewer Defects & Higher Process Yields
16. 6 Overview Problem Solving ApproachKey Components of “BREAKTHROUGH STRATEGY”MeasureAnalyzeImproveControl Identify CTQ &
CTP (Critical to
Process) Variables
Do Process
Mapping
Develop and
Validate Measurement
Systems Benchmark and
Baseline Processes
Calculate Yield
and Sigma
Target Opportunities
and Establish
Improvement Goals
Use of Pareto Chart
& Fishbone Diagrams Use Design of
Experiments
Isolate the
“Vital Few” from the
“Trivial Many”
Sources of Variation
Test for Improvement
in Centering
Use of Brainstorming
and Action Workouts
Set up Control
Mechanisms
Monitor Process
Variation
Maintain “In Control”
Processes
Use of Control
Charts and
Procedures A Mix of Concepts and Tools Will Also Integrate with NPI Process
17. 6 Overview Disciplined Change ProcessA New Set of QUALITY MEASURES Customer Satisfaction
Cost of Poor Quality
Supplier Quality
Internal Performance
Design for Manufacturability Will Apply to Manufacturing & Non-Manufacturing
Processes and be Tracked & Reported by Each Business
18. 6 Overview StructureQuality Council Members: Labs & Functions
“Pipeline” & BB Project Priorities
Training & Certification
Measurements & Rewards
CommunicationsChampions Leadership: Overall Initiative
Project Funding
HR: Training & RewardsBlack Belts Lead 6 Project Teams
“Measure/Analyze”
“Improve/Control”
Out with Businesses
Here at CRDMaster Black Belts Teach 6
Mentor Black Belts
Monitor BB Projects
Work “Pipeline” Projects
A Resource PoolTeam Members Learn/Use 6 Tools
Work on BB Projects
Part of The Job
Out with Businesses 6 Projects with the GE Businesses
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21. Tabulation of GE Six Sigma Results
22. Benefit Target & UpdateCurrent benefits level @ 10.865 MMQPID loading :
Carryover from 1999 : 4.059
Completed Projects 2000 : 3.313
Active Projects 2000 : 3.285
Total : 10.865 MM
23. (本页无文本内容)
24. Key Concepts & Tools
6 Overview
25. 6 Overview Changing Focus From Output to Process Y
Dependent
Output Effect
Symptom
Monitor X1. . . XN
Independent
Input-Process Cause
Problem
Control Identifying and Fixing Root Causes
Will Help us Obtain the Desired Outputf (X)Y =
26. Process Capability6 Overview Sustained Capability
of the
Process
(long term)USLTTime 1Time 2Time 3Time 4Inherent Capability
of the
Process
(short term)LSLTargetOver Time, a “Typical” Process Will Shift and Drift by Approximately 1.5
27. 6 Overview “Short Term Centered” versus “Long Term Shifted”Six Sigma CenteredLSLUSLT Process
CapabilitySHORT
TERM.001 ppm.001 ppm+6 LONG
TERMLSLUSLT3.4 ppmSix Sigma Shifted 1.5 Process
CapabilityHigher Defect Yield in Long Term Process Capability than Short Term Process Capability -6 4.5 1.5
28. 6 Overview Tying it All TogethershiftCDAB0.5
1.0
1.5
2.0
2.51 2 3 4 5 6C
O
N
T
R
O
LPOORGOODTECHNOLOGYPOORGOODABCD Good Control/
Poor TechnologyPoor Control/Poor
TechnologyPoor Control/
Good Technology WORLD CLASS!!!short termProblem Could be Control, Technology or Both
29. 6 Overview Short Term CapabilityShort Term Capability Ratio(Cp)Cp =LSL-6USLExampleUSLLSL 3.0==-3.063.0-( - 3.0Cp =Cp =1LSLUSL2.5 0.53.0Process MeanTTargetA 3 ProcessThe Potential Performance of a Process, if it Were on Target
30. 6 Overview Long Term Capability (Cpk)CpCpk=Long Term Capability RatioExampleCp =1 (previous chart)Target = -0.5 =0Cpk1 - (-0.5-03 =Cpk =0.83-Off-Target Penalty Target - 3The Potential Performance of a Process, Corrected for an Off-Target MeanLSLUSL2.5 0.53.0Process MeanTTargetA 3 Process
31. 6 Overview Z - Scale of MeasureZ =A Unit of Measure Equivalent
to the Number of Standard
Deviations that a Value is Away
from the Target Value-3.0-0.53.0Z - Values USLLSL2.50.53.0= Process MeanZ TTarget 0A 3 Process
32. The Definitions of YieldFinal Test
Process(Process 4)PassProcess 3Process 1Process 2100(Units Tested) 65 70 8291Yield 1Yield 2Yield 3 Loss 1 Loss 3Rejects Loss 2 9 9 125 First Time Yield (Yft)=Units PassedUnits Tested= 65 70=0.93 Rolled Thruput Yield (Yrt)=(Yield 1)(Yield 2)(Yield 3) . . . . = 91 82 65 70(((())))=0.65100 91 70 82 Normalized Yield (Ynm)==1/n(Yrt)(0.65)1/4=0.89( n: Total Number of Processes ) 6 Overview Yield Exclusive
of ReworkProbability of
Zero DefectsAverage Yield
of All Processes
33. 6 Overview The Impact of ComplexityThe Impact of ComplexityRolledRolled Yield YieldNumber of OperationsNumber of Operations1.001.000.900.900.800.800.700.700.600.600.500.500.400.400.300.300.200.200.100.100.000.00 1 10 100 1,000 10,000 100.000 1,000,000 1 10 100 1,000 10,000 100.000 1,000,000Process Mean Centered on Each OperationProcess Mean Centered on Each Operation 1 10 100 1,000 10,000 100.000 1,000,000 1 10 100 1,000 10,000 100.000 1,000,000RolledRolled Yield YieldNumber of OperationsNumber of Operations1.001.000.900.900.800.800.700.700.600.600.500.500.400.400.300.300.200.200.100.100.000.00 As the Number of Operations Increases, a High
Rolled Yield Requires a High for Each Operation 5 4 3 6 6 5 4 3Process Mean Shifted 1.5at Each Operation
34. 6 Overview Baselining & Benchmarking an Existing Processp (x)DefectsBenchmarkBaseline Entitlement Benchmark.....A World-Class Performance Entitlement.....Achievable Performance Given
the Investments Already Made Baseline.....The Current Level of PerformanceBaselining = Current Process / Benchmarking = Ultimate Goal
35. Some Basic 6-Related Tools6 Overview Scatter Diagram Over Slept Car Would
Not StartWeather Family
ProblemsOtherPareto Diagram Frequency
of
OccurenceReasons for Being Late for WorkArrival
Time
at WorkTime Alarm Went Off
36. MaterialsPeopleThe HistogramControl Charts---------------------------------------------6 Overview Some Basic 6-Related ToolsThe Fishbone DiagramMeasurementsMethodsTechnologyStatementCause & EffectBeing
Late
for
WorkPlot of Daily Arrival Time 9:157:00 7:15 7:30 7:45 8:00 8:15 8:30 8:45 9:00Average ValueNumber
of
People
Arriving
at CRDTime
37. 6 Overview LCLUCLRange ChartROut of Control ConditionLCLXUCLX Bar ChartSome Basic 6-Related ToolsLCL = Lower Control LimitUCL = Upper Control LimitX = MeanR= Average RangeMonitors Changes in Average or Variation Over Time
38. Design of Experiments6 Overview SCREENINGOPTIMIZATIONCHARACTERIZATION For Experiments
Involving a Large
Number of Factors
Useful in Isolating
the “Vital Few “ from
the “Trivial Many” For Experiments
Involving a Relatively
Small Number of Factors
Useful When Studying
Relatively Uncomplicated
Effects & Interactions For Experiments
Involving Only 2
or 3 Factors
Useful When Studying
Highly Complicated
Effects & RelationshipsDOE is More Effective Than Testing One Factor at a Time
39. 6 Overview Using the “One Factor at a Time” Approach Reduce Commute to Work
to 15 Minutes (without
working an abnormal
work schedule) The GoalThe Variables Time of Departure from
Home & Route Taken
to WorkThe Approach Try 3 Potential Routes at Current
Departure Time (7:45), Select
the Best & Vary the Departure
Time ‘til we get to 15 MinutesTime of Departure3
2
17:157:307:458:008:15RouteCombination
SelectedThe ResultUse Route 2 and
Leave at 7:15 to Reach Goal
40. 6 Overview Using “Design of Experiments” (DOE)Time of DepartureDOE (i) Better Accounts for Interactive Variables Missed by “One Factor at a Time”, and (ii) Efficiently Searches for “Sweet Spot” in Parameter SpaceThe Variables Time of Departure from
Home & Route Taken
to WorkThe Approach Vary time of Departure and
Route Simultaneously, in a
Systematic FashionThe ResultA Better Combination Allowing 15 More Minutes of Sleep!!!Actual Commuting Time Averages
(minutes)3
2
17:157:307:458:008:15Route17 20 23 21 1915 18 20 19 1612 15 21 20 18 Original
Conclusion Best
Combination
“Sweet Spot” Reduce Commute to Work
to 15 Minutes (without
working an abnormal
work schedule) The Goal
41. A Practical Example
(The “Cookbook”)6 Overview
42. 6.....and Baking BreadYEAST FLOURUsing a 12 Step Process6 Overview The “BETTER BREAD” Company
43. Step 1.....Selecting “Critical to Quality” (CTQs or Y)What is Important to the Customer?
Rise
Texture
Smell
Freshness
TasteY = Taste!!6 Overview Measure
44. Step 2.....Defining Performance Standards for CTQs or Y6 Overview How Could We Measure Taste (Y)?
Panel of Tasters
Rating System
of 1 to 10
Target: Average
Rating at 8
Desired: No
Individual Ratings
(“defects”) Below 7
Y = 1 2 3 4 5 6 7 8 9 10 TargetDefectsWorstBestBut.....Is this the Right System?Measure
45. 6 Overview Step 3.....Validating the Measurement System for YHow Could We Approach This?
Blindfolded Panel Rates
Several Loaf Samples
Put “Repeat” Pieces
from Same Loaf in
Different Samples
Consistent Ratings* on
Pieces from Same
Loaf = “Repeatability”
Consistent Ratings* on
Samples Across the
Panel = “Reproducibility”
“Repeatability” &“Reproducibility” Suggest Valid Measurement Approach Panel
Member Loaf 1 Loaf 2 Loaf 3 A 5 8 9
B 4 9 1
C 4 9 2
D 8 9 8
E 4 8 2
F 5 9 1
G 8 9 2* Within One Taste UnitMeasure
46. 6 Overview Step 4.....Establish Product Capability for Y (Taste)This is a 3 Process!7 Defects (ratings below 7)24 Ratings (from our panel)=.292292,000 Defects per
1,ooo,ooo LoavesOR7
6
5
4
3
2
11 2 3 4 5 6 7 8 9 10 # of
RatingsRating64321143Defects <7Target = 8AnalyzeHow Do We Approach This?
Bake Several Loaves
Under “Normal”
Conditions
Have Taster Panel
Again Do the Rating
Average Rating is 7.4
But Variation is
too Great for a 6 Process3 x 10 + 4 x 9 + 6 x 8 + 4 x 7 + 3 x 6 + 2 x 5 + 1 x 4 + 1 x 31 + 1 + 2 + 3 + 4 + 6 + 4 + 3
48. 6 Overview Step 6.....Identify Sources of Variation in Y (Taste)How do we Determine the Potential Sources of Variation (Xs)?
Have the Chefs Brainstorm
Some Likely Ones Might be:
- Amount of Salt Used
- Brand of Flour
- Baking Time
- Baking Temperature
- Brand of Yeast
YEAST FLOURMultiple Sources: Chefs, Suppliers, ControlsAnalyze
49. 6 Overview Step 7.....Screen Potential Causes of Variation (Xs)How do we Screen for Causes of Variation (Xs)?
Design an Experiment
Use Different Sources
of Potential Variation
Have Panel Rate
the Bread Used in
the Experiment
Results Lead to the
“Vital Few” CausesYEAST FLOURSourceConclusionNegligibleMajor CauseNegligibleMajor CauseNegligibleFocus on The “Vital Few”Improve
50. 6 Overview Step 8.....Discover Variable Relationships Between “Vital Few” (Xs) and YHow do we Find the Relationship Between the “Vital Few” (Xs) and Taste (Y)?
Conduct a More Detailed Experiment
Focus: Oven Temperature from 325
to 375 and 3 Brands of Flour
RUN# TEMP BRAND
1 325 A
2 325 B
3 325 C
4 350 A
5 350 B
6 350 C
7 375 A
8 375 B
9 375 C FLOUR FLOUR FLOURBrand ABrand BBrand CImproveResults: 350 & Brand A is Best Combination of Temperature & FlourNote: Time is a Factor
Only if Temperature
Changes Significantly
51. 6 Overview Step 9.....Establish Tolerances on “Vital Few” (Xs)How do we Ensure Oven Temperature is Controlled?
Data Suggests 350 ( 5 )
is best Temperature to
Reduce Taste Variation
Brand A Flour to be
Used Except in Case
of Emergency
“BETTER BREAD”
to Search for Better
Alternative Supplier
of Flour Just in Case FLOURBrand ABut.....Is Our Measurement System Correct?Improve
52. 6 Overview Step 10.....Validate the Measurement System for XsHow Could We Approach This?
Need to Verify the
Accuracy of Our
Temperature Gauges
Need for “Benchmark”
Instrumentation for
Comparison
Rent Some Other
“High End” Gauges
Compare the ResultsVerify that our Instruments are AccurateControl
53. 6 Overview Step 11.....Determine Ability to Control Vital Few XsHow Could We Approach This?
Check A Number
of Ovens
Monitor Temperatures
Over Time
Focus on the
Process Capability
Look for Degree of
VariationVariation OK But...Average is High (and the algorithm should be checked)30345 # of
OvensTemperature34635734734834935035135235335435535625201510 5Control
54. 6 Overview Step 12.....Implement Process Control System on XsWhat do we do Going Forward?
Check Ovens Daily
for Temperature Levels
Audit Usage Frequency
of Alternative Flour
Supplier (e.g., Brand C)
Periodically Reassemble
the Panel to Test Taste
Chart the ResultsAnd.....Plot the Data Over Time FLOUR“Brand C”354
353
352
351
350
349
348 1 3 5 7 9 11 13 15 17 19 21 23 25Control