Contenu connexe Similaire à Six Sigma Primer - Seeking Meaningful Improvments (20) Six Sigma Primer - Seeking Meaningful Improvments1. Six Sigma Primer
Seeking Meaningful Improvements
Presented by: Andy Pattantyus
Prepared for:
APICS Orange County Chapter
by
Strategic Modularity, Inc.
www.strategicmodularity.com
andyp@strategicmodularity.com
Phone: 855-LeanOps FAX: 661-554-0299
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 1 of 40
2. Six Sigma Primer
Learning Objectives
• What is six sigma?
• Are my processes six sigma?
• What is process capability?
• Why care about six sigma?
• How can I get a process to six sigma?
• The six sigma goal: improving yield
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 2 of 40
3. 1. What is Six Sigma?
Overview
• A description of process capability
– Statistical
– Mathematical
• An operational philosophy
– CPI – Continuous Process Improvement
– VR&C – Variability Reduction & Control
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 3 of 40
4. What is Six Sigma?
Definitions - ASQ
• Six Sigma is a philosophy
– This perspective views all work as processes that can be defined,
measured, analyzed, improved and controlled. Processes require inputs (x)
and produce outputs (y). If you control the inputs, you will control the
outputs: This is generally expressed as y = f(x).
• Six Sigma is a set of tools
– The Six Sigma expert uses qualitative and quantitative techniques to drive
process improvement. A few such tools include statistical process control
(SPC), control charts, failure mode and effects analysis and flowcharting.
• Six Sigma is a methodology
– This view of Six Sigma recognizes the underlying and rigorous approach
known as DMAIC (define, measure, analyze, improve and control). DMAIC
defines the steps a Six Sigma practitioner is expected to follow, starting
with identifying the problem and ending with the implementation of long-
lasting solutions. While DMAIC is not the only Six Sigma methodology in
use, it is certainly the most widely adopted and recognized.
Source: ASQ [1]
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 4 of 40
5. What is Six Sigma?
Definitions – Lean Lexicon
• A quality standard of just 3.4 defects per one million
opportunities; 99.9996% perfect.
• Six sigma methodologies emphasize mathematical and
statistical tools to improve the quality of processes that are
already under control.
• Application follows a five-step process of define, measure,
analyze, improve, and control often referred to as DMAIC.
• The term refers to the number of standard deviations a point is
away from the mean point in a bell curve. It often is
represented as 6 sigma.
Source: Lean Lexicon [2]
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 5 of 40
6. What is Six Sigma?
History
• Born at Motorola
– Motorola conceived the six sigma technique in
1986 as a way to achieve the company’s
improvement goals in manufacturing and support
functions.
• Motorola Suppliers – Starting 1991
– Eveready Battery Company Inc. (Energizer)
• Early corporate adopters – Starting 1995
– Allied-Signal (now Honeywell)
– General Electric
– 3M
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 6 of 40
7. What is Six Sigma?
Mathematics or Management?
• Mathematics
– Field of statistics known as Process Capability
– Basis for measurements
– Verifiable data is the basis for decisions
• Management
– Continuous improvement efforts
• Reduce process variation
• Achieve stable and predictable results
– Focus on business and manufacturing processes
– Organizational commitment, especially top-level
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 7 of 40
8. 2. Are my processes six sigma?
Probably Not!
• If your organization knows process
capability, and regularly uses it as a
tool, then you know if your processes
are six sigma.
• Otherwise, most processes which have
not been the object of continuous
process improvement and variability
reduction are likely less than 4 sigma.
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 8 of 40
9. 3. Process Capability
A qualitative definition
• Capable Process - Predictable
– Stays in control w/o intervention
– Get it right the first time
– Process monitoring: Good Process = Good part
– High yield
• Poor Process - Unpredictable
– Out of control - constant intervention required
– High Scrap and/or Lots of rework
– Checking parts instead of monitoring processes
– Low yield
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 9 of 40
10. Process Capability - Cp
A quantitative definition
SpecificationWidth
Cp =
Pr ocessCapab ility
± 4σ ± 6σ
Cp = Cp = 1 .33 Cp = Cp = 2.0
± 3σ ± 3σ
Source: Motorola [4]
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 10 of 40
11. Process Capability
Measurement Methods
• Design of Experiments (DOE)
– Don’t know which variables are important
• Statistical Process Control (SPC)
– Stable process
– Measuring the important variables
• Process Capability (Cp)
– Describes the ratio between process variability and the
upper and lower specification limits.
– Based on normal distribution statistics, which is valid only if
there is no assignable cause variation!
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 11 of 40
12. 4. Process Capability vs. Yield Loss
Why Care About Six Sigma?
• Six Sigma is all about reducing the
cost of waste within the
organization.
• Two primary wastes with high costs
– Yield Loss – translates to high production
costs due to poor efficiency.
– Latent Defects – translates to warranty
costs from defects in the field.
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 12 of 40
13. 4. Process Capability vs. Yield Loss
Three Quick Stories
• Living with Systemic Waste
– The Dumpster “Hall of Shame”
• Living with latent defects
– Hot House Aging
• Living with defects during development
– The “De-Ringer” Department
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 13 of 40
14. Process Capability vs. Yield Loss
Why is Six-Sigma important?
Source: Motorola [4]
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 14 of 40
15. Process Capability vs. Yield Loss
How process shifts affect yield
Source: Motorola [4]
• At low process capability, a process shift
can produce significant yield losses.
• Six-sigma protects against yield losses
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 15 of 40
16. Process Capability vs. Yield Loss
How process shifts affect yield
• Graph shows one
process step
• Process control
– Difficult to keep most
processes centered
– Expect a shift
• Yield Loss = ƒ (Cp)
– For Cp = 1, defect rate
approaches 7%
– For Cp = 2, defect rate is
Source: Motorola [4]
negligible
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 16 of 40
17. Process Capability vs. Yield Loss
Yield measures process efficiency
• Percent Yield: the proportion of useful
output compared to a theoretical
waste-free 100%
• Rolled Yield: the proportion of units
completing a process without defects.
• First Time Yield: The proportion of
units successfully passing an
inspection step the first time.
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 17 of 40
18. Process Capability vs. Yield Loss
Causes of Yield Loss
• Process step is not performed correctly on
some parts, due to process shift caused by
the interaction between:
– inadequate equipment, and
– defective raw material.
• Flawed inspection process, where the
inspection process is prone to:
– type I errors - false rejections, where conforming
items may be incorrectly rejected.
– type-II errors - false acceptance, where non-
conforming items may be incorrectly accepted.
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 18 of 40
19. Process Capability vs. Yield Loss
The Tyranny of Large Numbers
Source: Feiman [5]
• The Math: 0.9 x 0.9 x 0.9 x 0.9 = 0.656
• Imagine a process with hundreds of
steps: Ex. Semiconductor
Manufacturing
• Yield becomes critically important
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 19 of 40
20. Process Capability & Yield Loss
Managing Workflow Complexity
Source: Feiman [5]
• Picture shows a single process step
• Complex material flow paths
• For rejected parts, flow stops while
awaiting a disposition decision
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 20 of 40
21. 5. Getting to Six Sigma
Process Improvement
• Continuous Process Improvement
– TOC – Theory of Constraints
– Lean
– Six Sigma
– TLS – TOC/Lean/SixSigma
• Improvement Cycles
– Measure
– Develop processes to eliminate assignable cause
variations
– Repeat
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 21 of 40
22. Getting to Six Sigma
Tools to Find Assignable Cause
Source: Wordpress [6]
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 22 of 40
23. Getting to Six Sigma
Process Improvement
• Deming formally defined the original
improvement cycle
– PDCA – Plan, Do, Check, Act
• Six Sigma uses two PDCA-based project
methodologies
– DMAIC to improve existing products/processes
• define, measure, analyze, improve, control
– DMADV to develop new products/processes
• define, measure, analyze, design, verify
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 23 of 40
24. Getting to Six Sigma
Plan-Do-Check-Act Improvement Cyclss
Source: Shook [9]
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 24 of 40
25. Getting to Six Sigma
A3 Sheets PDCA Improvement Cycles
The way The better
things way to
happen work.
now.
Do
Plan Check
Act
Source: Sobek [7]
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 25 of 40
26. Getting to Six Sigma
A3 Sheets as a Management Tool
• A3 is the Basis for a results oriented culture
• The point of the A3 is to:
– Communicate
– Gain Consensus
– Solve Problems
– Get Results
• Understanding a new way to work replaces
training a new behavior.
– Existing staff implements a new process
– New staff is oriented to existing process
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 26 of 40
27. 6. Improving Yield - Six Sigma Goal
Do we really need six sigma?
• Go all the way to six sigma? Maybe
• A clear organizational focus on
achieving measurable and quantifiable
returns from each Six Sigma project.
– Weigh the Cost vs. Benefit
• Cost of improvement project
• Benefits from improved yield = reduced costs
– Yield = ƒ (Capability, Number of Steps)
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 27 of 40
28. Improving Yield - Capacity
Capacity Planning and Reporting
• The capacity plan must account for
yield loss throughout the process.
– Material loss - disposition as scrap
– Extra capacity - disposition as rework
• Some ERP systems have provisions
for tracking yield loss and secondary
part flows.
• Some ERP systems have provisions
for producing yield reports
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 28 of 40
29. Improving Yield - Workflow
Managing Yield Loss Complexity
Parts Flow
Parts Flow
10% Bad
10% Bad
Source: Feiman [5]
• Picture shows a single process step
• Complex material flow paths
• For rejected parts, flow stops while
awaiting a disposition decision
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 29 of 40
30. The Tyranny of Large Numbers
Yield = ƒ (Capability, Number of Steps)
• Yield is the result,
dependent on:
– Process capability
– Number of steps
• To improve yield:
– Redesign product to
decrease part count
and improve process.
– Redesign process to
increase Cpk.
Source: Motorola [4]
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 30 of 40
31. Improving Yield – Making the Case
Defining the Project - System
• Analyze Process – Current State VSM
• Conduct Investigations
– Do the Gemba and create A3 sheets
• Design Lean Process – Future State VSM
• Conceptual Design: Several scenarios
– Redesign the product and process - DFMA
– Financial Analysis and Case – A3 sheets
• Propose Project - A3 Sheets (PDCA story)
– Schedule, resources, cost estimate
• Review with management & refine
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 31 of 40
32. Improving Yield - How to Spend?
Product, Process or Capacity?
• Product improvement generates:
– reduced parts count
– simplified manufacturing processes
• Process improvement generates:
– simplified manufacturing processes
– improved process reliability
– predictable capacity plans and schedules
– permanent savings in labor, materials
• Capital Investment in a low yield process
– reduces ROA and ROIC
– “hardtools” inefficiency
– may make sense early in product life cycle or if time to
market is the most important factor
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 32 of 40
33. Improving Yield – Design Work
Approaching 100% Yield - Holy Grail
• Redesign the Product - DFMA
– Design for Manufacturability & Assembly
– Reduce the parts count
– Eliminate process steps
• Redesign the Process - DFMA
– Simple Process – Complex Part
• Metal stamping
– Complex Process – Simple Part
• Multi-shot Injection Molding
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 33 of 40
34. Improving Yield – Best Process
The Ideal Process Step
• Consumes no labor
• Consumes no material
• Requires no management
• Requires no equipment
• Cycle time = 0
• Yield = 100%
The ideal process step is the one that
does not exist!
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 34 of 40
35. Improving Yield – Best Process
Converging on the Ideal Process
• Fewer parts
– Eliminate parts via DFMA for product and
process redesign.
• Fewer process steps
– Eliminate steps via DFMA for product and
process redesign.
• Robust processes tolerate ±1.5σ shift
• Monitor process, not product
• Fewer inspection steps to speed flow
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 35 of 40
36. Improving Yield – Best Process
The Robust Process
• Six Sigma Process Characteristics
– Process mean is 6σ away from USL and LSL
– Tolerates a ±1.5σ shift in process centeredness
– 3.4 Defective Parts per Million Opportunities (DPMO)
Source: Cmglee, Wikimedia Commons [8]
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 36 of 40
37. Six Sigma Primer
Terminology
• A3 – A single sheet of paper • DPMO – Defects per Million
which tells a PDCA story. Opportunities
• CP – Process Capability • LSL – Lower Spec Limit
• CPI – Continuous Process • PDCA – Plan, Do, Check,
Improvement Act cycle
• DFMA – Design for • PPM – Parts per million
Manufacturability and • SPC – Statistical Process
Assembly Control
• DMADV - define, measure, • TOC – Theory of
analyze, design, verify Constraints
• DMAIC – define, measure, • TLS – TOC/Lean/Six Sigma
analyze, improve, control • USL – Upper Spec Limit
• DOE – Design of • VR&C – Variability
Experiments Reduction and Control
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 37 of 40
38. Six Sigma Primer
Bibliography
[1] ASQ, American Society for Quality, http://asq.org
[2] Lean Lexicon, 4th Edition, Lean Enterprise Institute, 2008.
[3] APICS Dictionary, 13th Edition, 2011
[4] ENG 123, “Design for Manufacturability Participant Guide,” Motorola University, 1992
[5] Feiman, Daniel, et.al “THE Book on . . . Business from A to Z: The 260 Most Important
Answers You Need to Know ,” Build It Backwards Publishing, Los Angeles CA, 2011.
[6] Tools for Root Cause Analysis, http://aacesubajou.wordpress.com
[7] Sobek, Durward K. II, and Smalley, Art “Understanding A3 Thinking: A Critical Component
of Toyota’s PDCA Management System,” Productivity Press, www.productivitypress.com ,
2008, ISBN 978-1-56327-360-5
[8] Cmglee, Six Sigma with 1.5 sigma Process shift, Wikimedia Commons
[9] Shook, John, “Managing to Learn,” Lean Enterprise Institute, 2008
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 38 of 40
39. About the Speaker
Andy Pattantyus, CPIM
Andy Pattantyus, CPIM, is founder, owner and President of Strategic Modularity, Inc. (SMI), a
management consulting company serving divisions of large corporations and SMB clients with
annual revenues of $3 to $30 million. Andy is passionate about enabling client companies to
reach their greatest potential by setting goals, preparing plans and eliminating waste.
Andy’s 30 years of experience in designing/integrating modular production systems and
flexible processes, developing new products, processes and machinery, provide him with a
wide base of knowledge on how to eliminate process inefficiencies. Andy solves business
problems by combining technical innovation with strategy, system design, facility design,
human resource management, project management and accounting. A streamlined and
efficient business perspective, with a strong mix of technical skills, enables Andy and his team
to improve a company’s health. In Andy’s roles, achieving results always required significant
planning before execution.
Before founding SMI, Andy managed development projects and material flow as a Senior
Engineering Manager at Eveready Battery Co. Inc. and as a Director at Quallion LLC. Andy
holds 6 patents, a B.S. and an M.S. in Mechanical Engineering from Virginia Tech as well as
an MBA from Case Western Reserve University.
Andy authored chapters about Yield and Quality in the recently released book:
© THE Book… on Business from A to Z: The 260 Most Important Answers You Need to Know
copyrighted 2011 by Daniel Feiman.
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 39 of 40
40. About the Book
THE Book On… BUSINESS from A to Z
Daniel Feiman, MBA, CMC® Nominated for Global eBook of the Year
http://goo.gl/Gjmz8
Managing Director
Build It Backwards(TM)
Success by Choice; Not Chance(SM)
Office: 310.540.6717 Cell:
818.522.2892
Consulting & Training in:
Strategy * Finance * Process
dsfeiman@BuildItBackwards.com
www.BuildItBackwards.com
http://goo.gl/j6F5b
http://goo.gl/TxRuA
May 16, 2012 © Strategic Modularity Inc. 2012 www.strategicmodularity.com Page 40 of 40
Notes de l'éditeur Sobek pg 128 Shook pg 96 The Toyota Way Fieldbook pg 404 Jimmerson pg 35 The Toyota Way Fieldbook pg 401 The Toyota Way Fieldbook pg 408 Jimmerson pg 52