II. Improving Processes
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
II. Improving Processes

Quality Control
– Inspection
– SPC
– Capability Analysis

Total Quality Management (TQM) or
Continuous Quality Improvement (CQI)
–
–
–
–
Fishbone Diagrams
Pareto Analysis
Scatter Plots
Check Sheets
Business Process Reengineering (BPR)
 Van Bennekom, Great Brook, 2003
© Fred
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Learning or Experience Curve
Cost
per
Unit
The cost of a unit after cumulative output
doubles, compared to the prior cost per unit.
E.g., 70% learning curve indicates
the cost per unit decreases by 30%
with each cumulative doubling.
Px
P2x
x
2x
4x
Cumulative Number of Units from Plant
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Sources of Learning

Individual
– The worker naturally gets better at a task
– Plateau effect

Organizational
–
–
–
–

Developing better processes
Improving technology & equipment
Working with suppliers
Working with customers
Learning doesn’t “just happen”
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Improving the “Factory”

Factory as Laboratory
– Performing R&D in the Manufacturing Plant
– Chaparral Steel
• Leonard-Barton, Dorothy, “The Factory as a
Learning Laboratory,” Sloan Management Review,
Fall 1992, pp. 23-38.

The Service Factory
– Incorporating Service Attributes into the Factory
– Inviting Customer to the Factory

The Exchange of Ideas
– Services learning efficiency from Manufacturing
Slide ‹#›
© Fred Van Bennekom, Great Brook, 2003
Stages of Knowledge of
Process & Quality Control









None – ignorance
Know a good outcome from bad
Know the characteristics that describe a quality
outcome
Prioritization of these quality characteristics
Know the variables that lead to these outcomes
Know the impact of individual variables
Know the interaction effects among variables
Able to measure the variables
Able to control process to achieve quality
outcomes – repeatedly & consistently
© Fred Van Bennekom, Great Brook, 2003
Art
Science
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Quality Assurance —
When to Inspect?
INPUT
RAW MATERIALS
PURCHASED PARTS
PROCESS
BEFORE A COSTLY OPERATION
BEFORE A COVERING OR
CLOSING OPERATION
BEFORE AN IRREVERSIBLE
PROCESS
© Fred Van Bennekom, Great Brook, 2003
OUTPUT
FINISHED GOODS
Slide ‹#›
Quality Assurance
Achieved through
Cost
– Inspection
• 100% inspection, sampling
inspection
– Process Control
Total Cost
Cost of Inspection
Cost of passing Defects
Optimum
Amount of Inspection
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Competing Quality Control
Concepts

Inspect quality in
–
–
–
–
–

Acceptable Quality Levels (AQLs)
Sample from a Lot
Decision Rule: if X are good, accept the Lot
Used both for outgoing and incoming testing
Philosophy: It’s okay to ship s***
Build quality in
– Statistical Quality Control (SPC)
– Inherent Capability Analysis
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Inherent Capability Analysis

Determine the inherent capability of the process to
produce goods at some quality level.
– Gather historical data on a process
– If most output (+/-3s) falls within Design Specs, then
process is capable
– Six-Sigma Quality Level: when 12s output
(+/- 6s) falls within Design Specs
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Six Sigma Philosophy

Goal: reduce variability in a process to the point
where the resulting product becomes more
– Robust in use (good for the customer)
– Easier to design because parts can be “spec’d” to
tighter tolerance
– Less expensive to manufacture due to lower quality
failures (also good for the customer!)

Quality Level at 6 sigma
– 3.4 defects per million opportunities
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Six Sigma

The Philosophy
–
–
–
–
–

Build to Customer Critical To Quality (CTO) criteria
Fact-driven, measurement-based
Structured problem solving approach
Define, Measure, Analyze, Improve, Control (DMAIC)
Improvement projects become part of everyone’s job
The Players
– Champions: Manager in the project area
– Master Black Belts: Mentors the project teams
– Black Belts: Full time team leader, trainer, facilitator
– Bennekom,
Green Belts:
Team
© Fred Van
Great Brook,
2003 members
Slide ‹#›
Statistical Process Control
Capable processes also must be controlled
 SPC distinguishes 2 types of variability

– Normal (Random) variability
– Abnormal (Structural) variability

How to apply SPC
– Construct charts (and update occasionally!)
– Collect data regularly – sampling plan
– Observations outside of limits indicate the process
potential is “out of control”- statistically
– Find “assignable causes”
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Developing Control Charts







Identify the process you want to study
Check whether the process is running OK
Take sample outputs at some fixed intervals
For each sample - calculate the Average and the Range
After taking sufficient samples,
Calculate the average of the sample averages, and of the
ranges
Calculate the Std. Dev.s for both.
Set the UCL (Upper Control Limit) at Average + 3*Std.Dev.
Set the LCL (Lower Control Limit) at Average - 3*Std. Dev.
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Control Charts



Variable Control Chart (assumes normal distribution)
Range Chart
p - chart
– also known as fraction defective chart (assumes binomial
distribution)
– s.d. = SQRT(f.d.*(1 - f.d.)/n) {f.d. = fraction defective}

c - chart
– also known as defective chart (assumes Poisson distribution)
– s.d. = SQRT(mean)
For any control chart:
 UCL (Upper Control Limit) = mean + z*s.d.
 LCL (Lower Control Limit) = mean - z*s.d.
where z is set to reflect the assurance that the process is in control.
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Statistical Process
Control Charts
x
x
x
x
x
x
Center line
x
x
1
Upper Control Limit
Lower Control Limit
2
3
4
5
6
7
8
Observation Block
© Fred Van Bennekom, Great Brook, 2003
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SPC – Types of Measures

Attributes
– Physical measures: weight, height, size

Characteristics
– Proportion defective
© Fred Van Bennekom, Great Brook, 2003
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TQM Defined

American Society of Quality Control
– Simply put, TQM is a management approach to long
term success through customer satisfaction
– TQM is based on the participation of all members of an
organization in improving processes, products, services,
and the culture they work in.
– TQM benefits all organization members and society.
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
The Start of TQM...

Everything started by Walter Shewhart
– Bell Labs in the 1920s
– Developed the concept of Statistical Process
Control
– Two young scientists working with him:
• W. Edwards Deming
• Joseph Juran
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
W. Edwards Deming
 Key Arguments
– The basic cause of sickness in American industry and
resulting unemployment is failure of top management to
manage.
– Everyone doing his[/her] best is not the answer. It is
necessary that people know what to do.
– Drastic change is required. The responsibility for
change rests on management. The first step is in
learning how to change.
– Quality and productivity are not to be traded off
against each other.
– Bennekom,
Productivity
is a2003
by-product of quality and of doing
the
© Fred Van
Great Brook,
Slide
‹#›
W. Edwards Deming’s
Fourteen Points
1.
2.
3.
4.
5.
Create constancy of purpose
Adopt the new philosophy
Cease dependence on mass inspection
Don’t award business on price tag alone
Improve constantly the system of production and
service
6. Institute training
7. Institute leadership
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
W. Edwards Deming’s
Fourteen Points
8. Drive out fear
9. Break down barriers between staff areas
10. Eliminate slogans, exhortations, and targets for
the workforce
11. Eliminate numerical quotas
12. Remove barriers to pride of workmanship
13. Institute a vigorous program of education and
retraining
14. Take action to accomplish the transformation
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Deming’s Seven Deadly Diseases
1. Lack of constancy of purpose
2. Emphasis on short-term profits
3. Evaluation by performance rating, merit rating,
or annual performance review
4. Mobility of management
5. Running a company on visible figures alone
6. Excessive medical costs
7. Excessive costs of warranty, fueled by lawyers
that work on contingency
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Quality Management
CONTINUOUS IMPROVEMENT - THE DEMING WHEEL
PLAN
IDENTIFY AND ANALYZE THE PROBLEM
DATA COLLECTION
PARETO ANALYSIS
FLOW CHARTS
CAUSE AND EFFECT DIAGRAMS
CONTROL CHARTS
ACT
DO
IMPLEMENT CHANGES
ON A SMALL SCALE
DOCUMENT CHANGES
IMPLEMENT IN REST OF
THE ORGANIZATION
CHECK
EVALUATE NEW DATA
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Joseph Juran
The users of a product or service should be able to
count on it to do what it’s supposed to do!
 Five dimensions of Fitness for Use

–
–
–
–
–

Quality of Design
Quality of Conformance
Availability
Safety
Field Use
Costs of Quality
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Quality Dimensions

Design Quality
– Characteristics of the product’s original design

Conformance Quality
– Building products (or delivering services) to the
specifications of the product designers
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Costs of Quality
Prevention
 Appraisal
 Internal Failures
 External Failures

© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
More Gurus
Crosby - Quality is Free
 Feigenbaum - Total Quality Control (1954)
 Taguchi - Robust Manufacturing
 Ishikawa - Total Quality Control the Japanese Way

© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Taguchi’s Quality Imperatives
Quality losses are mainly external product failure
 Robustness results primarily from product design
 Robust products have strong signal-to-noise ratio
 Use experimental design to test component part
interaction effects
 Quality Loss Function: square of deviation from target
value X cost of countermeasure
 Just in spec = just out of spec
 Trivial deviation from target will “stack up”
 Reduction in field failures will reduce factory failures

© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Taguchi vs. Zero Defects
• Consistent
• Predictable
• But not on target
• On target
• More variability
Who’s the better shot?
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Garvin’s Dimensions of Quality
Performance
 Features
 Reliability
 Conformance

Durability
 Serviceability
 Aesthetics
 Perception

“Managing Quality: The Strategic and
Competitive Edge,” David Garvin,
1988.
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Quality Dimensions

Tangible Goods
–
–
–
–
–
–
–
Safety
Durability
Reliability
Aesthetics
Conformance
Performance
Serviceability
© Fred Van Bennekom, Great Brook, 2003

Services
–
–
–
–
–
Reliability
Responsiveness
Assurance
Empathy
Tangibility
Slide ‹#›
Malcolm Baldrige National
Quality Award
Created by Public Law 1987
 Named after a Secretary of Commerce
 Three Purposes

– 1. To encourage quality in American industry
– 2. To promote quality awareness and continuous
improvement
– 3. To recognize companies that demonstrate
successful quality strategies and quality
achievement
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Lean Production

A combination of multiple tool sets
–
–
–
–
–
–
JIT production (cellular manufacturing)
Safe workplace (5Ss)
Pursuit of perfection
Visual management
Empowered teams
Six sigma
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Six Sigma vs. Lean – Complementary
Six Sigma
 Remove variation from
processes to achieve
uniform flow
 Problem/project focus
 Research projects with
longer timeline
(3-4 months)
 Higher complexity with root
cause unknown
© Fred Van Bennekom, Great Brook, 2003
Lean
 Remove waste, rework,
inventory to reduce flow
time
 Flow focused
– Remove bottlenecks
– Material velocity


Immediate results
(1-2 weeks)
Low complexity with
known solutions
Slide ‹#›
Lean Production
JIT production (cellular manufacturing)
 Heijunka: Level workloading
 Pursuit of perfection
 Visual process management
 Empowered teams
 Kaizen: Continuous improvement involving everyone
 Poka Yoke: mechanism to stop defects or make errors
obvious

© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Lean Concepts

Kaizen: Continuing improvement involving everyone
Poka Yoke: mechanism to stop defects or make errors obvious
Heijunka: Level production loading across all product
variations
Kanban: “Signboard” signal to authorize production
Andon: “Lantern” – board that signals quality issue
Jidoka: autonomation
5 Ss

Sources: www.superfactory.com, www.tpmonline.com






© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Other Kaizen Tools: 5 Ss
Step
1
2
3
4
5
Name
Sort
(Seiri)
Straighten, Set in Order
(Seiton)
Sweep, Shine
(Seiso)
Standardize
(Seiketsu)
Self-discipline, Sustain
(Shitsuke)
Action
Catch Phrase
Remove unnecessary items
from the workplace
“When in doubt, throw it out”
Locate everything at the point
of use
“A place for everything, and
everything in its place”
Clean and eliminate the
sources of filth
“The best cleaning is to not
need cleaning”
Make routine and standard for
what good looks like
“See and recognize what
needs to be done”
Sustain by making 5S second
nature
“The less self-discipline you
need, the better”
Source: http://www.kaizen-consulting.com/training_5s.htm
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›
Mudas – 7 Wastes
The 7 Wastes –
Definition
Over-|production
Producing more than the
customer needs right
now
Producing product to stock based on
sales forecasts
Producing more to avoid set-ups
Batch process resulting in extra output
Forecasting
Long set-ups
“Just in case” for breakdowns
Pull system scheduling
Heijunka – level loading
Set-up reduction
TPM
Transportation
Movement of product
that does not add value
Moving parts in and out of storage
Moving material from one workstation to
another
Batch production
Push production
Storage
Functional layout
Flow lines
Pull system
Value Stream organizations
Kanban
Motion
Movement of people that
does not add value
Searching for parts, tools, prints, etc.
Sorting through materials
Reaching for tools
Lifting boxes of parts
Workplace disorganization
Missing items
Poor workstation design
Unsafe work area
5S, Point of Use Storage
Water Spider
One-piece flow
Workstation design
Waiting
Idle time created when
material, information,
people, or equipment is
not ready
Waiting for parts
Waiting for prints
Waiting for inspection
Waiting for machines
Waiting for information
Waiting for machine repair
Push production
Work imbalance
Centralized inspection
Order entry delays
Lack of priority
Lack of communication
Downstream pull
Takt time production
In-process gauging
Jidoka
Office Kaizen
TPM
Processing
Effort that adds no value
from the customer’s
viewpoint
Multiple cleaning of parts
Paperwork
Over-tight tolerances
Awkward tool or part design
Delay between processing
Push system
Customer voice not understood
Designs “thrown over the wall”
Flow lines
One-piece pull
Office Kaizen
Lean Design
Inventory
More materials, parts, or
products on hand than
the customer needs right
now
Raw materials
Work in process
Finished goods
Consumable supplies
Purchased components
Supplier lead-times
Lack of flow, Long set-ups
Long lead-times
Paperwork in process
Lack of ordering procedure
External kanban
Supplier development
One-piece flow lines
Set-up reduction
Internal kanban
Defects
Work that contains
errors, rework, mistakes
or lacks something
necessary
Scrap, Rework
Defects
Correction
Field failure
Variation
Missing parts
Process failure
Mis-loaded part
Batch process
Inspect-in quality
Incapable machines
GembaSigma
Pokayoke
One-piece pull
Built-in quality
3P
Jidoka
Source:
www.Gemba.Com
Examples
© Fred Van Bennekom, Great Brook, 2003
Causes
Countermeasures
Slide ‹#›
Bibliography





The Six Sigma Way (ISBN 0-07-135806-4)
by Pande, Neuman, and Cavanaugh
The Power of Six Sigma (ISBN 0-79314434-5) by Subir Chowdhury
Six Sigma (ISBN 0-385-49437-8) by Harry
and Schroeder.
The Six Sigma Handbook (ISBN 0-07137233-4) by Pyzdek is more technical
and becoming the 'handbook' for Black
Belts.
The Machine that Changed the World,
James Womack
© Fred Van Bennekom, Great Brook, 2003




www.6-sigma.com
www.sixsigma.co.uk
www.sixsigmasystems.com
www.isixsigma.com

www.shawresources.com/pdf/Choosing%2
0a%20Quality%20Improvement%20Meth
odology.pdf

www.ge.com/en/commitment/quality/
whatis.htm

http://www.swmas.co.uk/Lean_Tools/The_
7_Wastes.php

http://www.kaizenconsulting.com/training_7w.htm
Slide ‹#›
More References

http://www.strategosinc.com/just_in_time.htm
– A GREAT summary of manufacturing improvement concepts from Ford
to lean. A MUST READ.



http://hbswk.hbs.edu/item.jhtml?id=2646&t=operations
http://www.kaizen-consulting.com/training_5s.htm
http://www.kaizen-consulting.com/training_7w.htm
– This site from Gemba Research does a nice job of summarizing lots of the
TPS tools and concepts.
© Fred Van Bennekom, Great Brook, 2003
Slide ‹#›