MGT 311 – intro to operation management

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6.2 Action Required:6.3 Test your Knowledge (Question):Q. What are the principles of Quality Management?————————————————————–7.2 Action Required: 7.3 Test your Knowledge (Question):Q. What do you understand by Supply chain Management?

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Chapter 9:
Quality Control and Improvement
McGraw-Hill Education
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9-1
Chapter 9 Learning Objectives
▪LO 9.1 Describe the steps in designing a quality control system.
▪LO 9.2 Design a process control system using control charts.
▪LO 9.3 Define and calculate process capability.
▪LO 9.4 Apply continuous improvement concepts using the seven quality tools.
▪LO 9.5 Explain Six Sigma and the DMAIC process.
▪LO 9.6 Differentiate lean and Six Sigma.
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9-2
Design of Quality Control Systems
▪Break down production process into subprocesses and identify internal customers.
▪Identify critical control points where
inspection or measurement should take
place.
▪Use operator inspection when possible,
placing responsibility for quality on workers.
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9-3
Design of Quality Control Systems

Identify critical points for inspection and testing
•
•
•

Incoming materials and services
During processes
Finished product or service
Decide on the type of measurement
•
•
Variables: continuous scale
Attributes: discrete count, or good/bad

Decide on amount of inspection to use

Decide who should do inspection
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9-4
Types of Measurement
Variables measurement
Product/service characteristic that can be measured on a continuous scale:
Length, size, weight, height, time, velocity, temperature
Examples: dimensions of parts, viscosity of liquids, weight of packaged food,
time to load webpage, temperature of coffee when served
Attributes measurement
Product/service characteristic evaluated with a discrete choice:
Good/bad, pass/fail, count of defects
Examples: laptop is defective if it fails any functional tests, bank check is/is not
deposited in correct account, inspection of fabric reveals the number
of defects per 100 yards
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9-5
Process Quality Control
Principles of Process Control:
◦ Every process has random variation.
◦ Production processes are not usually in a state of control.
“State of Statistical Control” – What does it mean?
◦ Unnecessary variation has been eliminated.
◦ Remaining variation is due to random causes.
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9-6
Process Quality Control
Assignable (special) cause variation
◦ Can be identified and corrected.
◦ Could be due to machine, worker, materials, etc.
Common (random) cause variation
◦ Reasonable, acceptable variation.
◦ Within 3 standard deviations ( 3) of mean.
◦ Cannot be changed unless process is redesigned.
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9-7
Quality Control Chart
y
Average + 3
standard
deviations
Upper control limit (UCL)
Quality
measurement
average
Center line (CL)
Average – 3
standard
deviations
Lower control limit (LCL)
Time →
x
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9-8
Normal Distribution on Control Chart
UCL
Mean
LCL
Assignable
causes likely
Samples:
1
2
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3
9-9
Attribute Control (3)
p-chart
Calculate center line = mean proportion defective
across many samples
Calculate upper and lower control limits
p (1 − p)
p3
n
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9-10
9-10
Variables Control (3)
x-chart
Calculate center line = mean of sample means
Calculate upper and lower control limits
x  A2 R
R-chart
Calculate center line = mean of sample ranges
Calculate upper and lower control limits
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UCL = D4 R
LCL = D 3 R
9-11
9-11
Quality Control Chart Example (Figure 9.2)
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12
Using Quality Control Charts
❑ If an observation (data point) is outside  3
and/or a pattern is detected, the process is
NOT in control.
❑ Very likely something is wrong.
❑ An assignable cause of variation may exist.
❑ This is a signal to take action to eliminate the
assignable cause:
◦ Find it, understand its cause, fix it so it does not occur again!
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9-13
Using Quality Control Charts
How large should sample be?
◦ Large enough to detect defects
◦ Variables can use smaller sample sizes
How frequently to sample?
◦ Depends on cost, production rate
Process control vs. Process capability
◦ Is the process capable of producing to specification?
◦ Are the specifications appropriate?
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9-14
Frequency
Process Capability Index (Figure 9.3)
Process measure
Process measure
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9-15
Frequency
Computation of Cpk (Figure 9.4)
Process measure
Process measure
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9-16
Continuous Improvement
➢ When process is not meeting customer
specifications.
➢ Work on processes with strategic importance and
low process capability first!
➢ Use the seven tools of quality control.
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9-17
Seven Tools of Quality Control
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9-18
Seven Tools of Quality Control
A battery manufacturer in NW Ohio,
using only the seven tools of quality,
decreased defectives from 7.2 per 100
to 2.6 per 100 in just 6 weeks!
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9-19
Pareto Analysis (Table 9.4)
Defect Items
Loose connections
Cracked connectors
Fitting burrs
Improper torque
O-rings missing
Total
# of Precent Cumulative
Defectives Defective Percentage
193
46.8%
46.8%
131
31.8%
78.6%
47
11.4%
90.0%
25
6.1%
96.1%
16
3.9%
100.0%
412 100.0%
Note: 40% (2) of the sources cause 78.6% of the defects.
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9-20
Pareto Diagram (Figure 9.6)
250
120.0%
# of Defectives
80.0%
150
60.0%
100
40.0%
50
Percentage
100.0%
200
20.0%
0
0.0%
Loose
connections
Cracked
connectors
Fitting burrs
Improper torque O-rings missing
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9-21
Cause-and-Effect (fishbone, Ishikawa) Diagram
(Figure 9.7)
Material
connectors
Workers
Small
Size
Large
Content
Nuts
Training
Size
Fatigue
Knowledge
Hose
Loose
connections
Surface defect
Measurement
Measuring
tools
Experience
Errors
Judgment
Inspector
Wear
Adjustment
Training
Inspection
Torque
Air pressure
Tools
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9-22
Six Sigma Quality
▪ Philosophy of 3.4 defects per million.
▪ Uses project/team approach.
▪ Strategic process is selected for improvement.
▪ Cross-functional team is formed.
▪ ‘Black belt’ leader is chosen.
▪ Team uses DMAIC method (and quality tools) to find root
causes and improve processes.
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9-23
Six Sigma Process
Process Improvement steps (DMAIC):
1. Define
2. Measure
3. Analyze
4. Improve
5. Control
– select process
– measure relevant variables
– determine root causes and alternatives
– change process
– ensure improvements not lost over time
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9-24
Lean and Six Sigma
Complementary approaches to improvement
◦
◦
Lean seeks to eliminate waste (non-value-added)
Six Sigma seeks to eliminate defects
◦
◦
Lean uses part-time leaders and all employees
Six Sigma uses full-time leaders and selected employees
◦
◦
Lean requires limited training
Six Sigma requires extensive training and experts
◦
◦
Lean focuses on simpler projects
Six Sigma takes on complex projects
◦
◦
Lean projects may last a week or less
Six Sigma projects may last for months
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9-25
Chapter 9 Summary
▪LO 9.1 Describe the steps in designing a quality control system.
▪LO 9.2 Design a process control system using control charts.
▪LO 9.3 Define and calculate process capability.
▪LO 9.4 Apply continuous improvement concepts using the seven quality tools.
▪LO 9.5 Explain Six Sigma and the DMAIC process.
▪LO 9.6 Differentiate lean and Six Sigma.
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9-26
Questions for Discussion
•In your own words, what is quality control?
•Why is quality control needed in manufacturing? In services?
•How do you decide which type of control chart may be useful for a
particularly situation?
•Look at the seven quality tools. Brainstorm various situations in which
each of the tools could be useful.
•Why is Six Sigma called “Six Sigma”?
•How are lean and Six Sigma the same, and how are they different?
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27
Chapter 8:
Managing Quality
McGraw-Hill Education
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8-1
Chapter 8 Learning Objectives
▪LO 8.1 Explain quality, from a customer perspective.
▪LO 8.2 Characterize product quality based on four dimensions.
▪LO 8.3 Distinguish service quality from product quality based on its distinct
measurement.
▪LO 8.4 Apply the quality cycle to a product or service.
▪LO 8.5 Explain how mistake-proofing and the supply chain are integrated with
quality management planning.
▪LO 8.6 Attribute how cost of quality is related to financial performance.
▪LO 8.7 Recall the two key quality pioneers and their main ideas.
▪LO 8.8 Compare and contrast ISO 9000 standards and the Baldrige Award criteria.
▪LO 8.9 Articulate some key barriers to successful quality improvement efforts.
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8-2
What is Quality Management?
Quality is one of the four key objectives of operations:
◦ cost, quality, delivery, flexibility
Historical development of quality concepts
◦ Inspection (early 1900s)
◦ Statistics quality control (Shewhart – 1940s)
◦ Quality management (1960s)
Quality
is now viewed
as the responsibility
of all functions
in the organization.
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8-3
Comair Flight 5191, Lexington, KY
“The Comair Flight 5191 crew began the day by powering
up the wrong plane. They took off down the wrong
runway. The air traffic controller, working alone in
violation of FAA policy, had turned his back to do other
duties. Investigators are uncovering a series of mistakes
before the plane crashed, killing 49 people.”
Source: www.cnn.com, 2006
Quality involves the entire organization and the supply chain.
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8-4
Definition of Quality
Meeting, or exceeding, customer
requirements now and in the future.
Meaning:
The product or service is fit for customer use.
Meaning:
Only the customer can determine quality.
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8-5
Dimensions of Product Quality
Availability
Quality of
Conformance
QUALITY
Field
Service
Quality of
Design
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8-6
Quality of Design
❖Determined before the product is produced
❖Responsibility of cross-functional product design team
❖Translates customer “wishes” into specifications
❖Depends on market research, design concept, product
specifications
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8-7
Quality of Conformance
✓ Producing a product (or service) that meets specifications
✓ Even ‘cheap’ products can have high conformance quality
– May not be durable, but conformance quality is achieved if
product matches the design.
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8-8
The “Abilities”
• Availability
• Continuity of usefulness to customers (operational)
• Reliability
• Useful product/service time until failure
• Mean time before failure (MTBF)
• Maintainability
• Restoration of product/service after failure
• Mean time to repair (MTTR)
Availability =
Uptime
Uptime + Downtime
MTBF
Availability =
MTBF + MTTR
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8-9
8-9
Availability Example
• A piece of medical testing equipment is typically used for
3 hours and then requires 1 hour of maintenance.
→ Calculate the machine’s availability.
Availability =
•
•
•
•
Uptime
Uptime + Downtime
Availability =
MTBF
MTBF + MTTR
MTBF = 3 hours
MTTR = 1 hour
Availability = 3 / (3 + 1) = .75
The machine’s average availability is 75%.
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8-10
8-10
Field Service
❑ Warranty and repair/replacement of the product after
it has been sold
❑ Also called customer service, sales service, or just
“service”
❑ Dimensions
◦ Promptness
◦ Competence
◦ Integrity
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8-11
Different Types of Quality (Figure 8.1)
Quality of market research
Quality of design
Quality of concept
Quality of specification
Technology
Customer
satisfaction
Quality of conformance
Employees
Management
Reliability
Fitness
for use
Availability
Maintainability
Logistical support
Promptness
Field service
Competence
Integrity
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8-12
Service Quality
• Includes explicit and implicit service characteristics
• Measures are perceptual/subjective
SERVQUAL is most popular measure
•
•
•
•
•
Tangibles → appearance
Dependability → promised service
Responsiveness → prompt, helpful
Assurance → knowledge, courtesy
Empathy → caring, individualized
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8-13
The Quality Cycle (Figure 8.2)
Needs
Crossfunctional
team
CUSTOMER
Product
Quality needs
MARKETING
Interprets customer needs
Works with customer to
design product
OPERATIONS
Produces the product
or services
Interpretation
of needs
ENGINEERING
Defines design concept
Prepares specifications
Defines quality characteristics
Specifications
QUALITY CONTROL
Plans and monitors
quality
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8-14
Quality Cycle in Mass Transit System (Figure 8.3)
County planning
Regional planning
State transportation agency
Riders’
needs
Operations office
Planner
Scheduler
Routes
Schedules
Budgets
Method
Facilities
Equipment
Evaluation
Inspection
Audits
Surveys
Hearings
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Public
8-15
Quality Improvement Cycle
 Define quality attributes on the basis of customer needs.
 Decide how to measure each attribute.
 Set quality standards.
 Establish appropriate tests for each standard.
 Find and correct causes of poor quality.
 Continue to make improvements.
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8-16
Poka-Yoke
(poh-kah yoh-kay)
Developed at Toyota, means ‘mistake proofing’
Design the product or process so that mistakes cannot
occur or are immediately detectable
Examples
– In manufacturing, 2 parts are notched to
only fit together one way
– For consumers, snow blower requires
that two hand levers be held during
operation (so no hands can be in the
dangerous moving parts!)
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8-17
Suppliers Role in Quality
Involve in product design
◦ Prevent design defects; help select materials
Supplier certification
◦ Planning and control system for quality
Manage rolled yield (cumulative defect rate)
◦ 10 parts (1% defects in each)
◦ Rolled yield = (.99)10 = .90
◦ 90% quality yield for final product
Boeing supplier rating system:
Red (Unsatisfactory)
Yellow (Improvement needed)
Bronze (Satisfactory)
Silver (Very Good)
Gold (Exceptional)
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8-18
Cost of Quality
Control ◦ Prevention
◦ Training, data management, planning
costs ◦ Appraisal
◦ Incoming materials inspection, final inspection
◦ Internal failure
Failure
◦ Scrap, rework, downtime
costs ◦ External failure
◦ Warranty, returns, complaints
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8-19
Cost of Quality Trade-offs (Figure 8.5)
Cost/unit
Internal &
external
failure costs
Prevention
& appraisal
costs
100%
defective
100%
good
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8-20
Quality Pioneer:
W. Edwards Deming
14 Management Principles
Do not sacrifice quality for short-term profit
Emphasis on continuous improvement
PDCA Wheel
◦ Plan, Do, Check, Act
http://www.deming.org/
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8-21
Quality Pioneer:
Joseph Juran
Quality “Trilogy”—planning, control and improvement
Solve “the vital few” quality problems
Stressed quality control methods
©Roger Schroeder
“Quality Handbook”

Home

Juran lived to age 104,
shown here with author
Roger Schroeder
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8-22
ISO 9000 Standards
▪ Guidelines for designing, manufacturing, selling, and
servicing products.
▪ Selecting ISO 9000 certified suppliers provides some
assurance that they follow accepted quality
practices.
▪ Many manufacturers require supplier certification,
particularly in Europe.
▪ www.iso.org
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8-23
ISO 14000 Standards
Standards covering environmental management systems,
environmental auditing, evaluation of environmental
performance, environmental labeling, and life-cycle
assessment.
Helps organizations improve their environmental
performance through documentation control, operational
control, control of records, training, statistical techniques,
and corrective and preventive actions.
ISO 26000 – social responsibility
ISO 31000 – risk management
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8-24
Baldrige Award
▪ Highest U.S. quality award.
▪ Promotes quality management practices and
improved quality results by U.S. industry.
▪ Award criteria are the standard for “best
quality practices” in U.S.
▪ Many state and other country awards
modeled on award criteria.
▪www.baldrige.gov
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Source: United States Department of Commerce
8-25
Baldrige Criteria Categories
1. Leadership
2. Strategy
3. Customers
4. Measurement, Analysis, and
Knowledge Management
5. Workforce
6. Operations
7. Results
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8-26
Why Some
Quality Improvement Efforts Fail
➢ Lack of middle and top management leadership attention
➢ Lack of funds for training and time for improvement activities
➢ “Blame the employee” rather than the system
➢ Belief in “trade-offs” (quality vs. cost)
➢ Management interference with teamwork
➢ Supplier quality problems
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8-27
Chapter 8 Summary
▪LO 8.1 Explain quality, from a customer perspective.
▪LO 8.2 Characterize product quality based on four dimensions.
▪LO 8.3 Distinguish service quality from product quality based on its distinct
measurement.
▪LO 8.4 Apply the quality cycle to a product or service.
▪LO 8.5 Explain how mistake-proofing and the supply chain are integrated with
quality management planning.
▪LO 8.6 Attribute how cost of quality is related to financial performance.
▪LO 8.7 Recall the two key quality pioneers and their main ideas.
▪LO 8.8 Compare and contrast ISO 9000 standards and the Baldrige Award criteria.
▪LO 8.9 Articulate some key barriers to successful quality improvement efforts.
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8-28
Questions for Discussion
•Look at a product you are carrying with you today. What design
characteristics contribute to its overall quality?
•Why does the customer need to define quality for a product or service?
•Consider your favorite restaurant or coffee shop. What “tangible”
observations contribute to your assessment of quality?
•Availability of a system is never 100%! What do you think the availability
of wifi on your campus is? Availability of your phone service?
•Can you think of examples of poka yokes? Have you designed some of
your own?
•Why don’t companies spend more on prevention of quality problems?
•Look up some Baldrige Award winning organizations. Are you a
customer of some of these?
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29
Chapter 7:
Lean Thinking and Lean Systems
McGraw-Hill Education
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1
Chapter 7 Learning Objectives
▪LO 7.1 Describe the origins and evolution of lean thinking.
▪LO 7.2 Describe the five tenets of lean thinking and the seven forms of waste
in a lean system.
▪LO 7.3 Explain why a stabilized master schedule is required for smooth flow.
▪LO 7.4 Explain how setup time, lot size, layout, and maintenance are related
to lean thinking.
▪LO 7.5 Differentiate how employees are unique in lean systems.
▪LO 7.6 Design a Kanban system to achieve customer pull.
▪LO 7.7 Compare lean suppliers to traditional manufacturing suppliers.
▪LO 7.8 Explain how to implement a lean system.
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7-2
Evolution of Lean
Toyota Production System (TPS)
◦ Developed in Japan following WWII (due to limited resources)
◦ Also known as Just-in-Time (JIT) manufacturing
◦ Came to U.S. in 1981 at Kawasaki motorcycle plant in Lincoln, Nebraska
1990s book,
“The Machine That Changed the World”
by Womack, Jones & Roos
Popularized a new label:
Lean Production
Walter Cicchetti/123RF
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7-3
Lean Tenets
Create product/service value from customer perspective
◦ Reduce waste – muda
Identify, study, improve the value stream
◦ Observe the process – gemba
Ensure simple, smooth, error-free flow
◦ Determine takt time
Produce only what is pulled by customer
◦ Use kanbans
Strive for perfection
◦ Hold kaizen events, 5S, 5 Whys
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7-4
Create Value: Seven Forms of Waste
Overproduction: Producing more than the demand for customers, resulting in
unnecessary inventory, handling, paperwork, and warehouse space.
Waiting time: Operators and machines waiting for parts or work to arrive from
suppliers or other operations. Customers waiting in line.
Unnecessary transportation: Double or triple movement of materials due to
poor layouts, lack of coordination, and poor workplace organization.
Excess processing: Poor design or inadequate maintenance or processes,
requiring additional labor or machine time.
Too much inventory: Excess inventory due to large lot sizes, obsolete items,
poor forecasts, or improper production planning.
Unnecessary motion: Wasted movements of people or extra walking to get
materials.
Defects: Use of material, labor, and capacity for production of defects, sorting
out bad parts, or warranty costs with customers.
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7-5
Value Stream Mapping
▪ Value stream is all processing steps to complete
product/service
▪ Extension of process flowcharting
▪ Includes value-adding/non-value-adding activities
▪ Requires direct observation of process – gemba
▪ “Is this step or task necessary in creating value for
the customer?”
▪ Change and improve process
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7-6
Example: Value Stream Mapping
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7-7
Water Level
Ensure Flow:
Inventory Hides Problems (Figure 7.2)
Bad
design
Poor
quality
Lengthy
setups
Inefficient
layout
Machine
breakdown
Unreliable
supplier
Water level indicates level of inventory in the system
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7-8
Lower Inventory Level Exposes Problems
Water Level
Bad
design
Poor
quality
Lengthy
setups
Inefficient
layout
Machine
breakdown
Unreliable
supplier
Water level indicates level of inventory in the system
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7-9
Water Level
Water Flows Smoothly…
Once Problems Resolved
Problems addressed/solved
Water level indicates level of inventory in the system
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7-10
Customer Pull:
Push versus Pull System (Figure 7.3)
▪ Downstream customer
signals need for good
or service.
▪ Signal is sent upstream
that production is
needed.
▪ No upstream process is
authorized to produce
until customer pulls,
thus minimizing
inventory in the system.
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Strive for Perfection:
Quality in a Lean System
Quality is essential input
into lean system.
Defects are waste.
No inventory to cover
up mistakes.
System designed to
expose errors; correct
them at their source (so
not repeated in the future).
Continuous improvement
of the process.
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7-12
5 Whys Technique
Explores cause-and-effect relationships that underlie problems
(root causes)
Enables root causes to be identified/resolved
Example: Truck won’t start.
◦
◦
◦
◦
◦
◦
Why? Battery is dead.
Why? Alternator is not functioning.
Why? Alternator belt is broken.
Why? Truck was not maintained as recommended.
Why? Truck is old; no replacement parts available.
Solution? Find source for parts, or purchase new truck.
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7-13
5S Technique
Organize workspace to improve employee morale, safety, efficiency.
Reduces time looking for “things.”
• Seiri
to Sort (keep, toss)
• Seiton
to Straighten or set in order
• Seiso
to Shine, sweep, or clean
• Seiketsu to Standardize
• Shitsuke to Sustain (maintain)
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Example: 5S Technique
Storage of chemicals in production area
Before
• Quantities greater than needed
• Difficult to see what is missing
• Hard to find anything
After Source: The Lean & Chemicals Toolkit/U.S. Environmental Protection Agency
• Appropriately sized quantities
• Quickly see what is missing
• Easy to find anything
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7-15
Creating Flow
✓ Stabilize master schedule
✓ Reduce setup times and lot sizes
✓ Change to cellular layout and preventative maintenance
✓ Cross-train and engage workers
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Stabilize the Master Schedule
❖ Production horizon set according to demand.
❖ Production schedule repeated each day.
❖ Uniform load: level work load across workers/machines.
❖ Takt time: match supply (production rate) to demand rate .
❖ Produce planned quantity each day, and no more.
❖ These concepts are desirable, but not essential, to a lean system.
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7-17
Reduce Setup Time and Lot Size
Reducing setup time…
◦ increases available capacity
◦ increases flexibility to meet schedule changes
◦ reduces inventory
Setup types
◦ Single (single digit minutes)
◦ One-touch (less then 1 min; 2-step process)
◦ Internal (while machine stopped)
◦ External (while machine operating)
Lot size reduction
◦ Goal: single unit production
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7-18
Cellular Layout (Figure 7.4)
• Inventory kept on
shop floor close to
where it is used.
• Eliminates wasted
transportation
moving materials.
• Work centers
organized into
group technology
layout – cellular
manufacturing.
• U-shape ensures
flow without
interruption.
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7-19
Engaging Workers
Multifunction, cross-trained workers
◦ Flexibility to move to busy work centers
New pay system to reflect skills variety
Workers contribute individually and collaboratively
◦ Perform own maintenance and inspection
◦ Teamwork, problem solving
◦ Suggestion systems
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7-20
Pull:
Kanban System
❖Signals the need for more parts
❖Uses simple cards or signals to control production and inventory
❖Each work center receives production order (signal or card)
from succeeding (downstream) work center
❖Prevents buildup of inventory
❖Reduces lead time
❖Same concept applies to receiving deliveries from suppliers
(supplier must wait for signal)
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Kanban System (Figure 7.5)
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Kanban System
Kanban: “marker” (card, sign, empty container)
Visual control system of cards and containers, or other signal.
Number of containers:
DT
n=
C
D = Demand rate (at work center)
T = Time for container to complete circuit
C = Container size (# units)
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7-23
Kanban Containers – Example
▪ Demand at work center B is 5 parts per minute and a
standard container holds 50 parts.
▪ It takes 90 minutes for a container to make a complete circuit
through work center A and work center B (and back to A),
including all setup, run, move, and wait times.
The number of containers needed:
n = 5(90) / 50 = 9 containers
The maximum inventory in the production system, a useful
measure of how lean the system is:
Maximum inventory = nC = DT = (9 × 50) = (5 × 90)
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24
Supplier Relationships
▪ Viewed as the ‘external factory’
▪ Co-location, frequent deliveries
▪ Fewer suppliers
▪ No inspection—high quality is assumed (required)
▪ Integrated supplier programs
▪ Early supplier selection
▪ Family-of-parts sourcing
▪ Long-term strategic relationship
▪ Reduce paperwork and inspection
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Implementation: Kaizen Event
✓Establish a cross-functional team
✓Determine what customers value
✓Construct value stream map
Eliminate waste (non-value-adding activities)
✓Create smooth and error-free flow
✓Use customer demand to pull work thru process
✓Implement team ideas
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7-26
Chapter 7 Summary
▪LO 7.1 Describe the origins and evolution of lean thinking.
▪LO 7.2 Describe the five tenets of lean thinking and the seven forms of waste
in a lean system.
▪LO 7.3 Explain why a stabilized master schedule is required for smooth flow.
▪LO 7.4 Explain how setup time, lot size, layout, and maintenance are related
to lean thinking.
▪LO 7.5 Differentiate how employees are unique in lean systems.
▪LO 7.6 Design a Kanban system to achieve customer pull.
▪LO 7.7 Compare lean suppliers to traditional manufacturing suppliers.
▪LO 7.8 Explain how to implement a lean system.
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7-27
Questions for Discussion
•Why did lean (Toyota Production System) work so well in Japan after
World War II?
•Choose one of the Japanese words from the 5 lean tenets and explain
it in your own words.
•Which of the 7 forms of waste can you observe at your favorite
restaurants?
•What does it mean to say that “inventory hides problems” in a
production system?
•Consider what “setup time” looks like in different industries:
hospitals, quick oil change shops, restaurants, garment producing
factories.
•Make a mental list of how you would “5S” your own refrigerator.
Then, share your ideas with classmates and compare how they
approached this task.
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