lean manufacturing .H.Badkook

lean manufacturing system
lean manufacturing system
Toyota Production systems
Toyota Production systems
( TPS )
( TPS )
Prepared by : Hassan Omar Badkook
2009
What is lean manufacturing?
What is lean manufacturing?
Definitions :
Definitions :
►
►
LM is a set of tools and methodologies that aims for the conti
LM is a set of tools and methodologies that aims for the conti
nuous
nuous
elimination of all waste in the production process.
elimination of all waste in the production process.
►
►
a system approach to identifying and eliminating waste (non
a system approach to identifying and eliminating waste (non
-
-
value added
value added
activities) through continuous improvement by flowing the p
activities) through continuous improvement by flowing the p
roduct at

roduct at
the pull of the customer in pursuit of perfection
the pull of the customer in pursuit of perfection
-
-
The main benefits of LM are lower production costs , increased
The main benefits of LM are lower production costs , increased
output and shorter
output and shorter
production lead times.
production lead times.
Key principles of lean manufacturing
Key principles of lean manufacturing
1
1
-
-
Recognition of waste:
Recognition of waste:
-
-
The first step is to recognize what does and does not create va
The first step is to recognize what does and does not create va
lue from the
lue from the
customer
customer
’
’
s perspective.

s perspective.
-
-
Any material , process or feature which is not required for cre
Any material , process or feature which is not required for cre
ating value from the
ating value from the
customer
customer
’
’
s perspective is waste and should be eliminated
s perspective is waste and should be eliminated
2
2
-
-
Standard processes :
Standard processes :
-
-
Lean requires an the implementation of very detailed production
Lean requires an the implementation of very detailed production
guidelines, called
guidelines, called
(standard work)
(standard work)
-
-
Clearly state the content , sequence , timing and outcome of a

Clearly state the content , sequence , timing and outcome of a
ll actions by workers.
ll actions by workers.
-
-
This eliminate variation in the way that workers perform their
This eliminate variation in the way that workers perform their
tasks
tasks
3
3
-
-
continuous flow :
continuous flow :
-
-
Lean aims to a continuous production flow free of bottlenecks,
Lean aims to a continuous production flow free of bottlenecks,
interruption
interruption
,backflows or waiting.
,backflows or waiting.
-
-
Production cycle time can be reduced by as much as 90%
Production cycle time can be reduced by as much as 90%
4
4
-

-
pull
pull
-
-
production( also called Just
production( also called Just
-
-
in
in
-
-
time)
time)
-
-
Aims to produce only what is needed , when it is needed.
Aims to produce only what is needed , when it is needed.
-
-
Production is pulled by the downstream workstation so that each
Production is pulled by the downstream workstation so that each
workstation should only
workstation should only
produce what is requested by the next workstation.
produce what is requested by the next workstation.
Key principles of lean manufacturing
Key principles of lean manufacturing
5

5
-
-
Quality at source:
Quality at source:
-
-
lean aims for
lean aims for
-
-
Defects to be eliminated at the source
Defects to be eliminated at the source
-
-
Quality inspection to be done by the workers as part of the in
Quality inspection to be done by the workers as part of the in
-
-
line production
line production
process.
process.
6
6
-
-
Continuous improvement:
Continuous improvement:
-

-
Lean requires striving for perfection by continually removing l
Lean requires striving for perfection by continually removing l
ayers of waste as they
ayers of waste as they
are unconverted.
are unconverted.
-
-
This in turn requires a high level of worker involvement in the
This in turn requires a high level of worker involvement in the
continuous
continuous
improvement process.
improvement process.
History of lean manufacturing
History of lean manufacturing
Key implications of lean manufacturing
Key implications of lean manufacturing
Lean manufacturing
Lean manufacturing
Traditional batch
Traditional batch
manufacturing
manufacturing
Customer driven
Customer driven
Supply driven
Supply driven
Orientation

Orientation
Orders are pulled through factory
Orders are pulled through factory
based on customer/downstream
based on customer/downstream
demand
demand
Orders are pushed through factory
Orders are pushed through factory
based on production plan/forecast
based on production plan/forecast
Planning
Planning
Small
Small
large
large
Batch size
Batch size
In
In
-
-
line inspection by workers
line inspection by workers
Checking of samples by QC
Checking of samples by QC
inspectors
inspectors
Quality inspection

Quality inspection
Little or no work
Little or no work
-
-
in
in
-
-
progress
progress
between each production stage
between each production stage
Buffer of work
Buffer of work
-
-
in
in
-
-
progress between
progress between
each production stage
each production stage
Inventory
Inventory
Materials handed off directly from
Materials handed off directly from
one production stage to the next

one production stage to the next
Materials after each stage accumulate
Materials after each stage accumulate
into works
into works
-
-
in
in
-
-
progress storage areas
progress storage areas
before being retrieved by next
before being retrieved by next
production stage
production stage
Handoff of works
Handoff of works
-
-
in
in
-
-
process
process
Total production cycle shortens to
Total production cycle shortens to
approach time spent actually

approach time spent actually
processing the materials
processing the materials
Total production cycle takes
Total production cycle takes
significantly longer than actual time
significantly longer than actual time
spent processing the materials
spent processing the materials
Production cycle time
Production cycle time
Lean manufacturing goals
Lean manufacturing goals
▪
▪
Eliminate disruption
Eliminate disruption
▪
▪
Make system flexible by reduce setup and
Make system flexible by reduce setup and
lead times
lead times
▪
▪
Eliminate waste
Eliminate waste
▪
▪
Sources of waste ( non

Sources of waste ( non
-
-
value adding )
value adding )
▪
▪
Originally 7 main types of waste
Originally 7 main types of waste
-
-
Over
Over
-
-
production
production
-
-
Waiting time
Waiting time
-
-
Unnecessary transportation
Unnecessary transportation
-
-
Processing waste
Processing waste
-

-
Inefficient work methods
Inefficient work methods
( Motion waste)
( Motion waste)
-
-
Product defects
Product defects
-
-
Excess inventory
Excess inventory
Main kinds of waste
Main kinds of waste
►
►
Originally 7 main types of waste were identified as part of the
Originally 7 main types of waste were identified as part of the
Toyota
Toyota
Production System.
Production System.
►
►
This list has been modified and expanded by various practitioner
This list has been modified and expanded by various practitioner
s of lean
s of lean
manufacturing and generally includes the following :

manufacturing and generally includes the following :
1
1
-
-
Over
Over
-
-
production waste:
production waste:
▪
▪
Unnecessarily producing more than demanded
Unnecessarily producing more than demanded
▪
▪
Producing it too early before it is needed
Producing it too early before it is needed
That will be:
That will be:
-
-
Increase the risk of obsolescence
Increase the risk of obsolescence
-
-
Increase the risk of producing the wrong thing
Increase the risk of producing the wrong thing
-

-
Increases the possibility of having to sell those items at a di
Increases the possibility of having to sell those items at a di
scount or discard them as
scount or discard them as
scrap.
scrap.
Main kinds of waste
Main kinds of waste
2
2
-
-
Waiting waste:
Waiting waste:
▪
▪
Waiting is idle time for workers or machines due to bottlenecks
Waiting is idle time for workers or machines due to bottlenecks
or inefficient
or inefficient
production flow on the factory floor.
production flow on the factory floor.
▪
▪
Waiting also includes small delays between processing of units.
Waiting also includes small delays between processing of units.
Waiting results in
Waiting results in
a significant cost insofar as it increases labor costs and

a significant cost insofar as it increases labor costs and
depreciation costs per unit of output.
depreciation costs per unit of output.
3
3
-
-
Transportation waste:
Transportation waste:
▪
▪
Transportation includes any movement of materials that does not
Transportation includes any movement of materials that does not
add any value to the
add any value to the
product, such as moving materials between workstations.
product, such as moving materials between workstations.
▪
▪
The idea is that transportation of materials between production
The idea is that transportation of materials between production
stages should aim for
stages should aim for
the ideal that the output of one process is immediately used
the ideal that the output of one process is immediately used
as the input for the
as the input for the
next process.
next process.
Transportation between processing stages results in

Transportation between processing stages results in
prolonging
prolonging
production cycle times , the inefficient use of labor and space
production cycle times , the inefficient use of labor and space
and can also be a
and can also be a
source minor production stoppages.
source minor production stoppages.
Main kinds of waste
Main kinds of waste
4
4
-
-
over
over
-
-
processing:
processing:
▪
▪
Over
Over
-
-
processing is unintentionally doing more processing work than th
processing is unintentionally doing more processing work than th
e customer

e customer
requires in terms of product quality or features
requires in terms of product quality or features
–
–
such as polishing or applying
such as polishing or applying
finishing on some areas of a product that won't be seen by the c
finishing on some areas of a product that won't be seen by the c
ustomer
ustomer
5
5
-
-
Motion waste:
Motion waste:
▪
▪
Motion includes any unnecessary physical motion or walking by w
Motion includes any unnecessary physical motion or walking by w
orkers which
orkers which
diverts them from actual processing work.
diverts them from actual processing work.
For example
For example
-
-
Include walking around the factory floor to look for a tool

Include walking around the factory floor to look for a tool
-
-
Difficult physical movements, due to poorly designed ergonomics
Difficult physical movements, due to poorly designed ergonomics
which slow
which slow
down the workers.
down the workers.
Main kinds of waste
Main kinds of waste
6
6
-
-
Defects waste
Defects waste
▪
▪
Physical defects which directly add to the costs of good sold.
Physical defects which directly add to the costs of good sold.
▪
▪
Errors in paperwork.
Errors in paperwork.
▪
▪
Provision of correct information about the product.
Provision of correct information about the product.
▪

▪
Late delivery.
Late delivery.
▪
▪
Production to incorrect specifications.
Production to incorrect specifications.
▪
▪
Use of too much raw materials or generation of unnecessary scra
Use of too much raw materials or generation of unnecessary scra
p.
p.
7
7
-
-
Inventory waste:
Inventory waste:
▪
▪
Having unnecessary high levels of raw materials, works
Having unnecessary high levels of raw materials, works
-
-
in
in
-
-
progress and finished

progress and finished
products.
products.
▪
▪
Extra inventory leads to higher inventory financing costs, high
Extra inventory leads to higher inventory financing costs, high
er storage costs and
er storage costs and
higher defect rates.
higher defect rates.
Main kinds of waste
Main kinds of waste
8
8
-
-
Correction waste:
Correction waste:
▪
▪
When something has to be re
When something has to be re
-
-
done because it wasn't done correctly the first time.
done because it wasn't done correctly the first time.
▪
▪
This not only results in inefficient use of labor and equipment

This not only results in inefficient use of labor and equipment
but
but
the act of
the act of
reprocessing often causes disruptions to the smooth flow of p
reprocessing often causes disruptions to the smooth flow of p
roduction and
roduction and
therefore generates bottlenecks and stoppages.
therefore generates bottlenecks and stoppages.
▪
▪
Also,
Also,
issues associated with reworking typically consume a significan
issues associated with reworking typically consume a significan
t amount of
t amount of
management time and therefore add to factory overhead costs.
management time and therefore add to factory overhead costs.
9
9
-
-
Knowledge disconnection:
Knowledge disconnection:
▪
▪
This is when information or knowledge isn't available where or

This is when information or knowledge isn't available where or
when it is needed.
when it is needed.
▪
▪
This might include information on correct procedures, specifica
This might include information on correct procedures, specifica
tions, ways to solve
tions, ways to solve
problems, etc
problems, etc
▪
▪
Lack of correct information often leads to
Lack of correct information often leads to
defects and bottlenecks.
defects and bottlenecks.
▪
▪
For example
For example
, unavailability of a mixing formula may potentially suspend the
, unavailability of a mixing formula may potentially suspend the
entire
entire
process or create defective items due to time
process or create defective items due to time
-
-
consuming trial

consuming trial
-
-
and
and
-
-
error tests
error tests
.
.
JIT/Lean production
JIT/Lean production
Just
Just
-
-
in
in
-
-
time
time
-
-
A highly coordinated production system in which processing a
A highly coordinated production system in which processing a
nd
nd
movement of materials and goods occur just as they are nee

movement of materials and goods occur just as they are nee
ded (perfect
ded (perfect
timing), usually in small batches.
timing), usually in small batches.
-
-
Developed in Toyota
Developed in Toyota
®
®
by Taiichi Ohno (Vice president of
by Taiichi Ohno (Vice president of
manufacturing) in the so
manufacturing) in the so
-
-
called Toyota Production System (TPS).
called Toyota Production System (TPS).
-
-
JIT is characteristic of lean production systems where JIT
JIT is characteristic of lean production systems where JIT
operates with
operates with
very little
very little
“
“
fat

fat
”
”
Example : JIT at Hewlett
Example : JIT at Hewlett
-
-
Packard
Packard
How much JIT reduced waste at Hewlett
How much JIT reduced waste at Hewlett
-
-
Packard
Packard
®
®
Waste Reduction (%)
82%
50%
50%
30%
30%
20%
40%
0% 20% 40% 60% 80% 100%
Work-in-Process Inventory
Raw Material Inventory
Lead Time
Space

Finished Goods Inventory
Scrap
Setup Time
JIT/lean streamlines production
JIT/lean streamlines production
Flow with JIT
Traditional Flow
Customers
Suppliers
Customers
Suppliers
Production Process
(stream of water)
Inventory (stagnant
ponds)
Material
(becomes like
water in
stream)
Lean manufacturing tools and methodology
Lean manufacturing tools and methodology
►
►
Standard work
Standard work
►
►
Communication of standard work to employees
Communication of standard work to employees
►

►
Standard work and flexibility
Standard work and flexibility
►
►
Visual Management
Visual Management
►
►
Quality and the source ( or
Quality and the source ( or
“
“
Do it right the first time
Do it right the first time
”
”
)
)
►
►
Value Stream Mapping
Value Stream Mapping
►
►
The Five S
The Five S
’
’
s

s
►
►
Preventive Maintenance
Preventive Maintenance
►
►
Total Productive Maintenance
Total Productive Maintenance
►
►
Changeover/setup time
Changeover/setup time
►
►
Batch size reduction
Batch size reduction
►
►
Production Layout and point of use storage
Production Layout and point of use storage
►
►
Kanban
Kanban
►
►
Production Leveling
Production Leveling
►

►
Pacemaker
Pacemaker
►
►
Overall Equipment Effectiveness
Overall Equipment Effectiveness
Lean/JIT Goals and Building Blocks
Lean/JIT Goals and Building Blocks
Lean/JIT Building Blocks
Lean/JIT Building Blocks
1
1
-
-
Product design
Product design
2
2
-
-
Process design
Process design
3
3
-
-
personnel/organization elements
personnel/organization elements
4

4
-
-
manufacturing planning and control
manufacturing planning and control
1
1
-
-
product design
product design
►
►
standard parts
standard parts
-
-
use of standard parts leads to :
use of standard parts leads to :
fewer parts
fewer parts
-
-
reduced training time and costs
reduced training time and costs
-
-
routine
routine
purchasing and handling

purchasing and handling
-
-
low quality costs
low quality costs
►
►
modular design
modular design
-
-
Clusters of parts treated as a single unit
Clusters of parts treated as a single unit
-
-
reduced
reduced
assembly and handling costs
assembly and handling costs
►
►
quality
quality
-
-
Quality built into the product and the processes
Quality built into the product and the processes
►
►
concurrent engineering

concurrent engineering
-
-
Design and manufacturing work together
Design and manufacturing work together
early in the design stage (integrating
early in the design stage (integrating
production functions)
production functions)
1.1 standardized parts
1.1 standardized parts
1.2 modular design
1.2 modular design
Design modular components that can be configured into a wide variety
of end products and services
Modular Drills
1.3 quality in design
1.3 quality in design
Quality function deployment (QFD) and House of quality
Voice of the customer)(
THE HOUSE OF QUALITY
Customer
Requirements
Importance to Cust.
Easy to close
Stays open on a hill
Easy to open
Doesn’t leak in rain
No road noise
Importance weighting

Engineering
Characteristics
Energy needed
to close door
Check force
on level
ground
Energy needed
to open door
Water resistance
10 6 6 9 2 3
7
5
3
3
2
X
X
X
X
X
Correlation:
Strong positive
Positive
Negative
Strong negative
X
*
Competitive evaluation
X = Us

A = Comp. A
B = Comp. B
(5 is best)
1 2 3 4 5
X
AB
X AB
XAB
A X B
X A
B
Relationships:
Strong = 9
Medium = 3
Small = 1
Target values
Reduce energy
level to
7.5
ft
/
lb
Reduce force
to
9
lb
.
Reduce energy
to
7.5

ft
/
lb
.
Maintain
current level
Technical evaluation
(5 is best)
5
4
3
2
1
B
A
X
BA
X
B
A
X
B
X
A
BXA
BA
X
Door seal
resistance
Accoust. Trans.

Window
Maintain
current level
Maintain
current level
House of Quality Example
House of Quality Example
1.4 concurrent engineering
1.4 concurrent engineering
2
2
-
-
Process design
Process design
►
►
small batch size
small batch size
►
►
setup time reduction
setup time reduction
►
►
manufacturing cells
manufacturing cells
►
►
limited work in process

limited work in process
►
►
quality improvement
quality improvement
►
►
production flexibility
production flexibility
►
►
little inventory storage
little inventory storage