Operations Management:
Lean Operations (JIT) Module

MBPF House Manufacturing Game
» The transition to Lean Ops

The Paradigm of Lean Operations: The ideal
» Basic philosophy of Lean Ops
» Methods for synchronization & waste reduction

Approaching the ideal with Product Variety: TPS
» Managing variety & flexibiltiy
» Toyota Production System (TPS)
S. Chopra/Operations/Lean Ops
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MBPF Inc. Factory Layout
Production Control
Roof Punch
Base Punch
Roof Form
Base Form
Base Weld
Final Assembly
S. Chopra/Operations/Lean Ops
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Paradigm of Lean Operations:
In Search for the Holy Grail
= The ideal Process
 Synchronization of all flows
» 1x1
» production on demand
» defect free
 At
lowest possible cost
 Waste
= Gap between ideal and actual
How do we set up a system to continually reduce
waste ?
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Toyota’s waste elimination in
Operations
1. Overproduction
2. Waiting
3. Inessential handling
4. Non-value adding processing
5. Inventory in excess of immediate needs
6. Inessential motion
7. Correction necessitated by defects
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Synchronize:
Cut Batch Sizes
Example Process:
0
1
2
3
4
5
B
C
D
1 min/job
1 min/job
1 min/job
1 min/job

Batch Mfg (Lotsize = 5)
5
Space
5
A
10
Time
A
15
20
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B
C

0
1
2
3
4
5
D
Flow Mfg (Lotsize = 1)
Space
1
1
1
1
A
5
1
B
C
D
10
5
15
5
20
5
Synchronize: Heijunka
Mixed Level/Balanced Production
Batch Production Schedule
(AAAABBBB..)
Product
Mixed Production Schedule
(ABAB...)
Apr/12.................15...........................30
Apr/12....................15.......................30
A
B
FGI
FGI
time
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time
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Synchronize: Heijunka
Uniform Plant Loading

This does not mean building a single product.

Rather:
– maintain a stable mix of products,
– and firm frozen schedules
Costs:
S. Chopra/Operations/Lean Ops
Must reduce changeover costs
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Synchronization with demand:
customer demand pulls product
PUSH: Inputs availability triggers execution
Supplier
Process
inputs
Customer
outputs
PULL: Outputs need triggers execution
Supplier
Process
inputs
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Customer
outputs
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Implementation:
Kanban Production Control Systems
Kanban
Job
Processing
center i
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WIP
Processing
center i + 1
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Reducing Waste:
Quality at the Source
Defects
Found at:
Impact to the
Company
S. Chopra/Operations/Lean Ops
Own Process
Next Process
End of Line
Final
Inspection
End User’s
Hand
$
$
$
$
$
 Very
Minor
 Minor
Delay
 Rework
 Resched.
of work
 Significant
Rework
 Delay in
Delivery
 Additional
Inspection
 Warranty
costs
 Administra
tive costs
 Reputation
 Loss of
Market
Share
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Reducing Waste:
Flexible Resources
 Cross
training of workforce
 Use of IT in services
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Reducing Waste:
From Functional Layout to Cells
Production
Control
Production
Control
Roof
Cut
FA
QC
Roof
Cut
FA
QC
S. Chopra/Operations/Lean Ops
Production
Control
Roof
Cut
FA
QC
Base
Cut
Production
Control
Base
Cut
Base Base
Assy Assy
Base
Cut
Base
Assy
Roof
Cut
Base
Cut
FA
Base
Assy
Production
Control
Production
Control
Roof
Cut
Base
Cut
Roof
Cut
Base
Cut
FA
Base
Assy
FA
Base
Assy
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Synchronize:
Just-In-Time operations
JIT = have exactly what is needed, in the quantity it
is needed, when it is needed, where it is needed.
 Synchronize
process flows
 From The Goal “Balance flows”
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Reducing waste: Increase Problem Visibility
Lower the Water to Expose the Rocks
Inventory
Missed Due Dates
Late
Deliveries
Too much paperwork
Engineering
Change Orders
Scrap &
Rework
Poor
Quality
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Too Much
Space
100% inspection
Long queues
Machine
Downtime
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Time plays the role of Inventory in
Lean Service Operations
TIME
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Continuous Improvement: Kaizen
 Increase
visibility of waste
 Exploratory stress
 Targeted improvements
– Active worker involvement
– Time for experimentation
– Supplier involvement
 Human infrastructure
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Lean Operations:
Best Implementation is TPS
 TPS
is a production management system that aims
for the “ideal” through continuous improvement
 Includes, but goes way beyond JIT. Pillars:
– Synchronization: through small batch sizes, heijunka,
pulling of work,quality at source, and cellular
manufacturing
– Continuous Improvement (Kaizen): through visibility,
stress, and empowerment
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....
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Learning Objectives:
Lean Operations for Variety

Lean Operations: In Search for the Holy Grail and zero
Waste
– Level Mixed Production: Heijunka
» Reduced batch sizes
–
–
–
–
Pull Execution: Kanbans
Quality at source: Jidoka
Efficient Workflow: Cellular Layout
Continuous Improvement: Kaizen
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Flow Synchronization
Low cost
Get closer to ideal
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