*Lean Operations and the Toyota
Production System
C&T 10
*aka Just-in-Time or the Toyota Production System
Just In Time
More than just low inventory
JIT goals:
–
–
–
–
Exactly what is needed
Exactly how much is needed
Exactly when it is needed
Exactly where it is needed.
Achieved by:
– eliminating disruptions
– making the system flexible
– eliminating waste
Batch Sizing
$
0
Q
7 Wastes
1.
2.
3.
4.
5.
6.
7.
Defects
Too much product
Carrying inventory
Waiting
Unnecessary processing
Unnecessary worker movement
Transporting materials
The Four Rules
1. How people work
2. How people connect
3. How the production line is constructed
4. How to improve
Decoding the DNA of the Toyota Production System, Spear &
Bowen, Harvard Business Review, 9/10 1999 pp. 96-106.
Cellular Layouts
• Product vs. process layout
– Transportation
– Transfer batch
– Communication
– Feedback
5S
Seiri
整理
Sort
Seiton
整頓
Set in order
Seiso
清掃
Shine
Seiketsu
清潔
Standardize
Shitsuke
躾
Sustain
Visual Systems
• Kanbans
• Andons
• Footprinting & shadow boards
• Color coding
Worker Training
• Teams
• Cross-training
• Quality Circles
• Kaizen
• Process quality
Schonberger’s JIT diagram
Ideas for
cutting lot
sizes
Ideas for
improving JIT
performance
Lot Size
Reduction
JIT
production
Less
inventory in
the system
Reduced buffer
inventories
and/or workers
Heightened
awareness
of problems
and causes
Less
indirect
costs for
inventory
Ideas for
controlling defects
Fast feedback
on defects
Scrap/quality
Control
Higher
quality
finished
goods
Fewer
rework labor
hours
Smoother
Output Rates
Less
Material
Waste
Less material, labor & indirect = higher productivity
Less inventory = faster response, less admin & better forecasting