Transcript Just-In-Time Systems

Just-In-Time Systems
Chapter 9
David Bakuli
Production & Operations Management
9-2
Outline
• Philosophy of JIT
• Elements of a JIT
system
• Stabilizing the
Master Schedule
• The Kanban System
• Reducing Setup Time
and Lot Sizes
Westfield State College
• Layout and
Equipment
• Effect on Workers
• Suppliers
• Implementation of
JIT
• Comparison of JIT
and MRP
• Beyond JIT to TimeBased Competition
Production & operations Management
9-3
Philosophy of JIT
• Roots of JIT (Toyota Production
System)
• Philosophical tenets of JIT
• Root of JIT in “repetitive”
manufacturing
Westfield State College
Production & operations Management
9-4
Elements of JIT
• Small lot sizes
• Use of Kanban system
• Quick changeover
• Multifunction workers
• Efficient layout
• Close relationship with supplier
• Frequent delivery of supplies
Westfield State College
Production & operations Management
9-5
Elements of JIT
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Westfield State College
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Production & operations Management
9-6
Kanban System
• A “pull” production system
• A physical control system
• Composed of cards and containers
(production card and withdrawal
card)
• Number of containers
Westfield State College
Production & operations Management
9-7
Kanban System
Westfield State College
Production & operations Management
9-8
Kanban Cards
Westfield State College
Production & operations Management
9-9
Reducing Setup Time and Lot
Sizes
• Reducing setup time:
– increases available capacity
– increases flexibility
– reduces inventory
• Reducing setup times and run
times simultaneously
• Single-digit Setup Times
Westfield State College
Production & operations Management
9 - 10
JIT Layout
Work Centers
Final
Assembly
Stockrooms
Supplier A
Supplier B
Initial Layout
Westfield State College
Production & operations Management
9 - 11
JIT Layout
Final
Assembly
Supplier A
Supplier B
JIT Layout
Westfield State College
Production & operations Management
9 - 12
JIT Layout
Final
Assembly
Line 1
Line 2
Supplier A
Supplier B
JIT Layout with GT
Westfield State College
Production & operations Management
9 - 13
Effect of JIT on Workers
• Multifunction workers
• Cross-training
• New pay system to reflect skills
variety
• Teamwork
• Suggestion system
Westfield State College
Production & operations Management
9 - 14
Suppliers
• Very close relationship with
suppliers
• Frequent deliveries demanded
from suppliers
• Sole-sourcing
• Integrated supplier program
Westfield State College
Production & operations Management
9 - 15
Features of Integrated Supplier
Programs
• Early supplier selection
• Family of part sourcing
• Long-term relationship
• Cost-analysis-based price
negotiations
• Paperwork reduction in receiving
and inspection
Westfield State College
Production & operations Management
9 - 16
Implementation of JIT
• Obtain commitment from top
management
• Gain the cooperation of workforce
• Start with final assembly line
• Reduce setup times and lot sizes
working backward from the final
assembly line
• Balance fabrication rates with final
assembly production rates
• Extend JIT to the suppliers
Westfield State College
Production & operations Management
9 - 17
Comparison of MRP and
JIT
• Pull versus Push production
systems
• Situations for comparing MRP and
JIT:
– Pure repetitive manufacturing
situation
– A batch process
– A job shop
Westfield State College
Production & operations Management
9 - 18
Uses of MRP and JIT
JIT
Repetitive (mass)
MRP
SYNCRO MRP Nonrepetitive
Semirepetitive (batch or job
shop)
JIT
SYNCRO MRP
MRP
High
Low
Stability of Master Schedule
Stability of Bill of Material
Westfield State College
Production & operations Management
9 - 19
Time-Based Competition
(TBC)
• Basic idea: Compete on time, as
well as quality, flexibility, and cost.
• Use of technology (CAD, CAE,
CAM) in TBC
• Extending JIT beyond the factory
floor (to sales, finance, accounting,
etc.)
• Application of TBC in the service
sector
Westfield State College
Production & operations Management