Transcript Lean Operations - Georgia Institute of Technology

Lean Operations
“Eliminate Waste
Through
Continuous Improvement”
TPS: Toyota Production System
 A system that continually searches for and
eliminates waste throughout the value chain.
 Views every enterprise activity as an operation and
applies its waste reduction concepts to each
activity - from Customers to the Board of Directors
to Support Staff to Production Plants to Suppliers.
Reducing Waste: Push versus Pull System
Raw
Material
Supplier
Final
Assembly
Customer
FGI
PUSH
Raw
Material
Supplier
Final
Assembly
Customer
FGI
PULL
Information Flow
Material Flow
TPS System uses Kanbans
Penville Game
 Compare the performance of
 Push system
 Pull system
 Team system
Push System
 Every worker maximizes own output, making as
many products as possible
 Pros and cons:
 Focuses on keeping individual operators and workstations
busy rather than efficient use of materials
 Volumes of defective work may be produced
 Throughput time will increase as work-in-process
increases (Little’s Law)
 Line bottlenecks and inventories of unfinished products
will occur
 Hard to respond to special orders and order changes due
to long throughput time
Pull System
 Production line is controlled by the last operation,
Kanban cards control WIP
 Pros and cons
 Controls maximum WIP and eliminates WIP
accumulating at bottlenecks
 Keeps materials busy, not operators. Operators work only
when there is a signal to produce.
 If a problem arises, there is no slack in the system
 Throughput time and WIP are decreased, faster reaction
to defects and less opportunity to create defects
Team System
 Group of cross-trained workers have overlapping
responsibility
 Pros and cons:
 Cross-training and team efforts reduces WIP or the
bottleneck concept
 Most efficient use of both materials and labor
 Cross training means one worker can step out if a
problem arises
 Higher process responsibility and ownership
 Cross training can be costly