Lean Production

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Chapter 12
Lean Production Just-in-Time
JIT Defined The Toyota Production System JIT
Implementation Requirements JIT in Services
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Just-in-Time (JIT)

• JIT is a philosophy of operations management that
  seeks to eliminate waste in all aspects of a
  firms production activities
• (also called Lean Production)

• JIT relies on a pull system.
• Supplies and components are pulled through
  system to arrive where they are needed when they
  are needed.

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Waste in Operations

• Waste from overproduction
• Waste of waiting time
• Transportation waste
• Inventory waste
• Processing waste
• Waste of motion
• Waste from product defects

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Elements of Waste Reduction

• Minimize waste thru
• Focused Factory Networks
• Flow Lines, based on Group Technology
• Quality at the Source
• Uniform Plant Loading
• Minimized Setup Times and Small Lot Sizes
• JIT production
• Pull System, using Kanban

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Push versus Pull Systems

• Push system material is pushed into downstream
  workstations by the schedule, regardless of
  whether it is needed.
• Pull system material is pulled to a workstation
  by a signal (kanban) from the user to the
  supplier, just as it is needed.

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JIT Demand-Pull Logic
The customer starts the process, pulling an
inventory item from Final Assembly
Then sub-assembly work is pulled forward by that
demand
The process continues throughout the entire
production process and supply chain
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Kanban

• Japanese word for card
• Pronounced kahn-bahn (not can-ban)
• Downstream operations authorize more production
• Material is pulled through the operations by a
  signal from the user to the supplier
• Reduces Inventory (queue limitation)

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Inventory Waste Reduction I
Inventory level (hides problems)
Capacity Imbalances
Unreliable Vendors
Scrap
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Inventory Waste Reduction II
Reducing inventory revealsproblems so they can
be solved.
Unreliable Vendors
Capacity Imbalances
Scrap
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Implementing JIT

• Design a Flow Process
• Use Total Quality Control
• Stabilize the Schedule
• Install a Pull System-Kanban
• Work with Vendors
• Reduce Inventory more
• Improve Product Design

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End of Chapter 12