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Week 14A – Lean Systems (Chapter 16). Production Environments; Lean Operations (“JIT”) History, Goals and Building Blocks; Maintenance. Production Environments. Product Characteristics (continuum) Customized <--------------> Commodity Operation Types (continuum) Project ¯|¯
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Week 14A – Lean Systems(Chapter 16) Production Environments; Lean Operations (“JIT”) History, Goals and Building Blocks; Maintenance SJSU Bus 140 - David Bentley
Production Environments • Product Characteristics (continuum) • Customized <--------------> Commodity • Operation Types (continuum) • Project ¯|¯ • Batch or Job | • Repetitive/Assembly | • Continuous flow _|_ SJSU Bus 140 - David Bentley
History of Lean Operations (“JIT”) • Japanese Post-WW II conditions • Emphasis on quality and eliminating waste • Also called “lean manufacturing” or the “Toyota production system” • U.S. attention as a result of oil embargo • Change in philosophy needed in U.S. • Also called “Zero Inventory” in U.S. SJSU Bus 140 - David Bentley
Obstacles to “JIT” in the US • Emphasis on MRP systems • Fit job shops most closely • APICS, Oliver Wight and others • Cost Accounting • Traditional job accounting • Management • Reluctance to empower employees • Focus on high utilization • Limited allowance for training SJSU Bus 140 - David Bentley
Key Contributors to “JIT” - 1 • Japan (developer) • TaichiOhno (Toyota Motor Company) • Toyota Production System • Aka Lean Production or Lean Manufacturing SJSU Bus 140 - David Bentley
Key Contributors to “JIT” - 2 • US (popularizers) • RichardSchonberger (U of Nebraska, U of Washington) • Emphasized concepts, management aspect • “Japanese Manufacturing Techniques” • “World Class Manufacturing” • RobertHall (U of Indiana) • Emphasized specific tools and techniques • “Zero Inventories” SJSU Bus 140 - David Bentley
Lean Operations Goals • Eliminate waste • Smooth the flow • Minimize disruptions • Minimize inventory • Reduce queue, setup, wait, transit times • Reduce lead time • Introduce flexibility • Reduce cost SJSU Bus 140 - David Bentley
Lean Operations Requirements • Management commitment • Quality • Training • Worker involvement / ownership • Flexibility - people and equipment • Process changes • Supplier partnerships SJSU Bus 140 - David Bentley
Building Blocks - 1 • Product design • Standard parts • Modular design • Capable production systems SJSU Bus 140 - David Bentley
Building Blocks - 2 • Process design • Quality improvement • Small lot sizes • Setup time reduction • Manufacturing cells • Limited WIP • Production flexibility • Minimal inventory storage SJSU Bus 140 - David Bentley
Building Blocks - 3 • People • View employees as assets • Cross-training • Commitment to continuous improvement • Cost accounting (big obstacle in U.S. due to job costing bias) • Leadership SJSU Bus 140 - David Bentley
Building Blocks - 4 • Manufacturing planning and control • Level loading • Pull systems • Visual signals (Kanban) • Container, card(s), cart, taped space on floor or counter, colored lights (??), golf balls (??) • Supplier partnerships • Reduced transaction processing • Preventive maintenance and housekeeping SJSU Bus 140 - David Bentley
Making the change • Insure true management commitment • Provide employees training • Focus on internal operations before moving on to suppliers • Start small (one line) and at end of process • Deal with cost accounting issues early • Now extend to your suppliers SJSU Bus 140 - David Bentley
Determining the Number of Kanban Containers • Number of containers = DLT + SS ------------ Container size • Example: Demand = 400 per day; Lead Time = 2 days; Safety stock = 100; container size = 90 Number of containers = (400)(2) + 100 ---------------- = 10 90 SJSU Bus 140 - David Bentley