TÀI LIỆU ÔN THI QTSX Toyota Production System and Lean Manufacturing

Toyota Production System and Lean Manufacturing D Jorge Leon Texas A&M University TOYOTA PRODUCTION SYSTEM The Toyota Production System was adopted by many Japanese companies in the aftermath of the 1973 oil shock “Waste” Elimination Philosophy: “ Above all, one of our most important purposes was increased productivity and reduced cost To achieve this purpose, we put our emphasis on the notion of eliminating all kinds of unnecessary functions in the factories Our approach has been to investigate one by one the causes of various "unnecessaries" in manufacturing operations and to devise methods for their solution, often by trial and error ” Taiicho Ohno, Former Vice President, Toyota Motor Corp., Former President, Japan Industrial Management Association; Former Chairman, Toyoda Spinning and Weaving Co., Ltd PURPOSES OF JIT Primary Purpose: Profit through cost reduction (or improvement of Productivity) This is attained through WASTE elimination Other important purposes: Quantity control: JIT, Kanban & Autonomation (visual control system) Quality control: Autonomation, improvement by small groups, functional management Respect for humanity : Flexible work force (adapt to demand changes), capitalize workers ideas TYPES OF WASTE Excessive production resources (primary waste): excessive workforce excessive facilities excessive inventories unnecessary capital investment Overproduction (secondary waste - the WORST waste): leads to Excessive inventories (tertiary waste): extra jobs make overproduction invisible adds losses in opportunity cost lead to Unnecessary capital investment (fourth waste): adds facility depreciations and overhead cost TO ACHIEVE THESE PUPOSES Wastes Elimination Just-In-Time (JIT) Production Kanban System Production Smoothing 5S Setup Time Reduction Machine Layout & Multi-function Worker Autonomation (Visual Management) 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Identification and Elimination of Waste Philosophy • Identification and elimination of waste is the central theme of a lean manufacturing production system • Lean manufacturing is a dynamic and constantly improving process dependent upon understanding and involvement by all employees • Successful implementation requires that all employees must be trained to identify and eliminate waste from their work • Waste exists in all work and at all levels in the organization 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Identification and Elimination of Waste Philosophy Effectiveness is the result of the integration of: - Man - Method - Material - Machine At the worksite • Waste exists in all work and at all levels in the organization 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Seven Types of Waste Over-production Wait time Transportation Processing Inventory Motion Defects 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Over-production Waste Definition Producing more than needed Producing faster than needed 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Over-production Waste Characteristics: • • • • • • • • • • • • • Inventory Stockpiles Extra equipment/oversized equipment Unbalanced Material Flow Extra Part Storage racks Extra Manpower Batch Processing Complex Inventory Management Excessive Capacity/Investment Additional Floor Space/Outside Storage Hidden Problems Excessive Obsolescence Large Lot Sizes Building Ahead 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Over-production Waste Causes: • Incapable Processes • Just in Case Reward System • Lack of Communication • Local Optimization • Automation in the Wrong Places • Cost Accounting Practices • Low Uptimes • Lack of Stable/Consitent Schedules 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Waiting Time Waste Definition Idle Time That is Produced When Two Dependant Variables are not Fully Synchronized • Man Wait Time • Machine Wait Time 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Waiting Time Waste Characteristics: • Man Waiting for Machine • Machine/Materials Waiting for Man • Unbalanced Operations (Work) • Lack of Operator Concern for Equipment Breakdowns • Unplanned Equipment Downtime 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Waiting Time Waste Causes: • Inconsistent Work Methods • Long Machine Change Over Time • Low Man/Machine Effectiveness • Lack of Proper Equipment/Materials 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Transportation Waste Definition Any Material Movement That Does Not Directly Support a Lean Manufacturing System 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Transportation Waste Characteristics: • Extra carts, fork lifts, dollies • Multiple Storage Locations • Extra Material Racks • Complex Inventory Management • Extra Facility Space • Incorrect Inventory Counts • Damaged Material 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Transportation Waste Causes: • Large Lot Processing • Unleveled Schedules • Lack of S’s • Lack of Visual Controls • Improper Facility Layout • Large Buffers and In Process Kanbans 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Processing Waste Definition Effort Which Adds No Value To a Product or Service Enhancements which are Transparent to The Customers or Work Which Could Be Combined with Another Process 10 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Processing Waste Characteristics: • Process Bottlenecks • Lack of Clear Customer Specifications • Endless Refinement • Redundant Approvals • Extra Copies/Excessive Information 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Processing Waste Causes: • Engineering Changes Without Processing Changes • Decision Making at Inappropriate Levels • Inefficient Policies and Procedures • Lack of Customer Input Concerning Requirements 11 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Inventory Waste Definition Any Supply in Excess of Process Requirements Necessary to Produce Goods or Services Just in Time 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Inventory Waste Characteristics: • Extra Space on Receiving Docks • Material Between Processes • Stagnated Material Flow • LIFO instead of FIFO • Extensive Rework When Problems Surface • Long Lead Time for Engineering Changes • Additional Material Handling Resources (Men, Equipment, Racks, Storage Space) 12 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Inventory Waste Causes: • Incapable Processes • Uncontrolled Bottleneck Processes • Incapable Suppliers • Long Change Over Times • Management Decisions • Local Optimization • Inaccurate Forcasting Systems Inventory Level Over Production Wait Time Process Defects 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Motion Waste Definition Any Movement of People Which Does Not Contribute Added Value To The Product or Service 13 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Motion Waste Characteristics: • Looking for Tools • Excessive Reaching or Bending • Material Too Far Apart (Walk Time) • Equipment for Moving Parts • Extra “Busy” Movements While Waiting 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Motion Waste Causes: • Equipment, Office & Plant Layout • Lack of S’s • Lack of Visual Controls • Inconsistent Work Methods (Standardized Work) • Large Batch Sizes 14 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Rework or Correction Waste Definition Repair of a Product or Service To Fulfill Customer requirements 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Rework or Correction Waste Characteristics: • Extra Floor Space/Tools/Equipment • Extra Manpower To Inspect/Rework/Repair • Stockpiling Inventory • Complex Material Flow • Questionable Quality • Missed Shipments/Deliveries • Lower Profits Due To Scrap • Reactive Organization 15 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Rework or Correction Waste Causes: • Incapable Processes • Excessive Variation • Incapable Suppliers • Management Decisions • Insufficient Training • Inadequate Tools/Equipment • Poor Layouts/Unnecessary Handling • High Inventory Levels 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Seven Types of Waste Over-production Wait time Transportation Processing Inventory Motion Defects 16 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Seven Types of Waste 17 ... Production Smoothing 5S Setup Time Reduction Machine Layout & Multi-function Worker Autonomation (Visual Management) 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing,... Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Transportation Waste Definition Any Material Movement That Does Not Directly Support a Lean Manufacturing... at all levels in the organization 77 Wastes, Wastes, Applied Applied Material’s, Material’s, Lean Lean Manufcaturing, Manufcaturing, Supplier Supplier Copy, Copy, 1999 1999 Identification and