8 – 1 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Lean Systems 8

8 – 2 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Eight Wastes TABLE 8.1 | THE EIGHT TYPES OF WASTE OR MUDA WasteDefinition 1.OverproductionManufacturing an item before it is needed. 2.Inappropriate Processing Using expensive high precision equipment when simpler machines would suffice. 3.WaitingWasteful time incurred when product is not being moved or processed. 4.TransportationExcessive movement and material handling of product between processes. 5.MotionUnnecessary effort related to the ergonomics of bending, stretching, reaching, lifting, and walking. 1.InventoryExcess inventory hides problems on the shop floor, consumes space, increases lead times, and inhibits communication. 1.DefectsQuality defects result in rework and scrap, and add wasteful costs to the system in the form of lost capacity, rescheduling effort, increased inspection, and loss of customer good will. 1.Underutilization of Employees Failure of the firm to learn from and capitalize on its employees’ knowledge and creativity impedes long term efforts to eliminate waste.

8 – 3 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Continuous Improvement with lean system water surface: service capacity (in service) or inventory level (in manufacturing) rock: problems of processes Figure 8.1 – Continuous Improvement with Lean Systems

8 – 4 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Group Technology Drilling DD DD Grinding GG GG GG Milling MM MM MM Assembly AA AA Lathing Receiving and shipping L LL LL LL L (a) Jumbled flows in a job shop without GT cells Figure 8.3 – Process Flows Before and After the Use of GT Cells

8 – 5 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Group Technology (b) Line flows in a job shop with three GT cells Cell 3 LM G G Cell 1 Cell 2 Assembly area A A L M D L L M Shipping D Receiving G Figure 8.3 – Process Flows Before and After the Use of GT Cells

8 – 6 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Value Stream Mapping Figure 8.7 – Selected Set of Value Stream Mapping Icons

8 – 7 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. Value Stream Mapping Figure 8.8 –A Representative Current State Map for a Family of Retainers at a Bearings Manufacturing Company

8 – 8 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall. House of Toyota Highest quality, lowest cost, shortest lead time by eliminating wasted time and activity Just in Time (JIT)  Takt time  One-piece flow  Pull system Culture of Continuous Improvement Jidoka  Manual or automatic line stop  Separate operator and machine activities  Error-proofing  Visual control Operational Stability HeijunkaStandard WorkTPMSupply Chain Figure 8.9 – House of Toyota