Lean SystemsHow Lean Systems fits the Operations Management PhilosophyToyota Production System (TPS)Slide 4Slide 5Push and Pull Systems of Work FlowSlide 7Quality at the SourceSlide 9Small Lot SizesSlide 11Uniform Workstation LoadsSlide 13Line Flows and AutomationSlide 15Five S (5S)Slide 17Slide 18The Single-Card Kanban SystemSlide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Slide 27Calculations for Example 9.1Calculations for Example 9.1Application 9.1Value Stream MappingSelected Set of Value Stream Mapping IconsSlide 33Organizational ConsiderationsProcess Considerations Inventory & Scheduling© 2007 Pearson EducationLean SystemsLean SystemsChapter 9Chapter 9© 2007 Pearson EducationHow Lean Systems fits the Operations Management Philosophy Operations As a Competitive WeaponOperations StrategyProject ManagementProcess StrategyProcess AnalysisProcess Performance and QualityConstraint ManagementProcess LayoutLean SystemsSupply Chain StrategyLocationInventory ManagementForecastingSales and Operations PlanningResource PlanningScheduling© 2007 Pearson EducationToyota Production System (TPS)Toyota Production System (TPS) is one of the most admired lean manufacturing systems in existence. They have a process of continuous improvement.Work is completely specified as to content, sequence, timing, and outcome.Services and goods do not flow to the next available person or machine, but to a specific person or machine.Employees are stimulated to experiment to find better ways to do their jobs.Improvements to the system must be made in accordance with the scientific method, under the guidance of a teacher, at the lowest possible organizational level.© 2007 Pearson EducationLean SystemsLean systems are operations systems that maximize the value added by each of a company’s activities by paring unnecessary resources and delays from them.Just-in-time (JIT) philosophy The belief that waste can be eliminated by cutting unnecessary capacity or inventory and removing non-value-added activities in operations.JIT system: A system that organizes the resources, information flows, and decision rules that enable a firm to realize the benefits of JIT principles.© 2007 Pearson Education-Pull method of work flow-Quality at the source-Small lot sizes-Uniform workstation loads-Standardized components & work methods-Close supplier ties-Flexible workforce-Line flows-Automation-Five S-Preventive maintenanceCharacteristics of Lean Systems© 2007 Pearson EducationPush and Pull Systems of Work FlowPush method: A method in which production of the item begins in advance of customer needs.Example: A buffet where food is prepared in advance.Pull Method: A method in which customer demand activates production of the service or item.Example: A restaurant where food is only prepared when orders are placed.Lean systems use the pull method of work flow.© 2007 Pearson Education-Pull method of materials flow-Quality at the source-Small lot sizes-Uniform workstation loads-Standardized components & work methods-Close supplier ties-Flexible workforce-Line flows-Automation-Five S-Preventive maintenanceCharacteristics of Lean Systems© 2007 Pearson EducationQuality at the SourceQuality at the source is an organization-wide effort to improve the quality of a firm’s products by having employees act as their own quality inspectors, and never pass defective units to next stage.One approach for implementing quality at the source is to use poka-yoke, mistake-proofing methods aimed at designing fail safe systems that minimize human error.Another approach for implementing quality at the source is a practice the Japanese call jidoka, and andon, which gives machines and machine operators the ability to detect when an abnormal condition has occurred.© 2007 Pearson Education-Pull method of materials flow-Quality at the source-Small lot sizes-Uniform workstation loads-Standardized components & work methods-Close supplier ties-Flexible workforce-Line flows-Automation-Five S-Preventive maintenanceCharacteristics of Lean Systems© 2007 Pearson EducationSmall Lot SizesLot: A quantity of items that are processed together.Setup: The group of activities needed to change or readjust a process between successive lots of items.Single-digit setup: The goal of having a setup time of less than 10 minutes.© 2007 Pearson Education-Pull method of materials flow-Quality at the source-Small lot sizes-Uniform workstation loads-Standardized components & work methods-Close supplier ties-Flexible workforce-Line flows-Automation-Five S-Preventive maintenanceCharacteristics of Lean Systems© 2007 Pearson EducationUniform Workstation LoadsA lean system works best if the daily load on individual workstations is relatively uniform.Service processes can achieve uniform workstation loads by using reservation systems (e.g., scheduled surgeries) and differential pricing to manage the demand.For manufacturing processes, uniform loads can be achieved by assembling the same type and number of units each day, thus creating a uniform daily demand at all workstations.Mixed-model assembly produces a mix of models in smaller lots.© 2007 Pearson Education-Pull method of materials flow-Quality at the source-Small lot sizes-Uniform workstation loads-Standardized components & work methods-Close supplier ties-Flexible workforce-Line flows-Automation-Five S-Preventive maintenanceCharacteristics of Lean Systems© 2007 Pearson EducationLine Flows and AutomationLine Flows: Managers of hybrid-office and back-office service processes can organize their employees and equipment to provide uniform work flows through the process and, thereby, eliminate wasted employee time.Another tactic used to reduce or eliminate setups is the one-worker, multiple-machines (OWMM) approach, which essentially is a one-person line.Automation plays a big role in lean systems and is a key to low-cost operations.© 2007 Pearson Education-Pull method of materials flow-Quality at the source-Small lot sizes-Uniform workstation loads-Standardized components & work methods-Close supplier ties-Flexible workforce-Line flows-Automation-Five S-Preventive maintenanceCharacteristics of Lean Systems© 2007 Pearson EducationFive S (5S)Five S (5S) A methodology consisting of five workplace practices conducive to visual controls and lean production.1. Sort: Separate needed from unneeded items (including tools, parts, materials,