Presentation on theme: "Lean Manufacturing & Just-in-Time"— Presentation transcript:
1Lean Manufacturing & Just-in-Time "The most dangerous kind of waste is the waste we do not recognize." - Shigeo Shingo
2Reducing Waste: Push versus Pull System Material FlowInformation FlowFGICustomerRawMaterialSupplierFinalAssemblyPUSHFGICustomerRawMaterialSupplierFinalAssemblyPULL
3Push SystemEvery worker maximizes own output, making as many products as possiblePros and cons:Focuses on keeping individual operators and workstations busy rather than efficient use of materialsVolumes of defective work may be producedThroughput time will increase as work-in-process increases (Little’s Law)Line bottlenecks and inventories of unfinished products will occurHard to respond to special orders and order changes due to long throughput time
4Pull SystemProduction line is controlled by the last operation, Kanban cards control WIPPros and consControls maximum WIP and eliminates WIP accumulating at bottlenecksKeeps materials busy, not operators. Operators work only when there is a signal to produce.If a problem arises, there is no slack in the systemThroughput time and WIP are decreased, faster reaction to defects and less opportunity to create defects
5Features of Lean Production Management philosophy“Pull” system though the plantWHAT IT ISAttacks wasteExposes problems and bottlenecksAchieves streamlined productionWHAT IT DOESStable environmentWHAT IT ASSUMESEmployee participationIndustrial engineering/basicsContinuing improvementTotal quality controlSmall lot sizesWHAT IT REQUIRESKaizen13
6A Little History! Ford: Design for manufacturing Start with an article that suits and then study to find some way of eliminating the entirely useless parts. This applies to everything— a shoe, a dress, a house, a piece of machinery, a railroad, a steamship, an airplane. As we cut out useless parts and simplify necessary ones, we also cut down the cost of making. ...But also it is to be remembered that all the parts are designed so that they can be most easily made."
7A Little History! Ohno – put ideas into practice systematically “When bombarded with questions from our group on what inspired his thinking, Ohno just laughed and said he learned it all from Henry Ford's book."
8TPS: Toyota Production System A system that continually searches for and eliminates waste throughout the value chain.Views every enterprise activity as an operation and applies its waste reduction concepts to each activity - from Customers to the Board of Directors to Support Staff to Production Plants to Suppliers.
10Elimination of Waste 5S Group technology Quality at the source JIT productionKanban production control systemMinimized setup timesUniform plant loadingFocused factory networks6
11Minimizing Waste – 5S Japanese Translation English Seiri “Good factories develop beginning with the 5S’s. Bad factories fall apart beginning with the 5 S’s.”- Hirouki HiranoJapaneseTranslationEnglishSeiriProper arrangementSortSeitonOrderlinessSimplifySeisoCleanlinessSweepSeiketsuCleanupStandardizeShitsukeDisciplineSustain
12Minimizing Waste – 5SA place for everything and everything in its placeNot just a housekeeping issueCritical foundation forSetup reductionPull systemsMaintenanceInventory management
13Minimizing Waste: Group Technology Using Departmental Specialization (Job Shop) for plant layout can cause a lot of unnecessary material movementNote how the flow lines are going back and forthSawSawSawGrinderGrinderHeat TreatLatheLatheLathePressPressPress8
14Minimizing Waste: Group Technology Revising by using Group Technology Cells can reduce movement and improve product flowGrinder12LathePressSawLatheHeat TreatGrinderABLathePressSawLathe9
15Minimizing Waste: JIT ??? Only produce what’s needed The opposite of “Just In Case” philosophyIdeal lot size is oneMinimize transit timeFrequent small deliveries???Pro’sMinimal inventoryLess spaceMore visualEasier to spot quality issuesCon’sRequires disciplineRequires good problem solvingSuppliers or warehouses must be closeRequires high quality
19Minimizing Waste – Kanban Signaling device to control flow of materialCardsEmpty containersLightsColored golf ballsEtc
20Minimizing Waste – Setup Times Long setup times drive:Long production runsLarge lotsLong lead timesJIT requires small lots and minimum kanbansSetup reductionFocused effortsProblem solvingFlexible equipment
21Minimizing Waste – Plant Loading HeijunkaSuppose we operate a production plant that produces a single product. The schedule of production for this product could be accomplished using either of the two plant loading schedules below.Not uniform Jan. Units Feb. Units Mar. Units Total1,200 3,500 4,300 9,000orUniform Jan. Units Feb. Units Mar. Units Total3,000 3,000 3,000 9,000How does the uniform loading help save labor costs?12
22Minimizing Waste – Focused Factory Networks These are small specialized plants that limit the range of products produced (sometimes only one type of product for an entire facility)CoordinationSystem Integration7
23TPS – Respect for People Level payrollsCooperative employee unionsSubcontractor networksBottom-up management styleQuality circles (Small Group Problem Solving)Keiretsu21
24TPS – 4 RulesAll work shall be highly specified as to content, sequence, timing, and outcomeEvery customer-supplier connection must be direct, and there must be an unambiguous yes-or-no way to send requests and receive responsesThe pathway for every product and service must be simple and directAny improvement must be made in accordance with the scientific method, under the guidance of a teacher, at the lowest possible level in the organization21
26Summary and Conclusions… Lean Production is the set of activities that achieves quality production at minimum cost and inventoryThe flow of material is pulled through the process by downstream operationsLean originated with the Toyota Production System and its two philosophies – elimination of waste, and respect for peopleCLOSED MITT forms of waste