Presentation on theme: "Just-In-Time and Lean Systems"— Presentation transcript:
1 Just-In-Time and Lean Systems Chapter 7Just-In-Time and Lean Systems
2 Just-In-Time (JIT)Getting the right goods to the right place at the right time.In an ideal JIT system, inventory = ??JIT is a goal and a philosophy.
3 Lean System: A Broad View of JIT Extending JIT philosophy to the entire organization, it is the Lean System.In a lean system, everything is “right”, therefore no waste existing.
4 What are “Wastes”?Waste is anything that doesn’t add value: time, money, resource, material, space, energy, labor activity, …What may cause wastes?InventoryUnsynchronized productionUnstreamlined layoutsUnnecessary material handlingScrap & rework…
5 Central Beliefs of Philosophy of JIT / Lean System Elimination of wasteBroad view of operationsSimplicityContinuous improvementVisibilityFlexibility
6 Eliminate WasteAnything in an operation that does not add value is waste.Method A and method B can both get a task done. If A can do it better, or faster, or in a cheaper way, then there exist wastes in method B.
7 Everyone Has a Broad View of Organization Instead of focusing on the assigned jobs only, a worker has a broad view of the organization: its mission and goals, and place his job in that big picture.
8 SimplicityIf a problem can be solved in a simple way, do not go complicate.
9 Continuous Improvement Good enough is not good enough.“Kaizen blitz” is a Japanese way of implementing continuous improvement idea. It is a few day’s intensive work of a cross-functional team aiming at resolving a bite-size chunk of a problem.
10 Visibility Visibility is to make waste visible. Waste can only be eliminated after it’s discovered.Clutter and inventory hide waste.JIT requires clean facilities and open space so that no waste can be hidden.
11 FlexibilityFlexible so as to adapt to changes in the demand and environment.Volume flexibilityVariety flexibility
12 Three Elements that Make JIT Work Just-in-time manufacturingTotal quality managementRespect for people
13 JIT Manufacturing Kanbans & pull production systems Quick setups & small lotsUniform plant loadingFlexible resourcesEfficient facility layouts
14 Pull ProductionProcess is driven by real demands (rather than demand forecasts).Doing nothing unless a real demand calls (demand pull).All work stations are “demand pull”.
15 Kanban Production System A “pull production” system.Real demand information is passed in relay backward from the last work station by using ‘kanbans (cards)’.Each work station works according to the kanbans passed from the next station.Each work station is responsible to pass proper kanbans to the previous station.
19 Number of Kanbans in a Withdraw Work Station N = number of containers in a withdraw stationD = demand rate at the withdraw stationT = lead time from supply stationC = container sizeS = safety stock to protect against uncertainty
20 Quick Setups & Small Lots Setup times = time required to get the machine readycleaning, calibrating, changing tools, ...Internal setupsThe machine must stop when doing setup.External setupsSetup can be performed when machine is running.
21 Uniform Plant Loading“Leveling” of the production schedule so that the production of a product is evenly spread over the planning horizon in small batches.Leveling the schedule can have big impact along whole supply chain.
23 Flexible Resources General purpose equipment: Multifunctional workers: E.g.: drills, lathes, printer-fax-copiers, etc.Capable of being setup to do many different thingsMultifunctional workers:Cross-trained to perform several different duties
24 Efficient Facility Layouts Workstations in close physical proximity to reduce transport & movementStreamlined flow of materialOften uses:Cellular Manufacturing (instead of job shops)U-shaped lines: (allows material handler to quickly drop off materials & pick up finished work)
25 Cellular Manufacturing (Group Technology) Components are grouped according to their similarities.Machines are grouped in cells so that a cell can complete the processing of some groups of componentsSimilar components are processed completely in a cell composed of dissimilar machines.
28 TQM & JIT Quality at the Source Jidoka (authority to stop line) Poka-yoke (foolproof the process)Preventive maintenance
29 Respect for People: The Role of Workers Cross-trained workersActively engaged in problem-solvingWorkers are empoweredEveryone responsible for qualityWorkers gather performance dataTeam approaches used for problem-solvingDecision made bottom-upWorkers responsible for preventive maintenance
30 Respect for People: The Role of Management Responsible for culture of mutual trustServe as coaches & facilitatorsSupport culture with appropriate incentive systemResponsible for developing workersProvide multi-functional trainingFacilitate teamwork
31 Supplier Relations & JIT Use single-source suppliersBuild long-term relationshipsCo-locate facilities to reduce transportStable delivery schedulesShare cost & other information
32 Benefits of JIT Smaller inventories Improved quality Reduced space requirementsShorter lead timesLower production costsIncreased productivityIncreased machine utilizationGreater flexibility
33 Implementing JIT Manufacturing Identify & fix problemsReorganize workplaceRemove clutter & designate storageReduce setup timesReduce lot sizes & lead timesImplement layout changesCellular manufacturing & close proximitySwitch to pull productionExtend methods to suppliers