Just-in-time and lean systems.pdf

Just-in-timeandleansystemsJust-in-time(JIT)isoneofthewidelyadoptedandpracticedphilosophyaswellastechnique.•Inthemid1950s,ToyotamanagementstudiedmassproductionintheUSandfound:•Theroomofcuttingggdowncostsoutweighedthebenefitsbroughtbyscale•ustomedtomarketchanges,noremployees’creativityencouraged.•JITenabledJapantotaptheautomobilemarketintheUSin1980sTheJapanesePhilosophyWasteisanythingthatdoesnotaddvaluefromthecustomerpointofviewStorage,inspection,delay,waitinginqueues,anddefectiveproductsdonotaddvalueandare100%wastePullsystemvspushsystemDemandCustomersFinishedproducts“pull”FactoryFinishedproductswarehouseFactoryWork-in-ponents“push”PullsystemApullsystemusessignalstorequestproductionanddeliveryfromupstreamstationsUpstreamstationsonlyproducewhensignaledBypullingmaterialinsmalllots,inventorycushionsareremoved,exposingproblemsandemphasizingcontinualimprovementAdvantagesofKanbanAllowonlyyylimitedamountoffaultyordelayedmaterialProblemsareimmediatelyevidentPutsdownwardpppressureonbadaspectsofinventoryStandardizedcontainersreduceweight,disposalcosts,wastedspace,andlaborPullsystemvspushsystemEssentiallyJITisa‘pull’conceptwheredemanddeterminestheflow.Thetraditionalpushsystemworkswhereproductsaremanufacturedorassembledinanticipationofdemandandarepositionedinthesupplychainas“buffers”betweenvariousfunctions.