瓶颈管理(BottleneckManagement)

2010-10-8SuChun,[e-mail]ttleneckManagementSuChunSuChunSuChun2010-10-8SuChun,SoutheastUniversity2WhatIsBottleneck?2010-10-8SuChun,SoutheastUniversity3WhatIsBottleneck?2010-10-8SuChun,SoutheastUniversity4WhatIsBottleneck?zAbottleneckisaphenomenonwhenwaterorliquidispouredoutofabottle,therateofoutflowortheflowspeedislimitedbythewidthofitsneck-thatis,bottleneck.zAsweknowthatincreasethewidthofthebottleneck,youcanincreasetherateofwhichthewaterflowsout.zThetermbottleneckismetaphoricallyderivedfromthebottleneckofabottle.Forasystem,theperformanceorcapacityofanentiresystemislimitedbyasingleorlimitednumberofcomponentsorresources.zPertainingtoabusiness,afirmwilladdressthe'bottleneck'thatislimitingproduction.——FromWikipedia2010-10-8SuChun,SoutheastUniversity5WhatIsBottleneck?zAbottleneckinprojectmanagementisoneprocessinachainofprocesses,suchthatitslimitedcapacityreducesthecapacityofthewholechain.Thecomponentissometimescalledabottleneckpoint.zThroughputTimeisthetotaltimefromthestarttothefinishofaprocess.Abottleneckistheprocessorstepwhichhasthelowestcapacityandlongestthroughput.zBottleneckscanbeinternalorexternaltoafirm.2010-10-8SuChun,SoutheastUniversity6WhatIsBottleneck?Metaphoricallyabottleneckisasectionofaroutewithacarryingcapacitysubstantiallybelowothersectionsofthesameroute.Thisisoftenanarrowpartofaroad,perhapsalsowithasmallernumberoflanes,orareductionofthenumberoftracksofarailwayline.Itmaybeduetoanarrowbridgeortunnel,adeepcuttingornarrowembankment,orworkinprogressonpartoftheroadorrailway.2010-10-8SuChun,SoutheastUniversity7WhatIsBottleneck?2010-10-8SuChun,SoutheastUniversity8WhatIsBottleneck?2010-10-8SuChun,SoutheastUniversity9WhatIsBottleneck?2010-10-8SuChun,SoutheastUniversity10WhatIsBottleneck?2010-10-8SuChun,SoutheastUniversity11WhatIsBottleneck?zEverysystemwasbuiltforapurposeandhasasystem’sglobalgoal.zSoactionsofanddecisionaboutthesubsystemsmustbejudgedonimpacttowardstheglobalgoal.zAnythingthatlimitsasystemfromachievinghigherperformancevsitsgoal,itcanbecalledbottleneckorconstraint.zSobottleneckistheconstraintthatiscurrentlylimitingthesystem.2010-10-8SuChun,SoutheastUniversity12WhatIsBottleneck?WoodenBarrelTheoryShortBoardEffectThecapacity(containingwater)ofabarrelisdeterminednotbythelongestpieceofwood,butitdependsontheshortestpieceofwood.2010-10-8SuChun,SoutheastUniversity13WhatIsBottleneck?•JosephSchumpeter1883-19502010-10-8SuChun,SoutheastUniversity14WhatIsBottleneck?ChainTheoryThestrengthofanychainisdependantuponitsweakestlink.2010-10-8SuChun,SoutheastUniversity15WhatIsBottleneck?Ittakes10+20+max(15,12)+5+10=60minutestocompletealoanapplication.UnlessmoreresourcesareaddedatstepB,thebankwillbeabletocompleteonly3loanaccountsperhour,or15newloadaccountsinafive-hourday.1.Checkloandocumentsandputtheminorder(10minutes)2.Categorizeloans(20minutes)3.Checkforcreditrating(15minutes)6.Completepaperworkfornewloan(10minutes)4.Enterloanapplicationdataintothesystem(12minutes)Customer5.Isloanapproved?(5min)YesNoBottleneckHowmanycustomerscanthebankcanprovideforserviceperhour?2010-10-8SuChun,SoutheastUniversity16ProductionSystemBasically,thegoalofaProductionSystemistomakemoney!!!2010-10-8SuChun,SoutheastUniversity17ProductionSystemPerformanceMeasurementofaProductionSystem——FinancialzNetprofit–anabsolutemeasurementinmoneyzReturnoninvestment–arelativemeasurebasedoninvestmentzCashflow–asurvivalmeasurement2010-10-8SuChun,SoutheastUniversity18ProductionSystemPerformanceMeasurementofaProductionSystem:——OperationalzThroughputTherateatwhichmoneyisgeneratedbythesystemthroughsaleszInventoryAllthemoneythatthesystemhasinvestedinpurchasingthingsitintendstosellzOperatingexpensesAllthemoneythatthesystemspendstoturninventoryintothroughput2010-10-8SuChun,SoutheastUniversity19ProductionSystem•MaximizeThroughput•MinimizeInventory•MinimizeOperatingExpense•Alltheabovegoalsbeachievedatthesametime.•ToSumuptheGoalistoMAKEMONEYTheGoalofaProductionSystemis:2010-10-8SuChun,SoutheastUniversity20BottleneckinProductionSystemABCDEMarketDemandGenerally,anyproductionsystemcanbesimplifiedtoacertainkindofnetwork.2010-10-8SuChun,SoutheastUniversity21BottleneckinProductionSystemWhenoneprocesstakeslongerthantheaverage,thetimecannotbemadeup,theflowofproductthroughthesystemwillbeunbalancedProcessTime(B)10(Constant)ProcessTime(A)6810(Variable)ProcessTime(A)6810(Variable)ProcessTime(B)10(Constant)Or2010-10-8SuChun,SoutheastUniversity22BottleneckinProductionSystem•WhatisaBottleneck?–Anyfactorthatlimitssystemperformanceandrestrictsitsoutput.•Capacityistheavailabletimeforproduction•Bottleneckiswhathappensifcapacityislessthandemandplacedonresource.•Nonbottleneckiswhathappenswhencapacityisgreaterthandemandplacedonresource.•Capacity-constrainedresource(CCR)isaresourcewherethecapacityisclosetodemandplacedontheresource.2010-10-8SuChun,SoutheastUniversity23BottleneckinProductionSystemWhataretheconsequencesofsavingtimeateachprocess?Whataretheconsequencesofsavingtimeateachprocess?•Rule1:Bottlenecksgovern