运营管理第14版蔡斯ipptchap008

FacilityLayout ChapterEight Copyright 2014byTheMcGraw HillCompanies Inc Allrightsreserved McGraw Hill Irwin LearningObjectives LO8 1 Analyzethecommontypesofmanufacturinglayouts LO8 2 Illustratelayoutsusedinnonmanufacturingsettings 8 2 LayoutDecisions Facilitylayout theprocessofdeterminingplacementofdepartments workgroupswithindepartments workstations machines andstock holdingpointswithinafacilityThisprocessrequiresthefollowinginputs SpecificationoftheobjectivesusedtoevaluatethedesignEstimatesofproductorservicedemandProcessingrequirementsSpacerequirementsfortheelementsSpaceavailabilitywithinthefacility 8 3 BasicProductionLayoutFormats Workcenter job shoporfunctionallayout Similarequipmentaregroupedtogether Assemblyline flow shoplayout Workprocessesarearrangedaccordingtothestepsbywhichtheproductismade ManufacturingcellDissimilarmachinesaregroupedtoworkonsimilarproducts ProjectlayoutProductremainsatonelocation 8 4 Workcenters GivenTheflow numberofmoves toandfromalldepartmentsThecostofmovingfromonedepartmenttoanotherTheexistingorplannedphysicallayoutoftheplantDetermineThe best locationsforeachdepartment wherebestmeansmaximizingflow whichminimizescosts 8 5 Example8 1 ToyFactory Goalistoarrangeeightworkcenterstominimizeinterdepartmentalhandlingcost Assumeallworkcentershavesamespaceandfitinbuilding Allmaterialistransportedinstandardcratesbyforklift Transportationcostsare 1tomovebetweenadjacentworkcenters Extra 1foreachworkcenterinbetween 8 6 Steps Illustratetheinterworkcenterflowbyamodel Determinethecostofthislayout Searchforworkcenterlocationchangesthatwillreducecosts 8 7 Example8 1 InterworkcenterFlow andBuildingDimensionsandWorkcenters 8 8 Example8 1 InterworkcenterFlowGraphwithNumberofAnnualMovements 8 9 Example8 1 CostMatrix FirstSolution 8 10 Example8 1 RevisedInterworkcenterFlowchartandCostMatrix SecondSolution 8 11 SystematicLayoutPlanning NumericalflowofitemsbetweenworkcentersCanbeimpracticaltoobtainDoesnotaccountforthequalitativefactorsthatmaybecrucialtotheplacementdecisionSystematiclayoutplanningAccountsfortheimportanceofhavingeachdepartmentlocatednexttoeveryotherdepartmentIsalsoguidedbytrialanderrorSwitchingworkcentersthencheckingtheresultsofthe closeness score 8 12 SystematicLayoutPlanningforaFloorofaDepartmentStore 8 13 AssemblyLine Assemblyline progressiveassemblylinkedbysomematerialhandlingdeviceSomeformofpacingispresentandtheallowableprocessingtimeisequivalentforallworkstationsImportantdifferences MaterialhandlingdevicesLineconfigurationPacingProductmixWorkstationcharacteristicsLength 8 14 Assembly LineDesign Workstationcycletime auniformtimeintervalinwhichamovingconveyorpassesaseriesofworkstationsAlsothetimebetweensuccessiveunitscomingoffthelineAssembly linebalancing assigningalltaskstoaseriesofworkstationssothateachworkstationhasnomorethancanbedoneintheworkstationcycletimePrecedencerelationship theorderinwhichtasksmustbeperformedintheassemblyprocess 8 15 Assembly LineBalancing Specifythesequentialrelationshipsamongtasks Determinetherequiredworkstationcycletime Determinethetheoreticalminimumnumberofworkstations Selectaprimaryandsecondaryassignmentrule Assigntasks Evaluatetheefficiencyofthebalance Rebalanceifneeded 8 16 Assembly LineBalancingFormula 8 17 Example8 2 AssemblyStepsandTimes 8 18 Example PrecedenceGraph 8 19 Example CandNt 8 20 Example Assignment 8 21 Example Efficiency 8 22 TaskSplitting SplitthetaskSharethetaskUseparallelworkstationsUseamoreskilledworkerWorkovertimeRedesign 8 23 FlexibleLineLayouts Problem operatorstrappedin cages preventssharingworkamongthem Solution removebarrierssooperatorscantradeworkandoperatorscanbeaddedorremovedasneeded 8 24 FlexibleLineLayouts Problem operators birdcaged withnoopportunitytoshareworkoraddthirdoperator Solution operatorscanhelpeachotherandthirdoperatorcanbeaddedifneeded 8 25 FlexibleLineLayouts Problem straightlineisdifficulttobalance Solution U shapedlinegivesbetteroperatoraccessandmayreduceneedforoperators 8 26 Mixed ModelLineBalancing Mostfactoriesproduceanumberofdifferentproducts Inventorycanbereducedbybuildingsomeofeachproductduringeveryperiod e g day week etc Mixed modellinebalancingisonemeansofschedulingthisvariedproduction 8 27 Example8 3 Mixed ModelLineBalancing ProcessingmustbecompletedforbothModelJandModelKwagons Equalnumberofeachmodelarerequired Cycletime 6minutesforModelJand4minutesforModelK Inan8 hourday howshouldthemodelsbeprocessed BecauseK J wecanproduce48ofeachperday 6ofeachperhour 8 28 Example8 3 Mixed ModelLineBalancing Thisapproachoftenrequiresdiligenteffortstoreducesetuptimesandcosts butcansignificantlyreduceoverallinventorylevels 8 29 DevelopingaManufacturingCell GroupingpartsintofamiliesthatfollowacommonsequenceofstepsIdentifyingdominantflowpatternsofpartsfamiliesasabasesforlocationofprocessesPhysicallygroupingmachinesandprocessesintocells 8 30 Example OriginalWorkcenterLayout 8 31 Example RoutingMatrixBaseduponFlowofParts 8 32 Example ReallocatingMachinestoFormCells 8 33 ManufacturingCellBenefits BetterhumanrelationsImprovedoperatorexpertiseLessin processinventoryandmaterialhandlingFasterproductionsetup 8 34 ProjectLayout Ischaracterizedbyarelativelylownumberofproductionunits Visualizetheproductasthehubofawheelwithmaterialsandequipmentarrangedconcentricallyaroundtheproductionpoint Ahighdegreeoftaskorderingiscommon Totheextentthatthisprecedencedeterminesproductionstages aprojectlayoutmightbedevelopedbyarrangingmaterialsaccordingtotheirtechnologicalpriority 8 35 RetailServiceLayout Goal maximizenetprofitpersquarefootoffloorspaceServicescapesAmbientconditionsBackgroundcharacteristics suchasnoiseSpatiallayoutandfunctionalityPlanningthecirculationpathofcustomersandgroupingmerchandiseSigns symbols andartifactsPartsoftheservicethathavesocialsignificance 8 36 AlternativeStoreLayouts 8 37 MarketingResearchandRetailLayout 8 38 Peopleinsupermarketstendtofollowaperimeterpatternintheirshoppingbehavior Placinghigh prof