SOCIETYOFAUTOMOTIVE ENGINEERS, INC. TwoPennsylvania Plaza,NewYork,N.Y.10001 AnApproachTowardOptimizing MaterialCostandPartFunction inAdvancedPowerplants R.W.Stusrud, E.S.Nichols,B.A.Zolezzi,andD.K.Hanink DetroitDieselAllison,Div.,GeneralMotorsCorp. NationalAerospaceEngineering andManufacturing Meeting LosAngeles,California October16-18,1973730909 Downloaded from SAE International by University Of Newcastle, Wednesday, August 08, 2018730909 AnApproachTowardOptimizing MaterialCostandPartFunction inAdvancedPowerplants R.W.Stusrud,E.S.Nichols,B.A.Zolezzi,andD.K.Hanink DetroitDieselAllison,Div.,GeneralMotorsCorp. ANENTIRELY NEWWAYofthinkingwithrespecttoad vancedmilitaryengineshasdevelopedinordertorespondto theU.S.Department ofDefense'scriticalproblemofsharply increasingcostsofadvancedtechnology weaponsandtrans portationsystems.Tradeoffsarenowbeingconductedbe tweenenginecostandperformance capability. Advanced technology featuresarebeingrejectedfromenginedesigns whentheircostsarefoundtobeout-of-line. Therehasbeenstrongmanagement supportwithinDetroit DieselAllison(DDA)inthisefforttocontrolcostsonnew militaryenginestightly.Therearegoodreasonsforthisat titude,andithasmadeitselffeltthroughout thedivision,so thateffectiveandcooperative workingrelationships havebeen established inalldepartments whereparticipation isneeded. Fig.1showshowanAdvancedTechnology CostReduction Committee hasbeenformedwithintheexistingorganization. Italsoshowstheoperational departments represented onthe committee. Engineering, manufacturing, plantengineering, qualitycontrol,purchasing andfinancialdepartments areall represented bymanagement personnel. Intheengineering department, twobasicapproaches havebeenused.Thefirsthasprovedusefulinthepreliminary de signphasewherealargenumberofenginescanbeevaluated withaminimumoftimeandexpense.Thesecondisamore comprehensive anddetailedanalysisappliedtoenginesinthe detaileddesignordevelopment phases. PRELIMINARY DESIGNENGINES/MATERIALS INDEX FACTOR Theapproachwehavefoundsuccessfulforcostreduction studiesinearlystagesofenginecycleselectionandpreliminary designreliesonanindexfactorwhichisdetermined bythe weightintheengineofmaterialsofseveraldifferentcomposi tionclassifications. Thismaterialsindexfactor(MIF)hasbeen derivedfromworkinthisfieldbypersonneloftheNavalAir Development CenterandwasdisclosedbyT.J.Brennanand othersin1970(1)* InthesestudiesattheNavalAirDevelopment Center,thrust, *Numbers inparentheses designateReferences atendof paper. ABSTRACT Thispaperdescribestherecentandsuccessfulfeaturesofthe intensiveprogramatDetroitDieselAllison,DivisionofGMC, tocontrolthecostsofadvancedmilitaryaircraftgasturbine enginesinlinewiththecostsofcurrentproduction engines andofthoseproducedduringthepastseveralyears.Wehave beenattempting toincorporate highlyadvancedtechnology intoournewproducts,whileatthesametimeholdingthe costsinlinewitholdertechnology products. Inmanyinstances,wehavebeenabletousetheadvancedtechnology to lowercostsatthesametimethatweightandperformance are improved. Thereareexamplesofthisinaerodynamics, me chanicaldesign,andmaterialsandprocesses. Inotherinstan ces,theexperience ismoreconventional, inthatlowercosts involveincreasesinweight;inthesecases,listsofweightin creasesversuscostdecreasesaremaintained, andthemost attractiveconceptsareincorporated uptotheacceptable weightlimitsoftheenginespecification. Copyright©SocietyofAutomotive Engineers,Inc.1973 Allrightsreserved. Downloaded from SAE International by University Of Newcastle, Wednesday, August 08, 20182 weight,operatingtemperatures, andcompression ratioswere allfoundtobeindicatorsofcost,butthemostsignificantcor relationtoenginecostwasobtainedwithanindexfactorof thecombinedmaterialandmachining/fabrication costsre quiredtomakeanengine.AsfirstproposedbyR.J.Mauer, oftheNavalAirSystemsCommand, thisMIFwasthesumma tionoftheproductofarelativematerialcostandthematerial inputweightforeachclassification ofmaterialusedinmaking agivenengine.Rawmaterialrequiredforthemanufacture of eng