制造成本及影響-Influences-on-Manufacturing-Cost-V4

SCA-DTC01

DESIGNTOCOST

FACTORSINFLUENCINGCOST

SCA-DTC01|Designtocost

FactorsinfluencingManufacturingCost

Material

ManufacturingCost

Process

…otherfactors

Quantities

Design

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SCA-DTC01|Designtocost

FactorsinfluencingManufacturingCost

Internal

Stakeholders

Customer

RequirementSpecification

(Lastenheft)Whatisneeded?

Functional

Specification

(Pflichtenheft)

Whatshallbe

delivered

RoughConcept

Whatcanberealized

Law,ruleetc.

RequirementEngineering

-CrossfunctionalCollaboration

?Engineering

?ProjectPurchasing

?Manufacturing…

SCA-DTC01|Designtocost

Basic

Conditions

?ManufacturingProcess

?Material

?Weight

?Dimension

?Volume

…

Economic

Requirements

OrganizationalRequirements

BasicCategoriesofRequirements

Functional

Requirements

TechnologicalRequirements

?Task

?Power

?Environment

?Load/Distribution

?Lifetime

?Reliability

?Interface

?Service

…

SCA-DTC01|Designtocost

ImpactofEngineeringoncost

Productcostsin[%]

100

50

0

~5%

~7%

~22%

~18%

~38%

~70%

~28%

Costset

(established)

~3%

~9%

Costrealized(incurred)

Material

Productionplanning

Sales

Administration

costs,

Suppliers

Production

Design

Development

Developmentof“costset”and“costincurred”followan

opposingpattern.

Aftertheproductdesignis

completed,thereisonlysmallinfluenceoncost.

*Ehrlenspielet.al.p.15

Approx.70%ofproductcostaresetduringproductplanningandproductdevelopment

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SCA-DTC01|Designtocost

Averagemanufacturingcostreductionbyvalueanalysis*

VariableManufacturingcosts

before

value

analysis

100%

33%

Savings=

unneces-

sarycost

?1%other

?15%purchasing

?19%productionplanning

?65%designanddevelopment

Responsibilityforthe

unnecessarycost

after

value

analysis

67%

}Necessarycost??

*Ehrlenspielet.al.p.15

In135valueanalysisconductedin35companiestherewasanaveragecostreductionoff33%.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SCA-DTC01|Designtocost

Exampleforcostreduction

Example:

Rockerarm(Kipphebel)formediumspeeddieselengine(MTU)*

twoparts

onepart

1forgedpart16MnCr5

2forgedpartsCk15

Manufacturingcosts:100%

9productionsteps

Productiontime161min/pc.

Manufacturingcosts:67%

3productionsteps

Productiontime106min/pc.

Integraldesignoftherockerarmledtoacostreductionoff33%.

*Ehrlenspielet.al.p.14

Result:slightincreaseinmaterialcostbuthighdecreaseinproductiontimebecauseoflessproductionsteps.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SCA-DTC01|Designtocost

Waystoreducemanufacturingcost:Overview

Lessmaterial

MaterialCost

Other/lowercostmaterial

Part

ProductionCost

AssemblyCosts

Reduce

ManufacturingCost

Fewerproductionoperations

Lowercostproduction

processes,tools,machines

Fewerassemblyoperations

Lowercostassemblyprocesses

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SCA-DTC01|Designtocost

Tolerances

Requirements

Mainfactorsinfluencingmanufacturingcost

Concept

Surfacefinish

ManufacturingCost

(e.g.functionalprinciple,materialtype,complexity)

Productionand

assemblytechnology

Quantitiesproduced

Shapedetails

(influencedstronglybymaterial,quantitiesproducedandsize)

Size

(e.g.dimension,amountofmaterial)

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SCA-DTC01|Designtocost

Factorsinfluencingmanufacturingcost

costfactors

productionprocess

productionquantity

sizeand

dimension

loading(nominalstress)

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

Productionprocess

SCA-DTC01|Designtocost

ProductionProcess-designchangespool

MachinetoMachine

OnespindleABC

Invest:165.000ε

Machinehourrate:10,6ε/h

CycleTime:17s

CostSystem:5,00ε/100

Amoresimpledesign(here:nocrossmilling)leadsonthesamemachinestolesscycletimeandthereforetolowercosts.

MultispindleMS32G

Invest:1.000.000ε

Machinehourrate:55,86ε/h

CycleTime:3s

CostSystem:4,65ε/100

Designchange

-Nocrossmilling

Cycletimedrops

OnespindleABC

Invest:165.000ε

Machinehourrate:10,6ε/h

CycleTime:4s

CostSystem:1,18ε/100

MultispindlesMS32G

Invest:1.000.000ε

Machinehourrate:55,86ε/h

CycleTime:1,2s

CostSystem:1,86ε/100

-onespindle:17sto4s

-multispindles:3sto1,2s

Costdrop

-onespindle:5,00ε/100to1,18ε/100

-multispindles:4,65ε/100to1,86ε/100

Simpledesignlesscycletimelesscost

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

Productionprocess

SCA-DTC01|Designtocost

Processchange-fromturningtodeepdrawing

TechnologytoTechnology

72,3

11,6

0,2

0,3

OH*

Packing

Test

Wash

Turning

4,2

36,5

30s/pc

IndexG2001/3Operator

19,5

S235JR;2,0ε/Kg

Netweight25,1g

Grossweight125,3g

MAT

Processchange

-DeepDrawing

25,0

OH*

4,2

2,5

3,2

7,3

6,7

0,2

1,0

6h/7200Stk.

Ipsen

?Operator

Packing

Test

Wash

Glowing

DeepDrawing

MAT

10Hübe/minKaiser680-1?Operator

S235JR;2,0ε/Kg

Netweight25,1g

Grossweight39,3g

*OH-Overheads

Achangeinprocess/technologyfromturningtodeepdrawingleadstolowerprocesscost.

Materialcostarereducedbecauseoflessgrossweight(from125,3g/pcto39,3g/pc)

Costdropfrom72,3ε/100to25,0ε/100(-65%)

Processchangewithsamedesign=>lessprocesscost,lessmaterialcost

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

Productionprocess

SCA-DTC01|Designtocost

Stamping-Process

BlankingorFineBlanking?

Blanking

?Productionofsheetmetalworkpieceswithhighoutput

?Simple,relativelyfavorabletoolgeometry

?Sheetmetalsupto20mmthickness;midtolerance+/-0,1mm

FineBlanking

?Productionofhigh-precisionsheetmetalworkpieceswithflattenandfreefromcrackcuttingsurfaces

?Threesteppressprocess

?Smalltolerancesatcuttingsurfacesfeasible

?Sheetmetalupto16mmthickness;tolerances+/-0.025mm

Blanking

FineBlanking

Cutsurface

Cutsurface

Tearingedge

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SCA-DTC01|Designtocost

Stamping-Process:changein

loading:

Productionprocess

FineBlanking

Cost:680T/€

Blanking

Cost:585T/€

160KNPressingstrength

Cost/

100pc:

0,35ε

Machine

hourlyrate:

120

Strokes

per

minute

25,1ε/h

Becauseofhigher

x4,3

machinehourlyrate

andhighercycletime

Assumption:5760hp.a.

costoffineblankingaremuchhigher.

350

Strokes

Cost/

100pc:

0,08ε

per

minute

Machine

hourlyrate:

15,8ε/h

Costforfine-blankingaremorethan4timeshigherthennormalblanking!Whichtolerancesarereallyrequired?

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

Productionquantity

SCA-DTC01|Designtocost

Influenceofproductionquantityoncost

Costreductiondueto…

divisionofone-time

cost

e.g.setupcosts

Costreduction

throughincreasing

quantity

useofmoreefficientprocesses

optimizeddesign

trainingeffects

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SCA-DTC01

Influenceof

Productionquantity

|Designtocost

productionquantity

Costperpart(ε/piece)

Increasingquantitywillleadtolowercostperpartbecauseof

ldivisionoffixedcost

ltrainingeffects

loptimizeddesign

lreductionofsetuptimesperpiece

luseofmoreefficientprocesses

Quantity

Withincreasingquantitycostperpartwilldecrease.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

Productionquantity

SCA-DTC01|Designtocost

Useofmoreefficientprocesses

Costinε

FixedcostA

FixedcostB

crossoverquantity

ProcessA

ProcessB

Quantity

ProcessAhashigherfixedcostbutlowervariablecostthanprocessB.

WithlowquantitiesprocessAhaslowercost.

ThereisacrossoverquantityatwhichprocessBhaslesscost(andalsolesscost/pc)thanprocessA.

Increasingquantitywillleadtoprocesschanges.

Changeintheproductionprocesseswithincreasingquantities.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

Productionquantity

SCA-DTC01|Designtocost

Useofmoreefficientprocesses(casting)

Processeswithhighonetimecostoftenhavelow

processcost(variablecost)-andtheotherwayaround.

Thehigherthequantitythemoreefficientarethoseprocesses

Cone

Cp-time

CMAT

Cone:Productiononetimecost(set-up,tools,frames)

Cp-time:Productioncostperpartbecauseofprocesstime(machineuse)

CMAT:Materialcostperpart

ChangesintheproductionprocessesfromAtoCreducemanufacturingcostswithincreasingquantities.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

sizeand

dimension

SCA-DTC01|Designtocost

Influenceofsizeanddimension

MaterialCost

Materialcostsincreaseapproximatelyproportionaltothematerialvolume,thereforewiththethirdpowerofthelineardimension(forgeometricallysimilarcomponents).

ProductionCostforsetuptime

Ingeneralsetuptimesandthereforecostsincreasewiththesizeoftheworkpiece.

ProductionsCostforcycletime

Cycletimeincreaseswiththesize.

Forsomemachines(finishmachining,grinding)proportionallytothesurfacearea(secondpower)andforsomemachines(roughmachining)proportionallytothe

volume(thirdpower).

Biggersizeincreasesmaterialcost,setuptimeandcycletimeandthereforeleadstohighermanufacturingcost.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SCA-DTC01|Designtocost

Example:case-hardenedandgroundgears*

25

PCs~φL0,5

Productioncost

fromset-uptimes

20

~φL3

PCe~φL2

Productioncost

fromtotaltimes:

15

Proportionaltosurfacearea

~φL3

ManufacturingCost,MC

~φL2~φL

10

MtC~φL3

Materialcosts,weight-dependentcosts:

proportionaltovolume

5

0

0.25

0.16?50

12345

10802706401250?200?400?600?800?1000

φL=

Weight[kg]

Diameter,d[mm]

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

sizeand

dimension

Assumptions:

?Single-unitproduction

?10-14productionoperations

?sameproductionmethod

?samematerial

Increaseofthemanufacturingcostwithincreasingsize!

*Ehrlenspielet.al.p.163

Einsatzgeh?rteteundgeschliffeneZahnr?der

Relativevaluesofmanufacturingcost

d

sizeand

dimension

SCA-DTC01|Designtocost

Influenceofsizeanddimension

Costcurveslope:smallparts

Forsmallpartsmanufacturingcostsincreaseslowlyandlinear(proportionaltothelinearratioφL=d1/d0).

Setupcostsarerelativelyhigh(increasewithφL0,5),

Materialcostarerelativelylow.

Costcurveslope:mediumsizedparts

Formediumsizedproductsthecostincreasewith(square):φL2

Productioncostdominate.

Costcurveslope:largeparts

Forverylargepartsthecostincreasewith(cube):φL3(i.e.proportionaltothevolume).Materialcostsdominateandgrowproportionaltovolume.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

sizeand

dimension

SCA-DTC01|Designtocost

Influenceofsizeanddimension

Manufacturingcostperpart

Sizereductionwilllowermanufacturingcostaslongasitisnotcarriedouttotheextreme(e.g.lightweightdesignmightinsomecasesleadtohighercost).

Weight(kg),Diameter(mm)

Smallersizeandlessweightreduceingeneralmanufacturingcost.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

loading

(nominalstress)

SCA-DTC01|Designtocost

Influenceofloading/nominalstress

Loading(Auslegung)referstothenominalloadingofactivesurfacesofthepart.

Differentkindsofloading:

-Mechanicalloading(tensionorcompressionthroughenergytransferwithsolidbodies.Limits:breakage,deformation,wear….

-Thermalloading

Limits:burning,cracking,warping….

-Corrosiveloading

Limits:corrosivedamage.

-Flowloading

Limits:erosion,cavitation,abrasivewear.

Oversizedpartswithnospecificloadingaremoreexpensive.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

loading

(nominalstress)

SCA-DTC01|Designtocost

Influenceofloading/nominalstress

Throughhigherspecificloading,thesizeofaproductandthusitsmanufacturingcostcangenerallybelowered.

Thisisoftenpossiblebyusingstrongermaterialsorappropriatesurfacetreatments.

But:Thechangeinloadingshouldnotleadtoalowerreliability!

Higherspecificloadingreducesingeneralmanufacturingcost.

21CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

loading

(nominalstress)

SCA-DTC01|Designtocost

Requirements:loadingandquantity

Loading

High

High

High

High

Low

Low

Quantity

Sample

Low

High

Medium

Medium

High

SCA-DTC01|Designtocost

WaystoreduceMaterialCost

ReduceMaterialCost

ReduceCost

ReduceGrossVolume

Usesurfacetreatedmaterial

SmalldesignLightdesign

LeanDesign

ReduceWaste

Usecostefficientmaterial

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SmalldesignLightdesign

SCA-DTC01|Designtocost

Smalldesign,lightdesign

Parallelpaths

parallelarrangementsofactivesurfacesresultsinadivisionofpowerintoseveralpathsandthustoadecreaseinsize

Overloadlimits

ensurethatthewholedeviceneedsonlybedesignedforthenecessarythroughput(notoversized)

Rotationspeedincrease

forrotatingenergyconversionmachinesthisisameasureforreductioninsizeandweight

Highstrengthmaterial

Axialloading

striveforaxialloadinginsteadofbendingortorsionsothematerialisuniformlystressedthroughoutthevolume

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SmalldesignLightdesign

SCA-DTC01|Designtocost

Smallandlightdesign-example*

LowstrengthboltHighstrengthbolt

Influenceoftheboltstrengthonweightandmaterialcost

Higherboltstrengthreducestheweightofthecomponentandthematerialcost.

Sockedheadbolts(DIN912)areespeciallyadvantageous

*Ehrlenspielet.al.p.181

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

Leandesign

SCA-DTC01|Designtocost

Leandesign–example*

0,77kg0,41kg

(weightreduction≈50%)

MachinedoutofaforgedpieceDeepdrawedpiece

Exampleofacontainershowsthechangeinprocessesfrommachiningaforgedpiecetodeepdrawing.

Resultsweresavingsofabout50%ofweightaswellasmanufacturingcost.

Thewallthicknesswasreducedfrom5mmto2mm.

*Ehrlenspielet.al.p.182

Changeinproductiontechnologymightsavecost.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

Leandesign

SCA-DTC01|Designtocost

Leandesign–example*

2ndredesign

1stredesign

casting

1part

100%weight

100%cost

4parts

60%weight

100%cost

2parts

60%weight

50%cost

*Ehrlenspielet.al.p.242

Changeindesignsavescost.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

ReduceWaste

SCA-DTC01|Designtocost

Reduceweightandwaste

Chosenear-netshapeproductionprocesses(e.g.casting,forging,sintering,sheetmetaldesign)

Castingsshouldbemademoreexact

Donotmachinepartsoutofasolidpiecebutuseforgedorcastsemifinishedparts

Withstampedpartspayattentiontotheuseofthesheets

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

ReduceWaste

SCA-DTC01|Designtocost

Reduceweightandwaste

△△△

Costreductionbymaterialsavings:

?Lowrack-andframegaps

?Profitablegeometricarrangement

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

ReduceWaste

SCA-DTC01|Designtocost

MaterialsavingsforexampleflangeHDP

Stampingoffinishedflange

Highcutoff

Materialwaste

About70%waste

Stampingof

separateparts

About45%waste

weldseam

Higheryieldbysplittinguptheflangeinto2parts

Bettergeometricarrangementbutjoiningofpartsnecessary

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

ReduceWaste

SCA-DTC01|Designtocost

Example:reducewastethroughremodeling

Remodelingmightsavecostbecauseoflesswaste.

CP/ASC|21.03.2018

?RobertBoschGmbH2016.Allrightsreserved,alsoregardinganydisposal,exploitation,reproduction,editing,distribution,aswellasintheeventofapplicationsforindustrialpropertyrights.

SCA-DTC01|Designtocost

Mate