某公司官方培訓手冊英文版

MSC.Marc

version

2005

TrainingMACHININGSheng

PingWangMSC.Marc

DevelopmentFEM

Simulation

of

NC

Machining

ProcessesObjectivesTo

predict

the

effects

of

insitu

residual

stressredistribution

due

to

complex

3Dmachiningof

bulk

components.To

streamline

process

design

so

as

tominimize

partfit-upissues.Bottomline

:

To

reduce manufacturing

cycletime

thereby

achieving

productivityimprovement

and

cost

savings.FEM

Simulation

of

NC

Machining

ProcessesApproachPseudo-simulation

ofmachiningprocessthroughautomated

material

removal

using

NC

cuttingfiles

(apt

or

cl

files)

asinput.AssumptionApriori

residual

stresses

in

depth

ofwork-pieceinfluence

resulting

distortions

more

than

surfaceresidual

stresses

introduced

by

cuttingprocess.Companies

that

have

been

using

ApproachBoeing,

UTC

(Sikorsky),

Embraer,

PicheneyProductSolver

-

MSC.Marc

2005GUI

-

MSC.Marc

Mentat

2005Material

Removal

SimulationMaterial

toberemovedMaterial

to

be

removedBeam

#1Material

Removal

Simulation

FlowchartFEModel(FEA

Input

Data)FEA

Results(Post-processing)NC/CAD

DATA(Cutter

Path-

apt,clfiles)Initial

StressCAD/CAMSystemFEA

Solver(MSC.Marc)Solution

ProcedureNC

Data

InterfaceInitial

Residual

Stress

InputFE

SolutionVisualizationNC

/

CAD

DataPPRINT************************************************************PPRINT

LOAD

2"

DIA

FACE

MILL

WITH

.312

CORNERRADIUSPPRINT************************************************************LOADTL/230002,LENGTH,0,OSETNO,1SPINDL/9963,CLWCOOLNT/FLOODRAPIDCUTTER/2.000000,

.312000,.688000,CUTTER/

2.0,.3120,.6880,.3120,.0,.0,4.0.312000,.000000,$FEDRAT/

50.0.000000,4.000000GOTO/

20.0,20.0,20.0TLAXIS/.000000,.000000,

1.000000PPRINT***************************************FEDRAT/50.0000*********************GOTO/20.00000,20.00000,20.00000PPRINT

LOAD

2"

DIA

FACE

MILL

WITH

.312

CORNERPT1RADIUSPPRINT************************************************************LOADTL/

230002.0,LENGTH,.0,OSETNO,1.0SPINDL/

9963.0,CLWCOOLNT/

FLOODRAPIDGOTO/

-2.0,19.0,20.0RAPIDGOTO/

-2.0,19.0,14.0FEDRAT/

150.0GOTOPTRAPID/2-2.00000,19.00000,20.00000GOTO/

-2.0,19.0,13.30GOTO/

.0,19.0,13.30FEDRAT/

105.0GOTO/-2.00000,19.00000,14.00000GOTO/

28.0,19.0,13.30PT3FEDRAT/

150.0FEDRAT/150.0000GOTO/

28.0,17.60,13.30GOTO

/PTGOTO

/4-2.00000,.00000,19.00000,19.00000,13.3000013.30000PT5APT

SourceDataCL

DataNC

Data

InterfaceCutter

Geometry

IdentificationCutter

statement:CUTTER/d,r,e,f,

,

,hdf

ehrDifferent

Cutter

ShapesNC

Data

InterfaceCutter

Path/Passes

IdentificationDetection

of

the

starting

pointandending

point

of

each

path/sub-passes.Calculation

of

cut

volume.Based

on

cutter

cross-section

and

cuttermotion.Cutter-Mesh

Intersection

DetectionDetection

ofelement-cutterintersection.Initial

Residual

StressInputMethods

availableinMSC.Marc:NumericalDataInput(Pre-State)TransferofstressesfromendofpreviousmanufacturingsimulationtometalremovalsimulationusingPRE-STATE.Accurate:Fromint.

point

to

int.point.

ofthesame

FE

mesh.User

friendly.Initial

Residual

StressInputPre-State:Initial

Residual

StressInputMethods

availableinMSC.Marc(cont.)Text

datafileTransferofmeasurementdata

(X-raydiffraction,etc.)tomodelviatextdata.ResidualStressdataintheworkpieceareautomaticallyextrapolatedtotheunderlyingmesh.Initial

Residual

StressInputText

datafileInitial

Residual

StressInputMethods

availableinMSC.Marc(cont.)Tabular

formatFESolutionTreatmentofIntersectedFinite

ElementEntitiesFullyIntersectedFiniteElementsAutomatically

deactivated

andStressesreleased.PartiallyIntersectedFinite

ElementsSubdivided

using

Local

Adaptive

Remeshing.User

setslevels

of

sub-divisiontobeused.Fullyintersectedchildelementsaredeactivated.FESolutionwith

ReducedNumber

ofElementsFESolutionAdaptiveRemeshingfor

MachiningFESolutionMachiningLoadcase

definitionAdaptiveMeshingExampleHole

DrillingInitial

FEMmodel:408brickelements,

668nodesFinalFEMmodel:Onelevelsplitting:600:528elementsTwolevelsplitting

:2328:1656elementsThreelevelsplitting:

8472:5112elementsNote:redreferstothe

activeelementsExample:Hole

DrillingWithout

remeshingWith

1levelremeshingAccuracyComparisonbaccutterExample:Hole

DrillingcWith

2levels

remeshing With

3levels

remeshingSignificantimprovementofaccuracywith

adaptive

remeshingcutterExample:PocketCuttingCutsintheLowerSurfa

ceCutsintheUpperSurfaceMore

CutsintheUpperSurfaceFirstpocketcut…Secondpocket

cutSpring-backafterReleasePocketCuttingFrameCuttingFrameCuttingSale

Points:Practicaltooltosimulatereal-world

machiningprocesses.CADgenerated

NC

files

areused

to

determinethecuttergeometry

andpath.Convenient

residual

stressimportmechanism

isprovided.AutomatedNCdatainte