MSC Marcversion2005TrainingMACHININGShengPingWangMSC MarcDevelopment FEMSimulationofNCMachiningProcesses ObjectivesTopredicttheeffectsofinsituresidualstressredistributionduetocomplex3Dmachiningofbulkcomponents Tostreamlineprocessdesignsoastominimizepartfit upissues Bottomline Toreducemanufacturingcycletimetherebyachievingproductivityimprovementandcostsavings FEMSimulationofNCMachiningProcesses ApproachPseudo simulationofmachiningprocessthroughautomatedmaterialremovalusingNCcuttingfiles aptorclfiles asinput AssumptionAprioriresidualstressesindepthofwork pieceinfluenceresultingdistortionsmorethansurfaceresidualstressesintroducedbycuttingprocess CompaniesthathavebeenusingApproachBoeing UTC Sikorsky Embraer PicheneyProductSolver MSC Marc2005GUI MSC MarcMentat2005 MaterialRemovalSimulation Materialtoberemoved Materialtoberemoved Beam 1 MaterialRemovalSimulationFlowchart FEModel FEAInputData FEAResults Post processing NC CADDATA CutterPath apt clfiles InitialStress CAD CAMSystem FEASolver MSC Marc SolutionProcedure NCDataInterfaceInitialResidualStressInputFESolutionVisualization NC CADData CUTTER 2 000000 312000 688000 312000 000000 000000 4 000000TLAXIS 000000 000000 1 000000FEDRAT 50 0000GOTO 20 00000 20 00000 20 00000PT1PPRINT PPRINTLOAD2 DIAFACEMILLWITH 312CORNERRADIUSPPRINT LOADTL 230002 LENGTH 0 OSETNO 1SPINDL 9963 CLWCOOLNT FLOODRAPIDGOTO 2 00000 19 00000 20 00000PT2RAPIDGOTO 2 00000 19 00000 14 00000PT3FEDRAT 150 0000GOTO 2 00000 19 00000 13 30000PT4GOTO 00000 19 00000 13 30000PT5 CUTTER 2 0 3120 6880 3120 0 0 4 0FEDRAT 50 0GOTO 20 0 20 0 20 0PPRINT PPRINTLOAD2 DIAFACEMILLWITH 312CORNERRADIUSPPRINT 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 0GOTO 2 0 19 0 13 30GOTO 0 19 0 13 30FEDRAT 105 0GOTO 28 0 19 0 13 30FEDRAT 150 0GOTO 28 0 17 60 13 30 APTSourceData CLData NCDataInterface CutterGeometryIdentificationCutterstatement CUTTER d r e f a b h d f e h a b r DifferentCutterShapes NCDataInterface CutterPath PassesIdentificationDetectionofthestartingpointandendingpointofeachpath sub passes Calculationofcutvolume Basedoncuttercross sectionandcuttermotion Cutter MeshIntersectionDetectionDetectionofelement cutterintersection InitialResidualStressInput MethodsavailableinMSC Marc NumericalDataInput Pre State TransferofstressesfromendofpreviousmanufacturingsimulationtometalremovalsimulationusingPRE STATE Accurate Fromint pointtoint point ofthesameFEmesh Userfriendly InitialResidualStressInput Pre State InitialResidualStressInput MethodsavailableinMSC Marc cont TextdatafileTransferofmeasurementdata X raydiffraction etc tomodelviatextdata ResidualStressdataintheworkpieceareautomaticallyextrapolatedtotheunderlyingmesh InitialResidualStressInput Textdatafile InitialResidualStressInput MethodsavailableinMSC Marc cont Tabularformat FESolution TreatmentofIntersectedFiniteElementEntitiesFullyIntersectedFiniteElementsAutomaticallydeactivatedandStressesreleased PartiallyIntersectedFiniteElementsSubdividedusingLocalAdaptiveRemeshing Usersetslevelsofsub divisiontobeused Fullyintersectedchildelementsaredeactivated FESolutionwithReducedNumberofElements FESolution AdaptiveRemeshingforMachining FESolution MachiningLoadcasedefinition AdaptiveMeshingExample HoleDrillingInitialFEMmodel 408brickelements 668nodesFinalFEMmodel Onelevelsplitting 600 528elementsTwolevelsplitting 2328 1656elementsThreelevelsplitting 8472 5112elementsNote redreferstotheactiveelements Example HoleDrilling AccuracyComparison Withoutremeshing With1levelremeshing a b c cutter Example HoleDrilling With2levelsremeshing With3levelsremeshing c Significantimprovementofaccuracywithadaptiveremeshing cutter Example PocketCuttingCutsintheLowerSurface CutsintheUpperSurface MoreCutsintheUpperSurface Firstpocketcut Secondpocketcut Spring backafterRelease PocketCutting FrameCutting FrameCutting SalePoints Practicaltooltosimulatereal worldmachiningprocesses CADgeneratedNCfilesareusedtodeterminethecuttergeometryandpath Convenientresidualstressimportmechanismisprovided AutomatedNCdatainterfaceisprovidedtodetermineelement cutterintersection Localadaptiveremeshingisusedtoimprovefidelityofcutpart Thistoolcanbereadilyusedtosimulatecomplexreal worldmachiningproblemsandprovidedataonresultingstressdistributionsanddistortions