PTC CREO MOLD ANALYSIS EXTENSION

PTC CREO MOLDANALYSIS EXTENSIONRobin Wei (robinwei@moldex3d.com)Russell J.H. Hsu (ruhsu@ptc.com)September 2014

TABLE OF CONTENTS Injection Molding Processes Introduction to Creo Mold Analysis Case Study Moldex3D Product Portfolio Appendix A Appendix B2

INJECTION MOLDING PROCESSES3

INJECTION MOLDING PROCESSESFillingPackingCoolingWarpPTC Creo Mold Analysis (CMA) is an injection moldingsimulation application that focuses on filling process4

INJECTION MOLDING PROCESSES1.Hesitation2.Race track phenomenon3.Air-trap4.Flow mark5.Unbalanced flow patternThe melt passes throughdifferent thickness areasThe 2 different gating scenario5

INTRODUCTION TO CREO MOLD ANALYSIS6

CMA OVERVIEW Process Wide Mold Filling Simulation – Creo Mold AnalysisMODELINGDesign partSIMULATEPerform asimulation withCMACheckResultMODIFYModify thegeometry orprocess condition7

USER INTERFACEPre-ProcessAnalysis ResultView & Report Tool8

CMA WORK FLOW Startup CMA Assign material Gate setup Analysis setup Run analysis Review result advisor Check analysis results Create report Save and retrieve data9

STARTUP CMARun CreoOpen a *prt file10

STARTUP CMALaunch Creo Mold AnalysisClick “Cold Analysis”The “Mold Analysis” tab will come out11

ASSIGN MATERIALChoose Material (Ex: ABS, ASAHI, STYLACVA29)12

GATE SETUP1. Select “Gate Setup” 2. Select ”Add” and then click amelt entrance position13

GATE SETUP (CONT’D)3. Enter the gate diameter4. Users can add new gate,edit and delete existinggate14

ANALYSIS SETUPSelect “Analysis setup” to set the process condition and mesh levelFilling time (sec.)Filling time here is defined as the time required to fullyfill the cavity with “incompressible” material. Based oncavity volume (part volume cold runner volume) andfilling time, a given volumetric flow rate is forwarded toMoldex3D Flow solver.Melt Temperature ( )Melt temperature is the temperature of the plastic meltat the melt inlet of the model.Mold Temperature ( )Mold temperature is applied to the temperatureboundary condition between mold base and part. CMAassumes that the boundary temperature distribution isuniform.15

ANALYSIS SETUPSelect “Analysis setup” to set the process condition and mesh levelIf users calculate the max cooling timeand sink mark, the packing analysiswould be added into analysis process.16

ANALYSIS SETUPSelect “Analysis setup” to set the process condition and mesh levelMove slider can select from “Coarse” to “Fine” fordifferent mesh levels. The lower level means the fewer elements, whichspeeds up the computation. The higher level means the more elements, whichcontributes to more accurate computation result.17

RUN ANALYSISWhen all settings are done.Click “Run Analysis” will launch analysis.18

REVIEW RESULT ADVISORClick “Select Analysis” and choose the runMelt front time is the default frame19

REVIEW RESULT ADVISORClick “Results Advisor” to find the problem the model may have.Air trapAir traps found inside the cavity.This may cause voids or surface defect.DegradationShort shotThe resultant melt temperature is more than themaximum working temperature of the material.HesitationThe flow speed is too low in some regions in thecavity causing flow hesitation. In extreme cases,flow hesitation may lead to hesitation mark on themodel surface or even short shot.Unbalanced gate contributionThe melt contribution for each gate is unbalanced.Weld lineSharp welding angles found at some places. Weldlines may become visible.Short shotModel is incompletely filled at the end of filling.Short shot may occur.20

REVIEW RESULT ADVISORClick “Results Advisor” to find the problem the model may have.Short shotClick the issues, the screen willshow the corresponding result21

CHECK ANALYSIS RESULTSThe screen can show the analysis result and x-y plot at the same time22

CHECK ANALYSIS RESULTS - VIEW CONTROLChoose the analysis result and click “View Control”Clipping FunctionParametersTo clip the present model to view result inside. To define a clipping plane by entering theSlicingequation of the planeShow single/multiple slicing plane.23

CHECK ANALYSIS RESULTS - VIEW CONTROLChoose the analysis result and click “View Control”ParametersIsosurfaceDefine the value to displayShow Isosurface on the model. Thevalues of every point on the isosurfaceare the same.24

CHECK ANALYSIS RESULTS - VIEW CONTROLChoose the analysis result and click “View Control”Switch the Tab to “Legend” to changethe display limit of the legend bar25

CREATE REPORTClick ”Generate Report” to generate power point report26

SAVE AND RETRIEVE DATA Click “Save Project” to save CMA data as *.xedz file. To check the previously analyzed result, click “ RetrieveProject” and load the *.xedz file that keeps the CMA data.27

CASE STUDY- CELL PHONE HOUSING28

CASE STUDY - CELL PHONE HOUSINGProduct Information Dimension––––Length: 127 mmWidth: 50 mmHeight: 5 mmAverage Thickness: 0.7 mm Materials– PP \ Advanced Composites \ ATX-880N-1 Processing Conditions– Filling time: 0.54 Sec– Melt temperature: 210 C– Mold temperature: 50 C29

ORIGINAL DESIGN – TWO GATESOriginal Design – Two Gates located on the ends of the product Potential Problems––––Air TrapDegradationUnbalanced flowWelding lineGates30

POTENTIAL PROBLEMSWelding Line Length/Thickness Ratio– The maximum L/T ratio reaches to 153.54The welding lines are aligned, forming a longweak line on the center31

POTENTIAL PROBLEMSSprue pressure Unbalanced flow– There is a 13% difference between the contributions of each gateThe maximum sprue pressure reaches to76.78 MPa32

REVISED DESIGN – THREE GATESGates33

IMPROVEMENTS – LENGTH/THICKNESS RATIO Length/Thickness Ratio– The maximum L/T ratio has been reduced from153.54 to 63.487Original designRevised design34

IMPROVEMENTS – UNBALANCED FLOW Unbalanced flow– The gate contributions are even in the revised designOriginal designRevised design35

IMPROVEMENTS – SPRUE PRESSURE Sprue pressure– The maximum sprue pressure decreased by 29 MP in revised design36

IMPROVEMENTS – WELD LINE Weld Line– The number and length of weld lines decreased– The weld line aren’t alignedOriginal designRevised design37

MOLDEX3D PRODUCT PORTFOLIO38

MOLDEX3D PRODUCT STRUCTUREStructure and Market PositioneDesignSYNCCreoeDesignCMACreoeDesign Basic39

Tooling ValidationClamping forceMulti-Cavity flow balanceRunner balanceInjection pressurePacking pressureOptimized PartDesignsProductivityDesign Verificationand PLM IntegrationProduct Life Cycle EfficiencyHPC / Remote ComputingCooling time reductionAccuracySensor and measurementPowerful post-processingtoolsQualitySophisticate processWarpage predictionMulti-Component MoldingIdentify flow balanceFiber OrientationIdentify residual stressValve gate controlMaterial degradationAdvanced hot runnerShrinkage predictionConformal cooling

01020304FlowPackCoolWarpEverything startsfrom filling analysisShrinkage compensation,minimize warpage effectEfficient moldtemperaturemanagementMinimize partdeformationfor design accuracyMCMFiberPrecise multicomponentmolding analysisPredict fiber length and orientation toobtain optimal designs and processconditionsHigh Performance Computing(HPC)Enable parallel computing and clusterspeed up the analysis process

IndicatorsAPPENDIX - A42

INDICATORSIndicators provide information and suggestions to optimize the analysis results:-Automatic Gate Creation (Gate Location Indicator)-Cooling Time Indicator-L/t IndicatorDetail instruction will be shown in the following pages.43

AUTOMATIC GATE CREATION Number of gates – The gate countsGate Direction – mold open direction ( /- X,Y,Z)Gate diameter – The diameter of gates (All the gates are the same)Click “Calculate” will calculate proper gates location.After calculation click “Apply” can add gate automatically44

L/T INDICATOR Flow Length / Thickness RatioLegend Range Setting – slider can change Min. and Max. scale bar45

COOLING TIME INDICATOR Legend Range Setting – slider can change Min. and Max. scale bar Material Information – info of material––––––Density (g/cm 3)Melt Temperature ( )Mold Temperature ( )Eject Temperature ( )Heat Capacity (erg/g.K)Thermal Conductivity (erg/sec.cm.K)46

APPENDIX – BRESULT INTERPRETATIONS47

MELT FRONT TIME Melt front is a position indicator as melt front boundary movement in different time duration inthe filling process. From the melt front advancement one can:––––––Examine the filling pattern of the moldingCheck potential incomplete filling (short shot) problemIdentify weld line locationsIdentify air trap locationsCheck gate contribution for runner balanceCheck proper gate location to balance flow and eliminate weldline.48

AIR TRAP & WELD LINE Air Trap result shows the possible locations that air trap could have occurred. Weld Line result shows the weld lines that indicate potential spots of weaker structure. Thedarker the weld line, the weaker the structure.49

SINK MARK INDICATOR Sink Mark Indicator is the index to evaluate the packing effect. Positive value indicates that the packing is not enough, which it may lead to sink mark. Negativevalue indicates over-packing. An optimized packing result will have sink mark indicator close to zero.50

MOLDABILITY Moldability result shows the ease of fill.51

PRESSURE Pressure distribution of the cavity is shown in different colors at current instant. Based on thepressure drop and distribution, users can revise the part and mold design. From the pressure distribution one can:–––––Check the pressure transmission situationCheck runner system pressure dropCheck flow balance of the designAvoid overpacking and flashing of meltExamine the extent of packing/holding.52

TEMPERATURE Plastic melt temperature distribution at current instant. For 3D calculation, the temperature distribution expresses temperatures in all threedimensional for the entire cavity.53

CENTER TEMPERATURE Center temperature result shows the center melt temperature in the thickness direction atcurrent time step. The center temperature is calculated by interpolating from the temperature values of the nodesthat forms the element at the center of the path along the thickness direction.54

BULK TEMPERATURE Bulk temperature is the velocity-weighted average melt temperature in the thickness directionat current time step. In general, bulk temperature distribution can reflect the trend of flow path and therefore theactual path of pressure transmission.55

MAX. SHEAR STRESS This result shows the recorded peak value of shear stress of each element during the filling stage. Note that the maximum shearstress values shown in this result are not necessarily in the same time step. You can use this result to determine if the maximum shear stress in the finished part will exceed the maximum allowed shear stress.56

MAX. SHEAR RATE This result shows the recorded peak value of shear rate of each element during the filling stage. Note that the maximum shear ratevalues shown in this result are not necessarily in the same time step. Shear rate is the rate of shear deformation of the material during the polymer processing. Shear rate distribution is related to thevariation of velocity gradient and molecular orientation. High shear rate tends to drastically deform molecular chains even to breakand then weaken the strength of product. Viscous heating due to high shear rate also should be noticed.57

FROZEN LAYER RATIO Frozen Layer Ratio result shows the volume percentage of frozen plastic with respect to part thickness at current time step. Thisvalue will reach 100% as time passes by. The picture and the equation below explain how frozen layer ratio is calculated. Whereis the thickness of the upper frozen layer, is thethickness of the lower frozen layer, andis the thickness of the cavity.58