August 2007 Rapid Prototyping Consortium. Changing the way plastics parts and molds are analyzed and optimized

Transcription

1 August 2007 Rapid Prototyping Consortium Changing the way plastics parts and molds are analyzed and optimized Jonathan Toy Engineering Services Manager Moldflow Corporation

2 Cost of Change

3 Injection Molding Process Primary Problem - Islands of Automation Part Design Mold Design Production Islands of Automation adds cost and creates quality and process efficiency problems

4 OEM/Erie Problem: Cycle times were longer than expected. INDUSTRY: Automotive PRODUCT:Cowl Screen End Cap Solution: SAVINGS ACHIEVED MPI/3D, MPI/FLOW, AND MPI/COOL Analyses identified thick/chunky areas, then through optimization of the part design and cooling system design, cycle times were reduced by 53%! Annual savings of 25,000 US$ in cycle time reduction

5 Airmate Electrical Co.,Ltd Problem: unbalanced flow Great amount of warpage INDUSTRY: Household appliances PRODUCT: Box fan housing Solution & Benefits: Design changing of runner system Warpage reduced by 45% Cycle time reduced by 35% Clamping force reduced to 150 tons Solved difficult assembly problem, machine cost reduced by at least 50%!

6 Niko N.V. A coil should be mounted in a DIN rail housing. In older, similar products, a configuration with 4 little stakes and 3 springs is used for the fixture. For a new universal dimmer, the proven fixture geometry was copied, and a simulation seemed unnecessary. However, the nominal wall thickness of the base plate had changed. Mr. Patrick Meeus of Niko, performing Moldflow MPI simulations on every new plastic product, decided to do the simulation anyway. INDUSTRY: PRODUCT: Electric Switches Dimmer housing The MPI simulation showed that short shots would appear in the stakes and springs, due to the changes in the base plate. This was not expected. By optimizing wall thicknesses this problem was resolved before the mold was cut in steel. Lower mold cost - the mold was right from the start! Shorter time-to-market!

7 Moldflow Corporation [NASDAQ: MFLO] Founded 1978 Melbourne, Australia Acquired C-Mold 2000 Global Operations (Development, Sales, Support) Global Partners (Design, Research, Manufacturing, Hardware) Global Customers (8,000+ in 70 countries)

8 Trend Structural/Flow Simulation Vehicle Engine Radiator Water Tank Radiator Outlet Water Tank Air Courtesy: Valeo Inlet Water Tank

9 Trend Structural/Flow Simulation Internal pressure load case Stress level about 50% of the tensile strength Weld Line First failure Courtesy Valeo

10 Interfaces to Structural CAE Overview Historical method of analyzing plastic parts in Structural CAE: Generic & isotropic material data Stress-free initial state of plastic Original CAD geometry New method (using data from the MPI interface): Grade-specific & anisotropic material properties Process-induced material anisotropic data (for fiberfilled materials) Account for residual stresses Use post-molded deformed shape

11 3D Model Interface Details Data exported for a 3D mesh Unfilled Materials Elastic modulus, Shear modulus & Poisson s ratio from Material database Coefficient of thermal expansion (CTE) from Material database Elemental (for each 3D tetrahedral element) initial stress values Fiber-filled Materials Elemental Elastic modulus, Shear modulus & Poisson s ratio Elemental CTE Elemental equivalent pressures Elemental Fiber orientation angle

12 Trend Virtually Simulate Entire Assembly Droptest of entire phone Droptest simulation of the whole Phone in ABAQUS/Explicit Residual stresses and part deformations to be included in all parts of this model Courtesy Nokia

13 Trend Virtually Simulate Entire Assembly Integration Fiber orientation Shrinkage Flow Dynamic Stress Fully integrated analysis: σ vonmises =35.9 MPa Traditional stress analysis: σ vonmises =14.4 MPa Fully integrated analysis: σ vonmises =80.1 MPa Traditional stress analysis: σ vonmises =17.2 MPa Courtesy Nokia

14 Graco Children s Products Problem: Weld line anticipated to be in the top of the bridge area is is expected to cause the base to fail during crash testing. INDUSTRY: Children s Products PRODUCT: Car Seat Base Solution: The initial proposed solution was to add flow leaders to move the weld line off the top of the bridge area. Flow and stress analyses deemed the flow leaders unnecessary, saving a 7% part weight increase. Prototype parts performed well in crash testing! SAVINGS ACHIEVED WITH MPI/FLOW AND MPI/ANSYS INTERFACE Annual savings of 115,000 US$ in material alone See See also also imug05 presentation by by Tom Tom Lacey, Graco

15 Model / Mesh Types Midplane Fusion 3D

16 3D Flow Animation

17 Moldflow Product Families Moldflow Plastics Advisers Preliminary Design Analysis & Optimization System Directional Simulation Tool Targeted at Preliminary Part & Mold Design Part Adviser Mold Adviser Answers fundamental manufacturing questions Will the part fill? Where are weld lines and air traps? Which material? Where should gates be located? Wall Thickness?

18 Moldflow Product Families Moldflow Plastics Insight In-depth Analysis & Optimization System Definitive Simulation Tool Industry Best Breadth & Depth World s most popular in-depth injection molding simulation software

19 Solution Depth MPI/Flow Predicts the flow of plastic throughout the injection molding cycle to ensure quality parts and optimized process. Covers Insert-Molding and 2-Shot Molding. MPI/Cool Mold cooling analysis optimizes mold and cooling circuit design to achieve uniform component cooling within the minimum cycle time. MPI/Warp Predicts and controls the shrinkage and warpage of plastic parts, ensuring parts are fit for purpose.

20 Solution Depth MPI/Optim MPI/Optim allows you to perform an injection molding machine-specific analysis which takes into account the actual machine response time, maximum injection velocity, and the number of steps that can be programmed for velocity and pressure profiles on the machine controller. MPI/MuCell Microcellular (MuCell ) injection molding is a process in which a supercritical fluid (SCF) such as carbon dioxide (CO2) or nitrogen (N2) is mixed with molten polymer and injected into the mold to produce microcellular foam. MPI/Birefringence Birefringence is an optical defect that typically manifests as double images and is therefore undesirable in optical lens applications. 3D Birefringence analysis is an add-on option to 3D Warp to predict such occurrences.

21 Solution Depth MPI/Gas Optimization of the design and production of Gas Injection Molded (GIM) components. MPI/Co-Injection Predicts the injection molding of 2 thermoplastic polymers, and their distribution through the part thickness. MPI/Injection Compression Predicts the flow of plastic throughout the injection molding cycle and the effects of the compression process.

22 Solution Depth MPI/Reactive Molding Predicts the flow and cure of thermoset plastic to ensure quality parts and optimized process. MPI/Microchip Encapsulation Extends Reactive Molding to examine microchip encapsulation, wire sweep and paddle shift. MPI/Underfill Encapsulation Extends Reactive Molding to examine the underfill (flip-chip) encapsulation process.

23 Product Design

24 Geometry Import

25 Analysis Selection Wizard

26 Material Selection

27 Processing Conditions

28 Best Gate Location

29 Injection location

30 Analysis Selection Wizard

31 Plastic Flow Analysis

32 Results Summary

33 Confidence of Fill

34 Dynamic Adviser

35 Dynamic Adviser

36 Dynamic Adviser

37 Weld Lines and Air Traps

38 Help System

39 Results

40 The Problem

41 The Solution

42 Results

43 Multi Cavity Mold

44 Moldflow Communicator (MC) Results viewer Anyone can use it Share Moldflow results with colleagues around the world Supports MPI 6.1 MPA 8 Reads Moldflow results file FREE DOWNLOAD!

45