Warpage Analysis of Injection Molded Parts Using Solid Model

This paper on "Warpage Analysis of Injection Molded Parts Using Solid Model" was presented at the NAFEMS World Congress on The Evolution of Product Simulation From Established Methods to Virtual Testing & Prototyping - 24-28 April 2001, The Grand Hotel, Lake Como, Italy.

Abstract

The requirement to create a shell model for warpage analysis on the midplane of the injection molded plastic part is at odds with the trend toward solid modeling. A flow analysis technique called Dual Domain Finite Element Analysis (DD/FEA) was introduced recently [1], which enables filling and packing analysis without the midplane model. In this paper a structural analysis technique using shell elements for thin-walled structures is developed in which only the surface mesh on the exterior of the part is used. The new technique is particularly suited to warpage analysis of injection molded parts without the midplane model. It ensures that the user can utilize the full suite of plastics CAE simulation (i.e. filling, packing, cooling and warpage) directly using the solid model generated by CAD systems. Results obtained with the new technique are presented and compared to those obtained on a midplane model.