The objective of this paper is to present a methodology for automatically balancing multi-cavity injection molds with the aid of flow simulation. After the runner and cavity layout has been designed, the methodology adjusts runner and gate sizes iteratively based on the outputs of flow analysis. This methodology also ensures that the runner sizes in the final design are machinable. To illustrate this methodology, two examples are used wherein a 20-cavity mold and a 3-cavity mold are modeled and filling of all the cavities at the same time in both cases is achieved. In the case of the 20-cavity mold, the effect of changes in the processing conditions on the balance of the flow is also studied using a 33-factorial test. The examples indicate that the described methodology can be used effectively to balance runner systems for multi-cavity molds.

1.
Advanced CAE Technology, 1992, “C-Mold Reference Manual,” p. 114.
2.
Irani, R. K., Kim, B. H., and Dixon, J. P., 1989a, “Automated Injection Mold Gating System,” SPE 47th Antec, NY, May 1–4, pp. 1265–1267.
3.
Irani, R. K., Kim, B. H., and Dixon, J. P., 1989b, “Integrating CAE, Features and Iterative Redesign to Automate the Design of Injection Molds,” Proceedings, ASME Computers in Engineering Conference, Anaheim, July 30–August 2, pp. 27–33.
4.
Irani, R. K., Kim, B. H., and Dixon, J. P., 1990, “Automated Design of the Feed System of Injection Molds,” Manufacturing International ’90, Atlanta, GA, March 25–28.
5.
Jong, W. R., and Wang, K. K., 1990, “Automatic and Optimal Design of Runner Systems in Injection Molding Based on Flow Simulation,” ANTEC ’90, pp. 385–389.
6.
Douglas, M. C., 1984, Design and Analysis of Experiments, Second edition, John Wiley & Sons, pp. 284–292.
7.
Pye, R. G. W., 1989, Injection Mould Design, Fourth edition, Longman Scientific & Technical, copublished in the United States with John Wiley & Sons Inc., New York, pp. 140, 41, 149.
8.
Wang, V. W., Wang, K. K., and Hieber, C. A., 1983, “An Interactive Computer Program for Runner-System Design in Injection Molding,” SPE Tech Papers (ANTEC), pp. 663–665.
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