Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-27T21:40:27.675Z Has data issue: false hasContentIssue false

A model of the injection moulding process

Published online by Cambridge University Press:  17 February 2009

N. Fowkes
Affiliation:
Department of Mathematics, University of Western Australia, Nedlands WA 6009, Australia.
G. Hocking
Affiliation:
School of Mathematical and Physical Sciences, Murdoch University, Murdoch WA 6150, Australia.
D. Hill
Affiliation:
Department of Mathematics, University of Western Australia, Nedlands WA 6009, Australia.
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

This paper is concerned with the injection moulding process, in which hot molten plastic is injected under high pressure into a thin cold mould. Assuming that the velocity and temperature profiles across the mould maintain their shape, a simple steady state model to describe the behaviour of a Newtonian fluid during the filling stage is developed. Various phenomena of the process are examined, including the formation of a layer of solid plastic along the walls of the mould, and the relationship between the flux of liquid plastic through the mould and the average pressure gradient along the mould. In any given situation, it is shown that there is a range of pressures and injection temperatures which will give satisfactory results.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1995

References

[1]Austin, C. and Miller, A., “Problem 6. Two phasė flow through a plastic mould”, in Proc. of the 1986 Math, in Industry Study Group (ed. de Hoog, F.), CSIRO Division of Mathematics and Statistics, (1987).Google Scholar
[2]Chen, B. S. and Liu, W. H., “Numerical simulation and experimental investigation of injection mold filling with melt solidification”, Polymer Eng. and Sci. 29 (1989) 10391050.CrossRefGoogle Scholar
[3]Couniot, A. and Crochet, M. J., “Finite elements for the numerical simulation of injection molding”, Proc. 2nd Int. Conf. on Numer. Methods in Industrial Forming Processes (Balkema, A. A., 1986) 165170.Google Scholar
[4]Elliot, C. M. and Ockendon, J. R., Weak and variational methods for moving boundary problems (Pitman, 1982).Google Scholar
[5]Flaman, A. A., de Groot, R. and Veltman, B., “Injection moulding experiments; a challenge to numerical simulation programmes”, Plastics and rubber processing and appl. 10 (1988) 155163.Google Scholar
[6]Kuo, Y. and Kamal, M., “Flow of thermoplastics in the filling and packing stages of injection moulding”, in Science and Technology of polymer processing: Proc. Int. Conf. on Polymer Processing held at MIT August 1977 (eds Suh, N. and Sung, N.), (MIT Press, 1979).Google Scholar
[7]Laskowski, L. and Stokes, N., “Problem 7. Warping of moulded plastics”, in Proc. 1986 Mathematics in Industry Study Group (ed. de Hoog, F.), CSIRO Division of Mathematics and Statistics, (1987).Google Scholar
[8]Ockendon, H., “Channel flow with temperature dependent viscosity and internal viscous dissipation”, J. Fluid. Mech. 93 (1979) 737746.CrossRefGoogle Scholar
[9]Pearson, J., “Variable viscosity flows in a channel with high heat generation”, J. Fluid. Mech. 83 (1977) 191206.CrossRefGoogle Scholar
[10]Rosenhead, L., Laminar boundary layers (Clarendon Press, 1963).Google Scholar
[11]Rubin, I.I, Handbook of plastic materials and technology (Wiley, 1990).Google Scholar
[12]Tayler, A., Mathematical models in applied mechanics (Clarendon Press, 1986).Google Scholar
[13]Wang, K. et al. , “Cornell injection moulding project”, in Science and Technology of polymer processing: Proc. Int. Conf. on Polymer Processing held at MIT August 1977 (eds Suh, N. and Sung, N.), (MIT Press, 1979).Google Scholar
[14]Wang, K. K., “Computer-aided engineering for injection moulding of plastics”, Amer. Inst. of Chem. Eng. Workshop. 84 (AIChE, New York, 1988) 3751.Google Scholar
[15]Yarwood, T. M. and Francis, T. G., Engineering and physical tables (Macmillan, 1963).Google Scholar