THE EFFECT OF THE PROCESSING PARAMETERS ON FROZEN LAYER FORMATION IN INJECTION MOLDING


Uluer O.

JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, vol.23, no.1, pp.249-255, 2008 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 23 Issue: 1
  • Publication Date: 2008
  • Title of Journal : JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY
  • Page Numbers: pp.249-255

Abstract

In the production of the plastic parts by the injection molding method, the molten hot plastic loses the heat when it touches to the cold mold wall and freezes. The frozen layer thickness has a very significant effect on the flow resistance. At the same time, the viscosity of the molten plastic exponentially increases with decreasing temperature. As a result of the decreasing of the molten plastic flow through the narrow mold gap, the whole of the mold cavity can not be filled or the consumption of the energy increases. The thickness of the flow layer is also reduced as the thickness of the frozen layer increases. In this study, during the molding of the L. D. PE (Low density Polyethylene) material, the effect of the injection velocity, the melt temperature and the mold wall temperature on frozen layer formation is numerically analysed using finite element method. In the analysis the Moldflow software is used. It is determined that increasing of the injection velocity, melt temperature and mold wall temperature cause the decreasing of the frozen layer.