Injection Moulding of Thermoplastic Polymers

  • M. Vincent
Part of the NATO ASI Series book series (NSSE, volume 302)


The injection moulding of thermoplastic materials can be divided into the following steps :
  • plastication in a screw-barrel system

  • filling of the cav ity : us u ally, the flow rate is imposed, w ith a constant value, or with successive steps with different flow rates. Sometimes a limit of the pressure is specifiied by the operator, so that the end of filling is at constant pressure

  • packing-holding : the pressure at the entrance of the cavity is now imposed, and an extra flow of material compensates the thermal shrinkage

  • cooling in the mould : this step begins when the gate is frozen, although, of course, the polymer is cooled as soon as it enters the cavity which is kept usually around the room temperature.

  • ejection

  • cooling outside the mould


Residual Stress Injection Molding Injection Moulding Filling Stage Flow Front 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media Dordrecht 1995

Authors and Affiliations

  • M. Vincent
    • 1
  1. 1.Centre de Mise en Forme des Matériaux, URA CNRS 1374Ecole des Mines de ParisSophia-Antipolis CedexFrance

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