Multiple material moulds - Directives for blow moulding design

Conventionally, stretch blow moulds for bottles are designed as three moulding blocks. The first moulding block is the bottom of the bottle with integrated cooling. The other moulding blocks are the outside shape of the part, mostly related to the design aspect of the bottle and limited cooling. Where it concerns optimizing the cycle time and the related quality of blow moulded products, it is essential to modify the mould design, manufacturing and final applied mould materials. The thermal characteristics of several conventional, high-tech and rapid tooling mould materials have been analysed. These results are implemented in the final mould design strategy for blow moulding, having in mind the effect on the final cooling time and related part quality. To achieve optimal integration of mould design issues such as conformal cooling and mould material selection, a modular and fast exchange design principle for blow moulding of hybrid moulds is developed at University College Ghent. Originally designed for use within hybrid moulds, the modular and fast exchange mould can be used with any type of blow mould insert