Radial Profiling of Parison by the use of flex ring technology

W. Michaeli, J. Grüenewald and Th. Brüemmer

Institute of Plastics Processing (IKV) at RWTH Aachen University

Pontstraße 49, 52062 Aachen, Germany

1 Abstract

Blow molded molding parts like plastic fuel tanks or packaging articles in the food and consumer goods industry are becoming more and more complex in geometry because of their complex design. A trend towards small packaging is also increasingly observed. Particularly the wall thickness distribution of molding parts is essential for the quality of blown parts and the efficiency of the process. In most cases a preferably even wall thickness distribution for the produced blow molded part is essential, because areas with minor wall thickness represent mechanical weak spots. On the other hand the user-related optimization of wall thickness should help to reduce the wall thickness as much as possible, because material costs make up a high proportion of total costs (up to 85 % in the packaging sector). The aim for fabricators now is not only an even wall thickness distribution but also the wall thickness distribution appropriate to the stress while minimizing the amount of material use.