The screw is the heart of an extruder and an injection molding machine. No other component in plastics processing has such a significant influence on the quality of the end product and the cost-effectiveness of the process. In recent years, it has been recognized that the „universal screws“ developed in the past no longer meet today's requirements in many cases. Insufficient melt qualities, low melt throughputs or low machine efficiencies are forcing the plastics are forcing the plastics industry to break new ground. The trend is moving towards „individual solutions“, tailored to the material, the process and the product.

However, the complexity of the actual plasticizing process and the growing number of innovative screw and system concepts make it difficult to deal with this topic. To this day, decisions are often made on the basis of experience and experimental investigations. The REX/PSI simulation package was developed as an alternative to the often used „trial and error“ method and presents a tool for optimization of extruders (REX) and injection moulding plasticizing units (PSI).

The software, which can be run on a standard PC workstation, can be used to simulate and evaluate the process. In addition, various program features support the systematic optimization of individual geometries and the design of entire machine series.

The simulation programs have been continuously developed since 1989 as part of a joint research project. By deriving more precise calculation models based on the three-dimensional finite element method and by implementing current screw geometries, the software is constantly being adapted to the growing needs of users. The programs thereby make a comprehensive contribution to the assessment and optimization of single-screw machines in industrial applications.

This user manual explains how to use the software. The theoretical approaches on which the calculations are based are presented in a large number of publications and dissertations. A list of relevant literature can be found in the appendix.

We would like to take this opportunity to thank all project participants once again, who made the development of this simulation software possible through their participation in the joint project.

Software Engineering Team REX/PSI (Email: software@ktp.upb.de) Paderborn