Co-rotating twin-screw extruders are used in many branches of industry for producing, preparing, and processing highly viscous materials. They find a wide variety of applications, especially in the plastics, rubber, and food industries. Co-rotating twin-screw extruders usually have modular configurations, and are thus quite flexible for adapting to changing tasks and material properties.

This book provides basic engineering knowledge regarding twin-screw extruders, providing a foundation of knowledge about machinery, processes, and material behavior. It covers the most important technical requirements and provides examples based on actual practice. Better understanding of the process is emphasized, as this is a prerequisite for optimizing twin-screw designs and operating them efficiently.

From the Preface: “...The first twin-screw compoundder (ZSK) went into production at Werner & Pfleiderer in 1957, marking the beginning of a success story for this type of machine. The first major applications were in the chemical industry. Today, the machine is predominantly used in the plastics industry, e.g., in extrusion and compounding...”

Target Audience: Engineers and technicians in the compounding, extrusion, rubber, and food processing industries; also designers and marketers of twin-screw extrusion equipment.

Table of Contents:

Introduction

Historical Development of the Co-Rotating Twin Screw

Rheological Properties of Hot Melts

General Overview of the Compounding Process: Tasks, Selected Applications, and Process Zones

Geometry of the Co-Rotating Extruders: Conveying and Kneading Elements

Modeling: Possibilities and Limitations

Pressure Generation and Energy Input in the Melt

Computational Fluid Dynamics

Mixing and Dispersing: Principles

Degassing Polymer Melts with Co-Rotating Twin Screw Extruders

Simulation or Scale-Up — Alternatives for Extruder Layout?

Screw Elements for Co-Rotating, Closely Intermeshing, Twin-Screw Extruders

Overview of Patented Screw Elements

The ZSK Series and Applications in the Chemical Industry and for Renewable Raw Materials

ZSK-NT: The New Two-Stage Processing System for High Throughputs

Material Selection for Twin-Screw Extruder Components in Contact with Resin

Drive Units for Co-Rotating Twin-Screw Extruders

Index