Extrusion Dies for Plastics and Rubber Design and Engineering Computations

• Main Author: Michaeli, Walter
• Format: eBook
• Language: English
• Published: München Hanser 2013
• Edition: 1
• Subjects: Plastics-Extrusion

Table of Contents:

• Intro -- Preface to the Third Edition -- Preface to the Second Edition -- Preface to the First Edition -- Contents -- 1 Introduction -- 2 Properties of Polymeric Melts -- 2.1 Rheological Behavior -- 2.1.1 Viscous Properties of Melts -- 2.1.2 Determination of Viscous Flow Behavior -- 2.1.3 Viscoelastic Properties of Melts -- 2.2 Thermodynamic Behavior -- 2.2.1 Density -- 2.2.2 Thermal Conductivity -- 2.2.3 Specific Heat Capacity -- 2.2.4 Thermal Diffusivity -- 2.2.5 Specific Enthalpy -- 3 Fundamental Equations for Simple Flows -- 3.1 Flow through a Pipe -- 3.2 Flow through a Slit -- 3.3 Flow through an Annular Gap -- 3.4 Summary of Simple Equations for Dies -- 3.5 Phenomenon of Wall Slip -- 3.5.1 Model Considering the Wall Slip -- 3.5.2 Instability in the Flow Function - Melt Fracture -- 4 Computations of Velocity and Temperature Distributions in Extrusion Dies -- 4.1 Conservation Equations -- 4.1.1 Continuity Equation -- 4.1.2 Momentum Equations -- 4.1.3 Energy Equation -- 4.2 Restrictive Assumptions and Boundary Conditions -- 4.3 Analytical Formulas for the Solution of Conservation Equations -- 4.4 Numerical Solution of Conservation Equations -- 4.4.1 Finite Difference Method (FDM) -- 4.4.2 Finite Element Method (FEM) -- 4.4.3 Comparison of FDM and FEM -- 4.4.4 Examples of Computations Using the Finite Difference Method -- 4.4.5 Examples of Computations Using the Finite Element Method -- 4.5 Considerations of the Viscoelastic Behavior of the Material -- 4.6 Computation of the Extrudate Swelling -- 4.7 Methods for Designing and Optimizing Extrusion Dies -- 4.7.1 Industrial Practice for the Design of Extrusion Dies -- 4.7.2 Optimization Parameters -- 4.7.3 Optimization Methods -- 4.7.4 Practical Applications of Optimizations Strategies for the Design of Extrusion Dies -- 5 Monoextrusion Dies for Thermoplastics
• 5.1 Dies with Circular Exit Cross Section -- 5.1.1 Designs and Applications -- 5.1.2 Design -- 5.2 Dies with Slit Exit Cross Section -- 5.2.1 Designs and Applications -- 5.2.2 Design -- 5.3 Dies with Annular Exit Cross Section -- 5.3.1 Types -- 5.3.2 Applications -- 5.3.3 Design -- 5.4 Formulas for the Computation of the Pressure Loss in the Flow Channel Geometries other than Pipe or Slit -- 5.5 Dies with Irregular Outlet Geometry (Profile Dies) -- 5.5.1 Designs and Applications -- 5.5.2 Design -- 5.6 Dies for Foamed Semi-finished Products -- 5.6.1 Dies for Foamed Films and Sheets -- 5.6.2 Dies for Foamed Profiles -- 5.7 Special Dies -- 5.7.1 Dies for Coating of Profiles of Arbitrary Cross Section -- 5.7.2 Dies for the Production of Profiles with Reinforcing Inserts -- 5.7.3 Dies for the Production of Nets -- 5.7.4 Slit Die with Driven Screw for the Production of Slabs -- 6 Coextrusion Dies for Thermoplastics -- 6.1 Designs -- 6.1.1 Externally Combining Coextrusion Dies -- 6.1.2 Adapter (Feedblock) Dies -- 6.1.3 Multi-Manifold Dies -- 6.2 Applications -- 6.2.1 Film and Sheet Dies -- 6.2.2 Blown Film Dies -- 6.2.3 Dies for the Extrusion of Parisons for Blow Molding -- 6.3 Computations of Flow and Design -- 6.3.1 Computation of Simple Multi-layer Flow with Constant Viscosity -- 6.3.2 Computation of Coextrusion Flow by the Explicit Finite Difference Method -- 6.3.3 Computation of Velocity and Temperature Fields by the Finite Difference Method -- 6.3.4 Computation of Velocity Fields in Coextrusion Flows by FEM -- 6.4 Instabilities in Multi-layer Flow -- 7 Extrusion Dies for Elastomers -- 7.1 Designs of Dies for the Extrusion of Elastomers -- 7.2 Fundamentals of Design of Extrusion Dies for Elastomers -- 7.2.1 Thermodynamic Material Data -- 7.2.2 Rheological Material Data -- 7.2.3 Computation of Viscous Pressure Losses
• 7.2.4 Estimation of the Peak Temperatures -- 7.2.5 Consideration of the Elastic Behavior of the Material -- 7.3 Design of Distributor Dies for Elastomers -- 7.4 Design of Slotted Discs for Extrusion Dies for Elastomers -- 7.4.1 Computation of Pressure Losses -- 7.4.2 Extrudate Swelling (Die Swell) -- 7.4.3 Simplified Estimations for the Design of a Slotted Disc -- 8 Heating of Extrusion Dies -- 8.1 Types and Applications -- 8.1.1 Heating of Extrusion Dies with Fluids -- 8.1.2 Electrically Heated Extrusion Dies -- 8.1.3 Temperature Control of Extrusion Dies -- 8.2 Thermal Design -- 8.2.1 Criteria and Degrees of Freedom for the Thermal Design -- 8.2.2 Heat Balance at the Extrusion Die -- 8.2.3 Restrictive Assumptions for the Development of a Model -- 8.2.4 Simulation Methods for the Thermal Design -- 9 Mechanical Design of Extrusion Dies -- 9.1 Mechanical Design of a Breaker Plate -- 9.2 Mechanical Design of a Die with Axially Symmetrical Flow Channels -- 9.3 Mechanical Design of a Slit Die -- 9.4 General Design Rules -- 9.5 Materials for Extrusion Dies -- 10 Handling, Cleaning and Maintaining Extrusion Dies -- 11 Calibration of Pipes and Profiles -- 11.1 Types and Applications -- 11.1.1 Friction Calibration -- 11.1.2 External Calibration with Compressed Air -- 11.1.3 External Calibration with Vacuum -- 11.1.4 Internal Calibration -- 11.1.5 Precision Extrusion Pullforming (The Technoform Process) -- 11.1.6 Special Process with Movable Calibrators -- 11.2 Thermal Design of Calibration Lines -- 11.2.1 Analytical Computational Model -- 11.2.2 Numerical Computational Model -- 11.2.3 Analogy Model -- 11.2.4 Thermal Boundary Conditions and Material Data -- 11.3 Effect of Cooling on the Quality of the Extrudate -- 11.4 Mechanical Design of Calibration Lines -- 11.5 Cooling Dies, Process for Production of Solid Bars -- Index