Rauwendaal Extrusion engineering, Inc.
Rauwendaal Extrusion Engineering, Inc. 530.269.1082

A Polymer Process Engineering & Training Company Home of the CRD Mixing Screws

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Foam Extrusion Seminar, 3 day Seminar

May 12-14, 2014
Sheraton Sand Key Resort
Clearwater Beach, FL
Phone: 727-595-1611

by Chris Rauwendaal and James Throne

Printable Outline

About the Seminar

This seminar covers important materials, equipment, and process issues of foam extrusion in a comprehensive fashion.

The objectives of this seminar are:

What the attendees will learn:

Who should attend:

Testimonial from previous Seminars

Course Description

Basic Principles

• Mechanical properties of foams
    Std time behavior: stiffness, strength
    Long time behavior: creep, fatigue
   Short time behavior: impact
• Foamable polymers
     Morphological characteristics
     Characteristics of important resins
• Additives
• Cell stabilizers
• Other agents
• Nucleating agents
• Foaming agents
• Chemical : exo- and endo-thermics
     Physical: atmospheric,                            hydrocarbons, HCFCs
     Solubility and diffusivity
• Rheology of gas-laden melts
     Bubble mechanics
      Why does a foam stop growing?
     And why does it shrink?
    Open-celled foams

Foaming Agents
• Natural Fiber Foam Composites
     Polymer Structures
     Process of Manufacturing
     Cooling and Mixing
     Role of Cellular Structures
     Fine Cellular Structure
     Chemistry of the Foaming Agent
     Die Configuration and Extrusion
• Foaming Agent Process and Perfor-
     Foaming Agent Technologies
     Endothermic & Exothermic 

        Foaming Agents
    Gases & Nucleation
    Elastomeric Foam Design
    What 's happening in the Barrel?
    Blowing Agent Compatibility
    Blowing Agent Process
    Properties of Foam Articles
    Process Improvement using CO2
    Open Cell Foam
    Foaming agent studies
    Foaming agents in IM & Extrusion
    New Equipment Technologies

Course Description (continued)


• Twin vs. single screw extruders
• Single- vs. two-stage process
• Screw design for foam extrusion
• Melt temperature distribution
• Die design for foam extrusion
• High vs. low density foam products
• Free foaming method
• Constrained foaming method
• Microcellular foam extrusion
• Coextrusion

Thermoformability of Low-Density Thin-Gauge Sheet
• Material-Specific Die Design for Thin- Gauge Sheet
• Temperature-Dependent Internal Cell Gas Pressure During Cooling
• The Role of Sheet Aging Prior to Ther- moforming
• Factors Influencing Secondary Foam Expansion During Reheating
• Internal Cell Gas Pressure
• Temperature-Dependent Tensile Modulus
• Processing Factors Influencing Cata-
  strophic Cell Collapse

• Requirements
• Tools for troubleshooting
• Systematic troubleshooting
• Extrusion instabilities
     Frequency of instability
     Functional instabilities
     Solving extrusion instabilities
• Computer aided troubleshooting
• Case studies
     Wear problems
     Mixing problems
     Irregular cell structure
     Dimensional variation

Thermoplastic Foam Extrusion by James L. Throne is available from Hanser Publications with a discount code you receive when registration is confirmed..

Books authored by Chris Rauwendaal are available from Hanser Publications with any seminar registration for a discounted price with a code you receive when registration is confirmed :

The following book is available from REE

  • Mixing in Polymer Processing

About the Instructor:

Dr. Chris Rauwendaal has been a top seminar instructor for more than 25 years. He has taught with SPE, UWM & UC Berkeley & teaches many in-house courses. He is a well known plastics author. Chris has 30+ years experience in the plastics industry. His experience is in a wide range of extrusion operations, including fiber spinning, film, sheet, tubing, medical tubing & profile extrusion, coextrusion, and reactive extrusion. He has worked on both practical and theoretical problems such as screw & die design, troubleshooting, modeling and computer simulation, material analysis, failure analysis, etc. Chris has authored 6 books on extrusion and related fields.

Since 1990 he has been President of Rauwendaal Extrusion Engineering, Inc., a company that provides custom extruder screws and other extrusion hardware, training programs, engineering & expert witness services to the plastic industry. With screw design as his specialty, over the past 5 years REE had developed patented technologies in the following areas:
• Elongational Mixing Devices
• Mixing non-return valves
• Single screw compounding extruder
• Cooling screws for foam extrusion

For registration contact: sietske@rauwendaal.com
For seminar content contact: chris@rauwendaal.com