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

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Twin Screw Compounding Seminar, 2 day Seminar

May 8-9, 2013
Sheraton Sand Key Resort Clearwater Beach, FL
Phone: 727-595-1611

by Chris Rauwendaal

Printable Outline

About the Seminar

The seminar covers twin screw extrusion compounding in a broad sense.  Material issues will be covered as well as machinery issues.  Various types of compounders will be discussed; however, the main focus will be on co-rotating twin screw extruders.  Functions of a co-rotating TSE will be discussed in detail to develop a good understanding of what happens inside a TSE and how the process can be influenced by process conditions and machine geometry.

Screw design for TSE will be discussed in detail.  Also, scale-up of TSE will be covered with several examples.  Operation and optimization of TSE will be part of the seminar.  Troubleshooting will be an important section of the seminar.  Attendees are encouraged to bring extrusion problems to the seminar so that these can be discussed in the troubleshooting section.  Finally, maintenance issues will be covered such as gear box maintenance, screw and barrel sections, and preventive maintenance.

Who Should Attend this Seminar

This is designed for technicians and engineers that work on twin screw compounders and for maintenance personnel.  They will learn to set up and run the machine correctly and to optimize the process.  Attendees will learn how to correctly arrange screw elements along the shaft to achieve certain process objectives.  Attendees will also learn troubleshooting techniques and to recognize and solve various extrusion problems.  People involved in maintenance will learn proper maintenance procedures and how to set up preventive maintenance.

Testimonial From Previous Seminars

Course Description

Plastics compounding

  • What is plastics compounding?
  • Compounding machinery
  • Plastics used in compounding
  • Fillers used in compounding
  • Direct extrusion
  • Starve feeding vs. flood feeding
  • Degree of fill


 Twin screws for compounding

  • Twin vs single screw extruders
  • Co-rotating extruders
  • Counter-rotating extruders
  • Barrel heating and cooling
  • New TSE developments

Functions of co-rotating TSE

  • Feeding and solid conveying
  • Melting
  • Melt conveying
  • Mixing
  • Distributive mixing
  • Dispersive mixing
  • Degassing
  • Viscous dissipation
  • Pressure generation
  • Computer simulation


Screw design for co-rotating TSE

  • Basic screw geometry
  • 1-, 2-, and 3-flighted screws
  • Basic geometrical relationships
  • Conveying elements
  • Mixing elements
  • Special screw elements
  • Screw design principles
  • Proper assembly of screw elements
  • Screw design examples
  • Materials of construction
  • Coatings and surface treatment
  • Computer aided screw design

Course Description (continued)

Scale-up of co-rotating TSE

  • Volumetric scale-up
  • Specific energy consumption
  • Shear rate
  • Heat transfer
  • Residence time
  • Examples


Operating twin screw extruders

  • Safety issues
  • Starting the extruder
  • Screw speed and degree of fill
  • Temperature controllers
  • Current limit protection
  • Shut-down


Troubleshooting TSE

  • Mechanical problems
  • Screw wear
  • Barrel wear
  • Overloading the motor
  • Excessive torque on screws
  • Functional problems
  • Venting problems
  • Feed problems
  • Pressure development
  • Poor mixing
  • Quality problems
  • Poor dispersion
  • Degradation
  • Filler agglomeration


Maintenance guidelines

  • Safety issues
  • Gear box maintenance
  • Screw drive motor
  • Vacuum system
  • Screw and barrel sections
  • Preventive maintenance



Books authored by Chris Rauwendaal:

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