by Allan L. Griff, Consulting Engineer

The first simple and practical guide for extrusion people everywhere — since 1983, and updated (almost) every year — the basic facts of extrusion packed into a convenient illustrated 80-page booklet, small enough to carry with you, no long explanations, yet complete enough to teach you how an extruder works, in clear, readable language. Based on Allan Griff’s intensive seminar, “Introduction to Extrusion Technology,” this manual is designed to:

  • Train new operators, foremen, and technicians;
  • Provide background information to anyone working in extrusion;
  • Help salespeople, top management, and others to understand what goes on inside their production machines.

The Plastics Extrusion Operating Manual is available in boxes of 10 copies at $125 per box. We accept all major credit cards.

Summary of the contents below.
Translations into French and Spanish are available.

The Audio Manual is a set of two CDs, approximately 2 hours playing time, narrated by author Allan L. Griff. The Audio Manual will help you learn about extrusion in your car or wherever a CD is more convenient than a book. The Audio Manual is sold with one printed manual, which includes drawings and a supplier directory. The cost is $125, the same as a box of printed manuals. The combination of a box of 10 manuals plus the CDs is $195.

To order manuals, click here

or email: 

or call: (301)758-7788


by Allan L. Griff, Consulting Engineer

Outline of Contents

Introduction to Extrusion —mechanical and thermal principles, variables, typical values.

Drive System — motors, speed reduction and variation, thrust bearings.

Screws and Barrels — three-zone concept, L/D, pitch, compression ratio, clearances, materials of construction, special designs: Maddock, barrier, pins, grooves, vents and twin-screw systems.

The Head Zone — screens and changers, breaker plates, safety devices, measurement of pressure and melt temperature, static mixers, gear pumps.

Extrusion Dies — materials, heating, need to reduce resistance.

What Happens Inside the Barrel — feed zone: perfect bite and overbite, use of barrel heat to control wall friction, starve feeding, grooved barrels, bulky feed.

What Happens Inside the Barrel — compression zone: melting mechanism, backflow over the flights, solid bed theory, surging and use of the motor ammeter.

What Happens Inside the Barrel — metering zone: final mixing and melting, drag flow and pumping capacity, melt density, blue-screw syndrome, melt pressure measurement.

What Happens in the Head and Die — concept of resistance, back-pressure, streamlining, die lines, die temperature control, dimension control, swell, drawdown, orientation.

Setting Conditions — think in zones, not profiles; what controllers and microprocessors do.

Maintenance — 12 key areas (motor, heaters, screw, etc.), cleaning small parts.

Safety — dangers from heat, electricity, moving parts, weight, other hazards.

Start-up, Material Change and Shutdown — preheating, full or empty screw, watch vital signs, purges, disassembly and cleaning, screw removal.

Common Problems — surging, poor mixing, roughness, overeating, moisture, air, contamination.

Materials for Extrusion — explanation of melt index, quality tests for incoming materials.

Directory — websites and phones of over 350 suppliers of new and used equipment.