Griff Extrusion Services

Contact: Allan Griff

5101 River Rd
Bethesda, MD 20816
U.S.

Phone: 301-654-1515
Fax: 301-654-1414

Website

E-mail

Consulting Services in Plastics Extrusion
Over the last 40 years, I have served as a technical consultant in many ways. I don't represent any makers of materials or equipment, so my service is unbiased and independent. I've done some equipment development, such as screw and die design, but mostly I work with existing equipment, helping their users understand them better, to get the most quality and output from them. Some examples, in addition to training personnel, include: 

1. Direct problem solving -- raise production rate, reduce thickness variation or scrap factor, find out why the product failed in service. 
2. Materials management -- suggest quality tests for incoming resins and additives, scrap reduction and more economical re-use, propose additives to improve product performance. 
3. New product development -- product testing, analysis of competition, suggesting appropriate raw materials, equipment adaptations. 
4. Legal Services -- This is often called "expert witness" work, but we rarely go to court as witnesses, as most cases are settled privately without a full trial. I do not charge for initial phone conversations. Sometimes, I am asked to read materials or visit a location on a fee-for-service basis. In other cases, we sign an agreement: the lawyers can name me as an expert and I agree to keep everything confidential and not work for the other side. From then on, the work varies as all cases are different. Most of my legal work has been for defendants in patent infringement, accidents with extrusion machinery, and failure of extruded products. 
GRIFF EXTRUSION SEMINARS in 2003

Extrusion 101 --- Introduction to Extrusion Technology
Extrusion 102 --- Extrusion Problems and Solutions (Troubleshooting) 


Atlanta, GA -- November 12-13, 2003 (101) and November 14 (102)

Stone Mountain Inn, inside Stone Mountain Park
     
Toronto, Canada -- December 10-11, 2003 (101) and Dec 12 (102)
Carlton Place Best Western, near Toronto Airport

Chicago, IL -- January 8-9, 2004 (combined 101-102)

       Ramada Plaza, near O'Hare airport


Los Angeles, CA  -- January 19-20, 2004 (combined 101-102)
       Holiday Inn, Laguna Hills

THE PLASTICS EXTRUSION OPERATING MANUAL
by Allan L. Griff, Consulting Engineer

The first simple and practical guide for extrusion people everywhere -- the basic facts of extrusion packed into a convenient illustrated 70-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 two-day 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 sales people, 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, $110 per box prepaid or $125 per box if billing is required. We also accept American Express cards.

For a summary of the contents, please click here or scroll down.
Translations into French, Spanish, Portuguese and Russian are available.

The Audio Manual is a set of audio cassettes, four sides, approximately 4 hours playing time, narrated by author Allan L. Griff. The Audio Manual will help you learn about extrusion in your car or wherever a cassette is more convenient than a book. The Audio Manual is sold with one printed manual, which includes drawings and a suppliers directory. The cost is the same as a box of printed manuals, $110 prepaid or $125 if billed. The combination of a box of 10 manuals plus the cassettes is $180 prepaid or $195 if billed.

Use our online form to order or call (301)654-1515

THE PLASTICS EXTRUSION OPERATING MANUAL
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.

Consulting Services in Plastics Extrusion
Over the last 40 years, I have served as a technical consultant in many ways. I don't represent any makers of materials or equipment, so my service is unbiased and independent. I've done some equipment development, such as screw and die design, but mostly I work with existing equipment, helping their users understand them better, to get the most quality and output from them. Some examples, in addition to training personnel, include: 

1. Direct problem solving -- raise production rate, reduce thickness variation or scrap factor, find out why the product failed in service. 
2. Materials management -- suggest quality tests for incoming resins and additives, scrap reduction and more economical re-use, propose additives to improve product performance. 
3. New product development -- product testing, analysis of competition, suggesting appropriate raw materials, equipment adaptations. 
4. Legal Services -- This is often called "expert witness" work, but we rarely go to court as witnesses, as most cases are settled privately without a full trial. I do not charge for initial phone conversations. Sometimes, I am asked to read materials or visit a location on a fee-for-service basis. In other cases, we sign an agreement: the lawyers can name me as an expert and I agree to keep everything confidential and not work for the other side. From then on, the work varies as all cases are different. Most of my legal work has been for defendants in patent infringement, accidents with extrusion machinery, and failure of extruded products. 

If you would like to discuss any of the above services, or if there is some other way I may be of help, please call, fax or e-mail the addresses above.