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  New and improved extrusion rate calculator

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Author Topic:   New and improved extrusion rate calculator
Tom C
Moderator

Posts: 912
From:Brodheadsville, PA USA
Registered: Jun 2001

posted December 17, 2007 10:07 AM     Click Here to See the Profile for Tom C     Edit/Delete Message   Reply w/Quote
We have improved the extrusion rate calculator with a new output model that covers a wide range of extruder diameters and materials. The calulation is based on real world results, not a theoretical model. Certain materials, such as PP, do not follow the normal trends so a tuning factor has been added for those materials.

The calculator is free to use. If you have any questions or comments feel free to contact me through the web site www.extrusiontechnicalservices.com

www.plasticextrusion.info


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Best Regards,

Tom Cunningham

[This message has been edited by Tom C (edited December 17, 2007).]

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Stephen J. Derezinski
Senior Member

Posts: 87
From:Penfield, NY, 14526, USA
Registered: Apr 2003

posted December 17, 2007 04:00 PM     Click Here to See the Profile for Stephen J. Derezinski     Edit/Delete Message   Reply w/Quote
Tom--
Very interesting to me.
I am wondering how you scale for any changes without some model involved? Especially, if the designated change is outside of you data range.
Thanks, it is very generous of you to share this with everybody.

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Steve Derezinski, Ph.D.
Extruder Tech, Inc.
steve@extrudertech.com
www.extrudertech.com

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Tom C
Moderator

Posts: 912
From:Brodheadsville, PA USA
Registered: Jun 2001

posted December 17, 2007 04:29 PM     Click Here to See the Profile for Tom C     Edit/Delete Message   Reply w/Quote
Steve,

I've got nothing on you with regards to publically available stuff. Everyone should check Steve's web site.

There all all kinds of situations that don't fit the model, but really they are only +/- 20% or so. What I have found is there are all kinds of boundries that limit what an extruder of a certain diameter can do regardless of diameter. Power, pumping ability, melting ability, heat transfer, on and on. These limits apply to polymers with extrudable viscosities, which is another boundry. The differences are corrected for melt density and barrel surface area. Seems to work well over a broad range of typical situations.

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Best Regards,

Tom Cunningham

www.ExtrusionTechnicalServices.com

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Makeit Work
Member

Posts: 2
From:USA
Registered: May 2008

posted June 26, 2008 10:33 AM     Click Here to See the Profile for Makeit Work     Edit/Delete Message   Reply w/Quote
Most dat sheets provide the specific gravity and the melt flow, but not the melt index. Where do I get this figure or how do I calculate it?

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Tom C
Moderator

Posts: 912
From:Brodheadsville, PA USA
Registered: Jun 2001

posted June 26, 2008 10:40 AM     Click Here to See the Profile for Tom C     Edit/Delete Message   Reply w/Quote
Melt index and Melt Flow Rate are the same thing.

Neither is required for the Extrusion Rate Calculator.

Melt density is automatically applied when you select a polymer, and it is not the same as the solid specific gravity. If you have a filled polymer you may need to adjust the melt density.

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Best Regards,

Tom Cunningham

www.ExtrusionTechnicalServices.com

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