Maro Publications

Barrier Screws

Notes

*5/23/2012

Maro Topics

Comments

Articles with Abstracts

Articles without Abstracts

Books.htm

Patents with Abstracts

Patents without Abstracts

Extrusion

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 

Notes

“Single-screw extruders are most widely used in processing plastic materials for melting solid plastic into molten state, or melt, suitable for forming into desired shapes. The performance of an extruder basically depends on the geometrical features of the screw. Among various types of special screws developed to improve the extruder performance, barrier screws utilizing a barrier flight have been most successful. The barrier flight with a tight clearance divides the screw channel into a solid channel and a melt channel. Only molten plastic material can flow over the barrier flight from the solid channel into the melt channel.

Although the barrier screws significantly improve the extruder performance, all of them have some undesirable structural features and their structures still can be improved. Problems encountered with previous barrier screws include, but are not limited to, blockage to solid bed movement, degradation of plastic material at dead-spot or in deep melt channel, small solid bed pieces entering melt channel from solid channel with a large depth at the end, overheating of melt at the end of solid channel with a very shallow depth at the end, poor metering capability of very deep melt channel at the end, and undesirable melt distribution from deep melt channel into shallow metering channel in the direction opposite to drag flow.”

[Chung, US Patent 8,177,413 (5/15/2012)]

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

In this day of overworked technical people, keeping up is nearly impossible.  Maro's mission is to help keep up in as little time as possible.  Bookmark this page and check it often.  You will be surprised what can be picked up in just a few moments spent each day.

These pages list the links as they are found.  Some will abstracted and added to Maro Topics. (RDC 2/7/2012)

 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Roger D. Corneliussen
Editor
www.maropolymeronline.com

Maro Polymer Links
Tel: 610 363 9920
Fax: 610 363 9921
E-Mail: cornelrd@bee.net  

***********************************

Copyright 2012 by Roger D. Corneliussen.
No part of this transmission is to be duplicated in any manner or forwarded by electronic mail without the express written permission of Roger D. Corneliussen
**************************************

* Date of latest addition; date of first entry is 5/23/2012.