What About Melt Strength?
All extrusion processes depend to some degree on the melt strength of the polymer, and this property is generally a no-show on data sheets.
Columns Published: 5/28/2013

The Cause of Catastrophic Screw Wear
Erratic feeding can be the culprit. This is not uncommon when dealing with recycled material.
Columns Published: 4/29/2013

The Limits Of Compression Ratio
Don't rely just on this value during the screw design process.
Columns Published: 3/25/2013

Cooling Tips for Crystalline Polymers
If a little cooling is good, is a lot of cooling better?
Columns Published: 2/26/2013

The Evolving Barrier Screw
There has been a gradual transition from the earlier Maillefer designs used in Europe to the Dray/Lawrence design using the parallel barrier design with an increased helix angle to accommodate wider channels.
Columns Published: 1/28/2013

Why I Still Like Analog Meters
They may not look as slick as their digital cousins, but I find them more helpful in identifying and troubleshooting extrusion problems.
Columns Published: 12/28/2012

Screw Design Is a Matter of Balance
In order to achieve a balance between feeding, melting, and pumping it’s necessary to use proven calculations and/or tested empirical data in the design of each section.
Columns Published: 11/28/2012