Jim Frankland President

Extrusion 28 Jan 2012

‘Wedging’ Can Cause Severe Screw Wear

In a column I wrote for the July 2011 issue, I discussed the value of conducting “forensic” examination of worn screws when they are removed for clues to design flaws.

Extrusion 27 Dec 2011

The Melting Precision of Barrier Screws

These types of screws offer more melt uniformity.

screws 18 Sep 2022

How Much L/D Do You Really Need?

Just like selecting the extruder size and drive combination, the L/D should be carefully evaluated.

Extrusion Know How 25 Oct 2011

How Fillers Impact Extrusion Processing

Their addition can significantly change the processing properties of a polymer.

best practices 30 Sep 2011

Benchmark Your Extruders For Quicker Processing Fixes

Not recognizing output reductions and resolving them quickly can cost a lot of money. Benchmarking your machines will help.

best practices 23 Aug 2011

The Truth About Barrel Heating

The main purposes of the heaters are to melt the polymer that remains in the barrel at cold startup, to assist in forming the initial melt, and to “trim” the barrel temperatures for specific purposes such as improving feed rate.

Extrusion 27 Jul 2011

Where Does Shear Heating Occur? Here’s How to Find Out

One of the least understood yet most important concepts is viscous dissipation, which is the shearing or stretching of the polymer between the rotating screw and stationary barrel, causing heat to develop in the material.

Pipe, Profile & Tubing Extrusion 27 Jun 2011

Dead Screw Talking

There's a lot you can learn by conducting a post-mortum examination of your screw.

Extrusion 31 May 2011

Screw Surging, Part III: Unfilled Discharge Section

This type of surge happens most frequently with two-stage screws when the second stage has far more capacity than the first stage. It can also happen when a screw is limited in feeding or melting, causing a partially filled metering section.