EXTRUSION KNOW HOW

Understanding the Influence of Screw Geometry on Melting Rate

They are not as closely connected as most processors think. Here’s why.

#MeetMeInChicago

Join us September 21-23 for a first-of-its-kind event that brings under one roof our annual Molding and Extrusion Conferences, together with the Amerimold Expo. 

Understanding Roll Deflection in Sheet Processing

Because of roll deflection, sheet stacks made for PS don’t work nearly as well with PP. One solution is to try a top roll that bends in the opposite direction.

How to Select the Right Cooling Stack for Sheet

First, remember there is no universal cooling-roll stack. And be sure to take into account the specific heat of the polymer you are processing.  

Put Science into Glass-Fiber Compounding on Single Screws

There are still companies that compound glass fibers on single screws. The process is considered an “art,” but can be made more predictable with attention to screw design, speed and length, as well the choice of mixer.

Extrusion: Follow These Tips to Get Profile Die Design Just Right

Calculating polymer flow is fairly straightforward when designing a die for a simple round profile, but as the shapes get more complicated these calculations can get extremely challenging. Here’s what you need to consider.  
#dies

General-Purpose Screws on the Comeback?

They are being specified more often for recycling applications to increase flexibility. But there is still no such thing as a GP screw and recyclers need to consider other processing approaches.
#bestpractices #sustainability

The Three Causes of Screw Wear

You run the risk of wasting time and money by not understanding what’s causing your screws to wear.

Try This Approach to Clean Up Your Recycled Material

CO2 can be used as a totally “green” solvent to remove many kinds of contamination in recycled plastics without the need for toxic solvents.

Extrusion: Solving Surging in Two-Stage Screws

This usually crops up when the two stages are not matched in output. The best solution is to install a pressure-adjusting valve at the discharge end of the extruder.

Understanding the Effect of Polymer Viscosity on Melt Temperature

Every processor should get hold of the viscosity curves for the polymers they use or contemplate using in their operations, and learn how to read them.

Extrusion: Evaluating Screw Design for Multi-Material Recycling

Since many plastic products are made of a combination of materials with very different melting points, careful consideration must be given to designing screws when it comes time to recycle these products.

Extrusion: 'Melt-Blown' Fiber: What You Need to Know to Enter the Face Mask Market

Coronavirus pandemic has made extrusion processors curious about entering the face-mask market. But melt-blown fiber is very different from most other extrusion processes and requires specialized equipment.
#bestpractices

Extrusion: The Importance of Zone 1 Barrel Temperature

Tweaking the temperature settings of the first barrel zones may not yield the desired result. In fact, they may yield the opposite. Here’s why.
#bestpractices

What You Should Know About Miniature Extrusion Screws

Very small screws have become more common with the growth of additive manufacturing. Designing such screws requires balancing their output requirements with their torque strength.

Extrusion: Important Polymer Melting Equations for Extrusion Processors

The more you know about what happens in a screw, the more you’ll be able to work with your supplier to optimize design.

Try This Lower-Cost Purging Method

You might be able to reduce purging times and save money by scheduling processing jobs in order of the increasing material viscosity. But to get started, you'll need shear rate/viscosity curves for your polymers.

How to Optimize Usage of Recycled Material

Processors need to “engineer” feeding properties similar to virgin pellets into their regrind to efficiently and economically utilize more of their scrap.
#bestpractices

EXTRUSION: Melting 101

Learn the basics on how polymer melts in a single screw. Barrel temperature plays less of a role than you might think.
#processingtips #bestpractices

Extrusion: How Much L/D Do You Really Need?

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

What You Need to Know to Get into Coextrusion

Key considerations range from determining the right extruder sizes to tooling, matching material viscosities, and lots more. Take a look.

Extruder Alignment: Important, but Only Half the Equation

The other half? Aligning and supporting downstream equipment. Here are best practices.

Understanding Viscosity in Extrusion

Both the power-law coefficient and the consistency index must be considered to calculate viscosity.