Know-How

Bulk, Solid and Melt Density: How to Calculate These Values and Why They Matter — Part 1 of 2

How much resin is contained within a bucket, gaylord or hopper? That depends on the bulk density — a figure you need to learn how to calculate due to its impact on everything from storage and conveying to drying and molding.

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Sheet Extrusion 3 Dec 2024

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.

Know-How 26 Nov 2024

How to Configure Your Twin-Screw Barrel Layout

In twin-screw compounding, most engineers recognize the benefits of being able to configure screw elements. Here’s what you need to know about sequencing barrel sections.

Extrusion 15 Nov 2024

What's Restricting My Output Rate?

In a single-screw extruder, it could be an improperly designed barrier flighted entry section. Here’s why.

Injection Know How 11 Nov 2024

Important Factors and Approaches to Estimating Residence Time in Injection Molding

Residence time can have a dramatic impact on part quality and production efficiency but determining its value can be tricky. Use these methods and formulas to accurately measure residence time and enable it to inform everything from scheduling jobs to optimizing a process.

Injection Molding 30 Oct 2024

A Systematic Approach to Process Development

The path to a no-baby-sitting injection molding process is paved with data and can be found by following certain steps.

Tooling 28 Oct 2024

What You Need to Know About Leader Pins and Bushings

There’s a lot more to these humble but essential mold components than you might suspect. Following the author’s tips could save much time, money and frustration.

Mold Maintenance 2 Mar 2020

Solving Issues with Gloss

Your problem may be related to tooling, material, processing, or combinations thereof. Here’s how to find the root cause.

Extrusion Know How 2 Mar 2020

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.

Materials 2 Mar 2020

Is It Glass Filled or Glass Reinforced?

Here is how to tell the difference.

Extrusion Know How 18 Oct 2024

How to Decrease the Extrudate Temperature in Single-Screw Extruders

In many cases, decreasing the discharge temperature will improve product quality and perhaps even boost rate. Here are ways to do it.

Injection Molding 14 Oct 2024

Get the Most From Fiber-Reinforced Thermoplastic Composites Parts

There are five specific areas that designers and manufacturers need to consider to realize the potential of these unique materials.

Materials Know How 11 Oct 2024

Polymer Science for Those Who Work With Plastic — Part 1: The Repeat Unit

What are the basic building blocks of plastics and how do they affect the processing of that material and its potential applications in the real world? Meet the repeat unit.