Plastics Extrusion

Extrusion is a continuous process through which parts of a fixed cross-sectional profile are made. Material is fed through a hopper into an extruder, essentially a rotating screw surrounded by a heated barrel, where it is mixed, melted and pumped through a die. The die gives the part its shape. Types include film extrusion, sheet extrusion, pipe, profile and tubing extrusion.

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Plastics Technology Year in Review: Your Favorite Reads of 2024

A year-end review of the top stories showcasing industry trends, advancements and expert insights. Revisit the articles that captured the attention of the plastics community.

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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.

Extrusion Know How 24 Sep 2024

Why Are There No 'Universal' Screws for All Polymers?

There’s a simple answer: Because all plastics are not the same.

best practices 26 Aug 2024

What to Know About Your Materials When Choosing a Feeder

Feeder performance is crucial to operating extrusion and compounding lines. And consistent, reliable feeding depends in large part on selecting a feeder compatible with the materials and additives you intend to process. Follow these tips to analyze your feeder requirements.

Extrusion Know How 24 Jun 2024

Understanding Melting in Single-Screw Extruders

You can better visualize the melting process by “flipping” the observation point so the barrel appears to be turning clockwise around a stationary screw.

Film Extrusion 13 May 2024

Follow These Tips to Fire Up Your Cold Blown Film Line

Firing up a cold blown-film line after a shutdown involves multiple pieces of equipment that all interact. Here’s a look at those components individually and some best practices on how to get your line up and running as quickly and safely as possible.

Pipe, Profile & Tubing Extrusion 20 Dec 2023

How to Select the Right Tooling for Pipe Extrusion

In pipe extrusion, selecting or building a complementary set of tooling often poses challenges due to a range of qualitative factors. Here’s some guidance to help you out.

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Guill - World Leader in Extrusion Tooling

Latest Extrusion News And Updates

Film Extrusion 25 Dec 2024

LG, Reifenhauser Combine on MDO Push

Resin and machinery companies also aim to look for further downgauging opportunities.

Injection Molding 30 Oct 2024

Ether-Based TPUs for Broad Range of Industry Applications

BASF’s Elastollan 1400 TPU series can be used for applications ranging from railway pads, hoses and profiles to show soles.

Extrusion 28 Oct 2024

2025 Extrusion Conference Shifts to Standalone Event in Boston

The annual technical conference organized by Plastics Technology magazine was scheduled to co-locate with the PTXPO trade show next March. Both events will now occur independently.

Pipe, Profile & Tubing Extrusion 23 Oct 2024

‘Revolutionary’ Extrudable PPS for Sustainable Piping

Syensqo’s Ryton PPS XE-5000NA boasts exceptional chemical and permeation resistance.

Injection Molding 17 Oct 2024

Insight Polymers & Compounding Unveils New Conductive Products Line

The new conductive products line will also be produced for injection molding and extrusion.

Film Extrusion 8 Oct 2024

New Owners for Alpha Marathon

After bankruptcy, new group purchases intellectual property and forms Alpha Marathon Film Extrusion Technologies.

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Featured Posts

close up on technology 27 Nov 2024

New Screw Boosts Mixing, Enhances Polymer Properties

Device mixes at the ‘molecular level,’ inventor says, to boost mechanicals and in some cases make pre-drying redundant.

processor's edge 18 Nov 2024

Leading Cast Film Processor Adding Blown Film Capacity

Malpack adds two multilayer blown film lines for agricultural, stretch hood and shrink films.

Extrusion Know How 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.

close up on technology 13 Nov 2024

Materials Suppliers Team on PFAS-Free Solutions

Baerlocher PFAS-fee process aid passes muster in resin manufacturer’s testing on production-sized blown film line.

Sheet Extrusion 1 Nov 2024

Making Gains in the Drain Game

AWD blends extrusion and thermoforming technologies with plenty of home-brewed equipment and processes to keep water away from where it isn’t supposed to be.

best practices 22 Oct 2024

Part 2 Medical Tubing: Use Simulation to Troubleshoot, Optimize Processing & Dies

Simulation can determine whether a die has regions of low shear rate and shear stress on the metal surface where the polymer would ultimately degrade, and can help processors design dies better suited for their projects.

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Glycon's DM2: The High Performance Feedscrew

FAQ: Extrusion

How Much L/D Do You Really Need?

However, there are actual limits on increasing output as L/D is increased. Usually these limits are due to the inability of the feed section to deliver more polymer. On smaller-diameter screws, that limit often is determined by screw strength. On small screws you can only go so deep in screw channels before the screw is over torqued and fails. On larger extruders, the efficiency of feeding decreases as the channels get deeper until there is no further increase in output.

How Do I Select the Right Cooling Stack for Sheet Extrusion?

There are four main things to consider in selecting the correct stack for your application: the overall cooling capacity, the products to be processed, the mechanical capability, and the rolls’ internal design. Considering just the cooling capacity, the top roll is there to set the sheet thickness as well as its uniformity.

How Do You Know if Your Screws Are Working Properly?

One of the most useful evaluations is the relatively simple calculation of drag flow. Drag flow is simply half the volume of one turn of the metering section per second at a specific screw rpm, which, when multiplied by a units conversion and the melt specific gravity of the polymer, is a very accurate approximation of the output in lb/hr at no head pressure.