processing tips
Ultrasonic Welding: Tips, Techniques, and Troubleshooting
In this collection of content, we provide expert advice on welding from some of the leading authorities in the field, with tips on such matters as controls, as well as insights on how to solve common problems in welding.
The Importance of Barrel Heat and Melt Temperature
Barrel temperature may impact melting in the case of very small extruders running very slowly. Otherwise, melting is mainly the result of shear heating of the polymer.
Read MoreFive Quick Steps Toward Better Blending
Rising costs of resins and additives, along with higher demands for quality and use of regrind, place a premium on proficient blending. Here are some steps to get you there.
Read MoreGot Streaks or Black Specs? Here’s How to Find and Fix Them
Determining the source of streaking or contamination in your molded parts is a critical step in perfecting your purging procedures ultimately saving you time and money.
Read MoreKnow Your Options in Injection Machine Nozzles
Improvements in nozzle design in recent years overcome some of the limitations of previous filter, mixing, and shut-off nozzles.
Read MoreBozzelli’s Guide To Specifying a Dryer
Here's a list of 17 things to do when looking for new drying equipment.
Read MoreThe Effects of Time on Polymers
Last month we briefly discussed the influence of temperature on the mechanical properties of polymers and reviewed some of the structural considerations that govern these effects.
Read More
A Guide to Ultrasonic Welding Controls
Ultrasonic welding today is a sophisticated process that offers numerous features for precise control. Choosing from among all these options can be daunting; but this guide will help you make sense of your control features so you can approach your next welding project with the confidence of getting good results.
The Effects of Stress on Polymers
Previously we have discussed the effects of temperature and time on the long-term behavior of polymers. Now let's take a look at stress.
Read MoreHow to Optimize Pack & Hold Times for Hot-Runner & Valve-Gated Molds
Applying a scientific method to what is typically a trial-and-error process. Part 2 of 2.
Read MoreThe Importance of Melt & Mold Temperature
Molders should realize how significantly process conditions can influence the final properties of the part.
Read MoreHot Runners: A View from the Bottom Up
Addressing hot-runner benefits, improvements, and everyday issues from the perspective of decades of experience with probably every brand on the market. Part 1 of 2.
Read MoreHow to Set Barrel Zone Temps in Injection Molding
Start by picking a target melt temperature, and double-check data sheets for the resin supplier’s recommendations. Now for the rest...
Read MoreThe Strain Rate Effect
The rate of loading for a plastic material is a key component of how we perceive its performance.
Read More
Improve Quality & Productivity With Advanced Screw Design
Most molders are still running with screw designs that haven’t changed much in 30 years. But they don’t need to.
John Bozzelli
Why (and What) You Need to Dry
Other than polyolefins, almost every other polymer exhibits some level of polarity and therefore can absorb a certain amount of moisture from the atmosphere. Here’s a look at some of these materials, and what needs to be done to dry them.
Read MoreTunnel Gates for Mold Designers, Part 1
Of all the gate types, tunnel gates are the most misunderstood. Here’s what you need to know to choose the best design for your application.
Read MoreThe Effects of Temperature
The polymers we work with follow the same principles as the body: the hotter the environment becomes, the less performance we can expect.
Read MoreSolve Four Common Problems in PET Stretch-Blow Molding
Here’s a quick guide to fixing four nettlesome problems in processing PET bottles.
Read MoreImprove The Cooling Performance Of Your Molds
Need to figure out your mold-cooling energy requirements for the various polymers you run? What about sizing cooling circuits so they provide adequate cooling capacity? Learn the tricks of the trade here.
Read More
Medical Tubing: Use Simulation to Troubleshoot, Optimize Processing & Dies
Extrusion simulations can be useful in anticipating issues and running “what-if” scenarios to size extruders and design dies for extrusion projects. It should be used at early stages of any project to avoid trial and error and remaking tooling.
A Simpler Way to Calculate Shot Size vs. Barrel Capacity
Let’s take another look at this seemingly dull but oh-so-crucial topic.
Read MoreFormulating LLDPE/LDPE Blends For Abuse–Resistant Blown Film
A new study shows how the type and amount of LDPE in blends with LLDPE affect the processing and strength/toughness properties of blown film. Data are shown for both LDPE-rich and LLDPE-rich blends.
Read MoreHow to Get Rid of Bubbles in Injection Molding
First find out if they are the result of trapped gas or a vacuum void. Then follow these steps to get rid of them.
Read MoreThe Importance of Gauging Residence-Time Distribution—Part 2
Each molecule in the molded product can have a different residence time. This variance is reflected in the Residence-Time Distribution, which you can learn how to determine below.
Read MoreTroubleshooting Pressure Fluctuations in Piston-Type Melt Filters
Piston filtration offers many advantages over other systems. While pressure fluctuations could be regarded as their weakness, there are many ways to avoid them, both from the mechanical and the process side. Small adjustment can make a huge difference in the overall performance and efficiency of the system.
Read MoreWhen to 'Adapt,' When to Retool?
That is the question pipe and tubing processors typically confront when they specify a line for one product, only to have to add to the product mix when business conditions change. Here are some tips to guide you to the right answer.
Read More
