February 2015 ISSUE

January 2015 |
COVER STORY

EXTRUSION: Avoid General ‘Pump Ratios’ On Two-Stage Screws

Instead, rely on basic data and calculations to determine the proper depth of the first and second metering sections
#processingtips #bestpractices #screws

FEATURES

Packaging

Coextruding Blown Film Needs Deeper Understanding of Resin Rheology & Die Design

More film processors are investing in lines with nine or more layers. With more resin possibilities and combinations coming into play, it’s important to learn more about material rheology and compatibility, as well as die design.


Post-Industrial

Energy-Efficient Granulating

Granulators are notorious energy hogs, but motors and designs have improved energy efficiency over the years. Proper selection and maintenance can also do a lot to avoid wasted energy cost.
Know How

EXTRUSION: Avoid General ‘Pump Ratios’ On Two-Stage Screws

Instead, rely on basic data and calculations to determine the proper depth of the first and second metering sections
Molds & Tooling

Five Steps Toward Better Plug Assists

With careful planning and adherence to best practices, crafting the right plug assist can put you on the path to high-quality, repeatable parts.
Know How

INJECTION: First to Second Stage Transfer: Should There Be ‘Bounce-Back’?

How much screw ‘jumping’ or bounce-back can your process tolerate? The answer is no surprise: It depends
Injection Molding

Know 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.
Testing

MATERIALS: Analysis Gone Wrong

A lot of resources are devoted each year to trying to figure out why products fail. Sometimes it’s because no one involved in a project realizes the data provided was wrong.
Micro-Molding

Micromolding Gets Bigger at Tessy Plastics

Micro parts are a tiny but fast-growing segment of its custom molding business, with potential to expand beyond the medical sector.
Injection Molding

Robot End-of-Arm Tooling: Making a Big Difference

Often overlooked as a small part of an automation system, clever end-of-arm tooling techniques and designs can improve part quality, heighten efficiency, and eliminate headaches for any molder.


Tooling Know How

TOOLING: Ejectors: Watch That ‘Unsupported Length’

It may be an unfamiliar term, but it’s the key to preventing ejector-pin deflection and breakage