Extrusion Know How
Don’t Overlook the Feed Section
Most extrusion screw designers often do not design the feed section with the same rigor as other sections. This is odd since nothing goes through the screw that doesn’t first go through the feed section.
Read MoreRegrind and Melt Pumps
Changing levels of regrind can result in unstable output. If not set up properly, a melt pump can add to this instability—the opposite of the intended effect.
Read MoreThe Scale-Up Conundrum
There are many methods used to determine scale-up based on output, but most designers do not scale the melting requirement along with the output.
Read MoreUnderstanding Screw Breakage
You might think you're over-torquing the screw, but more often than not bending is the reason.
Read MoreExtrusion: Where's the Data? The Importance of Melt Strength in Extrusion
All extrusion processes depend to some degree on the melt strength of the polymer, and this property is generally a no-show on data sheets.
Read MoreThe Cause of Catastrophic Screw Wear
Erratic feeding can be the culprit. This is not uncommon when dealing with recycled material.
Read MoreThe Limits Of Compression Ratio
Don't rely just on this value during the screw design process.
Read MoreCooling Tips for Crystalline Polymers
If a little cooling is good, is a lot of cooling better?
Read MoreThe Evolving Barrier Screw
There has been a gradual transition from the earlier Maillefer designs used in Europe to the Dray/Lawrence design using the parallel barrier design with an increased helix angle to accommodate wider channels.
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