Please visit: R. Dray Mfg. Inc. of Texas
PO Box 671326
Dallas, TX 75367 US
A mixing section with replaceable dams is said to remedy the limitations of so-called “general-purpose” injection screws.
Renowned screw designer Robert F. Dray wrote to me recently, lamenting that injection molding screw design has not received the kind of attention that the extrusion industry has paid to perfecting this fundamental processing component.
A new barrier screw has removable keys to change the dam height, allowing the screw to be tuned for highest throughput with resins as different as LLDPE and nylon, says the screw’s designer, Robert Dray, president of R.
A new mixing design has been added to the All-Purpose Valve (APV) from R.