That's the question, and succinct answer, that MD Plastics Inc. (Columbiana, OH), has for injection molders who normally have to control their resin melt via decompression to eliminate stringing and drooling. MD Plastics President Michael F. Durina says his company's Mini-Shut provides an inexpensive, automatic, miniature nozzle shut-off tip that not only eliminates stringing and drooling, but also the need for melt decompression itself.
The Mini-Shut, for which a U.S. patent is being sought, was engineered to ensure repeatable part weight distribution, while also reducing surface imperfections. Designed to fit on the majority of nozzle bodies, MD Plastics says the Easy Nozzle is easy to install and remove and can run reliably at temperatures above 750F. In addition to ensuring low pressure drop and shear, the Mini-Shut also allows for the simultaneous operation of the clamp and the screw to boost productivity and can be cleaned using conventional purging methods....