PSI-Polymer Systems Inc. Introduces New Line of 12” Drop-In Replacement Screen Changers for Large Extruder Applications Conover, NC (March 9, 2015)

PSI-Polymer Systems has recently placed a massive new 12” slide plate screen changer into production with a leading global material supplier. The screen changer was supplied as a retrofit for another company’s model, and designed to be a drop-in replacement unit.  The new PSI screen changer dramatically improved the machine’s output and efficiency.

The old screen changer the company had been using would constantly weep polymer from the soft alloy seals, requiring manual adjustments daily or weekly with a hydraulic ram.  This polymer leakage created significant safety concerns and housekeeping issues.  Replacement parts for the seals, which were designed in the 1960s, carried high price premiums and were not always available when needed for scheduled downtime.  When leaks develop beyond the ability of the operators to manage, these complex, often multi-component machines sometimes need a full day of downtime to fix. Twelve inch slide plates can weigh over 500 pounds, so fixing a screen changer after a leak can be an incredibly time consuming, difficult, and expensive project.

PSI’s large screen changers incorporate its patented all-steel, segmented, self-actuating seal system for leak proof operation. The seal components are machined from hardened steel and are pressure activated by the polymer melt. Seal pressure is commensurate with head pressure and frictional force of the seal against the slide plate during shift is dynamically lessened to reduce component wear. Through this design, these screen changers eliminate seal adjustment and seal maintenance over the life of the screen changer.

Another valuable feature is PSI’s “drop-in” capability.  Most existing large lines are constrained by space, power drops, piping and other hardware that cannot be easily relocated.  PSI designed the large models to drop in to the existing space envelope and connections used by the old machines.  This gives the operator the ability to swap out the old screen changer with the new PSI screen changer without having to move the extruder or downstream apparatus at all. This ease of change makes it even more worthwhile to switch out your old screen changer.

 “We frequently see old screen changers at large resin supplier’s facilities that have been running for 20-25 years and are badly in need of upgrades,” said Glenn Woodcock, President of PSI-Polymer Systems.  “This addition to our family of slide plate screen changers is made particularly with those customers in mind.  We make upgrades easy and the benefits with regard to safety, housekeeping, efficiency and reduced downtime compared to the other supplier’s models are enormous.”