Exclusive Screw Technology Optimized by Milacron for Significantly Higher Melt Rates

The secret to higher productivity in your process? Faster, more efficient melting made possible by the Barr Variable Barrier Energy Transfer screw – available exclusively from Milacron Aftermarket.  For even the most demanding applications, our team customizes a solution that produces better mixing and melting, lower energy costs and processing productivity improvements of up to 50 percent.

A Superior Screw

  • Higher production rates
  • Lower melt temperatures
  • Improved mixing
  • Reduce shear energy input
  • Improved energy efficiency
  • Increased conductive melting
  • No hot spots and no splay
  • Adaptable to a wide variety of resins

The Barr VBET Difference

Typical barrier screws largely keep the unmelted and melted resin separated, with very thin melt film. This creates high melt temperatures and requires cooling the molten polymer downstream. The Barr VBET keeps the unmelted pellets mixing with fresh melt, yielding significantly higher melting rates because its surface area for unmelted pellets far exceeds the solid bed surface area of a conventional screw.

How the Barr VBET Works

The Barr VBET screw channel is divided into two sub-channels. The particles continuously change their positions as they flow from one sub-channel into another sub-channel along the screw. A particle in the surface layer of one sub-channel ends up in the center layer of the other sub-channel. This Solid/Melt Flow mechanism gives uniform melt quality and uniform melt temperature by continuously mixing the melt, eliminating undesirable hot spots inside the screw channel.

Barr VBET Advantages:

  • Unique, low-shear design geometry. Nearly half of screw’s length functions as an energy transfer section, providing an increase in conduction melting of almost 30%.
  • Reduced heat loss and lower melt temperature. The Barr VBET energy transfer section melts 30-50% of the polymer by conducting heat from the previously melted polymer, eliminating the need for downstream cooling.
  • Uniform melt quality and temperature. The Barr VBET screw channel is divided into two sub-channels. The particles continuously change their positions as they flow from one sub-channel into another along the screw. This solid/melt flow mechanism continuously mixes the melt, eliminating undesirable hot spots.
  • Substantially higher processing power. The mixing/melting section of the Barr VBET Screw is 30-50% longer than a regular screw. The conductive melting capacity of the Barr VBET Screw can process a wider variety of resins, including high-viscosity materials (including PVC) and high melt-flow rate materials.