GrindGuide

Barrier screw

  • Barrier screw

The basic idea behind the barrier screw is to separate the solids from the melt and thus increase output while maintaining the same screw diameter. An additional bar in the plasticizing zone, the so-called barrier bar, separates the solid from the melt. The molten material can flow from the solids channel into the melt channel via the barrier web. The solid material is retained and the air, which is trapped in conventional screws during the melting process, can escape through the solids channel. The escape of unmelted solid particles from the plastifier zone is prevented and a well-digested melt is ensured, which is particularly necessary at high throughput rates and high screw speeds. The barrier screw concept offers a large number of geometric degrees of freedom and has good heat transfer to the barrel heating/cooling system in the helical shear zone. The good control of melt temperatures at high screw speeds contributes, among other things, to the low wear of the barrier screw.