The barrier screw has a extra flank in the plasticizing zone. This extra flank creates a barrier that separates the solid particles from the melt. the distance between the flank and the barrel is so small that solid particles can’t get through it. Only after the solid particles are melted down they can flow to the next part of the screw.
The barrier screw offers a great heat transfer from barrel to plastic. Solid particles in the melt are prevented which limits the possibility of blockage in the injection channel.
The barrier screw is ideally suited for usage with short cycles with high dosing rates, and thereby still achieve an optimal degree of homogenization.