Plasticising process for pure or mixed plastics and plasticising plant

摘要

Plant for plasticising pure or mixed plastics prior to moulding comprises an injection moulding machine with a barrel (2) and a screw (3) having an axially movable injection piston (7) and a melt accumulation chamber divided into two parts (5, 6) by a melt flow barrier (8) at the head of the piston (7). The vol. of the two parts (5,6) of the melt chamber are variable according to the piston (7) position. In a claimed plasticising process the polymer melt enters one or both chambers (5, 6) moving the piston backwards causing melt to flow past the barrier (8) or by conventional forward movement of the piston (7).