Principle

The extrusion unit

The horizontal continuous extruder includes:

• A nitrided steel barrel, with his feed hopper. Electrical resistances controlled by static pyrometers heat this barrel. Thermocouple probes check temperature. Blowing fans remove excess heat.
• An extrusion screw made of special nitrided steel with a shape specifically adapted to the plastic material to be.
• A drive unit including a three-phase electric motor with its speed variation control unit. This motor drives the screw through a belt and pulley transmission and a gear type reducer.
• A parison head made up of a spider-pin-die-end piece assembly. Like the barrel, resistances heat the head. To inflate the parison, some air is blown through the die-pin. Changing the pin and the die gap makes it possible to modify the parison wall thickness and therefore the weight of the items produced.