ABSTRACT
This chapter focuses on the modelling of the rubber flow around a screw inside a barrel. It shows the dependence of the flow on the screw geometry and on the screw and barrel temperatures. The chapter emphasizes how people derive non linear equations from rubber viscosity modelling. It also focuses on the screw and the barrel, between the feeding hooper and the die. Starting from the usual assumption of the unrolled channel which simplifies the screw geometry, people have developed a model of rubber flow within the screw which gives quite good agreements with industrial experiments. The screw channel has an helicoidal geometry which is usual to approximate with the unrolled channel assumption. Despite the development of alternative methods extrusion remains a major process in the making up of sealing components. However rubber extrusion modelling still appears to be not that satisfactory.
