Conveyor belt modelling in extrusion flow simulation

Technical rubber or polymer profiles are often extruded while dragging them into a water bath. However, complex or heavy profiles may require additional guiding tools. For example, geometrically complex profiles, such as PVC-window frames, require the use of calibrators for satisfying severe geometric requirements, while heavy rubber profiles, such as D-shape fenders or tire treads, require a conveying belt mainly for being able to achieve the process. Within the context of numerical simulation of extrusion flows, such a guiding tool brings an additional downstream constraint to the kinematic equation which dictates the shape of the extrudate surface. In the present paper, we propose a simple engineering approach for modelling a conveyor belt used in rubber tire tread extrusion, and we apply it to the simulation of the extrusion flow for a 3D non-symmetric profile of a viscoelastic material.