Use of a shadowing tongue to reduce elastic die deflections

In aluminium extrusion an additional tongue can in principle be placed in the metal stream above a die tongue to reduce the loads exerted from the metal stream onto the die tongue itself. The presence of such a shadowing tongue thus could give less elastic bending of the main die tongue. This principle have been analysed by means of a two-dimensional FEM-model using the software DEFORM 2D. The study reveals that the presence of a secondary shadowing tongue will reduce the bending load on the primary die tongue placed below. The load reductions for the die tongue have been quantified as it is predicted for different configurations of the shadowing tongue.