2. Reasonable calculation of extrusion die size
When calculating the die hole size, the chemical composition of the extruded aluminum alloy, the shape of the product, the nominal size and tolerance, the extrusion temperature, and the linear expansion coefficient of the die material and the extruded alloy at this temperature are mainly considered. The characteristics of the geometric shape and its changes during stretch straightening, the size of the pressing force and the elastic deformation of the mold.
For profiles with large wall thickness differences, the thin-walled parts and the sharp-pointed corners that are difficult to form should be appropriately enlarged. For the die-holes of flat and wide-wall profiles and wall profiles with large aspect ratio, the size of the purlins can be designed according to the general profile, and the thickness of the webs, in addition to the factors listed in the formula, must be considered. Elastic deformation and plastic deformation and overall bending, far from the center of the extrusion tube and other factors. In addition, the extrusion speed, the presence or absence of the traction device, etc. also have a certain influence on the die hole size.