technology, was born from the development of an American system called "single bearing", for which Alto in 2004 has bought the licence and the software to project, make and sponsor it. The main feature of this technology is the pre-chamber which is subdivided in steps from a minimum of 3 to a maximum of 9. The dies' bearing height normally used is between a minimum of 2mm till to a maximum of 4mm, this allows to reduce their friction of a 50%, as the profile is shaped through the steps. Dropping down to the minimal the friction, we are then in condition to increase the extrusion speed, keeping, anyhow, unaffected the dies' stability.
In case of profiles with very irregular wall thickness, the traditional system due to the dies' bearing difference, emphasizes on the extruded the tonality variation, while, it has been tested, that the Multi-Step-Dies, thanks to their particular structure, reduce this surface defect. Using the same procedure, in this last period Alto makes projects for hollow profiles with the die in MsD technology obtaining remarkable results.
The benefits are
- Work-pressure in extrusion: at least 30 bars less
- Die's stability increased during the extrusion
- Production speed: up to 25-30% more