Abstract
This paper delves into the extrusion technology of "One Die with Multiple Holes" for aluminum profiles, encompassing the production process, temperature control of aluminum billets and dies, extrusion speed control, die design and manufacturing, advanced production equipment, as well as common issues encountered during the extrusion process and their solutions. This technology significantly enhances product yield, production efficiency, and profile quality, aligning with national policies on energy conservation and emission reduction, and playing a pivotal role in the sustainable development of enterprises.
Keywords
One Die with Multiple Holes; Temperature Control; Die Design; Extrusion Equipment
1. Die Design and Manufacturing
In the design of "One Die with Multiple Holes," optimizing the hole layout is crucial. The strength of the steel material must be considered to avoid excessively large or small hole spacings. While maintaining a symmetrical layout, horizontal placement of holes is recommended. When vertical placement is necessary, the holes should be staggered. High-precision equipment is essential for die processing, with CNC machining centers used for the tap hole and welding chambers to achieve the required accuracy, and slow wire-cut machines for the cavities to ensure verticality, parallelism, and surface finish.
2. Control of Extrusion Production Process
2.1 Process Parameters
Billet Temperature: For multi-hole flat dies, it ranges from 420-480°C, with a stepped cooling method applied. For multi-hole porthole dies, it is 430-500°C, following a similar cooling approach.
Die Temperature: Maintained between 430-480°C.
Charging Well Temperature: Typically 410-440°C, with the upper limit preferred.
Exit Temperature: Controlled at 520-580°C, as deviations can impact profile hardness and quality.
2.2 Process Operation Standards
Billet Heating: Conducted in a billet furnace with zoned temperature control, typically decreasing from the entrance to the exit.
Die Heating: Completed within 6 hours, including die pads and sleeves, avoiding overheating to preserve surface quality and extrusion performance.
Extrusion Process: The die must be removed from the furnace and used for extrusion within 3 minutes to prevent temperature differences. The first billet is extruded without venting, using a short billet (200-500mm), starting at "0" segment and gradually increasing speed. High-temperature plates protect the exit surface, and graphite sheets separate profiles to prevent scratches and damage. Traction force is adjusted intermittently to maintain dimensional accuracy. Initial billets require higher traction, which is reduced once extrusion stabilizes. Extrusion speed is typically 30-40m/min, depending on profile dimensions. Quenching (air or water) is strictly performed according to alloy specifications. Avoid unnecessary stoppages; if necessary, reheat the porthole die to 480-500°C or preferably re-bake it to prevent wall thickness variations and die damage.
2.3 Control of Exit Profile Temperature and Speed
Adjust billet heating based on exit profile temperature, maintaining it within 510-570°C.
Temperatures below 510°C can lead to insufficient hardness, while above 570°C may cause tearing or die damage.
Immediately reduce billet and extrusion speeds if the profile surface darkens, indicating excessive temperature.
Operators must constantly monitor billet and exit temperatures, profile surfaces, and equipment operation, stopping immediately in case of abnormalities to prevent die damage.
3. Extrusion Equipment for "One Die with Multiple Holes"
Successful implementation of this technology requires not only stable extrusion presses and high-quality dies but also advanced supporting equipment such as double-traction machines with flying shears, efficient billet furnaces, and hot-shearing technology for long billets, enhancing overall production efficiency and stability.
4. Conclusion
As extrusion processes continue to improve, the "One Die with Multiple Holes" technology has demonstrated remarkable potential in enhancing production efficiency, yield, and profile quality. Due to variations in equipment, die materials, and processes among enterprises, long-term experimentation and experience summarization tailored to individual characteristics are invaluable for industry learning and adoption.
