Extrusion in brief
Extrusion involves cutting an alloyed aluminum ingot to the correct length, heating it to around 500°C and pressing it through a high-pressure die. As it passes through the tool, it takes on the new shape of the ingot – exactly according to the cross-section of the profile drawing.
At ProfilGruppen, we have four separate presses, each of which can produce up to eight profiles simultaneously. After pressing, the profiles are cooled with air and/or water, depending on the alloy. After that:
- Straightening the profiles in hydraulic equipment.
- Cut to the desired length.
- Hot-tempered at 180 °C for 5-8 hours, to increase strength by accelerating the natural hardening process of the material.
- Important restrictions and considerations.
The design of the profile must be adapted to the maximum dimensions of the press opening – it determines what can actually be pressed. The tool also plays a crucial role in the outcome. Both very large and very small profiles require special consideration in the design, for example when choosing the thickness of the material.
Manufacturing process – step by step
- Aluminum ingot intake: 8″ or 10″ in diameter. Maximum profile width is about 120% of the ingot diameter (e.g. 240 mm for 8″ ingot).
- Casting: The casting is cut to a unique length for each profile (0.4-1.4 meters).
- Heating: the ingot is heated to around 500 °C in the ingot furnace.
- Loading: The cargo is placed in the container.
- Pressurization: The press cylinder increases the pressure from 1.3-1.8 MPa to about 50-60 MPa – equivalent to up to 3200 tons at the moment of pressing.
- Pressing: The molding is pressed through the tool, which controls the shape of the profile.
- Cooling: The freshly pressed profile is cooled with air and/or water on the discharge table.
- Finishing: straightening, cutting and warping – to give the profile its final shape and strength.