Since the online aluminum liquid purification device was put into use, it has been operating stably and has a significant purification effect on the aluminum alloy solution. The outgassing rate has reached more than 60%, which has improved the qualified rate of aluminum product quality.
Features of online liquid aluminum purification device:
- The box has a steel structure, and appropriate reinforcing ribs are added.
- Between the steel shell and the working layer, aluminum silicate fiber products and non-asbestos calcium silicate board are used for composite insulation, and its thermal conductivity is extremely low, which has the function of insulation and buffering the expansion of the working layer.
- During the casting process, the working layer of the box body is always immersed in the high-temperature aluminum liquid, so a special high-aluminum castable must be used as the working layer of the box body.
The structure of the degassing box avoids the short circuit of the aluminum liquid, that is, it does not pass through the inert bubble-intensive area, but flows into the filter box from a shortcut, which affects the purification effect. When designing the inner cavity, it is necessary to ensure that the molten aluminum passes through the following route: molten aluminum inlet-the intersection of the molten aluminum surface and the graphite shaft-the graphite rotor-the molten aluminum outlet. The contact area between molten aluminum and bubbles is large, and the contact time is long, and a good purification effect can be achieved.
In order to ensure that the box body always maintains a slight positive pressure during the purification operation process, and at the same time to prevent outside air and water vapor from entering the box body, the aluminum inlet and the aluminum outlet are designed to be sloped, so that the upper edge of the inner side of the box is equal or slightly lower than Lower edge of the outer mouth. The aluminum liquid is always in a sealed state in the degassing box, reducing the contact with the outside air and avoiding the reaction with water vapor again.
Except for the air cavity to ensure a reasonable working volume, the remaining molten aluminum channels are kept to a minimum volume to minimize the flow of molten aluminum between different casting times.