Profals brand new cast house is comprised of a multi-chamber furnace. One chamber is loaded with ingots and the other chamber is loaded with scrap onto a specially designated platform. High temperature exhaust air is then circulated through the scrap, which allows for the paint on the profiles to evaporate into gas. The scrap raises the temperature to about 300°C, thereby saving a massive amount of energy. The next load will then push the previous one towards the furnace bottom, paint-free, dry, and safe from humidity that can cause an explosion.
The exhaust gases pass through the heat exchange unit. This unit decreases the temperature from 1000°C roof temperature to 150°C on its way to the filter. This keeps most of the energy in the furnace, extends the filter’s life and most importantly, reduces the dioxin and other pollutants that are normally generated in a high-temperature atmosphere.
Since a high oxide level generally goes together with low product quality, our furnace is totally sealed and is rarely opened. The furnace is equipped with an O2 analyzer that controls the air/gas ratio and keep a low level of O2.
In the past, alloying, mixing, and other operations were done through open doors. In the new system, a magnetic pump and a charge well have been installed. A flow of liquid aluminum allows alloying in a perfect chemical and thermal homogeneity. Standard casting is controlled using two main methods. One method was tilting the furnace. This system is easy to control. The main disadvantage is that mechanical tilting of such a heavy-duty machine decreased its life span. The second method is by opening a tap out in the furnace bottom. This method does not require any mechanical tilting, but flow control is difficult, and can be a very dangerous operation in case the stopper cone is damaged. In order to overcome these two issues, we developed a unique method, which utilizes the circulation magnetic pump as a casting pump. A tap out on the charge well was installed. During charging of the furnace, this tap out is closed. Then, just before casting, we reduce the pump capacity, lowering metal to be below the tap out level; the plug is pulled out, and the pump is raised up, allowing the metal to reach the casting table easily. In automatic mode flow is controlled directly by the laser launder height measurement device. All of this ensures safe and accurate control, and extends the furnace life. If in the past in order to achieve a reasonable product quality most of the material had to be primary, today the situation is reversed, and most of the material is recycled. Our modern furnace ensures high quality and Envirmently friendly green Green billets . These logs are marked with a casting number enabling the best castings to be utilized for anodizing, while those of lesser quality will be transferred for painting.