In comparison, chromite has a higher temperature resistance and better. These attributes make this mold material especially suitable for mold areas with high material accumulation and materials with high temperatures, for example, in. On the one hand, chromite guarantees high quality for specific products; on the other hand, this increases the cost of molding material if there is no internal circulation system. Chromite is considerably more expensive than.
The mixture of chromite and which arises inevitably at the usual, leads to problems with the quality of the and increased costs when reused. For this reason, these varieties must be separated and put back into the mold material cycle separately.
As chromite is slightly magnetic, modern systems separate chromite to result in exceptionally pure materials flowing back into the mold and production process as a replacement.
The flowable and dust-free system is separated into four steps using combined technology of two magnetic stages, separation and the corresponding sieving technique. The first separation step is separated from the magnetic particles by a high-power magnetic drum. They can be reused directly in the cycle. The so-called magnetic fraction passes through the next three steps of the plant, where the chromite is refined. During this process, undesired materials, such as risers, are primarily eliminated from the.
Chromite is sometimes used as whereby is used as but also as a mold material for production. Consequently, in addition to binder residues, the accumulated use also contains valuable chromite to be reclaimed during use. The separation is carried out using a magnetic separator as the chromite can be weakly magnetized. Permanently magnetic, high-intensity walls are used in combination with cleaning and dust-removal devices.
The magnetic separator has two consecutive separation steps. In the first step, magnetic metal parts are removed, while in the second step, the chromite is separated from the hybrid materials with a stronger magnet. If necessary, the third step with an even stronger magnetic field can be reclaiming almost 100 % pure. Each magnetic roller has a magnetic disk, whereby the magnetic field strength is adapted to suit the material which is to be separated. The use of permanent magnets requires only a low amount of electricity compared with electromagnets. A vibrating trough allows them to flow over the whole width of the first. The conveyor belts are made of thin but solid material. When the belt runs over the magnetic roller, the magnetic components stay stuck to the belt. As the does not come into contact with the magnetic roller, it does not experience any wear. Positive air pressure between and the magnetic rollers prevents dust from getting in.