Bentonites are used in casting industry by adding into the silica sand in ratio of 4-6%, and they prevent expansion and deformation in the mold.
It is also possible to minimize crusting in casting industry by using high quality bentonite. The bentonites to be used in this sector should have the following properties:
- Liquid limit value min. 200,
- Wet compressive strength min. 1800 g/cm2
- Wet drawing strength min. 25 g/cm2
- Swelling index min. 15 g/ cm2
- İgnition loss max. % 9,
- Lime ratio max. % 1.2
The most important feature of our product which is specifically developed for casting sector is that its crystal structure deteriorates less and the decrease in its bonding property remains limited when it is subjected to high heat loadings or high melting temperatures relative to the Calcium based Bentonites.
By means of this high thermal strength, the production in molding lines can be preserved by adding less bentonite and sand. Therefore the production errors originating from high humidity are eliminated due to the decrease in humidity rate. Furthermore, it is low cost since less waste is released to the environment due to low use.
ADVANTAGES:
1. Decrease in sand originating casting errors
2. high wet drawing strength
3. high Liquid Limit
4. preventing lumping in the molding line
5. Being able to reach desired compressibility values with less water
6. Thermal stability at high temperatures