The role of chromite sand in ladle drainage is mainly reflected in the following aspects:
1. Improve the fire resistance and erosion resistance of drainage sand: Chromite sand has high fire resistance and can withstand the erosion of high-temperature molten steel, ensuring that drainage sand maintains stable performance for a long time at the ladle inlet.
Its high chromium content endows it with excellent chemical stability, which can prevent reactions with iron oxide and other components in molten steel, thereby preventing thermochemical sand sticking phenomenon.
2. Improving the flowability and filling performance of drainage sand: Chromite sand particles are round and smooth on the surface, with excellent flowability. When filling the bottom water mouth of the ladle, they can be quickly and evenly distributed, forming a dense filling layer.
Chromite sand
3. Control sintering performance to ensure automatic casting rate: Chromite sand can form a sintering layer of appropriate strength at high temperatures, which not only prevents the sintering layer from being too thick and hindering the flow of molten steel, but also avoids insufficient sintering causing the sand body to float up.
4. Preventing mechanical sand sticking and vein defects: During the casting process of molten metal, chromite sand forms a dense isolation layer through solid-state sintering characteristics, effectively preventing the penetration of molten metal into the interior of the molding sand.
This feature not only avoids mechanical sand sticking problems, but also reduces the probability of defects such as surface veins and sand inclusions on castings, significantly improving the surface quality of castings.