Large heavy hydroelectric ball valve gate castings are crucial components of large generator sets. These castings can weigh up to 100 tons, with a wall thickness difference of more than four times between their maximum and minimum thickness points. This generates significant stress during solidification, making them prone to hot cracking, shrinkage cavities, and sand adhesion. In such large castings, using foundry chromite sand as the core sand for alkali-phenolic resin instead of quartz sand effectively prevents sand adhesion defects and facilitates sequential solidification during casting.

Chromite sand for foundry (chromite ore sand)is a high-performance special refractory sand for steel& metal foundry, made from natural chromite (FeCr₂O₄, iron chromium oxide) via crushing, grinding, washing, magnetic separation and screening to controlled grain sizes and purity.

Chromite powder used for green coloring of glass bottles typically needs to be ground very finely. 200mesh and 325mesh chromite powders are commonly used for this purpose. For 200F chromite powder (≈74μm), particles larger than 100μm are strictly prohibited. This is not because they are impurities, but because coarse particles will cause incomplete melting, color spots, streaks, black spots, and color variations, severely affecting the appearance and quality.

Cr Sand(Chromite sand) is a natural mineral product, and its quality is closely related to the quality of the raw materials. Recently, an overseas customer arranged for a third party to conduct an inspection to ensure the quality stability of Cr Sand AFS45-50 as a raw material for refractory material Tundish nozzle block sand.

Foundry chromite sand offers a unique combination of high thermal conductivity, excellent refractoriness, low thermal expansion, and chemical inertness, making it highly advantageous for casting gray iron and ductile iron. Below is a detailed breakdown of its key benefits, tailored to these specific iron alloys:

South Africa is a core global supplier of chromium ore. It holds 35.7% of global reserves and export more than 80% of chromite sand in the world . Furthermore, Supply of chromite ore in China dependence on imported chromium ore and over 80% coming from South Africa. Almost 90% of foundry chromite sand in China imported from South Africa. This highly concentrated supply and demand structure meant that the 2026 South African floods significantly impacted global chromite sand prices. The core impacts were concentrated in the following aspects: