Jewel sand features
- Spherical grain shape: the grain shape is close to the true circle, the surface is smooth, and there is no concave and convex veining. Its fluidity and filling properties are good, and good formability and casting mold strength are obtained. Good collapsibility, easy to clean sand. Less binder is used than other granular casting sand molds.
- Low thermal expansion rate: The low thermal expansion rate is the same as that of special sands such as chromium ore, so the dimensional accuracy of the production castings is high, the cracking and surface defects are few, and the casting yield is high.
- Good crushing resistance: Baozhu sand has good compactness, high strength, even if it is recycled, it is rarely broken, reducing the pollution of dust in the casting production process to the production environment, good recyclability, reducing industrial waste emissions, and conducive to environmental protection.
- Good fire resistance: the main component is alumina, so the fire resistance is very good. Refractory ≥ 1850 °C can be applied to casting various metals and alloys.
- Small bulk density: small bulk density, compared with chrome ore and zircon sand (density) Baozhu sand has a lower density, the weight of sand used when making the same model (core) is much lower than that of chrome ore, zircon sand, correspondingly reduce production costs, according to the volume ratio, only 50% of chrome ore, 30% of zircon sand.
- Neutral material: PH value 6-7, stable chemical properties, acid and alkali erosion resistance, low acid consumption value. Both acidic and alkaline binders can be used.
Compared with chromite ore and zircon, its price is only zircon sand, chromite ore 25 – 50% 。 At the same time, because the sand grain is spherical and its surface area is small, the amount of resin added can be reduced by 30-50%, and the amount of water glass added ≤ 4%; And reduce the casting defects caused by the binder, and improve the yield of castings
