The foundry applications of Chromite Sand
Chromite ore is a type of spinel ore containing chromium oxide, iron oxide, and small amounts of silicon and calcium. After breaking into small particles, it becomes sandy and is also known as chromite sand. Cr2O3 content min 46% chromite sand is for foundry. Due to its high refractory temperature, fast thermal conductivity and cooling rate, solid-state sintering, and low coefficient of expansion, chromite sand is considered a good casting sand and surface sand for steel castings.
Chromite sand can be used in different materials and casting processes, with specific application ranges as follows:
1. Large scale thick walled casting.
Chromite sand combined with sand casting, furan resin self hardening sand, water glass self hardening sand and other processes are used for large volume and weight cast iron and steel castings. It can cool the castings in a predetermined order. It is conducive to improving the internal tightness of the castings and enhancing their strength.
In addition, for the process of using silica sand, chromium ore sand can be used as surface sand instead of silica sand in key areas where porosity and veins are prone to occur. That can effectively prevent casting defects such as cracks and porosity. The Fineness are chromite AFS40-45, AFS45-55, etc.
2. Lost foam casting.
In lost foam casting, using coarse sand such as chromite AFS25-30 AFS30-35 can prevent defects such as sand inclusion and sticking caused by quartz sand casting. Used for manufacturing castings such as valves and impellers made of high chromium cast steel and high manganese steel materials.
3. Shell mold casting.
Chromite sand can be used as a core sand material for complex components in shell casting, making sand cores. Used for producing high-precision, smooth surface 304 / 316 stainless steel castings and carbon steel precision castings. Molding sand chromite sand can effectively prevent the problem of sand sticking in the inner cavity of castings.
4. Sand casting.
Chromite sand can also be used for sand casting, such as sand casting, water glass self hardening sand casting, etc., to produce various large, medium, and small parts, such as pump bodies, pipelines, valves, etc.
5. Low pressure casting.
Chromite sand can also be used for low pressure casting, suitable for producing small and medium-sized complex shaped parts, such as automotive engine cylinder heads, crankcases, etc.
6. Casting sand filling material.
Chromium ore sand has a good quenching effect and can replace cold iron as a cooling material in the sand box. The commonly used model is chromium ore sand 10-20#.
Overall, chromium ore sand can be used in various casting processes, with a wide range of applications to produce high-precision, high-performance, and high-strength castings. It is worth noting that chromium ore sand is not suitable for the production of alloy castings with low pouring temperatures.
