At present, the use of fused ceramic sand is still the mainstream in the production and application of steel castings, especially in the production of large, medium and small steel castings and wear-resistant materials with high mechanical performance requirements, such as high, medium and low alloy steel, medium and high manganese steel, high chromium steel and high chromium iron castings. There are many successful cases. All manufacturers are sure that fused ceramic sand has high sintering temperature and strong cooling capacity, and the old sand is particularly easy to be regenerated. It can achieve nearly zero discharge of used sand. For example, the discharge of used sand in the bonny pearl sand process combination is about 98%, which meets the requirements of the national solid waste discharge law.
Effect of hardness difference between fused ceramic sand and sintered ceramsite on regeneration performance.
The Mohs hardness of fused ceramic sand is 8-9, and that of sintered ceramsite is 7-8.
First of all, it is necessary to analyze the force on the sand particles when the old sand is regenerated. At present, the mainstream regeneration equipment at home and abroad is semi-rigid and kneading, such as vortex centrifugal regenerator, multi axis kneading regenerator, and abrasive disc powerful kneading regenerator (new type). The main force on the sand particles is rubbing regeneration, not impact regeneration, nor stamping regeneration. Therefore, the higher the surface hardness of the original sand particles, the more wear-resistant, fused ceramic sand not only has high surface hardness, but also has good toughness.
Similarities between Fused ceramic sand and sintered ceramsite
It is a good substitute for silica sand. The common feature is that the sand shape is good, but fused ceramic sand is better. The two kinds of sand have high strength and toughness, are not easy to be damaged, and the recovery rate of old sand is high. Artificial sand can reduce the destruction of natural silica sand resources, relieve the pressure of silica sand mining, and is conducive to the ecological balance of natural sand resources.
Summary
When casting factories select Fused ceramic sand or sintered ceramsite in practical application, the molding sand process can be selected according to the physical parameters and casting characteristics of the above two kinds of artificial sand. Fused ceramic sand has strong adaptability and can be applied under any conditions. It is better to select fused ceramic sand for large steel castings, thick wall hot spot castings and stainless steel castings, because the burning point temperature of fused ceramic sand is high.
Fused ceramic sand has outstanding rapid cooling effect. If the production of wear-resistant steel castings such as high manganese steel, high chromium iron, low alloy steel etc. is aimed at refining the grain, fused ceramic sand can be selected. For example, fused ceramic sand can also be used to improve the mechanical properties of steel by rapid cooling in the production of engineering machinery steel castings. The rapid cooling effect and sintering temperature of sintered ceramsite are relatively weaker than those of fused ceramic sand and chromite sand, and the effect may be worse when used in thick hot spots, but the effect should also be good when used in small and medium steel castings and iron castings or wet mold sand, coated shell sand, etc.