Current Overview of Fused Ceramic Sand
The enthusiasm for investment in fused ceramic sand continues to rise in the market, and the number of new fused ceramic sand manufacturers is increasing. There are more than 20 Fused ceramic sand manufacturers with wide distribution and incomplete statistics. There are manufacturers in Henan, Hebei, Shanxi, Inner Mongolia, Liaoning and other provinces and regions, with an annual production capacity of more than 200,000 tons. Export sales volume of fused ceramic sand keeps growing, and annual export volume of which is more than 30,000 tons. More and more foundries realize the application advantages of fused ceramic sand and become the choice of expanded, reconstructed and newly built foundries. Production and application of Fused ceramic sand is in a long ascending path.
Application of Fused Ceramic Sand
Fused ceramic sand is applicable to various casting methods; For example: sand casting (clay sand, resin sand, water glass sand), V method, loss mold, investment mold precision casting, etc. It is applicable to the casting production of various binders and metal materials. It can not only greatly improve the casting quality, but also easy to clean the sand. The sand preparation process has no big difference with silica sand. For most castings, the coating can be omitted or the amount of coating can be reduced, especially for the castings with high quality requirements. The following figure shows the application process distribution of Luoyang Kailin Casting Material Co., Ltd. according to the actual application of customers.
What is the impact of main technical indexes of Fused ceramic sand on casting quality?
1. Influence of Al2O3 content on casting quality
The content of Al2O3 directly determines the refractoriness and sintering point of ceramic sand. The higher the content is, the higher the refractoriness and sintering point are. The Al2O3 content of the bead sand used in the production of castings of different materials is also different. For steel castings, the pouring temperature is generally higher than 1550 ℃, and the perlite with Al2O3 content more than 73% is generally selected; On the contrary, the casting will be subject to sand adhesion due to low fire resistance and sand melting. Casting temperature of iron casting is about 1400 ℃, and the content of Al2O3 can be 67% - 70%. For extra large iron casting, refer to the index of perlite for steel casting.
In addition, the content of Al2O3 also affects the crushing rate and durability of the pearl sand. When multiple strong regeneration is required, the pearl sand with higher content of Al2O3 shall be selected.
2. Influence of clay content of casting pearl sand on casting quality
If the silt content of casting perlite exceeds the standard, the silt content will reduce the refractoriness and burning point of perlite and the air permeability of type (core) sand. Especially for resin sand with high mud content, the strength of type (core) sand will be greatly reduced, the addition amount of resin binder will be increased, and the gas generation amount of resin sand will be increased. Strength, air permeability and air emission all seriously affect the quality of castings.
3. Influence of average fineness and grain size composition of casting pearl sand on casting quality
The average fineness and grain size composition of perlite are important parameters related to the surface roughness of castings. Generally speaking, the finer the sand is, the smoother the casting surface will be. Meanwhile, the greater the demand for binder is, the greater the air generation is. This is the common property of all casting sands. The selection of suitable grain size is important to ensure the yield and surface finish of castings and needs to be determined based on adequate testing or reference to existing successful experience.