Fused ceramic sand has the characteristics of spherical particle shape, low thermal expansion rate and high refractoriness. Fused ceramic sand was applied to the core making process of hot box coated sand. The results showed that by optimizing the ratio of Fused ceramic sand and high temperature resistant coated sand and the core making process parameters, the high temperature expansion rate of the core sand could be reduced, the bending strength and fire resistance of the core sand could be improved, and the core breaking rate of the cylinder head could be effectively reduced by eliminating the over-curing problem of the core sand.
The sand mold of cylinder head is easy to break
Cylinder head is one of the core components of diesel engine, and its working environment is bad, so it requires high performance and quality of its castings. At the same time, due to its complex internal structure, it is difficult to cast. There is a four valve cylinder head independently developed by our factory, with an outline size of 247 mmx156 mmx185 mm. It uses the ordinary high-temperature coated sand hot box core making process. Due to the large size difference, the thinnest part is ≤ 5 mm, and a large number of core breaking defects occur at the weakest part of the sand core size during core making, core repair, transportation and after pouring.
Using Fused Ceramic Sand to Solve the Problem of Sand Core Fracture
In order to solve this casting problem, according to the advantages of Fused ceramic sand, such as round shape, small coefficient of thermal expansion, high fire resistance, and good air permeability, Fused ceramic sand has been gradually applied to the core making process of cold box for cylinder block of complex aluminum alloy and gray cast iron of automobile engine. According to the differences and similarities of the cold and hot box core making process, the production process test of fused ceramic sand shooting hot core was carried out.
Fused Ceramic Sand Major Specification
1. Shape: Sphere
2. Angle Factor: ≤1.1, very spherical
3. Bulk Density: 1.95-2.05 (g/cm3)
4. Refractoriness: ≥1790℃
5. Thermal expansion: 0.13％ (10 minutes at 1000℃)