Castable is made by mixing refractory aggregate and powder as refractory raw materials, adding binder and additives. The binder commonly used for castable is aluminate cement.
The addition amount of cement can affect the service performance, high temperature strength and corrosion resistance of castable.
The refractory castable with aluminate cement as binder, the castable with cement content of 3-8% and CaO content of 1-3% is called low cement castable; Castable with CaO content of 1.0-2.5% can be called ultra-low cement castable.Low cement castable is a high-grade refractory castable. It is called low cement castable because of the low CaO content in cement.
Low Cement Castables Types
Low cement castable can be made into high aluminum low cement castable, corundum low cement castable, aluminum magnesium spinel low cement castable, etc. according to the selected refractory raw materials. According to the construction performance, it can be divided into self flowing low cement castable and vibrating low cement castable.
Low Cement Castable Characteristic
1) The low content of calcium oxide in castable can reduce the low eutectic phase in the material, so as to improve the fire resistance, high temperature strength and slag resistance;
2) The cement hydrate produced after molding and curing is less, and there is no problem that the medium temperature strength decreases due to the destruction of a large number of hydration bonds during heating and baking, but it is gradually sintered and the strength increases with the increase of heat treatment temperature;
3) The water demand of castable is greatly reduced, so the porosity is low and the bulk density is high;
4) By properly adjusting the strength composition of castable, it can be prepared into self flowing castable and pump pouring castable.
Low Cement Castable Application
Low cement castable is suitable for lining of heating furnace, various heat treatment furnaces, electric furnace covers, shaft kiln, rotary kiln, blast furnace taphole, ladle, molten iron ladle, etc;
