Brief introduction of low cement castable refractory material

Low cement castable refers to a castable with a lower amount of cement. The cement dosage of refractory cement castables is generally 15% to 20%, and the cement dosage of low cement castables is about 5%, and some even reduce to 1% to 2%. The purpose of reducing the amount of cement is to improve the fire resistance of the castable.

Low cement castables rely on the addition of several special raw materials to obtain good performance: First, pure calcium aluminate cement, due to the high content of effective mineral CaO·Al2O3, can obtain the required strength with less mixing. The second silica fume is glass beads with an SiO2 content between 93% and 98% and an average particle size of about 0.5μm. After adding silica fume, the castable has good fluidity, low water requirement for molding, and low sintering temperature, which improves the performance after heat treatment. Third, alumina powder is easier to participate in the reaction and improve the fire resistance of the material. Fourth, the water reducing agent, which can be adsorbed on the surface of the powder, and then generate electrostatic repulsion to disperse the powder, so as to further play the role of fine powder.

Advantages of integral casting of low cement castables

Low-cement castable is a high-tech refractory developed on common castables by using rheological principles, the tightest packing theory and ultra-fine powder technology. It has the characteristics of low porosity, small pore size, high density, good volume stability, high strength and small water addition, and it overcomes the characteristics of a significant drop in strength of ordinary castables at 800~1200℃, and increases with temperature And increase, so that the thermal shock of the furnace body can be more than doubled.