Three common kinds of refractory castable

Refractory castable is monolithic refractories that widely produced and used currently. Mainly used for the construction of various heating furnace lining and so on overall structures. Some high quality varieties can also be used for smelting furnace.

Such as aluminates cement castable can be widely used for various heating furnace and other no residue, no corrosion of thermal equipment, and is the main varieties of refractory castable unshaped refractory materials, according to the different of the cementing material, curing and molding mechanism can be divided into three that hydraulic, air hardening and fire hard.

1. Hydraulic refractory castable: Using cement as the cementing material pouring in the hardening process require water to take part in a chemical reaction, forming a gel hardening strength, are hydraulic refractory castable. Cement is to determine the strength of castable (especially the atmospheric temperature strength) of the main factors, but its refractory degree is relatively low, so in that room temperature strength necessary, should as far as possible to reduce the amount of cement. If in order to compactness and construction workability, can be appropriate to increase the refractory powder. Reduce the amount of cement is also one of the measures to reduce the cost of. The construction should be strictly prevent aluminate cement and Portland cement, lime mixture. Because these two kinds of different chemical composition of the mixture will produce water aluminum acid calcium three, which greatly reduced strength.
   
2. Air hardening castable: Refers to the cementing agent in the maintenance of the absorption of CO2 in the air gradually solidified hardening. Refractory castable is the most commonly used water glass refractory concrete. Water glass refractory castable besides the performance of high-temperature resistance, it is acid resistant, abrasion performance, so often used as chemical equipment lining. Water glass, refractory castable process hardening under natural conditions is very slow, need to add coagulant in the construction (sodium fluorosilicate, high alumina cement).
3. Fire refractory castable: Using phosphoric acid and phosphate castable binder, need to pass through the heating and baking to obtain the strength and high temperature performance, so that the fire refractory castable.