What is castable refractory mass and what are its types?

Introduction In the term refractories, “refractory mass” or “refractory mass” means materials such as clays and powders of refractory materials that have a high resistance to heat. For this reason, these materials are usually used in making parts such as refractory bricks, which are used in the lining of furnaces. Pourable refractory mass is one of these refractories that we will introduce in this article.

But what do we mean by refractory mass?

Pourable refractory masses are a combination of refractory materials and especially refractory cements. These materials are called “casting” because they must be poured into a mold to take their special shape.

The amount of water in the structure of these materials should be enough to easily pour and fill the mold.Therefore, it is expected that a relatively large percentage of water is used for their initial formation.

Alumina is one of the main components of castable refractory mass. The higher the percentage of alumina, the higher the refractory and mechanical resistance of the mass. Bauxite and chamotte are among the primary sources of alumina.

The most important types of castable refractory masses are:

Refractory concrete (alumina aggregates)
Carbon binding masses
Structural masses of chemical bonding

Refractory concrete

Refractory concrete is one of the main types of pouring refractories. These concretes can be porous or compact, and according to their chemical composition, they can be found with the following names:

Ordinary castable concrete (Regular Castable-RC)

Due to the presence of cement, these concretes have a hydraulic grip and do not need a lubricant.Deflocculated Castable-DC

In the production of these materials, a type of substance is usually used as a lubricant. Fluidized concrete can have different types based on the percentage of calcium oxide (CaO). In these materials, the lower the percentage of CaO, the less the amount of cement used in their construction, which makes their setting and hardening process more difficult. These concretes need to be heated to reach raw strength.

Compared to ordinary concrete, smoothed concrete has the following properties:

Less water percentage
Higher strength
Higher thermal conductivity
Greater apparent density and less porosity