Common unshaped refractory materials can be divided into castables, plastics, ramming materials, gunning materials, projection materials and coatings according to construction methods and material properties.

Castable is a kind of granular and powdery materials made of refractory materials, and a certain amount of binder and moisture are added together. It has high fluidity, is suitable for construction by casting method, and is a common unshaped refractory that can be hardened without heating. It is composed of refractory aggregate, powder, binder, admixture, water or other liquid materials. Generally, it is formed by pouring, shaking or tamping at the use site, and it can also be used as a preform.

Refractory castable is currently the most widely produced and used unshaped refractory material. Mainly used to construct various heating furnace linings and other integral structures. Certain high-quality varieties can also be used in smelting furnaces. For example, aluminate cement refractory castables can be widely used in various heating furnaces and other thermal equipment without slag and acid and alkali corrosion. In the parts that are corroded by molten iron, molten steel and molten slag and have high working temperature, such as tapping trough, ladle, blast furnace body, tapping trough, etc., a combination of low calcium and pure high alumina cement can be used. Refractory castable made of high-quality granular and powdery materials with high alumina content and good sintering.

For another example, phosphate refractory castables can be widely used in heating furnaces and soaking furnaces for heating metals, as well as coke ovens and cement kilns that directly contact materials. In some parts of metallurgical furnaces and other vessels that are in direct contact with slag and molten metal, repairing with high-quality phosphate refractory castables also has a good effect.

As the ratio of monolithic refractories in refractory materials increases, refractory castables will develop rapidly. At the same time, the variety will increase and the quality will increase accordingly. The focus will still be on the development of low cement, ultra-low cement and non-cement refractory castables. Combining resource conditions, select homogenized and high-quality raw materials and special aggregates to improve the basic composition, research and promote the use of fiber-reinforced refractory castables and self-flowing refractory castables, and apply various additives to improve the performance of refractory castables.