Refractory gunning material is a material constructed by spraying. The refractory gunning material uses compressed air or mechanical pressure in the pipeline to obtain sufficient pressure and flow rate, and is sprayed through the nozzle onto the sprayed surface to form a strong spray layer.

The spraying methods of refractory gunning materials are divided into three categories: wet method, dry method and flame method.

(1) Wet spraying. Wet spraying refers to the refractory gunning material added with water or liquid binder, and then sprayed onto the sprayed surface. Wet spraying methods are divided into four categories: mud method, wet method, semi-dry method and false dry method. The latter three methods are suitable for building furnaces or repairing furnace linings.

The mud method is to stir the refractory mixture into slurry first and then spray it.The mud method is mainly used for hot gunning furnace lining repair; the wet method is to stir the refractory mixture into pumped mud and then spray it; the semi-dry method is to mix the refractory mixture first, add a small amount of water to the material and stir it evenly. When it is transported to the nozzle, add the remaining water before spraying; the false dry method is to stir the refractory mixture evenly through the mixer, then transport it to the nozzle and add water before spraying.

(2) Dry spraying. Dry spraying refers to spraying the mixed refractory gunning material directly onto the sprayed surface through a nozzle, and is mainly used for repairing furnaces.

(3) Flame spraying. In flame spraying, the mixed refractory gunning material is transported to the nozzle by high-speed flowing oxygen in the pipeline, and then ejected together with the combustible gas. The material is ejected during combustion and is sprayed onto the sprayed surface in a molten state. This method is mainly used to repair furnace linings with thermal spraying. It does not damage the original furnace lining. The sprayed coating is easy to sinter and has a long service life.