Heavy spray paint JYG-1650

Refractory spray coatings and repair materials are a kind of material that has developed rapidly in the past ten years, and are also an important type of refractory in unshaped refractories. Its output is only lower than refractory castables. In kilns and thermal equipment, the material can be used for spraying new linings, and can also be used for repairing furnace linings. Production practice has proved that this type of material is an effective technical measure to speed up the construction progress, shorten the repair time, extend the service life of the furnace and reduce the consumption of refractory materials. It is a promising material with good development prospects and is generally valued at home and abroad.

According to Henan refractory brick experts, the refractory spray coating is sprayed with a spray gun to spray the refractory mixture onto the sprayed surface, that is, the material applied by spraying method is called the refractory spray coating. Spraying is carried out by spraying machine or spray gun, which is a new process in furnace building and repairing. The refractory spray paint is used in the pipeline to obtain a sufficient age speed with the help of compressed air or pillow mechanical pressure, and is shot through the nozzle to the sprayed surface to form a firm spray layer. The spraying methods are divided into three types: wet method, dry method and flame method; according to the state of receiving materials on the sprayed surface, it is divided into cold material spraying method and molten material spraying method.

Wet spraying refers to the refractory spray paint sprayed onto the sprayed surface after adding water or liquid binder. According to the order of adding water or liquid binder and its dosage, it is divided into four types: mud method, wet method, semi-dry method and pseudo-dry method. Among them, every two methods are mixed and used, it is called a hybrid method. The mud method is to mix the refractory mixture into a slurry before spraying, and is mainly used for thermal gunning of the furnace lining; the wet method is to stir the refractory mixture into a pumped mud before spraying (see Chapter 9); the semi-dry method is First, add a small amount of water to the refractory mixture and stir it to evenly wet it, and then transfer it to the nozzle and add the remaining water before spraying; the false dry method is to mix the refractory mixture through a mixer and then transport it to the nozzle to add water and spray. The latter three methods are suitable for spraying furnace construction or gunning furnace lining.

Dry spraying means that the mixed refractory spray paint is sprayed directly onto the sprayed surface through a nozzle, which is mainly used to repair the furnace.

Flame spraying is to use oxygen to transport the mixed refractory spray paint to the nozzle where it meets the combustible gas and spray it together. The combustible gas burns, and the material travels in the flame and melts into a plastic state and shoots onto the sprayed surface. This method is mainly used for thermal gunning furnace lining, with less damage to the original lining, easy sintering of the sprayed layer, long service life, but high cost. In addition, using a plasma gun to melt or semi-melt the refractory mixture and spray it onto the sprayed surface and spray the molten slag in the furnace with an appropriately adjusted composition onto the lining (namely, the slag splashing method), which also belongs to this category method.

Refractory repair materials refer to materials used to repair kilns and thermal equipment, and are generally referred to as refractory repair materials. The material is actually classified by use. The construction methods include spraying, filling, pressing, pumping or grouting, etc. There are many types of refractory repair materials, mainly including refractory gunning materials, spray gunning materials, refractory injection materials, refractory press-in materials, refractory pump injection materials and refractory grouting materials. This material uses spraying methods to construct more, so this chapter is not included, and only important varieties are introduced. The refractory repair material has excellent performance and convenient use, can improve the service life of the kiln, increase the output, reduce the cost, and the economic benefit is significant. Therefore, in recent years, the development of refractory repair materials has been rapid, and its output far exceeds that of refractory spray coatings. In refractory spray coatings and refractory repair materials, many materials are universal, but the method of traveling workers is different, and the title is also different. For example, mud spray paint and refractory grouting material, refractory gunning material and dosing material, etc., have basically the same composition and performance, but the construction method is different, and the title is also different.

The material composition of refractory spray coatings and refractory repairing materials is basically similar to refractory castables of the same type. The difference is that the critical particle size of refractory aggregates is smaller, generally 3~5. nm, the combined dosage of refractory powder, superfine powder and binder is more, generally 35%-45%. Due to the similar material composition, the setting and hardening mechanism of this type of material and the physical and chemical changes under high temperature are basically the same.

The key technology of refractory spray coatings and refractory repair materials is mainly adhesion, adhesion, strength and sintering. This is also the basic characteristic that the material should have, otherwise the service life of the spray coating and repair layer will be reduced. This characteristic is closely related to the material itself, and more importantly, it is restricted by the sprayer and other machinery and construction process parameters, and is also affected by factors such as the state of the spray body and the conditions of use. These constraints and influencing factors are the basis for choosing refractory spray coatings and refractory repair materials, as well as the key link to obtain a good spray or repair layer. Therefore, it should be rationally selected, carefully adjusted, and strictly controlled.

The scope of application of refractory spray coatings and refractory repairing materials mainly includes blast furnaces, hot blast furnaces and tapping troughs, open hearth furnaces, converters and electric furnaces, ladle and secondary refining furnaces, heating furnaces and soaking furnaces, tube heating furnaces, converters, Boiler, flue and chimney, etc. Both spraying and repairing the furnace lining have achieved good results.