Hot Blast Furnace Refractory Spray Coating

The technical characteristics of the refractory spray paint:

The fire-resistant spray coating is constructed with the spraying method. The material mix ratio, the spraying operation, the rebound rate and the dressing process are as follows. The mixture ratio of spray coating should meet the following requirements: to achieve the required strength, less springback, less spray dust, good adhesion and no blockage of the pipeline. When the cement binder is used for dry or semi dry spraying, the amount of cement is about 20% ~ 25% of the total material. When the cement is too much, the amount of dust increases when the spray is sprayed, and the shrinkage of the spray coating increases after the hardening.

 

Although lining of blast furnace and hot blast furnace is a very mature process and construction, some details still need to be paid attention to. Spray coating lining is a very important process for blast furnace and hot blast furnace. Spray coating construction is the guarantee of furnace body sealing and thermal insulation performance. Spray coating construction is a highly continuous operation. During construction, attention must be paid to the material conveying distance, construction height, especially wind pressure and water addition.

When spraying the paint, first check whether the anchor is welded firmly. The size and spacing distribution of the anchors are very important considerations. If the paint is too dense, it will easily crack, and if it is too thin, the strength will be poor.

Before spraying the paint, you should carefully read the spraying and water adding instructions given by the manufacturer, and then conduct a trial spraying. Only after the spraying is qualified can the formal spraying construction be carried out.

The spraying process is to mix the spray material evenly, then put it into the sprayer, and the sprayer will supply air and material. After the construction area is cleaned and wetted with water, spraying can begin.

The spraying sequence is air supply → water supply → material supply, and the sequence is reversed when the spraying is stopped. The straight section is sprayed from top to bottom and from left to right, and the spray gun moves gradually downward in a circular cycle along the circumferential direction. The spraying thickness is 40 to 50 mm. For thickness exceeding 50 mm, spraying must be performed twice or more. When spraying the arch top, spray from bottom to top in a circular motion.

It is best to place the spray gun vertically at a distance of 1.0 to 1.2 meters from the construction surface, and adjust the wind pressure and water pressure continuously according to the on-site conditions. The spraying of the upper and lower layers of spray paint should be completed within the initial setting time.

The expansion joints of the spray material layer are reserved at the joints of each section or grid. If spraying is intermittent, the spray material layer at the interruption must be roughened when spraying again, and the interruption must be moistened with water before spraying construction.

After spraying the paint in each area, it is necessary to carry out leveling treatment, first make rough repairs and then make the concave surface flat, and then use tools to scrape it finely.

Hot Tags: hot blast furnace refractory spray coating, China hot blast furnace refractory spray coating manufacturers, suppliers, factory, Self-flowing Castable, Refractory Ramming Mass, Refractory Repair Material, Self-flowing Castables, Hot Blast Furnace Refractory Spray Coating, Silicon Carbide Ramming Mass