Raw material and mixing
(1) The order of adding ingredients
Industrial alumina—clay—purified bauxite—kaolinite—polystyrene pellets—additives—water
(2) Mixing and mixing time
After the raw material of high-alumina heat-insulating refractory bricks are mixed according to the proportion, use a vertical, horizontal or forced mixer to dry mix them for 1 to 2 minutes to make the raw materials uniform, add admixtures and appropriate amount of water and continue to stir for 5 to 10 minutes. Then take out the mixed raw materials for molding;
Molding
The molding methods of high-alumina heat-insulating refractory bricks are generally divided into manual, vibration, casting and so on. The general molding method is casting method. The moisture content is controlled at 35~45%. The molding method is to pour the evenly stirred slurry into the prepared steel or aluminum mold, and stir properly in the mold while pouring, so that bubble occurs and the gas is basically eliminated. Then scrape its surface flat. After 4 hours of natural drying, the molds are put into the tunnel drying hole, dry for 72 hours, when the moisture is less than 3%, then enter the high temperature tunnel kiln to be fired.
Next issue we will continue to introduce production of high-alumina heat-insulating refractory fire brick.
