The Production Process of Magnesia Carbon Brick

October 15, 2018

The production process of magnesia carbon brick

Magnesia carbon bricks mainly use fused magnesia, high carbon graphite as the main raw material, adding appropriate amount of antioxidants, and thermosetting phenolic resin as a binder to be formed by high pressure molding. Magnesia carbon bricks are mainly used in converters, AC arc furnaces, linings of DC arc furnaces, slag lines of ladle, and the like.

1. Selection of magnesia carbon brick

In order to maintain the overall uniformity of the thermal expansion of the particles and the matrix portion of the MgO-C brick, the matrix portion needs to be mixed with a certain amount of fine powder of magnesia, and also the structure maintains a certain integrity after partial oxidation of the matrix.

2. Magnesium carbon brick ingredient

The amount of graphite added should be considered in combination with different bricks and different parts of the brick. The melting loss of MgO-C bricks is governed by the oxidation of graphite ink and the dissolution of MgO into the slag. Increasing the graphite can reduce the erosion rate of slag, but it increases the oxidation of gas phase and liquid phase. Damaged.

3. Mixing of magnesia carbon brick

The graphite is light in density and tends to float on top of the mix during mixing, making it incompletely in contact with other components in the furnish. High speed mixers or planetary mixers are generally used.

The order of addition is: magnesia particles (crude, medium) → graphite → binder → mixed powder of magnesia powder and additives.

4. Molding of magnesia carbon brick

The forming process begins with the selection of a suitable tonnage press. Accurately control the weight of the mud during molding to ensure uniformity, and the number of hits and the weight must meet the requirements.

Molding is an important way to increase the packing density and densify the structure of the product. Therefore, high-pressure molding is required, and the pressing is strictly in accordance with the operating procedures of light weight, heavy weight and multiple pressurization.

5. Heat treatment of magnesia carbon brick

Magnesia carbon bricks do not require high temperature firing, but heat treatment is required. After baking for 24 hours in an environment of 150-200 ° C, the material and the bonding agent are solidified to make the strength of the product meet the requirements.