Application of magnesia carbon brick in Converter Lining

Changxing Refractory is able to manufacture magnesia carbon brick for every ladle, EAF, and BOF. We will design you a well-balanced lining, providing optimal performance at the lowest possible cost. Our magnesia-carbon brick is made from more than 98% electrically fused magnesite, high purity graphite and metallic antioxidants as needed. Size and specification can be tailored according to furnace type. 

In the smelting process, the use of various parts of the converter conditions, damage is different, for different conditions of use of the various parts of the converter, the masonry refractories are not the same.
(1) furnace mouth: As the furnace temperature changes drastically, slag and high temperature exhaust scouring more powerful, and in the removal of scrap and feeding, the furnace was hit, so the furnace for the refractory material must have a high resistance Thermal shock resistance and slag resistance, to resistance to slag and high temperature exhaust scour, and not easy to hang steel and easy to clean.
(2) furnace cap: the furnace cap is the more serious parts of the slag corrosion, but also by the temperature changes, as well as the oxidation of carbon and dust, such as the role of scouring, so the need for strong slag resistance and thermal shock resistance magnesia carbon brick.
(3) Filling side: The splashing of slag and molten steel is easy to cause chemical erosion, abrasion, erosion, and charging on the charging side. It is also affected by the direct impact and erosion of scrap and molten iron Serious mechanical damage, so the requirements of MgO-C bricks in addition to a high slag resistance and a high high temperature strength, but also must have a very good thermal shock resistance, usually by adding antioxidant high-strength magnesia carbon brick.
(4) the steel side: the steel side of the basic damage from the mechanical damage when the thermal shock is also smaller, but by the tapping of molten steel when the thermal shock and erosion, damage faster than the loading side of the small When the same material as the charging side is used, in order to maintain the equilibrium life of the converter charge, we use masonry with a thickness in the form of a thin side.
(5) slag line parts: slag line is the long-term contact with the slag and slag corrosion serious parts, in the tapping side, with the slag position with the tapping time changes, and more obvious. In the slag side, due to the strong impact of the slag erosion and the other effects of the abdomen caused by the abdomen in the process of blowing, the damage is serious, so we need to masonry with good slag resistance of magnesia carbon refractory brick.
(6) trunnion on both sides: both sides of the trunnion in addition to the role of damage when blowing, the surface of the protective layer of the cover, not easy to repair, so the charge material in the carbon easily oxidized, and thus damaged, Excellent slag resistance, high oxidation resistance of high-grade magnesia carbon brick.
(7) hearth and bottom: these parts in the blowing by the severe scouring of molten steel, but compared with other parts of the damage to a more tired, the choice of low carbon content of magnesia carbon brick can also be used tar dolomite brick The When the high-speed blowing and the pool is too shallow, the bottom of the furnace site damage may be serious. In addition, when the use of bottom blowing, these parts of the damage may increase, should be used and the furnace side of the same material.

What are the processes for the preparation of magnesium carbon brick

Changxing Refractory is able to manufacture magnesia carbon brick for every ladle, EAF, and BOF. We will design you a well-balanced lining, providing optimal performance at the lowest possible cost. Our magnesia-carbon brick is made from more than 98% electrically fused magnesite, high purity graphite and metallic antioxidants as needed. Size and specification can be tailored according to furnace type.

Magnesium carbon brick is a high melting point of basic oxide oxide (melting point 2800 ℃) and difficult to be slag invasion of high melting point carbon material as raw material, add a variety of non-oxide additives. With carbonaceous binder combination of non-burning carbon composite refractory.

The traditional magnesia carbon brick produced by the synthetic tar binder in the cold mixing process is hardened during the process of tar damage and the necessary strength is obtained, thus forming isotropic glassy carbon. The carbon does not exhibit thermoplasticity, and the thermoplastic properties are eliminated in a large amount of stress during lining or during operation. The bituminous carbon brick produced by the asphalt binder has a high high temperature plasticity due to the formation of anisotropic graphitized coke during the asphalt carbonization process.

Therefore, the use of asphalt combined with the brick crack resistance is higher than the asphalt bonded brick. However, one of the disadvantages of bitumen-bonded bricks is the need for thermal mixing during the production and the provision of a brick mold preheating device. In this paper, the method of making MgO-C bricks  by cold mixing process is described. The resulting bricks have a lower modulus of elasticity so that they act to eliminate stress during operation. Ordinary coal tar pitch is harmful to environmental protection because of the presence of benzophen. The choice of benzene and low content of the special meet the environmental requirements of the binding agent.

In order to improve its oxidation resistance, can be added in the ingredients such as Si powder, Al powder, SiC powder or ferrosilicon powder additives, resin as a binder, high pressure molding, after 200 ~ 300 ℃ treatment can be used without Calcined. Mainly used for large-scale converter and ultra-high power furnace steel lining and furnace refining furnace lining and so on.

With the increase of carbon content, the bulk density and compressive strength of the magnesia-carbon brick are reduced. When the carbon content is between 6% and 8%, the high temperature flexural strength, thermal shock resistance, slag resistance and oxidation resistance of the magnesium carbon brick are good The carbon content is low and the slag resistance of the magnesia carbon bricks manufacturers is reduced. When the carbon content is 14%, the oxidation resistance of the magnesium carbon brick is the worst.

Magnesia brick thermal stability and strong points in China

Magnesia carbon brick series used for the electric furnace are made by adoption of fused magnetite, high-purity magnesium sand and graphite as principal raw material, through high-pressure molding and low-temperature treatment. This product is mainly used for electric furnace lining, which enjoys advantages including high temperature resistance strength, corrosion and spalling resistance. According to the smelting conditions and the kind of smelting steel, different brands magnesia carbon bricks are available. Magnesia-carbon bricks are resin bonded bricks containing high-purity fused and or sintered magnesia and flake graphite as their main ingredients.

Advantages of fired magnesia chrome bricks:
Chrome ore and magnesia carbon brick magnesite-chrome brick mill Compact fitted after a total production of fine powder, coarse granule combined with brick and magnesite, are effective measures to eliminate loose effect. In this way made of magnesia-chrome brick, compared with ordinary magnesia-chrome brick, bricks of low porosity and compressive strength, refractories and bending strength are higher. With the chrome ore and magnesia carbon bricks properties powder compact, high temperatures, calcination of magnesite-chrome brick made of synthetic magnesia-chrome sand, slag resistance and high temperature strength than other magnesite-chrome brick good.

Poor thermal stability of mgo brick supplier:
Magnesia brick can only take water-2-3. Expanded the most magnesia bricks in refractory, low coefficient of linear expansion. So when the magnesia brick oven, you want to have plenty of expansion joints. dration of magnesia brick: magnesia brick prolonged under wet condition can slowly drate, magnesia brick strength greatly reduced, so you must pay firebrick refractory sale attention to moisture when stored magnesia brick.

Henan Xinmi Changxing Refractory material Co., Ltd. our product portfolio covers shaped products such as refractory material, refractory brick, refractory castable, refractory nozzle, ceramic fiber,slide gate, etc;