Magnesia chrome bricks are very common in industrial kiln use and are in demand in the steel and non-ferrous industries. As a company specializing in the production of refractory materials, Kerui Refractory has been producing magnesia chrome bricks for more than 20 years and is worthy of your trust.
The raw materials for manufacturing magnesia chrome refractory are magnesia and chromite, and the main minerals are periclase and spinel. This type of high temperature fire brick has high refractory resistance, high high-temperature strength, strong resistance to alkaline slag erosion, excellent thermal stability（Wikipedia）, and certain adaptability to acidic slag. What’s more, the purity of magnesia raw materials should be as high as possible. The requirements for the chemical composition of chromite are: Cr2O3: 30~45%, CaO: ≤1.0~1.5%.
Generally speaking, in practical applications, we need to make a reasonable configuration of refractory fire bricks specification based on the kiln structure and working environment. The working principles of industrial kilns are different, and the types of magnesia-chromium bricks used are also different, so Kerui has produced various types of magnesia-chromium bricks for everyone to choose from. In addition to magnesia-chromium bricks, copper metallurgical hot kilns also use magnesia-chromium amorphous refractory materials such as magnesia-chromium ramming materials, magnesia fillers, and magnesia-chromium castables. If you want to buy refractory bricks, please contact Kerui.
Magnesia chrome bricks are generally divided into two types: unburnt mag chrome bricks and burnt mag chrome bricks. Burnt mag chrome bricks also have three types, they are common burnt mag chrome bricks, direct bonded mag chrome bricks and fused rebonded mag chrome bricks.
Unburnt magnesia chrome bricks are made of high-quality magnesia and chromium ore, polyphosphate as the binding agent, and are made by high-pressure molding and low-temperature heat treatment. Compared with burnt magnesite chrome bricks, these wholesale fire bricks have a simplified manufacturing process and low cost. It also has high normal temperature compressive strength, low porosity and good thermal shock stability.
The polyphosphate chemical binder will completely decompose at about 1000℃. At this temperature, the medium and high-temperature structural strength of unburned mag chrome bricks is low. Therefore, the use effect is better in the firing zone of wet rotary kilns with frequent kiln shutdowns and low operating rates.
Generally, refractory bricks manufacturers produce four types of burned magnesia chrome bricks for everyone to choose from. They are common burnt magnesia chrome bricks, direct bonded magnesia chrome bricks, fused semi-rebonded magnesia chrome bricks and fused rebonded magnesia chrome bricks.
Common Burnt Magnesia Chrome Bricks
Common burnt mag chrome bricks are made of high-quality magnesia and chromium ore. The Cr2O3 content can be adjusted according to different needs, and the product has good thermal stability and high-temperature performance.
It is widely used in cement kilns, nonferrous metallurgical furnaces, etc.
Direct bonded mag chrome bricks use chrome ore with low impurity content and high-quality high-purity mag as raw materials. It is formed by high pressure and fired at a high temperature of over 1,700℃. Therefore, these magnesia refractory bricks have good high-temperature performance, strong resistance to slag erosion, and resistance to cement clinker erosion.
The main applied working parts are: the bottom of the top-blown converter and the non-working layer of the furnace wall, the furnace wall of the Kifset furnace, the furnace wall of the Ausmet furnace, and the furnace top and furnace wall of the reverberatory furnace.
Fused rebonded mag chrome bricks are made by melting the raw materials into fused mag chrome materials using the electric fusion method, then crushing them into a certain particle size, and finally mixing, shaping and sintering. This industrial fire brick has a fine-grained texture with evenly distributed pores and micro cracks and is more sensitive to sudden temperature changes than fused-cast bricks. In addition, the high-temperature performance of fused magnesia chrome bricks is between that of fused cast bricks and directly bonded bricks.
The main applied working parts are: the working layer of the top-blown converter furnace, the furnace mouth of the horizontal converter, the furnace mouth of the anode furnace, the furnace mouth of the electric furnace, the working layer at the bottom of the Kifset furnace, and the furnace wall of the Ausmet furnace and the bottom of the furnace and the lower part of the oxygen-rich bottom-blown slag line and the eye area.
The main crystal of mag chrome bricks is strongly alkaline periclase. Periclase has high density, low moisture, high molding pressure, low apparent porosity and high volume density. Therefore, these high performance magnesite bricks have the characteristics of the multi-mineral composition, strong alkalinity and high density.
Please refer to the table below to select the type of mag chrome brick you want. If you are not sure about the model of mag chrome bricks you want to buy, please contact Kerui, and Kerui’s business manager will help you find suitable magnesia chrome brick for sale.
| Item/Grade | MGe-16A | MGe-16B | MGe-12A | MGe-12B | MGe-8A | MGe-8B | |
|---|---|---|---|---|---|---|---|
| ω (MgO)/% | μ0 ≥ | 50 | 45 | 60 | 55 | 65 | 60 |
| ở | 2.5 | ||||||
| ω (Cr2O3)/% | μ0 ≥ | 16 | 16 | 12 | 12 | 8 | 8 |
| ở | 1.5 | ||||||
| Apparent Porosity/% | μ0 ≤ | 19 | 22 | 19 | 21 | 19 | 21 |
| ở | 1.5 | ||||||
| Cold Crushing Strength/MPa | μ0 ≥ | 35 | 25 | 35 | 30 | 35 | 30 |
| Xmin | 30 | 20 | 30 | 25 | 30 | 25 | |
| ở | 15 | ||||||
| 0.2MPa Refractoriness Underload T0.6/℃ | μ0 ≥ | 1650 | 1550 | 1650 | 1550 | 1650 | 1530 |
| ở | 20 | ||||||
Refractory bricks provide people with safety in the industrial field. At the same time, some refractory brick properties may be partially damaged due to the influence of external conditions. Then we need to maintain and repair these refractory bricks. Generally, we know that the refractory bricks required for industrial kiln production are mainly mag chrome bricks. The following are the precautions for excavation and repair of mag chrome bricks.
If you are looking for a long-term and reliable magnesia chrome brick supplier, Kerui will be a good partner. We guarantee the quality of mag chrome bricks and have a complete pre-sales to after-sales service system. If you have questions about mag chrome bricks, please contact us on pinterest. We will reply to you within 24 hours.