Basic / Magnesite Bricks

Magnesite bricks are basic refractory bricks with 80 to 92% MgO, used in steel-melting furnaces (EAF and BOF), cement rotary kilns and lime kilns. They are called basic because their chemistry resists attack by basic slags, such as those in steelmaking and clinker production. Chrome-magnesite variants containing Cr2O3 are available where extra strength is required.

Magnesite bricks have a maximum service temperature of 1700°C to 2000°C, with good hot strength at very high temperatures. This places them among the highest-temperature refractories in this catalogue. In practice the service limit also depends on slag chemistry, atmosphere and thermal cycling, so the grade is chosen for the specific furnace zone.

Magnesite bricks are made mainly of MgO at 80 to 92%, while chrome-magnesite bricks also contain Cr2O3 for extra strength. Both are basic refractories for steel and cement applications. The choice depends on the furnace zone, slag conditions and any local rules on chrome-bearing materials, so state your application and preference in the enquiry.

Choose Basic / Magnesite Bricks where the lining faces basic slags, as in steel-melting furnaces and cement kilns, and High Alumina Bricks where slags are neutral to acidic or conditions are less severe. Magnesite serves up to 1700°C to 2000°C, while high alumina serves up to 1500°C to 1750°C. Matching refractory chemistry to slag chemistry is the main selection rule.

Magnesite bricks have a bulk density of 2.8 to 3.1 g/cm³, cold crushing strength of 350 to 600 kg/cm² and apparent porosity of 14 to 20%. The high density and relatively low porosity limit slag penetration. They are supplied in the standard 230 x 114 x 75 mm size, and custom shapes are available for kilns and furnaces.

Yes, magnesite bricks must be stored dry and under cover, because magnesia can react with moisture and damage the brick before use. They should not be laid in direct contact with acidic refractories such as silica bricks at high temperature. Use a compatible basic mortar, follow the kiln or furnace supplier's joint and expansion design, and heat the new lining up gradually.

Magnesite bricks in this catalogue are referenced to ASTM C455. The main selection points are MgO content, density, cold crushing strength and service temperature, listed in the technical data table. If your specification calls for a particular MgO level or class, tell us in your enquiry and we will confirm what is available for your order.

Magnesite bricks are exported from India under HS code 69021010, refractory bricks and shapes of magnesite. Heading 6902 covers refractory bricks, blocks and tiles, and subheading 690210 applies where magnesium, calcium or chromium oxides dominate. Import duties and final national digits are set by your country, so confirm the classification with your customs broker.

Magnesite bricks are packed on wooden pallets and shrink-wrapped, which gives a barrier against moisture during sea transit and port storage. On arrival they should be moved into dry, covered storage and kept wrapped until use. For kiln relines, send the shape schedule and quantities per shape with your enquiry, as custom shapes are quoted individually.