Refractory for electric arc furnace lid

EAF uses A1203 65% -85% alumina brick masonry lid, the special needs of the site is also used tabular alumina brick (with a plate Al20390% -100%), but the price is expensive, silica brick is about 10 times higher 31V or thermal stress relief lid damaging effects of aluminum bricks, high alumina brick firing using phosphate bonded alumina bricks do not burn with white masonry made good use of effects. Some (HP) in high power electric furnace cover, the main use of high alumina bricks (about 80% Al2 03) and chemically bonded magnesia-chrome brick (Mg0> 65%, Cr2 037% _15%) Consolidated masonry furnace cover. High power (UHP) electric cover using mullite corundum brick, the brick main feature is a good thermal stability, resistance to high temperature load-deformation ability, it just to meet the requirements of the lid refractories, MK-80, No. MO corundum bricks,

is fused corundum and fused mullite particles strengthen the structure of products. 50t UHP EAF for cover, stainless steel and bearing steel smelting life increased by 25% -35% higher than magnesia-chrome brick roof.

High alumina brick lid. Alumina brick masonry furnace lid began in the late 1950s. At that time the use of high alumina brick lid (Ak 0365% -80%) increased by 4 times higher than silica brick lid life. Firing alumina bricks (A \ 2 03 80 16) and phosphate binding does not burn alumina brick (Al2 03 80% -85%) and mullite brick firing or not firing phosphate binding mullite brick, they have in common is an excellent thermal shock resistance. The life of the early 1960s, the lid has reached about 200 furnaces.

Refractory industry developing trends——Cyanite

Future high-purity refractory materials will be the main and synthetic natural selection and use. Development and utilization of the "three stone" raw materials, namely andalusite, sillimanite, kyanite raw materials, can improve the microstructure and thermal properties LAS refractories.

As the "three stone" at high temperatures into the lower phase mullite and mullite expansion coefficient is small, help to improve the thermal shock resistance of the material. Andalusite in the material can be added with countless subtle diffusion thermal stress becomes void formation, making the stress to be released within the refractory, thus improving the thermal shock resistance. And sillimanite completely mullitization the temperature is higher, will help improve the high-temperature creep resistance. In addition, due to the volume expansion effect produced mullitization also accompanied by high temperature creep favorable. Development of high-quality synthetic refractory raw materials, the amount of developed countries in the use of natural raw materials reduced and the amount of high-purity synthetic raw materials is increasing, the reason is the extensive use of synthetic materials proportion of unshaped refractory materials is increasing, and the extensive use of natural raw clay brick, high alumina brick, zircon brick production is declining.

Therefore, innovation, research and development, education, management and investment, will be the key to maintaining the vitality of future refractory industry and success. Current and future years for Chinese refractories industry, is an experienced structural optimization, corporate restructuring and product structure adjustment period. China's strategy of development should be based on Chinese refractories rich natural resources, based on the development of high-performance synthetic materials and more high-performance, functional products to meet the advanced requirements of high temperature industrial development and a focus on clean steel casting and production. At the same time, you should pay attention to equipment and management, improve product quality refractory materials and the stability and reliability.