Refractory for heat treatment furnace

The heat treatment furnace here mainly refers to the heating metal to improve the performance of the structure of the thermal equipment. Various heat treatment processes include annealing, normalizing, tempering, carburizing and nitriding, etc. They use basically the same heat treatment furnace.

The use temperature of heat treatment furnace is generally lower than that of soaking pit and heating furnace, generally in 500~1000℃, no chemical erosion, because of temperature fluctuation and easy to produce thermal shock, so when choosing refractory material, should consider thermal shock resistance index. But the common clay brick, high aluminum brick, light insulation clay brick and high aluminum brick have better results. Cordierite brick, silicon carbide brick and corundum brick are used for certain places with rapid temperature change, such as furnace door. For heat treatment furnace, heat preservation and energy saving is the top priority, which plays a very important role in reducing costs. Therefore, in recent years, lightweight refractory materials and refractory fibers and other thermal insulation refractory materials have been widely used, especially the proportion of refractory fiber products with very good thermal insulation effect is increasing. In recent years, there are more and more heat treatment furnaces using castable, and their service life has reached more than 3 years, which is significantly better than brick lining.

The furnace type of heating furnace is a lot of, press operation mode to divide into commonly intermittently type and continuous type. The use temperature of heat treatment furnace is generally lower than that of soaking pit and heating furnace, without chemical erosion, as a result of temperature fluctuation and easy to produce thermal shock, so in the selection of refractory, should consider thermal shock index. However, general furnace lining using common clay brick, high aluminum brick and light insulation clay brick and high road turn have better results. Cordierite brick, silicon carbide brick and corundum brick are used for certain places with rapid temperature change, such as furnace door. In order to improve the thermal insulation effect, in recent years, the traditional light refractory brick is generally replaced by refractory fiber.