A Refractory Furnace is a type of high-temperature industrial or laboratory furnace that is specifically designed with refractory materials capable of withstanding extreme temperatures, typically ranging from 1200°C to over 2000°C, depending on the application. These furnaces are used to perform thermal processes such as melting, smelting, calcining, sintering, and heat treating of materials that require exceptional heat resistance.

The defining characteristic of a refractory furnace is the construction of its inner chamber (or lining) using refractory materials — heat-resistant ceramics or composite substances like alumina, silica, magnesia, fire bricks, or zirconia-based compounds. These materials provide insulation, structural strength, and chemical stability at extremely high temperatures.

Refractory furnaces are commonly used in metallurgy, ceramics, cement, glass, and power generation industries, where intense and continuous heat is essential. They can be powered by electricity, gas, oil, or even coal, depending on the process requirements.