Furnace roof which may be refractory-lined or water-cooled, and can be shaped as a section of a sphere. The roof also supports the refractory delta in its center, through which one or more graphite electrodes enter.
Consists of big furnace roof, small-ramming roof; big furnace roof with charging hole is the water-cooled roof with concentric cylinder. Small furnace roof is ramming by refractory, there are three electrode holes on it. Inside the holes, where it sets water unheated barn. Pin is used for connected with big roof and small roof, thus it is convenient to change big roof into small roof, there are 4 ear plates on big roof, which are connected by pin and roof lifting mechanism. Total input-water sets up butterfly valve and pressure sensing instruments, output-water sets up the temperature instrumentation, the water pressure and temperature can be displayed in computer.