Electric arc furnace cover mainly silica fire brick masonry in the past, but because of its high refractoriness, poor thermal shock resistance, metal and slag corrosion spalling damage occurred, short life. Later widespread use of excellent performance of high-alumina brick and high-alumina refractory unshaped refractories, 2-3 times more life than silica mortar.

As super high power electric of development, due to steelmaking rhythm accelerated, arc furnace cover work conditions more bad, have development out has various combines agent preparation of not burn high aluminum brick, or in ingredients in the introduced Silicon line stone family mineral raw materials, added micro-powder, and tip spar, and SIC,, improve brick of anti-slag performance, and high temperature volume stability and the hot earthquake stability, to meet super high power electric development of needs.

Furnace cover electrode triangle due to the more demanding working conditions, generally uses the corundum, chromium corundum and quality of corundum-spinel castables and precast, simplifies construction, improve the service life of the furnace cover. According to the electric arc furnace slag from smelting characteristics, thermal regime, and the nature of almost all basic refractories for furnace wall.