The utility model relates to a whole electric furnace tapping trough. Its main feature is to replace the traditional tap hole brick and tap hole slot brick with integral prefabricated parts. The overall casting of the preform, the shape from a cuboid transition to a lower height cuboid, the internal transition from a through-hole to a U-shaped groove. The device can effectively reduce the problem of too fast erosion at the joint of steel outlet brick and slot brick, and is convenient for construction, gunning and replacement, which has a strong practical value.

Compared with the common brick electric furnace top, the prefabricated parts of the electric furnace top have the advantages of convenient construction, good integrity, strong resistance to electric arc radiation (able to withstand the ultra-high temperature electric arc radiation of 2400 ℃), good wear resistance, high thermal shock stability, accurate appearance size and strong resistance to peeling.

Index Item		GG－1	GG－2	GG－3	GG－4
Al2O3, %		≥75	≥65	≥75	≥65
SiC， %		8~10	8~10	/	/
C，%		≥4	≥5	/	/
Cr2O3, %		/	/	3~5	3~5
Linear rate of changePLC（1500℃×2h）,％		±0.5	±1.0	±0.5	±0.5
Flexural strength MOR, MPa	110℃×24h	≥5	≥5	≥6	≥6
	1500℃×3h	≥10	≥10	≥10	≥10